Phytochemical screening and in vitro antimicrobial activity of Thymus lanceolatus Desf. from Algeria

PubMed Central

Benbelaïd, Fethi; Khadir, Abdelmounaïm; Abdoune, Mohamed Amine; Bendahou, Mourad

2013-01-01

Objective To investigate the antimicrobial activity of an endemic Thyme, Thymus lanceolatus (T. lanceolatus), against a large number of pathogens. Methods Four solvent extracts were evaluated for antimicrobial activity using disc diffusion method and MIC determination on twenty-one strains. Results T. lanceolatus extracts showed a broad-spectrum antimicrobial activity, especially ethanol extract with inhibition zone diameters ranging from 14 to 32 mm, and MIC values from 0.052 to 0.500 mg/mL. Chloroform extract was more active against Gram-positive bacteria, since it has an inhibitory potency on Staphylococcus aureus and Enterococcus faecalis at only 31 µg/mL. While, hexane and water extracts were less effective since they were inactive against several strains. Conclusions The findings of this study indicate that T. lanceolatus has a strong antimicrobial potential, which justifies its use in folk medicine for treatment of infectious diseases. Since this species is poorly investigated, further refined studies on it pure secondary metabolites are needed and very important, in the perspective to identify new antimicrobial molecules from this endemic plant.

Lactobacillus plantarum as a Probiotic Potential from Kouzeh Cheese (Traditional Iranian Cheese) and Its Antimicrobial Activity.

PubMed

Jabbari, Vahid; Khiabani, Mahmoud Sowti; Mokarram, Reza Rezaei; Hassanzadeh, Azad Mohammad; Ahmadi, Elham; Gharenaghadeh, Sasan; Karimi, Nayyer; Kafil, Hossein Samadi

2017-06-01

The aim of this study is to isolate and identify Lactobacillus plantarum isolates from traditional cheese, Kouzeh, and evaluate their antimicrobial activity against some food pathogens. In total, 56 lactic acid bacteria were isolated by morphological and biochemical methods, 12 of which were identified as Lactobacillus plantarum by biochemical method and 11 were confirmed by molecular method. For analyzing the antimicrobial activity of these isolates properly, diffusion method was performed. The isolates were identified by 318 bp band dedicated for L. plantarum. The isolated L. plantarum represented an inhibitory activity against four of the pathogenic bacteria and showed different inhibition halos against each other. The larger halos were observed against Staphylococcus aureus and Staphylococcus epidermidis (15 ± 0.3 and 14.8 ± 0.7 mm, respectively). The inhibition halo of Escherichia coli was smaller than that of other pathogen and some L. plantarum did not show any inhibitory activity against E. coli, which were resistant to antimicrobial compounds produced by L. plantarum. The isolated L. plantarum isolates with the antimicrobial activity in this study had strong probiotic properties. These results indicated the nutritional value of Kouzeh cheese and usage of the isolated isolates as probiotic strains.

Surface-engineered core-shell nano-size ferrites and their antimicrobial activity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Baraliya, Jagdish D., E-mail: jdbaraliya@yahoo.co.in; Joshi, Hiren H., E-mail: jdbaraliya@yahoo.co.in

We report the results of biological study on core-shell structured MFe{sub 2}O{sub 4} (where M = Co, Mn, Ni) nanoparticles and influence of silica- DEG dual coating on their antimicrobial activity. Spherical MFe{sub 2}O{sub 4} nanoparticles were prepared via a Co-precipitation method. The microstructures and morphologies of these nanoparticles were studied by x-ray diffraction and FTIR. The antimicrobial activity study carried out in nutrient agar medium with addition of antimicrobial synthesis compound which is tested for its activity against different types of bacteria.

Surface-engineered core-shell nano-size ferrites and their antimicrobial activity

NASA Astrophysics Data System (ADS)

Baraliya, Jagdish D.; Joshi, Hiren H.

2014-04-01

We report the results of biological study on core-shell structured MFe2O4 (where M = Co, Mn, Ni) nanoparticles and influence of silica- DEG dual coating on their antimicrobial activity. Spherical MFe2O4 nanoparticles were prepared via a Co-precipitation method. The microstructures and morphologies of these nanoparticles were studied by x-ray diffraction and FTIR. The antimicrobial activity study carried out in nutrient agar medium with addition of antimicrobial synthesis compound which is tested for its activity against different types of bacteria.

Antimicrobial Activity of 8-Quinolinols, Salicylic Acids, Hydroxynaphthoic Acids, and Salts of Selected Quinolinols with Selected Hydroxy-Acids

PubMed Central

Gershon, Herman; Parmegiani, Raulo

1962-01-01

Seventy-seven compounds were screened by the disc-plate method against strains of five bacteria and five fungi. A new constant was proposed to describe the antimicrobial activity of a compound in a defined system of organisms. This constant includes not only the inhibitory level of activity of the material but also the number of organisms inhibited. This constant, the antimicrobial spectrum index, was compared with the antimicrobial index of Albert. PMID:13898066

Antimicrobial activity of Miconia species (Melastomataceae).

PubMed

Rodrigues, Juliana; Michelin, Danielle Carvalho; Rinaldo, Daniel; Zocolo, Guilherme Julião; dos Santos, Lourdes Campaner; Vilegas, Wagner; Salgado, Hérida Regina Nunes

2008-03-01

This work evaluated the antimicrobial activity of the methanol and chloroform extracts of the leaves of Miconia cabucu, Miconia rubiginosa, and Miconia stenostachya using the disc-diffusion method. The results obtained showed that the methanol extracts of the leaves of M. rubiginosa and M. stenostachya and the chloroform extract of the leaves of M. cabucu presented antimicrobial activity against the tested microorganisms.

Evaluation of antimicrobial activity and bronchodialator effect of a polyherbal drug-Shrishadi

PubMed Central

Kajaria, Divya Kumari; Gangwar, Mayank; Kumar, Dharmendra; Kumar Sharma, Amit; Tilak, Ragini; Nath, Gopal; Tripathi, Yamini Bhusan; Tripathi, JS; Tiwari, SK

2012-01-01

Objective To investigate antimicrobial and bronchodialator effect of hydroalcholic extract of polyherbal drug Shirishadi containing Shirisha (Albezzia lebbeck), Nagarmotha (Cyprus rotandus) & Kantakari (Solanum xanthocarpum). Methods Antimicrobial activity was evaluated by disc diffusion method and MIC, MBC, MFC were calculated by micro dilution method. Hydroalcholic extract of this preparation was investigated for its phytochemical analysis, phenol and flavonoid were determined by spectrophotometric method and in vivo bronchodilator effect was analysed by convulsion time. Results The phytochemical tests revealed presence of alkaloids, anthraquinones, carbohydrates, flavonoids, saponins and tannins. The antimicrobial result showed the MIC of 6.25 mg/mL against Staphylococcus aureus and 12.5 mg/mL for Escherichia coli and 12.5 mg/mL against remaining bacteria tested, with strong antifungal activity. The maximum inhibition zone is found against Pseudomonas aeruginosa with MIC 16 mg/mL. Drug showed significant bronchodilator effect with 27.86% & 36.13% increase in preconvulsion time of guinea pigs pretreated with 100 & 200 mg/kg body weight of extract. Conclusions The study reveals that the extracts possess antibacterial activity and antifungal activity in a dose dependent manner. This antimicrobial property may be due to presence of several saponins, further studies are highly needed for the drug development. PMID:23569869

Evaluation of antimicrobial activity and bronchodialator effect of a polyherbal drug-Shrishadi.

PubMed

Kajaria, Divya Kumari; Gangwar, Mayank; Kumar, Dharmendra; Kumar Sharma, Amit; Tilak, Ragini; Nath, Gopal; Tripathi, Yamini Bhusan; Tripathi, J S; Tiwari, S K

2012-11-01

To investigate antimicrobial and bronchodialator effect of hydroalcholic extract of polyherbal drug Shirishadi containing Shirisha (Albezzia lebbeck), Nagarmotha (Cyprus rotandus) & Kantakari (Solanum xanthocarpum). Antimicrobial activity was evaluated by disc diffusion method and MIC, MBC, MFC were calculated by micro dilution method. Hydroalcholic extract of this preparation was investigated for its phytochemical analysis, phenol and flavonoid were determined by spectrophotometric method and in vivo bronchodilator effect was analysed by convulsion time. The phytochemical tests revealed presence of alkaloids, anthraquinones, carbohydrates, flavonoids, saponins and tannins. The antimicrobial result showed the MIC of 6.25 mg/mL against Staphylococcus aureus and 12.5 mg/mL for Escherichia coli and 12.5 mg/mL against remaining bacteria tested, with strong antifungal activity. The maximum inhibition zone is found against Pseudomonas aeruginosa with MIC 16 mg/mL. Drug showed significant bronchodilator effect with 27.86% & 36.13% increase in preconvulsion time of guinea pigs pretreated with 100 & 200 mg/kg body weight of extract. The study reveals that the extracts possess antibacterial activity and antifungal activity in a dose dependent manner. This antimicrobial property may be due to presence of several saponins, further studies are highly needed for the drug development.

Antimicrobial Activity of Serbian Propolis Evaluated by Means of MIC, HPTLC, Bioautography and Chemometrics

PubMed Central

Trifković, Jelena; Berić, Tanja; Vovk, Irena; Milojković-Opsenica, Dušanka; Stanković, Slaviša

2016-01-01

New information has come to light about the biological activity of propolis and the quality of natural products which requires a rapid and reliable assessment method such as High Performance Thin-Layer Chromatography (HPTLC) fingerprinting. This study investigates chromatographic and chemometric approaches for determining the antimicrobial activity of propolis of Serbian origin against various bacterial species. A linear multivariate calibration technique, using Partial Least Squares, was used to extract the relevant information from the chromatographic fingerprints, i.e. to indicate peaks which represent phenolic compounds that are potentially responsible for the antimicrobial capacity of the samples. In addition, direct bioautography was performed to localize the antibacterial activity on chromatograms. The biological activity of the propolis samples against various bacterial species was determined by a minimum inhibitory concentration assay, confirming their affiliation with the European poplar type of propolis and revealing the existence of two types (blue and orange) according to botanical origin. The strongest antibacterial activity was exhibited by sample 26 against Staphylococcus aureus, with a MIC value of 0.5 mg/mL, and Listeria monocytogenes, with a MIC as low as 0.1 mg/mL, which was also the lowest effective concentration observed in our study. Generally, the orange type of propolis shows higher antimicrobial activity compared to the blue type. PLS modelling was performed on the HPTLC data set and the resulting models might qualitatively indicate compounds that play an important role in the activity exhibited by the propolis samples. The most relevant peaks influencing the antimicrobial activity of propolis against all bacterial strains were phenolic compounds at RF values of 0.37, 0.40, 0.45, 0.51, 0.60 and 0.70. The knowledge gained through this study could be important for attributing the antimicrobial activity of propolis to specific chemical compounds, as well as the verification of HPTLC fingerprinting as a reliable method for the identification of compounds that are potentially responsible for antimicrobial activity. This is the first report on the activity of Serbian propolis as determined by several combined methods, including the modelling of antimicrobial activity by HPTLC fingerprinting. PMID:27272728

Comparison of Antimicrobial Efficacy of Triclosan- Containing, Herbal and Homeopathy Toothpastes- An Invitro Study

PubMed Central

Fawaz, Mohammed Alimullah; Narahari, Rao; Shahela, Tanveer; Syed, Afroz

2015-01-01

Background Use of antimicrobial agents is one of the important strategies to prevent oral diseases. These agents vary in their abilities to deliver preventive and therapeutic benefits. Objectives This invitro study was conducted to assess antimicrobial efficacy of different toothpastes against various oral pathogens. Materials and Methods A total of nine toothpastes in three groups were tested for their antimicrobial activity against Escherichia coli (ATCC 25922), Staphylococcus aureus (ATCC 25923), Streptococcus mutans (ATCC 0266P) and Candida albicans (Laboratory Strain) by modified agar well diffusion method. Statistical Analysis was performed using Minitab Software. A p-value of less than 0.05 was considered significant. Results Triclosan-based dental formulation with combination of fluoride (1000ppm) exhibited higher antimicrobial activity against test organisms than the combination of lower fluoride-concentration or sodium monofluorophosphate. Among herbal dentifrices, formulation containing Neem, Pudina, Long, Babool, Turmeric and Vajradanti showed significant antimicrobial activity against all the four tested microorganisms (p<0.05). However, against Streptococcus mutans, all three herbal products showed significant antimicrobial activity. Homeo products showed least antimicrobial activity on the tested strains. Formulation with kreosotum, Plantago major and calendula was significantly effective only against Streptococcus mutans. Conclusion In the present study, antimicrobial activity of the toothpaste containing both triclosan and fluoride (1000ppm) as active ingredients showed a significant difference (p< 0.05) against all four tested microflora compared to that of with lower fluoride-concentration or sodium monofluorophosphate. Of herbal groups, the only dentifrice containing several phytochemicals was found to be significantly effective and comparable to triclosan-fluoride (1000ppm) formulation. Thus, this herbal toothpaste can be used as alternative to triclosan-based formulations. However, these results might not be clinically useful unless tested invivo. PMID:26557516

Antimicrobial Activity of Seven Essential Oils From Iranian Aromatic Plants Against Common Causes of Oral Infections

PubMed Central

Zomorodian, Kamiar; Ghadiri, Pooria; Saharkhiz, Mohammad Jamal; Moein, Mohammad Reza; Mehriar, Peiman; Bahrani, Farideh; Golzar, Tahereh; Pakshir, Keyvan; Fani, Mohammad Mehdi

2015-01-01

Background: Over the past two decades, there has been a growing trend in using oral hygienic products originating from natural resources such as essential oils (EOs) and plant extracts. Seven aromatic plants used in this study are among popular traditional Iranian medicinal plants with potential application in modern medicine as anti-oral infectious diseases. Objectives: This study was conducted to determine the chemical composition and antimicrobial activities of essential oils from seven medicinal plants against pathogens causing oral infections. Materials and Methods: The chemical compositions of EOs distilled from seven plants were analyzed by gas chromatography/mass spectrometry (GC/MS). These plants included Satureja khuzestanica, S. bachtiarica, Ocimum sanctum, Artemisia sieberi, Zataria multiflora, Carum copticum and Oliveria decumbens. The antimicrobial activity of the essential oils was evaluated by broth micro-dilution in 96 well plates as recommended by the Clinical and Laboratory Standards Institute (CLSI) methods. Results: The tested EOs inhibited the growth of examined oral pathogens at concentrations of 0.015-16 µL/mL. Among the examined oral pathogens, Enterococcus faecalis had the highest Minimum Inhibitory Concentrations (MICs) and Minimum Microbicidal Concentrations (MMCs). Of the examined EOs, S. khuzestanica, Z. multiflora and S. bachtiarica, showed the highest antimicrobial activities, respectively, while Artemisia sieberi exhibited the lowest antimicrobial activity. Conclusions: The excellent antimicrobial activities of the tested EOs might be due to their major phenolic or alcoholic monoterpenes with known antimicrobial activities. Hence, these EOs can be possibly used as an antimicrobial agent in treatment and control of oral pathogens. PMID:25793100

Analysis of phytochemical profile of Terminalia arjuna bark extract with antioxidative and antimicrobial properties.

PubMed

Mandal, Shreya; Patra, Arpita; Samanta, Animesh; Roy, Suchismita; Mandal, Arpita; Mahapatra, Tapasi Das; Pradhan, Shrabani; Das, Koushik; Nandi, Dilip Kumar

2013-12-01

To investigate phytochemical screening, antimicrobial activity and qualitative thin layer chromatographic separation of flavonoid components, antioxidant activity and total flavonoid compound of Terminalia arjuna. For phytochemical screening, some common and available standard tests were done. Antimicrobial bioassay was done through agar well diffusion method. Detection of antioxidant activity and flavonoid compounds were done through thin layer chromatography. Total antioxidant activity was measured by 2, 2-diphenyl-1-picrylhydrazyl (DPPH) in colorimetric method. Aluminum chloride colorimetric method was used for total flavonoid determination. Phytochemical screening showed the active compounds presence in high concentration, such as phytosterol, lactones, flavonoids, phenolic compounds and tannins and glycosides. The antimicrobial activity of extract showed that greater inhibition zone against Gram negative bacteria than Gram positive bacteria. This methanolic extract showed a promising antioxidant activity, as absorption of DPPH redicles decreased in DPPH free radical scavenging assay. Flavonoids components having antioxidant property present in the methanol extract at a level of 199.00 mg quercetin equivalent/g of dried methanol extract in colorimetric method. The Terminalia arjuna bark extract revealed the presence of bio-active constituents which are known to exhibit medicinal as well as physiological activities. Copyright © 2013 Asian Pacific Tropical Biomedical Magazine. Published by Elsevier B.V. All rights reserved.

Antimicrobial activity of honokiol and magnolol isolated from Magnolia officinalis.

PubMed

Ho, K Y; Tsai, C C; Chen, C P; Huang, J S; Lin, C C

2001-03-01

The antimicrobial activity of honokiol and magnolol, the main constituents of Magnolia officinalis was investigated. The antimicrobial activity was assayed by the agar dilution method using brain heart infusion medium and the minimum inhibitory concentration (MIC) were determined for each compound using a twofold serial dilution assay. The results showed that honokiol and magnolol have a marked antimicrobial effect (MIC = 25 microg/mL) against Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia, Micrococcus luteus and Bacillus subtilis, but did not show antimicrobial activity (MIC > or = 100 microg/mL) for Shigella flexneii, Staphylococcus epidermidis, Enterobacter aerogenes, Proteus vulgaris, Escherichia coli and Pseudomonas aeruginosa. Our results indicate that honokiol and magnolol, although less potent than tetracycline, show a significant antimicrobial activity for periodontal pathogens. Hence we suggest that honokiol and magnolol might have the potential to be an adjunct in the treatment of periodontitis. Copyright 2001 John Wiley & Sons, Ltd.

Screening of antimicrobial activity of macroalgae extracts from the Moroccan Atlantic coast.

PubMed

El Wahidi, M; El Amraoui, B; El Amraoui, M; Bamhaoud, T

2015-05-01

The aim of this work is the screening of the antimicrobial activity of seaweed extracts against pathogenic bacteria and yeasts. The antimicrobial activity of the dichloromethane and ethanol extracts of ten marine macroalgae collected from the Moroccan's Atlantic coast (El-Jadida) was tested against two Gram+ (Bacillus subtilis and Staphylococcus aureus) and two Gram- (Escherichia coli and Pseudomonas aeruginosa) human pathogenic bacteria, and against two pathogenic yeasts (Candida albicans and Cryptococcus neoformans) using the agar disk-diffusion method. Seven algae (70%) of ten seaweeds are active against at least one pathogenic microorganisms studied. Five (50%) are active against the two studied yeast with an inhibition diameter greater than 15 mm for Cystoseira brachycarpa. Six (60%) seaweeds are active against at least one studied bacteria with five (50%) algae exhibiting antibacterial inhibition diameter greater than 15 mm. Cystoseira brachycarpa, Cystoseira compressa, Fucus vesiculosus, and Gelidium sesquipedale have a better antimicrobial activity with a broad spectrum antimicrobial and are a potential source of antimicrobial compounds and can be subject of isolation of the natural antimicrobials. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

Isolation and determination of four potential antimicrobial components from Pseudomonas aeruginosa extracts

PubMed Central

Xu, Ling-Qing; Zeng, Jian-Wen; Jiang, Chong-He; Wang, Huan; Li, Yu-Zhen; Wen, Wei-Hong; Li, Jie-Hua; Wang, Feng; Ting, Wei-Jen; Sun, Zi-Yong; Huang, Chih-Yang

2017-01-01

Background: Pseudomonas aeruginosa can cause disease and also can be isolated from the skin of healthy people. Additionally, it exhibits certain antimicrobial effects against other microorganisms. Methods: We collected 60 strains of P. aeruginosa and screened their antimicrobial effects against Staphylococcus aureus (ATCC 25923) using the filter paper-disk method, the cross-streaking method and the co-culture method and then evaluated the antimicrobial activity of the chloroform-isolated S. aureus extracts against methicillin-resistant S. aureus (MRSA, Gram-positive cocci), vancomycin intermediate-resistant S. aureus (VISA, Gram-positive cocci), Corynebacterium spp. (CS, Gram-positive bacilli), Acinetobacter baumannii (AB, Gram-negative bacilli), Moraxella catarrhalis (MC, Gram-negative diplococcus), Candida albicans (CA, fungi), Candida tropicalis (CT, fungi), Candida glabrata (CG, fungi) and Candida parapsilosis (CP, fungi). Results: The PA06 and PA46 strains have strong antimicrobial effects. High-performance liquid chromatography (HPLC) analysis revealed that the major components of PA06 and PA46 that exhibit antimicrobial activity are functionally similar to phenazine-1-carboxylic acid (PCA) and pyocyanin. Preparative HPLC was performed to separate and isolate the 4 major potential antimicrobial components: PA06ER10, PA06ER16, PA06ER23 and PA06ER31. Further, the molecular masses of PA06ER10 (260.1), PA06ER16 (274.1), PA06ER23 (286.1) and PA06ER31 (318.2) were determined by electrospray ionization (ESI) mass spectrometry. Conclusion: P. aeruginosa can produce small molecules with potential antimicrobial activities against MRSA, VISA, CS, MC, CA, CT, CG and CP but not against AB. PMID:29200950

Formation of contact active antimicrobial surfaces by covalent grafting of quaternary ammonium compounds.

PubMed

Elena, Poverenov; Miri, Klein

2018-05-16

Different synthetic strategies for the formation of contact active antimicrobial materials utilizing covalent linkage of quaternary ammonium compounds (QACs) were reviewed. There is a demand to find methods that will prevent bacterial fouling without the release of antimicrobial agents, because biocides cause environment pollution and promote the development of bacteria resistance mechanisms. The contact active antimicrobial surfaces may provide a useful tool for this purpose. The covalent surface grafting of QACs seems to be a feasible and promising approach for the formation of safe and effective antimicrobial materials that could be utilized for medical devices, food industry, water treatment systems and other applications. This manuscript reviews covalent attachment of QACs to form contact active antimicrobial materials based on glass, metals, synthetic and natural polymers. The review emphasizes the description of different synthetic methods that are used for the covalent linkage. Direct covalent linkage of QACs to the material surfaces, a linkage via auxiliary nanoparticles (NPs), or spacers, controlled radical polymerization techniques and a linkage to pre-activated surfaces are discussed. The physico-chemical properties and biological activity of the modified surfaces are also described. This review does not cover non-covalent grafting of QACs and incorporation of QACs into a bulk material. Copyright © 2018 Elsevier B.V. All rights reserved.

Phytochemical analysis, antimicrobial, antioxidant activities and total phenols of Ferulago carduchorum in two vegetative stages (flower and fruit).

PubMed

Golfakhrabadi, Fereshteh; Shams Ardekani, Mohammad Reza; Saeidnia, Soodabeh; Yousefbeyk, Fatemeh; Jamalifar, Hossein; Ramezani, Nasrin; Akbarzadeh, Tahmineh; Khanavi, Mahnaz

2016-03-01

Ferulago carduchorum (Apiaceae family) is an endemic plant of Iran. The crude extract and four fractions of aerial parts of F. carduchorum in two vegetative stages (flower and fruit) were studied for their total phenolic contents, antimicrobial and antioxidant activities using folin-ciocalteu assay, micro dilution method and DPPH assay, respectively. The results indicated that the best antioxidant activity was determined in flower crude extract (IC50=0.44 mg/mL). The flower ethyl acetate fraction (FLE) showed better antimicrobial and antifungal activities than other fractions. So, FLE was selected for phytochemical investigations, resulting in isolation of a flavonoid (hesperetin). Hesperetin showed antimicrobial activity. The results showed that the antimicrobial and antioxidant effects during the flowering are obviously more than the fruit season.

Antimicrobial Activities of Clove and Thyme Extracts

PubMed Central

Nzeako, B C; Al-Kharousi, Zahra S N; Al-Mahrooqui, Zahra

2006-01-01

Objective: It has been postulated that geographical locations of the herbs affect the constituents of their essential oils and thus the degree of their antimicrobial action. This study examine two samples of clove obtained from Sri Lanka and Zanzibar and two samples of thyme from Iran and Oman to determine the antimicrobial potential of their extracted oils. Method: The active agents in each plant were extracted by steam distillation and by boiling. The antimicrobial activities of the extracts were determined at neat and by two-fold dilutions in well agar diffusion technique using Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, Streptococcus pyogenes, Corynebacterium species, Salmonella species, Bacteroides fragilis and Candida albicans. Results: All oil extracts possessed antimicrobial activity against all bacteria and yeast tested. Their water extracts exhibited lower antimicrobial activity, though thyme aqueous extract was active only against S. aureus. The lowest concentration of antimicrobial activity (0.1% i.e., 1:1024) was obtained with thyme oil extract using Candida albicans. There was no significant difference in antimicrobial activity between clove obtained from Sri Lanka or Zanzibar or thyme obtained from Iran or Oman. Conclusion: Our experiment showed that the country of origin of the herbs has no effect on their antimicrobial activity. However, further work is necessary to ascertain why Candida albicans displayed remarkable degree of sensitivity with the extracts than all the other organisms test. PMID:21748125

In-vitro Antimicrobial Activities of Some Iranian Conifers

PubMed Central

Afsharzadeh, Maryam; Naderinasab, Mahboobe; Tayarani Najaran, Zahra; Barzin, Mohammad; Emami, Seyed Ahmad

2013-01-01

Male and female leaves and fruits of eleven different taxons of Iranian conifers (Cupressus sempervirens var. horizontalis, C. sempervirens var. sempervirens, C. sempervirens cv. Cereifeormis, Juniperus communis subsp. hemisphaerica, J. excelsa subsp. excelsa, J. excelsa subsp. polycarpos, J. foetidissima, J. oblonga, J. sabina, Platycladus orientalis and Taxus baccata) were collected from different localities of Iran, dried and extracted with methanol. The extracts were tested for their antimicrobial activity against Pseudomonas aeruginosa, Staphylococcus aureus, Escherichia coli and Candida albicans. The extracts were screened qualitatively using four different methods, the disc diffusion, hole plate, cylinder agar diffusion and agar dilution methods, whereas the minimum inhibitory concentrations (MIC) of each extract were determined by the agar dilution method. The best result was obtained by means of hole plate method in qualitative determination of antimicrobial activities of extracts and the greatest activity was found against S. aureus in all tested methods. PMID:24250573

Antimicrobial activity of tempeh gembus hydrolyzate

NASA Astrophysics Data System (ADS)

Noviana, A.; Dieny, F. F.; Rustanti, N.; Anjani, G.; Afifah, D. N.

2018-02-01

Tropical disease can be prevented by consumming fermented foods that have antimicrobial activity. One of them is tempeh gembus that has short shelf life. It can be overcome by processing it into hydrolyzate. This study aimed to determine antimicrobial activity of tempeh gembus hydrolyzate. Tempeh gembus was made of local soybean from Grobogan. They were added 5,000 ppm, 8,000 ppm, and 10,000 ppm of bromelain enzyme (TGH BE). Antimicrobial effects of TGH BE were tested against Staphylococcus aureus, Escherichia coli, Bacillus subtilis, and Steptococcus mutans. Antimicrobial test was carried out using Kirby-Bauer Disc Diffussion method. Soluble protein test used Bradford method. The largest inhibition zone against S. aureus and S. mutans were shown by TGH BE 8,000 ppm, 0.89±0.53 mm and 2.40±0.72 mm. The largest inhibition zone of B. subtilis, 7.33±2,25 mm, was shown by TGH BE 5,000 ppm. There wasn’t antimicrobial effect of TGH BE against E. coli. There weren’t significant differences of soluble protein (P=0.293) and the inhibition zones againt S. aureus (P = 0.967), E. coli (P = 1.000), B. subtilis (P = 0.645), S. mutans (P=0.817) of all treatments. There were antimicrobial activities of TGH BE against S. aureus, B. subtilis, and S. mutans.

Anti-Inflammatory and Antimicrobial Properties of Flavonoids from Heliotropium subulatum Exudate.

PubMed

Singh, Bharat; Sharma, Ram A

2015-01-01

Heliotropium subulatum is an erect or procumbent perennial herb; leaves contain foliar trichomes and its resinous exudate is used in traditional medicine. The anti-inflammatory activity of dichloromethane fraction and isolated flavonoids was evaluated by using carrageenan and CFA-induced paw oedema models. Similarly, the disc diffusion and microdilution methods were used for the assessment of antimicrobial activity. Five isolated flavonoids were investigated for their antiinflammatory and antimicrobial activities. Eriodictyol demonstrated maximum anti-inflammatory activity (53.09%) at 30.0 mg/kg dose on 6(th) h and similarly, it inhibited the CFA-induced arthritis swelling (41.84%) with 30.0 mg/kg dose on 8(th) day respectively. As per disc diffusion and microdilution methods used for antimicrobial activity determination, the pinocembrin was found to be most active against Staphylococcus aureus (IZ=27±0.7 mm, 08 μg/ml dose) and Candida albicans (IZ=17±0.9 mm; 12 μg/ml dose). These investigated results revealed that the eriodictyol and pinocembrin showed significant anti-inflammatory and antimicrobial activities. Further studies which aimed to investigate the mechanism of action of these isolated flavonoids in the treatment of inflammations and various types of infections have been initiated.

Cytotoxic and antimicrobial activities of endophytic fungi isolated from Bacopa monnieri (L.) Pennell (Scrophulariaceae)

PubMed Central

2014-01-01

Background Endophytes, which reside in plant tissues, have the potential to produce novel metabolites with immense benefits for health industry. Cytotoxic and antimicrobial activities of endophytic fungi isolated from Bacopa monnieri (L.) Pennell were investigated. Methods Endophytic fungi were isolated from the Bacopa monnieri. Extracts from liquid cultures were tested for cytotoxicity against a number of cancer cell lines using the MTT assay. Antimicrobial activity was determined using the micro dilution method. Results 22% of the examined extracts showed potent (IC50 of <20 μg/ml) cytotoxic activity against HCT-116 cell line. 5.5%, 11%, 11% of the extracts were found to be cytotoxic for MCF-7, PC-3, and A-549 cell lines respectively. 33% extracts displayed antimicrobial activity against at least one test organism with MIC value 10–100 μg/ml. The isolate B9_Pink showed the most potent cytotoxic activity for all the cell lines examined and maximum antimicrobial activity against the four pathogens examined which was followed by B19. Conclusions Results indicated the potential for production of bioactive agents from endophytes of Bacopa monnieri. PMID:24512530

Screening antimicrobial activity of various extracts of Urtica dioica.

PubMed

Modarresi-Chahardehi, Amir; Ibrahim, Darah; Fariza-Sulaiman, Shaida; Mousavi, Leila

2012-12-01

Urtica dioica or stinging nettle is traditionally used as an herbal medicine in Western Asia. The current study represents the investigation of antimicrobial activity of U. dioica from nine crude extracts that were prepared using different organic solvents, obtained from two extraction methods: the Soxhlet extractor (Method I), which included the use of four solvents with ethyl acetate and hexane, or the sequential partitions (Method II) with a five solvent system (butanol). The antibacterial and antifungal activities of crude extracts were tested against 28 bacteria, three yeast strains and seven fungal isolates by the disc diffusion and broth dilution methods. Amoxicillin was used as positive control for bacteria strains, vancomycin for Streptococcus sp., miconazole nitrate (30 microg/mL) as positive control for fungi and yeast, and pure methanol (v/v) as negative control. The disc diffusion assay was used to determine the sensitivity of the samples, whilst the broth dilution method was used for the determination of the minimal inhibition concentration (MIC). The ethyl acetate and hexane extract from extraction method I (EA I and HE I) exhibited highest inhibition against some pathogenic bacteria such as Bacillus cereus, MRSA and Vibrio parahaemolyticus. A selection of extracts that showed some activity was further tested for the MIC and minimal bactericidal concentrations (MBC). MIC values of Bacillus subtilis and Methicillin-resistant Staphylococcus aureus (MRSA) using butanol extract of extraction method II (BE II) were 8.33 and 16.33mg/mL, respectively; while the MIC value using ethyl acetate extract of extraction method II (EAE II) for Vibrio parahaemolyticus was 0.13mg/mL. Our study showed that 47.06% of extracts inhibited Gram-negative (8 out of 17), and 63.63% of extracts also inhibited Gram-positive bacteria (7 out of 11); besides, statistically the frequency of antimicrobial activity was 13.45% (35 out of 342) which in this among 21.71% belongs to antimicrobial activity extracts from extraction method I (33 out of 152 of crude extracts) and 6.82% from extraction method II (13 out of 190 of crude extracts). However, crude extracts from method I exhibited better antimicrobial activity against the Gram-positive bacteria than the Gram-negative bacteria. The positive results on medicinal plants screening for antibacterial activity constitutes primary information for further phytochemical and pharmacological studies. Therefore, the extracts could be suitable as antimicrobial agents in pharmaceutical and food industry.

Total antioxidant activity and antimicrobial potency of the essential oil and oleoresin of Zingiber officinale Roscoe

PubMed Central

Bellik, Yuva

2014-01-01

Objective To compare in vitro antioxidant and antimicrobial activities of the essential oil and oleoresin of Zingiber officinale Roscoe. Methods The antioxidant activity was evaluated based on the ability of the ginger extracts to scavenge ABTS°+ free radical. The antimicrobial activity was studied by the disc diffusion method and minimal inhibitory concentration was determined by using the agar incorporation method. Results Ginger extracts exerted significant antioxidant activity and dose-depend effect. In general, oleoresin showed higher antioxidant activity [IC50=(1.820±0.034) mg/mL] when compared to the essential oil [IC50=(110.14±8.44) mg/mL]. In terms of antimicrobial activity, ginger compounds were more effective against Escherichia coli, Bacillus subtilis and Staphylococcus aureus, and less effective against Bacillus cereus. Aspergillus niger was least, whereas, Penicillium spp. was higher sensitive to the ginger extracts; minimal inhibitory concentrations of the oleoresin and essential oil were 2 mg/mL and 869.2 mg/mL, respectively. Moreover, the studied extracts showed an important antifungal activity against Candida albicans. Conclusions The study confirms the wide application of ginger oleoresin and essential oil in the treatment of many bacterial and fungal diseases.

Methods of Antimicrobial Coating of Diverse Materials

NASA Technical Reports Server (NTRS)

Akse, James R.; Holtsnider, John T.; Kliestik, Helen

2011-01-01

Methods of coating diverse substrate materials with antimicrobial agents have been developed. Originally intended to reduce health risks to astronauts posed by pathogenic microorganisms that can grow on surfaces in spacecraft, these methods could also be used on Earth for example, to ensure sterility of surgical inserts and other medical equipment. The methods involve, generally, chemical preparation of substrate surfaces to enable attachment of antimicrobial molecules to the substrate surfaces via covalent bonds. Substrate materials that have been treated successfully include aluminum, glass, a corrosion-resistant nickel alloy, stainless steel, titanium, and poly(tetrafluoroethylene). Antimicrobial agents that have been successfully immobilized include antibiotics, enzymes, bacteriocins, bactericides, and fungicides. A variety of linkage chem istries were employed. Activity of antimicrobial coatings against gram-positive bacteria, gram-negative bacteria, and fungi was demonstrated. Results of investigations indicate that the most suitable combination of antimicrobial agent, substrate, and coating method depends upon the intended application.

Microwave Assisted Synthesis of 1-[5-(Substituted Aryl)-1H-Pyrazol-3-yl]-3,5-Diphenyl-1H-1,2,4-Triazole as Antinociceptive and Antimicrobial Agents

PubMed Central

Khanage, Shantaram Gajanan; Mohite, Popat Baban; Pandhare, Ramdas Bhanudas; Raju, S. Appala

2014-01-01

Purpose: An efficient technique has been developed for microwave assisted synthesis of 1-[5-(substituted aryl)-1H-pyrazol-3-yl]-3,5-diphenyl-1H-1,2,4-triazole as antinociceptive and antimicrobial agents. Methods: The desired compounds (S1-S10) were synthesized by the microwave irradiation via cyclization of formerly synthesized chalcones of 3,5-diphenyl-1H-1,2,4-triazole and hydrazine hydrate in mild acidic condition. All newly synthesized compounds were subjected to study their antinociceptive and antimicrobial activity. The analgesic potential of compounds was tested by acetic acid induced writhing response and hot plate method. The MIC values for antimicrobial activity were premeditated by liquid broth method. Results: The compounds S1, S2, S4, S6 and S10 were found to be excellent peripherally acting analgesic agents when tested on mice by acetic acid induced writhing method and compounds S3, S6 and S1 at dose level of 100 mg/kg were exhibited superior centrally acting antinociceptive activity when tested by Eddy’s hot plate method. In antimicrobial activity compound S10 found to be broad spectrum antibacterial agent at MIC value of 15.62 µg/ml and compound S6 was exhibited antifungal potential at 15.62 µg/mL on both fungal strains. Conclusion: Some novel pyrazoles clubbed with 1,2,4-triazole derivatives were synthesized and evaluated as possible antimicrobial, centrally and peripherally acting analgesics. PMID:24511473

Caryocar brasiliense supercritical CO2 extract possesses antimicrobial and antioxidant properties useful for personal care products

PubMed Central

2014-01-01

Background The cosmetic and pharmaceutical industries have an increasing interest in replacing synthetic antimicrobials in dermatological products due to increased microbial resistance to conventional antimicrobial agents. Pequi (Caryocar brasiliense) is a native fruit tree of the Brazilian Cerrado, specifically used in cosmetics, in the food industry, and for medicinal purposes. Leishmanicidal and antifungal activities have been reported previously. This study was designed to evaluate the antimicrobial and antioxidant activities of a C. brasiliense extract obtained by supercritical CO2 extraction. Methods The minimum inhibitory concentrations (MICs) against Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus were determined by the classical microdilution method. Antiseptic activity against these organisms was evaluated by the plate diffusion method. The antioxidant potential of the extract was evaluated using a method based on the oxidation of 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS). The extract’s chemical profile was analyzed for the presence of alkaloids, saponins, anthraquinones, steroids, tannins, flavonoids, and phenolic compounds according to standard colorimetric methods. Results The C. brasiliense supercritical CO2 extract exhibits antimicrobial activity against all bacteria tested. It also possesses antioxidant activity, when compared to a vitamin E standard. Conclusions The C. brasiliense supercritical CO2 extract may be useful for the development of personal care products, primarily for antiseptic skin products that inactivate, reduce, prevent, or arrest the growth of microorganisms with the inherent intent to mitigate or prevent disease as well as products that minimize damage caused by free radicals. PMID:24565304

Silver nanoparticles: Antimicrobial activity, cytotoxicity, and synergism with N-acetyl cysteine.

PubMed

Hamed, Selwan; Emara, Mohamed; Shawky, Riham M; El-Domany, Ramadan A; Youssef, Tareq

2017-08-01

The fast progression of nanotechnology has led to novel therapeutic interventions. Antimicrobial activities of silver nanoparticles (Ag NPs) were tested against standard ATCC strains of Staphylococcus aureus (ATCC 9144), Escherichia coli (O157:H7), Pseudomonas aeruginosa (ATCC 27853), and Candida albicans (ATCC 90028) in addition to 60 clinical isolates collected from cancer patients. Antimicrobial activity was tested by disk diffusion method and MIC values for Ag NPs alone and in combination with N-acetylcysteine (NAC) against tested pathogens were determined by broth microdilution method. Ag NPs showed a robust antimicrobial activity against all tested pathogens and NAC substantially enhanced the antimicrobial activity of Ag NPs against all tested pathogens. Synergism between Ag NPs and NAC has been confirmed by checkerboard assay. The effect of Ag NPs on tested pathogens was further scrutinized by Transmission Electron Microscope (TEM) which showed disruption of cell wall in both bacteria and fungi. Ag NPs abrogated the activity of respiratory chain dehydrogenase of all tested pathogens and released muramic acid content from S. aureus in culture. The cytotoxic effect of Ag NPs alone and in combination with NAC was examined using human HepG2 cells and this revealed no cytotoxicity at MIC values of Ag NPs and interestingly, NAC reduced the cytotoxic effect of Ag NPs at concentrations higher than their MIC values. Taken together, Ag NPs have robust antimicrobial activity and NAC substantially enhances their antimicrobial activities against MDR pathogens which would provide a novel safe, effective, and inexpensive therapeutic approach to control the prevalence of MDR pathogens. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Isolation and Antimicrobial Activity of Flavonoid Compounds from Mahagony Seeds (Swietenia macrophylla, King)

NASA Astrophysics Data System (ADS)

Mursiti, S.; Supartono

2017-02-01

Flavonoid is one of the secondary metabolites compounds in mahogany seeds. Mahogany seeds can be used as an antimicrobial. This study aims to determine the antimicrobial activity of flavonoid compounds from mahogany seeds against Escherichia coli (E.coli) and Bacillus cereus (B.cereus). Isolation of flavonoid compounds done step by step. First, the maceration using n-hexane, then with methanol. The methanol extract was dissolved in ethyl acetate and aquadest, then separated. Ethyl acetate extract evaporated Flavonoid compounds were. The testing of antimicrobial activity of flavonoid compounds using the absorption method. The results showed that the antimicrobial activity of flavonoid compounds from mahogany seeds shows the inhibitory activity and provide clear zone against bacteria E.coli with value Inhibitory Regional Diameter 18.50 mm respectively, and 14.50 mm to the bacteria. Based on the results of the study, it can be concluded that flavonoid compounds from mahogany seeds have antimicrobial activity against E.coli and B.cereus.

Effects of nisin on the antimicrobial activity of d-limonene and its nanoemulsion.

PubMed

Zhang, Zijie; Vriesekoop, Frank; Yuan, Qipeng; Liang, Hao

2014-05-01

d-Limonene has been considered to be a safer alternative compared to synthetic antimicrobial food additives. However, its hydrophobic and oxidative nature has limited its application in foods. The purpose of this research was to study effects of nisin on the antimicrobial activity of d-limonene and its nanoemulsion and develop a novel antimicrobial delivery system by combining the positive effect of these two antibacterial agents at the same time. By the checkerboard method, both the synergistic and additive effects of d-limonene and nisin were found against four selected food-related microorganisms. Then, d-limonene nanoemulsion with or without nisin was prepared by catastrophic phase inversion method, which has shown good droplet size and stability. The positive effects and outstanding antimicrobial activity of d-limonene nanoemulsion with nisin were confirmed by MICs comparison, scanning electron microscopy and determination of cell constituents released. Overall, the research described in the current article would be helpful in developing a more effective antimicrobial system for the production and preservation of foods. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.

Antimicrobial activity-guided identification of compounds from the deciduous leaves of Malus doumeri by HPLC-ESI-QTOF-MS/MS.

PubMed

Shen, Bingbing; Zhou, Rongrong; Yang, Yupei; Li, Jiayu; Liang, Xuejuan; Chen, Lin; Huang, Luqi; Zhang, Shuihan

2018-04-03

This paper intends to identify the antimicrobial activity compounds from the deciduous leaves of Malus doumeri (Dong Li Tea) by HPLC-ESI-QTOF-MS/MS. The ethanol extracts of Malus doumeri were partitioned into petroleum ether, dichloromethane, ethyl acetate, n-butanol and water fraction, respectively. The antimicrobial screening experiments showed that ethyl acetate fraction has a certain antibacterial activity by inhibition zone method in vitro. And then we used the HPLC-ESI-QTOF-MS/MS method to verify the identities of bioactive compounds. Finally, 41 compounds were determined and 11 of which were firstly reported in this plant. Notably, compounds (32, 34, 38) are new dihydrochalcones, and three chlorogenic acid analogues (10, 13, 17) may be potential antimicrobial active ingredient. Which is of great significance to the isolation of novel compounds and the discovery of new natural preservative candidates from the deciduous leaves of Malus doumeri.

Antimicrobial activity of chemically modified dextran derivatives.

PubMed

Tuchilus, Cristina G; Nichifor, Marieta; Mocanu, Georgeta; Stanciu, Magdalena C

2017-04-01

Cationic amphiphilic dextran derivatives with a long alkyl group attached to the reductive end of the polysaccharide chain and quaternary ammonium groups attached as pendent groups to the main dextran backbone were synthesized and tested for their antimicrobial properties against several bacteria and fungi strains. Dependence of antimicrobial activity on both polymer chemical composition (dextran molar mass, length of end alkyl group and chemical structure of ammonium groups) and type of microbes was highlighted by disc-diffusion method (diameter of inhibition zone) and broth microdilution method (minimum inhibitory concentrations). Polymers had antimicrobial activity for all strains studied, except for Pseudomonas aeruginosa ATCC 27853. The best activity against Staphylococcus aureus (Minimun Inhibitory Concentration 60μg/mL) was provided by polymers obtained from dextran with lower molecular mass (Mn=4500), C 12 H 25 or C 18 H 37 end groups, and N,N-dimethyl-N-benzylammonium pendent groups. Copyright © 2017 Elsevier Ltd. All rights reserved.

[In vitro studies on antioxidant and antimicrobial activities of polysaccharide from Lycoris aurea].

PubMed

Ru, Qiao-Mei; Pei, Zhen-Ming; Zheng, Hai-Lei

2008-10-01

To study the preliminary antioxidant and antimicrobial activities of polysaccharide extracted from Lycoris aurea. The scavenging activities of the polysaccharide in vitro on superoxide radical (O2-*), hydroxyl radical (*OH), alkyl radical (R*) and hydrogen peroxide (H2O2) were investigated by modified chemical systems. Meanwhile, the antimicrobial activities were tested using paper-discagar diffusion method. In general, the antioxidant activities of the polysaccharide were lower compared with Vc. However, the scavenging effects to *OH and H2O2 were parallel to Vc. Meanwhile, polysaccharide from Lycoris aurea had strong antimicrobial activities against Micrococcus luteus, Bacillus pumilus and Staphylococcus aureus. The polysaccharide extracted from L. aurea can scavenge *OH and H2O2 effectively and inhibit Gram-positive bacterias.

Triterpenoids from Acacia ataxacantha DC: antimicrobial and antioxidant activities.

PubMed

Amoussa, Abdou Madjid O; Lagnika, Latifou; Bourjot, Mélanie; Vonthron-Senecheau, Cathérine; Sanni, Ambaliou

2016-08-12

Acacia ataxacantha is a medicinal specie used extensively in traditional medicine of Benin republic to treat infectious diseases. Our previous study showed interesting antibacterial and antifungal activities against six strains of bacteria and six strains of fungi. The aim of this study was to investigate the antimicrobial and antioxidant activities of compounds isolated from A. ataxacantha. Chromatographic and spectroscopic methods were used to isolate and identify three compounds (1-3) from the bark of A. ataxacantha. Phytochemical investigation of A. ataxacantha (Fabaceae) led to the isolation of three triterpenoids (1-3). The structure of isolated compounds was established by differents spectroscopic methods such as UV, (1)H NMR, (13)C NMR, 2D NMR and Mass. All isolated compounds were tested for antimicrobial activity using agar disc-diffusion and microdilution methods. The radical scavenging activity of isolated compounds was assessed using 2,2-diphenyl-1-picrylhydrazyl (DPPH) method. Phytochemical investigation led to the isolation and identification of lupeol (1), betulinic acid (2) and betulinic acid-3-trans-caffeate (3). Moderate antimicrobial activity was obtained with compound 3 against methicillin-resitant Staphylococcus aureus, Enterococcus feacalis and Pseudomonas aeruginosa with MIC value of 25 μg/ml and Staphylococcus aureus (MIC of 50 μg/ml). Compounds 3 was more active against Staphylococcus epidermidis and Candida albicans with a MIC value of 12.5 μg/ml in boths cases. Compounds 3 had also interesting antioxidant activity with an IC50 of 3.57 μg/ml compared to quercetin (1.04 μg/ml). The overall results of this study provide evidence that the compound 3, isolated from A. ataxacantha, exhibit antimicrobial activity against Gram-positive and Gram-negative bacteria and yeast, especially against C. albicans.

Antimicrobial properties of conventional restorative filling materials and advances in antimicrobial properties of composite resins and glass ionomer cements-A literature review.

PubMed

Farrugia, Cher; Camilleri, Josette

2015-04-01

It has been reported that complete caries removal from cavities during restoration of teeth is difficult. Furthermore with the tissue saving approach it is expected that more of the saved affected tissue will possibly harbor more residual bacteria. Antimicrobial restorative filling materials would be ideal to prevent the spread of caries after completion of tooth restoration, thus preventing recurrent decay and eventually restoration failure. This paper reviews the literature on the antimicrobial properties of dental restorative filling materials. Pubmed searches on the antibacterial properties of restorative materials were carried out. Keywords were chosen to assess antibacterial properties of conventional filling materials. Methods of introducing antimicrobial agents in restorative materials were also reviewed together with the methodology used to assess antimicrobial activity. 174 articles from 1983 till 2014 were included. Adhesive materials have decreased antimicrobial activity when compared to amalgams and zinc oxides. Several techniques have been employed in order to increase the antimicrobial activity of restorative materials. Although antimicrobial activity of restorative materials is important, the introduction of antimicrobial agents/techniques should not be at the expense of other material properties. Environmental changes within a material may affect the bacterial response to the antimicrobial. Bacterial adhesion to the restorative materials should be assessed. Long term assessment of antimicrobial activity is important and is clinically relevant. The use of antimicrobial dental materials is important unless such characteristics are gained to the detriment of other material properties. Copyright © 2014 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

Antimicrobial Polymeric Materials with Quaternary Ammonium and Phosphonium Salts

PubMed Central

Xue, Yan; Xiao, Huining; Zhang, Yi

2015-01-01

Polymeric materials containing quaternary ammonium and/or phosphonium salts have been extensively studied and applied to a variety of antimicrobial-relevant areas. With various architectures, polymeric quaternary ammonium/phosphonium salts were prepared using different approaches, exhibiting different antimicrobial activities and potential applications. This review focuses on the state of the art of antimicrobial polymers with quaternary ammonium/phosphonium salts. In particular, it discusses the structure and synthesis method, mechanisms of antimicrobial action, and the comparison of antimicrobial performance between these two kinds of polymers. PMID:25667977

Antioxidant and antimicrobial activities of solvent fractions of Vernonia cinerea (L.) Less leaf extract.

PubMed

Sonibare, Mubo A; Aremu, Oluwafunmilola T; Okorie, Patricia N

2016-06-01

Vernonia cinerea (L.) Less is used in folk medicine as a remedy for various diseases. The present study reports antioxidant and antimicrobial activities of solvent fractions of Vernonia cinerea. The antioxidant properties of solvent fractions of V. cinerea were evaluated by determining radicals scavenging activity, total flavonoid and phenolic contents measured with the 2,2-diphenyl-1-picryl hydrazyl (DPPH) test, the aluminum chloride and the Folin-ciocalteau methods, respectively. Antimicrobial activities were tested against human pathogenic microorganisms using agar diffusion method. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of each active extract were determined. The ethyl acetate fraction having the IC50 value of 6.50 µg/mL demonstrated comparable DPPH radical-scavenging activity with standard antioxidants, gallic acid and quercetin included in the study. All fractions displayed moderate antimicrobial potential against the tested pathogens with the zone of inhibition that ranged from 9.0 to 13.5 mm. The MIC (1.56 mg/mL) and MBC (3.13 mg/mL) indicated highest susceptibility of Candida albicans in all fractions. The results of this study showed that the solvent fractions of V. cinerea possess antioxidant and antimicrobial activities, hence justifying the folkloric use of the plant for the treatment of various ailments in traditional medicine.

Antimicrobial activity of jasmine oil against oral microorganisms

NASA Astrophysics Data System (ADS)

Thaweboon, S.; Thaweboon, B.; Kaypetch, R.

2018-02-01

Jasmine sambac is a species of jasmine indigenous to the tropical and warm temperature regions in particular West and Southeast Asia. Essential oil extracted from the flowers of J. sambac has been shown to have anti-oxidant activity. However, very little information regarding antimicrobial activity especially oral microorganisms exists. Objective: To investigate antimicrobial effect of essential oil extracted from flowers of J. sambac against various oral microorganisms. Materials and Methods: Oral microbial strains used in the study were Streptococcus mutans KPSK2, Staphylococcus aureus ATCC 5638, Lactobacillus casei ATCC 6363, Klebsiella pneumoniae (clinical isolate), Escherichia coli ATCC 25922, Candida albicans ATCC 10231, Candida krusei ATCC 6258, Candida parapsilosis ATCC 22019, Candida tropicalis (clinical isolate), Candida glabrata ATCC 90030, Candida pseudotropicalis (clinical isolate) and Candida stellatoidia (clinical isolate). The potential of microbial growth inhibition of the oil was firstly screened by Kirby-Bauer disk diffusion method and then the minimum inhibitory concentration (MIC) was determined by agar dilution method. Results: Jasmine oil showed antimicrobial activities against S. mutans, L. casei, E. coli and all strains of Candida species with the zones of inhibition ranging from 9 to 26 mm and MIC values of 0.19-1.56 %v/v. Conclusion: Results from the present study are scientific evidence to demonstrate that jasmine oil could be employed as a natural antimicrobial agent against oral microorganisms.

Antimicrobial effects of Thai medicinal plants against acne-inducing bacteria.

PubMed

Chomnawang, Mullika Traidej; Surassmo, Suvimol; Nukoolkarn, Veena S; Gritsanapan, Wandee

2005-10-03

Propionibacterium acnes and Staphylococcus epidermidis have been recognized as pus-forming bacteria triggering an inflammation in acne. The present study was conducted to evaluate antimicrobial activities of Thai medicinal plants against these etiologic agents of acne vulgaris. Crude extracts were tested for antimicrobial activities by disc diffusion and broth dilution methods. The results from the disc diffusion method showed that 13 medicinal plants could inhibit the growth of Propionibacterium acnes. Among those, Senna alata, Eupatorium odoratum, Garcinia mangostana, and Barleria lupulina had strong inhibitory effects. Based on a broth dilution method, the Garcinia mangostana extract had the greatest antimicrobial effect. The MIC values were the same (0.039 mg/ml) for both bacterial species and the MBC values were 0.039 and 0.156 mg/ml against Propionibacterium acnes and Staphylococcus epidermidis, respectively. In bioautography assay, the Garcinia mangostana extract produced strong inhibition zones against Propionibacterium acnes. Antimicrobial activity from fractions of column chromatography revealed one of the active compounds in Garcinia mangostana could be mangostin, a xanthone derivative. Taken together, our data indicated that Garcinia mangostana had a strong inhibitory effect on Propionibacterium acnes and Staphylococcus epidermidis. Therefore, this plant would be an interesting topic for further study and possibly for an alternative treatment for acne.

Application of Artificial Intelligence to the Prediction of the Antimicrobial Activity of Essential Oils.

PubMed

Daynac, Mathieu; Cortes-Cabrera, Alvaro; Prieto, Jose M

2015-01-01

Essential oils (EOs) are vastly used as natural antibiotics in Complementary and Alternative Medicine (CAM). Their intrinsic chemical variability and synergisms/antagonisms between its components make difficult to ensure consistent effects through different batches. Our aim is to evaluate the use of artificial neural networks (ANNs) for the prediction of their antimicrobial activity. Methods. The chemical composition and antimicrobial activity of 49 EOs, extracts, and/or fractions was extracted from NCCLS compliant works. The fast artificial neural networks (FANN) software was used and the output data reflected the antimicrobial activity of these EOs against four common pathogens: Staphylococcus aureus, Escherichia coli, Candida albicans, and Clostridium perfringens as measured by standardised disk diffusion assays. Results. ANNs were able to predict >70% of the antimicrobial activities within a 10 mm maximum error range. Similarly, ANNs were able to predict 2 or 3 different bioactivities at the same time. The accuracy of the prediction was only limited by the inherent errors of the popular antimicrobial disk susceptibility test and the nature of the pathogens. Conclusions. ANNs can be reliable, fast, and cheap tools for the prediction of the antimicrobial activity of EOs thus improving their use in CAM.

Application of Artificial Intelligence to the Prediction of the Antimicrobial Activity of Essential Oils

PubMed Central

Daynac, Mathieu; Cortes-Cabrera, Alvaro; Prieto, Jose M.

2015-01-01

Essential oils (EOs) are vastly used as natural antibiotics in Complementary and Alternative Medicine (CAM). Their intrinsic chemical variability and synergisms/antagonisms between its components make difficult to ensure consistent effects through different batches. Our aim is to evaluate the use of artificial neural networks (ANNs) for the prediction of their antimicrobial activity. Methods. The chemical composition and antimicrobial activity of 49 EOs, extracts, and/or fractions was extracted from NCCLS compliant works. The fast artificial neural networks (FANN) software was used and the output data reflected the antimicrobial activity of these EOs against four common pathogens: Staphylococcus aureus, Escherichia coli, Candida albicans, and Clostridium perfringens as measured by standardised disk diffusion assays. Results. ANNs were able to predict >70% of the antimicrobial activities within a 10 mm maximum error range. Similarly, ANNs were able to predict 2 or 3 different bioactivities at the same time. The accuracy of the prediction was only limited by the inherent errors of the popular antimicrobial disk susceptibility test and the nature of the pathogens. Conclusions. ANNs can be reliable, fast, and cheap tools for the prediction of the antimicrobial activity of EOs thus improving their use in CAM. PMID:26457111

Antimicrobial synergism and cytotoxic properties of Citrus limon L., Piper nigrum L. and Melaleuca alternifolia (Maiden and Betche) Cheel essential oils.

PubMed

Nikolić, Miloš M; Jovanović, Katarina K; Marković, Tatjana Lj; Marković, Dejan Lj; Gligorijević, Nevenka N; Radulović, Siniša S; Kostić, Marina; Glamočlija, Jasmina M; Soković, Marina D

2017-11-01

The chemical composition, antimicrobial and synergistic effect, and cytotoxic activity of Citrus limon (lemon), Piper nigrum (green pepper) and Melaleuca alternifoila (tea tree) essential oils (EOs) were investigated. Chemical analyses of essential oils were tested by GC-FID and GC-MS spectroscopy. The antimicrobial activity assay was conducted using microdilution method against several oral bacteria and Candida spp. originating from the humans with oral disorders. The synergistic antimicrobial activity was evaluated using checkerboard method. The cytotoxicity evaluation of EOs was assessed using MTT test. Limonene (37.5%) and β-pinene (17.9%) were the major compounds in C. limon oil, β-pinene (34.4%), δ-3-carene (19.7%), limonene (18.7%) and α-pinene (10.4%) in P. nigrum oil and terpinen-4-ol (38.6%) and γ-terpinene (21.7%) in M. alternifolia oil. The broad-spectrum antimicrobial activity was achieved by tested three EOs, with C. limon oil being the strongest against bacteria and M. alternifolia oil strongest against fungi. The EOs demonstrated synergism; their combined application revealed an increase in antimicrobial activity. All tested essential oils showed lower cytotoxic activity in comparison with the positive control, and the obtained results confirmed a dose-dependent activity. The results of this study encourage use of tested EOs in development of a novel agent intended for prevention or therapy of corresponding oral disorders. © 2017 Royal Pharmaceutical Society.

Physics and chemistry of antimicrobial behavior of ion-exchanged silver in glass.

PubMed

Borrelli, N F; Senaratne, W; Wei, Y; Petzold, O

2015-02-04

The results of a comprehensive study involving the antimicrobial activity in a silver ion-exchanged glass are presented. The study includes the glass composition, the method of incorporating silver into the glass, the effective concentration of the silver available at the glass surface, and the effect of the ambient environment. A quantitative kinetic model that includes the above factors in predicting the antimicrobial activity is proposed. Finally, experimental data demonstrating antibacterial activity against Staphylococcus aureus with correlation to the predicted model is shown.

Antimicrobial properties of nano-silver: a cautionary approach to ionic interference.

PubMed

Sheehy, K; Casey, A; Murphy, A; Chambers, G

2015-04-01

Metallic nanoparticles such as nano-silver have found many applications as alternative antimicrobials in recent years. However methods for determining their proposed antimicrobial activity have received little attention to date. The disk diffusion assay is commonly used as a demonstration of antimicrobial properties and is a regular feature in synthetic nanoparticle papers. The aim of this study was to assess its effectiveness in demonstrating the "nanoparticle specific" antimicrobial properties in the absence of ionic contributions from unreacted reducing agents and or impurities. The disk diffusion assay was carried out on a range of silver nanoparticles, both in-house synthesised and commercially available, using Escherichia coli ATCC 25922 as a model organism. Capped and purified nanoparticles show no antimicrobial activity despite claims to the contrary for this assay. Results will be discussed in terms of the need for researchers without a background in microbiology to understand the mechanism of antimicrobial action before choosing an assay. Also discussed is the importance understanding the physiochemical characteristics of when interpreting results. Finally the relevance of the results in terms establishing protocols for method development for 'nanoparticle specific' antimicrobial properties will also be considered. Copyright © 2014 Elsevier Inc. All rights reserved.

[Study on the Chinese herbal formula for treatment of vaginitis and the antimicrobial activity in murine models].

PubMed

Fu, Ting-ting; Wu, Jian-yuan; Wang, Li; Ma, Yao; Wang, Ying; Liu, Ying; Ding, Hong

2006-09-01

To study on the various proportions of Radix Sophorae Flavescentis, Cortex Phellodendri, Fructus Cnidii and pericarp of Zanthoxylum bungeanum Maxim in the formulas, whose antimicrobial effects on E. coli, S. aureus, P. aeruginosa and C. albicans under different pH values were compared in vitro. According to Chinese ancient proved recipe, the K-B method and plate diluting method were adopted to measure antimicrobial activity, and orthogonal design to ascertain the herbal formula in vitro. Finally, murine models were established to test the antimicrobial activity in vivo through vaginal membrane irritancy experiment, negative rate of pathogeny and pathological grade of vaginal membrane. The results suggested that formulas with different proportions of the herbs had diverse antimicrobial activities, and the effect was shown to be most obvious when one milliliter drug contains 100 microl Fructus Cnidii-pericarp of Zanthoxylum bungeanum (2:1) co-extracted volatile oil and 50 microl Radix Sophorae Flavescentis and Cortex Phenodendri ethanol extraction respectively under pH6. The antimicrobial effect of the formula, which hardly had any membrane irritancy, was better than Jie Eryin in vitro and vivo. The fromula has few components and better effect, and adaptation to the pH value of vaginitis. It is a promising alternative for gynecological diseases.

Chemical Composition and Antimicrobial Activities of Iranian Propolis

PubMed Central

Afrouzan, Houshang; Tahghighi, Azar; Zakeri, Sedigheh; Es-haghi, Ali

2018-01-01

Background: With considering the importance of natural products for their remedial and therapeutic value, this research was aimed to analyze the chemical compositions and antimicrobial activity of four propolis samples from different areas of Iran (Chenaran, Taleghan, Morad Beyg, and Kalaleh) with various climates and flora. Methods: Ethanolic (70% EtOH) and dichlromethane (DCM) extracts of Iranian propolis were analyzed by gas chromatography-mass spectrometry (GC-MS) methods, and antimicrobial activity was evaluated against Candida albicans, Escherichia coli, and Staphylococcus aureus using disk diffusion antimicrobial method. Results: The results of GC-MS analysis showed the presence of fatty acids, flavonoids, terpenes, aromatic-aliphatic acids, and their related esters. The total flavonoids in DCM extract of Chenaran, Taleghan, Morad Beyg, and Kalaleh propolis were pinocembrin and pinostrobin chalcone. The common phenolic and terpene compounds detected in all four tested EtOH extracts were P-cumaric acid and dimethyl -1,3,5,6-tetramethyl-[1,3-(13C2)] bicycloce [5.5.0] dodeca-1,3,5,6,8,10-hexaene-9,10-dicarboxylate, respectively. The highest inhibitory diameter zone of the Iranian propolis against C. albicans, E. coli, and S. aureus was for DCM extract of Kalaleh propolis (13.33 mm), Morad Beyg propolis (12 mm), and Kalaleh (11.67 mm), respectively. Conclusion: Iranian propolis showed antimicrobial activities against C. albicans, E. coli, and S. aurous, perhaps due to the presence of flavonoids, phenolic acids, and terpenes as active components that can be used alone or in combination with the selected antibiotics to synergize antibiotic effect, as well as to prevent microbial resistance to available antimicrobial drugs. PMID:28558440

Native Brazilian plants against nosocomial infections: a critical review on their potential and the antimicrobial methodology.

PubMed

H Moreno, Paulo Roberto; da Costa-Issa, Fabiana Inácio; Rajca-Ferreira, Agnieszka K; Pereira, Marcos A A; Kaneko, Telma M

2013-01-01

The growing incidences of drug-resistant pathogens have increased the attention on several medicinal plants and their metabolites for antimicrobial properties. These pathogens are the main cause of nosocomial infections which led to an increasing mortality among hospitalized patients. Taking into consideration those factors, this paper reviews the state-of-the-art of the research on antibacterial agents from native Brazilian plant species related to nosocomial infections as well as the current methods used in the investigations of the antimicrobial activity and points out the differences in techniques employed by the authors. The antimicrobial assays most frequently used were broth microdilution, agar diffusion, agar dilution and bioautography. The broth microdilution method should be the method of choice for testing new antimicrobial agents from plant extracts or isolated compounds due to its advantages. At the moment, only a small part of the rich Brazilian flora has been investigated for antimicrobial activity, mostly with unfractionated extracts presenting a weak or moderate antibacterial activity. The combination of crude extract with conventional antibiotics represents a largely unexploited new form of chemotherapy with novel and multiple mechanisms of action that can overcome microbial resistance that needs to be further investigated. The antibacterial activity of essential oil vapours might also be an interesting alternative treatment of hospital environment due to their ability in preventing biofilm formation. However, in both alternatives more studies should be done on their mode of action and toxicological effects in order to optimize their use.

The Activity of Antimicrobial Surfaces Varies by Testing Protocol Utilized

PubMed Central

Campos, Matias D.; Zucchi, Paola C.; Phung, Ann; Leonard, Steven N.; Hirsch, Elizabeth B.

2016-01-01

Background Contaminated hospital surfaces are an important source of nosocomial infections. A major obstacle in marketing antimicrobial surfaces is a lack of efficacy data based on standardized testing protocols. Aim We compared the efficacy of multiple testing protocols against several “antimicrobial” film surfaces. Methods Four clinical isolates were used: one Escherichia coli, one Klebsiella pneumoniae, and two Staphylococcus aureus strains. Two industry methods (modified ISO 22196 and ASTM E2149), a “dried droplet”, and a “transfer” method were tested against two commercially available antimicrobial films, one film in development, an untreated control, and a positive (silver) control film. At 2 (only ISO) and 24 hours following inoculation, bacteria were collected from film surfaces and enumerated. Results Compared to untreated films in all protocols, there were no significant differences in recovery on either commercial brand at 2 or 24 hours after inoculation. The silver surface demonstrated significant microbicidal activity (mean loss 4.9 Log10 CFU/ml) in all methods and time points with the exception of 2 hours in the ISO protocol and the transfer method. Using our novel droplet method, no differences between placebo and active surfaces were detected. The surface in development demonstrated variable activity depending on method, organism, and time point. The ISO demonstrated minimal activity at 2 hours but significant activity at 24 hours (mean 4.5 Log10 CFU/ml difference versus placebo). The ASTEM protocol exhibited significant differences in recovery of staphylococci (mean 5 Log10 CFU/ml) but not Gram-negative isolates (10 fold decrease). Minimal activity was observed with this film in the transfer method. Conclusions Varying results between protocols suggested that efficacy of antimicrobial surfaces cannot be easily and reproducibly compared. Clinical use should be considered and further development of representative methods is needed. PMID:27494336

In vitro antimicrobial activity of five essential oils on multidrug resistant Gram-negative clinical isolates

PubMed Central

Sakkas, Hercules; Gousia, Panagiota; Economou, Vangelis; Sakkas, Vassilios; Petsios, Stefanos; Papadopoulou, Chrissanthy

2016-01-01

Aim/Background: The emergence of drug-resistant pathogens has drawn attention on medicinal plants for potential antimicrobial properties. The objective of the present study was the investigation of the antimicrobial activity of five plant essential oils on multidrug resistant Gram-negative bacteria. Materials and Methods: Basil, chamomile blue, origanum, thyme, and tea tree oil were tested against clinical isolates of Acinetobacter baumannii (n = 6), Escherichia coli (n = 4), Klebsiella pneumoniae (n = 7), and Pseudomonas aeruginosa (n = 5) using the broth macrodilution method. Results: The tested essential oils produced variable antibacterial effect, while Chamomile blue oil demonstrated no antibacterial activity. Origanum, Thyme, and Basil oils were ineffective on P. aeruginosa isolates. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration values ranged from 0.12% to 1.50% (v/v) for tea tree oil, 0.25-4% (v/v) for origanum and thyme oil, 0.50% to >4% for basil oil and >4% for chamomile blue oil. Compared to literature data on reference strains, the reported MIC values were different by 2SD, denoting less successful antimicrobial activity against multidrug resistant isolates. Conclusions: The antimicrobial activities of the essential oils are influenced by the strain origin (wild, reference, drug sensitive, or resistant) and it should be taken into consideration whenever investigating the plants’ potential for developing new antimicrobials. PMID:27366345

Antimicrobial activity of Bryum argenteum.

PubMed

Sabovljevic, Aneta; Sokovic, Marina; Sabovljevic, Marko; Grubisic, Dragoljub

2006-02-01

The antimicrobial activity of Bryum argenteum ethanol extracts was evaluated by microdilution method against four bacterial (Escherichia coli, Bacillus subtilis, Micrococcus luteus and Staphilococcus aureus) and four fungal species (Aspergillus niger, Penicillium ochrochloron, Candida albicans and Trichophyton mentagrophyes). All the investigated ethanol extracts have been proved to be active against all bacteria and fungi tested.

Genomic and functional techniques to mine the microbiome for novel antimicrobials and antimicrobial resistance genes.

PubMed

Adu-Oppong, Boahemaa; Gasparrini, Andrew J; Dantas, Gautam

2017-01-01

Microbial communities contain diverse bacteria that play important roles in every environment. Advances in sequencing and computational methodologies over the past decades have illuminated the phylogenetic and functional diversity of microbial communities from diverse habitats. Among the activities encoded in microbiomes are the abilities to synthesize and resist small molecules, yielding antimicrobial activity. These functions are of particular interest when viewed in light of the public health emergency posed by the increase in clinical antimicrobial resistance and the dwindling antimicrobial discovery and approval pipeline, and given the intimate ecological and evolutionary relationship between antimicrobial biosynthesis and resistance. Here, we review genomic and functional methods that have been developed for accessing the antimicrobial biosynthesis and resistance capacity of microbiomes and highlight outstanding examples of their applications. © 2016 New York Academy of Sciences.

Crude Extract from Ziziphus Jujuba Fruits, a Weapon against Pediatric Infectious Disease

PubMed Central

Daneshmand, F; Zare-Zardini, H; Tolueinia, B; Hasani, Z; Ghanbari, T

2013-01-01

Background Pediatric infectious disease is one of the main problems in cancerous children that treat by chemotherapy drugs. Thus, study in this regard is necessary. The aim of this study was to evaluate antimicrobial properties of ethanolic extract of Ziziphus Jujuba fruits against different infectious pathogens. Materials and Methods This study is descriptive. In vitro antimicrobial activity of extract was assessed on gram negative and gram positive bacteria as well as fungi. The antimicrobial activity was tested by Radial Diffusion Assay (RDA) and Minimal Inhibitory Concentration (MIC) methods. Results The results showed a wide antimicrobial activity of the extract against the microbes studied. Escherichia coli was the most susceptible to the extracts among tested microorganisms for which the MIC was 0.65±0.22 mg/ml. Amongst the bacterial strains investigated, Staphylococcus aureus was the most resistant strain with MIC of 2.26±0.68 mg/ml. The ethanolic extract also showed antimicrobial activity on the fungi studied as no growth was observed in 2.35±0.38 and 2.86±0.7 mg/ml concentration for Candida albicans and Aspergillus fumigatus, respectively. The results of qualitive and quantitative test are well indicative of the extract effective activity against the microbes mentioned. Conclusion Confirming the potential antimicrobial activities of crude extract of Ziziphus Jujuba fruits, this study suggested that ethanolic extracts of this plant is appropriate candidate for treatment of microbial infections, especially pediatric infectious diseases. PMID:24575267

Synergistic effects of guanidine-grafted CMC on enhancing antimicrobial activity and dry strength of paper.

PubMed

Liu, Kai; Xu, Yaoguang; Lin, Xinxing; Chen, Lihui; Huang, Liulian; Cao, Shilin; Li, Jian

2014-09-22

In order to improve the strength property and antimicrobial activity of paper simultaneously, we prepared a novel multifunctional agent based on carboxymethyl cellulose (CMC) by a simple two-stage method. The first stage was the oxidation of CMC to obtain the dialdehyde CMC (DCMC), and the second stage was the graft of guanidine hydrochloride (GH) onto DCMC to obtain DCMC-GH polymer. The strength property and antimicrobial activity of DCMC-GH-coated copy paper have been studied by the tensile test and inhibition zone method, respectively. The results showed that the dry strength index could increase about 20% after the paper was coated with DCMC-GH. The coating of DCMC-GH on paper also resulted in excellent antimicrobial activities against Escherichia coli and Staphylococcus aureus, and the inhibition zone became larger as the GH content grafted on DCMC increased. The novel DCMC-GH polymer would be a multifunctional coating agent for food packaging paper. Copyright © 2014 Elsevier Ltd. All rights reserved.

Antimicrobial agent-free hybrid cationic starch/sodium alginate polyelectrolyte films for food packaging materials.

PubMed

Şen, Ferhat; Uzunsoy, İrem; Baştürk, Emre; Kahraman, Memet Vezir

2017-08-15

This study aimed to develop polyelectrolyte structured antimicrobial food packaging materials that do not contain any antimicrobial agents. Cationic starch was synthesized and characterized by FT-IR spectroscopy and 1 H NMR spectroscopy. Its nitrogen content was determined by Kjeldahl method. Polyelectrolyte structured antimicrobial food packaging materials were prepared using starch, cationic starch and sodium alginate. Antimicrobial activity of materials was defined by inhibition zone method (disc diffusion method). Thermal stability of samples was evaluated by TGA and DSC. Hydrophobicity of samples was determined by contact angle measurements. Surface morphology of samples was investigated by SEM. Moreover, gel contents of samples were determined. The obtained results prove that produced food packaging materials have good thermal, antimicrobial and surface properties, and they can be used as food packaging material in many industries. Copyright © 2017 Elsevier Ltd. All rights reserved.

Antimicrobial silver: An unprecedented anion effect

PubMed Central

Swathy, J. R.; Sankar, M. Udhaya; Chaudhary, Amrita; Aigal, Sahaja; Anshup; Pradeep, T.

2014-01-01

Silver is an indispensable metal but its use has to be minimised for sustainable growth. Much of the silver lost during use is unrecoverable; an example being its use as an antimicrobial agent, a property known since ages. While developing methods to create an affordable drinking water purifier especially for the developing world, we discovered that 50 parts per billion (ppb) of Ag+ released continuously from silver nanoparticles confined in nanoscale cages is enough to cause antimicrobial activity in conditions of normal water. Here we show that the antibacterial and antiviral activities of Ag+ can be enhanced ~1,000 fold, selectively, in presence of carbonate ions whose concentration was maintained below the drinking water norms. The protective layers of the organisms were affected during the carbonate-assisted antimicrobial activity. It is estimated that ~1,300 tons of silver can be saved annually using this new way to enhance its antimicrobial activity. PMID:25418185

Antioxidant, antimicrobial and toxicological properties of Schinus molle L. essential oils.

PubMed

Martins, Maria do Rosário; Arantes, Silvia; Candeias, Fátima; Tinoco, Maria Teresa; Cruz-Morais, Júlio

2014-01-01

Schinus molle L. has been used in folk medicine as antibacterial, antiviral, topical antiseptic, antifungal, antioxidant, anti-inflammatory, anti-tumoural as well as antispasmodic and analgesic; however, there are few studies of pharmacological and toxicological properties of Schinus molle essential oils. The aim of this study was to evaluate the antioxidant and antimicrobial activities of Schinus molle leaf and fruit essential oils, correlated with their chemical composition and evaluate their acute toxicity. The chemical composition of Schinus molle leaf and fruit essential oils were evaluated by GC-FID and GC-MS. Antioxidant properties were determined using the 2,2-diphenyl-1-picryl-hydrazyl (DPPH) free radical and β-carotene/linoleic acid methods. Antimicrobial properties were evaluated by the agar disc diffusion method and minimal inhibitory concentration assay. Toxicity in Artemia salina and acute toxicity with behavioural screening in mice were evaluated. The dominant compounds found in leaf and fruit essential oils (EOs) were monoterpene hydrocarbons, namely α-phellandrene, β-phellandrene, β-myrcene, limonene and α-pinene. EOs showed low scavenging antioxidant activity by the DPPH free radical method and a higher activity by the β-carotene/linoleic acid method. Antimicrobial activity of EOs was observed for Gram+, Gram- pathogenic bacteria and food spoilage fungi. EOs showed totoxicity for Artemia salina and lower toxicity in Swiss mice. The result showed that EOs of leaves and fruits of Schinus molle demonstrated antioxidant and antimicrobial properties, suggesting their potential use in food or pharmaceutical industries. © 2013 Published by Elsevier Ireland Ltd.

Highly Stable Graphene-Based Nanocomposite (GO-PEI-Ag) with Broad-Spectrum, Long-Term Antimicrobial Activity and Antibiofilm Effects.

PubMed

Zhao, Rongtao; Kong, Wen; Sun, Mingxuan; Yang, Yi; Liu, Wanying; Lv, Min; Song, Shiping; Wang, Lihua; Song, Hongbin; Hao, Rongzhang

2018-05-30

Various silver nanoparticle (AgNP)-decorated graphene oxide (GO) nanocomposites (GO-Ag) have received increasing attention owing to their antimicrobial activity and biocompatibility; however, their aggregation in physiological solutions and the generally complex synthesis methods warrant improvement. This study aimed to synthesize a polyethyleneimine (PEI)-modified and AgNP-decorated GO nanocomposite (GO-PEI-Ag) through a facile approach through microwave irradiation without any extra reductants and surfactants; its antimicrobial activity was investigated on Gram-negative/-positive bacteria (including drug-resistant bacteria) and fungi. Compared with GO-Ag, GO-PEI-Ag acquired excellent stability in physiological solutions and electropositivity, showing substantially higher antimicrobial efficacy. Moreover, GO-PEI-Ag exhibited particularly excellent long-term effects, presenting no obvious decline in antimicrobial activity after 1 week storage in physiological saline and repeated use for three times and the lasting inhibition of bacterial growth in nutrient-rich culture medium. In contrast, GO-Ag exhibited a >60% decline in antimicrobial activity after storage. Importantly, GO-PEI-Ag effectively eliminated adhered bacteria, thereby preventing biofilm formation. The primary antimicrobial mechanisms of GO-PEI-Ag were evidenced as physical damage to the pathogen structure, causing cytoplasmic leakage. Hence, stable GO-PEI-Ag with robust, long-term antimicrobial activity holds promise in combating public-health threats posed by drug-resistant bacteria and biofilms.

Isolation and identification of local bacteria endophyte and screening of its antimicrobial property against pathogenic bacteria and fungi

NASA Astrophysics Data System (ADS)

Fikri, Ahmad Syairazie Ibrahim; Rahman, Irman Abdul; Nor, Norefrina Shafinaz Md; Hamzah, Ainon

2018-04-01

Endophytes are organisms, often fungi and bacteria that live in living plant cells. These organisms reside in the living tissues of the host plant in a variety of relationships, ranging from symbiotic to slightly pathogenic. The endophytes may produce a plethora of substances that have potential to be used in modern medicine, agriculture and industry. The aims of this study are to isolate, identify and screening antimicrobial activity of bacterial endophytes. The endophytes were isolated using nutrient agar, incubated at 37°C for 48 hours. Identification of the isolates were done based on morphological characteristics, biochemical tests and 16S rDNA molecular analysis. Disk diffusion method was used to screen for antimicrobial activity of metabolites from endophytes against pathogenic bacteria. Screening for antifungal activity of selected endophytes was done using dual culture method againts pathogenic fungi followed by Kirby-Bauer method. Results showed endophytes designated as B2c and B7b have positive antimicrobial activity. The metabolites from isolate B2c showed antimicrobial activity against pathogenic bacteria methicillin-resistant Staphylococcus aureus (MRSA), Staphylococcus aureus and Staphylococcus epidermis, while isolate B7b have positive activities againts MRSA, S. aureus and Pseudomonas aeruginosa. Isolates B2c displayed antifungal activity against Fusarium oxysporum, Fusarium solani, Phytophthora palmivora and Colletotrichum gloeosporioides. Identification using biochemical tests and 16S rDNA sequences identified isolate B2c as Pseudomonas resinovorans with 97% homology and isolate B7b as Bacillus subtilis with 98% homology.

Inorganic antimicrobial coating for titanium alloy and its effect on bacteria.

PubMed

Tamai, Katsuya; Kawate, Kenji; Kawahara, Ikuo; Takakura, Yoshinori; Sakaki, Kazuhiko

2009-03-01

For orthopedic implants, infection is a serious problem. Therefore, we considered an implant with antimicrobial ability can prevent infection. We tried to coat a titanium alloy surface with Novaron, a commercially available inorganic antimicrobial. The purpose of this study was to analyze the differences among the surfaces of materials coated using different processing pressures of the working gas and analysis of the antimicrobial activity. One of the inorganic antimicrobials Novaron (grade VZ 600) was applied to titanium alloy (Ti6Al4V) plates. This antimicrobial has limited heat resistance, so we used cold spray technology to coat the titanium alloy with it. The principle of cold spray technology is spraying a powder in a high-velocity gas jet, accelerated by adiabatic expansion, against a substrate. Scanning electron microscopy (SEM) and energy dispersive X-ray spectrometry (EDS) were used to analyze the differences among the surfaces of materials coated using different processing pressures of the working gas. The Japanese Industrial Standard (JIS) method (JIS Z2801: 2000) was used to analyze the antimicrobial activity against Staphylococcus aureus, Pseudomonas aeruginosa, and Klebsiella pneumoniae. Antimicrobial activity was analyzed only for the sample coated at 3.0 MPa. The SEM and EDS results indicated that when the pressure of the working gas was increased, the antimicrobial coated the titanium adequately. This material showed good effects against S. aureus and P. aeruginosa and some effect for K. pneumoniae. Antimicrobial implants represent a preventive method against infection. There is a possibility of using them not only for clean operations but also for operations with suspected bacterial contamination, such as fixation of slight compound fractures.

Synthesis and anti-microbial activity of hydroxylammonium ionic liquids.

PubMed

Ismail Hossain, M; El-Harbawi, Mohanad; Noaman, Yousr Abdulhadi; Bustam, Mohd Azmi B; Alitheen, Noorjahan Banu Mohamed; Affandi, Nor Azrin; Hefter, Glenn; Yin, Chun-Yang

2011-06-01

Eight hydroxylammonium-based room temperature ionic liquids (ILs) have been synthesized by acid-base neutralization of ethanolamines with organic acids. The ILs were characterized by infrared and nuclear magnetic resonance spectroscopies and elemental analysis. Their anti-microbial activities were determined using the well-diffusion method. All eight ILs were toxic to Staphylococcus aureus, while 2-hydroxyethylammonium lactate and 2-hydroxy-N-(2-hydroxyethyl)-N-methylethanaminium acetate showed high anti-microbial activity against a wide range of human pathogens. Crown Copyright © 2011. Published by Elsevier Ltd. All rights reserved.

Silanols, a New Class of Antimicrobial Agent

DTIC Science & Technology

2006-04-01

carbinols against the four bacteria was log (1/MLC) = 0.670 log P + 0.0035 ∆ν -1.836, n = 282, r = 0.96, s = 0.22. This equation and a significantly...activity relationship of antimicrobial agents by means of equations [8] based on a method proposed by Hansch and Fujita in 1964 [1]. This multiple...correlation equations between their antimicrobial activities and structural properties, log P and H-bond acidity, were created by a multiple regression

Phytochemical characterization, antimicrobial activity and reducing potential of seed oil, latex, machine oil and presscake of Jatropha curcas

PubMed Central

Sharma, Amit Kumar; Gangwar, Mayank; Kumar, Dharmendra; Nath, Gopal; Kumar Sinha, Akhoury Sudhir; Tripathi, Yamini Bhushan

2016-01-01

Objective: This study aims to evaluate the antimicrobial activity, phytochemical studies and thin layer chromatography analysis of machine oil, hexane extract of seed oil and methanol extract of presscake & latex of Jatropha curcas Linn (family Euphorbiaceae). Materials and Methods: J. curcas extracts were subjected to preliminary qualitative phytochemical screening to detect the major phytochemicals followed by its reducing power and content of phenol and flavonoids in different fractions. Thin layer chromatography was also performed using different solvent systems for the analysis of a number of constituents in the plant extracts. Antimicrobial activity was evaluated by the disc diffusion method, while the minimum inhibitory concentration, minimum bactericidal concentration and minimum fungicidal concentration were calculated by micro dilution method. Results: The methanolic fraction of latex and cake exhibited marked antifungal and antibacterial activities against Gram-positive and Gram-negative bacteria. Phytochemical analysis revealed the presence of alkaloids, saponins, tannins, terpenoids, steroids, glycosides, phenols and flavonoids. Reducing power showed dose dependent increase in concentration compared to standard Quercetin. Furthermore, this study recommended the isolation and separation of bioactive compounds responsible for the antibacterial activity which would be done by using different chromatographic methods such as high-performance liquid chromatography (HPLC), GC-MS etc. Conclusion: The results of the above study suggest that all parts of the plants possess potent antibacterial activity. Hence, it is important to isolate the active principles for further testing of antimicrobial and other biological efficacy. PMID:27516977

GC-MS analysis and antimicrobial activity determination of Citrus medica L. var proper leaf essential oil from South Sulawesi against skin pathogen microorganism

NASA Astrophysics Data System (ADS)

Aliyah; Himawan, A.; Rante, H.; Mufidah; Ningsih, D. R.

2017-11-01

A research about Citrus medica L. var sarcodactylis had been conducted and it showed a significant antimicrobial activity, thus drive our curiosity to investigate the other variety from the same species, Citrus medica L. var proper. This research focuses in chemical compound study and antimicrobial activity screening against Staphylococcus aureus, Propionibacterium acne, and Candida albicans of Citrus medica L. var Proper leaves’ essential oil. The essential oil is distillated from fresh leaves by hydrodestillation. The chemical compound was analysed using GC-MS instrument while the antimicrobial activity was tested using disk diffusion method. The results showed that the major component of the essential oil was Z-citral, citral and limonene compounds. The antimicrobial activity test results against the test microorganism are 9.15±0.15 mm, 11.15±1.3 mm and 8.02±0.48 mm, consecutively, for Staphylococcus aureus, Propionibacterium acne and Candida albicans.

Antimicrobial activities of bacteriocins E50-52 and B602 against MRSA and other nosocomial infections

USDA-ARS?s Scientific Manuscript database

Our objective was to determine the antimicrobial activities of previously published bacteriocins E50-52 and B602 against methicillin resistant Staphylococcus aureus (MRSA) and other prominent nosocomial bacterial infections. methods: Several Russian hospitals were enlisted into the study from 2003 ...

In vitro Antimicrobial Activity of Traditional Plant Used in Mestizo Shamanism from the Peruvian Amazon in Case of Infectious Diseases

PubMed Central

Roumy, Vincent; Gutierrez-Choquevilca, Andréa-Luz; Lopez Mesia, Jean Pierre; Ruiz, Lastenia; Ruiz Macedo, Juan Celidonio; Abedini, Amin; Landoulsi, Ameni; Samaillie, Jennifer; Hennebelle, Thierry; Rivière, Céline; Neut, Christel

2015-01-01

Context: Our survey was performed near Iquitos (Peruvian Amazon) and its surroundings and leads us to consider Mestizo ethnomedical practices. The plant species reported here are traditionally used for ailments related to microbial infections. Inhabitants of various ethnic origins were interviewed, and 52 selected plants extracts were evaluated for their antimicrobial properties against a panel of 36 sensitive and multi-resistant bacteria or yeast. The study aimed at providing information on antimicrobial plant extract activities and the ethnomedical context of Mestizo riverine populations from Loreto (Peru). Material and Method: The minimum inhibitory concentrations (MICs) of the plant crude extracts were carried out using the agar dilution method and ranged between 0.075 and 5.0 mg/ml. Results: Of the 40 plants analyzed, 9 species showed MIC ≤0.3 mg/ml (Anacardium occidentale, Couroupita guianensis, Croton lechleri, Davilla rugosa, Erythrina amazonica, Jacaranda copaia subsp. Spectabilis, Oenocarpus bataua, Peperomia macrostachya, and Phyllanthus urinaria) for one or several of the 36 microorganisms and only 6 drug extracts were inactive. Among the 40 plants, 13 were evaluated for the first time for an antibacterial activity. Conclusion: This evaluation of the antimicrobial activity of 40 plants using an approved standard methodology allowed comparing those activities against various microbes to establish antimicrobial spectra of standardized plant extracts, and give support to the traditional use of these plants. It may also help discovering new chemical classes of antimicrobial agents that could serve against multi-resistant bacteria. SUMMARY This study leads us to consider Mestizo ethnomedical practices near Iquitos (Peruvian Amazon) and its surroundings. The plant species reported here are traditionally used for ailments related to microbial infections. 52 selected plants extracts were evaluated for their antimicrobial properties against a panel of 36 sensitive and multi resistant bacteria or yeast. The study aimed at providing information on antimicrobial plant extract activities and the ethnomedical context of Mestizo riverine populations from Loreto. PMID:27013805

In vitro antimicrobial activities of cinnamon bark oil, anethole, carvacrol, eugenol and guaiazulene against Mycoplasma hominis clinical isolates.

PubMed

Sleha, Radek; Mosio, Petra; Vydrzalova, Marketa; Jantovska, Alexandra; Bostikova, Vanda; Mazurova, Jaroslava

2014-06-01

The aim of this study was to evaluate the antimicrobial effects of five natural substances against 50 clinical isolates of Mycoplasma hominis. The in vitro activity of selected natural compounds, cinnamon bark oil, anethole, carvacrol, eugenol and guaiazulene, was investigated against 50 M. hominis isolates cultivated from cervical swabs by the broth dilution method. All showed valuable antimicrobial activity against the tested isolates. Oil from the bark of Cinnamomum zeylanicum (MBC90 = 500 µg/mL) however was found to be the most effective. Carvacrol (MBC90 = 600 µg/mL) and eugenol (MBC90 = 1000 µg/mL) also possessed strong antimycoplasmal activity. The results indicate that cinnamon bark oil, carvacrol and eugenol have strong antimycoplasmal activity and the potential for use as antimicrobial agents in the treatment of mycoplasmal infections.

Cytotoxic and antimicrobial activities of endophytic fungi isolated from Bacopa monnieri (L.) Pennell (Scrophulariaceae).

PubMed

Katoch, Meenu; Singh, Gurpreet; Sharma, Sadhna; Gupta, Nidhi; Sangwan, Payare Lal; Saxena, Ajit Kumar

2014-02-11

Endophytes, which reside in plant tissues, have the potential to produce novel metabolites with immense benefits for health industry. Cytotoxic and antimicrobial activities of endophytic fungi isolated from Bacopa monnieri (L.) Pennell were investigated. Endophytic fungi were isolated from the Bacopa monnieri. Extracts from liquid cultures were tested for cytotoxicity against a number of cancer cell lines using the MTT assay. Antimicrobial activity was determined using the micro dilution method. 22% of the examined extracts showed potent (IC50 of <20 μg/ml) cytotoxic activity against HCT-116 cell line. 5.5%, 11%, 11% of the extracts were found to be cytotoxic for MCF-7, PC-3, and A-549 cell lines respectively. 33% extracts displayed antimicrobial activity against at least one test organism with MIC value 10-100 μg/ml. The isolate B9_Pink showed the most potent cytotoxic activity for all the cell lines examined and maximum antimicrobial activity against the four pathogens examined which was followed by B19. Results indicated the potential for production of bioactive agents from endophytes of Bacopa monnieri.

Antimicrobial activity and safety evaluation of Enterococcus faecium KQ 2.6 isolated from peacock feces.

PubMed

Zheng, Wei; Zhang, Yu; Lu, Hui-Min; Li, Dan-Ting; Zhang, Zhi-Liang; Tang, Zhen-Xing; Shi, Lu-E

2015-05-12

The objective of this paper was to study antimicrobial activity and safety of Enterococcus faecium KQ 2.6 (E. faecium KQ 2.6) isolated from peacock feces. Agar well diffusion method was adopted in antimicrobial activity assay. Disk diffusion test was used to determine the antibiotic resistance. The identification and virulence potential of E. faecium KQ 2.6 were investigated using PCR amplification. The results indicated that cell free supernatant (CFS) of the strain had the good antimicrobial activity against selected gram-positive and gram-negative bacteria. The biochemical characteristics of antimicrobial substances were investigated. The results indicated that the antimicrobial substances were still active after treatment with catalase and proteinase, respectively. Moreover, the stability of antimicrobial substances did not change after heat treatment at 40, 50, 60, 70 and 80°C for 30 min, respectively. The activity of antimicrobial substances remained stable at 4 and -20°C after long time storage. The antimicrobial activity of CFS was compared with that of the buffer with similar strength and pH. The inhibitory zone of the buffer was apparently smaller than that of CFS, which meant that the acid in CFS was not the only factor that was contributed to antibacterial activity of CFS. The antibiotic resistance and virulence potential were evaluated using disk diffusion test and PCR amplification. The results showed that E. faecium KQ 2.6 did not harbor any tested virulence genes such as gelE, esp, asa1, cylA, efaA and hyl. It was susceptible to most of tested antibiotics except for vancomycin and polymyxin B. E. faecium KQ 2.6 may be used as bio-preservative cultures for the production of fermented foods.

Evaluation of antimicrobial properties of cork.

PubMed

Gonçalves, Filipa; Correia, Patrícia; Silva, Susana P; Almeida-Aguiar, Cristina

2016-02-01

Cork presents a range of diverse and versatile properties making this material suitable for several and extremely diverse industrial applications. Despite the wide uses of cork, its antimicrobial properties and potential applications have deserved little attention from industry and the scientific community. Thus, the main purpose of this work was the evaluation of the antibacterial properties of cork, by comparison with commercially available antimicrobial materials (Ethylene-Vinyl Acetate copolymer and a currently used antimicrobial commercial additive (ACA)), following the previous development and optimization of a method for such antimicrobial assay. The AATCC 100-2004 standard method, a quantitative procedure developed for the assessment of antimicrobial properties in textile materials, was used as reference and optimized to assess cork antibacterial activity. Cork displayed high antibacterial activity against Staphylococcus aureus, with a bacterial reduction of almost 100% (96.93%) after 90 minutes of incubation, similar to the one obtained with ACA. A more reduced but time-constant antibacterial action was observed against Escherichia coli (36% reduction of the initial number of bacterial colonies). To complement this study, antibacterial activity was further evaluated for a water extract of cork and an MIC of 6 mg mL(-1) was obtained against the reference strain S. aureus. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

A comparative study of the antioxidant, antimicrobial, cytotoxic and thrombolytic potential of the fruits and leaves of Spondias dulcis

PubMed Central

Islam, Shawkat Md. Aminul; Ahmed, Kh Tanvir; Manik, Mohammad Kawsar; Wahid, Md. Arif; Kamal, Chowdhury Shafayat Ibne

2013-01-01

Objective To investigate the antioxidant, antimicrobial, cytotoxic and thrombolytic property of the fruits and leaves of Spondias dulcis (S. dulcis). Methods Methanolic extracts of fruits and leaves of S. dulcis were partitioned with chloroform and dichloromethane. The antioxidant potential of the crude extract and partitioned fractions were evaluated in terms of total phenolic content, total flavonoid content, DPPH radical scavenging potential, reducing potential and total antioxidant capacity by specific standard procedures. The antimicrobial activity was evaluated using disc diffusion method. The cytotoxicity was evaluated by using brine shrimp lethality bioassay and compared with vincristine sulfate. The thrombolytic activity was compared with streptokinase. Results The methanolic fruit extract exhibited the highest phenolic content, flavonoid content and antioxidant capacity, among the other extracts, with the highest DPPH radical scavenging activity at a concentration of 10 µg/mL (IC50: 1.91 µg/mL) and maximum reducing power at a concentration of 100 µg/mL (EC50: 3.58 µg/mL). Though all extract showed moderate antimicrobial activity against the bacterial strains, weak or no activity against fungus. The range of LC50 value of all extracts was 1.335-14.057 µg/mL which was far lower than the cut off index for cytotoxicity. All extracts exhibited statistically significant (P<0.001) thrombolytic activity. Conclusions Our study suggested that S. dulcis exhibits antimicrobial activities against a wide variety of strains while it possesses significant antioxidant, cytotoxic and thrombolytic activity. PMID:23998007

Antimicrobial activity of methanolic extracts of Sambucus ebulus and Urtica dioica against clinical isolates of methicillin resistant Staphylococcus aureus.

PubMed

Salehzadeh, Ali; Asadpour, Leila; Naeemi, Akram Sadat; Houshmand, Elham

2014-01-01

Increase in the emergence of drug -resistant pathogens led to the development of natural antimicrobials. In this study the antimicrobial effect of methanolic extracts of Sambucus ebulus and Urtica dioica on 16 skin and wound infections isolates of methicillin resistant S. aureus have been studied. Solvent extraction procedure was done using soxhlet apparatus for extracting antimicrobial agents from freeze dried plants. Antibacterial activity was measured using agar well diffusion method. The MIC of Sambucus ebulus and Urtica dioica extracts against the standard strain of S. aureus ATCC 6538 were determined using the micro dilution method at 15 mg and 20 mg respectively. All the test bacteria were found sensitive to the Sambucus ebulus extract and only one isolate was resistant to Urtica dioica extract. Extracts of Sambucus ebulus and Urtica dioica possess antibacterial potency against MRSA isolates and may be used as a natural antiseptics and antimicrobial agents in medicine.

Antimicrobial activity of bark extracts of Syzygium jambos (L.) alston (Myrtaceae).

PubMed

Djipa, C D; Delmée, M; Quetin-Leclercq, J

2000-07-01

Syzygium jambos (L.) Alston (Myrtaceae) is a widespread medicinal plant traditionally used in sub-Saharan Africa to treat infectious diseases. Acetone and aqueous extracts from the bark of S. jambos were tested for antimicrobial activity in vitro by the agar dilution method in petri dishes. Both extracts showed some activity against the tested micro-organisms. They proved to be particularly effective on Staphylococcus aureus, Yersinia enterocolitica and coagulase negative staphylococci among which Staphylococcus hominis, Staphylococcus cohnii and Staphylococcus warneri. These properties seem to be related to the high tannin content of S. jambos extracts (77 and 83% for the aqueous and acetone extracts, respectively, determined according to the European Pharmacopoeia method) which were generally more active than Hamamelis virginiana, Krameria triandra, Alchemilla vulgaris and Rubus fruticosus extracts containing 48, 44, 46 and 28% tannins, respectively. Furthermore, elimination of tannins totally suppressed these antimicrobial activities.

Bioactive molecules in Kalanchoe pinnata leaves: extraction, purification, and identification.

PubMed

El Abdellaoui, Saïda; Destandau, Emilie; Toribio, Alix; Elfakir, Claire; Lafosse, Michel; Renimel, Isabelle; André, Patrice; Cancellieri, Perrine; Landemarre, Ludovic

2010-10-01

Kalanchoe pinnata (Lam.) Pers. (syn. Bryophyllum pinnatum; family Crassulaceae) is a popular plant used in traditional medicine in many temperate regions of the world and particularly in South America. In Guyana, the leaves are traditionally used as an anti-inflammatory and antiseptic to treat coughs, ulcers, and sores. The purpose of this study was to implement a method for targeting and identifying molecules with antimicrobial activity, which could replace chemical preservatives in cosmetic applications. The leaves were extracted by a method based on pressurized liquid extraction (PLE), using different solvents. A study of antimicrobial activity and cytotoxicity tests were performed to select the most interesting extract. To isolate one or more active molecules, the selected crude extract was fractionated by centrifugal partition chromatography (CPC) and then antimicrobial activity and cytotoxicity of each fraction were tested under the same procedure. The last step consisted of identifying the main compounds in the most active fraction by LC-MS/MS.

An in vitro antibacterial study of savory essential oil and geraniol in combination with standard antimicrobials.

PubMed

Miladinović, Dragoljub L; Ilić, Budimir S; Kocić, Branislava D; Miladinović, Marija D

2014-11-01

The chemical composition and antibacterial activity of Satureja kitaibelii Wierzb. ex Heuff. (savory) essential oil were examined, as well as the association between it and standard antimicrobials: tetracycline and chloramphenicol. The antibacterial activities of geraniol, the main constituent of S. kitaibelii oil, individually and in combination with standard antimicrobials were also determined. The interactions of the essential oil and geraniol with antimicrobials toward five selected strains were evaluated using the microdilution checkerboard assay in combination with chemometric methods. Oxygenated monoterpenes were the most abundant compound class in the oil (59.7%), with geraniol (50.4%) as the major compound. The essential oil exhibited in vitro antibacterial activity against all tested bacterial strains, but the activities were lower than those of the standard antimicrobials. The combinations savory oil-chloramphenicol, savory oil-tetracycline and geraniol-chloramphenicol produced predominantly synergistic interactions (FIC indices in the range 0.21-0.87) and substantial reductions in the MIC values of antimicrobials against Gram-negative bacteria, the pharmacological treatment of which is very difficult nowadays. In the PCA and HCA analyses these combinations form a separate group.

Impact of pectin esterification on the antimicrobial activity of nisin-loaded pectin particles.

PubMed

Krivorotova, Tatjana; Staneviciene, Ramune; Luksa, Juliana; Serviene, Elena; Sereikaite, Jolanta

2017-01-01

The relationship between pectin structure and the antimicrobial activity of nisin-loaded pectin particles was examined. The antimicrobial activity of five different nisin-loaded pectin particles, i.e., nisin-loaded high methoxyl pectin, low methoxyl pectin, pectic acid, dodecyl pectin with 5.4 and 25% degree of substitution were tested in the pH range of 4.0-7.0 by agar-diffusion assay and agar plate count methods. It was found that the degree of esterification of carboxyl group of galacturonic acid in pectin molecule is important for the antimicrobial activity of nisin-loaded pectin particles. Nisin-loaded particles prepared using pectic acid or the pectin with low degree of esterification exhibit higher antimicrobial activity than nisin-loaded high methoxyl pectin particles. Pectins with free carboxyl groups or of low degree of esterification are the most suitable for particles preparation. Moreover, nisin-loaded pectin particles were active at close to neutral or neutral pH values. Therefore, they could be effectively applied for food preservation. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 33:245-251, 2017. © 2016 American Institute of Chemical Engineers.

Antimicrobial and healing activity of kefir and kefiran extract.

PubMed

Rodrigues, Kamila Leite; Caputo, Lucélia Rita Gaudino; Carvalho, Jose Carlos Tavares; Evangelista, João; Schneedorf, Jose Maurício

2005-05-01

Kefir and its insoluble polysaccharide, kefiran, were both tested for antimicrobial and cicatrizing activities against several bacterial species and Candida albicans using an agar diffusion method. Comparator antimicrobials were also tested. Cicatrizing experiments were carried out on Wistar rats with induced skin lesions and Staphylococcus aureus inoculation, using a topical application of a 70% kefir gel. Both kefir and kefiran showed some activity against all organisms tested; the highest activity was against Streptococcus pyogenes. Cicatrizing experiments using 70% kefir gel had a protective effect on skin connective tissue and 7 days treatment enhanced wound healing compared with 5 mg/kg of neomycin-clostebol emulsion.

Synthesis and Evaluation of Ester Derivatives of 10-Hydroxycanthin-6-one as Potential Antimicrobial Agents.

PubMed

Zhao, Fei; Dai, Jiang-Kun; Liu, Dan; Wang, Shi-Jun; Wang, Jun-Ru

2016-03-21

As part of our continuing research on canthin-6-one antimicrobial agents, a new series of ester derivatives of 10-hydroxycanthin-6-one were synthesized using a simple and effective synthetic route. The structure of each compound was characterized by NMR, ESI-MS, FT-IR, UV, and elemental analysis. The antimicrobial activity of these compounds against three phytopathogenic fungi (Alternaria solani, Fusarium graminearum, and Fusarium solani) and four bacteria (Bacillus cereus, Bacillus subtilis, Ralstonia solanacearum, and Pseudomonas syringae) were evaluated using the mycelium linear growth rate method and micro-broth dilution method, respectively. The structure-activity relationship is discussed. Of the tested compounds, 4 and 7s displayed significant antifungal activity against F. graminearum, with inhibition rates of 100% at a concentration of 50 μg/mL. Compounds 5, 7s, and 7t showed the best inhibitory activity against all the tested bacteria, with minimum inhibitory concentrations (MICs) between 3.91 and 31.25 μg/mL. Thus, 7s emerged as a promising lead compound for the development of novel canthine-6-one antimicrobial agents.

Antimicrobial Activity of Thin Solid Films of Silver Doped Hydroxyapatite Prepared by Sol-Gel Method

PubMed Central

Iconaru, Simona Liliana; Chapon, Patrick; Le Coustumer, Philippe; Predoi, Daniela

2014-01-01

In this work, the preparation and characterization of silver doped hydroxyapatite thin films were reported and their antimicrobial activity was characterized. Silver doped hydroxyapatite (Ag:HAp) thin films coatings substrate was prepared on commercially pure Si disks by sol-gel method. The silver doped hydroxyapatite thin films were characterized by various techniques such as Scanning electron microscopy (SEM) with energy Dispersive X-ray attachment (X-EDS), Fourier transform infrared spectroscopy (FT-IR), and glow discharge optical emission spectroscopy (GDOES). These techniques have permitted the structural and chemical characterisation of the silver doped hydroxyapatite thin films. The antimicrobial effect of the Ag:HAp thin films on Escherichia coli and Staphylococcus aureus bacteria was then investigated. This is the first study on the antimicrobial effect of Ag:HAp thin films obtained by sol-gel method. The results of this study have shown that the Ag:HAp thin films with x Ag = 0.5 are effective against E. coli and S. aureus after 24 h. PMID:24523630

Antimicrobial activity of thin solid films of silver doped hydroxyapatite prepared by sol-gel method.

PubMed

Iconaru, Simona Liliana; Chapon, Patrick; Le Coustumer, Philippe; Predoi, Daniela

2014-01-01

In this work, the preparation and characterization of silver doped hydroxyapatite thin films were reported and their antimicrobial activity was characterized. Silver doped hydroxyapatite (Ag:HAp) thin films coatings substrate was prepared on commercially pure Si disks by sol-gel method. The silver doped hydroxyapatite thin films were characterized by various techniques such as Scanning electron microscopy (SEM) with energy Dispersive X-ray attachment (X-EDS), Fourier transform infrared spectroscopy (FT-IR), and glow discharge optical emission spectroscopy (GDOES). These techniques have permitted the structural and chemical characterisation of the silver doped hydroxyapatite thin films. The antimicrobial effect of the Ag:HAp thin films on Escherichia coli and Staphylococcus aureus bacteria was then investigated. This is the first study on the antimicrobial effect of Ag:HAp thin films obtained by sol-gel method. The results of this study have shown that the Ag:HAp thin films with x(Ag) = 0.5 are effective against E. coli and S. aureus after 24 h.

In vitro activity of ABT-492 against anaerobic bacteria.

PubMed

Sillerström, E; Wahlund, E; Nord, C E

2004-06-01

The purpose of the study was to determine the in vitro activity of ABT-492 compared with that of other antimicrobial agents against anaerobic bacteria. The activity of ABT-492 was investigated against 369 clinical isolates of anaerobic bacteria by the agar dilution method and was compared with that of moxifloxacin, piperacillin, cefoxitin, imipenem, clindamycin and metronidazole. ABT-492 and imipenem were the most active antimicrobial agents tested.

Antimicrobial activity and chemical analysis of Microlicia hatschbachii Wurdack (Melastomataceae) extract.

PubMed

Cassiano, Dayse S A; Pacheco, Alessandra G M; da Costa, Mateus M; Almeida, Jackson R G S; Vieira, Ivo J C; Branco, Alexsandro

2014-01-01

Aerial parts of Microlicia hatschbachii were extracted with hexane, and the extract was evaluated for antimicrobial activity by a broth dilution method. After phytochemical procedures: GC-MS identified aliphatic alkanes, carboxylic acids and methyl esters of long-chain fatty acids; and two diterpenoids [labd-8(17)-en-15-oic acid and labd-8(17),13-dien-15-oic acid] were identified by (1)H and (13)C NMR. The antimicrobial activity of the hexane extract could be attributed to the presence of labdanes. This identification is the first reported occurrence of labdane diterpenes in the Melastomataceae family.

In vitro antimicrobial activity of ethanolic fractions of Cryptolepis sanguinolenta

PubMed Central

2012-01-01

Background Following claims that some plants have antimicrobial activities against infectious microbes, the in vitro antimicrobial activities of different solvent fractions of ethanolic extract of Cryptolepis sanguinolenta were evaluated against eight standard bacteria and clinical isolates. Methods The solvent partitioning protocol involving ethanol, petroleum ether, chloroform, ethyl acetate and water, was used to extract various fractions of dried pulverized Cryptolepis sanguinolenta roots. Qualitative phyto-constituents screening was performed on the ethanol extract, chloroform fraction and the water fraction. The Kirby Bauer disk diffusion method was employed to ascertain the antibiogram of the test organisms while the agar diffusion method was used to investigate the antimicrobial properties of the crude plant extracts. The microplate dilution method aided in finding the MICs while the MBCs were obtained by the method of Nester and friends. The SPSS 16.0 version was used to analyze the percentages of inhibitions and bactericidal activities. Results The phytochemical screening revealed the presence of alkaloids, reducing sugars, polyuronides, anthocyanosides and triterpenes. The ethanol extract inhibited 5 out of 8 (62.5%) of the standard organisms and 6 out of 8 (75%) clinical isolates. The petroleum ether fraction inhibited 4 out of 8 (50%) of the standard microbes and 1 out of 8 (12.5%) clinical isolates. It was also observed that the chloroform fraction inhibited the growth of all the organisms (100%). Average inhibition zones of 14.0 ± 1.0 mm to 24.67 ± 0.58 mm was seen in the ethyl acetate fraction which halted the growth of 3 (37.5%) of the standard organisms. Inhibition of 7 (87.5%) of standard strains and 6 (75%) of clinical isolates were observed in the water fraction. The chloroform fraction exhibited bactericidal activity against all the test organisms while the remaining fractions showed varying degrees of bacteriostatic activity. Conclusion The study confirmed that fractions of Cryptolepis sanguinolenta have antimicrobial activity. The chloroform fraction had the highest activity, followed by water, ethanol, petroleum ether and ethyl acetate respectively. Only the chloroform fraction exhibited bactericidal activity and further investigations are needed to ascertain its safety and prospects of drug development. PMID:22709723

Production of Silver Nanoparticles with Strong and Stable Antimicrobial Activity against Highly Pathogenic and Multidrug Resistant Bacteria

PubMed Central

Saeb, Amr T. M.; Alshammari, Ahmad S.; Al-Brahim, Hessa; Al-Rubeaan, Khalid A.

2014-01-01

Aims. To synthesize, characterize, and analyze antimicrobial activity of AgNPs of Escherichia hermannii (SHE), Citrobacter sedlakii (S11P), and Pseudomonas putida (S5). Methods. The synthesized AgNPs were examined using ultraviolet-visible spectroscopy (UV-vis) and, zeta potential, and the size and the morphology obtained from the three different isolates were also confirmed by TEM. Results. Among the three isolates tested, SHE showed the best antimicrobial activity due to the presence of small (4–12 nm) and stable (−22 mV) AgNPs. Stability of AgNPs was also investigated and found to be dependent on the nature of isolates. Conclusion. Produced AgNPs showed particle stability and antimicrobial efficacy up to 90 days of production. Our AgNPs exhibited greater antimicrobial activity compared with gentamicin against P. aeruginosa isolates and vancomycin against S. aureus and MRSA isolates at very low concentration (0.0002 mg per Microliters). PMID:25093206

Antimicrobial and antiplasmid activities of essential oils.

PubMed

Schelz, Zsuzsanna; Molnar, Joseph; Hohmann, Judit

2006-06-01

The antimicrobial and antiplasmid activities of essential oils (orange oil, eucalyptus oil, fennel oil, geranium oil, juniper oil, peppermint oil, rosemary oil, purified turpentine oil, thyme oil, Australian tea tree oil) and of menthol, the main component of peppermint oil, were investigated. The antimicrobial activities were determined on the Gram (+) Staphylococcus epidermidis and the Gram (-) Escherichia coli F'lac K12 LE140, and on two yeast Saccharomyces cerevisiae 0425 delta/1 and 0425 52C strains. The antiplasmid activities were investigated on E. coli F'lac bacterial strain. Each of the oils exhibited antimicrobial activity and three of them antiplasmid action. The interaction of peppermint oil and menthol with the antibiotics was studied on the same bacterial strain with the checkerboard method. Peppermint oil and menthol displayed additive synergy with oxytetracycline. A new mechanism of plasmid curing was established for one of the oil components.

Antimicrobial activity and partial characterization of bacteriocin-like inhibitory substances produced by Lactobacillus spp. isolated from artisanal Mexican cheese.

PubMed

Heredia-Castro, Priscilia Y; Méndez-Romero, José I; Hernández-Mendoza, Adrián; Acedo-Félix, Evelia; González-Córdova, Aarón F; Vallejo-Cordoba, Belinda

2015-12-01

Lactobacillus spp. from Mexican Cocido cheese were shown to produce bacteriocin-like substances (BLS) active against Staphylococcus aureus,Listeria innocua,Escherichia coli, andSalmonella typhimurium by using the disk diffusion method. Crude extracts of Lactobacillus fermentum showed strong inhibitory activity against Staph. aureus, L. innocua, E. coli, and Salmonella cholerae. Complete inactivation of antimicrobial activity was observed after treatment of crude extracts with proteinase K, pronase, papain, trypsin, and lysozyme, confirming their proteinaceous nature. However, antimicrobial activity was partly lost for some of the crude extracts when treated with α-amylase, indicating that carbohydrate moieties were involved. The antimicrobial activity of the crude extracts was stable at 65°C for 30min over a wide pH range (2-8), and addition of potassium chloride, sodium citrate, ethanol, and butanol did not affect antibacterial activity. However, antimicrobial activity was lost after heating at 121°C for 15min, addition of methanol or Tween 80. Fourteen out of 18 Lactobacillus spp. showed antimicrobial activity against different test microorganisms, and 12 presented bacteriocin-like substances. Generation time and growth rate parameters indicated that the antimicrobial activity of crude extracts from 3 different strains was effective against the 4 indicator microorganisms. One of the crude extracts showed inhibition not only against gram-positive but also against gram-negative bacteria. Bacteriocin-like substances produced by this specific Lactobacillus strain showed potential for application as a food biopreservative. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Predictive Model of Linear Antimicrobial Peptides Active against Gram-Negative Bacteria.

PubMed

Vishnepolsky, Boris; Gabrielian, Andrei; Rosenthal, Alex; Hurt, Darrell E; Tartakovsky, Michael; Managadze, Grigol; Grigolava, Maya; Makhatadze, George I; Pirtskhalava, Malak

2018-05-29

Antimicrobial peptides (AMPs) have been identified as a potential new class of anti-infectives for drug development. There are a lot of computational methods that try to predict AMPs. Most of them can only predict if a peptide will show any antimicrobial potency, but to the best of our knowledge, there are no tools which can predict antimicrobial potency against particular strains. Here we present a predictive model of linear AMPs being active against particular Gram-negative strains relying on a semi-supervised machine-learning approach with a density-based clustering algorithm. The algorithm can well distinguish peptides active against particular strains from others which may also be active but not against the considered strain. The available AMP prediction tools cannot carry out this task. The prediction tool based on the algorithm suggested herein is available on https://dbaasp.org.

Antimicrobial and free radical scavenging activities of five Palestinian medicinal plants.

PubMed

Qabaha, Khaled Ibraheem

2013-01-01

Extracts from five indigenous Palestinian medicinal plants including Rosmarinus officinalis, Pisidium guajava, Punica granatum peel, grape seeds and Teucrium polium were investigated for antimicrobial and free radical scavenging activities against eight microorganisms, using well diffusion method. The microorganisms included six bacterial isolates (i.e. Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginos, Klebsiella pneumonia, Bacillus subtilis and Micrococcus luteus) and two fungal isolates (i.e. Candida albicans and Aspergillus niger). A standard antioxidant assay was performed on the plant extracts to assess their capability in scavenging 2,2-diphenyl-1-picrylhydrazyl (DPPH). Of the five tested plant extract, only Rosmarinus offcinalis extract contained significant antimicrobial activity against all eight microbial isolates including Pseudomonas aeruginosa. Extracts from other four plants exhibited a variable antimicrobial activity against all microorganisms, except Pseudomonas aeruginosa. Significant antioxidant activity was detected in all plant extracts. However, extracts from Pisidium guajava leaves contained significantly higher antioxidant activity compared to the other extracts tested. The antimicrobial and scavenging activities detected in this in vitro study in extracts from the five Palestinian medicinal plants suggest that further study is needed to identify active compounds to target diseases caused by a wide-spectrum pathogens.

Bacteriocin from Bacillus subtilis as a novel drug against diabetic foot ulcer bacterial pathogens

PubMed Central

Joseph, Baby; Dhas, Berlina; Hena, Vimalin; Raj, Justin

2013-01-01

Objective To isolate and identify Bacillus subtilis (B. subtilis) from soil and to characterize and partially purify the bacteriocin. To evaluate the antimicrobial activity against four diabetic foot ulcer bacterial pathogens. Methods Genotypic identification was done based on Bergey's manual of systemic bacteriology. Antimicrobial susceptibility test was done by Kirby-Bauer disc diffusion method. Colonies were identified by colony morphology and biochemical characterization and also compared with MTCC 121 strain. Further identification was done by 16S rRNA sequencing. Inhibitory activities of partially purified bacteriocin on all the DFU isolates were done by agar well diffusion method. The strain was identified to produce bacteriocin by stab overlay assay. Bacteriocin was extracted by organic solvent extraction using chloroform, further purified by HPLC and physical, and chemical characterization was performed. Results The four isolates showed high level of resistance to amoxyclav and sensitivity to ciprofloxacin. HPLC purification revealed that the extracts are bacteriocin. The phylogenetic tree analysis results showed that the isolate was 99% related to B. subtilis BSF01. The results reveled activity to all the four isolates and high level of activity was seen in case of Klebsiella sp. Conclusions Partially purified bacteriocin was found to have antimicrobial activity against the four diabetic foot ulcer bacterial pathogens, which can thus be applied as a better drug molecule on further studies. The strain B. subtilis are found to be safe for use and these antimicrobial peptides can be used as an antimicrobial in humans to treat DFU bacterial pathogens. PMID:24093784

Screening of selected single and polyherbal Ayurvedic medicines for Antibacterial and Antifungal activity

PubMed Central

Kekuda, T.R Prashith; Kavya, R; Shrungashree, R.M; Suchitra, S.V

2010-01-01

The present study deals with antimicrobial activity of ayurvedic drugs containing single herb (Amalaki Choorna and Yastimadhu Choorna) and combination of herbs (DN-90 and Asanadi Kwatha Choorna). Disc diffusion method was used to assess antibacterial activity and antifungal activity was tested using Poison food technique. Absence of bacterial growth around the discs impregnated with the aqueous extracts of drugs and reduction of fungal growth in poisoned plates indicated antimicrobial activity. Further, the results of antibacterial activity of Amalaki choorna were comparable with standard drug Streptomycin. Asanadi Kwatha Choorna inhibited bacteria to more extent than Yastimadhu choorna and DN-90. Among fungi tested, more antifungal activity was observed against Mucor sp. The antimicrobial activity of drugs tested could be due to active principles present in them. PMID:22557355

Development of an antimicrobial stewardship-based infectious diseases elective that incorporates human patient simulation technology.

PubMed

Falcione, Bonnie A; Meyer, Susan M

2014-10-15

To design an elective for pharmacy students that facilitates antimicrobial stewardship awareness, knowledge, and skill development by solving clinical cases, using human patient simulation technology. The elective was designed for PharmD students to describe principles and functions of stewardship programs, select, evaluate, refine, or redesign patient-specific plans for infectious diseases in the context of antimicrobial stewardship, and propose criteria and stewardship management strategies for an antimicrobial class at a health care institution. Teaching methods included active learning and lectures. Cases of bacterial endocarditis and cryptococcal meningitis were developed that incorporated human patient simulation technology. Forty-five pharmacy students completed an antimicrobial stewardship elective between 2010 and 2013. Outcomes were assessed using student perceptions of and performance on rubric-graded assignments. A PharmD elective using active learning, including novel cases conducted with human patient simulation technology, enabled outcomes consistent with those desired of pharmacists assisting in antimicrobial stewardship programs.

Antimicrobial activity of traditional medicinal plants from Ankober District, North Shewa Zone, Amhara Region, Ethiopia.

PubMed

Lulekal, E; Rondevaldova, J; Bernaskova, E; Cepkova, J; Asfaw, Z; Kelbessa, E; Kokoska, L; Van Damme, P

2014-05-01

Traditional medicinal plants have long been used in Ethiopia to treat human and livestock ailments. Despite a well-documented rich tradition of medicinal plant use in the country, their direct antimicrobial effects are still poorly known. To investigate the antimicrobial activity of 19 medicinal plant species that were selected based on the ethnobotanical information on their traditional use to treat infectious diseases in Ankober District. About 23 different ethanol extracts of plants obtained by maceration of various parts of 19 medicinal plant species were studied for potential antimicrobial activity using a broth microdilution method against Bacillus cereus, Bacteroides fragilis, Candida albicans, Clostridium perfringens, Enterococcus faecalis, Escherichia coli, Listeria monocytogenes, Pseudomonas aeruginosa, Salmonella enteritidis, Staphylococcus aureus, Staphylococcus epidermidis, and Streptococcus pyogenes. Plant extracts from Embelia schimperi Vatke (Myrsinaceae) showed the strongest antibacterial activity with a minimum inhibitory concentration (MIC) value of 64 µg/ml against B. cereus, L. monocytogenes, and S. pyogenes. Growth inhibitory activities were also observed for extracts of Ocimum lamiifolium Hochst. (Lamiaceae) against S. pyogenes, and those of Rubus steudneri Schweinf. (Rosaceae) against S. epidermidis at an MIC value of 128 µg/ml. Generally, 74% of ethanol extracts (17 extracts) showed antimicrobial activity against one or more of the microbial strains tested at an MIC value of 512 µg/ml or below. Results confirm the antimicrobial role of traditional medicinal plants of Ankober and warrant further investigations on promising medicinal plant species so as to isolate and characterise chemicals responsible for the observed strong antimicrobial activities.

Antimicrobial activity of four essential oils against pigmenting Pseudomonas fluorescens and biofilmproducing Staphylococcus aureus of dairy origin

PubMed Central

Pedonese, Francesca; Fratini, Filippo; Pistelli, Luisa; Porta, Federica Maria; Ciccio, Pierluigi Di; Fischetti, Roberto; Turchi, Barbara; Nuvoloni, Roberta

2017-01-01

Essential oils (EOs) are mixtures of secondary metabolites of plant origin with many useful properties, among which the antimicrobial activity is also of interest for the food industry. EOs can exert their antimicrobial potential both directly, in food products and active packaging, and indirectly, as sanitizing and anti-biofilm agents of food facility surfaces. Aim of this research was to evaluate the antimicrobial activity of four EOs (bergamot, cinnamon, manuka and thyme) against Pseudomonas fluorescens and Staphylococcus aureus isolated from milk and dairy products. The chemical composition of EOs was evaluated by Gas Chromatography-Mass Spectrometry analysis. Minimum Inhibitory Concentration values were determined by a microplate method against 9 Ps. fluorescens from marketed mozzarella with blue discoloration defect, and 3 biofilm-producing S. aureus from milk. Reference ATCC strains were included. Pigment production activity by Ps. fluorescens was assessed both in culture and in cheese. EOs of manuka (leptospermone 23%) and thyme (carvacrol 30%, pcymene 20%, thymol 15%) showed the highest antimicrobial activity against S. aureus, MIC values were 0.012%-0.024% and 0.024% v/v, respectively; meanwhile EOs from thyme and cinnamon (cinnamaldehyde 55%) exhibited the best activity against Ps. fluorescens with MIC values of 0.098%-0.195% and 0.195%-0.391% v/v, respectively. The antimicrobial activity of these EOs is promising and they could be exploited in the dairy production chain. PMID:29564238

Essential oil of the leaves of Ricinus communis L.: in vitro cytotoxicity and antimicrobial properties.

PubMed

Zarai, Zied; Ben Chobba, Ines; Ben Mansour, Riadh; Békir, Ahmed; Gharsallah, Néji; Kadri, Adel

2012-08-13

The aim of the present study was to appraise the antimicrobial activity of Ricinus communis L. essential oil against different pathogenic microorganisms and the cytotoxic activity against HeLa cell lines. The agar disk diffusion method was used to study the antibacterial activity of Ricinus communis L. essential oil against 12 bacterial and 4 fungi strains. The disc diameters of zone of inhibition (DD), the minimum inhibitory concentrations (MIC) and the concentration inhibiting 50% (IC50) were investigated to characterize the antimicrobial activities of this essential oil. The in vitro cytotoxicity of Ricinus communis L. essential oil was examined using a modified MTT assay; the viability and the IC50 were used to evaluate this test. The essential oil from the leaves of Ricinus communis L. was analyzed by GC-MS and bioassays were carried out. Five constituents of the oil were identified by GC-MS. The antimicrobial activity of the oil was investigated in order to evaluate its efficacy against twelve bacteria and four fungi species, using disc diffusion and minimum inhibitory concentration methods. The essential oil showed strong antimicrobial activity against all microorganisms tested with higher sensitivity for Bacillus subtilis, Staphylococcus aureus and Enterobacter cloacae. The cytotoxic and apoptotic effects of the essential oil on HeLa cell lines were examined by MTT assay. The cytotoxicity of the oil was quite strong with IC50 values less than 2.63 mg/ml for both cell lines. The present study showed the potential antimicrobial and anticarcinogenic properties of the essential oil of Ricinus communis L., indicating the possibilities of its potential use in the formula of natural remedies for the topical treatment of infections.

Do Aloe vera and Ageratum conyzoides enhance the anti-microbial activity of traditional medicinal soft soaps (Osedudu)?

PubMed

Moody, J O; Adebiyi, O A; Adeniyi, B A

2004-05-01

The Nigerian traditional soft soaps prepared using varied locally sourced raw materials such as cocoa pod ash (Theobroma cacao) palm kernel shaft ash (Elaies guineensis) have been evaluated for their physico-chemical properties and anti-microbial activities using standard pharmacopoeia protocols and an in-vitro agar diffusion bioassay method. The anti-microbial evaluation was done with and without incorporation of Aloe vera and Ageratum conyzoides extractives into the soap samples. Results showed that the physico-chemical properties of the soaps are dependent on the raw materials utilised. The incorporated medicinal plants used in this study, however, did not show any significant effect on the anti-microbial activities exhibited by the various soaps against the bacterial and fungal test organisms. Copyright 2004 Elsevier Ireland Ltd.

A Nanolayer Copper Coating for Prevention of Nosocomial Multi-Drug Resistant Infections

DTIC Science & Technology

2017-12-01

This can be done using a standard antimicrobial assay defined in ASTM method E2149-01 for determining antibacterial activity of immobilized... activity of a given substance are done in physiological buffer (with the exception of many antibiotics as these require active metabolism for efficacy...excellent antimicrobial activity against the three wound pathogens tested. In general, the trends in efficacy as a function of Cu loading and time make

Phytochemical characterization, antimicrobial activity and reducing potential of seed oil, latex, machine oil and presscake of Jatropha curcas.

PubMed

Sharma, Amit Kumar; Gangwar, Mayank; Kumar, Dharmendra; Nath, Gopal; Kumar Sinha, Akhoury Sudhir; Tripathi, Yamini Bhushan

2016-01-01

This study aims to evaluate the antimicrobial activity, phytochemical studies and thin layer chromatography analysis of machine oil, hexane extract of seed oil and methanol extract of presscake & latex of Jatropha curcas Linn (family Euphorbiaceae). J. curcas extracts were subjected to preliminary qualitative phytochemical screening to detect the major phytochemicals followed by its reducing power and content of phenol and flavonoids in different fractions. Thin layer chromatography was also performed using different solvent systems for the analysis of a number of constituents in the plant extracts. Antimicrobial activity was evaluated by the disc diffusion method, while the minimum inhibitory concentration, minimum bactericidal concentration and minimum fungicidal concentration were calculated by micro dilution method. The methanolic fraction of latex and cake exhibited marked antifungal and antibacterial activities against Gram-positive and Gram-negative bacteria. Phytochemical analysis revealed the presence of alkaloids, saponins, tannins, terpenoids, steroids, glycosides, phenols and flavonoids. Reducing power showed dose dependent increase in concentration compared to standard Quercetin. Furthermore, this study recommended the isolation and separation of bioactive compounds responsible for the antibacterial activity which would be done by using different chromatographic methods such as high-performance liquid chromatography (HPLC), GC-MS etc. The results of the above study suggest that all parts of the plants possess potent antibacterial activity. Hence, it is important to isolate the active principles for further testing of antimicrobial and other biological efficacy.

Antimicrobial Lemongrass Essential Oil-Copper Ferrite Cellulose Acetate Nanocapsules.

PubMed

Liakos, Ioannis L; Abdellatif, Mohamed H; Innocenti, Claudia; Scarpellini, Alice; Carzino, Riccardo; Brunetti, Virgilio; Marras, Sergio; Brescia, Rosaria; Drago, Filippo; Pompa, Pier Paolo

2016-04-20

Cellulose acetate (CA) nanoparticles were combined with two antimicrobial agents, namely lemongrass (LG) essential oil and Cu-ferrite nanoparticles. The preparation method of CA nanocapsules (NCs), with the two antimicrobial agents, was based on the nanoprecipitation method using the solvent/anti-solvent technique. Several physical and chemical analyses were performed to characterize the resulting NCs and to study their formation mechanism. The size of the combined antimicrobial NCs was found to be ca. 220 nm. The presence of Cu-ferrites enhanced the attachment of LG essential oil into the CA matrix. The magnetic properties of the combined construct were weak, due to the shielding of Cu-ferrites from the polymeric matrix, making them available for drug delivery applications where spontaneous magnetization effects should be avoided. The antimicrobial properties of the NCs were significantly enhanced with respect to CA/LG only. This work opens novel routes for the development of organic/inorganic nanoparticles with exceptional antimicrobial activities.

Comparative evaluation of the antimicrobial efficacy of four chewing sticks commonly used in South India: an in vitro study.

PubMed

Elangovan, Arun; Muranga, Jayanthi; Joseph, Elizabeth

2012-01-01

The use of chewing sticks has been well documented since ancient times in India. Chewing sticks are a good alternative to the toothbrush for maintaining oral hygiene. The present study was designed and conducted to compare and evaluate the antimicrobial effects of the aqueous extracts of neem, miswak, mango, and banyan chewing sticks against two bacterial species considered the most important in the initiation and progression of dental caries, namely Streptococcus mutans and Lactobacillus acidophilus, respectively. Twigs of the above mentioned chewing sticks were sun dried and powdered, and sterile aqueous solutions of 10%, 25% and 50% concentrations were prepared. Culture plates for S mutans and L acidophilus were prepared and the growth was transferred to nutrient agar and Mueller-Hinton agar; antimicrobial activity of the extracts was tested after 72 h, using the disc diffusion method. Normal saline was used as control. The antimicrobial activity of neem, miswak, and mango extracts increased as their concentrations increased. Both banyan extract and saline showed no antimicrobial activity against the organisms tested. Based on the zones of inhibition, aqueous extracts of neem showed the most antimicrobial activity against S mutans, while miswak extracts showed superior antimicrobial activity against L acidophilus. We recommend further phytochemical and pharmacological studies to discover newer nonsynthetic tooth pastes and mouthwashes.

Antimicrobial activity of Ulopterol isolated from Toddalia asiatica (L.) Lam.: a traditional medicinal plant.

PubMed

Karunai Raj, M; Balachandran, C; Duraipandiyan, V; Agastian, P; Ignacimuthu, S

2012-03-06

The leaves of Toddalia asiatica (L.) Lam. (Rutaceae) are widely used in folk medicine in India to treat various ailments like cough, malaria, indigestion, influenza lung diseases and rheumatism, fever, stomach ailments, cholera and diarrhea. In our earlier communication we have reported the antimicrobial study on the various extracts of the leaves and the isolation and identification of Flindersine, a quinolone alkaloid as the major active principle. In the present study, we report the antibacterial and antifungal activities of Ulopterol, a coumarin isolated as another major active antimicrobial principle. The leaves were successively extracted with hexane, chloroform, ethyl acetate, methanol and water. The extracts were studied for their antimicrobial activity against selected bacteria and fungi by using disc-diffusion method. The ethyl acetate extract which was found to possess highest antimicrobial activity was subjected to activity guided fractionation by column chromatography over silica gel. This resulted in the isolation of the coumarin, Ulopetrol, an active principle besides Flindersine which was reported by us earlier. The structure of the compound was elucidated using physical and spectroscopic data. Flindersine and Ulopterol were quantified by HPLC. Ulopterol showed activity against the bacteria viz. Staphylococcus epidermidis, Enterobacter aerogenes, Shigella flexneri, Klebsiella pneumoniae (ESBL-3967), Escherichia coli (ESBL-3984) and fungi viz. Aspergillus flavus, Candida krusei and Botrytis cinerea. Quantification by HPLC showed the content of Flindersine and Ulopterol to be 0.361% and 0.266% respectively on dry weight basis of the leaves. Ethyl acetate extract (successive extraction) contained Ulopterol, a coumarin, besides Flindersine, a quinolone alkaloid, as a major active principle in the antimicrobial studies. This is the first report of the antimicrobial activity of Ulopterol and also its first report from the plant. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Activity of Topical Antimicrobial Agents Against Multidrug-Resistant Bacteria Recovered from Burn Patients

DTIC Science & Technology

2010-01-01

produced by Pseudomonas fluorescens [19] Inhibition of RNA and protein synthesis by targeting the isoleucine-binding site on the isoleucyl-transfer-RNA...multidrug-resistant (MDR) bacteria. We compared two methods of determining topical antimicrobial susceptibilities. Methods: Isolates of Pseudomonas ...aeruginosa, methicillin-resistant Staphylococcus aureus (MRSA), extended spectrum beta-lactamase (ESBL) producing Klebsiella pneumoniae, and

Determination of the antibiofilm, antiadhesive, and anti-MRSA activities of seven Salvia species

PubMed Central

Al-Bakri, Amal G.; Othman, Ghadeer; Afifi, Fatma U.

2010-01-01

Background: Several Salvia species are indigenous to Jordan and are widely used as beverages and spices and for their medicinal properties. The objective of the study was to establish the antimicrobial activities, including the antiadhesive and antibiofilm effects of seven different Salvia species. Materials and Methods: Methods used for planktonic culture included agar diffusion, broth microdilution, and minimal biocidal concentration determination while viable count was used for the determination of the antibiofilm and antiadhesion activities. Overnight cultures of reference strains of Candida albicans, Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus and clinical strains of methicillin-resistant S. aureus (MRSA) were used as test microorganisms. Results: An antimicrobial activity toward planktonic cultures demonstrated a significant bacteriocidal activity (≥4 log cycle reduction) for the S. triloba extract against S. aureus including MRSA. Its volatile oil exhibited an antimicrobial activity covering all tested microorganisms with the exception of P. aeruginosa. S. triloba extract and volatile oil were successful in preventing and controlling the biofilm, demonstrating antiadhesion and antibiofilm activities, respectively. Conclusion: These reported activities for S. triloba extract and volatile oil allows their listing as potential antibiofilm and anti-MRSA natural agents. This might suggest their use as an antiseptic in the prophylaxis and treatment of S. aureus-associated skin infections. The antimicrobial activity of the other tested Salvia species was negligible. PMID:21120026

Antimicrobial activity of fractions and subfractions of Elaeagia utilis against microorganisms of importance in dental caries.

PubMed

Aldana, Jennyfer; Téllez, Nohemí; Gamboa, Fredy

2013-01-01

Dental caries is a multifactorial infectious disease that leads to the destruction of dental hard tissue. The main goal of research into medicinal plants is to seek compounds with antimicrobial activity for subsequent use in prevention strategies and control of infectious diseases. The aim of this study was to evaluate the antimicrobial activity of fractions and subfractions obtained from Elaeagia utilis against Streptococcus mutans, Streptococcus sobrinus and Lactobacillus acidophilus. The plant material was collected in the town of Alban (Cundinamarca, Colombia), which is located at an altitude of 2245 meters above sea level. Two extracts were obtained by cold maceration of E. utilis leaves in (a) petroleum ether extract and (b) ethanol extract. Fractions were obtained from the petroleum ether extract by column vacuum chromatography, and from the ethanol extract by continuous liquid/liquid partitioning. The antimicrobial activity of fractions and subfractions was evaluated by the well diffusion method. At a concentration of 10 mg/well, several fractions from both extracts showed antimicrobial activity against S. mutans, S. sobrinus and L. acidophilus. Among the ethanol extract fractions, the dichloromethane fraction had notably greater antimicrobial activity. It was sub-partitioned, yielding three subfractions with inhibitory activity, of which the most active was MeOH: H2O (Bp) with minimum inhibitory concentration 0.1 mg/well on the 3 study bacteria. Terpenes, sesquiterpenlactones and simple phenolic compounds were identified in it. In conclusion, this study shows the antimicrobial potential of fractions and subfractions obtained from extracts of E. utilis leaves against bacteria that are important in dental caries.

Supercritical carbon dioxide extraction of compounds with antimicrobial activity from Origanum vulgare L.: determination of optimal extraction parameters.

PubMed

Santoyo, S; Cavero, S; Jaime, L; Ibañez, E; Señoráns, F J; Reglero, G

2006-02-01

Oregano leaves were extracted using a pilot-scale supercritical fluid extraction plant under a wide range of extraction conditions, with the goal of determining the extraction and fractionation conditions to obtain extracts with optimal antimicrobial activity. In this investigation, the essential oil-rich fractions were selectively precipitated in the second separator, and their chemical composition and antimicrobial activity were investigated. Gas chromatography-mass spectrometry analysis of the various fractions resulted in the identification of 27 compounds of the essential oil. The main components of these fractions were carvacrol, trans-sabinene hydrate, cis-piperitol, borneol, terpinen-4-ol, and linalool. Antimicrobial activity was investigated by the disk diffusion and broth dilution methods against six different microbial species, including two gram-positive bacteria (Staphylococcus aureus and Bacillus subtilis), two gram-negative bacteria (Escherichia coli and Pseudomonas aeruginosa), a yeast (Candida albicans), and a fungus (Aspergillus niger). All of the supercritical fluid extraction fractions obtained showed antimicrobial activity against all of the microorganisms tested, although the most active fraction was the one obtained in experiment 5 (fraction was obtained with 7% ethanol at 150 bar and 40 degrees C). C. albicans was the most sensitive microorganism to the oregano extracts, whereas the least susceptible was A. niger. Carvacrol, sabinene hydrate, borneol, and linalool standards also showed antimicrobial activity against all of the microorganisms tested, with carvacrol being the most effective. Consequently, it was confirmed that essential oil from experiment 5, with the best antimicrobial activity, also presented the highest quantity of carvacrol.

Antimicrobial Effect of Jasminum grandiflorum L. and Hibiscus rosa-sinensis L. Extracts Against Pathogenic Oral Microorganisms--An In Vitro Comparative Study.

PubMed

Nagarajappa, Ramesh; Batra, Mehak; Sharda, Archana J; Asawa, Kailash; Sanadhya, Sudhanshu; Daryani, Hemasha; Ramesh, Gayathri

2015-01-01

To assess and compare the antimicrobial potential and determine the minimum inhibitory concentration (MIC) of Jasminum grandiflorum and Hibiscus rosa-sinensis extracts as potential anti-pathogenic agents in dental caries. Aqueous and ethanol (cold and hot) extracts prepared from leaves of Jasminum grandiflorum and Hibiscus rosa-sinensis were screened for in vitro antimicrobial activity against Streptococcus mutans and Lactobacillus acidophilus using the agar well diffusion method. The lowest concentration of every extract considered as the minimum inhibitory concentration (MIC) was determined for both test organisms. Statistical analysis was performed with one-way analysis of variance (ANOVA). At lower concentrations, hot ethanol Jasminum grandiflorum (10 μg/ml) and Hibiscus rosa-sinensis (25 μg/ml) extracts were found to have statistically significant (P≤0.05) antimicrobial activity against S. mutans and L. acidophilus with MIC values of 6.25 μg/ml and 25 μg/ml, respectively. A proportional increase in their antimicrobial activity (zone of inhibition) was observed. Both extracts were found to be antimicrobially active and contain compounds with therapeutic potential. Nevertheless, clinical trials on the effect of these plants are essential before advocating large-scale therapy.

Antimicrobial, antioxidant and cytotoxic properties of essential oil from Dictamnus angustifolius.

PubMed

Sun, Jianbo; Wang, Xinzhi; Wang, Pei; Li, Linzhen; Qu, Wei; Liang, Jingyu

2015-01-15

Dictamnus angustifolius (Rutaceae) has been used as an alternative for folk medicine, Dictamnus dasycarpus in the treatment of rheumatism, bleeding, itching, jaundice, chronic hepatitis, and skin diseases in Xinjiang Province of China. The aim of this study was to evaluate the antimicrobial and antioxidant activities of essential oil (EO) from Dictamnus angustifolius, correlated with their chemical composition and evaluate their cytotoxicity. The EO were extracted by water-distillation using a Clevenger-type apparatus. The chemical composition of EO was identified by GC-MS analysis. The antimicrobial activity was evaluated against five microorganisms by the agar disc diffusion method and minimal inhibitory concentration (MIC) assay. The antioxidant activity was measured by employing DPPH and FRAP assays. The cytotoxic activity was evaluated in the mammalian cells lines A549, MCF7, B16 and LoVo using the MTT method to assess cell viability. 52 compounds representing the 97.2% of the total oil were identified by GC/MS. The major constituents of the oil were tetramethylenecyclobutane (42.07%) and fraxinellone (19.06%). The antimicrobial activity showed that the EO possess significant inhibition in Monilia albican ATCC 10231 and Staphylococcus aureus ATCC 6538. The antioxidant activity suggested that the EO possess significant reducing power. The cytotoxic activity of the EO in MCF7 and LoVo cells was significant stronger than in the other cell lines. This study is the first characterization of the chemical composition and biological activities of EO from Dictamnus angustifolius. All experimental data indicate that the EO have not only remarkable antioxidant properties but also potential antimicrobial activity and cytotoxic activities. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Antimicrobial activity of human pancreatic juice and its interaction with antibiotics.

PubMed Central

Minelli, E B; Benini, A; Bassi, C; Abbas, H; Falconi, M; Locatelli, F; de Marco, R; Pederzoli, P

1996-01-01

Pancreatic juice (PJ) should be a factor of variability in the antimicrobial activity of antibiotics eliminated by the pancreas during pancreatic infections. We studied its effects on the activity of antimicrobial drugs with different mechanisms of action. Samples of pure PJ were collected from 16 patients with stabilized external pancreatic fistulas. The antimicrobial activity of the juice at different concentrations (from 1.25 to 100%) alone and in combination with mezlocillin, imipenem, ceftriaxone, gentamicin, ofloxacin, and ciprofloxacin was studied by a microbiological method (continuous turbidimetric recording of bacterial growth). The human PJ showed dose-dependent antimicrobial activity that increased directly with the concentration. The activity of the antibiotics at bactericidal concentrations were not modified by the PJ, while the combination with subinhibitory concentrations produced the following variable and different effects: (i) additivity with mezlocillin, ceftriaxone, gentamicin, and ciprofloxacin and autonomy (no interaction) with imipenem and ofloxacin against Providencia rettgeri and (ii) additivity with ceftriaxone, ofloxacin, gentamicin, imipenem, and mezlocillin and autonomy with ciprofloxacin against Escherichia coli. In the presence of PJ, fluoroquinolones showed constant positive effects, while beta-lactams showed more variable antimicrobial activity. Antibiotic concentrations and PJ pharmacodynamics are the main factors determining the final effect of the interaction in vitro. These results may be useful in choosing antibiotics for the treatment of pancreatic infections when they are supplemented with the pharmacokinetic data for each drug. PMID:8878588

A Nanolayer Copper Coating for Prevention Nosocomial Multi-Drug Resistant Infections

DTIC Science & Technology

2016-10-01

done using a standard antimicrobial assay defined in ASTM method E2149-01 for determining antibacterial activity of immobilized agents under...are optimized for bacterial growth and do not represent typical conditions. Therefore, most studies reporting on the antimicrobial activity of a...given substance are done in physiological buffer (with the exception of many antibiotics as these require active metabolism for efficacy). This can be

In Vitro Antimicrobial Potential of the Lichen Parmotrema sp. Extracts against Various Pathogens.

PubMed

Chauhan, Ritika; Abraham, Jayanthi

2013-07-01

The ongoing increasing antibiotic resistance is one of the biggest challenges faced by global public health. The perennial need for new antimicrobials against a background of increasing antibiotic resistance in pathogenic and opportunistic microorganisms obliges the scientific community to constantly develop new drugs and antimicrobial agents. Lichens are known prolific sources of natural antimicrobial drugs and biologically active natural products. This study was aimed to explore in vitro antimicrobial activity of lichen Parmotrema sp. The methanol and aqueous extracts of lichen Parmotrema sp. was extracted using Soxhlet extractor. Antibiotic assessment of methanol and aqueous extracts was done against eight bacterial (Escherichia coli, Staphylococcus aureus, Proteus mirabilis, Salmonella sp., Shigella sp., Enterococci faecalis, Pseudomonas aeruginosa, Klebsiella pneumoniae,) clinical pathogens and five plant pathogenic fungal strains (Aspergillus terreus strain JAS1, Scedosporium sp. JAS1, Ganoderma sp. JAS4, Candida tropicalis and Fusarium sp.) by Kirby-Bauer method. The methanol lichen Parmotrema sp. extract inhibited all the test organisms. The highest antibacterial activity was found against Pseudomonas aeruginosa and Staphylococcus aureus. The weakest activity was manifested in Salmonella sp. and Scedosporium sp. JAS1. Strong antifungal effect was found against Ganoderma sp. JAS4 and Fusarium sp. The aqueous lichen Parmotrema sp. extract revealed neither antibacterial nor antifungal activity. The present study shows that tested lichen Parmotrema sp. extracts demonstrated a strong antimicrobial effect. That suggests the active components from methanol extracts of the investigated lichen Parmotrema sp. can be used as natural antimicrobial agent against pathogens.

Synthesis and Antimicrobial Activity of Silver-Doped Hydroxyapatite Nanoparticles

PubMed Central

Ciobanu, Carmen Steluta; Iconaru, Simona Liliana; Chifiriuc, Mariana Carmen; Costescu, Adrian; Le Coustumer, Philippe; Predoi, Daniela

2013-01-01

The synthesis of nanosized particles of Ag-doped hydroxyapatite with antibacterial properties is of great interest for the development of new biomedical applications. The aim of this study was the evaluation of Ca10−xAgx(PO4)6(OH)2 nanoparticles (Ag:HAp-NPs) for their antibacterial and antifungal activity. Resistance to antimicrobial agents by pathogenic bacteria has emerged in the recent years and became a major health problem. Here, we report a method for synthesizing Ag doped nanocrystalline hydroxyapatite. A silver-doped nanocrystalline hydroxyapatite was synthesized at 100°C in deionised water. Also, in this paper Ag:HAp-NPs are evaluated for their antimicrobial activity against Gram-positive and Gram-negative bacteria and fungal strains. The specific antimicrobial activity revealed by the qualitative assay is demonstrating that our compounds are interacting differently with the microbial targets, probably due to the differences in the microbial wall structures. PMID:23509801

Synthesis and antimicrobial activity of silver-doped hydroxyapatite nanoparticles.

PubMed

Ciobanu, Carmen Steluta; Iconaru, Simona Liliana; Chifiriuc, Mariana Carmen; Costescu, Adrian; Le Coustumer, Philippe; Predoi, Daniela

2013-01-01

The synthesis of nanosized particles of Ag-doped hydroxyapatite with antibacterial properties is of great interest for the development of new biomedical applications. The aim of this study was the evaluation of Ca(10-x)Ag(x)(PO4)6(OH)2 nanoparticles (Ag:HAp-NPs) for their antibacterial and antifungal activity. Resistance to antimicrobial agents by pathogenic bacteria has emerged in the recent years and became a major health problem. Here, we report a method for synthesizing Ag doped nanocrystalline hydroxyapatite. A silver-doped nanocrystalline hydroxyapatite was synthesized at 100°C in deionised water. Also, in this paper Ag:HAp-NPs are evaluated for their antimicrobial activity against gram-positive and gram-negative bacteria and fungal strains. The specific antimicrobial activity revealed by the qualitative assay is demonstrating that our compounds are interacting differently with the microbial targets, probably due to the differences in the microbial wall structures.

Antimicrobial and antimalarial properties of medicinal plants used by the indigenous tribes of Andaman and Nicobar Islands, India.

PubMed

Chander, M Punnam; Pillai, C R; Sunish, I P; Vijayachari, P

2016-07-01

In this study, methanol extracts of six medicinal plants (Alstonia macrophylla, Claoxylon indicum, Dillenia andamanica, Jasminum syringifolium, Miliusia andamanica and Pedilanthus tithymaloides) traditionally used by Nicobarese tribes of Andaman and Nicobar Islands were studied for antimicrobial and antimalarial activities as well as preliminary photochemical analysis. Plants were collected from Car Nicobar of Andaman and Nicobar Islands and the ethnobotanical data were gathered from traditional healers who inhabit the study area. The methanol extracts were obtained by cold percolation method and the antimicrobial activity was found using agar well diffusion method. Among the plants tested, J. syringifolium, D. andamanica, C. indicum were most active. The antimalarial activity was evaluated against Plasmodium falciparum chloroquine-sensitive MRC-2 isolate. The crude extract of M. andamanica showed excellent antimalarial activity followed by extracts of P. tithymaloides, J. syringifolium and D. andamanica. The chemical injury to erythrocytes was also carried out and it showed that, there were no morphological changes in erythrocytes by the methanol crude extracts. The in vitro antimicrobial and antimalarial activity might be due to the presence of alkaloids, flavonoids, triterpenes, sterols, tannins and saponins in the methanol extracts of tested plants. Copyright © 2016 Elsevier Ltd. All rights reserved.

Ultrathin hexagonal MgO nanoflakes coated medical textiles and their enhanced antibacterial activity

NASA Astrophysics Data System (ADS)

Veeran Ponnuvelu, Dinesh; Selvaraj, Aravind; Prema Suriyaraj, Shanmugam; Selvakumar, Rajendran; Pulithadathail, Biji

2016-10-01

A facile hydrothermal method for development of ultrathin MgO nanoplates from different precursors and their enhanced antibacterial activity after coating onto medical textiles is reported. Ultrathin MgO nanoplates having hexagonal structure were characterized using UV-visible spectroscopy, atomic force microscopy, field emission scanning electron microscopy, x-ray diffraction and high resolution transmission electron microscopy. The formation of MgO nanoplates was found to exhibit profound anionic effect leading to ultrathin, planar structures with exposed MgO [111] facets, which may be responsible for enhanced antimicrobial activity. Medical fabrics (bleached 100% cotton) were coated with MgO nanoplates using pad-dry-cure method. The antibacterial activity of these fabrics was tested against Bacillus subtilis and Escherichia coli. The MgO nanoplates coated onto the fabric were found to have good adherence properties owing to their two-dimensional structure and were durable even after repeated washings without substantial reduction in the antimicrobial activity. The enhanced antibacterial activity may be attributed to the presence of oxygen vacancies, surface oxygen anions and hydroxyl groups on the surface of MgO nanoplates. This cost-effective functional finish (anti-microbial) to cotton fabric using MgO nanoplates may be suitable for many prospective medical applications and can serve as an alternative to the costlier silver based antimicrobial textiles.

Dimers of coumarin-1,2,3-triazole hybrids bearing alkyl spacer: Design, microwave-assisted synthesis, molecular docking and evaluation as antimycobacterial and antimicrobial agents

NASA Astrophysics Data System (ADS)

Ashok, Dongamanti; Gundu, Srinivas; Aamate, Vikas Kumar; Devulapally, Mohan Gandhi; Bathini, Raju; Manga, Vijjulatha

2018-04-01

The present study demonstrated the synthesis of new series of coumarin-1,2,3-triazole hybrids under microwave irradiation method. Several dimers of coumarin based 1,2,3-triazole derivatives were synthesized and their antimycobacterial and antimicrobial activities were investigated. The antimycobacterial activity screening results revealed that compounds 6i and 6j were the most active against Mycobacterium tuberculosis H37Rv strain. The active compounds were further evaluated for cytotoxicity with HEK cell lines and exhibited less % of inhibition. The same synthetic hybrids were evaluated for their antimicrobial activity against various bacterial strains and fungal strains and compounds 6e, 6h, 6i and 6j were found to be the most promising antimicrobial potent molecules. Furthermore, the active compounds against Mycobacterium tuberculosis were evaluated for their molecular docking studies against pantothenate synthetase (PS) enzyme of MTB and the docking results are in well agreement with the antitubercular evaluation results.

Evaluating the antimicrobial activity of Nisin, Lysozyme and Ethylenediaminetetraacetate incorporated in starch based active food packaging film.

PubMed

Bhatia, Sugandha; Bharti, Anoop

2015-06-01

The pleothera of micro organisms obtained from contaminated food cultured in a starch broth was effectively tested against antibacterial agents, i.e. nisin, lysozyme and chelating agent EDTA. A variety of combination treatments of these antimicrobial agents and their incorporation in Starch based active packaging film according to their permissibility standards was done. 4 variables of Nisin concentration (ranging from 0 to 750 IU/ml), 3 variables of lysozyme concentration (ranging from 0 to 500 IU/ml) and 3 variables of EDTA concentration from (0 to 20 μM) were chosen. Bacterial inhibition by combination of different levels of different factors without antimicrobial films was evaluated using a liquid incubation method. The samples were assayed for turbidity at interval of 2, 4 and 24 h to check effectiveness of combined effects of antimicrobial agents which proved a transitory bactericidal effect for short incubation times. Zone of Inhibition was observed in the antimicrobial films prepared by agar diffusion method. Statistical analysis of experimental data for their antimicrobial spectrum was carried out by multi regression analysis and ANOVA using Design-Expert software to plot the final equation in terms of coded factors as antimicrobial agents. The experimental data indicated that the model was highly significant. Results were also evaluated graphically using response surface showing interactions between two factors, keeping other factor fixed at values at the center of domain. Synergy was also determined among antibacterial agents using the fractional inhibitory concentration (FIC) index which was observed to be 0.56 supporting the hypothesis that nisin and EDTA function as partial synergistically. The presented work aimed to screen in quick fashion the combinatorial effect of three antimicrobial agents and evaluating their efficacy in anti microbial film development.

Discovery of novel antimicrobial peptides: A transcriptomic study of the sea anemone Cnidopus japonicus.

PubMed

Grafskaia, Ekaterina N; Polina, Nadezhda F; Babenko, Vladislav V; Kharlampieva, Daria D; Bobrovsky, Pavel A; Manuvera, Valentin A; Farafonova, Tatyana E; Anikanov, Nikolay A; Lazarev, Vassili N

2018-04-01

As essential conservative component of the innate immune systems of living organisms, antimicrobial peptides (AMPs) could complement pharmaceuticals that increasingly fail to combat various pathogens exhibiting increased resistance to microbial antibiotics. Among the properties of AMPs that suggest their potential as therapeutic agents, diverse peptides in the venoms of various predators demonstrate antimicrobial activity and kill a wide range of microorganisms. To identify potent AMPs, the study reported here involved a transcriptomic profiling of the tentacle secretion of the sea anemone Cnidopus japonicus. An in silico search algorithm designed to discover toxin-like proteins containing AMPs was developed based on the evaluation of the properties and structural peculiarities of amino acid sequences. The algorithm revealed new proteins of the anemone containing antimicrobial candidate sequences, and 10 AMPs verified using high-throughput proteomics were synthesized. The antimicrobial activity of the candidate molecules was experimentally estimated against Gram-positive and -negative bacteria. Ultimately, three peptides exhibited antimicrobial activity against bacterial strains, which suggests that the method can be applied to reveal new AMPs in the venoms of other predators as well.

Study of sporadical properties of crosslinked polyelectrolyte multilayers

NASA Astrophysics Data System (ADS)

Balu, Deebika

Polyelectrolyte multilayers (PEM) have become a highly studied class of materials due to the range of their applicability in many areas of research, including biology, chemistry and materials science. Recent advances in surface coatings have enabled modification of PEM surfaces to provide desirable properties such as controlled release, super-hydrophobicity, biocompatibility, antifouling and antibacterial properties. In the past decade, antimicrobial PEM coatings have been investigated as a safer alternative to the traditional disinfection methods that usually involve application of hazardous chemicals onto the surface to be cleaned. These antimicrobial coatings could be applied to common surfaces prone to colonization of bacteria (such as bench tops, faucet handles, etc) to supplement routine sanitization protocols by providing sustained antimicrobial activity. Vegetative bacteria (such as Escherichia coli) are more susceptible to antimicrobial agents than bacterial species that form spores. Hence, the antimicrobial activity of PEM coatings fabricated using Layer by Layer (LbL) technique were assayed using Bacillus anthracis spores (Sterne strain). In this thesis, the sporicidal effect of various polyelectrolyte multilayer coatings containing cross-linked polymers immersed in bleach have been evaluated as potential augmentation to existing disinfection methods.

Anti-microbial Activity of Tulsi {Ocimum Sanctum (Linn.)} Extract on a Periodontal Pathogen in Human Dental Plaque: An Invitro Study

PubMed Central

Devaraj, C.G.; Agarwal, Payal

2016-01-01

Introduction Tulsi is a popular healing herb in Ayurvedic medicine. It is widely used in the treatment of several systemic diseases because of its anti-microbial property. However, studies documenting the effect of Tulsi on oral disease causing organisms are rare. Hence, an attempt was made to determine the effect of Tulsi on a periodontal microorganism in human dental plaque. Aim To determine if Ocimum sanctum (Linn.) has an anti-microbial activity (Minimum Inhibitory Concentration and zone of inhibition) against Actinobacillus actinomycetemcomitans in human dental plaque and to compare the antimicrobial activity of Ocimum sanctum(Linn.) extract with 0.2% chlorhexidine as the positive control and dimethyl sulfoxide as the negative control. Materials and Methods A lab based invitro experimental study design was adopted. Ethanolic extract of Ocimum sanctum (Linn.) was prepared by the cold extraction method. The extract was diluted with an inert solvent, dimethyl sulfoxide, to obtain ten different concentrations (1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%) of extract. Plaque sample was collected from 05 subjects diagnosed with periodontal disease. Isolation of Actinobacillus actinomycetemcomitans from plaque samples was done using Tryptic Soy Serum Bacitracin Vancomycin agar (TSBV) medium. Identification of Actinobacillus actinomycetemcomitans was done based on cultural, microscopic, biochemical characterization and multiple drug resistance patterns. Anti-microbial activity of Ocimum sanctum (Linn.) extract was tested by agar well-diffusion method against 0.2% chlorhexidine as a positive control and dimethyl sulfoxide as a negative control. The zone of inhibition was measured in millimeters using Vernier callipers. Results At the 6% w/v concentration of Ocimum sanctum (Linn.) extract, a zone of inhibition of 22 mm was obtained. This was the widest zone of inhibition observed among all the 10 different concentrations tested. The zone of inhibition for positive control was 25mm and no zone of inhibition was observed around the negative control. Conclusion Ocimum sanctum (Linn.) extract demonstrated an antimicrobial activity against Actinobacillus actinomycetemcomitans. The maximum antimicrobial potential was observed at the 6% concentration level. PMID:27135002

Hydrolates from lavender (Lavandula angustifolia)--their chemical composition as well as aromatic, antimicrobial and antioxidant properties.

PubMed

Prusinowska, Renata; Śmigielski, Krzysztof; Stobiecka, Agnieszka; Kunicka-Styczyńska, Alina

2016-01-01

It was shown that the method for obtaining hydrolates from lavender (Lavandula angustifolia) influences the content of active compounds and the aromatic, antimicrobial and antioxidant properties of the hydrolates. The content of volatile organic compounds ranged from 9.12 to 97.23 mg/100 mL of hydrolate. Lavender hydrolate variants showed low antimicrobial activity (from 0% to 0.05%). The radical scavenging activity of DPPH was from 3.6 ± 0.5% to 3.8 ± 0.6% and oxygen radical absorbance capacity (ORAC(FL)) results were from 0 to 266 μM Trolox equivalent, depending on the hydrolate variant.

Antimicrobial Testing Methods & Procedures: MB-26-02

EPA Pesticide Factsheets

Information about ATMP - SOP Neutralization of Microbicidal Activity using the OECD Quantitative Method for Evaluating Bactericidal Activity of Microbicides Used on Hard, Non-Porous Surfaces - MB-26-02

Antimicrobial activities of three species of family mimosaceae.

PubMed

Mahmood, Adeel; Mahmood, Aqeel; Qureshi, Rizwana Aleem

2012-01-01

The antimicrobial activities of crude methanolic extract of leaves of Acacia nilotica L., Albizia lebbeck L. and Mimosa himalayana Gamble belonging to family mimosaceae were investigated in this research work. Antibacterial activity was studied by agar well diffusion method against one gram-positive Bacillus subtilis and three gram-negative Pseudomonas aeruginosa, Escherichia coli and Klebsiella pneumonia. Crude extract of all plants showed best activity against gram-negative bacterial strains while minor inhibition zones were found against gram positive bacterial strains. Antifungal activity of crude plant extract was screened by agar tube dilution method against Aspergillus nigar and Aspergillus flavus. These results showed that these plants extracts have potential against bacterias, while against fungi their activity is not much effective.

In vitro antimicrobial activity of five essential oils on multidrug resistant Gram-negative clinical isolates.

PubMed

Sakkas, Hercules; Gousia, Panagiota; Economou, Vangelis; Sakkas, Vassilios; Petsios, Stefanos; Papadopoulou, Chrissanthy

2016-01-01

The emergence of drug-resistant pathogens has drawn attention on medicinal plants for potential antimicrobial properties. The objective of the present study was the investigation of the antimicrobial activity of five plant essential oils on multidrug resistant Gram-negative bacteria. Basil, chamomile blue, origanum, thyme, and tea tree oil were tested against clinical isolates of Acinetobacter baumannii (n = 6), Escherichia coli (n = 4), Klebsiella pneumoniae (n = 7), and Pseudomonas aeruginosa (n = 5) using the broth macrodilution method. The tested essential oils produced variable antibacterial effect, while Chamomile blue oil demonstrated no antibacterial activity. Origanum, Thyme, and Basil oils were ineffective on P. aeruginosa isolates. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration values ranged from 0.12% to 1.50% (v/v) for tea tree oil, 0.25-4% (v/v) for origanum and thyme oil, 0.50% to >4% for basil oil and >4% for chamomile blue oil. Compared to literature data on reference strains, the reported MIC values were different by 2SD, denoting less successful antimicrobial activity against multidrug resistant isolates. The antimicrobial activities of the essential oils are influenced by the strain origin (wild, reference, drug sensitive, or resistant) and it should be taken into consideration whenever investigating the plants' potential for developing new antimicrobials.

High-Throughput Intracellular Antimicrobial Susceptibility Testing of Legionella pneumophila.

PubMed

Chiaraviglio, Lucius; Kirby, James E

2015-12-01

Legionella pneumophila is a Gram-negative opportunistic human pathogen that causes a severe pneumonia known as Legionnaires' disease. Notably, in the human host, the organism is believed to replicate solely within an intracellular compartment, predominantly within pulmonary macrophages. Consequently, successful therapy is predicated on antimicrobials penetrating into this intracellular growth niche. However, standard antimicrobial susceptibility testing methods test solely for extracellular growth inhibition. Here, we make use of a high-throughput assay to characterize intracellular growth inhibition activity of known antimicrobials. For select antimicrobials, high-resolution dose-response analysis was then performed to characterize and compare activity levels in both macrophage infection and axenic growth assays. Results support the superiority of several classes of nonpolar antimicrobials in abrogating intracellular growth. Importantly, our assay results show excellent correlations with prior clinical observations of antimicrobial efficacy. Furthermore, we also show the applicability of high-throughput automation to two- and three-dimensional synergy testing. High-resolution isocontour isobolograms provide in vitro support for specific combination antimicrobial therapy. Taken together, findings suggest that high-throughput screening technology may be successfully applied to identify and characterize antimicrobials that target bacterial pathogens that make use of an intracellular growth niche. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

High-Throughput Intracellular Antimicrobial Susceptibility Testing of Legionella pneumophila

PubMed Central

Chiaraviglio, Lucius

2015-01-01

Legionella pneumophila is a Gram-negative opportunistic human pathogen that causes a severe pneumonia known as Legionnaires' disease. Notably, in the human host, the organism is believed to replicate solely within an intracellular compartment, predominantly within pulmonary macrophages. Consequently, successful therapy is predicated on antimicrobials penetrating into this intracellular growth niche. However, standard antimicrobial susceptibility testing methods test solely for extracellular growth inhibition. Here, we make use of a high-throughput assay to characterize intracellular growth inhibition activity of known antimicrobials. For select antimicrobials, high-resolution dose-response analysis was then performed to characterize and compare activity levels in both macrophage infection and axenic growth assays. Results support the superiority of several classes of nonpolar antimicrobials in abrogating intracellular growth. Importantly, our assay results show excellent correlations with prior clinical observations of antimicrobial efficacy. Furthermore, we also show the applicability of high-throughput automation to two- and three-dimensional synergy testing. High-resolution isocontour isobolograms provide in vitro support for specific combination antimicrobial therapy. Taken together, findings suggest that high-throughput screening technology may be successfully applied to identify and characterize antimicrobials that target bacterial pathogens that make use of an intracellular growth niche. PMID:26392509

Antimicrobial Activity of Kefir against Various Food Pathogens and Spoilage Bacteria

PubMed Central

Kim, Hyunsook

2016-01-01

Kefir is a unique fermented dairy product produced by a mixture of lactic acid bacteria, acetic acid bacteria, and yeast. Here, we compared the antimicrobial spectra of four types of kefirs (A, L, M, and S) fermented for 24, 36, 48, or 72 h against eight food-borne pathogens. Bacillus cereus, Staphylococcus aureus, Listeria monocytogenes, Enterococcus faecalis, Escherichia coli, Salmonella Enteritidis, Pseudomonas aeruginosa, and Cronobacter sakazakii were used as test strains, and antibacterial activity was investigated by the spot on lawn method. The spectra, potencies, and onsets of activity varied according to the type of kefir and the fermentation time. The broadest and strongest antimicrobial spectrum was obtained after at least 36-48 h of fermentation for all kefirs, although the traditional fermentation method of kefir is for 18-24 h at 25℃. For kefir A, B. cereus, E. coli, S. Enteritidis, P. aeruginosa, and C. sakazakii were inhibited, while B. cereus, S. aureus, E. coli, S. Enteritidis, P. aeruginosa, and C. sakazakii were inhibited to different extents by kefirs L, M, and S. Remarkably, S. aureus, S. Enteritidis, and C. sakazakii were only inhibited by kefirs L, M, and S, and L. monocytogenes by kefir M after fermentation for specific times, suggesting that the antimicrobial activity is attributable not only to a low pH but also to antimicrobial substances secreted during the fermentation. PMID:28115890

The rhizospheres of traditional medicinal plants in Panxi, China, host a diverse selection of actinobacteria with antimicrobial properties.

PubMed

Zhao, Ke; Penttinen, Petri; Chen, Qiang; Guan, Tongwei; Lindström, Kristina; Ao, Xiaoling; Zhang, Lili; Zhang, Xiaoping

2012-06-01

Actinobacteria are a prolific source of antibiotics. Since the rate of discovery of novel antibiotics is decreasing, actinobacteria from unique environments need to be explored. In particular, actinobacterial biocontrol strains from medicinal plants need to be studied as they can be a source of potent antibiotics. We combined culture-dependent and culture-independent methods in analyzing the actinobacterial diversity in the rhizosphere of seven traditional medicinal plant species from Panxi, China, and assessed the antimicrobial activity of the isolates. Each of the plant species hosted a unique set of actinobacterial strains. Out of the 64 morphologically distinct isolates, half were Streptomyces sp., eight were Micromonospora sp., and the rest were members of 18 actinobacterial genera. In particular, Ainsliaea henryi Diels. hosted a diverse selection of actinobacteria, although the 16S ribosomal RNA (rRNA) sequence identity ranges of the isolates and of the 16S rRNA gene clone library were not congruent. In the clone library, 40% of the sequences were related to uncultured actinobacteria, emphasizing the need to develop isolation methods to assess the full potential of the actinobacteria. All Streptomyces isolates showed antimicrobial activity. While the antimicrobial activities of the rare actinobacteria were limited, the growth of Escherichia coli, Verticillium dahliae, and Fusarium oxysporum were inhibited only by rare actinobacteria, and strains related to Saccharopolyspora shandongensis and Streptosporangium roseum showed broad antimicrobial activity.

Antimicrobial Activity of Kefir against Various Food Pathogens and Spoilage Bacteria.

PubMed

Kim, Dong-Hyeon; Jeong, Dana; Kim, Hyunsook; Kang, Il-Byeong; Chon, Jung-Whan; Song, Kwang-Young; Seo, Kun-Ho

2016-01-01

Kefir is a unique fermented dairy product produced by a mixture of lactic acid bacteria, acetic acid bacteria, and yeast. Here, we compared the antimicrobial spectra of four types of kefirs (A, L, M, and S) fermented for 24, 36, 48, or 72 h against eight food-borne pathogens. Bacillus cereus , Staphylococcus aureus , Listeria monocytogenes , Enterococcus faecalis , Escherichia coli , Salmonella Enteritidis , Pseudomonas aeruginosa , and Cronobacter sakazakii were used as test strains, and antibacterial activity was investigated by the spot on lawn method. The spectra, potencies, and onsets of activity varied according to the type of kefir and the fermentation time. The broadest and strongest antimicrobial spectrum was obtained after at least 36-48 h of fermentation for all kefirs, although the traditional fermentation method of kefir is for 18-24 h at 25℃. For kefir A, B. cereus , E. coli , S . Enteritidis, P. aeruginosa , and C. sakazakii were inhibited, while B. cereus , S. aureus , E. coli , S . Enteritidis, P. aeruginosa , and C. sakazakii were inhibited to different extents by kefirs L, M, and S. Remarkably, S. aureus , S . Enteritidis, and C. sakazakii were only inhibited by kefirs L, M, and S, and L. monocytogenes by kefir M after fermentation for specific times, suggesting that the antimicrobial activity is attributable not only to a low pH but also to antimicrobial substances secreted during the fermentation.

Antimicrobial potential of selected brown seaweeds from Vedalai coastal waters, Gulf of Mannar

PubMed Central

Manivannan, K; Karthikai devi, G; Anantharaman, P; Balasubramanian, T

2011-01-01

Objective To evaluate the antimicrobial activity of Turbinaria conoides (T. conoides), Padina gymnospora (P. gymnospora) and Sargassum tenerrimum against human bacterial and fungal pathogens. Methods The antimicrobial activities of the extracts against various organisms were tested by using disc diffusion method. Results The methanol extract showed the better result than the other extracts. Whereas, the strong antibacterial inhibition was noted in methanol extracts of P. gymnospora against Bacillus subtilus (26.33±1.86) and the mild inhibition of ethanol extracts from T. conoides against Klebsiella pneumoniae (2.33±0.51). Acetone extraction of P. gymnospora had strong antifungal inhibition against Cryptococcus neoformans (23.00±1.78), and acetone extract of T. conoides had mild inhibition against Aspergillus niger (3.00±0.89). Conclusions The seven different solvent extracts of seaweeds used in the present study have shown significant bacterial action. Further, a detailed study on the principle compound in the seaweeds which is responsible for antimicrobial activity is still needed and it can be achieved by using advanced separation techniques. PMID:23569739

In Vitro Evaluation of Antioxidant and Antimicrobial Activities of Melaleuca alternifolia Essential Oil

PubMed Central

Zhang, Xiaofeng; Guo, Yanjun; Guo, Liying; Jiang, Hui

2018-01-01

The in vitro antioxidant and antimicrobial activity of the essential oil from Melaleuca alternifolia (M. alternifolia) was evaluated in this report. The antioxidant potential of the essential oil from M. alternifolia was evaluated by the DPPH (2,2-diphenyl-1-picrylhydrazyl) method, thiobarbituric acid reactive species (TBARS) assay, and the hydroxyl radical scavenging activity method. The essential oil from M. alternifolia was able to reduce DPPH with an EC50 (concentration for 50% of maximal effect) of 48.35 μg/ml, inhibit the lipid peroxidation with an IC50 (50% inhibitory concentration) of 135.9 μg/ml, and eliminate hydroxyl radicals with an EC50 of 43.71 μg/ml. Antimicrobial screening, minimum inhibitory concentration, and minimum bactericidal concentration assays showed that the essential oil from M. alternifolia inhibited strongly the growth of different types of microorganisms, including Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Penicillium italicum Wehmer, and Penicillium digitatum Sacc. Thus, the essential oil of M. alternifolia possesses antioxidant and antimicrobial activity and could be suitable for use as a natural preservative ingredient in food, agriculture, and pharmaceutical industries. PMID:29854733

Antimicrobial and anti-adherence activity of various combinations of coffee-chicory solutions on Streptococcus mutans: An in-vitro study

PubMed Central

Sharma, Rama; Reddy, Vamsi Krishna L; Prashant, GM; Ojha, Vivek; Kumar, Naveen PG

2014-01-01

Context: Several studies have demonstrated the activity of natural plants on the dental biofilm and caries development. But few studies on the antimicrobial activity of coffee-based solutions were found in the literature. Further there was no study available to check the antimicrobial effect of coffee solutions with different percentages of chicory in it. Aims: To evaluate the antimicrobial activity of different combinations of coffee-chicory solutions and their anti-adherence effect on Streptococcus mutans to glass surface. Materials and Methods: Test solutions were prepared. For antimicrobial activity testing, tubes containing test solution and culture medium were inoculated with a suspension of S. mutans followed by plating on Brain Heart Infusion (BHI) agar. S. mutans adherence to glass in presence of the different test solutions was also tested. The number of adhered bacteria (CFU/mL) was determined by plating method. Statistical Analysis: Statistical significance was measured using one way ANOVA followed by Tukey's post hoc test. P value < 0.05 was considered statistically significant. Results: Pure chicory had shown significantly less bacterial count compared to all other groups. Groups IV and V had shown significant reduction in bacterial counts over the period of 4 hrs. Regarding anti-adherence effect, group I-IV had shown significantly less adherence of bacteria to glass surface. Conclusions: Chicory exerted antibacterial effect against S. mutans while coffee reduced significantly the adherence of S. mutans to the glass surface. PMID:25328299

Quantitative analysis of catechins in Saraca asoca and correlation with antimicrobial activity

PubMed Central

Shirolkar, Amey; Gahlaut, Anjum; Chhillar, Anil K.; Dabur, Rajesh

2013-01-01

Herbal medicines are highly complex and have unknown mechanisms in diseases treatment. Saraca asoca (Roxb.), De. Wild has been recommended to treat gynecological disorders and used in several commercial polyherbal formulations. In present study, efforts have been made to explore antimicrobial activity and its co-relation with the distributions of catechins in the organs of S. asoca using targeted MS/MS. Eight extracts (cold and hot water) from four different organs of S. asoca and two drugs were prepared and antimicrobial activity was assessed by microbroth dilution assay. Quantitative and qualitative analysis of catechins in crude extracts was done by using targeted and auto-MS/MS and correlated with antimicrobial activity. (+)-Catechin and (+)-epicatechin and their biosynthesis related compound were found to be up-regulated in regenerated bark and leaves extracts. (−)-Epigallocatechin was found to be significantly higher in bark water extract as compared to others but showed low antimicrobial activity. Result showed down-regulation of (−)-epigallocatechin and up-regulation of (+)-catechin and (+)-epicatechin in the regenerated bark and leaves of S. asoca. It might be the contributing factor in the antimicrobial activity of regenerated bark and leaves of the plant. The concentration of (+)-epicatechin in processed drugs (Ashokarishta) from Baidyanath was found to be seven times higher than that of Dabur Pvt. Ltd., but no antimicrobial activity was observed, indicating the variations among the plant based drugs. This will be helpful in rational use of S. asoca parts. Furthermore, the analytical method developed is sensitive, repeatable and reliable; therefore, it is suitable for quality control of herbal drugs. PMID:29403849

Comparison of antimicrobial activities of naphthoquinones from Impatiens balsamina.

PubMed

Sakunphueak, Athip; Panichayupakaranant, Pharkphoom

2012-01-01

Lawsone (1), lawsone methyl ether (2), and methylene-3,3'-bilawsone (3) are the main naphthoquinones in the leaf extracts of Impatiens balsamina L. (Balsaminaceae). Antimicrobial activities of these three naphthoquinones against dermatophyte fungi, yeast, aerobic bacteria and facultative anaerobic and anaerobic bacteria were evaluated by determination of minimal inhibitory concentrations (MICs) and minimal bactericidal or fungicidal concentrations (MBCs or MFCs) using a modified agar dilution method. Compound 2 showed the highest antimicrobial activity. It showed antifungal activity against dermatophyte fungi and Candida albicans with the MICs and MFCs in the ranges of 3.9-23.4 and 7.8-23.4 µg mL(-1), respectively, and also had some antibacterial activity against aerobic, facultative anaerobic and anaerobic bacteria with MICs in the range of 23.4-93.8, 31.2-62.5 and 125 µg mL(-1), respectively. Compound 1 showed only moderate antimicrobial activity against dermatophytes (MICs and MFCs in the ranges of 62.5-250 and 125-250 µg mL(-1), respectively), but had low potency against aerobic bacteria, and was not active against C. albicans and facultative anaerobic bacteria. In contrast, 3 showed significant antimicrobial activity only against Staphylococus epidermidis and Bacillus subtilis (MIC and MBC of 46.9 and 93.8 µg mL(-1), respectively).

A Rapid and Quantitative Flow Cytometry Method for the Analysis of Membrane Disruptive Antimicrobial Activity.

PubMed

O'Brien-Simpson, Neil M; Pantarat, Namfon; Attard, Troy J; Walsh, Katrina A; Reynolds, Eric C

2016-01-01

We describe a microbial flow cytometry method that quantifies within 3 hours antimicrobial peptide (AMP) activity, termed Minimum Membrane Disruptive Concentration (MDC). Increasing peptide concentration positively correlates with the extent of bacterial membrane disruption and the calculated MDC is equivalent to its MBC. The activity of AMPs representing three different membranolytic modes of action could be determined for a range of Gram positive and negative bacteria, including the ESKAPE pathogens, E. coli and MRSA. By using the MDC50 concentration of the parent AMP, the method provides high-throughput, quantitative screening of AMP analogues. A unique feature of the MDC assay is that it directly measures peptide/bacteria interactions and lysed cell numbers rather than bacteria survival as with MIC and MBC assays. With the threat of multi-drug resistant bacteria, this high-throughput MDC assay has the potential to aid in the development of novel antimicrobials that target bacteria with improved efficacy.

Antimicrobial effect of 7-O-butylnaringenin, a novel flavonoid, and various natural flavonoids against Helicobacter pylori strains.

PubMed

Moon, Sun Hee; Lee, Jae Hoon; Kim, Kee-Tae; Park, Yong-Sun; Nah, Seung-Yeol; Ahn, Dong Uk; Paik, Hyun-Dong

2013-10-28

The antimicrobial effect of a novel flavonoid (7-O-butylnaringenin) on Helicobacter pylori 26695, 51, and SS1 strains and its inhibitory effect on the urease activity of the strains were evaluated and compared with those of several natural flavonoids. First, various flavonoids were screened for antimicrobial activities using the paper disc diffusion method. Hesperetin and naringenin showed the strongest antimicrobial effects among the natural flavonoids tested, and thus hesperetin and naringenin were selected for comparison with 7-O-butylnaringenin. The antimicrobial effect of 7-O-butylnaringenin was greater than that of the hesperetin and naringenin. H. pylori 51 was more sensitive to 7-O-butylnaringenin (2 log reduction of colony forming units, p < 0.05) than the other two strains at 200 μM. 7-O-Butylnaringenin also showed the highest inhibitory effect against urease activity of H. pylori. Morphological changes of H. pylori 26695 treated with these flavonoids indicated that both hesperetin and 7-O-butylnaringenin at 200 μM damaged the cell membranes.

Organogel-nanoemulsion containing nisin and D-limonene and its antimicrobial activity

PubMed Central

Bei, Weiya; Zhou, Yan; Xing, Xuya; Zahi, Mohamed Reda; Li, Yuan; Yuan, Qipeng; Liang, Hao

2015-01-01

The aim of this study was to investigate a novel delivery system containing D-limonene and nisin by food organogel-nanoemulsion and study its effect on the antimicrobial activity. Organogel-nanoemulsion containing with D-limonene and nisin or without nisin was prepared by a homogenization method. Factors that may affect the droplet size and stability of organogel-nanoemulsion such as pressure and surfactant to oil ratio (SOR) were studied. The average droplet size decreased with pressure, and the organogel-nanoemulsion could achieve good stability at low SOR. Positive effects and outstanding antimicrobial activities of organogel-nanoemulsion containing with D-limonene and nisin were confirmed by minimal inhibitory concentrations comparison, growth curves of bacteria, scanning electron microscopy and determination of cell constituents’ release. Furthermore, the organogel-nanoemulsion applied as food preservative in milk also shown excellent antimicrobial performance. Overall, the research described in the current article show that organogel-nanoemulsion containing with D-limonene and nisin may be an effective antimicrobial system for the production and preservation of food. PMID:26441935

Influence of extraction methods on antioxidant and antimicrobial properties of essential oil from Thymua danesis subsp. Lancifolius.

PubMed

Tavakolpour, Yousef; Moosavi-Nasab, Marzieh; Niakousari, Mehrdad; Haghighi-Manesh, Soroush

2016-03-01

The essential oil (EO) from dried ground powder leaves and stems of Thymua danesis was extracted using hydrodistillation (HD), ohmic extraction (OE), ultrasound-assisted HD and ultrasound-assisted OE methods. Then, the antioxidant, antimicrobial, and sensory properties of the EO were investigated both in vitro and in food systems. Thyme EO extracted by ultrasound-assisted HD method had promising antibacterial activities against Escherichia coli and Staphylococcus aureus and had the best antioxidant properties when tested in vitro. In food systems, higher concentrations of the EO were needed to exert similar antibacterial and antioxidant effects. Furthermore, thyme EO added yogurt and drink yogurt revealed better sensory properties than the control and fresh samples. Essential oil from Thymua danesis has a good potential to be used as an antioxidant, antimicrobial, and flavoring agent in food systems and the extraction method effects on the antioxidant and antimicrobial properties of the thyme extract.

Antimicrobial activity of isothiocyanates (ITCs) extracted from horseradish (Armoracia rusticana) root against oral microorganisms.

PubMed

Park, Ho-Won; Choi, Kyu-Duck; Shin, Il-Shik

2013-01-01

The antimicrobial activity of isothiocyanates (ITCs) extracted from horseradish root was investigated against oral microorganisms: 6 strains of facultative anaerobic bacteria, Streptococcus mutans, Streptococcus sobrinus, Lactobacillus casei, Staphylococcus aureus, Enterococcus faecalis and Aggregatibacter actinomycetemcomitans; one strain of yeast, Candida albicans, and 3 strains of anaerobic bacteria, Fusobacterium nucleatum, Prevotella nigrescens, and Clostridium perfringens. The ITCs extracted from horseradish root showed antimicrobial activity against all oral microorganisms by the paper disk method. The minimum bactericidal concentration (MBC) of the ITCs extracted from horseradish root ranged from 1.25 to 5.00 mg/ml against 6 strains of facultative anaerobic bacteria and one strain of yeast, and 4.17 to 16.67 mg/ml against 3 strains of anaerobic bacteria. The ITCs extracted from horseradish root showed the strongest antimicrobial activity, with a MBC of 1.25 mg/ml, against C. albicans among facultative microorganisms, and 4.17 mg/ml against F. nucleatum among anaerobic bacteria. These results suggest that the ITCs extracted from horseradish root may be a candidate for use as an antimicrobial agent against oral microorganisms.

A simple and low-cost platform technology for producing pexiganan antimicrobial peptide in E. coli.

PubMed

Zhao, Chun-Xia; Dwyer, Mirjana Dimitrijev; Yu, Alice Lei; Wu, Yang; Fang, Sheng; Middelberg, Anton P J

2015-05-01

Antimicrobial peptides, as a new class of antibiotics, have generated tremendous interest as potential alternatives to classical antibiotics. However, the large-scale production of antimicrobial peptides remains a significant challenge. This paper reports a simple and low-cost chromatography-free platform technology for producing antimicrobial peptides in Escherichia coli (E. coli). A fusion protein comprising a variant of the helical biosurfactant protein DAMP4 and the known antimicrobial peptide pexiganan is designed by joining the two polypeptides, at the DNA level, via an acid-sensitive cleavage site. The resulting DAMP4(var)-pexiganan fusion protein expresses at high level and solubility in recombinant E. coli, and a simple heat-purification method was applied to disrupt cells and deliver high-purity DAMP4(var)-pexiganan protein. Simple acid cleavage successfully separated the DAMP4 variant protein and the antimicrobial peptide. Antimicrobial activity tests confirmed that the bio-produced antimicrobial peptide has the same antimicrobial activity as the equivalent product made by conventional chemical peptide synthesis. This simple and low-cost platform technology can be easily adapted to produce other valuable peptide products, and opens a new manufacturing approach for producing antimicrobial peptides at large scale using the tools and approaches of biochemical engineering. © 2014 Wiley Periodicals, Inc.

Antibacterial activity of fresh pomegranate juice against clinical strains of Staphylococcus epidermidis

PubMed Central

Betanzos-Cabrera, Gabriel; Montes-Rubio, Perla Y.; Fabela-Illescas, Héctor E.; Belefant-Miller, Helen; Cancino-Diaz, Juan C.

2015-01-01

Background Polyphenols have received a great deal of attention due to their biological functions. Pomegranate (Punica granatum L.) is a polyphenol-rich fruit. In the past decade, studies testing the antimicrobial activity of pomegranates almost exclusively used solvent extracts instead of fresh pomegranate juice (FPJ). The use of FPJ instead of solvent extracts would reduce toxicity issues while increasing patient acceptance. We established a model to test FPJ as a natural antimicrobial agent. Objective To evaluate the antimicrobial activity of FPJ on clinical isolates of multidrug-resistant Staphylococcus epidermidis strains. Design Sixty strains of S. epidermidis isolated from ocular infections were grown in the presence of FPJ, and minimum inhibitory concentration (MIC) was determined by broth and agar dilution methods. Results FPJ at 20% had a MIC equal to 100% (MIC100%) on all 60 strains tested. This inhibition of FPJ was confirmed by the growth kinetics of a multidrug-resistant strain exposed to different concentrations of FPJ. Additionally, the antimicrobial activity of FPJ was compared against commercial beverages containing pomegranate: Ocean Spray® had a MIC100% at 20%, followed by Del Valle® with a MIC15% at 20% concentration only. The beverages Jumex® and Sonrisa® did not have any antimicrobial activity. FPJ had the highest polyphenol content and antioxidant capacity. Conclusions Overall, FPJ had antimicrobial activity, which might be attributed to its high polyphenol content and antioxidant capacity. PMID:25999265

Antifungal and antibacterial activity of marine microorganisms.

PubMed

El Amraoui, B; El Amraoui, M; Cohen, N; Fassouane, A

2014-03-01

In order to explore marine microorganisms with pharmaceutical potential, marine bacteria, collected from different coastal areas of the Moroccan Atlantic Ocean, were previously isolated from seawater, sediment, marine invertebrates and seaweeds. The antimicrobial activities of these microorganisms were investigated against the pathogens involved in human pathologies. Whole cultures of 34 marine microorganisms were screened for antimicrobial activities using the method of agar diffusion against three Gram-positive bacteria, two Gram-negative bacteria, and against yeast. The results showed that among the 34 isolates studied, 28 (82%) strains have antimicrobial activity against at least one pathogen studied, 11 (32%) strains have antifungal activity and 24 (76%) strains are active against Gram-positive bacteria, while 21 (62%) strains are active against Gram-negative bacteria. Among isolates having antimicrobial activity, 14 were identified and were assigned to the genera Acinetobacter, Aeromonas, Alcaligenes, Bacillus, Chromobacterium, Enterococcus, Pantoea and Pseudomonas. Due to a competitive role for space and nutrient, the marine microorganisms can produce antibiotic substance; therefore, these marine microorganisms were expected to be potential resources of natural antibiotic products. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

Fabrication, characterization and in vitro evaluation of silibinin nanoparticles: an attempt to enhance its oral bioavailability

PubMed Central

Sahibzada, Muhammad Umar Khayam; Sadiq, Abdul; Khan, Shahzeb; Faidah, Hani S; Naseemullah; Khurram, Muhammad; Amin, Muhammad Usman; Haseeb, Abdul

2017-01-01

Background Silibinin has gained in importance in the past few decades as a hepatoprotector and is used widely as oral therapy for toxic liver damage, liver cirrhosis, and chronic inflammatory liver diseases, as well as for the treatment of different types of cancers. Unfortunately, it has low aqueous solubility and inadequate dissolution, which results in low oral bioavailability. Materials and methods In this study, nanoparticles (NPs) of silibinin, which is a hydrophobic drug, were manufactured using two cost-effective methods. Antisolvent precipitation with a syringe pump (APSP) and evaporative precipitation of nanosuspension (EPN) were used. The prepared NPs were characterized using different analytical techniques such as scanning electron microscopy (SEM), fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), and X-ray powder diffractometry (XRD) and were sifted for their bioavailability through in vitro dissolution and solubility studies. Moreover, the prepared NPs were evaluated for antimicrobial activity against a battery of bacteria and yeast. Results DSC and XRD studies indicated that the prepared NPs were amorphous in nature, with more solubility and dissolution compared to the crystalline form of this drug. NPs prepared through the EPN method had better results than those prepared using the APSP method. Antimicrobial activities of the NPs were improved compared to the unprocessed drugs, while having comparable activities to standard antimicrobial drugs. Conclusion Results indicate that the NPs have significantly increased solubility, dissolution rate, and antimicrobial activities due to the conversion of crystalline structure into amorphous form. PMID:28553075

In Vitro Antimicrobial Bioassays, DPPH Radical Scavenging Activity, and FTIR Spectroscopy Analysis of Heliotropium bacciferum.

PubMed

Ahmad, Sohail; AbdEl-Salam, Naser M; Ullah, Riaz

2016-01-01

The present study deals with the antimicrobial, antioxidant, and functional group analysis of Heliotropium bacciferum extracts. Disc diffusion susceptibility method was followed for antimicrobial assessment. Noteworthy antimicrobial activities were recorded by various plant extracts against antibiotic resistant microorganisms. Plant flower extracts antioxidant activity was investigated against 2, 2-diphenyl-1-picryl hydrazyl radical by ultraviolet spectrophotometer (517 nm). Plant extracts displayed noteworthy radical scavenging activities at all concentrations (25-225 μg/mL). Notable activities were recorded by crude, chloroform and ethyl acetate extracts up to 88.27% at 225 μg/mL concentration. Compounds functional groups were examined by Fourier transform infrared spectroscopic studies. Alkanes, alkenes, alkyl halides, amines, carboxylic acids, amides, esters, alcohols, phenols, nitrocompounds, and aromatic compounds were identified by FTIR analysis. Thin layer chromatography bioautography was carried out for all plant extracts. Different bands were separated by various solvent systems. The results of the current study justify the use of Heliotropium bacciferum in traditional remedial herbal medicines.

Physicochemical properties and antimicrobial activity of Roselle (Hibiscus sabdariffa L.).

PubMed

Jung, EunKyung; Kim, YoungJun; Joo, Nami

2013-12-01

The therapeutic action of a plant depends on its chemical constituents. In this study, experiments were carried out in order to evaluate the effect of extraction conditions on the antioxidative and antimicrobial activities of Roselle (Hibiscus sabdariffa L.). Roselle was found to be rich in malic acid, anthocyanins, ascorbic acid and minerals, especially Ca and Fe, but low in glucose. More than 18 volatile compounds were identified by gas chromatography and gas chromatography-mass spectrometry. This herb, which is rich in phenolic compounds and displays DPPH radical scavenging activity, could be a good source of natural antioxidants. The antimicrobial activity of the Roselle water and ethanol extracts was tested with Bacillus subtilis (ATCC6633), Staphylococcus aureus (ATCC6538) and Escherichia coli (ATCC 8739). The inhibition of the Roselle ethanol extract against B. subtilis and S. aureus was slightly higher than that of water extract but this difference was not significant. However, E. coli was strongly inhibited by the Roselle water extract at concentrations of 25 and 50 mg mL(-1) as determined by a paper disc method. The obtained results indicated that antioxidant and antimicrobial activity was related to different methods of extraction and Roselle extracts could be a source of therapeutically useful products. © 2013 Society of Chemical Industry.

Synthesis, anti-microbial and molecular docking studies of quinazolin-4(3H)-one derivatives.

PubMed

Mabkhot, Yahia Nasser; Al-Har, Munirah S; Barakat, Assem; Aldawsari, Fahad D; Aldalbahi, Ali; Ul-Haq, Zaheer

2014-06-25

In this work, synthesis, antimicrobial activities and molecular docking studies of some new series of substituted quinazolinone 2a-h and 3a-d were described. Starting form 2-aminobenzamide derivatives 1, a new series of quinazolinone derivatives has been synthesized, in high yields, assisted by microwave and classical methods. Some of these substituted quinazolinones were tested for their antimicrobial activity against Gram-negative bacteria (Pseudomonas aeruginosa and Esherichia coli) and Gram-positive bacteria (Staphylococcus aureus, and Bacillus subtilis), and anti-fungal activity against (Aspergillus fumigatus, Saccharomyces cervevisiae, and Candida albicans) using agar well diffusion method. Among the prepared products, 3-benzyl-2-(4-chlorophenyl)quinazolin-4(3H)-one (3a) was found to exhibits the most potent in vitro anti-microbial activity with MICs of 25.6±0.5, 24.3±0.4, 30.1±0.6, and 25.1±0.5 µg/mL against Staphylococcus aureus, Bacillus subtilis, Pseudomonas aeruginosa and Esherichia coli, respectively. Compound 3a was found to exhibits the most potent in vitro anti-fungal activity with MICs of 18.3±0.6, 23.1±0.4, and 26.1±0.5 µg/mL against Aspergillus fumigatus, Saccharomyces cervevisiae, and Candidaal bicans, respectively.

The comparison of antimicrobial packaging properties with different applications incorporation method of active material

NASA Astrophysics Data System (ADS)

Anwar, R. W.; Sugiarto; Warsiki, E.

2018-03-01

Contamination after the processing of products during storage, distribution and marketing is one of the main causes of food safety issues. Handling of food products after processing can be done during the packaging process. Antimicrobial (AM) active packaging is one of the concept of packaging product development by utilize the interaction between the product and the packaging environment that can delay the bacterial damage by killing or reducing bacterial growth. The active system is formed by incorporating an antimicrobial agent against a packaging matrix that will function as a carrier. Many incorporation methods have been developed in this packaging-making concept which were direct mixing, polishing, and encapsulation. The aims of this research were to examine the different of the AM packaging performances including its stability and effectiveness of its function that would be produced by three different methods. The stability of the packaging function was analyzed by looking at the diffusivity of the active ingredient to the matrix using SEM. The effectiveness was analyzed by the ability of the packaging to prevent the growing of the microbial. The results showed that different incorporation methods resulted on different characteristics of the AM packaging.

Antimicrobial Activity and Phytochemical Analysis of Organic Extracts from Cleome spinosa Jaqc.

PubMed Central

da Silva, Ana P. Sant'Anna; Nascimento da Silva, Luís C.; Martins da Fonseca, Caíque S.; de Araújo, Janete M.; Correia, Maria T. dos Santos; Cavalcanti, Marilene da Silva; Lima, Vera L. de Menezes

2016-01-01

Due to the use of Cleome spinosa Jacq. (Cleomaceae) in traditional medicine against inflammatory and infectious processes, this study evaluated the in vitro antimicrobial potential and phytochemical composition of extracts from its roots and leaves. From leaves (L) and roots (R) of C. spinosa different extracts were obtained (cyclohexane: ChL and ChR; chloroform: CL and CR; ethyl acetate: EAL and EAR, methanol: ML and MR). The antimicrobial activity was evaluated by the broth microdilution method to obtain the minimum inhibitory (MIC) and microbicidal (MMC) concentrations against 17 species, including bacteria and yeasts. Additionally, antimicrobial and combinatory effects with oxacillin were assessed against eight clinical isolates of Staphylococcus aureus. All C. spinosa extracts showed a broad spectrum of antimicrobial activity, as they have inhibited all tested bacteria and yeasts. This activity seems to be related to the phytochemicals (flavonoid, terpenoids and saponins) detected into the extracts of C. spinosa. ChL and CL extracts were the most actives, with MIC less than 1 mg/mL against S. aureus, Bacillus subtilis, and Micrococcus luteus. It is important to note that these concentrations are much lower than their 50% hemolysis concentration (HC50) values. Strong correlations were found between the average MIC against S. aureus and their phenolic (r = −0.89) and flavonoid content (r = −0.87), reinforcing the possible role of these metabolite classes on the antimicrobial activity of C. spinosa derived extracts. Moreover, CL and CR showed the best inhibitory activity against S. aureus clinical isolates, they also showed synergistic action with oxacillin against all these strains (at least at one combined proportion). These results encourage the identification of active substances which could be used as lead(s) molecules in the development of new antimicrobial drugs. PMID:27446005

Strategies for transformation of naturally-occurring amphibian antimicrobial peptides into therapeutically valuable anti-infective agents.

PubMed

Conlon, J Michael; Al-Ghaferi, Nadia; Abraham, Bency; Leprince, Jérôme

2007-08-01

The emergence of strains of pathogenic microorganisms with resistance to commonly used antibiotics has necessitated a search for novel types of antimicrobial agents. Many frog species produce amphipathic alpha-helical peptides with broad spectrum antimicrobial activity in the skin but their therapeutic potential is limited by varying degrees of cytolytic activity towards eukaryotic cells. Methods for development of such peptides into anti-infective drugs are illustrated by the example of temporin-1DRa (HFLGTLVNLAK KIL.NH(2)). Studies with model alpha-helical peptides have shown that increase in cationicity promotes antimicrobial activity whereas increases in hydrophobicity, helicity and amphipathicity promote hemolytic activity and loss of selectivity for microorganisms. Analogs of temporin-1DRa in which each amino acid is replaced by L-lysine and D-lysine were synthesized and their cytolytic activities tested against a range of microorganisms and human erythrocytes. Small changes in structure produced marked changes in conformation, as determined by retention time on reversed-phase HPLC, and in biological activity. However, peptides containing the substitutions (Val(7) -->L-Lys), (Thr(5)-->D-Lys) and (Asn(8)-->D-Lys) retained the high solubility and potent, broad spectrum antimicrobial activity of the naturally occurring peptide but were appreciably (up to 10-fold) less hemolytic. In contrast, analogs in which Leu(9) and Ile(13) were replaced by the more hydrophobic cyclohexylglycine residue showed slightly increased antimicrobial potencies (up to 2-fold) but a 4-fold increase in hemolytic activity. The data suggest a strategy of selective increases in cationicity concomitant with decreases in helicity and hydrophobicity in the transformation of naturally-occurring antimicrobial peptides into non-toxic therapeutic agents.

Antimicrobial activity of yeasts against some pathogenic bacteria

PubMed Central

Younis, Gamal; Awad, Amal; Dawod, Rehab E.; Yousef, Nehal E.

2017-01-01

Aim: This study was designed to isolate and identify yeast species from milk and meat products, and to test their antimicrobial activity against some bacterial species. Materials and Methods: A total of 160 milk and meat products samples were collected from random sellers and super markets in New Damietta city, Damietta, Egypt. Samples were subjected to yeast isolation procedures and tested for its antimicrobial activity against Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli. In addition, all yeast species isolates were subjected to polymerase chain reaction (PCR) for detection of khs (kievitone hydratase) and pelA (pectate degrading enzyme)genes. Results: The recovery rate of yeasts from sausage was 20% (2/10) followed by kareish cheese, processed cheese, and butter 10% (1/10) each as well as raw milk 9% (9/100), and fruit yoghurt 30% (6/20). Different yeast species were recovered, namely, Candida kefyr (5 isolates), Saccharomyces cerevisiae (4 isolates), Candida intermedia (3 isolates), Candida tropicalis (2 isolates), Candida lusitaniae (2 isolates), and Candida krusei (1 isolate). khs gene was detected in all S. cerevisiae isolates, however, pelA gene was not detected in all identified yeast species. Antimicrobial activity of recovered yeasts against the selected bacterial species showed high activity with C. intermedia against S. aureus and E. coli, C. kefyr against E. coli, and C. lusitaniae against S. aureus. Moderate activities were obtained with C. tropicalis, C. lusitaniae, and S. cerevisiae against E. coli; meanwhile, all the tested yeasts revealed a very low antimicrobial activity against P. aeruginosa. Conclusion: The obtained results confirmed that some kinds of yeasts have the ability to produce antimicrobial compounds that could inhibit some pathogenic and spoilage bacteria and these antimicrobial activity of yeasts enables them to be one of the novel agents in controlling spoilage of food. PMID:28919693

Development of an Antimicrobial Stewardship-based Infectious Diseases Elective that Incorporates Human Patient Simulation Technology

PubMed Central

Meyer, Susan M.

2014-01-01

Objective. To design an elective for pharmacy students that facilitates antimicrobial stewardship awareness, knowledge, and skill development by solving clinical cases, using human patient simulation technology. Design. The elective was designed for PharmD students to describe principles and functions of stewardship programs, select, evaluate, refine, or redesign patient-specific plans for infectious diseases in the context of antimicrobial stewardship, and propose criteria and stewardship management strategies for an antimicrobial class at a health care institution. Teaching methods included active learning and lectures. Cases of bacterial endocarditis and cryptococcal meningitis were developed that incorporated human patient simulation technology. Assessment. Forty-five pharmacy students completed an antimicrobial stewardship elective between 2010 and 2013. Outcomes were assessed using student perceptions of and performance on rubric-graded assignments. Conclusion. A PharmD elective using active learning, including novel cases conducted with human patient simulation technology, enabled outcomes consistent with those desired of pharmacists assisting in antimicrobial stewardship programs. PMID:25386016

Effect of potassium sorbate on antimicrobial and physical properties of starch-clay nanocomposite films.

PubMed

Barzegar, Hassan; Azizi, Mohammad Hossein; Barzegar, Mohsen; Hamidi-Esfahani, Zohreh

2014-09-22

Using fresh foods which undergo the least processing operations developed widely in recent years. Active packaging is a novel method for preserving these products. Active starch-clay nanocomposite films which contained potassium sorbate (PS) at a level of 0, 5, 7.5 and 10 g PS/100 g starch were produced and their physical, mechanical and antimicrobial properties were evaluated. In order to evaluate antimicrobial properties of films Aspergillus niger was used. The results showed that 5% of the PS did not produce antimicrobial property in the film, but by increasing the content of the additive in film formulation, antimicrobial effect increased. PS increased water permeability and elongation at break of the films, but decreased tensile strength. The rate of PS migration into the semi-solid medium in starch-nanocomposites was lower than starch films. This shows that nanocomposite films could retain their antimicrobial property for longer time. Copyright © 2014 Elsevier Ltd. All rights reserved.

Antimicrobial activity of silver nanoparticles impregnated wound dressing

NASA Astrophysics Data System (ADS)

Shinde, V. V.; Jadhav, P. R.; Patil, P. S.

2013-06-01

In this work, silver nanoparticles were synthesized by simple wet chemical reduction method. The silver nitrate was reduced by Sodium borohydride used as reducing agent and Poly (vinyl pyrrolidone) (PVP) as stabilizing agent. The formation of silver nanoparticles was evaluated by UV-visible spectroscope and transmission electron microscope (TEM). Absorption spectrum consist two plasmon peaks at 410 and 668 nm revels the formation of anisotropic nanoparticles confirmed by TEM. The formation of silver nanoparticles was also evidenced by dynamic light scattering (DLS) study. DLS showed polydisperse silver nanoparticles with hydrodynamic size 32 nm. Protecting mechanism of PVP was manifested by FT-Raman study. Silver nanoparticles were impregnated into wound dressing by sonochemical method. The Kirby-Bauer disc diffusion methods were used for antimicrobial susceptibility testing. The antimicrobial activity of the samples has been tested against gram-negative bacterium Escherichia coli and gram-positive bacterium Staphylococcus aureus.

Two choices for the functionalization of silica nanoparticles with gallic acid: characterization of the nanomaterials and their antimicrobial activity against Paenibacillus larvae

NASA Astrophysics Data System (ADS)

Vico, Tamara A.; Arce, Valeria B.; Fangio, María F.; Gende, Liesel B.; Bertran, Celso A.; Mártire, Daniel O.; Churio, María S.

2016-11-01

Silica nanoparticles attached to gallic acid were synthesized from 7-nm diameter fumed silica particles by different functionalization methods involving the condensation of hydroxyl or carboxyl groups. The particles were characterized by thermal analyses and UV-vis, FTIR, NMR, and EPR spectroscopies. In comparison to free gallic acid, enhanced stability and increased antimicrobial activity against Paenibacillus larvae were found for the functionalized nanoparticles. Thus, both derivatization strategies result in improved properties of the natural polyphenol as antimicrobial agent for the treatment of honeybee pathologies.

Sesquiterpene Lactones from Gynoxys verrucosa and their Anti-MRSA Activity

PubMed Central

Ordóñez, Paola E.; Quave, Cassandra L.; Reynolds, William F.; Varughese, Kottayil I.; Berry, Brian; Breen, Philip J.; Malagón, Omar; Smeltzer, Mark S.; Compadre, Cesar M.

2011-01-01

Ethnopharmacological relevance Because of its virulence and antibiotic resistance, Staphylococcus aureus is a more formidable pathogen now than at any time since the pre-antibiotic era. In an effort to identify and develop novel antimicrobial agents with activity against this pathogen, we have examined Gynoxys verrucosa Wedd (Asteraceae), an herb used in traditional medicine in southern Ecuador for the treatment and healing of wounds. Materials and Methods The sesquiterpene lactones leucodine (1) and dehydroleucodine (2) were extracted and purified from the aerial parts of G. verrucosa, and their structure was elucidated by spectroscopic methods and single-crystal X-ray analysis. The in vitro anti-microbial activity of G. verrucosa extracts and its purified constituents was determined against six clinical isolates including S. aureus and Staphylococcus epidermidis strains with different drug-resistance profiles, using the microtiter broth method. Results Compound 1 has very low activity, while compound 2 has moderate activity with MIC50s between 49 and195 μg/mL. The extract of G. verrucosa has weak activity with MIC50s between 908 and 3290 μg/mL. Conclusions We are reporting the full assignment of the 1H-NMR and 13C-NMR of both compounds, and the crystal structure of compound 2, for the first time. Moreover, the fact that compound 2 has antimicrobial activity and compound 1 does not, demonstrates that the exocyclic conjugated methylene in the lactone ring is essential for the antimicrobial activity of these sesquiterpene lactones. However, the weak activity observed for the plants extracts, does not explain the use of G. verrucosa in traditional medicine for the treatment of wounds and skin infections. PMID:21782013

A Report of the Efforts of the Veterans Health Administration National Antimicrobial Stewardship Initiative.

PubMed

Kelly, Allison A; Jones, Makoto M; Echevarria, Kelly L; Kralovic, Stephen M; Samore, Matthew H; Goetz, Matthew B; Madaras-Kelly, Karl J; Simbartl, Loretta A; Morreale, Anthony P; Neuhauser, Melinda M; Roselle, Gary A

2017-05-01

OBJECTIVE To detail the activities of the Veterans Health Administration (VHA) Antimicrobial Stewardship Initiative and evaluate outcomes of the program. DESIGN Observational analysis. SETTING The VHA is a large integrated healthcare system serving approximately 6 million individuals annually at more than 140 medical facilities. METHODS Utilization of nationally developed resources, proportional distribution of antibiotics, changes in stewardship practices and patient safety measures were reported. In addition, inpatient antimicrobial use was evaluated before and after implementation of national stewardship activities. RESULTS Nationally developed stewardship resources were well utilized, and many stewardship practices significantly increased, including development of written stewardship policies at 92% of facilities by 2015 (P<.05). While the proportional distribution of antibiotics did not change, inpatient antibiotic use significantly decreased after VHA Antimicrobial Stewardship Initiative activities began (P<.0001). A 12% decrease in antibiotic use was noted overall. The VHA has also noted significantly declining use of antimicrobials prescribed for resistant Gram-negative organisms, including carbapenems, as well as declining hospital readmission and mortality rates. Concurrently, the VHA reported decreasing rates of Clostridium difficile infection. CONCLUSIONS The VHA National Antimicrobial Stewardship Initiative includes continuing education, disease-specific guidelines, and development of example policies in addition to other highly utilized resources. While no specific ideal level of antimicrobial utilization has been established, the VHA has shown that improving antimicrobial usage in a large healthcare system may be achieved through national guidance and resources with local implementation of antimicrobial stewardship programs. Infect Control Hosp Epidemiol 2017;38:513-520.

Isolation and Identification of Phyllospheric Bacteria Possessing Antimicrobial Activity from Astragalus obtusifolius, Prosopis juliflora, Xanthium strumarium and Hippocrepis unisiliqousa

PubMed Central

Mazinani, Zohreh; Zamani, Marzieh

2017-01-01

Background: The widespread utilization of antimicrobial compounds has caused emergence of resistant microorganisms in the world. Hence, the research to probe the products with antimicrobial features has led to finding natural habitats and discovering new pharmaceutical products. Methods: In this study, an attempt was made to explore the niche of novel habitat to isolate pyllospheric bacteria from the above ground parts (stems and leaves) of Astragalus obtusifolius, Prosopis juliflora, Xanthium strumarium, and Hippocrepis unisiliqousa to evaluate their antimicrobial features. The inhibitory effects of these strains on the growth of two fungi (Aspergillus niger, Aspergillus fumigatus), two yeasts (Saccharomyces cerevisiae, Candida albicans) and six bacteria (Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Bacillus subtilis, Salmonella typhi, Streptococcus pyogenes) were tested. Results: In total, 113 bacterial strains were isolated. Twenty five bacterial strains (B-1 to B-25) indicated promising antimicrobial (antibacterial and antifungal) activities against aforementioned pathogens. The identification of the bacterial strains was ascertained by morphological, physiological, biochemical tests and two strains with the strongest antimicrobial activities were further characterized based on 16s rRNA sequencing. These two strains were identified as Bacillus amyloliquefaciens. Conclusion: Our results provide evidence that phyllospheric microorganisms are capable of producing some compounds with antimicrobial properties. PMID:28090278

Isolation of antimicrobial producing Actinobacteria from soil samples.

PubMed

Elbendary, Afaf Ahmed; Hessain, Ashgan Mohamed; El-Hariri, Mahmoud Darderi; Seida, Ahmed Adel; Moussa, Ihab Mohamed; Mubarak, Ayman Salem; Kabli, Saleh A; Hemeg, Hassan A; El Jakee, Jakeen Kamal

2018-01-01

Emergence of multidrug resistant bacteria has made the search for novel bioactive compounds from natural and unexplored habitats a necessity. Actinobacteria have important bioactive substances. The present study investigated antimicrobial activity of Actinobacteria isolated from soil samples of Egypt. One hundred samples were collected from agricultural farming soil of different governorates. Twelve isolates have produced activity against the tested microorganisms ( S. aureus , Bacillus cereus , E. coli , K. pneumoniae , P. aeruginosa , S. Typhi, C. albicans , A. niger and A. flavus ). By VITEK 2 system version: 07.01 the 12 isolates were identified as Kocuria kristinae , Kocuria rosea , Streptomyces griseus , Streptomyces flaveolus and Actinobacteria . Using ethyl acetate extraction method the isolates culture's supernatants were tested by diffusion method against indicator microorganisms. These results indicate that Actinobacteria isolated from Egypt farms could be sources of antimicrobial bioactive substances.

Evaluation of wound healing property of Caesalpinia mimosoides Lam.

PubMed

Bhat, Pradeep Bhaskar; Hegde, Shruti; Upadhya, Vinayak; Hegde, Ganesh R; Habbu, Prasanna V; Mulgund, Gangadhar S

2016-12-04

Caesalpinia mimosoides Lam. is one of the important traditional folk medicinal plants in the treatment of skin diseases and wounds used by healers of Uttara Kannada district of Karnataka state (India). However scientific validation of documented traditional knowledge related to medicinal plants is an important path in current scenario to fulfill the increasing demand of herbal medicine. The study was carried out to evaluate the claimed uses of Caesalpinia mimosoides using antimicrobial, wound healing and antioxidant activities followed by detection of possible active bio-constituents. Extracts prepared by hot percolation method were subjected to preliminary phytochemical analysis followed by antimicrobial activity using MIC assay. In vivo wound healing activity was evaluated by circular excision and linear incision wound models. The extract with significant antimicrobial and wound healing activity was investigated for antioxidant capacity using DPPH, nitric oxide, antilipid peroxidation and total antioxidant activity methods. Total phenolic and flavonoid contents were also determined by Folin-Ciocalteu, Swain and Hillis methods. Possible bio-active constituents were identified by GC-MS technique. RP-UFLC-DAD analysis was carried out to quantify ethyl gallate and gallic acid in the plant extract. Preliminary phytochemical analysis showed positive results for ethanol and aqueous extracts for all the chemical constituents. The ethanol extract proved potent antimicrobial activity against both bacterial and fungal skin pathogens compared to other extracts. The efficacy of topical application of potent ethanol extract and traditionally used aqueous extracts was evidenced by the complete re-epithelization of the epidermal layer with increased percentage of wound contraction in a shorter period. However, aqueous extract failed to perform a consistent effect in the histopathological assessment. Ethanol extract showed effective scavenging activity against DPPH and nitric oxide free radicals with an expressive amount of phenolic and moderate concentration of flavonoid contents. Ethyl gallate and gallic acid were found to be the probable bio-active compounds evidenced by GCMS and RP-UFLC-DAD analysis. The study revealed the significant antimicrobial, wound healing and antioxidant activities of tender parts of C. mimosoides and proved the traditional folklore knowledge. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Antimicrobial Properties of Biofunctionalized Silver Nanoparticles on Clinical Isolates of Streptococcus mutans and Its Serotypes

PubMed Central

Martínez-Robles, Ángel Manuel; Loyola-Rodríguez, Juan Pablo; Zavala-Alonso, Norma Verónica; Martinez-Martinez, Rita Elizabeth; Ruiz, Facundo; Lara-Castro, René Homero; Donohué-Cornejo, Alejandro; Reyes-López, Simón Yobanny; Espinosa-Cristóbal, León Francisco

2016-01-01

(1) Background: Streptococcus mutans (S. mutans) is the principal pathogen involved in the formation of dental caries. Other systemic diseases have also been associated with specific S. mutans serotypes (c, e, f, and k). Silver nanoparticles (SNP) have been demonstrated to have good antibacterial effects against S. mutans; therefore, limited studies have evaluated the antimicrobial activity of biofunctionalized SNP on S. mutans serotypes. The purpose of this work was to prepare and characterize coated SNP using two different organic components and to evaluate the antimicrobial activity of SNP in clinical isolates of S. mutans strains and serotypes; (2) Methods: SNP with bovine serum albumin (BSA) or chitosan (CS) coatings were prepared and the physical, chemical and microbiological properties of SNP were evaluated; (3) Results: Both types of coated SNP showed antimicrobial activity against S. mutans bacteria and serotypes. Better inhibition was associated with smaller particles and BSA coatings; however, no significant differences were found between the different serotypes, indicating a similar sensitivity to the coated SNP; (4) Conclusion: This study concludes that BSA and CS coated SNP had good antimicrobial activity against S. mutans strains and the four serotypes, and this study suggest the widespread use of SNP as an antimicrobial agent for the inhibition of S. mutans bacteria. PMID:28335264

Antimicrobial Properties of Biofunctionalized Silver Nanoparticles on Clinical Isolates of Streptococcus mutans and Its Serotypes.

PubMed

Martínez-Robles, Ángel Manuel; Loyola-Rodríguez, Juan Pablo; Zavala-Alonso, Norma Verónica; Martinez-Martinez, Rita Elizabeth; Ruiz, Facundo; Lara-Castro, René Homero; Donohué-Cornejo, Alejandro; Reyes-López, Simón Yobanny; Espinosa-Cristóbal, León Francisco

2016-07-22

(1) Background: Streptococcus mutans ( S. mutans ) is the principal pathogen involved in the formation of dental caries. Other systemic diseases have also been associated with specific S. mutans serotypes ( c , e , f , and k ). Silver nanoparticles (SNP) have been demonstrated to have good antibacterial effects against S. mutans ; therefore, limited studies have evaluated the antimicrobial activity of biofunctionalized SNP on S. mutans serotypes. The purpose of this work was to prepare and characterize coated SNP using two different organic components and to evaluate the antimicrobial activity of SNP in clinical isolates of S. mutans strains and serotypes; (2) Methods: SNP with bovine serum albumin (BSA) or chitosan (CS) coatings were prepared and the physical, chemical and microbiological properties of SNP were evaluated; (3) Results: Both types of coated SNP showed antimicrobial activity against S. mutans bacteria and serotypes. Better inhibition was associated with smaller particles and BSA coatings; however, no significant differences were found between the different serotypes, indicating a similar sensitivity to the coated SNP; (4) Conclusion: This study concludes that BSA and CS coated SNP had good antimicrobial activity against S. mutans strains and the four serotypes, and this study suggest the widespread use of SNP as an antimicrobial agent for the inhibition of S. mutans bacteria.

Antimicrobial Activity and Modulatory Effect of Essential Oil from the Leaf of Rhaphiodon echinus (Nees & Mart) Schauer on Some Antimicrobial Drugs.

PubMed

Duarte, Antonia Eliene; de Menezes, Irwin Rose Alencar; Bezerra Morais Braga, Maria Flaviana; Leite, Nadghia Figueiredo; Barros, Luiz Marivando; Waczuk, Emily Pansera; Pessoa da Silva, Maria Arlene; Boligon, Aline; Teixeira Rocha, João Batista; Souza, Diogo Onofre; Kamdem, Jean Paul; Melo Coutinho, Henrique Douglas; Escobar Burger, Marilise

2016-06-08

Rhaphiodon echinus is a weed plant used in the Brazilian folk medicinal for the treatment of infectious diseases. In this study, the essential oil of R. echinus leaf was investigated for its antimicrobial properties. The chemical constituents of the essential oil were characterized by GC-MS. The antimicrobial properties were determined by studying by the microdilution method the effect of the oil alone, and in combination with antifungal or antibiotic drugs against the fungi Candida albicans, Candida krusei and Candida tropicalis and the microbes Escherichia coli, Staphylococcus aureus and Pseudomonas. In addition, the iron (II) chelation potential of the oil was determined. The results showed the presence of β-caryophyllene and bicyclogermacrene in major compounds, and revealed a low antifungal and antibacterial activity of the essential oil, but a strong modulatory effect on antimicrobial drugs when associated with the oil. The essential oil showed iron (II) chelation activity. The GC-MS characterization revealed the presence of monoterpenes and sesquiterpenes in the essential oil and metal chelation potential, which may be responsible in part for the modulatory effect of the oil. These findings suggest that essential oil of R. echinus is a natural product capable of enhancing the antibacterial and antifungal activity of antimicrobial drugs.

Antimicrobial action of an endophytic fungi from Sophor flavescens and structure identification of its active constituent

PubMed Central

Yu, Na; He, Lu; Liu, Na; Wang, Yong; Xu, Hongbo; Liu, Dandan

2014-01-01

Endophytic fungus BS002 was isolated and characterized from Sophora flavescens by plate method, which has broad antimicrobial activity. Isolation and trace of a new bioactive compound from the fungus’ culture extracts with the method of column chromatography and TLC biological autoradiography was conducted. Finally, it was identified as 6,7-(2′E) dibutenyl-5,8-dihydroxy-(Z)-cyclooct-2-ene-1,4-dione by nuclear magnetic resonance, infrared and liquid chromatography–mass spectrometry. The compound presented strong antifungal activities for example: Botryosphaeria berengriana f.sp. piricola, Physalospora piricola, Cladosporium cucumerinum Ell. Arthur., Fusarium oxysporum f.sp. cucumerinum, Fusarium moniliforme. The inhibition to Physalospora piricola was the strongest with an antibacterial diameter of 45 mm. This paper is the first report of the antimicrobial activity of endophytic fungi BS002 that was the secondary metabolites extracted from the seeds of Sophora flavescens. The results provide a broad foreground for biopharmaceuticals and biopesticide. PMID:26019517

Graph Theoretical Analysis, In Silico Modeling, Synthesis, Anti-Microbial and Anti-TB Evaluation of Novel Quinoxaline Derivatives.

PubMed

Saravanan, Govindaraj; Selvam, Theivendren Panneer; Alagarsamy, Veerachamy; Kunjiappan, Selvaraj; Joshi, Shrinivas D; Indhumathy, Murugan; Kumar, Pandurangan Dinesh

2018-05-01

We designed to synthesize a number of 2-(2-(substituted benzylidene) hydrazinyl)-N-(4-((3-(phenyl imino)-3,4-dihydro quinoxalin-2(1 H)-ylidene)amino) phenyl) acetamide S1-S13: with the hope to obtain more active and less toxic anti-microbial and anti-TB agents. A series of novel quinoxaline Schiff bases S1-S13: were synthesized from o-phenylenediamine and oxalic acid by a multistep synthesis. In present work, we are introducing graph theoretical analysis to identify drug target. In the connection of graph theoretical analysis, we utilised KEGG database and Cytoscape software. All the title compounds were evaluated for their in-vitro anti-microbial activity by using agar well diffusion method at three different concentration levels (50, 100 and 150 µg/ml). The MIC of the compounds was also determined by agar streak dilution method. The identified study report through graph theoretical analysis were highlights that the key virulence factor for pathogenic mycobacteria is a eukaryotic-like serine/threonine protein kinase, termed PknG. All compounds were found to display significant activity against entire tested bacteria and fungi. In addition the synthesized scaffolds were screened for their in vitro antituberculosis (anti-TB) activity against Mycobacterium tuberculosis (Mtb) strain H 37 Ra using standard drug Rifampicin. A number of analogs found markedly potent anti-microbial and anti-TB activity. The relationship between the functional group variation and the biological activity of the evaluated compounds were well discussed. The observed study report was showing that the compound S6: (4-nitro substitution) exhibited most potent effective anti-microbial and anti-TB activity out of various tested compounds. © Georg Thieme Verlag KG Stuttgart · New York.

In vitro investigation of antimicrobial activities of ethnomedicinal plants against dental caries pathogens.

PubMed

Besra, Mamta; Kumar, Vipin

2018-05-01

The study aimed to evaluate the antimicrobial activity of medicinal plant extracts against the bacterial pathogens prominent in dental caries. A total of 20 plant species (herbs, shrubs and trees) belonging to 18 genera and 15 families were documented for dental caries. Antimicrobial activity of solvent extracts and essential oil from plants were determined by zone of inhibition on the growth of Streptococcus mutans (MTCC 497) and Lactobacillus acidophilus (MTCC 10307) using the agar well diffusion method. The results of in vitro antimicrobial assay prove that methanol is more successful in the extraction of phytochemicals from plant samples than aqueous solvent, as methanol extracts show higher antimicrobial activity than aqueous extracts against both the test pathogens. Methanol extracts of Nigella sativa, Psidium guajava and Syzygium aromaticum were the most effective among all 20 plant samples and have potent inhibitory activity against both dental caries pathogens with minimum inhibitory concentration of 0.2 mg mL - 1 . N. sativa seed methanol extract was more effective with 22.3 mm zone of inhibition at 0.2 mg mL - 1 against S. mutans (MTCC 497), while L. acidophilus (MTCC 10307) was more sensitive to S. aromaticum bud methanol extract at 11.3 mm zone of inhibition at concentration 0.1 mg mL - 1 . Essential oil extracted from plants also possesses strong antimicrobial activity for both test pathogens, with a minimum inhibitory concentration range of 0.05-0.16 mg mL - 1 . Syzygium aromaticum bud essential oil at 0.05 mg mL - 1 was most active against S. mutans (MTCC 497). Plant extracts viewing antimicrobial activity with minimum inhibitory concentration show the efficacy of the plant products that could be considered as a good indicator of prospective plants for discovering new antimicrobial agents against dental caries pathogens. The findings of this study provide a lead to further polyherbal formulations for the treatment of dental caries malaise.

Analysis of Polyphenolic Compounds in Extracts from Leaves of Some Malus domestica Cultivars: Antiradical and Antimicrobial Analysis of These Extracts

PubMed Central

Sowa, Alina; Zgórka, Grażyna; Szykuła, Aleksandra; Franiczek, Roman; Żbikowska, Beata; Gamian, Andrzej

2016-01-01

In this study, methanol, ethyl acetate, water extracts, and precipitate were obtained from leaves of Malus domestica cultivars: Golden delicious, Jonagold, Elstar, Ligol, and Mutsu. Antiradical activity of these extracts was measured using the ABTS+∙ radical, and antimicrobial activity was measured with the disk-diffusion method. Phenolic compounds were measured with the colorimetric method and identified with high performance liquid chromatography (HPLC). The highest antiradical activity was observed for the Jonagold variety, and in particular strong activity was noted for ethyl acetate extracts. Antimicrobial activity was observed against strains of Staphylococcus aureus, Enterococcus faecalis, and the fungus Candida glabrata. Particularly susceptible to the extracts activity appeared to be Staphylococcus aureus, but the growth of Candida glabrata was inhibited in the presence of ethyl acetate extracts. With the HPLC method we identified a high amount of phloridzin (above 500 mg per g of ethyl acetate extracts), lower amounts of hyperoside, isoquercitrin, and quercitrin, and traces of p-hydroxybenzoic and chlorogenic acids. The contribution of phloridzin to antiradical activity of methanol and ethyl acetate extracts was very high (above 90%). In water extract the contribution of phloridzin was between 38.9 and 55.2%, chlorogenic acid 22.7 and 36.1%, and hyperoside 12.2 and 13.3%. PMID:28097143

Analysis of Polyphenolic Compounds in Extracts from Leaves of Some Malus domestica Cultivars: Antiradical and Antimicrobial Analysis of These Extracts.

PubMed

Sowa, Alina; Zgórka, Grażyna; Szykuła, Aleksandra; Franiczek, Roman; Żbikowska, Beata; Gamian, Andrzej; Sroka, Zbigniew

2016-01-01

In this study, methanol, ethyl acetate, water extracts, and precipitate were obtained from leaves of Malus domestica cultivars: Golden delicious, Jonagold, Elstar, Ligol, and Mutsu. Antiradical activity of these extracts was measured using the ABTS +∙ radical, and antimicrobial activity was measured with the disk-diffusion method. Phenolic compounds were measured with the colorimetric method and identified with high performance liquid chromatography (HPLC). The highest antiradical activity was observed for the Jonagold variety, and in particular strong activity was noted for ethyl acetate extracts. Antimicrobial activity was observed against strains of Staphylococcus aureus , Enterococcus faecalis , and the fungus Candida glabrata . Particularly susceptible to the extracts activity appeared to be Staphylococcus aureus , but the growth of Candida glabrata was inhibited in the presence of ethyl acetate extracts. With the HPLC method we identified a high amount of phloridzin (above 500 mg per g of ethyl acetate extracts), lower amounts of hyperoside, isoquercitrin, and quercitrin, and traces of p -hydroxybenzoic and chlorogenic acids. The contribution of phloridzin to antiradical activity of methanol and ethyl acetate extracts was very high (above 90%). In water extract the contribution of phloridzin was between 38.9 and 55.2%, chlorogenic acid 22.7 and 36.1%, and hyperoside 12.2 and 13.3%.

Development of a New Monomer for the Synthesis of Intrinsic Antimicrobial Polymers with Enhanced Material Properties.

PubMed

Brodkorb, Florian; Fischer, Björn; Kalbfleisch, Katrin; Robers, Oliver; Braun, Carina; Dohlen, Sophia; Kreyenschmidt, Judith; Lorenz, Reinhard; Kreyenschmidt, Martin

2015-08-24

The use of biocidal compounds in polymers is steadily increasing because it is one solution to the need for safety and hygiene. It is possible to incorporate an antimicrobial moiety to a polymer. These polymers are referred to as intrinsic antimicrobial. The biocidal action results from contact of the polymer to the microorganisms, with no release of active molecules. This is particularly important in critical fields like food technology, medicine and ventilation technology, where migration or leaching is crucial and undesirable. The isomers N-(1,1-dimethylethyl)-4-ethenyl-benzenamine and N-(1,1-dimethyl-ethyl)-3-ethenyl-benzenamine (TBAMS) are novel (Co-)Monomers for intrinsic anti-microbial polymers. The secondary amines were prepared and polymerized to the corresponding water insoluble polymer. The antimicrobial activity was analyzed by the test method JIS Z 2801:2000. Investigations revealed a high antimicrobial activity against Staphylococcus aureus and Escherichia coli with a reduction level of >4.5 log10 units. Furthermore, scanning electron microscopy (SEM) of E. coli. in contact with the polymer indicates a bactericidal action which is caused by disruption of the bacteria cell membranes, leading to lysis of the cells.

Synthesis, characterization and evaluation of 1,3,5-triazine aminobenzoic acid derivatives for their antimicrobial activity.

PubMed

Al-Zaydi, Khadijah M; Khalil, Hosam H; El-Faham, Ayman; Khattab, Sherine N

2017-05-10

Replacement of chloride ions in cyanuric chloride give several variants of 1,3,5-triazine derivatives which were investigated as biologically active small molecules. These compounds exhibit antimalarial, antimicrobial, anti-cancer and anti-viral activities, among other beneficial properties. On the other hand, treatment of bacterial infections remains a challenging therapeutic problem because of the emerging infectious diseases and the increasing number of multidrug-resistant microbial pathogens. As multidrug-resistant bacterial strains proliferate, the necessity for effective therapy has stimulated research into the design and synthesis of novel antimicrobial molecules. 1,3,5-Triazine 4-aminobenzoic acid derivatives were prepared by conventional method or by using microwave irradiation. Using microwave irradiation gave the desired products in less time, good yield and higher purity. Esterification of the 4-aminobenzoic acid moiety afforded methyl ester analogues. The s-triazine derivatives and their methyl ester analogues were fully characterized by FT-IR, NMR ( 1 H-NMR and 13 C-NMR), mass spectra and elemental analysis. All the synthesized compounds were evaluated for their antimicrobial activity. Some tested compounds showed promising activity against Staphylococcus aureus and Escherichia coli. Three series of mono-, di- and trisubstituted s-triazine derivatives and their methyl ester analogues were synthesized and fully characterized. All the synthesized compounds were evaluated for their antimicrobial activity. Compounds (10), (16), (25) and (30) have antimicrobial activity against S. aureus comparable to that of ampicillin, while the activity of compound (13) is about 50% of that of ampicillin. Compounds (13) and (14) have antimicrobial activity against E. coli comparable to that of ampicillin, while the activity of compounds (9-12) and (15) is about 50% of that of ampicillin. Furthermore, minimum inhibitory concentrations values for clinical isolates of compounds (10), (13), (14), (16), (25) and (30) were measured. Compounds (10) and (13) were more active against MRSA and E. coli than ampicillin. Invitro cytotoxicity results revealed that compounds (10) and (13) were nontoxic up to 250 µg/mL (with SI = 10) and 125 µg/mL (with SI = 5), respectively. Graphical abstract Three series of mono-, di- and trisubstituted s-triazine derivatives and their methyl ester analogues were synthesized and evaluated for their antimicrobial activity. Several compounds have antimicrobial activity against S. aureus and E. coli comparable to that of ampicillin.

Antimicrobial agents from selected medicinal plants in Libya.

PubMed

Muhaisen, Hasan M H; Ab-Mous, Miftah Mailoud; Ddeeb, Fadel A; Rtemi, Aboclaid Ali; Taba, Omer M; Parveen, Mehtab

2016-03-01

To test the in vitro antimicrobial efficacy of water and methanol extracts of 23 plant species that are commonly used in Libyan folk medicine. The antimicrobial activity was determined using the well-diffusion method. Four test microorganisms were used namely, Escherichia coli, Salmonella species, Staphylococcus aureus and Bacillus subtilis. The minimum inhibitory concentration (MIC) was determined for the high biologically active crude plant extracts. Among 23 medicinal plants used in the study, only 5 methanolic extracts [Rosmarinus offcinalis L., Carduus marianium L., Lantana camara L., Rhus tripartite (ueria) Grande, and Thymus capitatus (L.) Hoffm (link)] showed the highest antimicrobial activity against Staphylococcus aureus, Bacillus subtilis and Salmonella species, while 22 methanolic and aqueous extracts showed moderate to weak antimicrobial activity on all tested organisms. However 19 of the extracts showed no activity at all against Gram-ve and Gram +ve microorganisms. MIC was found to be 1.25 mg/mL (Thymus capitatus), 3 mg/mL (Rhus tripartite), 4 mg/mL (Carduus marianium), 5 mg/mL (Rosamarinus officinalis) and 5 mg/mL (Lantana camara), respectively. The present results revealed that, crude methanolic extracts of the investigated Libyan folk medicinal plants exhibited mild to high in vitro antibacterial activities against Gram-positive and Gram-negative microorganisms.

Characterizing a novel strain of Bacillus amyloliquefaciens BAC03 for potential biological control application

USDA-ARS?s Scientific Manuscript database

Aims: Identify and characterize a bacterial strain from suppressive soil, BAC03, evaluate its antimicrobial activity against Streptomyces scabies and other microorganisms, and characterize an antimicrobial substance produced by this strain. Methods and Results: Bacterial strain BAC03 (isolated from ...

Active edible coating and γ-irradiation as cold combined treatments to assure the safety of broccoli florets (Brassica oleracea L.).

PubMed

Ben-Fadhel, Yosra; Saltaji, Sabrina; Khlifi, Mohamed Ali; Salmieri, Stephane; Dang Vu, Khanh; Lacroix, Monique

2017-01-16

The antimicrobial activity of essential oils (EOs), organic acid (OA) salts and natamycin, a natural antifungal produced during fermentation by the bacterium Streptomyces natalensis, was assessed against four pathogens (Escherichia coli O157:H7, Listeria monocytogenes, Salmonella Typhimurium and Aspergillus niger). The Minimum Inhibitory Concentration (MIC) of each antimicrobial (AM) was assessed to determine their efficiency on tested microbial species in order to select the most efficient. Then, the interactions between different antimicrobial compounds showing the lowest MIC were determined by the checkerboard method. The most effective antimicrobial formulation showing synergistic or additive effects was then encapsulated in an alginate matrix to protect the antimicrobial efficiency during storage. The effectiveness of the formulation was then evaluated in situ using broccoli as a food model. A combined treatment of active coating and γ-irradiation (0.4 and 0.8kGy) was also done in order to evaluate the possible synergistic effect between treatments. The results of this study allowed the selection of 4 EOs, one OA salt and the natamycin as an antifungal agent exhibiting lower MIC values. The interactive antimicrobial effects between them showed that an antimicrobial formulation composed of 300ppm of lemongrass EO, 5000ppm of sodium diacetate and 80ppm of natamycin resulted in an additive effect against A. niger, E. coli and S. Typhimurium and showing synergistic effect against L. monocytogenes. Finally, in situ analyses showed a synergistic antimicrobial activity between active coating and γ-irradiation and allowed the extension of the shelf-life of ready-to-eat (RTE) broccoli during storage at 4°C. Copyright © 2016 Elsevier B.V. All rights reserved.

Bioassay-guided isolation and evaluation of antimicrobial compounds from Ixora megalophylla against some oral pathogens.

PubMed

Panyo, J; Matsunami, K; Panichayupakaranant, P

2016-09-01

Context Ixora megalophylla Chamch. (Rubiaceae) is a new plant species recently found in southern Thailand. Ethyl acetate extracts of its leaves and stems showed antimicrobial activities. Objectives To isolate and identify the antimicrobial compounds from I. megalophylla leaves and stems. Materials and methods The dried leaves (1.7 kg) and stems (3.5 kg) were consecutively extracted with petroleum ether (5 L × 4), ethyl acetate (5 L × 3) and ethanol (5 L × 4) under reflux conditions. The ethyl acetate extract was subjected to an antimicrobial assay guided isolation with Candida albicans and Streptococcus mutans. Compounds 1-10 were identified by (1)H NMR, (13)C NMR and EI-MS. Minimal lethal concentration (MLC) against C. albicans and Streptococcus spp. was determined using a broth microdilution method for 48 and 24 h, respectively. Results and discussion On the basis of the antimicrobial assay guided isolation, 10 known compounds, including vanillic acid (1), syringic acid (2), 4-hydroxy benzaldehyde (3), scopoletin (4), loliolide (5), syringaldehyde (6), sinapaldehyde (7), coniferaldehyde (8), syringaresinol (9) and 2,2'-dithiodipyridine (10), were identified. Compounds 1-5 were purified from the ethyl acetate extract of the leaves, while 6-9 and 10 were from the ethyl acetate and ethanol extracts of the stems, respectively. Among these isolates, 10 showed the strongest antibacterial activities against S. mutans and Streptococcus mitis, with minimum inhibitory concentrations (MICs) of 2-4 μg/mL, and MLC of 4 μg/mL, as well as having a weak antifungal activity against C. albicans (MIC of 125 μg/mL). This is the first report of the antimicrobial activities of 10.

Bacteriocin from Bacillus subtilis as a novel drug against diabetic foot ulcer bacterial pathogens.

PubMed

Joseph, Baby; Dhas, Berlina; Hena, Vimalin; Raj, Justin

2013-12-01

To isolate and identify Bacillus subtilis (B. subtilis) from soil and to characterize and partially purify the bacteriocin. To evaluate the antimicrobial activity against four diabetic foot ulcer bacterial pathogens. Genotypic identification was done based on Bergey's manual of systemic bacteriology. Antimicrobial susceptibility test was done by Kirby-Bauer disc diffusion method. Colonies were identified by colony morphology and biochemical characterization and also compared with MTCC 121 strain. Further identification was done by 16S rRNA sequencing. Inhibitory activities of partially purified bacteriocin on all the DFU isolates were done by agar well diffusion method. The strain was identified to produce bacteriocin by stab overlay assay. Bacteriocin was extracted by organic solvent extraction using chloroform, further purified by HPLC and physical, and chemical characterization was performed. The four isolates showed high level of resistance to amoxyclav and sensitivity to ciprofloxacin. HPLC purification revealed that the extracts are bacteriocin. The phylogenetic tree analysis results showed that the isolate was 99% related to B. subtilis BSF01. The results reveled activity to all the four isolates and high level of activity was seen in case of Klebsiella sp. Partially purified bacteriocin was found to have antimicrobial activity against the four diabetic foot ulcer bacterial pathogens, which can thus be applied as a better drug molecule on further studies. The strain B. subtilis are found to be safe for use and these antimicrobial peptides can be used as an antimicrobial in humans to treat DFU bacterial pathogens. Copyright © 2013 Asian Pacific Tropical Biomedical Magazine. Published by Elsevier B.V. All rights reserved.

Assessment of antinociceptive, antipyretic and antimicrobial activity of Piper cubeba L. essential oil in animal models.

PubMed

Mothana, Ramzi; Alsaid, Mansour; Khaled, Jamal M; Alharbi, Naiyf S; Alatar, Abdulrahman; Raish, Mohammad; Al-Yahya, Mohammed; Rafatullah, Syed; Parvez, Mohammad Khalid; Ahamad, Syed Rizwan

2016-03-01

This study was designed to investigate the possible antiniciceptive, antipyretic and antimicrobial activities of the essential oil obtained from the fruits of Piper Cubeba (L.). To assess the antinociceptive and antipyretic activities, three doses (150, 300 and 600 mg/kg, i.p.) were tested in acetic acid-induced abdominal writhing, tail flick reaction and hot-plate and Brewer's yeast-induced hyperpyrexia test models in animals. Moreover, the antimicrobial activity was examined using agar diffusion method and broth micro-dilution assay for minimum inhibitory concentrations (MIC). The Piper Cubeba essential oil (PCEO) showed a marked antinociception (17, 30 and 54%) and an increase in reaction time in mice in the flick tailed and hot-plate tests. The brewer's yeast induced hyperpyrexia was decreased in a dose dependent manner. PCEO also exhibited a strong antimicrobial potential. These findings confirm the traditional analgesic indications of P. cubeba oil and provide persuasive evidence and support its use in Arab traditional medicine.

Antimicrobial and antioxidant effect of methanolic Crinum jagus bulb extract in wound healing

PubMed Central

Udegbunam, Sunday Ositadimma; Udegbunam, Rita Ijeoma; Nnaji, Theophilus Okafor; Anyanwu, Madubuike Umunna; Kene, Raphel Okoli Chukwujekwu; Anika, Silavanus Maduka

2015-01-01

Aim: The aim of this study was to evaluate the antimicrobial and antioxidant effects of Crinum jagus (J. Thomps.) Dandy methanolic bulb extract in wound healing. Materials and Methods: Phytochemical screening revealed the presence of alkaloids, glycosides, tannins, and saponins in the extract. In vitro antimicrobial activity of the extract was determined by agar well diffusion method. In vivo antimicrobial activity of the extract was determined by microbial assay of excision wound in rats contaminated with Staphylococcus aureus, Bacillus subtilis, Pseudomonas areuginosa, and Candida albicans and treated with 300 mg/kg body weight (bw) of 10 and 5% methanolic C. jagus bulb extract ointment (MCJBEO), respectively. Enzymatic antioxidant effect of the extract was determined in vivo by assaying superoxide dismutase (SOD) and catalase (CAT) activity, and malondialdehyde (MDA) level in excision wound biopsies of rats treated with 10 and 5% MCJBEO, respectively, following standard methods. Non-enzymatic antioxidant effect of the extract was determined in vitro using diphenylpicrylhydrazyl (DPPH) method following standard procedure. Results: The extract exhibited in vitro antimicrobial effect in a concentration-dependent manner with one hundred (100) mg/ml concentration of the extract having the highest inhibitory zone diameter for B. subtilis (25 mm), S. aureus (21 mm), and C. albicans (14 mm) followed by the 50, 25 and 12.5 mg/ml concentrations, respectively. B. subtilis, S. aureus, and C. albicans were not isolated from wounds of animals treated with both extract concentrations 10% and 5% MCJBEO, and reference drug (framycetin sulfate/clotrimazole). Activities of the enzymatic antioxidants SOD and CAT in wound biopsies treated with 10% MCJBEO were significantly (P < 0.05) higher when compared with those treated with 5% MCJBEO. Significantly (P < 0.05) decreased MDA level of wound biopsies from extract-treated rats was observed. The extract exhibited non-enzymatic antioxidant (DPPH) effect in a concentration-dependent manner. Conclusion: This study has shown that an anti-microbial and antioxidant effects could possibly be part of mechanism by which C. jagus bulb extract promote wound healing process. PMID:26401415

Toxicity tests, antioxidant activity, and antimicrobial activity of chitosan

NASA Astrophysics Data System (ADS)

Kurniasih, M.; Purwati; Dewi, R. S.

2018-04-01

Chitosan is a naturally occurring cationic biopolymer, obtained by alkaline deacetylation of chitin. This research aims to investigate the toxicity, antioxidant activity and antibacterial activity of chitosan from shrimp chitin. In this study, chitin extracted from shrimp waste material. Chitin is then deacetylation with 60% NaOH so that chitosan produced. Degrees of deacetylation, molecular weight, toxicity test, antioxidant activity and antimicrobial activity of chitosan then evaluated. Toxicity test using Brine Shrimp Lethality Test. The antioxidant analysis was performed using DPPH method (2, 2-diphenyl-1-picrylhydrazyl) and FTC method (ferric thiocyanate) in which the radical formed will reduce Ferro to Ferri resulting in a complex with thiocyanate. To determine the antibacterial activity of Staphylococcus aureus, antifungal in Candida albicans and Aspergillus niger by measuring antimicrobial effects and minimum inhibitory concentrations (MIC). Based on the result of research, the value of degrees of deacetylation, molecular weight, and LC50 values of chitosan synthesis was 94,32, 1052.93 g/mol and 1364.41 ppm, respectively. In general, the antioxidative activities increased as the concentration of chitosan increased. MIC value of chitosan against S. aureus, C. albicans, and A. niger was 10 ppm, 15.6 ppm, and 5 ppm, respectively.

Pharmacological and phytochemical screening of Palestinian traditional medicinal plants Erodium laciniatum and Lactuca orientalis.

PubMed

Jaradat, Nidal; AlMasri, Motasem; Zaid, Abdel Naser; Othman, Dua'a Ghazi

2017-09-01

Various epidemiological studies showed that herbal remedies containing polyphenols may protect against various diseases such as cancers, vascular diseases and inflammatory pathologies. Currently, such groups of bioactive compounds have become a subject of many antimicrobials and antioxidant investigations. Accordingly, the current study aimed to conduct biological and phytochemical screening for two Palestinian traditional medicinal plants, Erodium laciniatum and Lactuca orientalis. Current plants phytoconstituents and their antioxidant activities were evaluated by using standard phytochemical methods; meanwhile, antimicrobial activities were estimated by using several types of American Type Culture Collection and multidrug resistant clinical isolates by using agar diffusion well-variant, agar diffusion disc-variant and broth microdilution methods. Phytochemical screenings showed that L. orientalis and E. laciniatum contain mixtures of secondary and primary metabolites Moreover, total flavonoid, tannins and phenols content in E. laciniatum extract were higher than the L. orientalis extracts with almost the same antioxidant potentials. Additionally, both plants organic and aqueous extracts showed various potentials of antimicrobial activity Conclusions: Overall, the studied species have a mixture of phytochemicals, flavonoids, phenols and tannins also have antioxidant and antimicrobial activities which approved their folk uses in treatments of infectious and Alzheimer diseases and simultaneously can be used as therapeutic agents in the pharmaceutical industries.

In-vitro evidence for efficacy of antimicrobial mouthrinses

PubMed Central

Pan, Pauline C.; Harper, Scott; Ricci-Nittel, Danette; Lux, Renate; Shi, Wenyuan

2010-01-01

SUMMARY Objectives The objective of this study was to compare the antimicrobial activity of commercially available antiseptic mouthrinses against saliva-derived plaque biofilms in static and flow-through biofilm systems in vitro. Methods Nine mouthrinses were tested in a recirculating flow-through biofilm model (RFTB) with viability assessment by ATP bioluminescence. In addition, five mouthrinses were evaluated in a batch chamber slide biofilm (BCSB) model, using live- dead staining and confocal laser scanning microscopy. Results In the RFTB model, essential oil (EO) and chlorhexidine (CHX)-containing rinses showed equivalent antimicrobial activity and were more effective than a range of cetyl pyridinium chloride (CPC1) formulations. In the BCSB model, twice-daily mouthrinse exposure demonstrated that the EO rinse was significantly more effective than rinses containing amine and stannous fluorides, a combination of CPC/CHX and CPC2. EO showed biofilm kill comparable to the CHX rinse. Conclusions The present studies have shown that mouthrinses vary significantly in their capability to kill plaque biofilm bacteria in BCSB and RFTB models. The EO mouthrinse demonstrated superior antiplaque biofilm activity to AFSF, CPC/CHX, and CPC rinses and comparable activity to CHX. The methods tested may be of value for the in-vitro screening of antiseptic rinses with different modes of antimicrobial action. PMID:20621239

Phytochemical screening, antioxidants and antimicrobial potential of Lantana camara in different solvents

PubMed Central

Naz, Rabia; Bano, Asghari

2013-01-01

Objective To evaluate the antioxidant activity, hydrogen peroxide radicals scavenging activity, reducing power, the total phenolic and flavonoids contents, and antimicrobial and antifungal activities of methanol, ethanol and water extracts of leaves of Lantana camara (L. camara). Methods Methanol, ethanol and water extracts were evaluated against four Gram positive and Gram negative bacterial isolates (Staphylococcus aureus, Pseudomonas aeruginosa, Klebsiella pneumoniae, Bacillus subtilis) and two fungal strains (Aspergillus fumigatus and Aspergillus flavus). Methanol extract at different concentrations was tested for antioxidant potential and phytochemicals were determined by using spectrophotometric method. Results The total phenolic content was (40.859±0.017) mg gallic acid/g in the leaves of L. camara, while the total flavonoids was (53.112±0.199) mg/g dry weight. Methanol leaf extract of L. camara showed maximum antibacterial activity against Staphylococcus aureus and Pseudomonas aeruginosa and was also effective against other bacterial strains as compared to ethanol and aqueous extracts of leaves. The methanol leaf extract of L. camara exhibited significant inhibition (71%) and (66%) against Aspergillus fumigatus and Aspergillus flavus respectively. Conclusions The methanol extract of the L. camara leaves is effective against selected bacterial and fungal strains. Its phytochemical contents have broad antimicrobial properties and the plant might be a novel source of antimicrobial drug.

Quantitative Assessment of Antimicrobial Activity of PLGA Films Loaded with 4-Hexylresorcinol

PubMed Central

Kemme, Michael; Heinzel-Wieland, Regina

2018-01-01

Profound screening and evaluation methods for biocide-releasing polymer films are crucial for predicting applicability and therapeutic outcome of these drug delivery systems. For this purpose, we developed an agar overlay assay embedding biopolymer composite films in a seeded microbial lawn. By combining this approach with model-dependent analysis for agar diffusion, antimicrobial potency of the entrapped drug can be calculated in terms of minimum inhibitory concentrations (MICs). Thus, the topical antiseptic 4-hexylresorcinol (4-HR) was incorporated into poly(lactic-co-glycolic acid) (PLGA) films at different loadings up to 3.7 mg/cm2 surface area through a solvent casting technique. The antimicrobial activity of 4-HR released from these composite films was assessed against a panel of Gram-negative and Gram–positive bacteria, yeasts and filamentous fungi by the proposed assay. All the microbial strains tested were susceptible to PLGA-4-HR films with MIC values down to 0.4% (w/w). The presented approach serves as a reliable method in screening and quantifying the antimicrobial activity of polymer composite films. Moreover, 4-HR-loaded PLGA films are a promising biomaterial that may find future application in the biomedical and packaging sector. PMID:29324696

Chemical composition, antimicrobial and antioxidant potential of the essential oil of Guarea kunthiana A. Juss.

PubMed

Pandini, J A; Pinto, F G S; Scur, M C; Santana, C B; Costa, W F; Temponi, L G

2018-02-01

The essential oils are extracted from plant compounds and can present activities antimicrobial and antioxidant properties. The goals of the present study were: (a) to determine the chemical composition of the essential oil of Guarea kunthiana A. Juss using the method of gas chromatography coupled to mass spectrometry (GC-MS); (b) to evaluate the antimicrobial potential of this oil using the broth microdilution method against different microorganisms: five Gram-negative bacteria, four Gram-positive bacteria and a yeast and (c) to determine the antioxidant activity of the oil using the DPPH (2,2-diphenyl-1-picrylhydrazyl) free radical assay. The GC-MS analyses allowed identifying 13 constituents, representing 96.52% of the essencial oil composition. The main compounds identified were α-zingiberene (34.48%), β-sesquiphellandrene (22.90%), and α-curcumene (16.17%). With respect to the antimicrobial activity, the essential oil was effective against all the microorganisms tested, except for the bacteria E. coli and K. pneumoniae, which were resistant to the action of the oil. From a general point of view, Gram-positive bacteria were more susceptible to the action of the essential oil than Gram-negative bacteria. The essential oil exhibited antioxidant potential.

In vitro antimicrobial activity of extracts and isolated compound from Dalbergia stipulacea Roxb. leaves

NASA Astrophysics Data System (ADS)

Kumar, Arvind; Bhat, Tahir Ahmad; Singh, Rattan Deep

2017-07-01

The study was designed to examine the in vitro antimicrobial efficacy of extracts and isolated compound of Dalbergia stipulacea. Combined extracts (chloroform and methanol) of plant leaves fractionated with n-butanol loaded with column afforded a flavonoid glycoside compound identified as luteolin 4'-rutinoside. Different extracts and isolated compound exhibited pronounced antibacterial and antifungal varied activities against four bacteria (Clostridium acetobutylinium, Bacillus subtilis, Streptococcus mutans, and Pseudomonas sp.) and one fungus (Candida albicans) susceptibility were determined using disc diffusion method. The minimum inhibitory concentration (MIC) of extracts and isolated compounds was determined by broth dilution method. The maximum activity was shown by chloroform extract against C. albicans with a zone of inhibition of 17 mm and minimum activity was displayed by methanolic extract against Pseudomonas sp. with 5 mm. However, isolated compound has shown maximum activity against Pseudomonas sp. with 15 mm. The MIC values higher in methanol extract against Pseudomonas sp. and isolated compound shows good against Pseudomonas sp. and B. subtilis. Our findings indicate that plant could be used as a good antimicrobial agent in food, pharmaceutical and bio-pesticide industries.

Antimicrobial activity of spherical silver nanoparticles: evidence for induction of a prolonged bacterial lag phase

USDA-ARS?s Scientific Manuscript database

Background: Recently, there has been a great deal of interest surrounding the discovery that Ag[0] nanoparticles (Np) are more effective antimicrobial agents in terms of the minimum effective concentration than their Ag[+] counterparts. Methods: Both solid and liquid phase experiments were perform...

Antimicrobial activity of filamentous fungi isolated from highly antibiotic-contaminated river sediment

PubMed Central

Svahn, K. Stefan; Göransson, Ulf; El-Seedi, Hesham; Bohlin, Lars; Larsson, D.G. Joakim; Olsen, Björn; Chryssanthou, Erja

2012-01-01

Background Filamentous fungi are well known for their production of substances with antimicrobial activities, several of which have formed the basis for the development of new clinically important antimicrobial agents. Recently, environments polluted with extraordinarily high levels of antibiotics have been documented, leading to strong selection pressure on local sentinel bacterial communities. In such microbial ecosystems, where multidrug-resistant bacteria are likely to thrive, it is possible that certain fungal antibiotics have become less efficient, thus encouraging alternative strategies for fungi to compete with bacteria. Methods In this study, sediment of a highly antibiotic-contaminated Indian river was sampled in order to investigate the presence of cultivable filamentous fungi and their ability to produce substances with antimicrobial activity. Results Sixty one strains of filamentous fungi, predominantly various Aspergillus spp. were identified. The majority of the Aspergillus strains displayed antimicrobial activity against methicillin-resistant Staphylococcus aureus, extended-spectrum beta-lactamase-producing Escherichia coli, vancomycin-resistant Enterococcus faecalis and Candida albicans. Bioassay-guided isolation of the secondary metabolites of A. fumigatus led to the identification of gliotoxin. Conclusion This study demonstrated proof of principle of using bioassay-guided isolation for finding bioactive molecules. PMID:22957125

Antimicrobial activity and mechanism of PDC213, an endogenous peptide from human milk.

PubMed

Sun, Yazhou; Zhou, Yahui; Liu, Xiao; Zhang, Fan; Yan, Linping; Chen, Ling; Wang, Xing; Ruan, Hongjie; Ji, Chenbo; Cui, Xianwei; Wang, Jiaqin

2017-02-26

Human milk has always been considered an ideal source of elemental nutrients to both preterm and full term infants in order to optimally develop the infant's tissues and organs. Recently, hundreds of endogenous milk peptides were identified in human milk. These peptides exhibited angiotensin-converting enzyme inhibition, immunomodulation, or antimicrobial activity. Here, we report the antimicrobial activity and mechanism of a novel type of human antimicrobial peptide (AMP), termed PDC213 (peptide derived from β-Casein 213-226 aa). PDC213 is an endogenous peptide and is present at higher levels in preterm milk than in full term milk. The inhibitory concentration curve and disk diffusion tests showed that PDC213 had obvious antimicrobial against S. aureus and Y. enterocolitica, the common nosocomial pathogens in neonatal intensive care units (NICUs). Fluorescent dye methods, electron microscopy experiments and DNA-binding activity assays further indicated that PDC213 can permeabilize bacterial membranes and cell walls rather than bind intracellular DNA to kill bacteria. Together, our results suggest that PDC213 is a novel type of AMP that warrants further investigation. Copyright © 2017 Elsevier Inc. All rights reserved.

Antimicrobial activity and mechanism of PDC213, an endogenous peptide from human milk

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sun, Yazhou; Nanjing Maternal and Child Health Medical Institute, Nanjing Maternal and Child Health Hospital, Obstetrics and Gynecology Hospital Affiliated to Nanjing Medical University, Nanjing; Zhou, Yahui

Human milk has always been considered an ideal source of elemental nutrients to both preterm and full term infants in order to optimally develop the infant's tissues and organs. Recently, hundreds of endogenous milk peptides were identified in human milk. These peptides exhibited angiotensin-converting enzyme inhibition, immunomodulation, or antimicrobial activity. Here, we report the antimicrobial activity and mechanism of a novel type of human antimicrobial peptide (AMP), termed PDC213 (peptide derived from β-Casein 213-226 aa). PDC213 is an endogenous peptide and is present at higher levels in preterm milk than in full term milk. The inhibitory concentration curve and diskmore » diffusion tests showed that PDC213 had obvious antimicrobial against S. aureus and Y. enterocolitica, the common nosocomial pathogens in neonatal intensive care units (NICUs). Fluorescent dye methods, electron microscopy experiments and DNA-binding activity assays further indicated that PDC213 can permeabilize bacterial membranes and cell walls rather than bind intracellular DNA to kill bacteria. Together, our results suggest that PDC213 is a novel type of AMP that warrants further investigation. - Highlights: • PDC213 is an endogenous peptide presenting higher levels in preterm milk. • PDC213 showed obvious antimicrobial against S. aereus and Y. enterocolitica. • PDC213 can permeabilize bacterial membranes and cell walls to kill bacterias. • PDC213 is a novel type of antimicrobial peptides worthy further investigation.« less

Gas Chromatography, GC/Mass Analysis and Bioactivity of Essential Oil from Aerial Parts of Ferulago trifida: Antimicrobial, Antioxidant, AChE Inhibitory, General Toxicity, MTT Assay and Larvicidal Activities

PubMed Central

Tavakoli, Saeed; Vatandoost, Hassan; Zeidabadinezhad, Reza; Hajiaghaee, Reza; Hadjiakhoondi, Abbas; Abai, Mohammad Reza; Yassa, Narguess

2017-01-01

Background: We aimed to investigate different biological properties of aerial parts essential oil of Ferulago trifida Boiss and larvicidal activity of its volatile oils from all parts of plant. Methods: Essential oil was prepared by steam distillation and analyzed by Gas chromatography and GC/Mass. Antioxidant, antimicrobial, cytotoxic effects and AChE inhibitory of the oil were investigated using DPPH, disk diffusion method, MTT assay and Ellman methods. Larvicidal activity of F. trifida essential oil against malaria vector Anopheles stephensi was carried out according to the method described by WHO. Results: In GC and GC/MS analysis, 58 compounds were identified in the aerial parts essential oil, of which E-verbenol (9.66%), isobutyl acetate (25.73%) and E-β-caryophyllene (8.68%) were main compounds. The oil showed (IC50= 111.2μg/ml) in DPPH and IC50= 21.5 mg/ml in the investigation of AChE inhibitory. Furthermore, the oil demonstrated toxicity with (LD50= 1.1μg/ml) in brine shrimp lethality test and with (IC50= 22.0, 25.0 and 42.55 μg/ml) on three cancerous cell lines (MCF-7, A-549 and HT-29) respectively. LC50 of stem, root, aerial parts, fruits, and flowers essential oils against larvae of An. stephensi were equal with 10.46, 22.27, 20.50, 31.93 and 79.87ppm respectively. In antimicrobial activities, essential oil was effective on all specimens except Escherichia coli, Aspergillus niger and Candida albicans. Conclusion: The essential oil showed moderate antioxidant activity, strong antimicrobial properties and good toxic effect in brine shrimp test and MTT assay on three cancerous cell lines. PMID:29322058

Antimicrobial Activity and Brine Shrimp Lethality Bioassay of the Leaves Extract of Dillenia indica Linn.

PubMed

Apu, As; Muhit, Ma; Tareq, Sm; Pathan, Ah; Jamaluddin, Atm; Ahmed, M

2010-01-01

The crude methanolic extract of Dillenia indica Linn. (Dilleniaceae) leaves has been investigated for the evaluation of antimicrobial and cytotoxic activities. Organic solvent (n-hexane, carbon tetrachloride and chloroform) fractions of methanolic extract and methanolic fraction (aqueous) were screened for their antimicrobial activity by disc diffusion method. Besides, the fractions were screened for cytotoxic activity using brine shrimp (Artemia salina) lethality bioassay. Among the four fractions tested, n-hexane, carbon tetrachloride, and chloroform fractions showed moderate antibacterial and antifungal activity compared to standard antibiotic, kanamycin. The average zone of inhibition was ranged from 6 to 8 mm at a concentration of 400 µg/disc. But the aqueous fraction was found to be insensitive to microbial growth. Compared to vincristine sulfate (with LC(50) of 0.52 µg/ ml), n-hexane and chloroform fractions demonstrated a significant cytotoxic activity (having LC(50) of 1.94 µg/ml and 2.13 µg/ml, respectively). The LC(50) values of the carbon tetrachloride and aqueous fraction were 4.46 µg/ml and 5.13 µg/ ml, respectively. The study confirms the moderate antimicrobial and potent cytotoxic activities of Dillenia indica leaves extract and therefore demands the isolation of active principles and thorough bioassay.

Diversity and antimicrobial activity of endophytic fungi associated with the alpine plant Saussurea involucrata.

PubMed

Lv, Ya-li; Zhang, Fu-sheng; Chen, Juan; Cui, Jin-long; Xing, Yong-mei; Li, Xiang-dong; Guo, Shun-xing

2010-01-01

Endophytic fungi are rich in species diversity and may play an important role in the fitness of their host plants. This study investigated the diversity and antimicrobial potential of endophytic fungi obtained from Saussurea involucrata KAR. et KIR. A total of 49 endophytic fungi were isolated from S. involucrata and identified using morphological and molecular techniques. Extracts of fermentation broth from the 49 fungi were tested for antimicrobial activity against pathogenic microorganisms using the agar diffusion method. Forty-eight out of the 49 endophytic fungi were identified and grouped into 14 taxa. Cylindrocarpon sp. was the dominant species isolated from S. involucrata, followed by Phoma sp. and Fusarium sp. Among the 49 endophytic fungi, 9 root isolates having darkly pigmented, septate hyphae were identified as dark septate endophytic (DSE) fungus, and 12 fungi inhibited at least one test microorganism. Moreover, 5 strains showed a broader spectrum of antimicrobial activity and 4 strains displayed strong inhibition (+++) against pathogenic fungi. The results indicate that endophytic fungi isolated from S. involucrata are diverse in species and a potential source of antimicrobial agents.

Buwchitin: a ruminal peptide with antimicrobial potential against Enterococcus faecalis

NASA Astrophysics Data System (ADS)

Oyama, Linda B.; Crochet, Jean-Adrien; Edwards, Joan E.; Girdwood, Susan E.; Cookson, Alan R.; Fernandez-Fuentes, Narcis; Hilpert, Kai; Golyshin, Peter N.; Golyshina, Olga V.; Privé, Florence; Hess, Matthias; Mantovani, Hilario C.; Creevey, Christopher J.; Huws, Sharon A.

2017-07-01

Antimicrobial peptides (AMPs) are gaining popularity as alternatives for treatment of bacterial infections and recent advances in omics technologies provide new platforms for AMP discovery. We sought to determine the antibacterial activity of a novel antimicrobial peptide, buwchitin, against Enterococcus faecalis. Buwchitin was identified from a rumen bacterial metagenome library, cloned, expressed and purified. The antimicrobial activity of the recombinant peptide was assessed using a broth microdilution susceptibility assay to determine the peptide's killing kinetics against selected bacterial strains. The killing mechanism of buwchitin was investigated further by monitoring its ability to cause membrane depolarization (diSC3(5) method) and morphological changes in E. faecalis cells. Transmission electron micrographs of buwchitin treated E. faecalis cells showed intact outer membranes with blebbing, but no major damaging effects and cell morphology changes. Buwchitin had negligible cytotoxicity against defibrinated sheep erythrocytes. Although no significant membrane leakage and depolarization was observed, buwchitin at minimum inhibitory concentration (MIC) was bacteriostatic against E. faecalis cells and inhibited growth in vitro by 70% when compared to untreated cells. These findings suggest that buwchitin, a rumen derived peptide, has potential for antimicrobial activity against E. faecalis.

Antimicrobial Effect of 7-O-Butylnaringenin, a Novel Flavonoid, and Various Natural Flavonoids against Helicobacter pylori Strains

PubMed Central

Moon, Sun Hee; Lee, Jae Hoon; Kim, Kee-Tae; Park, Yong-Sun; Nah, Seung-Yeol; Ahn, Dong Uk; Paik, Hyun-Dong

2013-01-01

The antimicrobial effect of a novel flavonoid (7-O-butylnaringenin) on Helicobacter pylori 26695, 51, and SS1 strains and its inhibitory effect on the urease activity of the strains were evaluated and compared with those of several natural flavonoids. First, various flavonoids were screened for antimicrobial activities using the paper disc diffusion method. Hesperetin and naringenin showed the strongest antimicrobial effects among the natural flavonoids tested, and thus hesperetin and naringenin were selected for comparison with 7-O-butylnaringenin. The antimicrobial effect of 7-O-butylnaringenin was greater than that of the hesperetin and naringenin. H. pylori 51 was more sensitive to 7-O-butylnaringenin (2 log reduction of colony forming units, p < 0.05) than the other two strains at 200 μM. 7-O-Butylnaringenin also showed the highest inhibitory effect against urease activity of H. pylori. Morphological changes of H. pylori 26695 treated with these flavonoids indicated that both hesperetin and 7-O-butylnaringenin at 200 μM damaged the cell membranes. PMID:24169409

Rhamnolipids as emulsifying agents for essential oil formulations: antimicrobial effect against Candida albicans and methicillin-resistant Staphylococcus aureus.

PubMed

Haba, Ester; Bouhdid, Samira; Torrego-Solana, Noelia; Marqués, A M; Espuny, M José; García-Celma, M José; Manresa, Angeles

2014-12-10

This work examines the influence of essential oil composition on emulsification with rhamnolipids and their use as therapeutic antimicrobial agents against two opportunistic pathogens, methicillin-resistant Staphylococcus aureus (MRSA) and Candida albicans. Rhamnolipids, produced by Pseudomonas aeruginosa, with waste frying oil as the carbon source, were composed of eight rhamnolipid homologues. The rhamnolipid mixture was used to produce emulsions containing essential oils (EOs) of Melaleuca alternifolia, Cinnamomum verum, Origanum compactum and Lavandula angustifolia using the titration method. Ternary phase diagrams were designed to evaluate emulsion stability, which differed depending on the essential oil. The in vitro antimicrobial activity of the EOs alone and the emulsions was evaluated. The antimicrobial activity presented by the essential oils alone increased with emulsification. The surface properties of rhamnolipids contribute to the positive dispersion of EOs and thus increase their availability and antimicrobial activity against C. albicans and S. aureus. Therefore, rhamnolipid-based emulsions represent a promising approach to the development of EO delivery systems. Copyright © 2014 Elsevier B.V. All rights reserved.

Evaluation of Phenolic Compounds and Antioxidant and Antimicrobial Activities of Some Common Herbs.

PubMed

Abdul Qadir, Muhammad; Shahzadi, Syeda Kiran; Bashir, Asad; Munir, Adil; Shahzad, Shabnam

2017-01-01

The study was designed to evaluate the phenolic, flavonoid contents and antioxidant and antimicrobial activities of onion ( Allium cepa ), garlic ( Allium sativum ), mint ( Mentha spicata ), thyme ( Thymus vulgaris ), oak ( Quercus ), aloe vera ( Aloe barbadensis Miller), and ginger ( Zingiber officinale ). All extracts showed a wide range of total phenolic contents, that is, 4.96 to 98.37 mg/100 g gallic acid equivalents, and total flavonoid contents, that is, 0.41 to 17.64 mg/100 g catechin equivalents. Antioxidant activity (AA) was determined by measuring reducing power, inhibition of peroxidation using linoleic acid system, and 2,2-diphenyl-1-picrylhydrazyl radical (DPPH) scavenging activity. Different extracts inhibited oxidation of linoleic acid by 16.6-84.2% while DPPH radical scavenging activity (IC 50 values) ranged from 17.8% to 79.1  μ g/mL. Reducing power at 10 mg/mL extract concentration ranged from 0.11 to 0.84 nm. Furthermore the extracts of these medicinal herbs in 80% methanol, 80% ethanol, 80% acetone, and 100% water were screened for antimicrobial activity by disc diffusion method against selected bacterial strains, Staphylococcus aureus , Escherichia coli , Bacillus subtilis , and Pasteurella multocida , and fungal strains, Aspergillus niger , Aspergillus flavus, Rhizopus solani , and Alternaria alternata . The extracts show better antimicrobial activity against bacterial strains as compared to fungal strains. Results of various assays were analyzed statistically by applying appropriate statistical methods.

Evaluation of Phenolic Compounds and Antioxidant and Antimicrobial Activities of Some Common Herbs

PubMed Central

Abdul Qadir, Muhammad; Bashir, Asad; Munir, Adil

2017-01-01

The study was designed to evaluate the phenolic, flavonoid contents and antioxidant and antimicrobial activities of onion (Allium cepa), garlic (Allium sativum), mint (Mentha spicata), thyme (Thymus vulgaris), oak (Quercus), aloe vera (Aloe barbadensis Miller), and ginger (Zingiber officinale). All extracts showed a wide range of total phenolic contents, that is, 4.96 to 98.37 mg/100 g gallic acid equivalents, and total flavonoid contents, that is, 0.41 to 17.64 mg/100 g catechin equivalents. Antioxidant activity (AA) was determined by measuring reducing power, inhibition of peroxidation using linoleic acid system, and 2,2-diphenyl-1-picrylhydrazyl radical (DPPH) scavenging activity. Different extracts inhibited oxidation of linoleic acid by 16.6–84.2% while DPPH radical scavenging activity (IC50 values) ranged from 17.8% to 79.1 μg/mL. Reducing power at 10 mg/mL extract concentration ranged from 0.11 to 0.84 nm. Furthermore the extracts of these medicinal herbs in 80% methanol, 80% ethanol, 80% acetone, and 100% water were screened for antimicrobial activity by disc diffusion method against selected bacterial strains, Staphylococcus aureus, Escherichia coli, Bacillus subtilis, and Pasteurella multocida, and fungal strains, Aspergillus niger, Aspergillus flavus, Rhizopus solani, and Alternaria alternata. The extracts show better antimicrobial activity against bacterial strains as compared to fungal strains. Results of various assays were analyzed statistically by applying appropriate statistical methods. PMID:28316626

The diversity and antimicrobial activity of endophytic fungi associated with medicinal plant Baccharis trimera (Asteraceae) from the Brazilian savannah.

PubMed

Vieira, Mariana L A; Johann, Susana; Hughes, Frederic M; Rosa, Carlos A; Rosa, Luiz H

2014-12-01

The fungal endophyte community associated with Baccharis trimera, a Brazilian medicinal plant, was characterized and screened for its ability to present antimicrobial activity. By using molecular methods, we identified and classified the endophytic fungi obtained into 25 different taxa from the phyla Ascomycota and Basidiomycota. The most abundant species were closely related to Diaporthe phaseolorum, Pestalotiopsis sp. 1, and Preussia pseudominima. The differences observed in endophytic assemblages from different B. trimera specimens might be associated with their crude extract activities. Plants that had higher α-biodiversity were also those that contributed more to the regional (γ) diversity. All fungal isolates were cultured and their crude extracts screened to examine the antimicrobial activities. Twenty-three extracts (12.8%) displayed antimicrobial activities against at least one target microorganism. Among these extracts, those obtained from Epicoccum sp., Pestalotiopsis sp. 1, Cochliobolus lunatus, and Nigrospora sp. presented the best minimum inhibitory concentration values. Our results show that the endophytic fungal community associated with the medicinal plant B. trimera included few dominant bioactive taxa, which may represent sources of compounds with antifungal activity. Additionally, the discovery of these bioactive fungi in association with B. trimera suggests that Brazilian plants used as folk medicine may shelter a rich fungal diversity as well as taxa able to produce bioactive metabolites with antimicrobial activities.

Diverse deep-sea fungi from the South China Sea and their antimicrobial activity.

PubMed

Zhang, Xiao-Yong; Zhang, Yun; Xu, Xin-Ya; Qi, Shu-Hua

2013-11-01

We investigated the diversity of fungal communities in nine different deep-sea sediment samples of the South China Sea by culture-dependent methods followed by analysis of fungal internal transcribed spacer (ITS) sequences. Although 14 out of 27 identified species were reported in a previous study, 13 species were isolated from sediments of deep-sea environments for the first report. Moreover, these ITS sequences of six isolates shared 84-92 % similarity with their closest matches in GenBank, which suggested that they might be novel phylotypes of genera Ajellomyces, Podosordaria, Torula, and Xylaria. The antimicrobial activities of these fungal isolates were explored using a double-layer technique. A relatively high proportion (56 %) of fungal isolates exhibited antimicrobial activity against at least one pathogenic bacterium or fungus among four marine pathogenic microbes (Micrococcus luteus, Pseudoaltermonas piscida, Aspergerillus versicolor, and A. sydowii). Out of these antimicrobial fungi, the genera Arthrinium, Aspergillus, and Penicillium exhibited antibacterial and antifungal activities, while genus Aureobasidium displayed only antibacterial activity, and genera Acremonium, Cladosporium, Geomyces, and Phaeosphaeriopsis displayed only antifungal activity. To our knowledge, this is the first report to investigate the diversity and antimicrobial activity of culturable deep-sea-derived fungi in the South China Sea. These results suggest that diverse deep-sea fungi from the South China Sea are a potential source for antibiotics' discovery and further increase the pool of fungi available for natural bioactive product screening.

Assessment of Antimicrobial and Antioxidant Activities of Nepeta trachonitica: Analysis of Its Phenolic Compounds Using HPLC-MS/MS

PubMed Central

Köksal, Ekrem; Tohma, Hatice; Kılıç, Ömer; Alan, Yusuf; Aras, Abdülmelik; Gülçin, İlhami; Bursal, Ercan

2017-01-01

Continuing our work on the sources of natural bioactive compounds, we evaluated the antimicrobial and antioxidant activities of Nepeta trachonitica as well as its major phenolic content using the high-performance liquid chromatography-mass spectrometry/mass spectrometry (HPLC-MS/MS) technique. For antioxidant activity, ferric reducing antioxidant power (FRAP) and cupric ion reducing antioxidant capacity (CUPRAC) methods were performed to measure the reducing power and 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay was employed to evaluate the radical scavenging activity of the sample. For antimicrobial activity, three Gram-positive and four Gram-negative microbial species as well as three fungi species were tested. N. trachonitica appeared to have reasonable antioxidant activity and decent antimicrobial activity as indicated by the inhibition of the organisms’ growth. The most susceptible species were Bacillus subtilis ATCC 6633 and Escherichia coli ATCC 11229 among the organisms tested. Ethanol extract of the plant has the highest effect on Saccharomyces cerevisiae but no effect on Yarrowia lipolytica. The HPLC-MS/MS analysis showed that at least 11 major phenolic compounds of N. trachonitica exist, the major ones being rosmarinic acid, chlorogenic acid and quinic acid. The obtained results suggest that N. trachonitica could be a promising source for food and nutraceutical industries because of its antimicrobial and antioxidant properties and phenolic compounds. PMID:28505129

Antimicrobial activity of Anonna mucosa (Jacq.) grown in vivo and obtained by in vitroculture.

PubMed

Barboza, Thiago José de Souza; Ferreira, Andréa Fonseca; Ignacio, Ana Claudia de Paula Rosa; Albarello, Norma

2015-01-01

Brazilian flora includes numerous species of medicinal importance that can be used to develop new drugs. Plant tissue culture offers strategies for conservation and use of these species allowing continuous production of plants and bioactive substances. Annona mucosa has produced substances such as acetogenins and alkaloids that exhibit antimicrobial activities. The widespread use of antibiotics has led to an increase in multidrug-resistant bacteria, which represents a serious risk of infection. In view of this problem, the aim of this work was to evaluate the antibacterial potential of extracts of A. mucosa obtained by in vitro techniques and also cultured under in vivo conditions. Segments from seedlings were inoculated onto different culture media containing the auxin picloram and the cytokinin kinetin at different concentrations. The calluses obtained were used to produce cell suspension cultures. The materials were subjected to methanol extraction and subsequent fractionation in hexane and dichloromethane. The antimicrobial activity against 20 strains of clinical relevance was evaluated by the macrodilution method at minimum inhibitory and minimum bactericidal concentrations. The extracts showed selective antimicrobial activity, inhibiting the growth of Streptococcus pyogenes and Bacillus thuringiensis at different concentrations. The plant tissue culture methods produced plant materials with antibacterial properties, as well as in vivo grown plants. The antibacterial activity of material obtained through biotechnological procedures of A. mucosa is reported here for the first time.

Antimicrobial activity of Anonna mucosa (Jacq.) grown in vivo and obtained by in vitroculture

PubMed Central

de Souza Barboza, Thiago José; Ferreira, Andréa Fonseca; de Paula Rosa Ignacio, Ana Claudia; Albarello, Norma

2015-01-01

Brazilian flora includes numerous species of medicinal importance that can be used to develop new drugs. Plant tissue culture offers strategies for conservation and use of these species allowing continuous production of plants and bioactive substances. Annona mucosa has produced substances such as acetogenins and alkaloids that exhibit antimicrobial activities. The widespread use of antibiotics has led to an increase in multidrug-resistant bacteria, which represents a serious risk of infection. In view of this problem, the aim of this work was to evaluate the antibacterial potential of extracts of A. mucosa obtained by in vitro techniques and also cultured under in vivo conditions. Segments from seedlings were inoculated onto different culture media containing the auxin picloram and the cytokinin kinetin at different concentrations. The calluses obtained were used to produce cell suspension cultures. The materials were subjected to methanol extraction and subsequent fractionation in hexane and dichloromethane. The antimicrobial activity against 20 strains of clinical relevance was evaluated by the macrodilution method at minimum inhibitory and minimum bactericidal concentrations. The extracts showed selective antimicrobial activity, inhibiting the growth of Streptococcus pyogenes and Bacillus thuringiensis at different concentrations. The plant tissue culture methods produced plant materials with antibacterial properties, as well as in vivo grown plants. The antibacterial activity of material obtained through biotechnological procedures of A. mucosa is reported here for the first time. PMID:26413061

Antimicrobial activity of honey of africanized bee (Apis mellifera) and stingless bee, tiuba (Melipona fasciculata) against strains of Escherichia coli, Pseudomona aeruginosa and Staphylococcus aureus

NASA Astrophysics Data System (ADS)

Tenório, Eleuza Gomes; Alves, Natália Furtado; Mendes, Bianca Evanita Pimenta

2017-11-01

The objective of this study was to investigate the antimicrobial activity of honey of Africanized bees (Apis mellifera) and stingless bees (Melipona fasciculata), produced under the same flowering conditions, in municipalities of Baixada Maranhese, Brazil, against strains of pathogenic bacteria, Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus. In each municipality, the apiary and meliponario were less than 150 meters away from each other. The Kirby-Bauer method, and the diffusion technique of the agar plate through the extension of the inhibition in millimeters were used. The test results were negative for all samples, which did not demonstrate antimicrobial activity in any of the microorganisms tested.

In Vitro Antimicrobial Bioassays, DPPH Radical Scavenging Activity, and FTIR Spectroscopy Analysis of Heliotropium bacciferum

PubMed Central

2016-01-01

The present study deals with the antimicrobial, antioxidant, and functional group analysis of Heliotropium bacciferum extracts. Disc diffusion susceptibility method was followed for antimicrobial assessment. Noteworthy antimicrobial activities were recorded by various plant extracts against antibiotic resistant microorganisms. Plant flower extracts antioxidant activity was investigated against 2, 2-diphenyl-1-picryl hydrazyl radical by ultraviolet spectrophotometer (517 nm). Plant extracts displayed noteworthy radical scavenging activities at all concentrations (25–225 μg/mL). Notable activities were recorded by crude, chloroform and ethyl acetate extracts up to 88.27% at 225 μg/mL concentration. Compounds functional groups were examined by Fourier transform infrared spectroscopic studies. Alkanes, alkenes, alkyl halides, amines, carboxylic acids, amides, esters, alcohols, phenols, nitrocompounds, and aromatic compounds were identified by FTIR analysis. Thin layer chromatography bioautography was carried out for all plant extracts. Different bands were separated by various solvent systems. The results of the current study justify the use of Heliotropium bacciferum in traditional remedial herbal medicines. PMID:27597961

Antimicrobial activity and mechanism of the human milk-sourced peptide Casein201

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, Fan; Department of Endocrinology, Children's Hospital of Nanjing Medical University, Nanjing; Cui, Xianwei

Introduction: Casein201 is one of the human milk sourced peptides that differed significantly in preterm and full-term mothers. This study is designed to demonstrate the biological characteristics, antibacterial activity and mechanisms of Casein201 against common pathogens in neonatal infection. Methodology: The analysis of biological characteristics was done by bioinformatics. Disk diffusion method and flow cytometry were used to detect the antimicrobial activity of Casein201. Killing kinetics of Casein201 was measured using microplate reader. The antimicrobial mechanism of Casein201 was studied by electron microscopy and electrophoresis. Results: Bioinformatics analysis indicates that Casein201 derived from β-casein and showed significant sequence overlap. Antibacterialmore » assays showed Casein201 inhibited the growth of S taphylococcus aureus and Y ersinia enterocolitica. Ultrastructural analyses revealed that the antibacterial activity of Casein201 is through cytoplasmic structures disintegration and bacterial cell envelope alterations but not combination with DNA. Conclusion: We conclude the antimicrobial activity and mechanism of Casein201. Our data demonstrate that Casein201 has potential therapeutic value for the prevention and treatment of pathogens in neonatal infection.« less

Antimicrobial activity and mechanism of the human milk-sourced peptide Casein201.

PubMed

Zhang, Fan; Cui, Xianwei; Fu, Yanrong; Zhang, Jun; Zhou, Yahui; Sun, Yazhou; Wang, Xing; Li, Yun; Liu, Qianqi; Chen, Ting

2017-04-08

Casein201 is one of the human milk sourced peptides that differed significantly in preterm and full-term mothers. This study is designed to demonstrate the biological characteristics, antibacterial activity and mechanisms of Casein201 against common pathogens in neonatal infection. The analysis of biological characteristics was done by bioinformatics. Disk diffusion method and flow cytometry were used to detect the antimicrobial activity of Casein201. Killing kinetics of Casein201 was measured using microplate reader. The antimicrobial mechanism of Casein201 was studied by electron microscopy and electrophoresis. Bioinformatics analysis indicates that Casein201 derived from β-casein and showed significant sequence overlap. Antibacterial assays showed Casein201 inhibited the growth of S taphylococcus aureus and Y ersinia enterocolitica. Ultrastructural analyses revealed that the antibacterial activity of Casein201 is through cytoplasmic structures disintegration and bacterial cell envelope alterations but not combination with DNA. We conclude the antimicrobial activity and mechanism of Casein201. Our data demonstrate that Casein201 has potential therapeutic value for the prevention and treatment of pathogens in neonatal infection. Copyright © 2017 Elsevier Inc. All rights reserved.

Antimicrobial Activities of Three Medicinal Plants and Investigation of Flavonoids of Tripleurospermum disciforme.

PubMed

Tofighi, Zahra; Molazem, Maryam; Doostdar, Behnaz; Taban, Parisa; Shahverdi, Ahmad Reza; Samadi, Nasrin; Yassa, Narguess

2015-01-01

Rosa damascena, Tripleurospermum disciforme and Securigera securidaca were used as disinfectant agents and for treatment of some disease in folk medicine of Iran. The antimicrobial effects of different fractions of seeds extract of S. securidaca, petals extract of R. damascena and aerial parts extract of T. disciforme were examined against some gram positive, gram negative and fungi by cup plate diffusion method. The petroleum ether and chloroform fractions of S. securidaca showed antibacterial activities against Staphylococcus aureus and Pseudomonas aeruginosa, while its methanol fraction had no antibacterial effects. R. damascena petals extract demonstrated antibacterial activities against Bacillus cereus, Staphylococcus epidermidis, S. aureus and Pseudomonas aeruginosa. T. disciforme aerial parts extract exhibited antimicrobial effects only against S. aureus and S. epidermidis. None of the fractions had any antifungal activities. Therefore, present study confirmed utility of these plants as disinfectant agents. Six flavonoids were isolated from T. disciforme: Luteolin, Quercetin-7-O-glucoside, Kaempferol, Kaempferol-7-O-glucoside, Apigenin and Apigenin-7-O-glucoside. The flavonoids and the antimicrobial activity of T. disciforme are reported for the first time.

Antimicrobial Activities of Three Medicinal Plants and Investigation of Flavonoids of Tripleurospermum disciforme

PubMed Central

Tofighi, Zahra; Molazem, Maryam; Doostdar, Behnaz; Taban, Parisa; Shahverdi, Ahmad Reza; Samadi, Nasrin; Yassa, Narguess

2015-01-01

Rosa damascena, Tripleurospermum disciforme and Securigera securidaca were used as disinfectant agents and for treatment of some disease in folk medicine of Iran. The antimicrobial effects of different fractions of seeds extract of S. securidaca, petals extract of R. damascena and aerial parts extract of T. disciforme were examined against some gram positive, gram negative and fungi by cup plate diffusion method. The petroleum ether and chloroform fractions of S. securidaca showed antibacterial activities against Staphylococcus aureus and Pseudomonas aeruginosa, while its methanol fraction had no antibacterial effects. R. damascena petals extract demonstrated antibacterial activities against Bacillus cereus, Staphylococcus epidermidis, S. aureus and Pseudomonas aeruginosa. T. disciforme aerial parts extract exhibited antimicrobial effects only against S. aureus and S. epidermidis. None of the fractions had any antifungal activities. Therefore, present study confirmed utility of these plants as disinfectant agents. Six flavonoids were isolated from T. disciforme: Luteolin, Quercetin-7-O-glucoside, Kaempferol, Kaempferol-7-O-glucoside, Apigenin and Apigenin-7-O-glucoside. The flavonoids and the antimicrobial activity of T. disciforme are reported for the first time. PMID:25561928

Can disc diffusion susceptibility tests assess the antimicrobial activity of engineered nanoparticles?

NASA Astrophysics Data System (ADS)

Kourmouli, Angeliki; Valenti, Marco; van Rijn, Erwin; Beaumont, Hubertus J. E.; Kalantzi, Olga-Ioanna; Schmidt-Ott, Andreas; Biskos, George

2018-03-01

The use of disc diffusion susceptibility tests to determine the antibacterial activity of engineered nanoparticles (ENPs) is questionable because their low diffusivity practically prevents them from penetrating through the culture media. In this study, we investigate the ability of such a test, namely the Kirby-Bauer disc diffusion test, to determine the antimicrobial activity of Au and Ag ENPs having diameters from 10 to 40 nm on Escherichia coli cultures. As anticipated, the tests did not show any antibacterial effects of Au nanoparticles (NPs) as a result of their negligible diffusivity through the culture media. Ag NPs on the other hand exhibited a strong antimicrobial activity that was independent of their size. Considering that Ag, in contrast to Au, dissolves upon oxidation and dilution in aqueous solutions, the apparent antibacterial behavior of Ag NPs is attributed to the ions they release. The Kirby-Bauer method, and other similar tests, can therefore be employed to probe the antimicrobial activity of ENPs related to their ability to release ions rather than to their unique size-dependent properties. [Figure not available: see fulltext.

Antioxidant and Antimicrobial Activities of Quinoa (Chenopodium quinoa Willd.) Seeds Cultivated in Korea

PubMed Central

Park, Jin Hwa; Lee, Yun Jin; Kim, Yeon Ho; Yoon, Ki Sun

2017-01-01

The objective of this study was to investigate the antioxidant and antimicrobial properties of quinoa cultivated in Korea and to compare it with imported quinoa from the USA and Peru. The highest amount of total flavonoid contents (TFC) with 20.91 mg quercetin equivalents/100 g was measured in quinoa seed extract cultivated in Korea, while the total phenolic contents (TPC) were significantly higher in quinoa from the USA (16.28 mg gallic acid equivalents/100 g). In addition, quinoa extracts cultivated in Korea displayed a superior antioxidant ability in both, ferric reducing antioxidant power and 1,1-diphenyl-2-picrylhydrazyl values. There was a high correlation between TFC and antioxidant activity and a low correlation between TPC and antioxidant activity. The antimicrobial activity of the quinoa extracts was determined using a disc diffusion assay and optical density method. In both assays, the quinoa seed extracts did not have strong antimicrobial activity against foodborne bacteria, including Staphylococcus aureus, Listeria monocytogenes, Bacillus cereus, Escherichia coli, Salmonella Typhimurium, and Campylobacter jejuni. PMID:29043217

Engineering antimicrobial peptides with improved antimicrobial and hemolytic activities.

PubMed

Zhao, Jun; Zhao, Chao; Liang, Guizhao; Zhang, Mingzhen; Zheng, Jie

2013-12-23

The rapid rise of antibiotic resistance in pathogens becomes a serious and growing threat to medicine and public health. Naturally occurring antimicrobial peptides (AMPs) are an important line of defense in the immune system against invading bacteria and microbial infection. In this work, we present a combined computational and experimental study of the biological activity and membrane interaction of the computationally designed Bac2A-based peptide library. We used the MARTINI coarse-grained molecular dynamics with adaptive biasing force method and the umbrella sampling technique to investigate the translocation of a total of 91 peptides with different amino acid substitutions through a mixed anionic POPE/POPG (3:1) bilayer and a neutral POPC bilayer, which mimic the bacterial inner membrane and the human red blood cell (hRBC) membrane, respectively. Potential of mean force (PMF, free energy profile) was obtained to measure the free energy barrier required to transfer the peptides from the bulk water phase to the water-membrane interface and to the bilayer interior. Different PMF profiles can indeed identify different membrane insertion scenarios by mapping out peptide-lipid energy landscapes, which are correlated with antimicrobial activity and hemolytic activity. Computationally designed peptides were further tested experimentally for their antimicrobial and hemolytic activities using bacteria growth inhibition assay and hemolysis assay. Comparison of PMF data with cell assay results reveals a good correlation of the peptides between predictive transmembrane activity and antimicrobial/hemolytic activity. Moreover, the most active mutants with the balanced substitutions of positively charged Arg and hydrophobic Trp residues at specific positions were discovered to achieve the improved antimicrobial activity while minimizing red blood cell lysis. Such substitutions provide more effective and cooperative interactions to distinguish the peptide interaction with different lipid bilayers. This work provides a useful computational tool to better understand the mechanism and energetics of membrane insertion of AMPs and to rationally design more effective AMPs.

In vitro antimicrobial activity of ten medicinal plants against clinical isolates of oral cancer cases

PubMed Central

2011-01-01

Background Suppression of immune system in treated cancer patients may lead to secondary infections that obviate the need of antibiotics. In the present study, an attempt was made to understand the occurrence of secondary infections in immuno-suppressed patients along with herbal control of these infections with the following objectives to: (a) isolate the microbial species from the treated oral cancer patients along with the estimation of absolute neutrophile counts of patients (b) assess the in vitro antimicrobial activity medicinal plants against the above clinical isolates. Methods Blood and oral swab cultures were taken from 40 oral cancer patients undergoing treatment in the radiotherapy unit of Regional Cancer Institute, Pt. B.D.S. Health University, Rohtak, Haryana. Clinical isolates were identified by following general microbiological, staining and biochemical methods. The absolute neutrophile counts were done by following the standard methods. The medicinal plants selected for antimicrobial activity analysis were Asphodelus tenuifolius Cav., Asparagus racemosus Willd., Balanites aegyptiaca L., Cestrum diurnum L., Cordia dichotoma G. Forst, Eclipta alba L., Murraya koenigii (L.) Spreng. , Pedalium murex L., Ricinus communis L. and Trigonella foenum graecum L. The antimicrobial efficacy of medicinal plants was evaluated by modified Kirby-Bauer disc diffusion method. MIC and MFC were investigated by serial two fold microbroth dilution method. Results Prevalent bacterial pathogens isolated were Staphylococcus aureus (23.2%), Escherichia coli (15.62%), Staphylococcus epidermidis (12.5%), Pseudomonas aeruginosa (9.37%), Klebsiella pneumonia (7.81%), Proteus mirabilis (3.6%), Proteus vulgaris (4.2%) and the fungal pathogens were Candida albicans (14.6%), Aspergillus fumigatus (9.37%). Out of 40 cases, 35 (87.5%) were observed as neutropenic. Eight medicinal plants (A. tenuifolius, A. racemosus, B. aegyptiaca, E. alba, M. koenigii, P. murex R. communis and T. foenum graecum) showed significant antimicrobial activity (P < .05) against most of the isolates. The MIC and MFC values were ranged from 31 to 500 μg/ml. P. aeruginosa was observed highest susceptible bacteria (46.6%) on the basis of susceptible index. Conclusion It can be concluded that treated oral cancer patients were neutropenic and prone to secondary infection of microbes. The medicinal plant can prove as effective antimicrobial agent to check the secondary infections in treated cancer patients. PMID:21599889

Virtual screening of a milk peptide database for the identification of food-derived antimicrobial peptides.

PubMed

Liu, Yufang; Eichler, Jutta; Pischetsrieder, Monika

2015-11-01

Milk provides a wide range of bioactive substances, such as antimicrobial peptides and proteins. Our study aimed to identify novel antimicrobial peptides naturally present in milk. The components of an endogenous bovine milk peptide database were virtually screened for charge, amphipathy, and predicted secondary structure. Thus, 23 of 248 screened peptides were identified as candidates for antimicrobial effects. After commercial synthesis, their antimicrobial activities were determined against Escherichia coli NEB5α, E. coli ATCC25922, and Bacillus subtilis ATCC6051. In the tested concentration range (<2 mM), bacteriostatic activity of 14 peptides was detected including nine peptides inhibiting both Gram-positive and Gram-negative bacteria. The most effective fragment was TKLTEEEKNRLNFLKKISQRYQKFΑLPQYLK corresponding to αS2 -casein151-181 , with minimum inhibitory concentration (MIC) of 4.0 μM against B. subtilis ATCC6051, and minimum inhibitory concentrations of 16.2 μM against both E. coli strains. Circular dichroism spectroscopy revealed conformational changes of most active peptides in a membrane-mimic environment, transitioning from an unordered to α-helical structure. Screening of food peptide databases by prediction tools is an efficient method to identify novel antimicrobial food-derived peptides. Milk-derived antimicrobial peptides may have potential use as functional food ingredients and help to understand the molecular mechanisms of anti-infective milk effects. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Antibacterial and antifungal activities of some Mexican medicinal plants.

PubMed

Ruiz-Bustos, E; Velazquez, C; Garibay-Escobar, A; García, Z; Plascencia-Jatomea, M; Cortez-Rocha, M O; Hernandez-Martínez, J; Robles-Zepeda, R E

2009-12-01

In Mexico about 4,000 plant species have some medicinal use. The aim of this work was to evaluate the antimicrobial activity of six Mexican medicinal plants against fungi and Gram-positive and Gram-negative bacteria. Methanolic extracts were prepared from the Mexican medicinal plants Amphypteringium adstrigens, Castella tortuosa, Coutarea latiflora, Ibervillea sonorae, Jatropha cuneata, and Selaginella lepidophylla. The antibacterial and antifungal activities of the plants were determined by the broth microdilution method and the radial growth inhibition assay, respectively. All Mexican plants tested showed antimicrobial activity. Among the six plant extracts analyzed, J. cuneata showed the highest growth-inhibitory activity against fungi, Gram-positive and Gram-negative bacteria (J. cuneata > A. adstrigens > C. latiflora > C. tortuosa > I. sonorae approximately S. lepidophylla). Shigella flexneri and Staphylococcus aureus were the most susceptible bacteria to plant extracts. Complete inhibition of S. flexneri growth was observed with J. cuneata methanolic extract at 90 microg/mL. This plant extract also showed the strongest antifungal activity against Fusarium verticillioides and Aspergillus niger. Our data suggest that the medicinal plants tested have important antimicrobial properties. This is the first report describing the antimicrobial activities of several of the Mexican medicinal plants used in this study.

Antimicrobial activity of southern African medicinal plants with dermatological relevance: From an ethnopharmacological screening approach, to combination studies and the isolation of a bioactive compound.

PubMed

Mabona, Unathi; Viljoen, Alvaro; Shikanga, Emmanual; Marston, Andrew; Van Vuuren, Sandy

2013-06-21

Ethnobotanical reports on more than 100 southern African medicinal plants with dermatological relevance have been highlighted, yet there is still limited scientific data to support claims for their antimicrobial effectiveness against skin pathogens. Guided by ethnobotanical data, this paper explores the antimicrobial efficacies of southern African medicinal plants used to treat skin ailments. To investigate the antimicrobial properties of southern African medicinal plants against dermatologically relevant pathogens. The study also aimed at providing a scientific rationale for the traditional use of plant combinations to treat skin diseases and the isolation of the bio-active compound from the most active species, Aristea ecklonii (Iridaceae). Organic and aqueous extracts (132) were prepared from 47 plant species and screened for antimicrobial properties against dermatologically relevant pathogens using the micro-titre plate dilution method. Four different plant combinations were investigated for interactive properties and the sum of the fractional inhibitory concentration (ƩFIC) calculated. Isobolograms were used to further investigate the antimicrobial interactive properties of Pentanisia prunelloides combined with Elephantorrhiza elephantina at varied ratios. A bioactivity-guided fractionation process was adopted to fractionate the organic leaf extract of Aristea ecklonii. Plants demonstrating notable broad-spectrum activities (MIC values ≤1.00mg/ml) against the tested pathogens included extracts from Aristea ecklonii, Chenopodium ambrosioides, Diospyros mespiliformis, Elephantorrhiza elephantina, Eucalyptus camaldulensis, Gunnera perpensa, Harpephyllum caffrum, Hypericum perforatum, Melianthus comosus, Terminalia sericea and Warburgia salutaris. The organic extract of Elephantorrhiza elephantina, a plant reportedly used to treat acne vulgaris, demonstrated noteworthy antimicrobial activity (MIC value of 0.05mg/ml) against Propionibacterium acnes. Similarly, Diospyros mespiliformis reported for its traditional use to treat ringworm, also displayed noteworthy antimicrobial activity against Trichophyton mentagrophytes (MIC 0.10mg/ml) and Microsporum canis (MIC 0.50mg/ml). The aqueous root extracts of Pentanisia prunelloides combined (1:1) with Elephantorrhiza elephantina displayed synergistic interactions (ƩFIC values 0.31-0.38) against Staphylococcus aureus, gentamycin-methicillin resistant Staphylococcus aureus, Staphylococcus epidermidis and Candida albicans. Fractionation of Aristea ecklonii resulted in the isolation of the known bio-active compound, plumbagin, displaying noteworthy antimicrobial activity (MIC range between 2.00μg/ml and 16.00μg/ml). Most of the plant extracts demonstrated pathogen specific antimicrobial effects with a few exhibiting broad-spectrum activities. Positive antimicrobial effects noted for plants such as Elephantorrhiza elephantina and Diospyros mespiliformis used for acne vulgaris and ringworm infections, respectively, give some validation to their reported traditiona l uses. Synergistic interactions noted for Pentanisia prunelloides combined with Elephantorrhiza elephantina validate an enhanced antimicrobial effect when used in combination. Noteworthy antimicrobial activities (MIC range between 2.00μg/ml and 16.00μg/ml) were observed for plumbagin isolated from Aristea ecklonii. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Production of the antimicrobial peptides Caseicin A and B by Bacillus isolates growing on sodium caseinate.

PubMed

Kent, R M; Guinane, C M; O'Connor, P M; Fitzgerald, G F; Hill, C; Stanton, C; Ross, R P

2012-08-01

The aim of this study was to identify Bacillus isolates capable of degrading sodium caseinate and subsequently to generate bioactive peptides with antimicrobial activity. Sodium caseinate (2.5% w/v) was inoculated separately with 16 Bacillus isolates and allowed to ferment overnight. Protein breakdown in the fermentates was analysed using gel permeation-HPLC (GP-HPLC) and screened for peptides (<3-kDa) with MALDI-TOF mass spectrometry. Caseicin A (IKHQGLPQE) and caseicin B (VLNENLLR), two previously characterized antimicrobial peptides, were identified in the fermentates of both Bacillus cereus and Bacillus thuringiensis isolates. The caseicin peptides were subsequently purified by RP-HPLC and antimicrobial assays indicated that the peptides maintained the previously identified inhibitory activity against the infant formula pathogen Cronobacter sakazakii. We report a new method using Bacillus sp. to generate two previously characterized antimicrobial peptides from casein. This study highlights the potential to exploit Bacillus sp. or the enzymes they produce for the generation of bioactive antimicrobial peptides from bovine casein. © 2012 The Authors. Letters in Applied Microbiology © 2012 The Society for Applied Microbiology.

Detection of antimicrobial activity of banana peel (Musa paradisiaca L.) on Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans: An in vitro study.

PubMed

Kapadia, Suraj Premal; Pudakalkatti, Pushpa S; Shivanaikar, Sachin

2015-01-01

Banana is used widely because of its nutritional values. In past, there are studies that show banana plant parts, and their fruits can be used to treat the human diseases. Banana peel is a part of banana fruit that also has the antibacterial activity against microorganisms but has not been studied extensively. Since, there are no studies that relate the antibacterial activity of banana peel against periodontal pathogens. Hence, the aim of this study is to determine the antimicrobial activity of banana peel extract on Porphyromonas gingivalis (P. gingivalis) and Aggregatibacter actinomycetemcomitans (A. actinomycetemcomitans). Standard strains of P. gingivalis and A. actinomycetemcomitans were used in this study which was obtained from the in-house bacterial bank of Department of Molecular Biology and Immunology at Maratha Mandal's Nathajirao G. Halgekar Institute of Dental Sciences and Research Centre. The banana peel extract was prepared, and the antibacterial activity was assessed using well agar diffusion method and minimum inhibitory concentration was assessed using serial broth dilution method. In the current study, both the tested microorganisms showed antibacterial activity. In well diffusion method, P. gingivalis and A. actinomycetemcomitans showed 15 mm and 12 mm inhibition zone against an alcoholic extract of banana peel, respectively. In serial broth dilution method P. gingivalis and A. actinomycetemcomitans were sensitive until 31.25 μg/ml dilutions. From results of the study, it is suggested that an alcoholic extract of banana peel has antimicrobial activity against P. gingivalis and A. actinomycetemcomitans.

Antimicrobial susceptibilities of Stomatococcus mucilaginosus and of Micrococcus spp.

PubMed Central

von Eiff, C; Herrmann, M; Peters, G

1995-01-01

The in vitro susceptibilities of 63 isolates of Stomatococcus mucilaginosus and of 188 isolates of Micrococcus spp. to 18 antimicrobial agents were determined by the agar dilution method. Many beta-lactams, imipenem, rifampin, and the glycopeptides were shown to be active in vitro against Stomatococcus and Micrococcus isolates, whereas the activities of antibiotics such as some aminoglycosides, erythromycin, and fosfomycin against an important number of these microorganisms are limited. PMID:7695321

Efficacy of newly formulated ointment containing 20% active antimicrobial honey in treatment of burn wound infections.

PubMed

Tasleem, Samiyah; Naqvi, Syed Baqir Shyum; Khan, Saadat Ali; Hashmi, Khursheed

2013-01-01

Honey has been familiar to possess antimicrobial potential to clear infection against burn wound infecting bacteria since ancient times. The objective of the study was to evaluate the efficacy of the newly formulated honey ointment during the treatment of burn wound infections. The Experimental (Non comparative) study was conducted at outpatient department of Dermatology, Fauji Foundation Hospital, Rawalpindi from November 2009 to October 2010. The antimicrobial activity of different Pakistani floral sources (Acacia nilotica species indica, Zizyphus, Helianthus annuus and Carisa opaca) honey samples were investigated by disc diffusion method against freshly isolated burn wounds infecting bacteria. Ointment containing 20% active antimicrobial honey was formulated as a sovereign remedy. A total number of twenty patients with second degree of burn wounds on different parts of the body were studied. A thin layer of honey ointment on gauze was applied to the wounds two to three times a day up to the complete healing. During microbiological study, Pakistani honey samples were discovered to exhibit a very promising antimicrobial activity against all the wound infecting microorganisms tested. Clinical trials demonstrated that the topical application of honey ointment have significant control of infections arising form pathogenic bacteria and up to 100% healing results were observed in all burn wound cases within mean healing time for the duration of 8.15 (3-18) days time period. Newly formulated ointment containing 20% active antimicrobial honey is more effective and low-cost alternative preparation for the treatment of burn wound infections.

In vitro Antimicrobial Activity of Traditional Plant Used in Mestizo Shamanism from the Peruvian Amazon in Case of Infectious Diseases.

PubMed

Roumy, Vincent; Gutierrez-Choquevilca, Andréa-Luz; Lopez Mesia, Jean Pierre; Ruiz, Lastenia; Ruiz Macedo, Juan Celidonio; Abedini, Amin; Landoulsi, Ameni; Samaillie, Jennifer; Hennebelle, Thierry; Rivière, Céline; Neut, Christel

2015-10-01

Our survey was performed near Iquitos (Peruvian Amazon) and its surroundings and leads us to consider Mestizo ethnomedical practices. The plant species reported here are traditionally used for ailments related to microbial infections. Inhabitants of various ethnic origins were interviewed, and 52 selected plants extracts were evaluated for their antimicrobial properties against a panel of 36 sensitive and multi-resistant bacteria or yeast. The study aimed at providing information on antimicrobial plant extract activities and the ethnomedical context of Mestizo riverine populations from Loreto (Peru). The minimum inhibitory concentrations (MICs) of the plant crude extracts were carried out using the agar dilution method and ranged between 0.075 and 5.0 mg/ml. Of the 40 plants analyzed, 9 species showed MIC ≤0.3 mg/ml (Anacardium occidentale, Couroupita guianensis, Croton lechleri, Davilla rugosa, Erythrina amazonica, Jacaranda copaia subsp. Spectabilis, Oenocarpus bataua, Peperomia macrostachya, and Phyllanthus urinaria) for one or several of the 36 microorganisms and only 6 drug extracts were inactive. Among the 40 plants, 13 were evaluated for the first time for an antibacterial activity. This evaluation of the antimicrobial activity of 40 plants using an approved standard methodology allowed comparing those activities against various microbes to establish antimicrobial spectra of standardized plant extracts, and give support to the traditional use of these plants. It may also help discovering new chemical classes of antimicrobial agents that could serve against multi-resistant bacteria. This study leads us to consider Mestizo ethnomedical practices near Iquitos (Peruvian Amazon) and its surroundings. The plant species reported here are traditionally used for ailments related to microbial infections. 52 selected plants extracts were evaluated for their antimicrobial properties against a panel of 36 sensitive and multi resistant bacteria or yeast. The study aimed at providing information on antimicrobial plant extract activities and the ethnomedical context of Mestizo riverine populations from Loreto.

Critical physiological factors influencing the outcome of antimicrobial testing according to ISO 22196 / JIS Z 2801.

PubMed

Wiegand, Cornelia; Völpel, Andrea; Ewald, Andrea; Remesch, Markko; Kuever, Jan; Bauer, Janine; Griesheim, Stefanie; Hauser, Carolin; Thielmann, Julian; Tonndorf-Martini, Silke; Sigusch, Bernd W; Weisser, Jürgen; Wyrwa, Ralf; Elsner, Peter; Hipler, Uta-Christina; Roth, Martin; Dewald, Carolin; Lüdecke-Beyer, Claudia; Bossert, Jörg

2018-01-01

Bactericidal materials gained interest in the health care sector as they are capable of preventing material surfaces from microbial colonization and subsequent spread of infections. However, commercialization of antimicrobial materials requires proof of their efficacy, which is usually done using in vitro methods. The ISO 22196 standard (Japanese test method JIS Z 2801) is a method for measuring the antibacterial activity of daily goods. As it was found reliable for testing the biocidal activity of antimicrobially active materials and surface coatings most of the laboratories participating in this study used this protocol. Therefore, a round robin test for evaluating antimicrobially active biomaterials had to be established. To our knowledge, this is the first report on inaugurating a round robin test for the ISO 22196 / JIS Z 2801. The first round of testing showed that analyses in the different laboratories yielded different results, especially for materials with intermediate antibacterial effects distinctly different efficacies were noted. Scrutinizing the protocols used by the different participants and identifying the factors influencing the test outcomes the approach was unified. Four critical factors influencing the outcome of antibacterial testing were identified in a series of experiments: (1) incubation time, (2) bacteria starting concentration, (3) physiological state of bacteria (stationary or exponential phase of growth), and (4) nutrient concentration. To our knowledge, this is the first time these parameters have been analyzed for their effect on the outcome of testing according to ISO 22196 / JIS Z 2801. In conclusion, to enable assessment of the results obtained it is necessary to evaluate these single parameters in the test protocol carefully. Furthermore, uniform and robust definitions of the terms antibacterial efficacy / activity, bacteriostatic effects, and bactericidal action need to be agreed upon to simplify communication of results and also regulate expectations regarding antimicrobial tests, outcomes, and materials.

Isolation and identification of antimicrobial compound from Mentha longifolia L. leaves grown wild in Iraq

PubMed Central

Al-Bayati, Firas A

2009-01-01

Background Mentha longifolia L. (Lamiaceae) leaves have been traditionally implemented in the treatment of minor sore throat and minor mouth or throat irritation by the indigenous people of Iraq, although the compounds responsible for the medicinal properties have not been identified. In the present study, an antimicrobial compound was isolated and characterized, and its biological activity was assessed. Methods The compound was isolated and characterized from the extracted essential oil using different spectral techniques: TLC, FTIR spectra and HPLC. Antimicrobial activity of the compound was assessed using both disc diffusion and microdilution method in 96 multi-well microtiter plates. Results A known compound was isolated from the essential oil of the plant and was identified as (-) menthol. The isolated compound was investigated for its antimicrobial activity against seven selected pathogenic and non-pathogenic microorganisms: Staphylococcus aureus, Streptococcus mutans, Streptococcus faecalis, Streptococcus pyogenis, Lactobacillus acidophilus, Pseudomonas aeruginosa and the yeast Candida albicans. Menthol at different concentrations (1:1, 1:5, 1:10, 1:20) was active against all tested bacteria except for P. aeruginosa, and the highest inhibitory effect was observed against S. mutans (zone of inhibition: 25.3 mm) using the disc diffusion method. Minimal inhibitory concentration MIC values ranged from 15.6–125.0 μg/ml, and the most promising results were observed against S. aureus and S. mutans (MIC 15.6 μg/ml) while, S. faecalis, S. pyogenis and L. acidophilus ranked next (MIC 31.2 μg/ml). Furthermore, menthol achieved considerable antifungal activity against the yeast C. albicans (zone of inhibition range: 7.1–18.5 mm; MIC: 125.0). Conclusion The isolation of an antimicrobial compound from M. longifolia leaves validates the use of this plant in the treatment of minor sore throat and minor mouth or throat irritation. PMID:19523224

Critical physiological factors influencing the outcome of antimicrobial testing according to ISO 22196 / JIS Z 2801

PubMed Central

Völpel, Andrea; Ewald, Andrea; Remesch, Markko; Kuever, Jan; Bauer, Janine; Griesheim, Stefanie; Hauser, Carolin; Thielmann, Julian; Tonndorf-Martini, Silke; Sigusch, Bernd W.; Weisser, Jürgen; Wyrwa, Ralf; Elsner, Peter; Hipler, Uta-Christina; Roth, Martin; Dewald, Carolin; Lüdecke-Beyer, Claudia; Bossert, Jörg

2018-01-01

Bactericidal materials gained interest in the health care sector as they are capable of preventing material surfaces from microbial colonization and subsequent spread of infections. However, commercialization of antimicrobial materials requires proof of their efficacy, which is usually done using in vitro methods. The ISO 22196 standard (Japanese test method JIS Z 2801) is a method for measuring the antibacterial activity of daily goods. As it was found reliable for testing the biocidal activity of antimicrobially active materials and surface coatings most of the laboratories participating in this study used this protocol. Therefore, a round robin test for evaluating antimicrobially active biomaterials had to be established. To our knowledge, this is the first report on inaugurating a round robin test for the ISO 22196 / JIS Z 2801. The first round of testing showed that analyses in the different laboratories yielded different results, especially for materials with intermediate antibacterial effects distinctly different efficacies were noted. Scrutinizing the protocols used by the different participants and identifying the factors influencing the test outcomes the approach was unified. Four critical factors influencing the outcome of antibacterial testing were identified in a series of experiments: (1) incubation time, (2) bacteria starting concentration, (3) physiological state of bacteria (stationary or exponential phase of growth), and (4) nutrient concentration. To our knowledge, this is the first time these parameters have been analyzed for their effect on the outcome of testing according to ISO 22196 / JIS Z 2801. In conclusion, to enable assessment of the results obtained it is necessary to evaluate these single parameters in the test protocol carefully. Furthermore, uniform and robust definitions of the terms antibacterial efficacy / activity, bacteriostatic effects, and bactericidal action need to be agreed upon to simplify communication of results and also regulate expectations regarding antimicrobial tests, outcomes, and materials. PMID:29558480

Comparative studies on structural properties and antimicrobial potential of spinel ferrite nanoparticles synthesized using various methods

NASA Astrophysics Data System (ADS)

Baraliya, Jagdish D.; Rakhashiya, Purvi M.; Patel, Pooja P.; Thaker, Vrinda S.; Joshi, Hiren H.

2017-05-01

In this study, novel multifunctional magnetic iron-based nanoparticles (CoFe2O4) coated with silica, silica-DEG (diethylene glycol), PEG (polyethylene glycol) were synthesized using Auto Combustion Method (ACM), Co-precipitation Method (COPM), Citrate Precursor Method (CPM), Flash Combustion Method (FCM). These spinel ferrite nanoparticles also contain very high antibacterial properties to fulfill the requirements of a drug delivery system so that the antibiotic concentration could be minimized. A potential delivery system could be based on a ferromagnetic fluid. The effects of various preparation methods on the physical properties of the nanoparticles were examined. The nanoparticles were also tested against four human pathogenic bacteria (Gram negative E.coli, P. aeruginosa, Gram positive S. aureus, S. pyogenus) and two fungi (C. albicans, A.niger). It was revealed that a nanoparticle has strong antibacterial activity as compared to antifungal. Further, Gram positive bacteria are more affected than Gram negative bacteria. It was also clear that different methods of coating have great influence on the antimicrobial properties. It was observed that these nanoparticles have significantly different but potentially very high antimicrobial activities against the tested organisms than found elsewhere by other nanoparticles on the same organisms.

Evaluation of Fetal Intestinal Cell Growth and Antimicrobial Biofunctionalities of Donor Human Milk After Preparative Processes.

PubMed

Kanaprach, Pasinee; Pongsakul, Nutkridta; Apiwattanakul, Nopporn; Muanprasat, Chatchai; Supapannachart, Sarayut; Nuntnarumit, Pracha; Chutipongtanate, Somchai

2018-04-01

Donor human milk is considered the next best nutrition following mother's own milk to prevent neonatal infection and necrotizing enterocolitis in preterm infants who are admitted at neonatal intensive care unit. However, donor milk biofunctionalities after preparative processes have rarely been documented. To evaluate biofunctionalities preserved in donor milk after preparative processes by cell-based assays. Ten pools of donor milk were produced from 40 independent specimens. After preparative processes, including bacterial elimination methods (holder pasteurization and cold-sterilization microfiltration) and storage conditions (-20°C freezing storage and lyophilization) with varied duration of storage (0, 3, and 6, months), donor milk biofunctionalities were examined by fetal intestinal cell growth and antimicrobial assays. At baseline, raw donor milk exhibited 193.1% ± 12.3% of fetal intestinal cell growth and 42.4% ± 11.8% of antimicrobial activities against Escherichia coli. After bacteria eliminating processes, growth promoting activity was better preserved in pasteurized donor milk than microfiltrated donor milk (169.5% ± 14.3% versus 146.0% ± 11.8%, respectively; p < 0.005), whereas antimicrobial activity showed no difference between groups (38.3% ± 14.1% versus 53.7% ± 17.3%, respectively; p = 0.499). The pasteurized donor milk was further examined for the effects of storage conditions at 3 and 6 months. Freezing storage, but not lyophilization, could preserve higher growth-promoting activity during 6 months of storage (163.0% ± 9.4% versus 72.8% ± 6.2%, respectively; p < 0.005). Nonetheless, antimicrobial activity was lost at 6 months, regardless of the storage methods. This study revealed that fetal intestinal cell growth and antimicrobial assays could be applied to measure donor milk biofunctionalities and support the utilization of donor milk within 3 months after preparative processes.

Anti-microbial Activity of Tulsi {Ocimum Sanctum (Linn.)} Extract on a Periodontal Pathogen in Human Dental Plaque: An Invitro Study.

PubMed

Eswar, Pranati; Devaraj, C G; Agarwal, Payal

2016-03-01

Tulsi is a popular healing herb in Ayurvedic medicine. It is widely used in the treatment of several systemic diseases because of its anti-microbial property. However, studies documenting the effect of Tulsi on oral disease causing organisms are rare. Hence, an attempt was made to determine the effect of Tulsi on a periodontal microorganism in human dental plaque. To determine if Ocimum sanctum (Linn.) has an anti-microbial activity (Minimum Inhibitory Concentration and zone of inhibition) against Actinobacillus actinomycetemcomitans in human dental plaque and to compare the antimicrobial activity of Ocimum sanctum(Linn.) extract with 0.2% chlorhexidine as the positive control and dimethyl sulfoxide as the negative control. A lab based invitro experimental study design was adopted. Ethanolic extract of Ocimum sanctum (Linn.) was prepared by the cold extraction method. The extract was diluted with an inert solvent, dimethyl sulfoxide, to obtain ten different concentrations (1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%) of extract. Plaque sample was collected from 05 subjects diagnosed with periodontal disease. Isolation of Actinobacillus actinomycetemcomitans from plaque samples was done using Tryptic Soy Serum Bacitracin Vancomycin agar (TSBV) medium. Identification of Actinobacillus actinomycetemcomitans was done based on cultural, microscopic, biochemical characterization and multiple drug resistance patterns. Anti-microbial activity of Ocimum sanctum (Linn.) extract was tested by agar well-diffusion method against 0.2% chlorhexidine as a positive control and dimethyl sulfoxide as a negative control. The zone of inhibition was measured in millimeters using Vernier callipers. At the 6% w/v concentration of Ocimum sanctum (Linn.) extract, a zone of inhibition of 22 mm was obtained. This was the widest zone of inhibition observed among all the 10 different concentrations tested. The zone of inhibition for positive control was 25mm and no zone of inhibition was observed around the negative control. Ocimum sanctum (Linn.) extract demonstrated an antimicrobial activity against Actinobacillus actinomycetemcomitans. The maximum antimicrobial potential was observed at the 6% concentration level.

Synthesis, characteristics and antimicrobial activity of ZnO nanoparticles

NASA Astrophysics Data System (ADS)

Janaki, A. Chinnammal; Sailatha, E.; Gunasekaran, S.

2015-06-01

The utilization of various plant resources for the bio synthesis of metallic nano particles is called green technology and it does not utilize any harmful protocols. Present study focuses on the green synthesis of ZnO nano particles by Zinc Carbonate and utilizing the bio-components of powder extract of dry ginger rhizome (Zingiber officinale). The ZnO nano crystallites of average size range of 23-26 nm have been synthesized by rapid, simple and eco friendly method. Zinc oxide nano particles were characterized by using X-ray diffraction (XRD), Scanning Electron Microscope (SEM), Energy Dispersive X-ray spectroscopy (EDX). FTIR spectra confirmed the adsorption of surfactant molecules at the surface of ZnO nanoparticles and the presence of ZnO bonding. Antimicrobial activity of ZnO nano particles was done by well diffusion method against pathogenic organisms like Klebsiella pneumonia, Staphylococcus aureus and Candida albicans and Penicillium notatum. It is observed that the ZnO synthesized in the process has the efficient antimicrobial activity.

Synergy between antibiotics and natural agents results in increased antimicrobial activity against Staphylococcus epidermidis.

PubMed

Abidi, Syed Hani; Ahmed, Khalid; Sherwani, Sikander Khan; Kazmi, Shahana Urooj

2015-09-27

Staphylococcus epidermidis is one of the most frequent causes of biofilm-associated infections on indwelling medical devices. With the emergence of methicillin-resistant S. epidermidis (MRSE), there is an urgent need to discover novel active agents against a range of Gram-positive pathogens. We screened the clinical isolates of S. epidermidis for susceptibility/resistance against commonly prescribed antibiotics. Furthermore, we tested some natural agents alone and in combination with antibiotics to find possible synergistic antimicrobial effects. S. epidermidis clinical isolates were screened for susceptibility/resistance against vancomycin, erythromycin, tetracycline, chloramphenicol, ampicillin, ofloxacin, cephalexin, and gentamicin using the Kirby-Bauer disk diffusion method. The antimicrobial potential of Camellia sinensis, Juglans regia, and Hippophae rhamnoides alone and in combination with antibiotics were examined using the disk diffusion method, where the antimicrobial potential activity was measured in terms of formation of zones of inhibition. Most S. epidermidis isolates were found to be resistant to one or more antibiotics. Gentamycin and ofloxacin were found to be the most effective antibiotics against S. epidermidis isolates. Extracts of Hippophae rhamnoides, Juglans regia, and Camellia sinensis were found to be equally effective against S. epidermidis isolates. In combination with antibiotics, these extracts exhibited appreciable synergistic activity; the highest synergistic activity was observed with erythromycin and cephalexin. In the case of cephalexin, a reversion in resistance was observed. The plant extracts used in the study exhibited additive and synergistic antibacterial activity against S. epidermidis, hence providing an effective alternative to deal with the problem of multidrug resistance.

Antimicrobial activities of some selected traditional Ethiopian medicinal plants used in the treatment of skin disorders.

PubMed

Tadeg, Hailu; Mohammed, Endris; Asres, Kaleab; Gebre-Mariam, Tsige

2005-08-22

Hydroalcoholic extracts of eight species of medicinal plants, namely, Acokanthera schimperi (Apocynaceae), Calpurnia aurea (Leguminosae), Kalanchoe petitiana (Crassulaceae), Lippia adoensis (Verbenaceae), Malva parviflora (Malvaceae), Olinia rochetiana (Oliniaceae), Phytolacca dodecandra (Phytolaccaceae) and Verbascum sinaiticum (Scrophulariaceae), traditionally used in the treatment of various skin disorders were screened for antimicrobial activity against different strains of bacteria and fungi which are known to cause different types of skin infections. The tests were carried out using agar well diffusion method at three concentration levels (100, 50 and 25mg/ml) of the crude extracts. The MICs of the crude extracts of Lippia adoensis and Olinia rochetiana were determined by agar dilution method. Furthermore, the powdered leaves of Lippia adoensis and Olinia rochetiana were fractionated into different solvents of wide ranging polarity and the resulting fractions were screened for antimicrobial activity against the same organisms. Of all the plants tested, Lippia adoensis and Olinia rochetiana were found to be the most active species against bacterial and fungal strains, respectively. In addition, almost all species of plants were found to have activity on at least one microbial strain. The antimicrobial activity profile also showed that Staphylococcus aureus and Trichophyton mentagrophytes were the most susceptible bacterial and fungal strains, respectively. The results indicate the potential of these herbal drugs in treating microbial infections of the skin, thus, justifying their claimed uses in the treatment of various skin disorders, the majority of which are of infectious origin.

Antiproliferative and antimicrobial activity of traditional Kombucha and Satureja montana L. Kombucha.

PubMed

Cetojevic-Simin, D D; Bogdanovic, G M; Cvetkovic, D D; Velicanski, A S

2008-01-01

To carry out a preliminary investigation of the biological activity of Kombucha beverages from Camellia sinensis L. (black tea) and Satureja montana L. (winter savory tea), that have consuming acidity. Cell growth effect was measured by sulforhodamine B colorimetric assay on HeLa (cervix epithelioid carcinoma), HT-29 (colon adenocarcinoma), and MCF-7 (breast adenocarcinoma). Antimicrobial activity to bacteria, yeasts and moulds was determined by agar-well diffusion method. Consuming Kombuchas had the most expressive antimicrobial activity against all investigated bacteria, except Sarcina lutea, while unfermented tea samples had no activity. Traditional Kombucha showed higher activity against Staphylococcus aureus and Escherichia coli than acetic acid, while both neutralized Kombuchas had bacteriostatic activity on Salmonella enteritidis. Examined Kombuchas did not stimulate cell proliferation of the investigated cell lines. Antiproliferative activity of winter savory tea Kombucha was comparable to that of traditional Kombucha made from black tea. Furthermore, in HeLa cell line Satureja montana L. Kombucha induced cell growth inhibition by 20% (IC20) at lower concentration compared to the activity of water extract of Satureja montana L. obtained in our previous research. Presence of more active antiproliferative component(s) in Satureja montana L. Kombucha compared to Satureja montana L. water extract and antimicrobial component(s) other than acetic acid in both Kombuchas is suggested.

Chemical Analysis and Evaluation of Antioxidant, Antimicrobial, and Photoprotective Activities of Schinopsis brasiliensis Engl. (Anacardiaceae)

PubMed Central

de Lima-Saraiva, Sarah Raquel Gomes; Oliveira, Fernanda Granja da Silva; Junior, Raimundo Gonçalves de Oliveira; Araújo, Camila de Souza; de Oliveira, Ana Paula; César, Francine Celise Siqueira

2017-01-01

Schinopsis brasiliensis Engl. is a native plant of Caatinga which has high concentrations of compounds capable of absorbing ultraviolet light, suggesting its potential application for the development of sunscreen preparations. After its identification and collection, this vegetable drug was submitted to a physicochemical analysis through the preparation of ethanolic extract. The phytochemical screening and analysis of extracts were carried out by high-performance liquid chromatography (HPLC) evaluation. The antioxidant activity of the extract was evaluated by 2,2-diphenyl-1-picrylhydrazyl (DPPH) method and β-carotene bleaching test. Inhibitory hemolytic activity and morphological deformation of erythrocytes induced by H2O2 were also demonstrated and the antimicrobial activity was analyzed by the minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) method. For the in vitro determination of the sun protection factor (SPF), the spectrophotometric method was used. From the analyses carried out with this species, this plant showed significant results for the antioxidant and antimicrobial activities, as well as sunscreen action. Important flavonoids were identified. These data are an important step for the development of new photoprotective cosmetic with Caatinga species, revealing importance and representing another incentive for the preservation of the species involved and analyzed in the study. PMID:29124118

Detection of antimicrobial activity of banana peel (Musa paradisiaca L.) on Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans: An in vitro study

PubMed Central

Kapadia, Suraj Premal; Pudakalkatti, Pushpa S.; Shivanaikar, Sachin

2015-01-01

Introduction and Aim: Banana is used widely because of its nutritional values. In past, there are studies that show banana plant parts, and their fruits can be used to treat the human diseases. Banana peel is a part of banana fruit that also has the antibacterial activity against microorganisms but has not been studied extensively. Since, there are no studies that relate the antibacterial activity of banana peel against periodontal pathogens. Hence, the aim of this study is to determine the antimicrobial activity of banana peel extract on Porphyromonas gingivalis (P. gingivalis) and Aggregatibacter actinomycetemcomitans (A. actinomycetemcomitans). Material and Methods: Standard strains of P. gingivalis and A. actinomycetemcomitans were used in this study which was obtained from the in-house bacterial bank of Department of Molecular Biology and Immunology at Maratha Mandal's Nathajirao G. Halgekar Institute of Dental Sciences and Research Centre. The banana peel extract was prepared, and the antibacterial activity was assessed using well agar diffusion method and minimum inhibitory concentration was assessed using serial broth dilution method. Results: In the current study, both the tested microorganisms showed antibacterial activity. In well diffusion method, P. gingivalis and A. actinomycetemcomitans showed 15 mm and 12 mm inhibition zone against an alcoholic extract of banana peel, respectively. In serial broth dilution method P. gingivalis and A. actinomycetemcomitans were sensitive until 31.25 μg/ml dilutions. Conclusion: From results of the study, it is suggested that an alcoholic extract of banana peel has antimicrobial activity against P. gingivalis and A. actinomycetemcomitans. PMID:26681854

Design of Embedded-Hybrid Antimicrobial Peptides with Enhanced Cell Selectivity and Anti-Biofilm Activity

PubMed Central

Xu, Wei; Zhu, Xin; Tan, Tingting; Li, Weizhong; Shan, Anshan

2014-01-01

Antimicrobial peptides have attracted considerable attention because of their broad-spectrum antimicrobial activity and their low prognostic to induce antibiotic resistance which is the most common source of failure in bacterial infection treatment along with biofilms. The method to design hybrid peptide integrating different functional domains of peptides has many advantages. In this study, we designed an embedded-hybrid peptide R-FV-I16 by replacing a functional defective sequence RR7 with the anti-biofilm sequence FV7 embedded in the middle position of peptide RI16. The results demonstrated that the synthetic hybrid the peptide R-FV-I16 had potent antimicrobial activity over a wide range of Gram-negative and Gram-positive bacteria, as well as anti-biofilm activity. More importantly, R-FV-I16 showed lower hemolytic activity and cytotoxicity. Fluorescent assays demonstrated that R-FV-I16 depolarized the outer and the inner bacterial membranes, while scanning electron microscopy and transmission electron microscopy further indicated that this peptide killed bacterial cells by disrupting the cell membrane, thereby damaging membrane integrity. Results from SEM also provided evidence that R-FV-I16 inherited anti-biofilm activity from the functional peptide sequence FV7. Embedded-hybrid peptides could provide a new pattern for combining different functional domains and showing an effective avenue to screen for novel antimicrobial agents. PMID:24945359

Potential of the polymer poly-[2-(tert-butylamino) methylstyrene] as antimicrobial packaging material for meat products.

PubMed

Dohlen, S; Braun, C; Brodkorb, F; Fischer, B; Ilg, Y; Kalbfleisch, K; Lorenz, R; Robers, O; Kreyenschmidt, M; Kreyenschmidt, J

2016-10-01

The objective of the study was to investigate the antimicrobial potential of a new SAM(®) polymer poly(TBAMS) as packaging material for meat products. The influence of temperature, time and product factors on the antimicrobial activity of poly(TBAMS) against different bacteria was determined using a modified test method based on the Japanese Industrial Standard 2801:2000. Results showed a significant reduction in bacterial counts on poly(TBAMS) compared with the reference material of several meat-specific micro-organisms after 24 h at 7°C. Bacterial counts of Staphylococcus aureus, Listeria monocytogenes, Lactobacillus spp., Brochothrix thermosphacta and Escherichia coli were reduced by >4·0 log10  units. Pseudomonas fluorescens was less sensitive to poly(TBAMS) within 24 h between 2 and 7°C. Prolonging the storage time to 48 h, however, resulted in an increased reduction rate. Furthermore, antimicrobial activity was also observed if meat components in the form of meat extract, meat juice or bovine serum albumin protein were present. Antimicrobial activity was also achieved if inoculated with mixed cultures. Poly(TBAMS) showed antimicrobial properties under conditions typical for meat supply chains. Poly(TBAMS) bears a high potential to increase safety and shelf life of meat products. © 2016 The Society for Applied Microbiology.

GC/MS analysis and characterization of 2-Hexadecen-1-ol and beta sitosterol from Schimpera arabica extract for its bioactive potential as antioxidant and antimicrobial.

PubMed

Hidayathulla, S; Shahat, A A; Ahamad, S R; Al Moqbil, A A N; Alsaid, M S; Divakar, D D

2018-05-01

We evaluated the in vitro antioxidant and antimicrobial potential of Schimpera arabica extract and fractions (2-Hexadecen-1-ol and beta sitosterol). Free radical scavenging activity was estimated by using ABTS and DPPH methods, reducing power and iron chelation was studied to investigate antioxidant potential of the extracts. Well-diffusion method was utilized to evaluate the antimicrobial activity of the extracts. Gas chromatography-mass spectroscopy analysis of the extract revealed the presence of 27 compounds. Phenolic and flavonoid contents were found in high amount (7·6-18 mg GAE, mg g -1 ; 3·2-10·8 mg catechin, mg g -1 ) in dry plant material. Among all the extracts, 2-Hexadecen-1-ol and beta sitosterol were the major constituents of crude extract and exhibited significant antioxidant potential as well antimicrobial activity; however, all other fractions also exhibited fare degree of antioxidant potential. 93% DPPH was scavenged by 100 μg ml -1 of the ethyl acetate fraction; in ABTS assay chelation was 86·2 and 88% in ferric chloride reducing power assay. Schimpera arabica is naturally present and used in food preparation in most Arabian nations. The characterization of S. arabica would provide an insight into its medicinal use as home remedial for bacterial infection and as antioxidant. Significant and comparable antimicrobial activity was demonstrated by both 2-Hexadecen-1-ol and beta sitosterol fractions. The results suggest that S. arabica contain a good amount of natural antioxidants of medicinal importance. However, further investigations are needed to characterize the further activity of 2-Hexadecen-1-ol and beta sitosterol in vivo. © 2018 The Society for Applied Microbiology.

Isolation and identification of antimicrobial compound from Mentha longifolia L. leaves grown wild in Iraq.

PubMed

Al-Bayati, Firas A

2009-06-12

Mentha longifolia L. (Lamiaceae) leaves have been traditionally implemented in the treatment of minor sore throat and minor mouth or throat irritation by the indigenous people of Iraq, although the compounds responsible for the medicinal properties have not been identified. In the present study, an antimicrobial compound was isolated and characterized, and its biological activity was assessed. The compound was isolated and characterized from the extracted essential oil using different spectral techniques: TLC, FTIR spectra and HPLC. Antimicrobial activity of the compound was assessed using both disc diffusion and microdilution method in 96 multi-well microtiter plates. A known compound was isolated from the essential oil of the plant and was identified as (-) menthol. The isolated compound was investigated for its antimicrobial activity against seven selected pathogenic and non-pathogenic microorganisms: Staphylococcus aureus, Streptococcus mutans, Streptococcus faecalis, Streptococcus pyogenis, Lactobacillus acidophilus, Pseudomonas aeruginosa and the yeast Candida albicans. Menthol at different concentrations (1:1, 1:5, 1:10, 1:20) was active against all tested bacteria except for P. aeruginosa, and the highest inhibitory effect was observed against S. mutans (zone of inhibition: 25.3 mm) using the disc diffusion method. Minimal inhibitory concentration MIC values ranged from 15.6-125.0 microg/ml, and the most promising results were observed against S. aureus and S. mutans (MIC 15.6 microg/ml) while, S. faecalis, S. pyogenis and L. acidophilus ranked next (MIC 31.2 microg/ml). Furthermore, menthol achieved considerable antifungal activity against the yeast C. albicans (zone of inhibition range: 7.1-18.5 mm; MIC: 125.0). The isolation of an antimicrobial compound from M. longifolia leaves validates the use of this plant in the treatment of minor sore throat and minor mouth or throat irritation.

In vitro antimicrobial activity of natural toxins and animal venoms tested against Burkholderia pseudomallei

PubMed Central

Perumal Samy, R; Pachiappan, A; Gopalakrishnakone, P; Thwin, Maung M; Hian, Yap E; Chow, Vincent TK; Bow, Ho; Weng, Joseph T

2006-01-01

Background Burkholderia pseudomallei are the causative agent of melioidosis. Increasing resistance of the disease to antibiotics is a severe problem in treatment regime and has led to intensification of the search for new drugs. Antimicrobial peptides are the most ubiquitous in nature as part of the innate immune system and host defense mechanism. Methods Here, we investigated a group of venoms (snakes, scorpions and honey bee venoms) for antimicrobial properties against two strains of Gram-negative bacteria Burkholderia pseudomallei by using disc-diffusion assay for in vitro susceptibility testing. The antibacterial activities of the venoms were compared with that of the isolated L-amino acid oxidase (LAAO) and phospholipase A2 (PLA2s) enzymes. MICs were determined using broth dilution method. Bacterial growth was assessed by measurement of optical density at the lowest dilutions (MIC 0.25 mg/ml). The cell viability was measured using tetrazolium salts (XTT) based cytotoxic assay. Results The studied venoms showed high antimicrobial activity. The venoms of C. adamanteus, Daboia russelli russelli, A. halys, P. australis, B. candidus and P. guttata were equally as effective as Chloramphenicol and Ceftazidime (30 μg/disc). Among those tested, phospholipase A2 enzymes (crotoxin B and daboiatoxin) showed the most potent antibacterial activity against Gram-negative (TES) bacteria. Naturally occurring venom peptides and phospholipase A2 proved to possess highly potent antimicrobial activity against Burkholderia pseudomallei. The XTT-assay results showed that the cell survival decreased with increasing concentrations (0.05–10 mg/mL) of Crotalus adamanteus venom, with no effect on the cell viability evident at 0.5 mg/mL. Conclusion This antibacterial profile of snake venoms reported herein will be useful in the search for potential antibacterial agents against drug resistant microorganisms like B. pseudomallei. PMID:16784542

Enhancing the antimicrobial activity of d-limonene nanoemulsion with the inclusion of ε-polylysine.

PubMed

Zahi, Mohamed Reda; El Hattab, Mohamed; Liang, Hao; Yuan, Qipeng

2017-04-15

The objective of this research was to investigate the synergism between ε-polylysine and d-limonene and develop a novel nanoemulsion system by merging the positive effect of these two antimicrobial agents. Results from the checkerboard method showed that ε-polylysine and d-limonene exhibit strong synergistic and useful additive effects against Escherichia coli, Staphylococcus aureus, Bacillus subtilis and Saccharomyces cerevisiae. In addition, d-limonene nanoemulsion with the inclusion of ε-polylysine was successfully prepared by high pressure homogenizer technology. Its antimicrobial efficiency was compared with pure d-limonene nanoemulsion by measuring the minimal inhibitory concentration, electronic microscope observation and the leakage of the intercellular constituents. The results demonstrated a wide improvement of the antimicrobial activity of d-limonene nanoemulsion following the inclusion of ε-polylysine. Overall, the current study may have a valuable contribution to make in developing a more efficient antimicrobial system in the food industry. Copyright © 2016 Elsevier Ltd. All rights reserved.

Mushrooms as possible antioxidant and antimicrobial agents.

PubMed

Kosanić, Marijana; Ranković, Branislav; Dašić, Marko

2012-01-01

The aim of the study is to examine in-vitro antioxidant and antimicrobial activity of the acetonic and methanolic extracts of the mushrooms Boletus aestivalis, Boletus edulis and Leccinum carpini. Antioxidant activity was evaluated by using free radical scavenging activity and reducing power. In addition, total content of phenol and flavonoid in extracts were determined as pyrocatechol equivalent, and as rutin equivalent, respectively. As a result of the study acetonic extracts from Boletus edulis was more powerful antioxidant activity with IC50 value of 4.72 μg/mL which was similar or greater than the standard antioxidants, ascorbic acid (IC50 = 4.22 μg/mL), BHA (IC50 = 6.42 μg/mL) and α-tocopherol (IC50 = 62.43 μg/mL). Moreover, the tested extracts had effective reducing power. A significant relationship between total phenolic and flavonoid contents and their antioxidative activities was significantly observed. The antimicrobial activity of each extract was estimated by determination of the minimum inhibitory concentration by using microdilution plate method against five species of bacteria and five species of fungi. Generally, the tested mushroom extracts had relatively strong antimicrobial activity against the tested microorganisms. The minimum inhibitory concentration for both extracts related to the tested bacteria and fungi were 1.25 - 10 mg/ mL. The present study shows that tested mushroom species demonstrated a strong antioxidant and antimicrobial activity. It suggests that mushroom may be used as good sources of natural antioxidants and for pharmaceutical purposes in treating of various deseases.

A comparative study of the antioxidant, antimicrobial, cytotoxic and thrombolytic potential of the fruits and leaves of Spondias dulcis.

PubMed

Islam, Shawkat Md Aminul; Ahmed, Kh Tanvir; Manik, Mohammad Kawsar; Wahid, Md Arif; Kamal, Chowdhury Shafayat Ibne

2013-09-01

To investigate the antioxidant, antimicrobial, cytotoxic and thrombolytic property of the fruits and leaves of Spondias dulcis (S. dulcis). Methanolic extracts of fruits and leaves of S. dulcis were partitioned with chloroform and dichloromethane. The antioxidant potential of the crude extract and partitioned fractions were evaluated in terms of total phenolic content, total flavonoid content, DPPH radical scavenging potential, reducing potential and total antioxidant capacity by specific standard procedures. The antimicrobial activity was evaluated using disc diffusion method. The cytotoxicity was evaluated by using brine shrimp lethality bioassay and compared with vincristine sulfate. The thrombolytic activity was compared with streptokinase. The methanolic fruit extract exhibited the highest phenolic content, flavonoid content and antioxidant capacity, among the other extracts, with the highest DPPH radical scavenging activity at a concentration of 10 µg/mL (IC50: 1.91 µg/mL) and maximum reducing power at a concentration of 100 µg/mL (EC50: 3.58 µg/mL). Though all extract showed moderate antimicrobial activity against the bacterial strains, weak or no activity against fungus. The range of LC50 value of all extracts was 1.335-14.057 µg/mL which was far lower than the cut off index for cytotoxicity. All extracts exhibited statistically significant (P<0.001) thrombolytic activity. Our study suggested that S. dulcis exhibits antimicrobial activities against a wide variety of strains while it possesses significant antioxidant, cytotoxic and thrombolytic activity.

Antimicrobial activity of a 48-kDa protease (AMP48) from Artocarpus heterophyllus latex.

PubMed

Siritapetawee, J; Thammasirirak, S; Samosornsuk, W

2012-01-01

Artocarpus heterophyllus (jackfruit) is a latex producing plant. Plant latex is produced from secretory cells and contains many intergradients. It also has been used in folk medicine. This study aimed to purify and characterize the biological activities of a protease from jackfruit latex. A protease was isolated and purified from crude latex of a jackfruit tree by acid precipitation and ion exchange chromatography. The proteolytic activities of protein were tested using gelatin- and casein-zymography. The molecular weight and isoelectric point (pl) of protein were analysed by SDS/12.5% PAGE and 2D-PAGE, respectively. Antimicrobial activity of protein was analysed by broth microdilution method. In addition, the antibacterial activity of protein against Pseudomonas aeruginosa ATCC 27853 was observed and measured using atomic force microscopy (AFM) technique. The purified protein contained protease activity by digesting gelatin- and casein-substrates. The protease was designated as antimicrobial protease-48 kDa or AMP48 due to its molecular mass on SDS-PAGE was approximately 48 kDa. The isoelectric point (pl) of AMP48 was approximately 4.2. In addition, AMP48 contained antimicrobial activities by it could inhibit the growths of Pseudomonas aeruginosa ATCC 27853 and clinical isolated Candida albicans at minimum inhibitory concentration (MIC) 2.2 mg/ml and Minimum microbicidal concentration (MMC) 8.8 mg/ml. AFM image also supported the antimicrobial activities of AMP48 by the treated bacterial morphology and size were altered from normal.

Estimation of the bacteriocin ColE7 conjugation-based "kill" - "anti-kill" antimicrobial system by real-time PCR, fluorescence staining and bioluminescence assays.

PubMed

Maslennikova, I L; Kuznetsova, M V; Toplak, N; Nekrasova, I V; Žgur Bertok, D; Starčič Erjavec, M

2018-05-07

The efficiency of the bacteriocin, colicin ColE7, bacterial conjugation-based "kill" - "anti-kill" antimicrobial system, was assessed using real-time PCR, flow cytometry and bioluminescence. The ColE7 antimicrobial system consists of the genetically modified Escherichia coli strain Nissle 1917 harbouring a conjugative plasmid (derivative of the F-plasmid) encoding the "kill" gene (ColE7 activity gene) and a chromosomally encoded "anti-kill" gene (ColE7 immunity gene). On the basis of traJ gene expression in the killer donor cells, our results showed that the efficiency of the here studied antimicrobial system against target E. coli was higher at 4 than at 24 h. Flow cytometry was used to indirectly estimate DNase activity of the antimicrobial system, as lysis of target E. coli cells in the conjugative mixture with the killer donor strain led to reduction in cell cytosol fluorescence. According to a lux assay, E. coli TG1 (pXen lux + Ap r ) with constitutive luminescence were killed already after 2 h of treatment. Target sensor E. coli C600 with DNA damage SOS-inducible luminescence showed significantly lower SOS induction 6 and 24 h following treatment with the killer donor strain. Our results thus showed that bioluminescent techniques are quick and suitable for estimation of the ColE7 bacterial conjugation-based antimicrobial system antibacterial activity. Bacterial antimicrobial resistance is worldwide rising and causing deaths of thousands of patients infected with multi-drug resistant bacterial strains. In addition, there is a lack of efficient alternative antimicrobial agents. The significance of our research is the use of a number of methods (real-time PCR, flow cytometry and bioluminescence-based technique) to assess the antibacterial activity of the bacteriocin, colicin ColE7, bacterial conjugation-based "kill" - "anti-kill" antimicrobial system. Bioluminescent techniques proved to be rapid and suitable for estimation of antibacterial activity of ColE7 bacterial conjugation-based antimicrobial system and possibly other related systems. © 2018 The Society for Applied Microbiology.

Vetiver Essential Oil in Cosmetics: What Is New?

PubMed Central

Burger, Pauline; Landreau, Anne; Watson, Marie; Janci, Laurent; Cassisa, Viviane; Kempf, Marie; Azoulay, Stéphane; Fernandez, Xavier

2017-01-01

Background: Vetiver is a key ingredient for the perfume industry nowadays. However, with the constant and rapid changes of personal tastes, this appeal could vanish and this sector could decline quite quickly. New dissemination paths need to be found to tap this valuable resource. Methods: In this way, its potential use in cosmetics either as an active ingredient per se (with cosmeceutical significance or presenting antimicrobial activity) has hence been explored in vitro. Results: In this contribution, we demonstrated that vetiver essential oil displays no particularly significant and innovative cosmetic potential value in formulations apart from its scent already largely exploited. However, evaluated against twenty bacterial strains and two Candida species using the in vitro microbroth dilution method, vetiver oil demonstrated notably some outstanding activities against Gram-positive strains and against one Candida glabrata strain. Conclusions: Based on these findings, vetiver essential oil appears to be an appropriate aspirant for the development of an antimicrobial agent for medicinal purposes and for the development of a cosmetic ingredient used for its scent and displaying antimicrobial activity as an added value. PMID:28930256

Sulfur, selenium and tellurium pseudopeptides: synthesis and biological evaluation.

PubMed

Shaaban, Saad; Sasse, Florenz; Burkholz, Torsten; Jacob, Claus

2014-07-15

A new series of sulfur, selenium and tellurium peptidomimetic compounds was prepared employing the Passerini and Ugi isocyanide based multicomponent reactions (IMCRs). These reactions were clearly superior to conventional methods traditionally used for organoselenium and organotellurium synthesis, such as classical nucleophilic substitution and coupling methods. From the biological point of view, these compounds are of considerable interest because of suspected anticancer and antimicrobial activities. While the sulfur and selenium containing compounds generally did not show either anticancer or antimicrobial activities, their tellurium based counterparts frequently exhibited antimicrobial activity and were also cytotoxic. Some of the compounds synthesized even showed selective activity against certain cancer cells in cell culture. These compounds induced a cell cycle delay in the G0/G1 phase. At closer inspection, the ER and the actin cytoskeleton appeared to be the primary cellular targets of these tellurium compounds, in line with some of our previous studies. As most of these peptidomimetic compounds also comply with Lipinski's Rule of Five, they promise good bioavailability, which needs to be studied as part of future investigations. Copyright © 2014 Elsevier Ltd. All rights reserved.

Antimicrobial activity of plant compounds against Salmonella Typhimurium DT104 in ground pork and the influence of heat and storage on the antimicrobial activity.

PubMed

Chen, Cynthia H; Ravishankar, Sadhana; Marchello, John; Friedman, Mendel

2013-07-01

Salmonella enterica is a predominant foodborne pathogen that causes diarrheal illness worldwide. A potential method of inhibiting pathogenic bacterial growth in meat is through the introduction of plant-derived antimicrobials. The objectives of this study were to investigate the influence of heat (70°C for 5 min) and subsequent cold storage (4°C up to 7 days) on the effectiveness of oregano and cinnamon essential oils and powdered olive and apple extracts against Salmonella enterica serovar Typhimurium DT104 in ground pork and to evaluate the activity of the most effective antimicrobials (cinnamon oil and olive extract) at higher concentrations in heated ground pork. The surviving Salmonella populations in two groups (heated and unheated) of antimicrobial-treated pork were compared. Higher concentrations of the most effective compounds were then tested (cinnamon oil at 0.5 to 1.0% and olive extract at 3, 4, and 5%) against Salmonella Typhimurium in heated ground pork. Samples were stored at 4°C and taken on days 0, 3, 5, and 7 for enumeration of survivors. The heating process did not affect the activity of antimicrobials. Significant 1.3- and 3-log reductions were observed with 1.0% cinnamon oil and 5% olive extract, respectively, on day 7. The minimum concentration required to achieve . 1-log reduction in Salmonella population was 0.8% cinnamon oil or 4% olive extract. The results demonstrate the effectiveness of these antimicrobials against multidrug-resistant Salmonella Typhimurium in ground pork and their stability during heating and cold storage. The most active formulations have the potential to enhance the microbial safety of ground pork.

Determination of the antibiofilm, antiadhesive, and anti-MRSA activities of seven Salvia species.

PubMed

Al-Bakri, Amal G; Othman, Ghadeer; Afifi, Fatma U

2010-10-01

Several Salvia species are indigenous to Jordan and are widely used as beverages and spices and for their medicinal properties. The objective of the study was to establish the antimicrobial activities, including the antiadhesive and antibiofilm effects of seven different Salvia species. Methods used for planktonic culture included agar diffusion, broth microdilution, and minimal biocidal concentration determination while viable count was used for the determination of the antibiofilm and antiadhesion activities. Overnight cultures of reference strains of Candida albicans, Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus and clinical strains of methicillin-resistant S. aureus (MRSA) were used as test microorganisms. An antimicrobial activity toward planktonic cultures demonstrated a significant bacteriocidal activity (≥4 log cycle reduction) for the S. triloba extract against S. aureus including MRSA. Its volatile oil exhibited an antimicrobial activity covering all tested microorganisms with the exception of P. aeruginosa. S. triloba extract and volatile oil were successful in preventing and controlling the biofilm, demonstrating antiadhesion and antibiofilm activities, respectively. These reported activities for S. triloba extract and volatile oil allows their listing as potential antibiofilm and anti-MRSA natural agents. This might suggest their use as an antiseptic in the prophylaxis and treatment of S. aureus-associated skin infections. The antimicrobial activity of the other tested Salvia species was negligible.

Ultrafiltration and thermal processing effects on Maillard reaction products and biological properties of date palm sap syrups (Phoenix dactylifera L.).

PubMed

Makhlouf-Gafsi, Ines; Krichen, Fatma; Mansour, Riadh Ben; Mokni, Abir; Sila, Assad; Bougatef, Ali; Blecker, Christophe; Attia, Hamadi; Besbes, Souhail

2018-08-01

The effect of ultrafiltration process and temperature concentration on MRPs content and antioxidant, antimicrobial and cytotoxic properties of date palm sap syrups were investigated. MRPs were analyzed by HPLC. Antioxidant activity was evaluated by reducing power and DPPH free radical and H 2 O 2 scavenging activities. Antimicrobial activity was evaluated by the agar disk diffusion method. In vitro cytotoxic activity was examined by cell proliferation assay. Date sap syrups displayed strong antioxidant activities which are correlated 5HMF and 2F contents. In addition, concentration at 100 °C, unlike ultrafiltration process, enhanced significantly the antioxidant activities sap syrups and total phenolic contents. The antimicrobial activities showed marked activity against S. enterica, P. aeruginosa, S. aureus, L. monocytogenes with an inhibition zone of 21, 34, 27 and 34 mm respectively. Cytotoxicity assays showed that sap syrups can inhibit the proliferation of HeLa cell lines at high concentration. Published by Elsevier Ltd.

Starch-based polyurethane/CuO nanocomposite foam: Antibacterial effects for infection control.

PubMed

Ashjari, Hamid Reza; Dorraji, Mir Saeed Seyed; Fakhrzadeh, Vahid; Eslami, Hosein; Rasoulifard, Mohammad Hossein; Rastgouy-Houjaghan, Mehrdad; Gholizadeh, Pourya; Kafil, Hossein Samadi

2018-05-01

In the present study, a new method for the synthesis of the open cell flexible polyurethane foams (PUFs) was developed by using starch powder and the modification of closed cell foam formulation. Starch is the second largest polymeric carbohydrate as a macromolecule on this planet with a large number of glucose units. Copper oxide nanoparticles (CuO NPs) were synthesized by thermal degradation method at different temperatures of 400, 600 and 800 °C as antimicrobial agents. The antimicrobial activity of CuO NPs and commercial CuO powder against the main causes of hospital infections were tested. CuO 600 was the most effective antimicrobial agent and enhanced polymer matrix tensile strength with starch powder as new polyurethane foams (PUFs) cell opener with high tensile strength. The effects of parameters on tensile strength were optimized using response surface methodology (RSM). CuO NPs and PUF had optimal conditions and were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FT-IR). Foam synthesized at the optimal conditions had an open cell structure with high tensile strength and efficient antimicrobial activity that made them suitable to be used as an antimicrobial hospital mattress to control hospital infections. Copyright © 2018 Elsevier B.V. All rights reserved.

In vitro antimicrobial activity and antagonistic effect of essential oils from plant species.

PubMed

Toroglu, Sevil

2007-07-01

Kahramanmaras, is a developing city located in the southern part of Turkey Thymus eigii (M. Zohary and RH. Davis) Jalas, Pinus nigraAm. sub sp pallasiana and Cupressus sempervirens L. are the useful plants of the Kahramanmaras province and have been understudy since 2004 for the traditional uses of plants empiric drug, spice, herbal tea industry herbal gum and fuel. The study was designed to examine the antimicrobial activities of essential oils of these plants by the disc diffusion and minimum inhibitory concentration (MIC) methods. In addition, antimicrobial activity of Thymus eigii was researched by effects when it was used together with antibiotics and even when it was combined with other essential oils. When the results of this study were compared with vancomycin (30 mcg) and erytromycin (15 mcg) standards, it was found that Thymus eigii essential oil was particularly found to possess strongerantimicrobial activity whereas other essential oils showed susceptible or moderate activity However, antimicrobial activity changed also by in vitro interactions between antibiotics and Thymus eigii essential oil, also between essential oils of these plants and that of Thymus eigii causing synergic, additive, antagonist effect.

Outcome measurement of extensive implementation of antimicrobial stewardship in patients receiving intravenous antibiotics in a Japanese university hospital

PubMed Central

Niwa, T; Shinoda, Y; Suzuki, A; Ohmori, T; Yasuda, M; Ohta, H; Fukao, A; Kitaichi, K; Matsuura, K; Sugiyama, T; Murakami, N; Itoh, Y

2012-01-01

Background Antimicrobial stewardship has not always prevailed in a wide variety of medical institutions in Japan. Methods The infection control team was involved in the review of individual use of antibiotics in all inpatients (6348 and 6507 patients/year during the first and second annual interventions, respectively) receiving intravenous antibiotics, according to the published guidelines, consultation with physicians before prescription of antimicrobial agents and organisation of education programme on infection control for all medical staff. The outcomes of extensive implementation of antimicrobial stewardship were evaluated from the standpoint of antimicrobial use density, treatment duration, duration of hospital stay, occurrence of antimicrobial-resistant bacteria and medical expenses. Results Prolonged use of antibiotics over 2 weeks was significantly reduced after active implementation of antimicrobial stewardship (2.9% vs. 5.2%, p < 0.001). Significant reduction in the antimicrobial consumption was observed in the second-generation cephalosporins (p = 0.03), carbapenems (p = 0.003), aminoglycosides (p < 0.001), leading to a reduction in the cost of antibiotics by 11.7%. The appearance of methicillin-resistant Staphylococcus aureus and the proportion of Serratia marcescens to Gram-negative bacteria decreased significantly from 47.6% to 39.5% (p = 0.026) and from 3.7% to 2.0% (p = 0.026), respectively. Moreover, the mean hospital stay was shortened by 2.9 days after active implementation of antimicrobial stewardship. Conclusion Extensive implementation of antimicrobial stewardship led to a decrease in the inappropriate use of antibiotics, saving in medical expenses, reduction in the development of antimicrobial resistance and shortening of hospital stay. PMID:22846073

Starch-based Antimicrobial Films Incorporated with Lauric Acid and Chitosan

NASA Astrophysics Data System (ADS)

Salleh, E.; Muhamad, I. I.

2010-03-01

Antimicrobial (AM) packaging is one of the most promising active packaging systems. Starch-based film is considered an economical material for antimicrobial packaging. This study aimed at the development of food packaging based on wheat starch incorporated with lauric acid and chitosan as antimicrobial agents. The purpose is to restrain or inhibit the growth of spoilage and/or pathogenic microorganisms that are contaminating foods. The antimicrobial effect was tested on B. substilis and E. coli. Inhibition of bacterial growth was examined using two methods, i.e. zone of inhibition test on solid media and liquid culture test (optical density measurements). The control and AM films (incorporated with chitosan and lauric acid) were produced by casting method. From the observations, AM films exhibited inhibitory zones. Interestingly, a wide clear zone on solid media was observed for B. substilis growth inhibition whereas inhibition for E. coli was not as effective as B. substilis. From the liquid culture test, the AM films clearly demonstrated a better inhibition against B. substilis than E. coli.

Trachyspermum ammi (L.) sprague: chemical composition of essential oil and antimicrobial activities of respective fractions.

PubMed

Moein, Mahmoodreza R; Zomorodian, Kamiar; Pakshir, Keyvan; Yavari, Farnoosh; Motamedi, Marjan; Zarshenas, Mohammad M

2015-01-01

Resistance to antibacterial agents has become a serious problem for global health. The current study evaluated the antimicrobial activities of essential oil and respective fractions of Trachyspermum ammi (L.) Sprague. Seeds of the essential oil were extracted and fractionated using column chromatography. All fractions were then analyzed by gas chromatography/mass spectrometry. Antifungal and antibacterial activities of the oil and its fractions were assessed using microdilution method. Compounds γ-terpinene (48.07%), ρ-cymene (33.73%), and thymol (17.41%) were determined as major constituents. The effect of fraction II was better than total essential oil, fraction I, and standard thymol. The greater effect of fraction II compared to standard thymol showed the synergistic effects of the ingredients in this fraction. As this fraction and also total oil were effective on the studied microorganism, the combination of these products with current antimicrobial agents could be considered as new antimicrobial compounds in further investigations. © The Author(s) 2014.

Development of antimicrobial active packaging materials based on gluten proteins.

PubMed

Gómez-Heincke, Diana; Martínez, Inmaculada; Partal, Pedro; Guerrero, Antonio; Gallegos, Críspulo

2016-08-01

The incorporation of natural biocide agents into protein-based bioplastics, a source of biodegradable polymeric materials, manufactured by a thermo-mechanical method is a way to contribute to a sustainable food packaging industry. This study assesses the antimicrobial activity of 10 different biocides incorporated into wheat gluten-based bioplastics. The effect that formulation, processing, and further thermal treatments exert on the thermo-mechanical properties, water absorption characteristics and rheological behaviour of these materials is also studied. Bioplastics containing six of the 10 examined bioactive agents have demonstrated suitable antimicrobial activity at 37 °C after their incorporation into the bioplastic. Moreover, the essential oils are able to create an antimicrobial atmosphere within a Petri dish. Depending on the selected biocide, its addition may alter the bioplastics protein network in a different extent, which leads to materials exhibiting less water uptake and different rheological and thermo-mechanical behaviours. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.

Antimicrobial activity evaluation and comparison of methods of susceptibility for Klebsiella pneumoniae carbapenemase (KPC)-producing Enterobacter spp. isolates.

PubMed

Rechenchoski, Daniele Zendrini; Dambrozio, Angélica Marim Lopes; Vivan, Ana Carolina Polano; Schuroff, Paulo Alfonso; Burgos, Tatiane das Neves; Pelisson, Marsileni; Perugini, Marcia Regina Eches; Vespero, Eliana Carolina

The production of KPC (Klebsiella pneumoniae carbapenemase) is the major mechanism of resistance to carbapenem agents in enterobacterias. In this context, forty KPC-producing Enterobacter spp. clinical isolates were studied. It was evaluated the activity of antimicrobial agents: polymyxin B, tigecycline, ertapenem, imipenem and meropenem, and was performed a comparison of the methodologies used to determine the susceptibility: broth microdilution, Etest ® (bioMérieux), Vitek 2 ® automated system (bioMérieux) and disc diffusion. It was calculated the minimum inhibitory concentration (MIC) for each antimicrobial and polymyxin B showed the lowest concentrations for broth microdilution. Errors also were calculated among the techniques, tigecycline and ertapenem were the antibiotics with the largest and the lower number of discrepancies, respectively. Moreover, Vitek 2 ® automated system was the method most similar compared to the broth microdilution. Therefore, is important to evaluate the performance of new methods in comparison to the reference method, broth microdilution. Copyright © 2017 Sociedade Brasileira de Microbiologia. Published by Elsevier Editora Ltda. All rights reserved.

New 1,3,4-thiadiazole compounds including pyrazine moiety: Synthesis, structural properties and antimicrobial features

NASA Astrophysics Data System (ADS)

Gür, Mahmut; Şener, Nesrin; Muğlu, Halit; Çavuş, M. Serdar; Özkan, Osman Emre; Kandemirli, Fatma; Şener, İzzet

2017-07-01

In the study, some new 1,3,4-thiadiazole compounds were synthesized and we have reported identification of the structures by using UV-Vis, FT-IR, 1H NMR, 13C NMR and Mass spectroscopic methods. Antimicrobial activities of the compounds against three microorganisms, namely, Candida albicans ATCC 26555, Staphylococcus aureus ATCC 9144, and Escherichia coli ATCC 25922 were investigated by using disk diffusion method. These thiadiazoles exhibited an antimicrobial activity against Staphylococcus aureus and Candida albicans. The experimental data was supported by the quantum chemical calculations. Density functional theory (DFT) calculations were carried out to obtain the ground state optimized geometries of the molecules using the B3LYP, M06 and PBE1PBE methods with 3-21 g, 4-31 g, 6-311++g(2d,2p), cc-pvtz and cc-pvqz basis sets in the different combinations. Frontier molecular orbitals (FMOs) energies, band gap energies and some chemical reactivity parameters were calculated by using the aforementioned methods and basis sets, and the results were also compared with the experimental UV-Vis data.

Evaluation of wound healing, antioxidant and antimicrobial efficacy of Jasminum auriculatum Vahl. leaves

PubMed Central

Arun, Mittal; Satish, Sardana; Anima, Pandey

2016-01-01

Objective: To validate the ethno-therapeutic claim of the traditionally used plant Jasminum auriculatum (J. auriculatum) in skin diseases, by evaluating its wound healing potential along with its antioxidant and antimicrobial properties; so as to understand their role in wound healing. Materials and Methods: Excision and incision wound models were used to evaluate the wound healing activity on albino rats. The wound healing potential was assessed by measuring rate of wound contraction, epithelialization period, hydroxyproline content, skin breaking strength and histopathological parameters. Reference standard drug was Nitrofurazone ointment. The antioxidant activity was determined using 2, 2-diphenyl-1-picrylhydrazyl (DPPH) method. The antimicrobial activity was determined by agar well diffusion method and minimum inhibitory concentration by serial dilution method. Results: Higher rate of wound contraction (83.66±0.50% on 15th day), decrease in the period of epithelialization (17.83±1.6days), higher skin breaking strength (170.71±1.52g), higher collagen content and favourable histopathological changes revealed that topical application of ointment containing successive ethanolic extract (S.E.E) of J. auriculatum leaves has the most potent wound healing ability compared to control group in both the models studied. The DPPH radical scavenging activity of successive ethanolic extract was found to be 33.39µg/ml. Successive ethanolic extract was found to be most effective against Pseudomonas auregenosa having a zone of inhibition 16.65±0.6mm and the minimum inhibitory concentration was 0.78mg/ml. Conclusion: The data of this study indicate that successive ethanolic extract of the leaves exhibit potent wound healing, antioxidant and antimicrobial properties. This justifies the ethno-medicinal use of plant for the treatment of wound and microbial infections. PMID:27462552

In vitro antimicrobial activity of Pistacia lentiscus L. edible oil and phenolic extract.

PubMed

Mezni, F; Aouadhi, C; Khouja, M L; Khaldi, A; Maaroufi, A

2015-01-01

Pistacia lentiscus L. is known in some Tunisian forest area by its fixed oil used in traditional medicine as an antiseptic product. This investigation is the first to study the antimicrobial activity of P.lentiscus edible oil and its phenolic extract. Oil was extracted from fruits harvested from six provenances located in Tunisia. The antimicrobial activity was tested using disc diffusion assay and the broth dilution method. Kbouch and Sidi Zid oils were most efficient (p < 0.003) against, respectively, Staphylococcus aureus and Aspergillus niger with an inhibition zone of 9.33 mm. The phenolic extract had the largest spectrum of sensitive microorganisms. The minimum inhibitory concentration and minimum bactericidal concentration results showed that all strains were inhibited by both oil and extract.

Antimicrobial activity of some medicinal barks used in Peruvian Amazon.

PubMed

Kloucek, P; Svobodova, B; Polesny, Z; Langrova, I; Smrcek, S; Kokoska, L

2007-05-04

The aim of this study was to evaluate the antimicrobial activity of six barks traditionally used in Callería District (Ucayali Department, Peru) for treating conditions likely to be associated with microorganisms. Ethanol extracts of stem barks of Abuta grandifolia (Menispermaceae), Dipteryx micrantha (Leguminosae), Cordia alliodora (Boraginaceae), Naucleopsis glabra (Moraceae), Pterocarpus rohrii (Leguminosae), and root bark of Maytenus macrocarpa (Celastraceae) were tested against nine bacteria and one yeast using the broth microdilution method. All plants possessed significant antimicrobial effect, however, the extract of Naucleopsis glabra exhibited the strongest activity against Gram-positive bacteria (MICs ranging from 62.5 to 125 microg/ml), while the broadest spectrum of action was shown by the extract of Maytenus macrocarpa, which inhibited all the strains tested with MICs ranging from 125 to 250 microg/ml.

Optimization of synthesis process of thermally-responsive poly-n-isopropylacrylamide nanoparticles for controlled release of antimicrobial hydrophobic compounds

NASA Astrophysics Data System (ADS)

Hill, Laura E.; Gomes, Carmen L.

2014-12-01

The goal of this study was to develop an effective method to synthesize poly-n-isopropylacrylamide (PNIPAAM) nanoparticles with entrapped cinnamon bark extract (CBE) to improve its delivery to foodborne pathogens and control its release with temperature stimuli. CBE was used as a model for hydrophobic natural antimicrobials. A top-down procedure using crosslinked PNIPAAM was compared to a bottom-up procedure using NIPAAM monomer. Both processes relied on self-assembly of the molecules into micelles around the CBE at 40 °C. Processing conditions were compared including homogenization time of the polymer, hydration time prior to homogenization, lyophilization, and the effect of particle ultrafiltration. The top-down versus bottom-up synthesis methods yielded particles with significantly different characteristics, especially their release profiles and antimicrobial activities. The synthesis methods affected particle size, with the bottom-up procedure resulting in smaller (P < 0.05) diameters than the top-down procedure. The controlled release profile of CBE from nanoparticles was dependent on the release media temperature. A faster, burst release was observed at 40 °C and a slower, more sustained release was observed at lower temperatures. PNIPAAM particles containing CBE were analyzed for their antimicrobial activity against Salmonella enterica serovar Typhimurium LT2 and Listeria monocytogenes Scott A. The PNIPAAM particles synthesized via the top-down procedure had a much faster release, which led to a greater (P < 0.05) antimicrobial activity. Both of the top-down nanoparticles performed similarly, therefore the 7 min homogenization time nanoparticles would be the best for this application, as the process time is shorter and little improvement was seen by using a slightly longer homogenization.

The chemistry and applications of antimicrobial polymers: a state-of-the-art review.

PubMed

Kenawy, El-Refaie; Worley, S D; Broughton, Roy

2007-05-01

Microbial infection remains one of the most serious complications in several areas, particularly in medical devices, drugs, health care and hygienic applications, water purification systems, hospital and dental surgery equipment, textiles, food packaging, and food storage. Antimicrobials gain interest from both academic research and industry due to their potential to provide quality and safety benefits to many materials. However, low molecular weight antimicrobial agents suffer from many disadvantages, such as toxicity to the environment and short-term antimicrobial ability. To overcome problems associated with the low molecular weight antimicrobial agents, antimicrobial functional groups can be introduced into polymer molecules. The use of antimicrobial polymers offers promise for enhancing the efficacy of some existing antimicrobial agents and minimizing the environmental problems accompanying conventional antimicrobial agents by reducing the residual toxicity of the agents, increasing their efficiency and selectivity, and prolonging the lifetime of the antimicrobial agents. Research concerning the development of antimicrobial polymers represents a great a challenge for both the academic world and industry. This article reviews the state of the art of antimicrobial polymers primarily since the last comprehensive review by one of the authors in 1996. In particular, it discusses the requirements of antimicrobial polymers, factors affecting the antimicrobial activities, methods of synthesizing antimicrobial polymers, major fields of applications, and future and perspectives in the field of antimicrobial polymers.

Antimicrobial activity of crude epicarp and seed extracts from mature avocado fruit (Persea americana) of three cultivars.

PubMed

Raymond Chia, Teck Wah; Dykes, Gary A

2010-07-01

The epicarp and seed of Persea Americana Mill. var. Hass (Lauraceae), Persea Americana Mill. var. Shepard, and Persea americana Mill. var Fuerte cultivars of mature avocados (n = 3) were ground separately and extracted with both absolute ethanol and distilled water. Extracts were analyzed for antimicrobial activity using the microtiter broth microdilution assay against four Gram-positive bacteria, six Gram-negative bacteria, and one yeast. Antimicrobial activity against two molds was determined by the hole plate method. The ethanol extracts showed antimicrobial activity (104.2-416.7 microg/mL) toward both Gram-positive and Gram-negative bacteria (except Escherichia coli), while inhibition of the water extracts was only observed for Listeria monocytogenes (93.8-375.0 microg/mL) and Staphylococcus epidermidis (354.2 microg/mL). The minimum concentration required to inhibit Zygosaccharomyces bailii was 500 microg/mL for the ethanol extracts, while no inhibition was observed for the water extracts. No inhibition by either ethanol or water extracts was observed against Penicillium spp. and Aspergillus flavus.

Evaluation of a Microbial Sensor as a Tool for Antimicrobial Activity Test of Cosmetic Preservatives.

PubMed

Gomyo, Hideyuki; Ookawa, Masaki; Oshibuchi, Kota; Sugamura, Yuriko; Hosokawa, Masahito; Shionoiri, Nozomi; Maeda, Yoshiaki; Matsunaga, Tadashi; Tanaka, Tsuyoshi

2015-01-01

For high-throughput screening of novel cosmetic preservatives, a rapid and simple assay to evaluate the antimicrobial activities should be developed because the conventional agar dilution method is time-consuming and labor-intensive. To address this issue, we evaluated a microbial sensor as a tool for rapid antimicrobial activity testing. The sensor consists of an oxygen electrode and a filter membrane that holds the test microorganisms, Staphylococcus aureus and Candida albicans. The antimicrobial activity of the tested cosmetic preservative was evaluated by measuring the current increases corresponding to the decreases in oxygen consumption in the microbial respiration. The current increases detected by the sensor showed positive correlation to the concentrations of two commercially used preservatives, chlorphenesin and 2-phenoxyethanol. The same tendency was also observed when a model cosmetic product was used as a preservative solvent, indicating the feasibility in practical use. Furthermore, the microbial sensor and microfluidic flow-cell was assembled to achieve sequential measurements. The sensor system presented in this study could be useful in large-scale screening experiments.

[The study of antimicrobial properties of silver nanoparticles in the form of a colloidal solution in the matrix of finely dispersed silica].

PubMed

Korchak, G I; Surmasheva, E V; Mikhienkova, A I; Nikonova, N A; Romanenko, L I; Oliĭnyk, Z A; Gorval', A K; Rosada, M A

2012-01-01

In the experimental study obtained with chemical method colloid solution of nanoparticles (NPs) of silver (Ag) and a composite on his base in the matrix of finely dispersed silica with particle size of 8-12 nm and NPs concentration in basic solution of 0,0016% (0,016 mg/cm3) were established to exhibit high antimicrobial activity against the test organisms: E. coli, P. aeruginosa, S. Aureus and C. Albicans, which depended on a set of factors. Antibacterial properties of tissue impregnated with Ag-NPs were studied. As stabilizing substances a mixture of surface-active substance sodium dodecyl sulfate and polymer polyvinylpyrrolidone was used Before the beginning of the study effective neutralizer was tailored. Times of preservation of antimicrobial activity of test samples have been established, and also their stability throughout long term of supervision (24 months) has been shown. Effect of organic pollution on antimicrobal activity of the samples has been studied. Based on obtained results the algorithm of the study of antimicrobial properties of nanopreparations has been elaborated.

Effect of glycerol and zinc oxide addition on antibacterial activity of biodegradable bioplastics from chitosan-kepok banana peel starch

NASA Astrophysics Data System (ADS)

Agustin, Y. E.; Padmawijaya, K. S.

2017-07-01

Bioplastic is a biopolymer plastic that can be degraded easily by microorganisms so it can be used as alternative replaced commercial plastic. This research aims to study the effects of additive (glycerol and zinc oxide) addition in the characteristic of antimicrobial activity and biodegradability bioplastic from chitosan and Kepok banana peel starch. In this research, bioplastics were synthesized by chitosan as the backbone and antimicrobial, Kepok banana peel starch as filler, glycerol as plasticizer, also ZnO as an amplifier. Bioplastics were characterized their antimicrobial activity using agar diffusion method (zone inhibition assay) and biodegradability test using microbe (EM4). The result showed the optimum composition of bioplastic is kitosan 4 - 30% starch - 5 mL glycerol - 5% ZnO gives the good antimicrobial activity towards gram positive and gram negative bacteria, and this bioplastic will be degraded within an hour and 12 min. Thus, this bioplastics may have potential to be use for food packaging by having biodegradable properties and also inhibit bacterial growth.

Antibacterial activity and composition of essential oils from Pelargonium graveolens L'Her and Vitex agnus-castus L

PubMed Central

Ghannadi, A; Bagherinejad, MR; Abedi, D; Jalali, M; Absalan, B; Sadeghi, N

2012-01-01

Background and Objectives Essential oils are volatile compounds that have been used since Middle Ages as antimicrobial, anti-inflammatory, sedative, local anesthetic and food flavoring agents. In the current study, essential oils of Pelargonium graveolens L'Her and Vitex agnus-castus L. were analyzed for their antibacterial activities. Materials and Methods The chemical compositions of essential oils were characterized by GC-MS. Disc diffusion method was used to study antimicrobial activity. Results and Conclusion Inhibition zones showed that the essential oils of the two plants were active against all of the studied bacteria (except Listeria monocytogenes). The susceptibility of the strains changed with the dilution of essential oils in DMSO. The pure essential oils showed the most extensive inhibition zones and they were very effective antimicrobial compounds compared to chloramphenicol and amoxicillin. The most susceptible strain against these two essential oils was Staphylococcus aureus. It seems that β-citronellol is a prominent part of P. graveolens volatile oil and caryophyllene oxide is a famous and important part of V. agnus-castus volatile oil and their probable synergistic effect with other constituents are responsible for the antibacterial effects of these oils. However further studies must be performed to confirm the safety of these oils for use as antimicrobial agents and natural preservatives in different products. PMID:23205247

IN VITRO ANTIMICROBIAL SCREENING OF AQUILARIA AGALLOCHA ROOTS.

PubMed

Canlı, Kerem; Yetgin, Ali; Akata, Ilgaz; Altuner, Ergin Murat

2016-01-01

It was previously shown that some parts of Aquilaria agallocha , which is commonly known as oud or oodh, such as roots have been used as a traditional medical herbal in different countries. In Turkey A. agallocha is one of the ingredients while preparing famous Mesir paste, which was invented as a medicinal paste and used from the Ottoman period to now at least for 500 years. The identification the in vitro antimicrobial activity of ethanol extract of A. agallocha roots is main purpose of this analysis. By using 17 bacteria and 1 fungi, which include Bacillus, Candida, Enterobacter, Enterococcus, Escherichia, Klebsiella, Listeria, Pseudomonas, Salmonella and Staphylococcus genera, the activity of A. agallocha root extracts were analysed by the help of the disk diffusion method, that is one of the methods commonly used to determine antimicrobial activities. As a result of the study it was observed that ethanol extracts of A. agallocha roots have a clear antimicrobial activity against nearly all microorganism used in the study, but only two bacteria namely E. coli ATCC 25922 and S. typhimurium SL 1344. According to the disk diffusion test results it may be possible to propose that A. agallocha roots should have a medicinal uses especially against E. faecium , L. monocytogenes ATCC 7644, B. subtilis DSMZ 1971, C. albicans DSMZ 1386, S. epidermidis DSMZ 20044 and S. aureus ATCC 25923.

Comparative Study of Essential Oils Extracted from Egyptian Basil Leaves (Ocimum basilicum L.) Using Hydro-Distillation and Solvent-Free Microwave Extraction.

PubMed

Chenni, Mohammed; El Abed, Douniazad; Rakotomanomana, Njara; Fernandez, Xavier; Chemat, Farid

2016-01-19

Solvent-free microwave extraction (SFME) and conventional hydro-distillation (HD) were used for the extraction of essential oils (EOs) from Egyptian sweet basil (Ocimum basilicum L.) leaves. The two resulting EOs were compared with regards to their chemical composition, antioxidant, and antimicrobial activities. The EO analyzed by GC and GC-MS, presented 65 compounds constituting 99.3% and 99.0% of the total oils obtained by SFME and HD, respectively. The main components of both oils were linalool (43.5% SFME; 48.4% HD), followed by methyl chavicol (13.3% SFME; 14.3% HD) and 1,8-cineole (6.8% SFME; 7.3% HD). Their antioxidant activity were studied with the 2,2-diphenyl-1-picrylhydrazyl (DPPH(•)) radical scavenging method. The heating conditions effect was evaluated by the determination of the Total Polar Materials (TPM) content. The antimicrobial activity was investigated against five microorganisms: two Gram-positive bacteria, Staphylococcus aureus and Bacillus subtilis, two Gram-negative bacteria, Escherichia coli and Pseudomonas aeruginosa, and one yeast, Candida albicans. Both EOs showed high antimicrobial, but weak antioxidant, activities. The results indicated that the SFME method may be a better alternative for the extraction of EO from O. basilicum since it could be considered as providing a richer source of natural antioxidants, as well as strong antimicrobial agents for food preservation.

Antimicrobial activity and mechanism of action of a novel cationic α-helical octadecapeptide derived from α-amylase of rice.

PubMed

Taniguchi, Masayuki; Ochiai, Akihito; Takahashi, Kiyoshi; Nakamichi, Shun-ichi; Nomoto, Takafumi; Saitoh, Eiichi; Kato, Tetsuo; Tanaka, Takaaki

2015-03-01

AmyI-1-18, an octadecapeptide derived from α-amylase (AmyI-1) of rice (Oryza sativa L. japonica), is a novel cationic α-helical antimicrobial peptide (AMP) that contains two lysine and two arginine residues. The antimicrobial activity of AmyI-1-18 against human pathogens was quantitatively evaluated using a chemiluminescence method that measures ATP derived from viable cells. Of the ten kinds of human pathogens, AmyI-1-18 exhibited antimicrobial activity against nine. Its 50% growth-inhibitory concentrations (ICs50 ) against Porphyromonas gingivalis, Propionibacterium acnes, Pseudomonas aeruginosa, Candida albicans, and Streptococcus mutans were 13, 19, 50, 64, and 77 μM, respectively. AmyI-1-18 had little or no hemolytic activity even at 500 μM, and showed negligible cytotoxicity up to 1200 μM. The degree of 3,3'-dipropylthiadicarbocyanine iodide release from P. gingivalis cells induced by the addition of AmyI-1-18 was significantly lower than that induced by the addition of melittin. Flow cytometric analysis showed that the percentages of P. aeruginosa, S. mutans, and C. albicans cells stained with propidium iodide (PI), a DNA-intercalating dye, were 89%, 43%, and 3%, respectively, when AmyI-1-18 was added at a concentration equal to its 4×IC50 . Therefore, the antimicrobial activity of AmyI-1-18 against P. aeruginosa and S. mutans appears to be mainly attributable to its membrane-disrupting activity. In contrast, its antimicrobial activity against P. gingivalis and C. albicans most likely depends upon interactions with intracellular targets other than their cell membranes. Collectively, these results indicate that AmyI-1-18 is useful as a safe and potent AMP against the pathogens described above in many fields of healthcare. © 2015 Wiley Periodicals, Inc.

Comparative study of volatile oil content and antimicrobial activity of pecan cultivars growing in Egypt.

PubMed

El Hawary, Seham S; Zaghloul, Soumaya S; El Halawany, Ali M; El Bishbishy, Mahitab H

2013-11-01

The volatile oils obtained from the leaves of four pecan cultivars growing in Egypt were evaluated for their chemical composition and antimicrobial activity. The selected cultivars (cv.) were Carya illinoinensis (Wangneh.) K. Koch. cv. Wichita, C. illinoinensis cv. Western Schley, C. illinoinensis cv. Cherokee, and C. illinoinensis cv. Sioux. The gas chromatography-mass spectrometry analyses revealed that the volatile oils from samples of the different cultivars differ in composition and percentage of their components. β-Curcumene was found as the major constituent of the cv. Wichita oil, whereas germacrene D was the major component of cv. Sioux, cv. Cherokee, and cv. Western Schley. The antimicrobial activity was assayed using the Kirby-Bauer Method by measuring the zone of inhibition of growth. All volatile oils displayed an antimicrobial activity against the tested bacterial strains. On the other hand, only the volatile oil of cv. Wichita showed an antifungal effect on Aspergillus flavus. This work has identified candidates of volatile oils for future in vivo studies to develop antibiotic substitutes for the diminution of human and animal pathogenic bacteria. Nevertheless, the variations of the volatile oil components and antimicrobial potencies of the different studied cultivars, necessitate identifying the cultivars used in future studies.

Anti-microbial activity and composition of manuka and portobello honey.

PubMed

Schneider, Monika; Coyle, Shirley; Warnock, Mary; Gow, Iain; Fyfe, Lorna

2013-08-01

Recently renewed interest in the therapeutic properties of honey has led to the search for new antimicrobial honeys. This study was undertaken to assess the antimicrobial activity and composition of a locally produced Portobello honey (PBH) on three bacteria known to infect wounds. Manuka honey (MH) was used for comparative purposes. Broth culture and agar disc diffusion assays were used to investigate the antimicrobial properties of honey. The honeys were tested at four concentrations: 75%, 50%, 10% and 1% (v/v) and compared with an untreated control. The composition of honey was determined by measuring: polyphenol content by Folin Ciocalteau method, antioxidant capacity by ferric ion reducing power assay, hydrogen peroxide (H2 O2 ) by catalase test, pH and sugar content by pH strips and refractometer, respectively. Both honeys at 75% and 50% inhibited the majority of the three bacteria tested. 10% PBH exhibited antimicrobial activity to the lesser extent than 10% MH. The difference was very significant (p ≤ 0.001). Both honeys were acidic with pH 4, and both produced H2 O2 . The sugar content of PBH was higher than MH, but the difference was not significant. The MH had significantly higher levels of the polyphenols and antioxidant activity than PBH. Copyright © 2012 John Wiley & Sons, Ltd.

Challenges with gonorrhea in the era of multi-drug and extensively drug resistance – are we on the right track?

PubMed Central

Unemo, Magnus; Golparian, Daniel; Shafer, William M

2015-01-01

Neisseria gonorrhoeae has retained antimicrobial resistance to drugs previously recommended for first-line empiric treatment of gonorrhea, and resistance to ceftriaxone, the last option for monotherapy, is evolving. Crucial actions to combat this developing situation include implementing response plans; considering use of dual antimicrobial regimens; enhancing surveillance of gonorrhea, gonococcal antimicrobial resistance, treatment failures and antimicrobial use/misuse and improving prevention, early diagnosis, contact tracing and treatment. The ways forward also include an intensified research to identify novel antimicrobial resistance determinants and develop and evaluate appropriate use of molecular antimicrobial resistance testing, ideally point-of-care and with simultaneous detection of gonococci, to supplement culture-based methods and ideally guide tailored treatment. It is crucial with an enhanced understanding of the dynamics of the national and international emergence, transmission and evolution of antimicrobial-resistant gonococcal strains. Genome sequencing combined with epidemiological metadata will detail these issues and might also revolutionize the molecular antimicrobial resistance testing. Ultimately, novel antimicrobials are essential and some antimicrobials in development have shown potent in vitro activity against gonococci. Several of these antimicrobials deserve further attention for potential future treatment of gonorrhea. PMID:24702589

Evaluation of antimicrobial and anti-inflammatory activities of seed extracts from six Nigella species.

PubMed

Landa, Premysl; Marsik, Petr; Havlik, Jaroslav; Kloucek, Pavel; Vanek, Tomas; Kokoska, Ladislav

2009-04-01

Seed extracts from six species of the genus Nigella (Family Ranunculaceae)-Nigella arvensis, Nigella damascena, Nigella hispanica, Nigella nigellastrum, Nigella orientalis, and Nigella sativa-obtained by successive extraction with n-hexane, chloroform, and methanol, were tested for their antimicrobial activity against 10 strains of pathogenic bacteria and yeast using the microdilution method as well as for anti-inflammatory properties by in vitro cyclooxygenase (COX)-1 and COX-2 assay. Chemical characterization of active extracts was carried out including free and fixed fatty acid analysis. Comparison of antimicrobial activity showed that N. arvensis chloroform extract was the most potent among all species tested, inhibiting Gram-positive bacterial and yeast strains with minimum inhibitory concentration (MIC) values ranging from 0.25 to 1 mg/mL. With the exception of selective inhibitory action of n-hexane extract of N. orientalis on growth of Bacteroides fragilis (MIC = 0.5 mg/mL), we observed no antimicrobial activity for other Nigella species. Anti-inflammatory screening revealed that N. sativa, N. orientalis, N. hispanica, N. arvensis n-hexane, and N. hispanica chloroform extracts had strong inhibitory activity (more than 80%) on COX-1 and N. orientalis, N. arvensis, and N. hispanica n-hexane extracts were most effective against COX-2, when the concentration of extracts was 100 microg/mL in both COX assays. In conclusion, N. arvensis, N. orientalis, and N. hispanica seeds, for the first time examined for antimicrobial and anti-inflammatory effects, revealed their significant activity in one or both assays.

Antimicrobial Activity and Brine Shrimp Lethality Bioassay of the Leaves Extract of Dillenia indica Linn

PubMed Central

Apu, AS; Muhit, MA; Tareq, SM; Pathan, AH; Jamaluddin, ATM; Ahmed, M

2010-01-01

The crude methanolic extract of Dillenia indica Linn. (Dilleniaceae) leaves has been investigated for the evaluation of antimicrobial and cytotoxic activities. Organic solvent (n-hexane, carbon tetrachloride and chloroform) fractions of methanolic extract and methanolic fraction (aqueous) were screened for their antimicrobial activity by disc diffusion method. Besides, the fractions were screened for cytotoxic activity using brine shrimp (Artemia salina) lethality bioassay. Among the four fractions tested, n-hexane, carbon tetrachloride, and chloroform fractions showed moderate antibacterial and antifungal activity compared to standard antibiotic, kanamycin. The average zone of inhibition was ranged from 6 to 8 mm at a concentration of 400 µg/disc. But the aqueous fraction was found to be insensitive to microbial growth. Compared to vincristine sulfate (with LC50 of 0.52 µg/ ml), n-hexane and chloroform fractions demonstrated a significant cytotoxic activity (having LC50 of 1.94 µg/ml and 2.13 µg/ml, respectively). The LC50 values of the carbon tetrachloride and aqueous fraction were 4.46 µg/ml and 5.13 µg/ ml, respectively. The study confirms the moderate antimicrobial and potent cytotoxic activities of Dillenia indica leaves extract and therefore demands the isolation of active principles and thorough bioassay. PMID:21331191

Isolation, Purification and Characterization of Antimicrobial Agent Antagonistic to Escherichia coli ATCC 10536 Produced by Bacillus pumilus SAFR-032 Isolated from the Soil of Unaizah, Al Qassim Province of Saudi Arabia.

PubMed

S Alanazi, Abdurrahman; Qureshi, Kamal Ahmad; Elhassan, Gamal Osman; I El-Agamy, Elsayed

Escherichia coli is one of the most common pathogenic bacteria, which cause urinary tract infections in infants as well as in adult human beings. Due to the emergence of antibiotic resistance in E. coli, there is a great demand of new antimicrobial agent for the treatment of infections caused by such E. coli. This study aims to isolate, identify and characterize the native soil-bacterial strains predominate in the soil of Unaizah city, which produce antimicrobial agent antagonistic to E. coli ATCC 10536, followed by isolation, purification and characterization of antimicrobial agent. Pour plate, spread plate and 16S rRNA sequence analysis methods were followed for the isolation and identification of soil bacteria. Ammonium sulphate and dialysis (MWCO-8 KD) methods were followed for the isolation and partial purification of antimicrobial agent from the cell free broths. The characterization of antimicrobial agent was carried out by determining the minimum inhibitory concentration and effects of temperature and pH on the antimicrobial stability. Out of the twenty five soil samples, only one soil-bacterial strain was found to produce antimicrobial agent antagonistic to E. coli ATCC 10536. The isolated soil bacterium was identified as Bacillus pumilus SAFR-032. The soil isolate was characterized and results suggest that 30°C temperature and pH 7.0 were the optimum growth parameters and soybean casein digest broth was the best fermentation medium, whereas the highest production of antimicrobial agent was at 35°C temperature, pH 7.0, shaking at 150-220 rpm and at 60th h of incubation. The maximum yield of antimicrobial agent was obtained at 60% of (NH 4) 2SO 4. The results of characterization of antimicrobial agent suggest that the maximum and minimum antimicrobial activities were at pH 3.0 and 8.0, respectively, whereas antimicrobial activity was unaffected by temperature. The antimicrobial agent was highly stable at varying range of temperature 50-120°C. Minimum inhibitory concentration of antimicrobial agent was found to be 64 μg mL -1. In conclusion, this study might be a great endeavor for the healthcare industry in order to treatment of different infections caused by E. coli and that warrants further investigations to fully standardized and establish the antimicrobial profile of effect(s) of this isolate.

Facile fabrication and characterization of chitosan-based zinc oxide nanoparticles and evaluation of their antimicrobial and antibiofilm activity

NASA Astrophysics Data System (ADS)

Dhillon, Gurpreet Singh; Kaur, Surinder; Brar, Satinder Kaur

2014-06-01

The present investigation deals with the facile synthesis and characterization of chitosan (CTS)-based zinc oxide (ZnO) nanoparticles (NPs) and their antimicrobial activities against pathogenic microorganisms. ZnO-CTS NPs were synthesized through two different methods: nano spray drying and precipitation, using various organic compounds (citric acid, glycerol, starch and whey powder) as stabilizers. Both the synthesis methods were simple and were devoid of any chemical usage. The detailed characterization of the NPs was carried out using UV-Vis spectroscopy, dynamic light scattering particle size analysis, zeta potential measurements and scanning electron microscopy, which confirmed the fabrication of NPs with different shapes and sizes. Antimicrobial assay of synthesized ZnO-CTS NPs was carried out against different pathogenic microbial strains ( Candida albicans, Micrococcus luteus and Staphylococcus aureus). The significant ( p < 0.05) inhibition of growth was observed for both M. luteus and S. aureus with ZnO-CTS NPs (with a concentration ranging from 0.625 to 0.156 mg/ml) as compared to control treatment. ZnO-CTS NPs also showed significant biofilm inhibition activity ( p < 0.05) against M. luteus and S. aureus. The study demonstrated the potential of ZnO-CTS NPs as antimicrobial and antibiofilm agents.

Phytochemical screening and study of antioxidant, antimicrobial, antidiabetic, anti-inflammatory and analgesic activities of extracts from stem wood of Pterocarpus marsupium Roxburgh.

PubMed

Pant, Dipak Raj; Pant, Narayan Dutt; Saru, Dil Bahadur; Yadav, Uday Narayan; Khanal, Dharma Prasad

2017-01-01

The main aims of the study were to evaluate the phytochemical constituents and to study the antioxidant, antimicrobial, antidiabetic, anti-inflammatory, and analgesic activities of extracts from stem wood of Pterocarpus marsupium . Ethanol, acetone and isopropyl alcohol (IPA) (1:1) extracts of stem wood of P. marsupium were subjected to phytochemical screening and analysis of biological activities from August 2015 to January 2016. The antioxidant assay was carried out using 2, 2-diphenyl-1-picrylhydrazyl scavenging method, antimicrobial activity testing by cup diffusion method, antidiabetic test evaluation by oral glucose tolerance test in mice, anti-inflammatory effect was evaluated by hind paw edema method in mice and analgesic test evaluation by a chemical writhing method in mice. The results of the study revealed that P. marsupium is a source of various phytoconstituents such as alkaloids, glycosides, saponins, tannins, proteins, carbohydrates, cardiac glycosides, flavonoids, and terpenoids. Both the acetone and IPA extract as well as the ethanol extract of stem wood of P. marsupium exhibited a dose-dependent antioxidant activity. Acetone and IPA extract showed antibacterial activity against Gram-positive bacteria, while the ethanolic extract was found to possess antidiabetic activity. The antidiabetic activity of the extract was found to be time and dose-dependent. Similarly, the acetone and IPA extract was found to have anti-inflammatory activity, which was also time and dose-dependent. Furthermore, the ethanolic extract showed analgesic activity, which was dose-dependent. The ethanolic extract was found to be nontoxic. Thus, this study laid sufficient background for the further research on extracts from stem wood of P. marsupium for identification, subsequent purification and isolation of compounds having antibacterial, antidiabetic, anti-inflammatory, and analgesic activities.

Evaluation of metal concentration and antioxidant, antimicrobial, and anticancer potentials of two edible mushrooms Lactarius deliciosus and Macrolepiota procera.

PubMed

Kosanić, Marijana; Ranković, Branislav; Rančić, Aleksandar; Stanojković, Tatjana

2016-07-01

This study is designed for the determination of metal concentrations, antioxidant, antimicrobial, and anticancer potential of two edible mushrooms Lactarius deliciosus and Macrolepiota procera. Concentrations of nine metals are determined and all metals are present in the allowable concentrations in the tested mushrooms except Cd in M. procera. Antioxidant activity was evaluated by free radical scavenging and reducing power. M. procera extract had more potent free radical scavenging activity (IC 50 =311.40 μg/mL) than L. deliciosus extract. Moreover, the tested extracts had effective reducing power. The total content of phenol in the extracts was examined using Folin-Ciocalteu reagent and obtained values expressed as pyrocatechol equivalents. Further, the antimicrobial potential was determined with a microdilution method on 15 microorganisms. Among the tested species, extract of L. deliciosus showed a better antimicrobial activity with minimum inhibitory concentration values ranging from 2.5 mg/mL to 20 mg/mL. Finally, the cytotoxic activity was tested using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide method on human epithelial carcinoma HeLa cells, human lung carcinoma A549 cells, and human colon carcinoma LS174 cells. Extract of both mushrooms expressed similar cytotoxic activity with IC 50 values ranging from 19.01 μg/mL to 80.27 μg/mL. Copyright © 2016. Published by Elsevier B.V.

Sesquiterpene lactones from Gynoxys verrucosa and their anti-MRSA activity.

PubMed

Ordóñez, Paola E; Quave, Cassandra L; Reynolds, William F; Varughese, Kottayil I; Berry, Brian; Breen, Philip J; Malagón, Omar; Smeltzer, Mark S; Compadre, Cesar M

2011-09-02

Because of its virulence and antibiotic resistance, Staphylococcus aureus is a more formidable pathogen now than at any time since the pre-antibiotic era. In an effort to identify and develop novel antimicrobial agents with activity against this pathogen, we have examined Gynoxys verrucosa Wedd (Asteraceae), an herb used in traditional medicine in southern Ecuador for the treatment and healing of wounds. The sesquiterpene lactones leucodine (1) and dehydroleucodine (2) were extracted and purified from the aerial parts of Gynoxys verrucosa, and their structure was elucidated by spectroscopic methods and single-crystal X-ray analysis. The in vitro anti-microbial activity of Gynoxys verrucosa extracts and its purified constituents was determined against six clinical isolates including Staphylococcus aureus and Staphylococcus epidermidis strains with different drug-resistance profiles, using the microtiter broth method. Compound 1 has very low activity, while compound 2 has moderate activity with MIC(50)s between 49 and 195 μg/mL. The extract of Gynoxys verrucosa has weak activity with MIC(50)s between 908 and 3290 μg/mL. We are reporting the full assignment of the (1)H NMR and (13)C NMR of both compounds, and the crystal structure of compound 2, for the first time. Moreover, the fact that compound 2 has antimicrobial activity and compound 1 does not, demonstrates that the exocyclic conjugated methylene in the lactone ring is essential for the antimicrobial activity of these sesquiterpene lactones. However, the weak activity observed for the plant extracts, does not explain the use of Gynoxys verrucosa in traditional medicine for the treatment of wounds and skin infections. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

The Antimicrobial Activities of Extract and Compounds Isolated from Brillantaisia lamium

PubMed Central

Tamokou, Jean De Dieu; Kuiate, Jules Roger; Tene, Mathieu; Kenla Nwemeguela, Timothée Julbelin; Tane, Pierre

2011-01-01

Background: Brillantaisia lamium is an erect branched herb, which grows to a height of 1.50 m in moist tropical areas, both in full sun and partial shade. In , the aerial part of this plant is used in the treatment of various microbial infections such as skin diseases and infections of urinary tract. The aim of this study was to evaluate the antimicrobial activities of CH2Cl2: MeOH (1:1) extract, fractions and compounds from the aerial part of B. lamium. Methods: The plant was dried and extracted by maceration in CH2Cl2: MeOH (1:1 v/v). Structures of the compounds from the CH2Cl2: MeOH (1:1) soluble fraction were determined by spectroscopic methods and compared with published data. The broth micro dilution method was used to evaluate the antimicrobial activities against bacteria and fungal species. Results: Four known compounds: aurantiamide acetate (1), lupeol (2), lespedin (3), sitosterol 3-O-β-D-glucopyranoside (4) and a mixture of sterols: campesterol (5), stigmasterol (6) and β-sitosterol (7) were isolated from CH2Cl2: MeOH (1:1) extract of B. lamium aerial parts. The crude extract, fractions and isolated compounds exhibited both antibacterial and antifungal activities that varied with microorganism (MIC=6.25 – 1000 µg/ml). Compound 3 was the most active (MIC=6.25 – 100 µg/ml) while Staphylococcus aureus, Enterococcus faecalis, Candida tropicalis and Cryptococcus neoformans were the most sensitive to all the tested compounds. Conclusion: The overall results of this study indicate that the CH2Cl2: MeOH (1:1) extract and some of isolated compounds have interesting antimicrobial properties and can be used for the treatment of fungal and bacterial infections. PMID:23365474

Gas Chromatography, GC/Mass Analysis and Bioactivity of Essential Oil from Aerial Parts of Ferulago trifida: Antimicrobial, Antioxidant, AChE Inhibitory, General Toxicity, MTT Assay and Larvicidal Activities.

PubMed

Tavakoli, Saeed; Vatandoost, Hassan; Zeidabadinezhad, Reza; Hajiaghaee, Reza; Hadjiakhoondi, Abbas; Abai, Mohammad Reza; Yassa, Narguess

2017-09-01

We aimed to investigate different biological properties of aerial parts essential oil of Ferulago trifida Boiss and larvicidal activity of its volatile oils from all parts of plant. Essential oil was prepared by steam distillation and analyzed by Gas chromatography and GC/Mass. Antioxidant, antimicrobial, cytotoxic effects and AChE inhibitory of the oil were investigated using DPPH, disk diffusion method, MTT assay and Ellman methods. Larvicidal activity of F. trifida essential oil against malaria vector Anopheles stephensi was carried out according to the method described by WHO. In GC and GC/MS analysis, 58 compounds were identified in the aerial parts essential oil, of which E-verbenol (9.66%), isobutyl acetate (25.73%) and E-β-caryophyllene (8.68%) were main compounds. The oil showed (IC 50 = 111.2μg/ml) in DPPH and IC 50 = 21.5 mg/ml in the investigation of AChE inhibitory. Furthermore, the oil demonstrated toxicity with (LD 50 = 1.1μg/ml) in brine shrimp lethality test and with (IC 50 = 22.0, 25.0 and 42.55 μg/ml) on three cancerous cell lines (MCF-7, A-549 and HT-29) respectively. LC 50 of stem, root, aerial parts, fruits, and flowers essential oils against larvae of An. stephensi were equal with 10.46, 22.27, 20.50, 31.93 and 79.87ppm respectively. In antimicrobial activities, essential oil was effective on all specimens except Escherichia coli , Aspergillus niger and Candida albicans. The essential oil showed moderate antioxidant activity, strong antimicrobial properties and good toxic effect in brine shrimp test and MTT assay on three cancerous cell lines.

In vitro antimicrobial activity of ten medicinal plants against clinical isolates of oral cancer cases.

PubMed

Panghal, Manju; Kaushal, Vivek; Yadav, Jaya P

2011-05-20

Suppression of immune system in treated cancer patients may lead to secondary infections that obviate the need of antibiotics. In the present study, an attempt was made to understand the occurrence of secondary infections in immuno-suppressed patients along with herbal control of these infections with the following objectives to: (a) isolate the microbial species from the treated oral cancer patients along with the estimation of absolute neutrophile counts of patients (b) assess the in vitro antimicrobial activity medicinal plants against the above clinical isolates. Blood and oral swab cultures were taken from 40 oral cancer patients undergoing treatment in the radiotherapy unit of Regional Cancer Institute, Pt. B.D.S. Health University,Rohtak, Haryana. Clinical isolates were identified by following general microbiological, staining and biochemical methods. The absolute neutrophile counts were done by following the standard methods. The medicinal plants selected for antimicrobial activity analysis were Asphodelus tenuifolius Cav., Asparagus racemosus Willd., Balanites aegyptiaca L., Cestrum diurnum L., Cordia dichotoma G. Forst, Eclipta alba L., Murraya koenigii (L.) Spreng. , Pedalium murex L., Ricinus communis L. and Trigonella foenum graecum L. The antimicrobial efficacy of medicinal plants was evaluated by modified Kirby-Bauer disc diffusion method. MIC and MFC were investigated by serial two fold microbroth dilution method. Prevalent bacterial pathogens isolated were Staphylococcus aureus (23.2%), Escherichia coli (15.62%), Staphylococcus epidermidis (12.5%), Pseudomonas aeruginosa (9.37%), Klebsiella pneumonia (7.81%), Proteus mirabilis (3.6%), Proteus vulgaris (4.2%) and the fungal pathogens were Candida albicans (14.6%), Aspergillus fumigatus (9.37%). Out of 40 cases, 35 (87.5%) were observed as neutropenic. Eight medicinal plants (A. tenuifolius, A. racemosus, B. aegyptiaca, E. alba, M. koenigii, P. murex R. communis and T. foenum graecum) showed significant antimicrobial activity (P < .05) against most of the isolates. The MIC and MFC values were ranged from 31 to 500 μg/ml. P. aeruginosa was observed highest susceptible bacteria (46.6%) on the basis of susceptible index. It can be concluded that treated oral cancer patients were neutropenic and prone to secondary infection of microbes. The medicinal plant can prove as effective antimicrobial agent to check the secondary infections in treated cancer patients.

Tetracycline improved the efficiency of other antimicrobials against Gram-negative multidrug-resistant bacteria.

PubMed

Mawabo, Isabelle K; Noumedem, Jaurès A K; Kuiate, Jules R; Kuete, Victor

2015-01-01

Treatment of infectious diseases with antimicrobials constituted a great achievement in the history of medicine. Unfortunately, the emergence of resistant strains of bacteria to all classes of antimicrobials limited their efficacy. The present study was aimed at evaluating the effect of combinations of antibiotics on multi-drug resistant Gram-negative (MDRGN) bacteria. A liquid micro-broth dilution method was used to evaluate the antibacterial activity of 10 different classes of antimicrobials on 20 bacterial strains belonging to six different species. The antimicrobials were associated with phenylalanine β-naphthylamide (PAβN), an efflux pump inhibitor, and with other antimicrobials at their sub-inhibitory concentrations. The effectiveness of each combination was monitored using the minimal inhibitory concentration (MIC) and the fractional inhibitory concentration (FIC). Most of the antimicrobials tested showed low antibacterial activity with a MIC value of 128 mg/L on a majority of the bacterial strains, justifying their multidrug-resistant (MDR) profile. Synergistic effects were mostly observed (FIC≤0.5) when ampicillin (AMP), cloxacillin (CLX), erythromycin (ERY), chloramphenicol (CHL), kanamycin (KAN) and streptomycin (STR) were combined with tetracycline (TET) at the sub-inhibitory concentration of MIC/5 or MIC/10. The results of the present work suggest that the association of several antimicrobials with TET could improve the fight against MDRGN bacterial species. Copyright © 2014 King Saud Bin Abdulaziz University for Health Sciences. Published by Elsevier Ltd. All rights reserved.

Antimicrobial potential of Dialium guineense (Wild.) stem bark on some clinical isolates in Nigeria

PubMed Central

Olajubu, FA; Akpan, I; Ojo, DA; Oluwalana, SA

2012-01-01

Context: The persistent increase in the number of antibiotic-resistant strains of microorganisms has led to the development of more potent but also more expensive antibiotics. In most developing countries of the world these antibiotics are not readily affordable, thus making compliance difficult. This calls for research into alternative sources of antimicrobials. Dialium guineense is a shrub of the family Leguminosae. Its stem bark is used for the treatment of cough, toothache, and bronchitis. Aims: Despite the acclaimed efficacy of D guineense, there is no scientific evidence in its support. This work was carried out to assess the antimicrobial activity of D guineense in vitro against some clinical isolates. Materials and Methods: D guineense stem bark was collected and 50 gm of air-dried and powdered stem bark of the plant was soaked for 72 hours in 1 l of each of the six solvents used in this study. Each mixture was refluxed, agitated at 200 rpm for 1 hour, filtered using Whatman No. 1 filter paper and, finally, freeze dried. The extracts were then tested for antimicrobial activity using the agar diffusion method. Results: The highest percentage yield of 23.2% was obtained with ethanol. Phytochemical screening showed that D guineense contains anthraquinone, alkaloids, flavonoids, tannins, and saponins. The antimicrobial activity of the extracts revealed a broad spectrum of activity, with Salmonella typhi and Staphylococcus aureusa showing the greatest zones of inhibition (18.0 mm). Only Candida albicans among the fungi tested was inhibited by the extract. The greatest zone of inhibition among the fractions was 16.0 mm. D guineense exhibited bactericidal activity at the 7th and 9th hours against Streptococcus pneumoniae and S. aureus 25923 while the 10th hour against S. typhi and C. albicans. The greatest activity was noted against S pneumoniae, where there was reduced viable cell count after 6 hours of exposure. Conclusion: Stem bark extract of D guineense (Wild.) has the potential to be developed into an antimicrobial agent PMID:23776811

Antimicrobial activity and properties of irreversible hydrocolloid impression materials incorporated with silver nanoparticles.

PubMed

Ginjupalli, Kishore; Alla, Rama Krishna; Tellapragada, Chaitanya; Gupta, Lokendra; Upadhya Perampalli, Nagaraja

2016-06-01

Conventional spray and the immersion disinfection of irreversible hydrocolloid impression materials may lead to dimensional changes. The purpose of this in vitro study was to investigate the antimicrobial activity and properties of irreversible hydrocolloid impression materials incorporated with silver nanoparticles. The antimicrobial activity and properties of 2 commercially available irreversible hydrocolloid impression materials were evaluated after incorporating varying concentrations of silver nanoparticles. Antimicrobial activity was determined using the disk diffusion method. The gel strength, permanent deformation, flow, and gelation time were measured according to American Dental Association specification #18. Analysis of variance was used to identify the significant differences within and across the groups (α=.05). Adding silver nanoparticles to irreversible hydrocolloid impression materials resulted in superior antimicrobial activity without adversely affecting their properties. Adding silver nanoparticles to Zelgan significantly increased the gel strength compared with the control group, except at 5 wt%. However, the gel strength of Tropicalgin was unaffected except at 5 wt%. An increase in the permanent deformation was found with the incorporation of silver nanoparticles in both Zelgan and Tropicalgin. The flow of Zelgan increased with the incorporation of silver nanoparticles, whereas a decrease in the flow of Tropicalgin was observed at 1 wt% and 2 wt%. An increase in the gelation time of both Zelgan and Tropicalgin was observed with the incorporation of silver nanoparticles. Based on this in vitro study, silver nanoparticles can be incorporated into irreversible hydrocolloid impression materials as antimicrobial agents without adversely affecting their properties. Copyright © 2016 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

Antimicrobial activity against oral pathogens and immunomodulatory effects and toxicity of geopropolis produced by the stingless bee Melipona fasciculata Smith

PubMed Central

2011-01-01

Background Native bees of the tribe Meliponini produce a distinct kind of propolis called geopropolis. Although many pharmacological activities of propolis have already been demonstrated, little is known about geopropolis, particularly regarding its antimicrobial activity against oral pathogens. The present study aimed at investigating the antimicrobial activity of M. fasciculata geopropolis against oral pathogens, its effects on S. mutans biofilms, and the chemical contents of the extracts. A gel prepared with a geopropolis extract was also analyzed for its activity on S. mutans and its immunotoxicological potential. Methods Antimicrobial activities of three hydroalcoholic extracts (HAEs) of geopropolis, and hexane and chloroform fractions of one extract, were evaluated using the agar diffusion method and the broth dilution technique. Ethanol (70%, v/v) and chlorhexidine (0.12%, w/w) were used as negative and positive controls, respectively. Total phenol and flavonoid concentrations were assayed by spectrophotometry. Immunotoxicity was evaluated in mice by topical application in the oral cavity followed by quantification of biochemical and immunological parameters, and macro-microscopic analysis of animal organs. Results Two extracts, HAE-2 and HAE-3, showed inhibition zones ranging from 9 to 13 mm in diameter for S. mutans and C. albicans, but presented no activity against L. acidophilus. The MBCs for HAE-2 and HAE-3 against S. mutans were 6.25 mg/mL and 12.5 mg/mL, respectively. HAE-2 was fractionated, and its chloroform fraction had an MBC of 14.57 mg/mL. HAE-2 also exhibited bactericidal effects on S. mutans biofilms after 3 h of treatment. Significant differences (p < 0.05) in total phenol and flavonoid concentrations were observed among the samples. Signs toxic effects were not observed after application of the geopropolis-based gel, but an increase in the production of IL-4 and IL-10, anti-inflammatory cytokines, was detected. Conclusions In summary, geopropolis produced by M. fasciculata can exert antimicrobial action against S. mutans and C. albicans, with significant inhibitory activity against S. mutans biofilms. The extract with the highest flavonoid concentration, HAE-2, presented the highest antimicrobial activity. In addition, a geopropolis-based gel is not toxic in an animal model and displays anti-inflammatory effect. PMID:22053900

Synthesis, X-ray diffraction method, spectroscopic characterization (FT-IR, 1H and 13C NMR), antimicrobial activity, Hirshfeld surface analysis and DFT computations of novel sulfonamide derivatives

NASA Astrophysics Data System (ADS)

Demircioğlu, Zeynep; Özdemir, Fethi Ahmet; Dayan, Osman; Şerbetçi, Zafer; Özdemir, Namık

2018-06-01

Synthesized compounds of N-(2-aminophenyl)benzenesulfonamide 1 and (Z)-N-(2-((2-nitrobenzylidene)amino)phenyl)benzenesulfonamide 2 were characterized by antimicrobial activity, FT-IR, 1H and 13C NMR. Two new Schiff base ligands containing aromatic sulfonamide fragment of (Z)-N-(2-((3-nitrobenzylidene)amino)phenyl)benzenesulfonamide 3 and (Z)-N-(2-((4-nitrobenzylidene)amino)phenyl)benzenesulfonamide 4 were synthesized and investigated by spectroscopic techniques including 1H and 13C NMR, FT-IR, single crystal X-ray diffraction, Hirshfeld surface, theoretical method analyses and by antimicrobial activity. The molecular geometry obtained from the X-ray structure determination was optimized Density Functional Theory (DFT/B3LYP) method with the 6-311++G(d,p) basis set in ground state. From the optimized geometry of the molecules of 3 and 4, the geometric parameters, vibrational wavenumbers and chemical shifts were computed. The optimized geometry results, which were well represented the X-ray data, were shown that the chosen of DFT/B3LYP 6-311G++(d,p) was a successful choice. After a successful optimization, frontier molecular orbitals, chemical activity, non-linear optical properties (NLO), molecular electrostatic mep (MEP), Mulliken population method, natural population analysis (NPA) and natural bond orbital analysis (NBO), which cannot be obtained experimentally, were calculated and investigated.

Antimicrobial activity of essential oil and aqueous and ethanol extracts of Teucrium polium L. subsp. gabesianum (L.H.) from Tunisia.

PubMed

Ben Othman, Mahmoud; Bel Hadj Salah-Fatnassi, Karima; Ncibi, Saida; Elaissi, Amer; Zourgui, Lazhar

2017-07-01

The antimicrobial effects of essential oil, ethanol and aqueous extracts of Teucrium polium L. were investigated against 13 microorganisms. Extracts and essential oil were obtained from maceration, decoction and hydrodistillation respectively. Samples were tested for their antimicrobial activity using the disk diffusion, the agar dilution and the agar incorporation method. Essential oil was analysed using GC/MS, results showed that β-pinene (35.97%) and α-pinene (13.32%) were the main components. Furthermore, essential oil exhibited the highest antimicrobial activity, it was most effective against Proteus mirabilis, Staphylococcus aureus and Citrobacter freundei where inhibition zone ranged between 15 and 25 mm, and with the microbial inhibitory concentration (MIC) values of 0.078-0.156 mg/ml. The oil and ethanol extract showed the best antifungal activity against Microsporum canis , Scopulariopsis brevicaulis , and Trichophyton rubrum with the inhibition percentage (I%) ranging from 18.94 to 100%. However, none of the samples exhibited antifungal activity against Aspergillus fumigatus . In this study, the obtained results showed significant effects of essential oils and ethanol extracts of T. polium which may used as a substitute to the synthetic drugs against certain microbial diseases.

[Diversity and antimicrobial activities of cultivable bacteria isolated from Jiaozhou Bay].

PubMed

Wang, Yiting; Zhang, Chuanbo; Qi, Lin; Jia, Xiaoqiang; Lu, Wenyu

2016-12-04

Marine microorganisms have a great potential in producing biologically active secondary metabolites. In order to study the diversity and antimicrobial activity, we explored 9 sediment samples in different observation sites of Jiaozhou bay. We used YPD and Z2216E culture medium to isolate bacteria from the sediments; 16S rRNA was sequenced for classification and identification of the isolates. Then, we used Oxford cup method to detect antimicrobial activities of the isolated bacteria against 7 test strains. Lastly, we selected 16 representatives to detect secondary-metabolite biosynthesis genes:PKSI, NRPS, CYP, PhzE, dTGD by PCR specific amplification. A total of 76 bacterial strains were isolated from Jiaozhou bay; according to the 16S rRNA gene sequence analysis. These strains could be sorted into 11 genera belonging to 8 different families:Aneurinibacillus, Brevibacillus, Microbacterium, Oceanisphae, Bacillus, Marinomonas, Staphylococcus, Kocuria, Arthrobacters, Micrococcus and Pseudoalteromonas. Of them 34 strains showed antimicrobial activity against at least one of the tested strains. All 16 strains had at least one function genes, 5 strains possessed more than three function genes. Jiaozhou bay area is rich in microbial resources with potential in providing useful secondary metabolites.

Antimicrobial activity of essential oils from Mediterranean aromatic plants against several foodborne and spoilage bacteria.

PubMed

Silva, Nuno; Alves, Sofia; Gonçalves, Alexandre; Amaral, Joana S; Poeta, Patrícia

2013-12-01

The antimicrobial activity of essential oils extracted from a variety of aromatic plants, often used in the Portuguese gastronomy was studied in vitro by the agar diffusion method. The essential oils of thyme, oregano, rosemary, verbena, basil, peppermint, pennyroyal and mint were tested against Gram-positive (Listeria monocytogenes, Clostridium perfringens, Bacillus cereus, Staphylococcus aureus, Enterococcus faecium, Enterococcus faecalis, and Staphylococcus epidermidis) and Gram-negative strains (Salmonella enterica, Escherichia coli, and Pseudomonas aeruginosa). For most essential oils examined, S. aureus, was the most susceptible bacteria, while P. aeruginosa showed, in general, least susceptibility. Among the eight essential oils evaluated, thyme, oregano and pennyroyal oils showed the greatest antimicrobial activity, followed by rosemary, peppermint and verbena, while basil and mint showed the weakest antimicrobial activity. Most of the essential oils considered in this study exhibited a significant inhibitory effect. Thyme oil showed a promising inhibitory activity even at low concentration, thus revealing its potential as a natural preservative in food products against several causal agents of foodborne diseases and food spoilage. In general, the results demonstrate that, besides flavoring the food, the use of aromatic herbs in gastronomy can also contribute to a bacteriostatic effect against pathogens.

[Screening of antifungi endophytic actinomyces strains from salvia przewalskii in Tibean Plateau].

PubMed

Liu, Song-Qing; Jiang, Hua-Ming; Guan, Tong-Wei; Qi, Shan-Shan; Gu, Yun-Fu; Zhao, Ke; Wang, Xu; Zhang, Xiao-Ping

2013-10-01

Twenty-four endophytic actinomycetes strains were isolated from the Salvia przewalskii in Tibetan Plateau of China by tablet coating method. Fusarium moniliforme, Helminthosporium turcicum and Bipolaris maydis were selected as indicator fungi to test the antimicrobial activities of these endophytic actinomycetes by tablet confrontation method. The results showed that 21 strains can produce antimicrobial substances which accounts for 85.7% of the total separates number. Four strains of endogenous actinomyces have more obvious antifungi activity. According to results of morphology and culture properties and 16S rDNA sequences of endophytic actinomyces, it is concluded that all of the isolates were streptomycetes trains.

Antimicrobial Activities of Silver Nanoparticles Synthesized by Using Water Extract of Arnicae anthodium.

PubMed

Dobrucka, Renata; Długaszewska, Jolanta

2015-06-01

Green synthesis of nanoparticles has gained significant importance in recent years and has become the one of the most preferred methods. Also, green synthesis of nanoparticles is valuable branch of nanotechnology. Plant extracts are eco-friendly and can be an economic option for synthesis of nanoparticles. This study presents method the synthesis of silver nanoparticles using water extract of Arnicae anthodium. Formation of silver nanoparticles was confirmed by UV-visble spectroscopy, Fourier transform infrared spectroscopy and total reflection X-ray fluorescence analysis. The morphology of the synthesized silver nanoparticles was verified by SEM-EDS. The obtained silver nanoparticles were used to study their antimicrobial activity.

In-vitro bio-fabrication of silver nanoparticle using Adhathoda vasica leaf extract and its anti-microbial activity

NASA Astrophysics Data System (ADS)

Nazeruddin, G. M.; Prasad, N. R.; Prasad, S. R.; Garadkar, K. M.; Nayak, Arpan Kumar

2014-07-01

It is well known that on treating the metallic salt solution with some plant extracts, a rapid reduction occurs leading to the formation of highly stable metal nanoparticles. Extracellular synthesis of metal nanoparticles using extracts of plants like Azadirachta indica (Neem), and Zingiber officinale (Ginger) has been reported to be successfully carried out. In this study we have developed a novel method to synthesize silver nanoparticles by mixing silver salt solution with leaf extract of Adhathoda vasica (Adulsa) without using any surfactant or external energy. By this method physiologically stable, bio-compatible Ag nanoparticles were formed which could be used for a variety of applications such as targeted drug delivery which ensures enhanced therapeutic efficacy and minimal side effects. With this method rapid synthesis of nanoparticles was observed to occur; i.e. reaction time was 1-2 h as compared to 2-4 days required by microorganisms. These nanoparticles were analyzed by various characterization techniques to reveal their morphology, chemical composition, and antimicrobial activity. TEM image of these NPs indicated the formation of spherical, non-uniform, poly-dispersed nanoparticles. A detailed study of anti-microbial activity of nanoparticles was carried out.

Antimicrobial and antifungal activities of the extracts and essential oils of Bidens tripartita.

PubMed

Tomczykowa, Monika; Tomczyk, Michał; Jakoniuk, Piotr; Tryniszewska, Elzbieta

2008-01-01

The aim of this study was to determine the antibacterial and antifungal properties of the extracts, subextracts and essential oils of Bidens tripartita flowers and herbs. In the study, twelve extracts and two essential oils were investigated for activity against different Gram-positive Bacillus subtilis, Micrococcus luteus, Staphylococcus aureus, Gram-negative bacteria Escherichia coli, E. coli (beta-laktamase+), Klebsiella pneumoniae (ESBL+), Pseudomonas aeruginosa and some fungal organisms Candida albicans, C. parapsilosis, Aspergillus fumigatus, A. terreus using a broth microdilution and disc diffusion methods. The results obtained indicate antimicrobial activity of the tested extracts (except butanolic extracts), which however did not inhibit the growth of fungi used in this study. Bacteriostatic effect of both essential oils is insignificant, but they have strong antifungal activity. These results support the use of B. tripartita to treat a microbial infections and it is indicated as an antimicrobial and antifungal agent, which may act as pharmaceuticals and preservatives.

Influence of baking enzymes on antimicrobial activity of five bacteriocin-like inhibitory substances produced by lactic acid bacteria isolated from Lithuanian sourdoughs.

PubMed

Narbutaite, V; Fernandez, A; Horn, N; Juodeikiene, G; Narbad, A

2008-12-01

To evaluate the effect of four different baking enzymes on the inhibitory activity of five bacteriocin-like inhibitory substances (BLIS) produced by lactic acid bacteria (LAB) isolated from Lithuanian sourdoughs. The overlay assay and the Bioscreen methods revealed that the five BLIS exhibited an inhibitory effect against spore germination and vegetative outgrowth of Bacillus subtilis, the predominant species causing ropiness in bread. The possibility that the observed antibacterial activity of BLIS might be lost after treatment with enzymes used for baking purposes was also examined. The enzymes tested; hemicellulase, lipase, amyloglucosidase and amylase had little or no effect on the majority of the antimicrobial activities associated with the five BLIS studied. This study suggests a potential application in the sourdough baking industry for these antimicrobial producing LAB strains in the control of B. subtilis spore germination and vegetative outgrowth.

Evaluation of antimicrobial activity of extracts of Tibouchina candolleana (melastomataceae), isolated compounds and semi-synthetic derivatives against endodontic bacteria.

PubMed

Dos Santos, Fernanda M; de Souza, Maria Gorete; Crotti, Antônio E Miller; Martins, Carlos H G; Ambrósio, Sérgio R; Veneziani, Rodrigo C S; E Silva, Márcio L Andrade; Cunha, Wilson R

2012-04-01

This work describes the phytochemical study of the extracts from aerial parts of Tibouchina candolleana as well as the evaluation of the antimicrobial activity of extracts, isolated compounds, and semi-synthetic derivatives of ursolic acid against endodontic bacteria. HRGC analysis of the n-hexane extract of T. candolleana allowed identification of β-amyrin, α-amyrin, and β-sitosterol as major constituents. The triterpenes ursolic acid and oleanolic acid were isolated from the methylene chloride extract and identified. In addition, the flavonoids luteolin and genistein were isolated from the ethanol extract and identified. The antimicrobial activity was investigated via determination of the minimum inhibitory concentration (MIC) using the broth microdilution method. Amongst the isolated compounds, ursolic acid was the most effective against the selected endodontic bacteria. As for the semi-synthetic ursolic acid derivatives, only the methyl ester derivative potentiated the activity against Bacteroides fragilis.

Evaluation of antimicrobial activity of extracts of Tibouchina candolleana (melastomataceae), isolated compounds and semi-synthetic derivatives against endodontic bacteria

PubMed Central

dos Santos, Fernanda M.; de Souza, Maria Gorete; Crotti, Antônio E. Miller; Martins, Carlos H. G.; Ambrósio, Sérgio R.; Veneziani, Rodrigo C. S.; e Silva, Márcio L. Andrade; Cunha, Wilson R.

2012-01-01

This work describes the phytochemical study of the extracts from aerial parts of Tibouchina candolleana as well as the evaluation of the antimicrobial activity of extracts, isolated compounds, and semi-synthetic derivatives of ursolic acid against endodontic bacteria. HRGC analysis of the n-hexane extract of T. candolleana allowed identification of β-amyrin, α-amyrin, and β-sitosterol as major constituents. The triterpenes ursolic acid and oleanolic acid were isolated from the methylene chloride extract and identified. In addition, the flavonoids luteolin and genistein were isolated from the ethanol extract and identified. The antimicrobial activity was investigated via determination of the minimum inhibitory concentration (MIC) using the broth microdilution method. Amongst the isolated compounds, ursolic acid was the most effective against the selected endodontic bacteria. As for the semi-synthetic ursolic acid derivatives, only the methyl ester derivative potentiated the activity against Bacteroides fragilis. PMID:24031892

Antimicrobial and antioxidant activity of the essential oil from the Carpathian Thymus alternans Klokov.

PubMed

Vitali, Luca A; Dall'Acqua, Stefano; Maggi, Filippo; Martonfi, Pavol; Papa, Fabrizio; Petrelli, Dezemona; Sut, Stefania; Lupidi, Giulio

2017-05-01

The genus Thymus includes several species that are used as flavouring, food preservative as well as in cosmetics. Their secondary metabolites have been extensively studied for pharmacological effects. Nonetheless, some species are neglected and deserve to be explored for chemical composition and biological activities. This is the case with Thymus alternans, a Carpathian bush used as a food additive and for the preparation of a traditional herbal medicine. In this work, we have analysed the chemical composition of T. alternans essential oil by GC and GC-MS and evaluated its antimicrobial and antioxidant activity by disc diffusion, DPPH, ABTS and FRAP methods, respectively. Results showed that T. alternans belongs to the nerolidol chemotype, being rich of this sesquiterpene alcohol (15.8%) which might contribute to the antimicrobial (particularly effective on C. albicans growth) and antioxidant (weak inhibition on ABTS radical and reducing power) activities observed.

Antimicrobial activity of suspensions and nanoemulsions of citral in combination with heat or pulsed electric fields.

PubMed

Pagán, E; Berdejo, D; Espina, L; García-Gonzalo, D; Pagán, R

2018-01-01

The application of essential oils in form of nanoemulsions has been proposed as a method to improve their solubility in aqueous solutions, and hence their antimicrobial activity. The objective of this study was to evaluate the antimicrobial activity of citral, applied directly or in combined treatments with heat or pulsed electric fields (PEF), as a function of the inoculation procedure assayed: (i) a simple, vigorous shaking method by vortex agitation (suspension of citral; s-citral) or (ii) the previous preparation of nanoemulsions by the emulsion phase inversion (EPI) method (nanoemulsion of citral; n-citral). n-Citral was more effective in either inhibiting or inactivating Escherichia coli O157:H7 Sakai than s-citral. However, when combined with heat, a greater synergistic effect was observed with s-citral rather than with n-citral, either in lab media (pH 7·0 and 4·0) or apple juice. For instance, while almost 5 log 10 cell cycles were inactivated in apple juice after 15 min at 53°C in the presence of 0·1 μl ml -1 of s-citral, the use of n-citral required 30 min. The use of nanoemulsions did not modify the slight synergism observed when citral and mild PEF were combined (150 μs, 30 kV cm -1 ). The exploration of different delivery systems of antimicrobial compounds such as citral in aqueous food products aids in the establishment of successful combined treatments for food preservation. While at room temperature, citral in form of a nanoemulsion shows a higher antimicrobial activity; its combination with heat would imply a partial loss of the outstanding synergistic lethal effect achieved when added in suspension form. Therefore, the most suitable procedure to magnify the synergism between heat and citral when processing juices would merely require an intense homogenization step prior to the combined treatment. © 2017 The Society for Applied Microbiology.

In vitro evaluation of cytotoxic, anti-proliferative, anti-oxidant, apoptotic, and anti-microbial activities of Cladonia pocillum.

PubMed

Ersoz, M; Coskun, Z M; Acikgoz, B; Karalti, I; Cobanoglu, G; Cesal, C

2017-08-15

The aim of this study was to investigate the anti-proliferative, apoptotic, cytotoxic, and anti-oxidant effects of extracts from the lichen Cladonia pocillumon human breast cancer cells (MCF-7), and to characterize the anti-microbial features.  MCF-7 cells were treated with methanolic C. pocillum extract for 24h. The cytotoxicity of the extract was tested with MTT. Moreover, its anti-proliferative effects were examined with immunocytochemical method. Apoptosis and biochemical parameters were detected in MCF-7. The methanol and chloroform extracts of the lichen were tested for anti-microbial activity against Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, Pseudomonas aeruginosa, and Candida albicans using the disc diffusion method and calculation of minimal inhibitory concentrations. Although BrdU incorporation was not observed in MCF-7 cells treated with methanol extract at a concentration above 0.2 mg/mL, a significant decrease was observed int he percentage of PCNA immunoreactive cells in groups treated with 0.2, 0.4, 06, and 0.8 mg/mL methanol extracts of C.pocillum (49±6.3, 44±5.2, 23±2.5, 0, respectively) compared to that of control (85±4.5). The percentage of apoptotic cells significantly increased in groups treated with 0.2, 0.4, 0.6, and 0.8 mg/mL extracts of the C.pocillum (54±3.5, 76±2.6, 77±1.8, 82±4.2, respectively) compared with that of control group (3.9±1.5).The half-maximal inhibitory concentration of the methanol extract against MCF-7 cells was 0.802 mg/mL .Although the chloroform extract showed more effective anti-microbial activity overall, the methanol extract showed higher anti-fungal activity. Collectively, the results of our study indicate that C.pocillum extracts have strong anti-microbial and apoptotic effects. This lichen therefore shows potential for development as a natural anti-microbial, anti-oxidant, and apoptotic agent.

In Vitro Antimicrobial and Antiproliferative Activity of Amphipterygium adstringens

PubMed Central

Rodriguez-Garcia, A.; Peixoto, I. T. A.; Verde-Star, M. J.; De la Torre-Zavala, S.; Aviles-Arnaut, H.; Ruiz, A. L. T. G.

2015-01-01

Amphipterygium adstringens is a plant widely used in Mexican traditional medicine for its known anti-inflammatory and antiulcer properties. In this work, we evaluated the in vitro antimicrobial and antiproliferative activities of the methanolic extract of A. adstringens against oral pathogens such as Streptococcus mutans, Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans, Candida albicans, and Candida dubliniensis, using microdilution (MIC) and agar diffusion methods (MBC), and the antiproliferative activity evaluating total growth inhibition (TGI) by staining the protein content with sulforhodamine B (SRB), using nine human cancer cell lines. Crude extract (CE) of A. adstringens showed some degree of activity against one or more of the strains with a MIC from 0.125 mg/mL to 63 mg/mL and MBC from 1.6 to 6.3 mg/mL and cytotoxic activity, particularly against NCI-ADR/RES, an ovarian cell line expressing multiple resistance drugs phenotype. The CE is a complex mixture of possible multitarget metabolites that could be responsible for both antimicrobial and antiproliferative activities, and further investigation is required to elucidate the identity of active compounds. Nevertheless the CE itself is useful in the development of new antimicrobial treatment based on natural products to prevent oral diseases and as alternative natural source for cancer treatment and prevention. PMID:26451151

Use of rosemary, oregano, and a commercial blend of essential oils in broiler chickens: in vitro antimicrobial activities and effects on growth performance.

PubMed

Mathlouthi, N; Bouzaienne, T; Oueslati, I; Recoquillay, F; Hamdi, M; Urdaci, M; Bergaoui, R

2012-03-01

The present study was conducted to characterize the in vitro antimicrobial activities of 3 essential oils [oregano, rosemary, and a commercial blend of essential oils (BEO)] against pathogenic and nonpathogenic bacteria and to evaluate their effects on broiler chicken performances. The chemical composition of the essential oils was determined using the gas chromatography interfaced with a mass spectroscopy. The disc diffusion method, the minimum inhibitory concentration (MIC), and the minimum bactericidal concentration (MBC) were applied for the determination of antimicrobial activities of essential oils. In vivo study, a total of seven hundred fifty 1-d-old male broiler chickens were assigned to 6 dietary treatment groups: basal diet (control; CON), CON + 44 mg of avilamycin/kg (A), CON + 100 mg of rosemary essential oil/kg (ROS), CON + 100 mg of oregano essential oil/kg (OR), CON + 50 mg of rosemary and 50 mg of oregano essential oils/kg (RO), and CON + 1,000 mg of BEO/kg (essential oil mixture, EOM). The essential oils isolated from rosemary and oregano were characterized by their greater content of 1,8-cineole (49.99%) and carvacrol (69.55%), respectively. The BEO was mainly represented by the aldehyde (cinnamaldehyde) and the monoterpene (1,8-cineole) chemical groups. The results of the disc diffusion method indicated that the rosemary essential oil had antibacterial activity (P ≤ 0.05) against only 3 pathogenic bacteria, Escherichia coli (8 mm), Salmonella indiana (11 mm), and Listeria innocua (9 mm). The essential oil of oregano had antimicrobial activities (P ≤ 0.05) on the same bacteria as rosemary but also on Staphylococcus aureus (22 mm) and Bacillus subtilis (12 mm). Oregano essential oil had greater (P ≤ 0.05) antimicrobial activities against pathogenic bacteria than rosemary essential oil but they had no synergism between them. The BEO showed an increased antimicrobial activity (P ≤ 0.05) against all studied bacteria (pathogenic and nonpathogenic bacteria) except for Lactobacillus rhamnosus. The supplementation of the basal diet with avilamycin or essential oils improved (P ≤ 0.05) broiler chicken BW, BW gain, and G:F compared with the CON diet. There were no differences in growth performances among birds fed A, ROS, OR, RO, or EOM diets. In general, essential oils contained in rosemary, oregano, and BEO can substitute for growth promoter antibiotics. Although the 3 essential oils had different antimicrobial activities, they exhibited the same efficiency in broiler chickens.

A Review of Antimicrobial Peptides and Their Therapeutic Potential as Anti-Infective Drugs

PubMed Central

Gordon, Y. Jerold; Romanowski, Eric G.; McDermott, Alison M.

2006-01-01

Purpose. Antimicrobial peptides (AMPs) are an essential part of innate immunity that evolved in most living organisms over 2.6 billion years to combat microbial challenge. These small cationic peptides are multifunctional as effectors of innate immunity on skin and mucosal surfaces and have demonstrated direct antimicrobial activity against various bacteria, viruses, fungi, and parasites. This review summarizes their progress to date as commercial antimicrobial drugs for topical and systemic indications. Methods. Literature review. Results. Despite numerous clinical trials, no modified AMP has obtained Food & Drug Administration approval yet for any topical or systemic medical indications. Conclusions. While AMPs are recognized as essential components of natural host innate immunity against microbial challenge, their usefulness as a new class of antimicrobial drugs still remains to be proven. PMID:16020284

The addition of nanochitosan suspension as filler in carrageenan-tapioca biocomposite film

NASA Astrophysics Data System (ADS)

Rochima, Emma; Fiyanih, Elisah; Afrianto, Eddy; Subhan, Ujang; Praseptiangga, Danar; Panatarani, Camellia; Joni, I. Made

2018-02-01

This research aimed to investigate the effect of nanochitosan (CSNPs) suspension by beads milling method as filler in carrageenan-tapioca biocomposite film. In addition, the antibacterial activity of CSNPs as filler with two food pathogenic bacteria, Staphylococcus aureus and Escherichia coli and then influence of nano fillers for appearance of films were observed. The incorporation of CSNPs suspension with 0.5, 1, 1.5 and 2 (%v/v) in carrageenan-tapioca film exhibited antibacterial activity againts both bacteria. CSNPs had slightly higher antimicrobial activity against E. coli aureus compared to S. aureus at all concentrations due to different mechanisms. Therefore, the best antimicrobial activity was obtained from 1 wt%. Furthermore the best antimicrobial activity was characterized by means of the thickness and transparency. The result showed that the thickness of film was 0.059 mm and the transparency was 87.88. It was concluded that the incorporation of CSNPs suspension 1 wt% in carrageenan-tapioca composite film is suitable for developing active packaging.

Synthesis, characterisaion and antimicrobial activity of polypropylenamine metallodendrimers modified with 1,8-naphthalimides

NASA Astrophysics Data System (ADS)

Staneva, Desislava; Grabchev, Ivo; Bosch, Paula; Vasileva-Tonkova, Evgenia; Kukeva, Rositsa; Stoyanova, Radostina

2018-07-01

Two novel metal complexes of modified with 1,8-naphthalimide poly(propylenamine) dendrimer of first generation have been synthesized and characterized. By different analytical methods it was shown that the complex composition includes one ligand and one metal ion. The antimicrobial activity of the dendrimer and metallodendrimers was investigated in vitro against different Gram-positive and Gram-negative bacteria and yeasts. The antibacterial effect of thin polylactide film impregnated with the new compounds was also evaluated.

High prevalence of multidrug-resistant Escherichia coli isolates from children with and without diarrhoea and their susceptibility to the antibacterial activity of extracts/fractions of fruits native to Mexico.

PubMed

Uribe-Beltrán, Magdalena de Jesús; Ahumada-Santos, Yesmi Patricia; Díaz-Camacho, Sylvia Páz; Eslava-Campos, Carlos Alberto; Reyes-Valenzuela, Jesús Ernesto; Báez-Flores, María Elena; Osuna-Ramírez, Ignacio; Delgado-Vargas, Francisco

2017-07-01

This paper aims to evaluate the antimicrobial resistance of Esherichia coli isolates from children under 5 years old, with and without diarrhoea, who were hospital outpatients in Culiacan, Sinaloa, Mexico. It also looks at the antimicrobial activity of fruit extracts against selected multidrug-resistant (MDR) E. coli strains. A total of 205 E. coli isolates from stool samples were collected from 94 children under 5 years old who were outpatients from two hospitals in the city of Culiacan, Sinaloa, Mexico, during the autumn/winter of 2003/04; their resistance profiles to 19 commercial antimicrobials were investigated using the Kirby-Bauer method. The antibacterial activities of extracts/fractions of fruits (i.e. uvalama, Vitex mollis; ayale, Crescentia alata; and arrayan, Psidium sartorianum) were evaluated using the broth microdilution method. All E. coli isolates were susceptible to amikacin, nitrofurantoin and meropenem, and approximately 96 % were resistant to at least one antimicrobial, especially carbenicillin (93.2 %), cefuroxime sodium (53.7 %), ampicillin (40 %) and trimethoprim/sulfamethoxazole (35.1 %). Likewise, the frequency of MDR strains (44.9 %) was high, and no significant association with diarrhoea symptoms was found. Remarkably, all fruit extracts/fractions showed antibacterial activity against some, but not all, MDR isolates. The lowest minimal inhibitory concentration values were for the hexane fraction of arrayan (0.25 mg ml-1). A high number of antimicrobial-resistant E. coli (especially to β-lactams and sulfonamides) and MDR isolates were detected in children under 5 years old, irrespective of diarrhoea symptoms; this is novel information for Culiacan, Sinaloa, Mexico. Moreover, our results showed that the studied fruit extracts/fractions are potential alternative or complementary treatments for MDR E. coli strains.

The antimicrobial activity of probiotic bacteria Escherichia coli isolated from different natural sources against hemorrhagic E. coli O157:H7.

PubMed

Karimi, Sahar; Azizi, Fatemeh; Nayeb-Aghaee, Mohammad; Mahmoodnia, Leila

2018-03-01

Diarrheal diseases have been seen in all geographical areas throughout the world. Therefore, considering treatment, could be deemed a necessary action. The aim of this study was to determine the antimicrobial effect of probiotic bacterial strains isolated from different natural sources against 2 pathotypes of pathogenic E. coli. This cross-sectional study of Martyr Chamran University of Ahvaz was carried out from December 2013 to July 2014. A total of 13 probiotic colonies isolated from 20 samples of traditional dairy products including (yogurt, cheese, milk) and 20 samples of vegetables including carrots and cabbages (red and white) of which 5 isolates were selected to evaluate the antimicrobial effect against 2 Escherichia coli pathotypes, randomly. Antimicrobial effect was evaluated using two methods: disk diffusion and well diffusion tests and measuring growth inhibition zones of probiotics against 2 pathotypes of pathogenic E. coli. Obtained results showed growth inhibition effects of all 5 probiotic strains against Escherichia coli pathotypes in both used methods. All selected strains showed considerable antimicrobial effect on Escherichia coli O157:H7 strain, but had no inhibitory effect against Enterohemorrhagic Escherichia coli. This study demonstrated considerable antimicrobial effect against E. coli O157:H7 strain. Due to this, characteristic and similar antimicrobial effects of probiotics bacteria, increasing use of the probiotics as a natural and modern method for prevention of different diseases is recommended.

Mushrooms as Possible Antioxidant and Antimicrobial Agents

PubMed Central

Kosanić, Marijana; Ranković, Branislav; Dašić, Marko

2012-01-01

The aim of the study is to examine in-vitro antioxidant and antimicrobial activity of the acetonic and methanolic extracts of the mushrooms Boletus aestivalis, Boletus edulis and Leccinum carpini. Antioxidant activity was evaluated by using free radical scavenging activity and reducing power. In addition, total content of phenol and flavonoid in extracts were determined as pyrocatechol equivalent, and as rutin equivalent, respectively. As a result of the study acetonic extracts from Boletus edulis was more powerful antioxidant activity with IC50 value of 4.72 μg/mL which was similar or greater than the standard antioxidants, ascorbic acid (IC50 = 4.22 μg/mL), BHA (IC50 = 6.42 μg/mL) and α-tocopherol (IC50 = 62.43 μg/mL). Moreover, the tested extracts had effective reducing power. A significant relationship between total phenolic and flavonoid contents and their antioxidative activities was significantly observed. The antimicrobial activity of each extract was estimated by determination of the minimum inhibitory concentration by using microdilution plate method against five species of bacteria and five species of fungi. Generally, the tested mushroom extracts had relatively strong antimicrobial activity against the tested microorganisms. The minimum inhibitory concentration for both extracts related to the tested bacteria and fungi were 1.25 - 10 mg/ mL. The present study shows that tested mushroom species demonstrated a strong antioxidant and antimicrobial activity. It suggests that mushroom may be used as good sources of natural antioxidants and for pharmaceutical purposes in treating of various deseases. PMID:24250542

An immunological method for quantifying antibacterial activity in Salmo salar (Linnaeus, 1758) skin mucus.

PubMed

Narvaez, Edgar; Berendsen, Jorge; Guzmán, Fanny; Gallardo, José A; Mercado, Luis

2010-01-01

Antimicrobial peptides (AMPs) are a pivotal component of innate immunity in lower vertebrates. The aim of this study was to develop an immunological method for quantifying AMPs in Salmo salar skin mucus. A known antimicrobial peptide derived from histone H1 previously purified and described from S. salar skin mucus (SAMP H1) was chemically synthesized and used to obtain antibodies for the quantification of the molecule via ELISA. Using skin mucus samples, a correlation of bacterial growth inhibition versus SAMP H1 concentration (ELISA) was established. The results provide the first evidence for quantifying the presence of active AMPs in the skin mucus of S. salar through the use of an immunological method. Copyright 2009 Elsevier Ltd. All rights reserved.

Purification and characterization of two new cell-bound bioactive compounds produced by wild Lactococcus lactis strain.

PubMed

Saraiva, Margarete Alice Fontes; Brede, Dag Anders; Nes, Ingolf Figved; Baracat-Pereira, Maria Cristina; de Queiroz, Marisa Vieira; de Moraes, Célia Alencar

2017-07-03

Novel compounds and innovative methods are required considering that antibiotic resistance has reached a crisis point. In the study, two cell-bound antimicrobial compounds produced by Lactococcus lactis ID1.5 were isolated and partially characterized. Following purification by cationic exchange and a solid-phase C18 column, antimicrobial activity was recovered after three runs of RPC using 60% (v/v) and 100% (v/v) of 2-propanol for elution, suggesting that more than one antimicrobial compound were produced by L. lactis ID1.5, which were in this study called compounds AI and AII. The mass spectrum of AI and AII showed major intensity ions at m/z 1070.05 and 955.9 Da, respectively. The compound AI showed a spectrum of antimicrobial activity mainly against L. lactis species, while the organisms most sensitive to compound AII were Bacillus subtilis, Listeria innocua, Streptococcus pneumoniae and Pseudomonas aeruginosa. The antimicrobial activity of both compounds was suppressed by treatment with Tween 80. Nevertheless, both compounds showed high stability to heat and proteases treatments. The isolated compounds, AI and AII, showed distinct properties from other antimicrobial substances already reported as produced by L. lactis, and have a significant inhibitory effect against two clinically important respiratory pathogens. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Susceptibility of Escherichia coli isolated from uteri of postpartum dairy cows to antibiotic and environmental bacteriophages. Part II: In vitro antimicrobial activity evaluation of a bacteriophage cocktail and several antibiotics.

PubMed

Santos, T M A; Gilbert, R O; Caixeta, L S; Machado, V S; Teixeira, L M; Bicalho, R C

2010-01-01

The use of pathogenic-specific antimicrobials, as proposed by bacteriophage therapy, is expected to reduce the incidence of resistance development. Eighty Escherichia coli isolated from uteri of Holstein dairy cows were phenotypically characterized for antimicrobial resistance to ampicillin, ceftiofur, chloramphenicol, florfenicol, spectinomycin, streptomycin, and tetracycline by broth microdilution method. The lytic activity of a bacteriophage cocktail against all isolates was performed by a similar method. Additionally, the effect of different concentrations of antimicrobials and multiplicities of infections (MOI) of the bacteriophage cocktail on E. coli growth curve was measured. Isolates exhibited resistance to ampicillin (33.7%), ceftiofur (1.2%), chloramphenicol (100%), and florfenicol (100%). All strains were resistant to at least 2 of the antimicrobial agents tested; multidrug resistance (>or=3 of 7 antimicrobials tested) was observed in 35% of E. coli isolates. The major multidrug resistance profile was found for ampicillin-chloramphenicol-florfenicol, which was observed in more than 96.4% of the multidrug-resistant isolates. The bacteriophage cocktail preparation showed strong antimicrobial activity against multidrug-resistant E. coli. Multiplicity of infection as low as 10(-4) affected the growth of the E. coli isolates. The ratio of 10 bacteriophage particles per bacterial cell (MOI=10(1)) was efficient in inhibiting at least 50% of all isolates. Higher MOI should be tested in future in vitro studies to establish ratios that completely inhibit bacterial growth during longer periods. All isolates resistant to florfenicol were resistant to chloramphenicol and, because florfenicol was recently introduced into veterinary clinics, this finding suggests that the selection pressure of chloramphenicol, as well as other antimicrobials, may still play a relevant role in the emergence and dissemination of florfenicol resistance in E. coli. The bacteriophage cocktail had a notable capacity to inhibit the in vitro growth of E. coli isolates, and it may be an attractive alternative to conventional treatment of metritis by reducing E. coli in uteri of postpartum dairy cows. Copyright 2010 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Evaluation of the cytotoxic effect and antibacterial, antifungal, and antiviral activities of Hypericum triquetrifolium Turra essential oils from Tunisia

PubMed Central

2013-01-01

Background A number of bio-active secondary metabolites have been identified and reported for several Hypericum species. Many studies have reported the potential use of the plant extracts against several pathogens. However, Hypericum triquetrifolium is one of the least studied species for its antimicrobial activity. The aim of the present study was to evaluate the cytotoxic effect of the essential oils of Hypericum triquetrifolium as well as their antimicrobial potential against coxsakievirus B3 and a range of bacterial and fungal strains. Methods The essential oils of Hypericum triquetrifolium harvested from five different Tunisian localities (Fondouk DJedid, Bou Arada, Bahra, Fernana and Dhrea Ben Jouder) were evaluated for their antimicrobial activities by micro-broth dilution methods against bacterial and fungal strains. In addition, the cytotoxic effect and the antiviral activity of these oils were carried out using Vero cell lines and coxsakievirus B3. Results The results showed a good antibacterial activities against a wide range of bacterial strains, MIC values ranging between 0.39-12.50 mg/ml and MBC values between 1.56-25.0 mg/ml. In addition, the essential oils showed promising antifungal activity with MIC values ranging between 0.39 μg/mL and 12.50 μg/mL; MFC values ranged between 3.12 μg/mL and 25.00 μg/mL; a significant anticandidal activity was noted (MIC values comprised between 0.39 μg/mL and 12.50 μg/mL). Although their low cytotoxic effect (CC50 ranged between 0.58 mg/mL and 12.00 mg/mL), the essential oils did not show antiviral activity against coxsakievirus B3. Conclusion The essential oils obtained from Hypericum triquetrifolium can be used as antimicrobial agents and could be safe at non cytotoxic doses. As shown for the tested essential oils, comparative analysis need to be undertaken to better characterize also the antimicrobial activities of Hypericum triquetrifolium extracts with different solvents as well as their purified fractions and their pure secondary metabolites. PMID:23360506

Antioxidant and antimicrobial activities of bitter and sweet apricot (Prunus armeniaca L.) kernels.

PubMed

Yiğit, D; Yiğit, N; Mavi, A

2009-04-01

The present study describes the in vitro antimicrobial and antioxidant activity of methanol and water extracts of sweet and bitter apricot (Prunus armeniaca L.) kernels. The antioxidant properties of apricot kernels were evaluated by determining radical scavenging power, lipid peroxidation inhibition activity and total phenol content measured with a DPPH test, the thiocyanate method and the Folin method, respectively. In contrast to extracts of the bitter kernels, both the water and methanol extracts of sweet kernels have antioxidant potential. The highest percent inhibition of lipid peroxidation (69%) and total phenolic content (7.9 +/- 0.2 microg/mL) were detected in the methanol extract of sweet kernels (Hasanbey) and in the water extract of the same cultivar, respectively. The antimicrobial activities of the above extracts were also tested against human pathogenic microorganisms using a disc-diffusion method, and the minimal inhibitory concentration (MIC) values of each active extract were determined. The most effective antibacterial activity was observed in the methanol and water extracts of bitter kernels and in the methanol extract of sweet kernels against the Gram-positive bacteria Staphylococcus aureus. Additionally, the methanol extracts of the bitter kernels were very potent against the Gram-negative bacteria Escherichia coli (0.312 mg/mL MIC value). Significant anti-candida activity was also observed with the methanol extract of bitter apricot kernels against Candida albicans, consisting of a 14 mm in diameter of inhibition zone and a 0.625 mg/mL MIC value.

Antimicrobial Activity of Chitosan Film Forming Solution Enriched with Essential Oils; an in Vitro Assay

PubMed Central

Raphaël, Kana Jean; Meimandipour, Amir

2017-01-01

Background: The resistance of the bacteria and fungi to the innumerous antimicrobial agents is a major challenge in the treatment of the infections demands to the necessity for searching and finding new sources of substances with antimicrobial properties. The incorporation of the essential oils (EOs) in chitosan film forming solution may enhance antimicrobial properties. However, its use as the feeding additive in the poultry nutrition needs to clarify the product’s activity against both pathogen and the useful microbes in the gastrointestinal tract. Objectives: In the present study, we carried out an in vitro investigation and evaluated the antimicrobial activity of chitosan film forming solution incorporated with essential oils (CFs+EOs) against microbial strains including Staphylococcus aureus, Escherichia coli, Enterococcus faecium, Lactobacillus rahmnosus, Aspergillus niger and Alternaria alternate. Material and Methods: In three replicates, the minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) of different treatments including: 1- essential oils (EOs), 2- chitosan film solution (CFs), and 3-chitosan film solution enriched with EOs (CFs+EOs) were determined against above mentioned microbes. Results: The results indicated that the chitosan solution enriched with essential oils (CFs+EOs) is capable of inhibiting the bacterial and fungal growth even at the lowest concentrations. The MIC and MBC for all the antimicrobial agents against Escherichia coli and Staphylococcus aureus were very low compared to the concentrations needed to inhibit the growth of useful bacteria, Lactobacillus rahmnosu and Enterococcus faecium. The antifungal activity of chitosan was enhanced as the concentration of EOs increased in the film solution. Conclusion: Chitosan-EOs complexes are the promising candidate for novel contact antimicrobial agents that can be used in animal feeds. PMID:29845058

Antimicrobial Activity of Chitosan Film Forming Solution Enriched with Essential Oils; an in Vitro Assay.

PubMed

Raphaël, Kana Jean; Meimandipour, Amir

2017-01-01

Background: The resistance of the bacteria and fungi to the innumerous antimicrobial agents is a major challenge in the treatment of the infections demands to the necessity for searching and finding new sources of substances with antimicrobial properties. The incorporation of the essential oils (EOs) in chitosan film forming solution may enhance antimicrobial properties. However, its use as the feeding additive in the poultry nutrition needs to clarify the product's activity against both pathogen and the useful microbes in the gastrointestinal tract. Objectives: In the present study, we carried out an in vitro investigation and evaluated the antimicrobial activity of chitosan film forming solution incorporated with essential oils (CFs+EOs) against microbial strains including Staphylococcus aureus, Escherichia coli, Enterococcus faecium, Lactobacillus rahmnosus, Aspergillus niger and Alternaria alternate . Material and Methods: In three replicates, the minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) of different treatments including: 1- essential oils (EOs), 2- chitosan film solution (CFs), and 3-chitosan film solution enriched with EOs (CFs+EOs) were determined against above mentioned microbes. Results: The results indicated that the chitosan solution enriched with essential oils (CFs+EOs) is capable of inhibiting the bacterial and fungal growth even at the lowest concentrations. The MIC and MBC for all the antimicrobial agents against Escherichia coli and Staphylococcus aureus were very low compared to the concentrations needed to inhibit the growth of useful bacteria, Lactobacillus rahmnosu and Enterococcus faecium . The antifungal activity of chitosan was enhanced as the concentration of EOs increased in the film solution. Conclusion: Chitosan-EOs complexes are the promising candidate for novel contact antimicrobial agents that can be used in animal feeds.

Intestinal manipulation affects mucosal antimicrobial defense in a mouse model of postoperative ileus

PubMed Central

Hieggelke, Lena; Schneiker, Bianca; Lysson, Mariola; Stoffels, Burkhard; Nuding, Sabine; Wehkamp, Jan; Kikhney, Judith; Moter, Annette; Kalff, Joerg C.

2018-01-01

Aim To explore the effects of abdominal surgery and interleukin-1 signaling on antimicrobial defense in a model of postoperative ileus. Methods C57BL/6 and Interleukin-1 receptor type I (IL-1R1) deficient mice underwent intestinal manipulation to induce POI. Expression of mucosal IL-1α, IL-1β and IL-1R1 and several antimicrobial peptides and enzymes were measured by quantitative PCR or ELISA, western blotting or immunohistochemistry. Bacterial overgrowth was determined by fluorescent in-situ hybridization and counting of jejunal luminal bacteria. Translocation of aerobic and anaerobic bacteria into the intestinal wall, mesenteric lymph nodes, liver and spleen was determined by counting bacterial colonies on agar plates 48h after plating of tissue homogenates. Antimicrobial activity against E. coli and B. vulgatus was analyzed in total and cationic fractions of small bowel mucosal tissue homogenates by a flow cytometry-based bacterial depolarization assay. Results Jejunal bacterial overgrowth was detected 24h after surgery. At the same time point, but not in the early phase 3h after surgery, bacterial translocation into the liver and mesenteric lymph nodes was observed. Increased antimicrobial activity against E. coli was induced within early phase of POI. Basal antimicrobial peptide and enzyme gene expression was higher in the ileal compared to the jejunal mucosa. The expression of lysozyme 1, cryptdin 1, cryptdin 4 and mucin 2 were reduced 24h after surgery in the ileal mucosa and mucin 2 was also reduced in the jejunum. Postoperative IL-1α and IL-1β were increased in the postoperative mucosa. Deficiency of IL-1R1 affected the expression of antimicrobial peptides during homeostasis and POI. Conclusion Small bowel antimicrobial capacity is disturbed during POI which is accompanied by bacterial overgrowth and translocation. IL-1R1 is partially involved in the gene expression of mucosal antimicrobial peptides. Altered small bowel antimicrobial activity may contribute also to POI development and manifestation in patients undergoing abdominal surgery. PMID:29652914

Fractionation, amino acid profiles, antimicrobial and free radical scavenging activities of Citrullus lanatus seed protein.

PubMed

Dash, Priyanka; Ghosh, Goutam

2017-12-01

In the present study, a modified Osborne fractionation method was followed to isolate albumin (C alb ), globulin (C glo ), prolamin (C pro ) and glutelin (C glu ) successively from seeds of Citrullus lanatus (watermelon). This research work was undertaken to investigate the antimicrobial and antioxidant activities of isolated protein fractions of C. lanatus seed. Amino acid composition and molecular weight distribution were determined to establish their relationship with antimicrobial and antioxidant activity. Among all the fractions, C pro was found to be most effective against A. baumannii followed by C alb and C glo . The results showed that growth of inhibition of these protein fractions differ significantly from each other (p ≤ 0.05). In view of antioxidant potential, C glo exhibited strongest antioxidant capacity while C glu showed weakest antioxidant potential.

Composition, quality control, and antimicrobial activity of the essential oil of long-time stored dill (Anethum graveolens L.) seeds from Bulgaria.

PubMed

Jirovetz, Leopold; Buchbauer, Gerhard; Stoyanova, Albena S; Georgiev, Evgenii V; Damianova, Stanka T

2003-06-18

The essential oil of long-time stored seeds of dill (Anethum graveolens L.) from Bulgaria was analyzed by physicochemical methods, gas chromatography (GC), GC-mass spectrometry (MS) (achiral and chiral phases), and olfactometry, and its antimicrobial activity was tested by using different strains of microorganisms. More than 40 constituents of the essential dill oil, obtained from seeds stored for more than 35 years, could be identified as essential volatiles, responsible for the pleasant fresh (D-limonene) and spicy (D-carvone) odor of a high quality. As aroma impact compounds, D-carvone (50.1%) and D-limonene (44.1%) were found. Antimicrobial testings showed high activity of the essential A. graveolens oil against the mold Aspergillus niger and the yeasts Saccharomyces cerevisiae and Candida albicans.

Antimicrobial and antitumor activity of platinum and palladium complexes of novel spherical aramides nanoparticles containing flexibilizing linkages: structure-property relationship.

PubMed

Elhusseiny, Amel F; Hassan, Hammed H A M

2013-02-15

Square planar Pd (II) and octahedral Pt (IV) complexes with novel spherical aramides nanoparticles containing flexible linkages ligands have been synthesized and characterized using analytical and spectral techniques. The synthesized complexes have been tested for their antimicrobial activity using Kirby-Bauer disc diffusion method. The antitumor activity has been performed using liver carcinoma (HEPG2), breast carcinoma (MCF7) and colon carcinoma (HCT 116) cell lines. Palladium complexes of polyamides containing sulfones showed the highest potency as antibacterial and antifungal agents. Platinum complexes containing sulfone and ether flexible linkages and chloro groups exhibited high potency as antitumor and antimicrobial agents. The uniform sizes of these nanomaterials could find biological uses such as immune assay and other medical purposes. Copyright © 2012 Elsevier B.V. All rights reserved.

Antimicrobial activity of Arctium lappa constituents against microorganisms commonly found in endodontic infections.

PubMed

Pereira, Juliana Vianna; Bergamo, Débora Cristina Baldoqui; Pereira, José Odair; França, Suzelei de Castro; Pietro, Rosemeire Cristina Linhares Rodrigues; Silva-Sousa, Yara T Corrêa

2005-01-01

This study evaluated in vitro the antimicrobial activity of rough extracts from leaves of Arctium lappa and their phases. The following microorganisms, commonly found in the oral cavity, specifically in endodontic infections, were used: Enterococcus faecalis, Staphylococcus aureus, Pseudomonas aeruginosa, Bacillus subtilis and Candida albicans. The agar-diffusion method allowed detection of the hexanic phase as an inhibitor of microbial growth. Bioautographic assays identified antimicrobial substances in the extract. The results showed the existence, in the rough hexanic phase and in its fractions, of constituents that have retention factors (Rf) in three distinct zones, thereby suggesting the presence of active constituents with chemical structures of different polarities that exhibited specificity against the target microorganisms. It may be concluded that the Arctium lappa constituents exhibited a great microbial inhibition potential against the tested endodontic pathogens.

Effects of processing methods on composition and functionality of volatile components isolated from immature fruits of atemoya.

PubMed

Liu, Tai-Ti; Chao, Louis Kuo-Ping; Peng, Chi-Wei; Yang, Tsung-Shi

2016-07-01

Atemoya is one of the most important commercial fruits of the family Annonaceae. The immature fruits of atemoya amply produced from a fruit-thinning process is normally regarded as waste and discarded. This research aimed at studying antimicrobial, antioxidant, and anti-inflammatory activities of the essential oil (EO) isolated from the immature fruits to explore its potential application. The fruits were subjected to different drying methods: solar drying (SD), oven drying at 30°C (OD-30), and at 50°C (OD-50). The oven drying method gave a higher EO yield than the solar drying method. Spathulenol was the largest compound in the EO after the drying process. Antimicrobial effect was not affected by the different drying methods. Antioxidant activity of the EO was measured by DPPH, nitric oxide, and reducing power methods. The EOOD-50 exhibited a stronger antioxidant activity than EOSD and EOOD-30. The EO also showed an anti-inflammatory activity in a cell model. Copyright © 2016. Published by Elsevier Ltd.

Antioxidant, Antimicrobial and Cytotoxic Properties as Well as the Phenolic Content of the Extract from Hancornia speciosa Gomes

PubMed Central

Santos, Uilson P.; Campos, Jaqueline F.; Torquato, Heron Fernandes V.; Paredes-Gamero, Edgar Julian; Carollo, Carlos Alexandre; Estevinho, Leticia M.; de Picoli Souza, Kely

2016-01-01

Hancornia speciosa Gomes (Apocynaceae) is a fruit tree, popularly known as mangabeira, and it is widely distributed throughout Brazil. Several parts of the plant are used in folk medicine, and the leaf and bark extracts have anti-inflammatory, antihypertensive, antidiabetic, and antimicrobial properties. In this study, we investigated the chemical composition of the ethanolic extract of Hancornia speciosa leaves (EEHS) and its antioxidant, antimicrobial, and cytotoxic activities as well as the mechanisms involved in cell death. The chemical compounds were identified by liquid chromatography coupled to mass spectrometry (LC-MS/MS). The antioxidant activity of the EEHS was investigated using the method that involves the scavenging of 2,2-diphenyl-1-picrylhydrazyl free radicals as well as the inhibition of oxidative hemolysis and lipid peroxidation induced by 2,2’-azobis (2-amidinopropane) in human erythrocytes. The antimicrobial activity was determined by calculating the minimum inhibitory concentration, minimum bactericidal concentration, minimum fungicidal concentration, and zone of inhibition. Kasumi-1 leukemic cells were used to assess the cytotoxic activity and mechanisms involved in cell death promoted by the EEHS. The chemical compounds identified were quinic acid, chlorogenic acid, catechin, rutin, isoquercitrin, kaempferol-rutinoside, and catechin-pentoside. The EEHS demonstrated antioxidant activity via the sequestration of free radicals, inhibition of hemolysis, and inhibition of lipid peroxidation in human erythrocytes incubated with an oxidizing agent. The antimicrobial activity was observed against American Type Culture Collection (ATCC) and hospital strains of bacteria and fungi, filamentous fungi and dermatophytes. The cytotoxic activity of the EEHS was induced by apoptosis, reduction of the mitochondrial membrane potential, and activation of cathepsins. Together, these results indicate the presence of phenolic compounds and flavonoids in the EEHS and that their antioxidant, antimicrobial, and cytotoxic activities in acute myeloid leukemia cells are mediated by apoptosis. PMID:27907185

Antioxidant, antimicrobial, antiparasitic, and cytotoxic properties of various Brazilian propolis extracts

PubMed Central

Barreto, Gabriele de Abreu; Costa, Samantha Serra; Andrade, Luciana Nalone; Amaral, Ricardo Guimarães; Carvalho, Adriana Andrade; Padilha, Francine Ferreira; Barbosa, Josiane Dantas Viana

2017-01-01

Propolis is known for its biological properties and its preparations have been continuously investigated in an attempt to solve the problem of their standardization, an issue that limits the use of propolis in food and pharmaceutical industries. The aim of this study was to evaluate in vitro antioxidant, antimicrobial, antiparasitic, and cytotoxic effects of extracts of red, green, and brown propolis from different regions of Brazil, obtained by ethanolic and supercritical extraction methods. We found that propolis extracts obtained by both these methods showed concentration-dependent antioxidant activity. The extracts obtained by ethanolic extraction showed higher antioxidant activity than that shown by the extracts obtained by supercritical extraction. Ethanolic extracts of red propolis exhibited up to 98% of the maximum antioxidant activity at the highest extract concentration. Red propolis extracts obtained by ethanolic and supercritical methods showed the highest levels of antimicrobial activity against several bacteria. Most extracts demonstrated antimicrobial activity against Staphylococcus aureus. None of the extracts analyzed showed activity against Escherichia coli or Candida albicans. An inhibitory effect of all tested ethanolic extracts on the growth of Trypanosoma cruzi Y strain epimastigotes was observed in the first 24 h. However, after 96 h, a persistent inhibitory effect was detected only for red propolis samples. Only ethanolic extracts of red propolis samples R01Et.B2 and R02Et.B2 showed a cytotoxic effect against all four cancer cell lines tested (HL-60, HCT-116, OVCAR-8, and SF-295), indicating that red propolis extracts have great cytotoxic potential. The biological effects of ethanolic extracts of red propolis revealed in the present study suggest that red propolis can be a potential alternative therapeutic treatment against Chagas disease and some types of cancer, although high activity of red propolis in vitro needs to be confirmed by future in vivo investigations. PMID:28358806

Antioxidant, antimicrobial, antiparasitic, and cytotoxic properties of various Brazilian propolis extracts.

PubMed

Dantas Silva, Rejane Pina; Machado, Bruna Aparecida Souza; Barreto, Gabriele de Abreu; Costa, Samantha Serra; Andrade, Luciana Nalone; Amaral, Ricardo Guimarães; Carvalho, Adriana Andrade; Padilha, Francine Ferreira; Barbosa, Josiane Dantas Viana; Umsza-Guez, Marcelo Andres

2017-01-01

Propolis is known for its biological properties and its preparations have been continuously investigated in an attempt to solve the problem of their standardization, an issue that limits the use of propolis in food and pharmaceutical industries. The aim of this study was to evaluate in vitro antioxidant, antimicrobial, antiparasitic, and cytotoxic effects of extracts of red, green, and brown propolis from different regions of Brazil, obtained by ethanolic and supercritical extraction methods. We found that propolis extracts obtained by both these methods showed concentration-dependent antioxidant activity. The extracts obtained by ethanolic extraction showed higher antioxidant activity than that shown by the extracts obtained by supercritical extraction. Ethanolic extracts of red propolis exhibited up to 98% of the maximum antioxidant activity at the highest extract concentration. Red propolis extracts obtained by ethanolic and supercritical methods showed the highest levels of antimicrobial activity against several bacteria. Most extracts demonstrated antimicrobial activity against Staphylococcus aureus. None of the extracts analyzed showed activity against Escherichia coli or Candida albicans. An inhibitory effect of all tested ethanolic extracts on the growth of Trypanosoma cruzi Y strain epimastigotes was observed in the first 24 h. However, after 96 h, a persistent inhibitory effect was detected only for red propolis samples. Only ethanolic extracts of red propolis samples R01Et.B2 and R02Et.B2 showed a cytotoxic effect against all four cancer cell lines tested (HL-60, HCT-116, OVCAR-8, and SF-295), indicating that red propolis extracts have great cytotoxic potential. The biological effects of ethanolic extracts of red propolis revealed in the present study suggest that red propolis can be a potential alternative therapeutic treatment against Chagas disease and some types of cancer, although high activity of red propolis in vitro needs to be confirmed by future in vivo investigations.

Analysis of antimicrobial, antifungal and antioxidant activities of Juniperus excelsa M. B subsp. Polycarpos (K. Koch) Takhtajan essential oil

PubMed Central

Moein, M. R.; Ghasemi, Y.; Moein, S.; Nejati, M.

2010-01-01

Juniperus excelsa M.B subsp. Polycarpos (K.Koch), collected from south of Iran, was subjected to hydrodistillation using clevenger apparatus to obtain essential oil. The essential was analyzed by gas chromatography/mass spectrometry (GC/MS) and studied for antimicrobial, antifungal and antioxidant activities. The results indicated α-pinene (67.71%) as the major compound and α-cedral (11.5%), δ3-carene (5.19%) and limonene (4.41%) in moderate amounts. Antimicrobial tests were carried out using disk diffusion method, followed by the measurement of minimum inhibitory concentration (MIC). All the Gram positive and Gram negative bacteria were susceptible to essential oil. The oil showed radical scavenging and antioxidant effects. PMID:21808554

In Vitro Antimicrobial Susceptibility of Brachyspira pilosicoli Isolates from Humans

PubMed Central

Brooke, C. J.; Hampson, D. J.; Riley, T. V.

2003-01-01

The in vitro antimicrobial susceptibility of the anaerobic intestinal spirochete Brachyspira pilosicoli was investigated by an agar dilution method. Human (n = 123) and porcine (n = 16) isolates were susceptible to metronidazole, ceftriaxone, meropenem, tetracycline, moxifloxacin, and chloramphenicol; erythromycin and ciprofloxacin were not active. Resistance to amoxicillin and clindamycin varied. Amoxicillin susceptibility was restored by clavulanic acid. PMID:12821498

The in vitro Antimicrobial Activity and Chemometric Modelling of 59 Commercial Essential Oils against Pathogens of Dermatological Relevance.

PubMed

Orchard, Ané; Sandasi, Maxleene; Kamatou, Guy; Viljoen, Alvaro; van Vuuren, Sandy

2017-01-01

This study reports on the inhibitory concentration of 59 commercial essential oils recommended for dermatological conditions, and identifies putative compounds responsible for antimicrobial activity. Essential oils were investigated for antimicrobial activity using minimum inhibitory concentration assays. Ten essential oils were identified as having superior antimicrobial activity. The essential oil compositions were determined using gas chromatography coupled to mass spectrometry and the data analysed with the antimicrobial activity using multivariate tools. Orthogonal projections to latent structures models were created for seven of the pathogens. Eugenol was identified as the main biomarker responsible for antimicrobial activity in the majority of the essential oils. The essential oils mostly displayed noteworthy antimicrobial activity, with five oils displaying broad-spectrum activity against the 13 tested micro-organisms. The antimicrobial efficacies of the essential oils highlight their potential in treating dermatological infections and through chemometric modelling, bioactive volatiles have been identified. © 2017 Wiley-VHCA AG, Zurich, Switzerland.

Phytochemical Constituents and Antimicrobial Activity of the Ethanol and Chloroform Crude Leaf Extracts of Spathiphyllum cannifolium (Dryand. ex Sims) Schott.

PubMed

Dhayalan, Arunachalam; Gracilla, Daniel E; Dela Peña, Renato A; Malison, Marilyn T; Pangilinan, Christian R

2018-01-01

The study investigated the medicinal properties of Spathiphyllum cannifolium (Dryand. ex Sims) Schott as a possible source of antimicrobial compounds. The phytochemical constituents were screened using qualitative methods and the antibacterial and antifungal activities were determined using agar well diffusion method. One-way analysis of variance and Fisher's least significant difference test were used. The phytochemical screening showed the presence of sterols, flavonoids, alkaloids, saponins, glycosides, and tannins in both ethanol and chloroform leaf extracts, but triterpenes were detected only in the ethanol leaf extract. The antimicrobial assay revealed that the chloroform leaf extract inhibited Candida albicans, Escherichia coli, Staphylococcus aureus, Bacillus subtilis, and Pseudomonas aeruginosa , whereas the ethanol leaf extract inhibited E. coli , S. aureus , and B. subtilis only. The ethanol and chloroform leaf extracts exhibited the highest zone of inhibition against B. subtilis . The antifungal assay showed that both the leaf extracts have no bioactivity against Aspergillus niger and C. albicans . Results suggest that chloroform is the better solvent for the extraction of antimicrobial compounds against the test organisms used in this study. Findings of this research will add new knowledge in advancing drug discovery and development in the Philippines.

Comparison of methods to detect the in vitro activity of silver nanoparticles (AgNP) against multidrug resistant bacteria.

PubMed

Cavassin, Emerson Danguy; de Figueiredo, Luiz Francisco Poli; Otoch, José Pinhata; Seckler, Marcelo Martins; de Oliveira, Roberto Angelo; Franco, Fabiane Fantinelli; Marangoni, Valeria Spolon; Zucolotto, Valtencir; Levin, Anna Sara Shafferman; Costa, Silvia Figueiredo

2015-10-05

Multidrug resistant microorganisms are a growing challenge and new substances that can be useful to treat infections due to these microorganisms are needed. Silver nanoparticle may be a future option for treatment of these infections, however, the methods described in vitro to evaluate the inhibitory effect are controversial. This study evaluated the in vitro activity of silver nanoparticles against 36 susceptible and 54 multidrug resistant Gram-positive and Gram-negative bacteria from clinical sources. The multidrug resistant bacteria were oxacilin-resistant Staphylococcus aureus, vancomycin-resistant Enterococcus spp., carbapenem- and polymyxin B-resistant A. baumannii, carbapenem-resistant P. aeruginosa and carbapenem-resistant Enterobacteriaceae. We analyzed silver nanoparticles stabilized with citrate, chitosan and polyvinyl alcohol and commercial silver nanoparticle. Silver sulfadiazine and silver nitrate were used as control. Different methods were used: agar diffusion, minimum inhibitory concentration, minimum bactericidal concentration and time-kill. The activity of AgNPs using diffusion in solid media and the MIC methods showed similar effect against MDR and antimicrobial-susceptible isolates, with a higher effect against Gram-negative isolates. The better results were achieved with citrate and chitosan silver nanoparticle, both with MIC90 of 6.75 μg mL(-1), which can be due the lower stability of these particles and, consequently, release of Ag(+) ions as revealed by X-ray diffraction (XRD). The bactericidal effect was higher against antimicrobial-susceptible bacteria. It seems that agar diffusion method can be used as screening test, minimum inhibitory concentration/minimum bactericidal concentration and time kill showed to be useful methods. The activity of commercial silver nanoparticle and silver controls did not exceed the activity of the citrate and chitosan silver nanoparticles. The in vitro inhibitory effect was stronger against Gram-negative than Gram-positive, and similar against multidrug resistant and susceptible bacteria, with best result achieved using citrate and chitosan silver nanoparticles. The bactericidal effect of silver nanoparticle may, in the future, be translated into important therapeutic and clinical options, especially considering the shortage of new antimicrobials against the emerging antimicrobial resistant microorganisms, in particular against Gram-negative bacteria.

Biosynthesis and Characterization of AgNPs–Silk/PVA Film for Potential Packaging Application

PubMed Central

Tao, Gang; Cai, Rui; Wang, Yejing; Song, Kai; Guo, Pengchao; Zhao, Ping; Zuo, Hua; He, Huawei

2017-01-01

Bionanocomposite packaging materials have a bright future for a broad range of applications in the food and biomedical industries. Antimicrobial packaging is one of the bionanocomposite packaging materials. Silver nanoparticle (AgNP) is one of the most attractive antimicrobial agents for its broad spectrum of antimicrobial activity against microorganisms. However, the traditional method of preparing AgNPs-functionalized packaging material is cumbersome and not environmentally friendly. To develop an efficient and convenient biosynthesis method to prepare AgNPs-modified bionanocomposite material for packaging applications, we synthesized AgNPs in situ in a silk fibroin solution via the reduction of Ag+ by the tyrosine residue of fibroin, and then prepared AgNPs–silk/poly(vinyl alcohol) (PVA) composite film by blending with PVA. AgNPs were synthesized evenly on the surface or embedded in the interior of silk/PVA film. The prepared AgNPs–silk/PVA film exhibited excellent mechanical performance and stability, as well as good antibacterial activity against both Gram-negative and Gram-positive bacteria. AgNPs–silk/PVA film offers more choices to be potentially applied in the active packaging field. PMID:28773026

Antimicrobial activity of some essential oils against oral multidrug-resistant Enterococcus faecalis in both planktonic and biofilm state

PubMed Central

Benbelaïd, Fethi; Khadir, Abdelmounaïm; Abdoune, Mohamed Amine; Bendahou, Mourad; Muselli, Alain; Costa, Jean

2014-01-01

Objective To evaluate some essential oils in treatment of intractable oral infections, principally caused by biofilm of multidrug-resistant Enterococcus faecalis (E. faecalis), such as persistent endodontic infections in which their treatment exhibits a real challenge for dentists. Methods Ten chemically analyzed essential oils by gas chromatography-mass spectrometry were evaluated for antimicrobial activity against sensitive and resistant clinical strains of E. faecalis in both planktonic and biofilm state using two methods, disk diffusion and broth micro-dilution. Results Studied essential oils showed a good antimicrobial activity and high ability in E. faecalis biofilm eradication, whether for sensitive or multidrug-resistant strains, especially those of Origanum glandulosum and Thymbra capitata with interesting minimum inhibitory concentration, biofilm inhibitory concentration, and biofilm eradication concentration values which doesn't exceed 0.063%, 0.75%, and 1.5%, respectively. Conclusions Findings of this study indicate that essential oils extracted from aromatic plants can be used in treatment of intractable oral infections, especially caused by biofilm of multidrug-resistant E. faecalis. PMID:25182948

Antimicrobial and Antibiofilm Activities of Citrus Water-Extracts Obtained by Microwave-Assisted and Conventional Methods.

PubMed

Caputo, Leonardo; Quintieri, Laura; Cavalluzzi, Maria Maddalena; Lentini, Giovanni; Habtemariam, Solomon

2018-06-17

Citrus pomace is a huge agro-food industrial waste mostly composed of peels and traditionally used as compost or animal feed. Owing to its high content of compounds beneficial to humans (e.g., flavonoids, phenol-like acids, and terpenoids), citrus waste is increasingly used to produce valuable supplements, fragrance, or antimicrobials. However, such processes require sustainable and efficient extraction strategies by solvent-free techniques for environmentally-friendly good practices. In this work, we evaluated the antimicrobial and antibiofilm activity of water extracts of three citrus peels (orange, lemon, and citron) against ten different sanitary relevant bacteria. Both conventional extraction methods using hot water (HWE) and microwave-assisted extraction (MAE) were used. Even though no extract fully inhibited the growth of the target bacteria, these latter (mostly pseudomonads) showed a significant reduction in biofilm biomass. The most active extracts were obtained from orange and lemon peel by using MAE at 100 °C for 8 min. These results showed that citrus peel water infusions by MAE may reduce biofilm formation possibly enhancing the susceptibility of sanitary-related bacteria to disinfection procedures.

Detailed solvent, structural, quantum chemical study and antimicrobial activity of isatin Schiff base

NASA Astrophysics Data System (ADS)

Brkić, Dominik R.; Božić, Aleksandra R.; Marinković, Aleksandar D.; Milčić, Miloš K.; Prlainović, Nevena Ž.; Assaleh, Fathi H.; Cvijetić, Ilija N.; Nikolić, Jasmina B.; Drmanić, Saša Ž.

2018-05-01

The ratios of E/Z isomers of sixteen synthesized 1,3-dihydro-3-(substituted phenylimino)-2H-indol-2-one were studied using experimental and theoretical methodology. Linear solvation energy relationships (LSER) rationalized solvent influence of the solvent-solute interactions on the UV-Vis absorption maxima shifts (νmax) of both geometrical isomers using the Kamlet-Taft equation. Linear free energy relationships (LFER) in the form of single substituent parameter equation (SSP) was used to analyze substituent effect on pKa, NMR chemical shifts and νmax values. Electron charge density was obtained by the use of Quantum Theory of Atoms in Molecules, i.e. Bader's analysis. The substituent and solvent effect on intramolecular charge transfer (ICT) were interpreted with the aid of time-dependent density functional (TD-DFT) method. Additionally, the results of TD-DFT calculations quantified the efficiency of ICT from the calculated charge-transfer distance (DCT) and amount of transferred charge (QCT). The antimicrobial activity was evaluated using broth microdilution method. 3D QSAR modeling was used to demonstrate the influence of substituents effect as well as molecule geometry on antimicrobial activity.

Rhanterium epapposum Oliv. essential oil: Chemical composition and antimicrobial, insect-repellent and anticholinesterase activities.

PubMed

Demirci, Betul; Yusufoglu, Hasan Soliman; Tabanca, Nurhayat; Temel, Halide Edip; Bernier, Ulrich R; Agramonte, Natasha M; Alqasoumi, Saleh Ibrahim; Al-Rehaily, Adnan Jathlan; Başer, Kemal Husnu Can; Demirci, Fatih

2017-07-01

The essential oil (EO) of the aerial parts of Rhanterium epapposum Oliv. (Asteraceae), was obtained by hydrodistillation. The oil was subsequently analyzed by both GC-FID and GC-MS, simultaneously. Forty-five components representing 99.2% of the oil composition were identified. The most abundant compounds were camphene (38.5%), myrcene (17.5%), limonene (10.1%) and α-pinene (8.7%). Referring to the ethnobotanical utilization, an insecticidal assay was performed, where the oil repelled the yellow fever mosquito Aedes aegypti L. at a minimum effective dose (MED of 0.035 ± 0.010 mg/cm 2 ) compared to the positive control DEET (MED of 0.015 ± 0.004 mg/cm 2 ). Additionally, the in vitro antimicrobial activity against a panel of pathogens was determined using a microdilution method. The acetyl- and butyrylcholine esterase inhibitory activities were measured using the colorimetric Ellman method. The bioassay results showed that the oil was rather moderate in antimicrobial and cholinesterase inhibitions when compared to the standard compounds.

Preparation of SiO2@Ag Composite Nanoparticles and Their Antimicrobial Activity.

PubMed

Qin, Rui; Li, Guian; Pan, Liping; Han, Qingyan; Sun, Yan; He, Qiao

2017-04-01

At normal atmospheric temperature, the modified sol–gel method was employed to synthesize SiO2 nanospheres (SiO2 NSs) whose average size was about 352 nm. Silver nanoparticles (Ag NPs) were uniformly distributed on the surface of SiO2 nanospheres (SiO2 NSs) by applying chemical reduction method at 95 °C and the size of silver nanoparticles (Ag NPs) could be controlled by simply tuning the reaction time and the concentration of sodium citrate. Besides, the size, morphology, structure and optical absorption properties of SiO2@Ag composite nanoparticles were measured and characterized by laser particle size analyzer (LPSA), transmission electron microscope (TEM), scanning electron microscope (SEM), X-ray diffraction (XRD) and ultraviolet visible absorption spectrometer (UV-Vis), respectively. Furthermore, antimicrobial effect experiments that against gram-negative bacteria (E. coli) and gram-positive bacteria (S. aureus) were carried out to characterize the antibacterial activity of synthesized SiO2@Ag composite nanoparticles. The results show that the prepared SiO2@Ag composite nanoparticles have strong antimicrobial activity, which is associated with the size of silver nanoparticles.

Composition, Cytotoxic and Antimicrobial Activities of Satureja intermedia C.A.Mey Essential Oil.

PubMed

Sharifi-Rad, Javad; Sharifi-Rad, Mehdi; Hoseini-Alfatemi, Seyedeh Mahsan; Iriti, Marcello; Sharifi-Rad, Majid; Sharifi-Rad, Marzieh

2015-08-03

In this study, the essential oil (EO) constituents from the aerial parts of Satureja intermedia C.A.Mey were detected by GC and GC/MS. The antimicrobial activity of EO on oral pathogens and its cytotoxicity to human cancer cells were determined by the microbroth dilution method and the crystal violet staining method, respectively. Thirty-nine compounds were identified and the main EO constituents were γ-terpinene (37.1%), thymol (30.2%), p-cymene (16.2%), limonene (3.9%), α-terpinene (3.3%), myrcene (2.5%), germacrene B (1.4%), elemicine (1.1%) and carvacrol (0.5%). The S. intermedia EO showed a concentration-dependent decrease in viability of Hep-G2 (hepatocellular carcinoma) and MCF-7 (breast adenocarcinoma) human cancer cell lines (p < 0.05). Antimicrobial screening of S. intermedia EO demonstrated slight antibacterial and antifungal activities against Streptococcus mutants, S. salivarius, Enterococcus faecalis, Staphylococcus aureus, Candida albicans and C. glabrata. Further preclinical studies are needed to assess the efficacy and safety of S. intermedia EO as a new promising anticancer agent.

Composition, Cytotoxic and Antimicrobial Activities of Satureja intermedia C.A.Mey Essential Oil

PubMed Central

Sharifi-Rad, Javad; Sharifi-Rad, Mehdi; Hoseini-Alfatemi, Seyedeh Mahsan; Iriti, Marcello; Sharifi-Rad, Majid; Sharifi-Rad, Marzieh

2015-01-01

In this study, the essential oil (EO) constituents from the aerial parts of Satureja intermedia C.A.Mey were detected by GC and GC/MS. The antimicrobial activity of EO on oral pathogens and its cytotoxicity to human cancer cells were determined by the microbroth dilution method and the crystal violet staining method, respectively. Thirty-nine compounds were identified and the main EO constituents were γ-terpinene (37.1%), thymol (30.2%), p-cymene (16.2%), limonene (3.9%), α-terpinene (3.3%), myrcene (2.5%), germacrene B (1.4%), elemicine (1.1%) and carvacrol (0.5%). The S. intermedia EO showed a concentration-dependent decrease in viability of Hep-G2 (hepatocellular carcinoma) and MCF-7 (breast adenocarcinoma) human cancer cell lines (p < 0.05). Antimicrobial screening of S. intermedia EO demonstrated slight antibacterial and antifungal activities against Streptococcus mutants, S. salivarius, Enterococcus faecalis, Staphylococcus aureus, Candida albicans and C. glabrata. Further preclinical studies are needed to assess the efficacy and safety of S. intermedia EO as a new promising anticancer agent. PMID:26247936

Biosynthesis and Characterization of AgNPs-Silk/PVA Film for Potential Packaging Application.

PubMed

Tao, Gang; Cai, Rui; Wang, Yejing; Song, Kai; Guo, Pengchao; Zhao, Ping; Zuo, Hua; He, Huawei

2017-06-17

Bionanocomposite packaging materials have a bright future for a broad range of applications in the food and biomedical industries. Antimicrobial packaging is one of the bionanocomposite packaging materials. Silver nanoparticle (AgNP) is one of the most attractive antimicrobial agents for its broad spectrum of antimicrobial activity against microorganisms. However, the traditional method of preparing AgNPs-functionalized packaging material is cumbersome and not environmentally friendly. To develop an efficient and convenient biosynthesis method to prepare AgNPs-modified bionanocomposite material for packaging applications, we synthesized AgNPs in situ in a silk fibroin solution via the reduction of Ag⁺ by the tyrosine residue of fibroin, and then prepared AgNPs-silk/poly(vinyl alcohol) (PVA) composite film by blending with PVA. AgNPs were synthesized evenly on the surface or embedded in the interior of silk/PVA film. The prepared AgNPs-silk/PVA film exhibited excellent mechanical performance and stability, as well as good antibacterial activity against both Gram-negative and Gram-positive bacteria. AgNPs-silk/PVA film offers more choices to be potentially applied in the active packaging field.

Antimicrobial activities of commercial essential oils and their components against food-borne pathogens and food spoilage bacteria

PubMed Central

Mith, Hasika; Duré, Rémi; Delcenserie, Véronique; Zhiri, Abdesselam; Daube, Georges; Clinquart, Antoine

2014-01-01

This study was undertaken to determine the in vitro antimicrobial activities of 15 commercial essential oils and their main components in order to pre-select candidates for potential application in highly perishable food preservation. The antibacterial effects against food-borne pathogenic bacteria (Listeria monocytogenes, Salmonella Typhimurium, and enterohemorrhagic Escherichia coli O157:H7) and food spoilage bacteria (Brochothrix thermosphacta and Pseudomonas fluorescens) were tested using paper disk diffusion method, followed by determination of minimum inhibitory (MIC) and bactericidal (MBC) concentrations. Most of the tested essential oils exhibited antimicrobial activity against all tested bacteria, except galangal oil. The essential oils of cinnamon, oregano, and thyme showed strong antimicrobial activities with MIC ≥ 0.125 μL/mL and MBC ≥ 0.25 μL/mL. Among tested bacteria, P. fluorescens was the most resistant to selected essential oils with MICs and MBCs of 1 μL/mL. The results suggest that the activity of the essential oils of cinnamon, oregano, thyme, and clove can be attributed to the existence mostly of cinnamaldehyde, carvacrol, thymol, and eugenol, which appear to possess similar activities against all the tested bacteria. These materials could be served as an important natural alternative to prevent bacterial growth in food products. PMID:25473498

Preparation and Characterization of Ternary Antimicrobial Films of β-Cyclodextrin/Allyl Isothiocyanate/Polylactic Acid for the Enhancement of Long-Term Controlled Release

PubMed Central

Wang, Jinpeng; Qiu, Chao; Narsimhan, Ganesan; Jin, Zhengyu

2017-01-01

Allyl isothiocyanate (AITC) are natural essential oil components that have outstanding antimicrobial activities. However, low water solubility, high volatility, and easy degradation by heat, restricting their application in food packing industry. Development of the inclusion complex of β-cyclodextrin/AITC (β-CD/AITC) is a promising solution. Furthermore, the incorporation of β-CD/AITC complex into polylactic acid (PLA) films would be an attractive method to develop food antimicrobial materials. The aim of this study was to evaluate the enhancement in physicochemical properties, antimicrobial activities, and controlled release of β-CD/AITC from such films. The addition of β-CD/AITC significantly increased the flexibility and thermal stability of films. The Fourier transform infrared (FTIR) results revealed that the interactions between β-CD/AITC and PLA films occurred. The controlled release of AITC encapsulated in β-CD was significantly affected by relative humidity and temperature. The PLA films containing β-CD/AITC can be applied as an effective antimicrobial packing material for food and non-food applications. PMID:29053573

Biologically active and thermally stable polymeric Schiff base and its metal polychelates: Their synthesis and spectral aspects

NASA Astrophysics Data System (ADS)

Rasool, Raza; Hasnain, Sumaiya

2015-09-01

New metal polychelates of Mn(II), Co(II), Ni(II), Cu(II) and Zn(II) obtained by the interaction of metal acetates with polymeric Schiff base containing formaldehyde and piperazine, have been investigated. Structural and spectroscopic properties have been evaluated by elemental analysis, FT-IR and 1H-NMR. Geometry of the chelated polymers was confirmed by magnetic susceptibility measurements, UV-Visible spectroscopy and Electron Spin Resonance. The molecular weight of the polymer was determined by gel permeation chromatography (GPC). Thermogravimetric analysis indicated that metal polychelates were more thermally stable than their corresponding ligand. All compounds were screened for their antimicrobial activities against Escherichia coli, Staphylococcus aureus, Bacillus subtilis, (bacteria) and Candida albicans, Microsporum canis, Cryptococcus neoformans (fungi) by agar well diffusion method. Interestingly, the polymeric Schiff base was found to be antimicrobial in nature but less effective as compared to the metal polychelates. On the basis of thermal and antimicrobial behavior, these polymers hold potential applications as thermally resistant antimicrobial and antifouling coating materials as well as antimicrobial packaging materials.

Antimicrobial Peptides of Meat Origin - An In silico and In vitro Analysis.

PubMed

Keska, Paulina; Stadnik, Joanna

2017-01-01

The aim of this study was to evaluate the antimicrobial activity of meat protein-derived peptides against selected Gram-positive and Gram-negative bacteria. The in silico and in vitro approach was combined to determine the potency of antimicrobial peptides derived from pig (Sus scrofa) and cow (Bos taurus) proteins. The in silico studies consisted of an analysis of the amino acid composition of peptides obtained from the CAMPR database, their molecular weight and other physicochemical properties (isoelectric point, molar extinction coefficient, instability index, aliphatic index, hydropathy index and net charge). The degree of similarity was estimated between the antimicrobial peptide sequences derived from the slaughtered animals and the main meat proteins. Antimicrobial activity of peptides isolated from dry-cured meat products was analysed (in vitro) against two strains of pathogenic bacteria using the disc diffusion method. There was no evidence of growthinhibitory properties of peptides isolated from dry-cured meat products against Escherichia coli K12 ATCC 10798 and Staphylococcus aureus ATCC 25923. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Nanostructures as promising tools for delivery of antimicrobial peptides.

PubMed

Brandelli, A

2012-07-01

Antimicrobial peptides have been extensively investigated for their potential applications as therapeutics and food biopreservatives. The antimicrobial activity may be impaired by the susceptibility for proteolytic degradation and undesirable interactions of the antimicrobial peptide in the biological environment. Development of nanostructures for entrapment and delivery of antimicrobial peptides may represent an alternative to the direct application of these substances. Lipid nanovesicles have been developed for encapsulation of antimicrobial peptides. Phosphatidylcholine is often employed in liposome manufacture, which is mostly achieved by the thin-film hydration method. Nanofibers may allow different physical modes of drug loading, including direct adsorption on the nanofiber surface or the assembly of drug-loaded nanoparticles. Self-assembled peptides reveal attractive features as nanostructures for applications in drug delivery and promising as antimicrobial agent for treatment of brain infections. Magnetic nanoparticles and nanotubules are also potential structures for entrapment of antimicrobial peptides. Nanoparticles can be also chemically modified with specific cell surface ligands to enhance cell adhesion and site specific delivery. This article reviews the most important nanostructures as promising tools for peptide delivery systems.

Evaluation of phytochemical content, antimicrobial, cytotoxic and antitumor activities of extract from Rumex hastatus D. Don roots.

PubMed

Sahreen, Sumaira; Khan, Muhammad Rashid; Khan, Rahmat Ali; Hadda, Taibi Ben

2015-07-03

Being a part of Chinese as well as ayurdic herbal system, roots of Rumex hastatus D. Don (RH) is highly medicinal, used to regulated blood pressure. It is also reported that the plant is diuretic, laxative, tonic, used against microbial skin diseases, bilious complaints and jaundice. The present study is conducted to evaluate phytochemical, antimicrobial, antitumor and cytotoxic activities of extract obtained from R. hastatus roots. RH roots were powdered and extracted with methanol to get crude extract. Crude extract was further fractioned on the basis of increasing polarity, with n-hexane (HRR), chloroform (CRR), ethyl acetate (ERR), n-butanol (BRR) and residual aqueous fraction (ARR). Methanol extract and its derived fractions were subjected to phytochemical screening and assayed for antibacterial activities via agar well diffusion method. Antifungal activities were checked through agar tube dilution method whereas potato disc assay was employed for the determination of antitumor activity. On the other hand cytotoxic activities were conducted using brine shrimps procedures. The results obtained from phytochemical analysis indicate the presence of alkaloids, anthraquinones, flavonoids and saponins in all the fractions. Most of the plant fractions showed substantial antimicrobial activities, which is in accordance with the spacious use of tested plant samples in primary healthcare center. Fractions of R. hastatus roots for cytotoxicity were tested as an effective cytotoxic was found as BRR > MRR > CRR > ARR > ERR > HRR. Ranking order of fractions of R. hastatus roots for effective antitumor screening was found as MRR > BRR > ARR > CRR > ERR > HRR. These results showed that R. hastatus appeared as an important source for the discovery of new antimicrobial drugs and antitumor agents; verify its traditional uses and its exploitation as therapeutic agent.

Preparation and characterization of iron oxide magnetic nanoparticles functionalized by nisin.

PubMed

Gruskiene, Ruta; Krivorotova, Tatjana; Staneviciene, Ramune; Ratautas, Dalius; Serviene, Elena; Sereikaite, Jolanta

2018-05-08

Nisin is a known bacteriocin approved as a food additive for food preservation. It exhibits a wide spectrum antimicrobial activity against Gram-positive bacteria. Iron oxide magnetic nanoparticles were synthesized and characterized by X-ray diffraction method. A main part of iron oxide nanoparticles was found to be maghemite though a small quantity of magnetite could also be present. Magnetic nanoparticles were stabilized by citric, ascorbic, gallic or glucuronic acid coating. Stable iron oxide magnetic nanoparticles were functionalized by nisin using a simple and low cost adsorption method. Nisin loading was confirmed by FT-IR spectra, thermogravimetric analysis, dynamic light scattering and atomic force microscopy methods. Nisin-loaded iron oxide magnetic nanoparticles were stable at least six weeks as judged by the measurements of zeta-potential and hydrodynamic diameter. The antimicrobial activity of nisin-loaded iron oxide magnetic nanoparticles was demonstrated toward Gram-positive bacteria. Functionalized nanoparticles could therefore find the application as antimicrobials in innovative and emerging technologies based on the magnetic field. Copyright © 2018 Elsevier B.V. All rights reserved.

Tuned apatitic materials: Synthesis, characterization and potential antimicrobial applications

NASA Astrophysics Data System (ADS)

Fierascu, Irina; Fierascu, Radu Claudiu; Somoghi, Raluca; Ion, Rodica Mariana; Moanta, Adriana; Avramescu, Sorin Marius; Damian, Celina Maria; Ditu, Lia Mara

2018-04-01

Inorganic antimicrobial materials can be viable for multiple applications (related to its use for new buildings with special requirements related to microbiological loading, such as hospital buildings and for consolidation of cultural heritage constructions); also the use of substituted hydroxyapatites for protection of stone artefacts against environmental factors (acidic rain) and biodeterioration it's an option to no longer use of toxic substances. This paper presents methods of synthesis and characterization of the material from the point of view of the obtained structures and final applications. The materials were characterized in terms of composition and morphology (using X-ray Diffraction, X-ray Fluorescence, Inductively coupled plasma-atomic emission spectrometry, Fourier Transform Infrared Spectroscopy, X-ray Photoelectron Spectroscopy, Surface area and pore size determination). Antimicrobial activity was tested against filamentous fungi strains and pathogenic bacteria strains, using both spot on lawn qualitative method (on agar medium) and serial microdilution quantitative method (in broth medium). Further, it was evaluated the anti-biofilm activity of the tested samples toward the most important microbial strains implicated in biofilm development, using crystal violet stained biofilms microtiter assay, followed by spectrophotometric quantitative evaluation.

Chemical composition and antimicrobial activity of the essential oils from the gum of Turkish pistachio (Pistacia vera L.).

PubMed

Alma, Mehmet Hakki; Nitz, Siegfried; Kollmannsberger, Hubert; Digrak, Metin; Efe, Fatih Tuncay; Yilmaz, Necmettin

2004-06-16

The essential oil from the gum of Pistachio (Pistacia vera L. (Anacardiaceae)) grown in Turkey was obtained by the hydro-distillation method, and its chemical composition was analyzed by GC and GC-MS. Moreover, the antimicrobial activities of the oil against the growth of 13 bacteria and 3 pathogenic yeasts were evaluated using the agar-disk diffusion and minimum inhibitory concentration (MIC) methods. The results showed that the essential oil contained about 89.67% monoterpenes, 8.1% oxygenated monoterpenes and 1.2% diterpenes. alpha-Pinene (75.6%), beta-pinene (9.5%), trans-verbenol (3.0%), camphene (1.4%), trans-pinocarveol (about 1.20%), and limonene (1.0%) were the major components. The antimicrobial results showed that the oil inhibited nine bacteria and all the yeasts studied, and the activities were considerably dependent upon concentration and its bioactive compounds such as carvacrol, camphene, and limonene. Moreover, the essential oil of the gum was found to be more effective yeastcide than Nystatin, synthetic yeastcide. Furthermore, the antibacterial activities of the oil were lower than those of standard antibiotics, ampicillin sodium, and streptomycine sulfate under the conditions studied.

ANTIMICROBIAL ACTIVITY OF BURSERA MORELENSIS RAMÍREZ ESSENTIAL OIL

PubMed Central

M., Canales-Martinez; C.R., Rivera-Yañez; J., Salas-Oropeza; H.R., Lopez; M., Jimenez-Estrada; R., Rosas-Lopez; D.A., Duran; C., Flores; L.B., Hernandez; M.A., Rodriguez-Monroy

2017-01-01

Background: Bursera morelensis, known as “Aceitillo”, is an endemic tree of Mexico. Infusions made from the bark of this species have been used for the treatment of skin infections and for their wound healing properties. In this work, we present the results of a phytochemical and antimicrobial investigation of the essential oil of B. morelensis. Materials and Methods: The essential oil was obtained by a steam distillation method and analyzed using GC-MS. The antibacterial and antifungal activities were evaluated. Results: GC-MS of the essential oil demonstrated the presence of 28 compounds. The principal compound of the essential oil was a-Phellandrene (32.69%). The essential oil had antibacterial activity against Gram positive and negative strains. The most sensitive strains were S. pneumoniae, V. cholerae (cc) and E. coli (MIC 0.125 mg/mL, MBC 0.25 mg/mL). The essential oil was bactericidal for V. cholera (cc). The essential oil inhibited all the filamentous fungi. F. monilifome (IC50 = 2.27 mg/mL) was the most sensitive fungal strain. Conclusions: This work provides evidence that confirms the antimicrobial activity of the B. morelensis essential oil and this is a scientific support about of traditional uses of this species. PMID:28480418

Plant Antimicrobial Peptides as Potential Anticancer Agents

PubMed Central

Guzmán-Rodríguez, Jaquelina Julia; López-Gómez, Rodolfo

2015-01-01

Antimicrobial peptides (AMPs) are part of the innate immune defense mechanism of many organisms and are promising candidates to treat infections caused by pathogenic bacteria to animals and humans. AMPs also display anticancer activities because of their ability to inactivate a wide range of cancer cells. Cancer remains a cause of high morbidity and mortality worldwide. Therefore, the development of methods for its control is desirable. Attractive alternatives include plant AMP thionins, defensins, and cyclotides, which have anticancer activities. Here, we provide an overview of plant AMPs anticancer activities, with an emphasis on their mode of action, their selectivity, and their efficacy. PMID:25815333

Expanding the Bioactive Chemical Space of Anthrabenzoxocinones through Engineering the Highly Promiscuous Biosynthetic Modification Steps.

PubMed

Mei, Xianyi; Yan, Xiaoli; Zhang, Hui; Yu, Mingjia; Shen, Guangqing; Zhou, Linjun; Deng, Zixin; Lei, Chun; Qu, Xudong

2018-01-19

Anthrabenzoxocinones (ABXs) including (-)-ABXs and (+)-ABXs are a group of bacterial FabF-specific inhibitors with potent antimicrobial activity of resistant strains. Optimization of their chemical structures is a promising method to develop potent antibiotics. Through biosynthetic investigation, we herein identified and characterized two highly promiscuous enzymes involved in the (-)-ABX structural modification. The promiscuous halogenase and methyltransferase can respectively introduce halogen-modifications into various positions of the ABX scaffolds and methylation to highly diverse substrates. Manipulation of their activity in both of the (-)-ABXs and (+)-ABXs biosyntheses led to the generation of 14 novel ABX analogues of both enantiomers. Bioactivity assessment revealed that a few of the analogues showed significantly improved antimicrobial activity, with the C3-hydroxyl and chlorine substitutions critical for their activity. This study enormously expands the bioactive chemical space of the ABX family and FabF-specific inhibitors. The disclosed broad-selective biosynthetic machineries and structure-activity relationship provide a solid basis for further generation of potent antimicrobial agents.

From Synthesis to Biological Impact of Pd (II) Complexes: Synthesis, Characterization, and Antimicrobial and Scavenging Activity

PubMed Central

Sharma, Nitin Kumar; Ameta, Rakesh Kumar; Singh, Man

2016-01-01

The Pd (II) complexes with a series of halosubstituted benzylamine ligands (BLs) have been synthesized and characterized with different spectroscopic technique such as FTIR, UV/Vis, LCMS, 1H, and 13C NMR. Their molecular sustainability in different solvents such as DMSO, DMSO : H2O, and DMSO : PBS at physiological condition (pH 7.2) was determined by UV/Vis spectrophotometer. The in vitro antibacterial and antifungal activities of the complexes were investigated against Gram-positive and Gram-negative microbes and two different fungi indicated their significant biological potential. Additionally, their antioxidant activity has been analyzed with DPPH• free radical through spectrophotometric method and the result inferred them as an antioxidant. The stronger antibacterial and antioxidant activities of the synthesized complexes suggested them as a stronger antimicrobial agent. Our study advances the biological importance of palladium (II) amine complexes in the field of antimicrobial and antioxidant activities. PMID:27119023

Antimicrobial, antiviral and antioxidant activities of "água-mel" from Portugal.

PubMed

Miguel, Maria G; Faleiro, Leonor; Antunes, Maria D; Aazza, Smail; Duarte, Joana; Silvério, Ana R

2013-06-01

"Água-mel" is a honey-based product produced in Portugal for ancient times. Several attributes have been reported to "água-mel" particularly in the alleviation of simple symptoms of upper respiratory tract. Samples of "água-mel" from diverse beekeepers from different regions of Portugal were studied in what concerns antimicrobial, antioxidant and antiviral properties. The amounts of phenol and brown pigment were also evaluated and correlated with the antioxidant activities. A great variability on the levels of these compounds was found among samples which were responsible for the variability detected also on the antioxidant activities, independent on the method used. Generally, antioxidant activity correlated better with brown pigments' amount than with phenols' content. The antimicrobial activity found for "água-mel" samples confirm the virtues reported by popular findings. In addition, this work also reveals the antiviral properties of "água-mel" evidenced by a decrease on the infectivity of the Qβ bacteriophage. Copyright © 2013 Elsevier Ltd. All rights reserved.

Determination of the antimicrobial susceptibilities of Canadian isolates of Haemophilus influenzae, Streptococcus pneumoniae and Moraxella catarrhalis. Canadian Antimicrobial Study Group.

PubMed

Blondeau, J M; Suter, M; Borsos, S

1999-03-01

The susceptibility of Canadian isolates of three respiratory tract pathogens (Haemophilus influenzae, Moraxella catarrhalis and Streptococcus pneumoniae) to several antimicrobial agents were tested by two different methods. Beta-lactamase was produced by 68/211 (32.2%) of H. influenzae isolates and 64/75 (85.3%) of M. catarrhalis isolates. For S. pneumoniae, 19/156 (12.2%) isolates were resistant to penicillin (MIC > or = 0.12 mg/L) and two isolates had MICs of 1.5 mg/L. For some combinations of agents and organisms, different methods gave different values for the proportion of isolates susceptible. Regardless of methodology, for H. influenzae, the most active antimicrobials based on proportion of strains susceptible were ciprofloxacin (100%) and cefpodoxime (98.5-100%). For M. catarrhalis, the most active agents were azithromycin, cefaclor, cefixime, cefpodoxime, cefuroxime, ciprofloxacin, clarithromycin and loracarbef (100% each); the least active was ampicillin. Against penicillin-sensitive and -resistant pneumococci, the activity was not significantly different for azithromycin and clarithromycin (93.4-100%) and ciprofloxacin (MIC90 2.0 and 1.5 mg/L, respectively) but was different for cefuroxime (99.3% and 31.6%, respectively), cefaclor (MIC90 0.75 and > or = 256 mg/L, respectively), cefpodoxime (MIC90 0.047 and 1.5 mg/L, respectively) and loracarbef (MIC90 0.75 and > or = 256 mg/L, respectively). This study indicates the increasing incidence, in Canada, of beta-lactamase resistance in H. influenzae and M. catarrhalis and penicillin resistance in S. pneumoniae.

Antimicrobial activity of the imipenem/rifampicin combination against clinical isolates of Acinetobacter baumannii grown in planktonic and biofilm cultures.

PubMed

Wang, Yang; Bao, Wanguo; Guo, Na; Chen, Haiying; Cheng, Wei; Jin, Kunqi; Shen, Fengge; Xu, Jiancheng; Zhang, Qiaoli; Wang, Chao; An, Yanan; Zhang, Kaiyu; Wang, Feng; Yu, Lu

2014-12-01

To investigate the antimicrobial activity of imipenem and rifampicin alone and in combination against clinical isolates of Acinetobacter baumannii grown in planktonic and biofilm cultures. Minimum inhibitory concentrations were determined for each isolate grown in suspension and in biofilm using a microbroth dilution method. Chequerboard assays and the agar disk diffusion assay were used to determine synergistic, indifferent or antagonistic interactions between imipenem and rifampicin. We used the tissue culture plate method for A. baumannii biofilm formation to measure the percentage of biofilm inhibition and the amount of extracellular DNA after the treatment. To understand the synergistic mechanisms, we conducted hydroxyl radical formation assays. The results were verified by confocal laser scanning microscopy. Imipenem and rifampicin showed effective antimicrobial activity against suspensions and biofilm cultures of A. baumannii, respectively. Synergistic antimicrobial effects between imipenem and rifampicin were observed in 13 and 17 of the 20 clinical isolates when in suspension and in biofilms, respectively. Imipenem and rifampicin alone and in combination generated hydroxyl radicals, which are highly reactive oxygen forms and the major components of bactericidal agents. Furthermore, treatment with imipenem and rifampicin individually or in combination has obvious antibiofilm effects. The synergistic activity of imipenem and rifampicin against clinical isolates of A. baumannii (in suspension and in biofilms) was observed in vitro. Therefore, we conclude that imipenem combined with rifampicin has the potential to be used as a combinatorial therapy for the treatment of infectious diseases caused by A. baumannii.

Antimicrobial activities of pomelo (Citrus maxima) seed and pulp ethanolic extract

NASA Astrophysics Data System (ADS)

Sahlan, Muhamad; Damayanti, Vina; Tristantini, Dewi; Hermansyah, Heri; Wijanarko, Anondho; Olivia, Yuko

2018-02-01

Grapefruit (Citrus paradisi) seed extract is generally used as naturopathic medications, supplements, antiseptic and disinfecting agents and also as preservatives in food and cosmetics products. In vitro studies have demonstrated that grapefruit seed extract has anti bacterial properties against a range of gram-positive and gram-negative organisms. Indonesian grapefruit, known as pomelo (C. maxima), has similar characteristics, contents and is under the same genus (Citrus) as grapefruit; however it has not been completely utilized as a preservative. In this work we analyze the antimicrobial activities of ethanolic extract of Indonesian pomelo (C. maxima) seeds and pulp compared to the grapefruit (C. paradisi) seeds and pulp ethanolic extract. Ethanolic extracts of pomelo and grapefruit seeds and pulp are investigated for activities against Bacillus subtilis, Staphylococcus aureus, Escherichia coli and Candida albicans. The level of antimicrobial effects is established using agar diffusion method. Both of the ethanolic do not show any antimicrobial activities against C. albicans. The ethanolic extract of pomelo seeds and pulp used in this research give positive results with growth inhibition effect on B. subtilis, S. aureus and E. coli. The zones of inhibition ranges from 22 - 30 mm in diameter, which is higher to grapefruit seeds and pulp ethanolic extract (17 - 25 mm). Ethanolic extract of pomelo seeds and pulp has an antimicrobial effect, which makes it a natural preparation for use as an alternative preservative for food and cosmetic.

Antimicrobial activities of some Thai traditional medical longevity formulations from plants and antibacterial compounds from Ficus foveolata.

PubMed

Meerungrueang, W; Panichayupakaranant, P

2014-09-01

Medicinal plants involved in traditional Thai longevity formulations are potential sources of antimicrobial compounds. To evaluate the antimicrobial activities of some extracts from medicinal plants used in traditional Thai longevity formulations against some oral pathogens, including Streptococcus pyogenes, Streptococcus mitis, Streptococcus mutans, and Candida albicans. An extract that possessed the strongest antimicrobial activity was fractionated to isolate and identify the active compounds. Methanol and ethyl acetate extracts of 25 medicinal plants used as Thai longevity formulations were evaluated for their antimicrobial activity using disc diffusion (5 mg/disc) and broth microdilution (1.2-2500 µg/mL) methods. The ethyl acetate extract of Ficus foveolata Wall. (Moraceae) stems that exhibited the strongest antibacterial activity was fractionated to isolate the active compounds by an antibacterial assay-guided isolation process. The ethyl acetate extract of F. foveolata showed the strongest antibacterial activity with minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values of 19.5-39.0 and 39.0-156.2 µg/mL, respectively. On the basis of an antibacterial assay-guided isolation, seven antibacterial compounds, including 2,6-dimethoxy-1,4-benzoquinone (1), syringaldehyde (2), sinapaldehyde (3), coniferaldehyde (4), 3β-hydroxystigmast-5-en-7-one (5), umbelliferone (6), and scopoletin (7), were purified. Among these isolated compounds, 2,6-dimethoxy-1,4-benzoquinone (1) exhibited the strongest antibacterial activities against S. pyogenes, S. mitis, and S. mutans with MIC values of 7.8, 7.8, and 15.6 µg/mL, and MBC values of 7.8, 7.8, and 31.2 µg/mL, respectively. In addition, this is the first report of these antibacterial compounds in the stems of F. foveolata.

Antibacterial activity of jalapeño pepper (Capsicum annuum var. annuum) extract fractions against select foodborne pathogens.

PubMed

Bacon, Karleigh; Boyer, Renee; Denbow, Cynthia; O'Keefe, Sean; Neilson, Andrew; Williams, Robert

2017-05-01

Capsicum annuum fruits have been investigated for antimicrobial activity in a number of studies. Capsaicin or other cinnamic acid pathway intermediates are often suggested to be the antimicrobial component, however there are conflicting results. No research has specifically fractionated jalapeño pepper ( Capsicum annuum var. annuum ) extract to isolate and identify compound(s) responsible for inhibition. In this study, fractions were collected from jalapeño pepper extracts using reverse-phase HPLC and tested for antibacterial activity using the disk diffusion method. Following initial fractionation, two fractions (E and F) displayed antibacterial activity against all three pathogens ( p  >   .05). Commercial standards were screened to determine when they elude and it was found that capsaicin elutes at the same time as fraction E. Fractions E and F were subject to further HPLC fractionation and antibacterial analysis using two methods. The only fraction to display clear inhibition using both was fraction E1, inhibiting the growth of L. monocytogenes . Fraction E1 was analyzed using HPLC-MS. The resulting mass spectra revealed fraction E1 contained compounds belonging to a group of C. annuum -specific compounds known as capsianosides. Limited research is available on antibacterial activity of capsianosides, and a pure commercial standard is not available. In order to confirm the potential antimicrobial activity of the compound(s) isolated, methods need to be developed to isolate and purify capsianosides specifically from jalapeño peppers.

Antimicrobial activity of polyphenol-rich fractions from Sida alba L. (Malvaceae) against co-trimoxazol-resistant bacteria strains

PubMed Central

2012-01-01

Background The increased resistance of microorganisms to the currently used antimicrobials has lead to the evaluation of other agents that might have antimicrobial activity. Medicinal plants are sources of phytochemicals which are able to initiate different biological activities including antimicrobials Materials and methods In vitro antibacterial (MIC, MBC and time-kill studies) of polyphenol-rich fractions from Sida alba L. (Malvaceae) was assessed using ten bacteria strains (Gram-negative and Gram-positive). Results All test bacteria were susceptible to the polyphenol-rich fractions. Time-kill results showed that after 5 h exposition there was no viable microorganism in the initial inoculum and the effect of polyphenol-rich fractions was faster on Enterococcus faecalis (Gram-positive bacterium) comparatively to the other bacteria strains. Conclusion The data analysis indicates that the tested of polyphenol-rich fractions has significant effects when compared with the standard antibiotic. These results therefore justify the traditional use of sida alba L., alone or in combination with other herbs to treat bacterial infections. PMID:22364123

Antimicrobial activity and agricultural properties of bitter melon (Momordica charantia L.) grown in northern parts of Turkey: a case study for adaptation.

PubMed

Yaldız, Gülsüm; Sekeroglu, Nazım; Kulak, Muhittin; Demirkol, Gürkan

2015-01-01

This study was designed to determine the adaptation capability of bitter melon (Momordica charantia L.), which is widely grown in tropical and subtropical climates, in northern parts of Turkey. In this study, plant height, number of fruits, fruit length, fruit width, number of seeds and fruit weight of bitter melon grown in field conditions were determined. The antimicrobial effect of the ethanol extract of fruit and seeds against Pseudomonas aeruginosa, Escherichia coli, Staphylococcus aureus, Salmonella typhi, Aspergillus niger and Candida albicans microorganisms was tested in vitro by the disc diffusion method. In conclusion, plant height (260 cm), number of fruits (16 per  plant), number of seeds (30.2  per fruit), fruit width (3.8 cm), fruit length (10.6 cm) and fruit weight (117.28 g fruit(- 1)) were determined; fruits were found to have antimicrobial activity against A. niger; oil and seeds were found to have antimicrobial activity against A. niger and E. coli.

Evaluation of antimicrobial activity of silver nanoparticles for carboxymethylcellulose film applications in food packaging.

PubMed

Siqueira, Maria C; Coelho, Gustavo F; de Moura, Márcia R; Bresolin, Joana D; Hubinger, Silviane Z; Marconcini, José M; Mattoso, Luiz H C

2014-07-01

In this study, silver nanoparticles were prepared and incorporated into carboxymethylcellulose films to evaluate the antimicrobial activity for food packaging applications. The techniques carried out for material characterization were: infrared spectroscopy and thermal analysis for the silver nanoparticles and films, as well as particle size distribution for the nanoparticles and water vapor permeability for the films. The antimicrobial activity of silver nanoparticles prepared by casting method was investigated. The minimum inhibitory concentration (MIC) value of the silver nanoparticles to test Gram-positive (Enterococcus faecalis) and Gram-negative (Escherichia coli) microorganisms was carried out by the serial dilution technique, tested in triplicate to confirm the concentration used. The results were developed using the Mcfarland scale which indicates that the presence or absence of turbidity tube demonstrates the inhibition of bacteria in relation to the substance inoculated. It was found that the silver nanoparticles inhibited the growth of the tested microorganisms. The carboxymethylcellulose film embedded with silver nanoparticles showed the best antimicrobial effect against Gram-positive (E. faecalis) and Gram-negative (E. coli) bacteria (0.1 microg cm(-3)).

Structural characterization and antimicrobial properties of silver nanoparticles prepared by inverse microemulsion method.

PubMed

Wani, Irshad A; Khatoon, Sarvari; Ganguly, Aparna; Ahmed, Jahangeer; Ahmad, Tokeer; Manzoor, Nikhat

2013-01-01

Silver nanoparticles have been synthesized in the inverse microemulsions formed using three different surfactants viz., cetyl-trimethyl ammonium bromide (CTAB), Tergitol and Triton X-100. We have done a systematic study of the effect of the surfactants on the particle size and properties of the silver nanoparticles. Microscopic studies show the formation of spheres, cubes and discs shaped silver nanostructures with the size in the range from 8 to 40 nm. Surface plasmon resonance (SPR) peak was observed around 400 nm and 500 nm. In addition to SPR some extra peaks have also been observed due to the formation of silver metal clusters. The surface area increases from 3.45 to 15.06 m(2)/g with decreasing the size of silver nanoparticles (40-8 nm). To investigate the antimicrobial activity of silver nanoparticles, the nanoparticles were tested against the yeast, Candida albicans and the bacterium, E. coli. The results suggest very good antimicrobial activity of the silver nanoparticles against the test microbes. The mode of action of the antimicrobial activity was also proposed. Copyright © 2012 Elsevier B.V. All rights reserved.

Antimicrobial Efficacy of Octenidine Hydrochloride and Calcium Hydroxide with and Without a Carrier: A Broth Dilution Analysis

PubMed Central

Varghese, Vinaya Susan; Uppin, Veerendra; Bhat, Kishore; Pujar, Madhu; Hooli, Amruta B.; Kurian, Nirmal

2018-01-01

Background: An efficient antimicrobial agent action is required for a predetermined time period for absolute elimination of root canal microbes. Till date, there is limited or no data on the antimicrobial effect of octenidine as an intracanal medicament with chitosan (CTS) as a carrier against Candida albicans and Enterococcus faecalis. Aim: The aim of this microbiological study was to compare the antimicrobial efficacy of octenidine hydrochloride (OHC) and calcium hydroxide (Ca[OH]2) as intracanal medicaments, both independently and along with CTS as a carrier molecule against the common resistant endodontic pathogens. Materials and Methods: A total of 160 single-rooted anterior teeth were selected, root canal preparation was done, and teeth were divided into two groups and contaminated with C. albicans and E. faecalis, which were further divided into four test groups each according to intracanal medicaments used. CTS was used as a vehicle for OHC and Ca(OH)2 and antimicrobial assessment was performed on day 2 and day 7 following broth dilution method. Dentine samples were collected after each time interval, and the number of colony-forming units was determined. Results: All four medicaments used in this study showed antifungal and antibacterial activity that diminished from day 2 to day 7. Group I (OHC alone) and Group IV (Ca[OH]2 alone) showed significant antimicrobial activity against C. albicans and E. faecalis, respectively, than the other groups. Conclusion: A combination of OHC + CTS and Ca(OH)2+ CTS produced inferior results than that of the medicaments used alone. PMID:29599588

Antimicrobial efficacy of chlorhexidine digluconate alone and in combination with eucalyptus oil, tea tree oil and thymol against planktonic and biofilm cultures of Staphylococcus epidermidis.

PubMed

Karpanen, T J; Worthington, T; Hendry, E R; Conway, B R; Lambert, P A

2008-11-01

Effective skin antisepsis and disinfection of medical devices are key factors in preventing many healthcare-acquired infections associated with skin microorganisms, particularly Staphylococcus epidermidis. The aim of this study was to investigate the antimicrobial efficacy of chlorhexidine digluconate (CHG), a widely used antiseptic in clinical practice, alone and in combination with tea tree oil (TTO), eucalyptus oil (EO) and thymol against planktonic and biofilm cultures of S. epidermidis. Antimicrobial susceptibility assays against S. epidermidis in a suspension and in a biofilm mode of growth were performed with broth microdilution and ATP bioluminescence methods, respectively. Synergy of antimicrobial agents was evaluated with the chequerboard method. CHG exhibited antimicrobial activity against S. epidermidis in both suspension and biofilm (MIC 2-8 mg/L). Of the essential oils thymol exhibited the greatest antimicrobial efficacy (0.5-4 g/L) against S. epidermidis in suspension and biofilm followed by TTO (2-16 g/L) and EO (4-64 g/L). MICs of CHG and EO were reduced against S. epidermidis biofilm when in combination (MIC of 8 reduced to 0.25-1 mg/L and MIC of 32-64 reduced to 4 g/L for CHG and EO, respectively). Furthermore, the combination of EO with CHG demonstrated synergistic activity against S. epidermidis biofilm with a fractional inhibitory concentration index of <0.5. The results from this study suggest that there may be a role for essential oils, in particular EO, for improved skin antisepsis when combined with CHG.

The Effects of Allium sativum Extracts on Biofilm Formation and Activities of Six Pathogenic Bacteria

PubMed Central

Mohsenipour, Zeinab; Hassanshahian, Mehdi

2015-01-01

Background: Garlic is considered a rich source of many compounds, which shows antimicrobial effects. The ability of microorganisms to adhere to both biotic and abiotic surfaces and to form biofilm is responsible for a number of diseases of chronic nature, demonstrating extremely high resistance to antibiotics. Bacterial biofilms are complex communities of sessile microorganisms, embedded in an extracellular matrix and irreversibly attached to various surfaces. Objectives: The present study evaluated the antimicrobial activity of Allium sativum extract against the biofilms of six pathogenic bacteria and their free-living forms. The clinical isolates in this study had not been studied in any other studies, especially in regard to biofilm disruption and inhibition of biofilm cell metabolic activity. Materials and Methods: Antimicrobial activities of A. sativum L. extracts (methanol and ethanol extracts) against planktonic forms of bacteria were determined using the disc diffusion method. The minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) values were evaluated by a macrobroth dilution technique. The anti-biofilm effects were assessed by microtiter plate method. Results: The results showed that the A. sativum L. extract discs did not have any zone of inhibition for the tested bacteria. However, The MIC values of A. sativum L. extracts (0.078 - 2.5 mg/mL) confirmed the high ability of these extracts for inhibition of planktonic bacteria. A. sativum L. extracts were efficient to inhibit biofilm structures and the concentration of each extract had a direct relation with the inhibitory effect. Conclusions: Finally, it can be suggested that the extracts of this plant be applied as antimicrobial agents against these pathogens, particularly in biofilm forms. PMID:26464762

Evaluation of wound healing, antioxidant and antimicrobial efficacy of Jasminum auriculatum Vahl. leaves.

PubMed

Arun, Mittal; Satish, Sardana; Anima, Pandey

2016-01-01

To validate the ethno-therapeutic claim of the traditionally used plant Jasminum auriculatum (J. auriculatum) in skin diseases, by evaluating its wound healing potential along with its antioxidant and antimicrobial properties; so as to understand their role in wound healing. Excision and incision wound models were used to evaluate the wound healing activity on albino rats. The wound healing potential was assessed by measuring rate of wound contraction, epithelialization period, hydroxyproline content, skin breaking strength and histopathological parameters. Reference standard drug was Nitrofurazone ointment. The antioxidant activity was determined using 2, 2-diphenyl-1-picrylhydrazyl (DPPH) method. The antimicrobial activity was determined by agar well diffusion method and minimum inhibitory concentration by serial dilution method. Higher rate of wound contraction (83.66±0.50% on 15th day), decrease in the period of epithelialization (17.83±1.6days), higher skin breaking strength (170.71±1.52g), higher collagen content and favourable histopathological changes revealed that topical application of ointment containing successive ethanolic extract (S.E.E) of J. auriculatum leaves has the most potent wound healing ability compared to control group in both the models studied. The DPPH radical scavenging activity of successive ethanolic extract was found to be 33.39µg/ml. Successive ethanolic extract was found to be most effective against Pseudomonas auregenosa having a zone of inhibition 16.65±0.6mm and the minimum inhibitory concentration was 0.78mg/ml. The data of this study indicate that successive ethanolic extract of the leaves exhibit potent wound healing, antioxidant and antimicrobial properties. This justifies the ethno-medicinal use of plant for the treatment of wound and microbial infections.

Synthesis and biological evaluation of pyrazolylthiazole carboxylic acids as potent anti-inflammatory-antimicrobial agents.

PubMed

Khloya, Poonam; Kumar, Satish; Kaushik, Pawan; Surain, Parveen; Kaushik, Dhirender; Sharma, Pawan K

2015-03-15

Current Letter presents design, synthesis and biological evaluation of a novel series of pyrazolylthiazole carboxylates 1a-1p and corresponding acid derivatives 2a-2p. All 32 novel compounds were tested for their in vivo anti-inflammatory activity by carrageenan-induced rat paw edema method as well as for in vitro antimicrobial activity. All the tested compounds exhibited excellent AI activity profile. Three compounds 1p (R=Cl, R(1)=Cl), 2c (R=H, R(1)=F) and 2n (R=Cl, R(1)=OCH3) were identified as potent anti-inflammatory agents exhibiting edema inhibition of 93.06-89.59% which is comparable to the reference drug indomethacin (91.32%) after 3h of carrageenan injection while most of the other compounds displayed inhibition ⩾80%. In addition, pyrazolylthiazole carboxylic acids (2a-2p) also showed good antimicrobial profile. Compound 2h (R=OCH3, R(1)=Cl) showed excellent antimicrobial activity (MIC 6.25μg/mL) against both Gram positive bacteria comparable with the reference drug ciprofloxacin (MIC 6.25μg/mL). Copyright © 2015 Elsevier Ltd. All rights reserved.

Purification, characterization and application of a novel antimicrobial peptide from Andrias davidianus blood.

PubMed

Pei, J; Feng, Z; Ren, T; Sun, H; Han, H; Jin, W; Dang, J; Tao, Y

2018-01-01

The Andrias davidianus has been known as a traditional Chinese medicine for a long time. Its blood is considered as a waste or by-product of the meat production industry. Although there are reports on isolation of the antimicrobial peptides from different resources, there are no reports of their isolation from A. davidianus blood. In this work, an antimicrobial peptide, andricin B, was isolated from the blood of A. davidianus by an innovative method in which the magnetic liposome adsorption was combined with reversed-phase high-performance liquid chromatography. The structure, antimicrobial activity and safety of andricin B were further investigated. Amino acid sequence was determined by N-terminal sequencing and found to be Gly-Leu-Thr-Arg-Leu-Phe-Ser-Val-Ile-Lys. Circular dichroism (CD) spectra and prediction of three-dimensional structure by bioinformatics software suggested the presence of a well-defined random coil conformation. Andricin B was found to be active against all bacteria tested in this study as well as some fungi. The minimum inhibitory concentrations (MICs) were in the range 8-64 μg ml -1 . Moreover, the haemolytic testing also suggested that andricin B could be considered safe at the MICs. Finally, andricin B was shown to inhibit the growth of Staphylococcus aureus in the cooked meat of A. davidianus. This study shows that andricin B is a promising novel antimicrobial peptide that may provide further insights towards the development of new drugs. This is the pioneer study on screening and isolation of antimicrobial peptide from the blood of Andrias davidianus. Here, we have developed a novel method by combining magnetic liposomes adsorption with reversed-phase high-performance liquid chromatography to purify and screen the antimicrobial peptides. From this screen, we identified a novel antimicrobial peptide which we name as andricin B. Andricin B is unique as it checks the growth of both Gram-positive and Gram-negative bacteria as well as few fungal species. © 2017 The Society for Applied Microbiology.

Diagnostic Accuracy Assessment of Sensititre and Agar Disk Diffusion for Determining Antimicrobial Resistance Profiles of Bovine Clinical Mastitis Pathogens▿

PubMed Central

Saini, V.; Riekerink, R. G. M. Olde; McClure, J. T.; Barkema, H. W.

2011-01-01

Determining the accuracy and precision of a measuring instrument is pertinent in antimicrobial susceptibility testing. This study was conducted to predict the diagnostic accuracy of the Sensititre MIC mastitis panel (Sensititre) and agar disk diffusion (ADD) method with reference to the manual broth microdilution test method for antimicrobial resistance profiling of Escherichia coli (n = 156), Staphylococcus aureus (n = 154), streptococcal (n = 116), and enterococcal (n = 31) bovine clinical mastitis isolates. The activities of ampicillin, ceftiofur, cephalothin, erythromycin, oxacillin, penicillin, the penicillin-novobiocin combination, pirlimycin, and tetracycline were tested against the isolates. Diagnostic accuracy was determined by estimating the area under the receiver operating characteristic curve; intertest essential and categorical agreements were determined as well. Sensititre and the ADD method demonstrated moderate to highly accurate (71 to 99%) and moderate to perfect (71 to 100%) predictive accuracies for 74 and 76% of the isolate-antimicrobial MIC combinations, respectively. However, the diagnostic accuracy was low for S. aureus-ceftiofur/oxacillin combinations and other streptococcus-ampicillin combinations by either testing method. Essential agreement between Sensititre automatic MIC readings and MIC readings obtained by the broth microdilution test method was 87%. Essential agreement between Sensititre automatic and manual MIC reading methods was 97%. Furthermore, the ADD test method and Sensititre MIC method exhibited 92 and 91% categorical agreement (sensitive, intermediate, resistant) of results, respectively, compared with the reference method. However, both methods demonstrated lower agreement for E. coli-ampicillin/cephalothin combinations than for Gram-positive isolates. In conclusion, the Sensititre and ADD methods had moderate to high diagnostic accuracy and very good essential and categorical agreement for most udder pathogen-antimicrobial combinations and can be readily employed in veterinary diagnostic laboratories. PMID:21270215

Effects of allspice, cinnamon, and clove bud essential oils in edible apple films on physical properties and antimicrobial activities.

PubMed

Du, W-X; Olsen, C W; Avena-Bustillos, R J; McHugh, T H; Levin, C E; Friedman, Mendel

2009-09-01

Essential oils (EOs) derived from plants are rich sources of volatile terpenoids and phenolic compounds. Such compounds have the potential to inactivate pathogenic bacteria on contact and in the vapor phase. Edible films made from fruits or vegetables containing EOs can be used commercially to protect food against contamination by pathogenic bacteria. EOs from cinnamon, allspice, and clove bud plants are compatible with the sensory characteristics of apple-based edible films. These films could extend product shelf life and reduce risk of pathogen growth on food surfaces. This study evaluated physical properties (water vapor permeability, color, tensile properties) and antimicrobial activities against Escherichia coli O157:H7, Salmonella enterica, and Listeria monocytogenes of allspice, cinnamon, and clove bud oils in apple puree film-forming solutions formulated into edible films at 0.5% to 3% (w/w) concentrations. Antimicrobial activities were determined by 2 independent methods: overlay of the film on top of the bacteria and vapor phase diffusion of the antimicrobial from the film to the bacteria. The antimicrobial activities against the 3 pathogens were in the following order: cinnamon oil > clove bud oil > allspice oil. The antimicrobial films were more effective against L. monocytogenes than against the S. enterica. The oils reduced the viscosity of the apple solutions and increased elongation and darkened the colors of the films. They did not affect water vapor permeability. The results show that apple-based films with allspice, cinnamon, or clove bud oils were active against 3 foodborne pathogens by both direct contact with the bacteria and indirectly by vapors emanating from the films.

Effects of Coal Fly Ash Particulate Matter on the Antimicrobial Activity of Airway Surface Liquid

PubMed Central

Vargas Buonfiglio, Luis G.; Mudunkotuwa, Imali A.; Abou Alaiwa, Mahmoud H.; Vanegas Calderón, Oriana G.; Borcherding, Jennifer A.; Gerke, Alicia K.; Zabner, Joseph; Grassian, Vicki H.

2017-01-01

Background: Sustained exposure to ambient particulate matter (PM) is a global cause of mortality. Coal fly ash (CFA) is a byproduct of coal combustion and is a source of anthropogenic PM with worldwide health relevance. The airway epithelia are lined with fluid called airway surface liquid (ASL), which contains antimicrobial proteins and peptides (AMPs). Cationic AMPs bind negatively charged bacteria to exert their antimicrobial activity. PM arriving in the airways could potentially interact with AMPs in the ASL to affect their antimicrobial activity. Objectives: We hypothesized that PM can interact with ASL AMPs to impair their antimicrobial activity. Methods: We exposed pig and human airway explants, pig and human ASL, and the human cationic AMPs β-defensin-3, LL-37, and lysozyme to CFA or control. Thereafter, we assessed the antimicrobial activity of exposed airway samples using both bioluminescence and standard colony-forming unit assays. We investigated PM-AMP electrostatic interaction by attenuated total reflection Fourier-transform infrared spectroscopy and measuring the zeta potential. We also studied the adsorption of AMPs on PM. Results: We found increased bacterial survival in CFA-exposed airway explants, ASL, and AMPs. In addition, we report that PM with a negative surface charge can adsorb cationic AMPs and form negative particle–protein complexes. Conclusion: We propose that when CFA arrives at the airway, it rapidly adsorbs AMPs and creates negative complexes, thereby decreasing the functional amount of AMPs capable of killing pathogens. These results provide a novel translational insight into an early mechanism for how ambient PM increases the susceptibility of the airways to bacterial infection. https://doi.org/10.1289/EHP876 PMID:28696208

Antioxidant, Antimicrobial and Antiproliferative Activities of Five Lichen Species

PubMed Central

Mitrović, Tatjana; Stamenković, Slaviša; Cvetković, Vladimir; Tošić, Svetlana; Stanković, Milan; Radojević, Ivana; Stefanović, Olgica; Čomić, Ljiljana; Đačić, Dragana; Ćurčić, Milena; Marković, Snežana

2011-01-01

The antioxidative, antimicrobial and antiproliferative potentials of the methanol extracts of the lichen species Parmelia sulcata, Flavoparmelia caperata, Evernia prunastri, Hypogymnia physodes and Cladonia foliacea were evaluated. The total phenolic content of the tested extracts varied from 78.12 to 141.59 mg of gallic acid equivalent (GA)/g of extract and the total flavonoid content from 20.14 to 44.43 mg of rutin equivalent (Ru)/g of extract. The antioxidant capacities of the lichen extracts were determined by 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals scavenging. Hypogymnia physodes with the highest phenolic content showed the strongest DPPH radical scavenging effect. Further, the antimicrobial potential of the lichen extracts was determined by a microdilution method on 29 microorganisms, including 15 strains of bacteria, 10 species of filamentous fungi and 4 yeast species. A high antimicrobial activity of all the tested extracts was observed with more potent inhibitory effects on the growth of Gram (+) bacteria. The highest antimicrobial activity among lichens was demonstrated by Hypogymnia physodes and Cladonia foliacea. Finally, the antiproliferative activity of the lichen extracts was explored on the colon cancer adenocarcinoma cell line HCT-116 by MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) viability assay and acridine orange/ethidium bromide staining. The methanol extracts of Hypogymnia physodes and Cladonia foliacea showed a better cytotoxic activity than the other extracts. All lichen species showed the ability to induce apoptosis of HCT-116 cells. PMID:21954369

Non-thermal plasma technology for the development of antimicrobial surfaces: a review

NASA Astrophysics Data System (ADS)

Nikiforov, Anton; Deng, Xiaolong; Xiong, Qing; Cvelbar, U.; DeGeyter, N.; Morent, R.; Leys, Christophe

2016-05-01

Antimicrobial coatings are in high demand in many fields including the biomaterials and healthcare sectors. Within recent progress in nanoscience and engineering at the nanoscale, preparation of nanocomposite films containing metal nanoparticles (such as silver nanoparticles, copper nanoparticles, zinc oxide nanoparticles) is becoming an important step in manufacturing biomaterials with high antimicrobial activity. Controlled release of antibiotic agents and eliminating free nanoparticles are of equal importance for engineering antimicrobial nanocomposite materials. Compared to traditional chemical ‘wet’ methods, plasma deposition and plasma polymerization are promising approaches for the fabrication of nanocomposite films with the advantages of gas phase dry processes, effective use of chemicals and applicability to various substrates. In this article, we present a short overview of state-of-the-art engineering of antimicrobial materials based on the use of non-thermal plasmas at low and atmospheric pressure.

CS-AMPPred: An Updated SVM Model for Antimicrobial Activity Prediction in Cysteine-Stabilized Peptides

PubMed Central

Porto, William F.; Pires, Állan S.; Franco, Octavio L.

2012-01-01

The antimicrobial peptides (AMP) have been proposed as an alternative to control resistant pathogens. However, due to multifunctional properties of several AMP classes, until now there has been no way to perform efficient AMP identification, except through in vitro and in vivo tests. Nevertheless, an indication of activity can be provided by prediction methods. In order to contribute to the AMP prediction field, the CS-AMPPred (Cysteine-Stabilized Antimicrobial Peptides Predictor) is presented here, consisting of an updated version of the Support Vector Machine (SVM) model for antimicrobial activity prediction in cysteine-stabilized peptides. The CS-AMPPred is based on five sequence descriptors: indexes of (i) α-helix and (ii) loop formation; and averages of (iii) net charge, (iv) hydrophobicity and (v) flexibility. CS-AMPPred was based on 310 cysteine-stabilized AMPs and 310 sequences extracted from PDB. The polynomial kernel achieves the best accuracy on 5-fold cross validation (85.81%), while the radial and linear kernels achieve 84.19%. Testing in a blind data set, the polynomial and radial kernels achieve an accuracy of 90.00%, while the linear model achieves 89.33%. The three models reach higher accuracies than previously described methods. A standalone version of CS-AMPPred is available for download at and runs on any Linux machine. PMID:23240023

Magnetically Recoverable and Reusable Antimicrobial Nanocomposite Based on Activated Carbon, Magnetite Nanoparticles, and Silver Nanoparticles for Water Disinfection

DOE PAGES

Furlan, Ping; Fisher, Adam; Furlan, Alexander; ...

2017-06-06

Recent advancements in nanotechnology have led to the development of innovative, low-cost and highly efficient water disinfection technologies that may replace or enhance the conventional methods. In this study, we introduce a novel procedure for preparing a bifunctional activated carbon nanocomposite in which nanoscale-sized magnetic magnetite and antimicrobial silver nanoparticles are incorporated (MACAg). The antimicrobial efficacy of the nanocomposite was tested against Escherichia coli (E. coli). MACAg (0.5 g, 0.04% Ag) was found to remove and kill 10 6–10 7 CFU (colony-forming units) in 30 min via a shaking test and the removing and killing rate of the nanocomposites increasedmore » with increasing silver content and decreased with increasing CFU. The inhibition zone tests revealed, among the relevant components, only Ag nanoparticles and Ag + ions showed antimicrobial activities. The MACAg was easily recoverable from treated water due to its magnetic properties and was able to remove and kill 10 6 CFU after multiple-repeated use. The MACAg nanocomposite also demonstrated its feasibility and applicability for treating a surface water containing 10 5 CFU. Combining low cost due to easy synthesis, recoverability, and reusability with high antimicrobial efficiency, MACAg may provide a promising water disinfection technology that will find wide applications.« less

Antimicrobial Impacts of Essential Oils on Food Borne-Pathogens.

PubMed

Ozogul, Yesim; Kuley, Esmeray; Ucar, Yilmaz; Ozogul, Fatih

2015-01-01

The antimicrobial activity of twelve essential oil (pine oil, eucalyptus, thyme, sage tea, lavender, orange, laurel, lemon, myrtle, lemon, rosemary and juniper) was tested by a disc diffusion method against food borne pathogens (Escherichia coli, Salmonella paratyphi A, Klebsiella pneumoniae, Yersinia enterocolitica, Pseudomonas aeruginosa, Aeromonas hydrophila, Campylobacter jejuni, Enterococcus faecalis, Staphylococcus aureus). The major components in essential oils were monoterpenes hydrocarbons, α-pinene, limonene; monoterpene phenol, carvacrol and oxygenated monoterpenes, camphor, 1,8-cineole, eucalyptol, linalool and linalyl acetate. Although the antimicrobial effect of essential oils varied depending on the chemical composition of the essential oils and specific microorganism tested, majority of the oils exhibited antibacterial activity against one or more strains. The essential oil with the lowest inhibition zones was juniper with the values varied from 1.5 to 6 mm. However, the components of essential oil of thyme and pine oil are highly active against food borne pathogen, generating the largest inhibition zones for both gram negative and positive bacteria (5.25-28.25 mm vs. 12.5-30 mm inhibition zones). These results indicate the possible use of the essential oils on food system as antimicrobial agents against food-borne pathogen. The article also offers some promising patents on applications of essential oils on food industry as antimicrobial agent.

Antimicrobial Peptides: Insights into Membrane Permeabilization, Lipopolysaccharide Fragmentation and Application in Plant Disease Control.

PubMed

Datta, Aritreyee; Ghosh, Anirban; Airoldi, Cristina; Sperandeo, Paola; Mroue, Kamal H; Jiménez-Barbero, Jesús; Kundu, Pallob; Ramamoorthy, Ayyalusamy; Bhunia, Anirban

2015-07-06

The recent increase in multidrug resistance against bacterial infections has become a major concern to human health and global food security. Synthetic antimicrobial peptides (AMPs) have recently received substantial attention as potential alternatives to conventional antibiotics because of their potent broad-spectrum antimicrobial activity. These peptides have also been implicated in plant disease control for replacing conventional treatment methods that are polluting and hazardous to the environment and to human health. Here, we report de novo design and antimicrobial studies of VG16, a 16-residue active fragment of Dengue virus fusion peptide. Our results reveal that VG16KRKP, a non-toxic and non-hemolytic analogue of VG16, shows significant antimicrobial activity against Gram-negative E. coli and plant pathogens X. oryzae and X. campestris, as well as against human fungal pathogens C. albicans and C. grubii. VG16KRKP is also capable of inhibiting bacterial disease progression in plants. The solution-NMR structure of VG16KRKP in lipopolysaccharide features a folded conformation with a centrally located turn-type structure stabilized by aromatic-aromatic packing interactions with extended N- and C-termini. The de novo design of VG16KRKP provides valuable insights into the development of more potent antibacterial and antiendotoxic peptides for the treatment of human and plant infections.

Magnetically Recoverable and Reusable Antimicrobial Nanocomposite Based on Activated Carbon, Magnetite Nanoparticles, and Silver Nanoparticles for Water Disinfection

DOE Office of Scientific and Technical Information (OSTI.GOV)

Furlan, Ping; Fisher, Adam; Furlan, Alexander

Recent advancements in nanotechnology have led to the development of innovative, low-cost and highly efficient water disinfection technologies that may replace or enhance the conventional methods. In this study, we introduce a novel procedure for preparing a bifunctional activated carbon nanocomposite in which nanoscale-sized magnetic magnetite and antimicrobial silver nanoparticles are incorporated (MACAg). The antimicrobial efficacy of the nanocomposite was tested against Escherichia coli (E. coli). MACAg (0.5 g, 0.04% Ag) was found to remove and kill 10 6–10 7 CFU (colony-forming units) in 30 min via a shaking test and the removing and killing rate of the nanocomposites increasedmore » with increasing silver content and decreased with increasing CFU. The inhibition zone tests revealed, among the relevant components, only Ag nanoparticles and Ag + ions showed antimicrobial activities. The MACAg was easily recoverable from treated water due to its magnetic properties and was able to remove and kill 10 6 CFU after multiple-repeated use. The MACAg nanocomposite also demonstrated its feasibility and applicability for treating a surface water containing 10 5 CFU. Combining low cost due to easy synthesis, recoverability, and reusability with high antimicrobial efficiency, MACAg may provide a promising water disinfection technology that will find wide applications.« less

Comparative evaluation of the antimicrobial activity of natural extracts of Morinda citrifolia, papain and aloe vera (all in gel formulation), 2% chlorhexidine gel and calcium hydroxide, against Enterococcus faecalis: An in vitro study

PubMed Central

Bhardwaj, Anuj; Ballal, Suma; Velmurugan, Natanasabapathy

2012-01-01

Aim: A comparative evaluation of the antimicrobial activity of natural extracts of Morinda citrifolia, papain, and aloe vera (all in gel formulations), 2% chlorhexidine gel and calcium hydroxide, against Enterococcus faecalis—an in vitro study. Materials and Methods: The antimicrobial efficacy was assessed in vitro using dentin shavings collected at 2 depths of 200 and 400 μm. The total colony forming units at the end of 1, 3, and 5 days were assessed. Results: The overall percentage inhibition of bacterial growth (200 and 400 μm depth) was 100% with chlorhexidine gel. This was followed by M. citrifolia gel (86.02%), which showed better antimicrobial efficacy as compared with aloe vera gel (78.9%), papain gel (67.3%), and calcium hydroxide (64.3%). There was no statistical difference between data at 200 and 400 μm depth. Conclusion: Chlorhexidine gel showed the maximum antimicrobial activity against E. faecalis, whereas calcium hydroxide showed the least. Among the natural intracanal medicaments, M. citrifolia gel consistently exhibited good inhibition up to the 5th day followed by aloe vera gel and papain gel. PMID:22876022

Antimicrobial Testing Methods & Procedures: MB-03-07

EPA Pesticide Factsheets

This protocol describes the procedures for the preparation of carriers for the following methods: the AOAC UDM, AOAC Tuberculocidal Activity of Disinfectants Test, AOAC GSPT, the Disinfectant Towelette Test, and the AOAC SAT.

Covalent Dimer Species of β-Defensin Defr1 Display Potent Antimicrobial Activity against Multidrug-Resistant Bacterial Pathogens▿

PubMed Central

Taylor, Karen; McCullough, Bryan; Clarke, David J.; Langley, Ross J.; Pechenick, Tali; Hill, Adrian; Campopiano, Dominic J.; Barran, Perdita E.; Dorin, Julia R.; Govan, John R. W.

2007-01-01

Beta defensins comprise a family of cationic, cysteine-rich antimicrobial peptides, predominantly expressed at epithelial surfaces. Previously we identified a unique five-cysteine defensin-related peptide (Defr1) that, when synthesized, is a mixture of dimeric isoforms and exhibits potent antimicrobial activity against Escherichia coli and Pseudomonas aeruginosa. Here we report that Defr1 displays antimicrobial activity against an extended panel of multidrug-resistant nosocomial pathogens for which antimicrobial treatment is limited or nonexistent. Defr1 fractions were collected by high-pressure liquid chromatography and analyzed by gel electrophoresis and mass spectrometry. Antimicrobial activity was initially investigated with the type strain Pseudomonas aeruginosa PAO1. All fractions tested displayed equivalent, potent antimicrobial activity levels comparable with that of the unfractionated Defr1. However, use of an oxidized, monomeric six-cysteine analogue (Defr1 Y5C), or of reduced Defr1, gave diminished antimicrobial activity. These results suggest that the covalent dimer structure of Defr1 is crucial to antimicrobial activity; this hypothesis was confirmed by investigation of a synthetic one-cysteine variant (Defr1-1cys). This gave an activity profile similar to that of synthetic Defr1 but only in an oxidized, dimeric form. Thus, we have shown that covalent, dimeric molecules based on the Defr1 β-defensin sequence demonstrate antimicrobial activity even in the absence of the canonical cysteine motif. PMID:17353239

In vivo antimicrobial activity of silver nanoparticles produced via a green chemistry synthesis using Acacia rigidula as a reducing and capping agent

PubMed Central

Escárcega-González, Carlos Enrique; Garza-Cervantes, JA; Vázquez-Rodríguez, A; Montelongo-Peralta, Liliana Zulem; Treviño-González, MT; Díaz Barriga Castro, E; Saucedo-Salazar, EM; Chávez Morales, RM; Regalado Soto, DI; Treviño González, FM; Carrazco Rosales, JL; Cruz, Rocío Villalobos; Morones-Ramírez, José Rubén

2018-01-01

Introduction One of the main issues in the medical field and clinical practice is the development of novel and effective treatments against infections caused by antibiotic-resistant bacteria. One avenue that has been approached to develop effective antimicrobials is the use of silver nanoparticles (Ag-NPs), since they have been found to exhibit an efficient and wide spectrum of antimicrobial properties. Among the main drawbacks of using Ag-NPs are their potential cytotoxicity against eukaryotic cells and the latent environmental toxicity of their synthesis methods. Therefore, diverse green synthesis methods, which involve the use of environmentally friendly plant extracts as reductive and capping agents, have become attractive to synthesize Ag-NPs that exhibit antimicrobial effects against resistant bacteria at concentrations below toxicity thresholds for eukaryotic cells. Purpose In this study, we report a green one-pot synthesis method that uses Acacia rigidula extract as a reducing and capping agent, to produce Ag-NPs with applications as therapeutic agents to treat infections in vivo. Materials and methods The Ag-NPs were characterized using transmission electron microscopy (TEM), high-resolution TEM, selected area electron diffraction, energy-dispersive spectroscopy, ultraviolet–visible, and Fourier transform infrared. Results We show that Ag-NPs are spherical with a narrow size distribution. The Ag-NPs show antimicrobial activities in vitro against Gram-negative (Escherichia coli, Pseudomonas aeruginosa, and a clinical multidrug-resistant strain of P. aeruginosa) and Gram-positive (Bacillus subtilis) bacteria. Moreover, antimicrobial effects of the Ag-NPs, against a resistant P. aeruginosa clinical strain, were tested in a murine skin infection model. The results demonstrate that the Ag-NPs reported in this work are capable of eradicating pathogenic resistant bacteria in an infection in vivo. In addition, skin, liver, and kidney damage profiles were monitored in the murine infection model, and the results demonstrate that Ag-NPs can be used safely as therapeutic agents in animal models. Conclusion Together, these results suggest the potential use of Ag-NPs, synthesized by green chemistry methods, as therapeutic agents against infections caused by resistant and nonresistant strains. PMID:29713166

Structural, textural and morphological characteristics of tannins from Acacia mearnsii encapsulated using sol-gel methods: Applications as antimicrobial agents.

PubMed

Dos Santos, Cristiane; Vargas, Álvaro; Fronza, Ney; Dos Santos, João Henrique Zimnoch

2017-03-01

Tannins from Acacia mearnsii were encapsulated using four different sol-gel methods acid (SGAR), basic (SGBR), silicate (SGSR) and non-hydrolytic (SGNHR) routes. The hybrid materials were analyzed using a set of techniques to characterize their structure, texture and morphology. The antimicrobial performance of the encapsulated materials was evaluated against different microorganisms (Staphylococcus aureus, Escherichia coli, Aspergillus niger and Candida sp.). The data showed that the encapsulation route significantly affects the characteristics of the resulting hybrid materials. Better functional performances were obtained using the silicate route, which produced mesoporous materials with a small surface area (0.96m 2 g -1 ) and small particle size (<1nm). These characteristics promoted the gradual release of tannins in an aqueous medium and improved their interactions with microorganisms. Furthermore, the process demonstrated the preservation of tannins after synthesis and increased antimicrobial activity (via a controlled tannin release), as demonstrated by the moderate activity against filamentous fungi and yeast. Copyright © 2016. Published by Elsevier B.V.

Antioxidant and antimicrobial activities of ethyl acetate extract, fractions and compounds from stem bark of Albizia adianthifolia (Mimosoideae).

PubMed

Tamokou, Jean de Dieu; Simo Mpetga, Deke James; Keilah Lunga, Paul; Tene, Mathieu; Tane, Pierre; Kuiate, Jules Roger

2012-07-18

Albizia adianthifolia is used traditionally in Cameroon to treat several ailments, including infectious and associated diseases. This work was therefore designed to investigate the antioxidant and antimicrobial activities of ethyl acetate extract, fractions and compounds isolated from the stem bark of this plant. The plant extract was prepared by maceration in ethyl acetate. Its fractionation was done by column chromatography and the structures of isolated compounds were elucidated using spectroscopic data in conjunction with literature data. The 1,1-diphenyl-2-picrylhydrazyl (DPPH) and trolox equivalent antioxidant capacity (TEAC) assays were used to detect the antioxidant activity. Broth micro-dilution method was used for antimicrobial test. Total phenol content was determined spectrophotometrically in the extracts by using Folin-Ciocalteu method. The fractionation of the extract afforded two known compounds: lupeol (1) and aurantiamide acetate (2) together with two mixtures of fatty acids: oleic acid and n-hexadecanoic acid (B₁); n-hexadecanoic acid, octadecanoic acid and docosanoic acid (B₂). Aurantiamide acetate was the most active compound. The total phenol concentration expressed as gallic acid equivalents (GAE) was found to vary from 1.50 to 13.49 μg/ml in the extracts. The antioxidant activities were well correlated with the total phenol content (R² = 0.946 for the TEAC method and R² = 0.980 for the DPPH free-radical scavenging assay). Our results clearly reveal that the ethyl acetate extract from the stem bark of A. adianthifolia possesses antioxidant and antimicrobial principles. The antioxidant activity of this extract as well as that of compound 2 are being reported herein for the first time. These results provide promising baseline information for the potential use of this plant as well as compound 2 in the treatment of oxidative damage and infections associated with the studied microorganisms.

Rationally designed dual functional block copolymers for bottlebrush-like coatings: In vitro and in vivo antimicrobial, antibiofilm, and antifouling properties.

PubMed

Gao, Qiang; Yu, Meng; Su, Yajuan; Xie, Meihua; Zhao, Xin; Li, Peng; Ma, Peter X

2017-03-15

Numerous antimicrobial coatings have been developed for biomedical devices/implants, but few can simultaneously fulfill the requirements for antimicrobial and antifouling ability and biocompatibility. In this study, to develop an antimicrobial and antibiofilm surface coating, diblock amphiphilic molecules with antimicrobial and antifouling segments in a single chain were rationally designed and synthesized. Cationic antimicrobial polypeptides (AMP) were first synthesized by N-carboxyanhydride ring-opening polymerization (NCA-ROP). Heterofunctionalized poly(ethylene glycol) with different lengths (methacrylate-PEG n -tosyl, n=10/45/90) was synthesized and site-specifically conjugated with polypeptides to form diblock amphiphiles. Along with increased PEG chain length, hemolytic activity was considerably improved, and broad-spectrum antimicrobial activity is retained. Three MA-PEG n -b-AMP copolymers were further grafted onto the surface of silicone rubber (a commonly used catheter material) via plasma/UV-induced surface polymerizations to form a bottlebrush-like coating with excellent antimicrobial activity against several pathogenic bacteria (Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus), and effectively prevent biofilm formation. This bottlebrush coating also greatly reduced protein adsorption and platelet adhesion, indicating its excellent antifouling ability. An in vitro cytotoxicity study also demonstrated that this coating is biocompatible with mammalian cells. After subcutaneous implantation of the materials in rats, we demonstrated that the g-PEG 45 -b-AMP bottlebrush coating exhibits significant anti-infective activity in vivo. Thus, this facilely synthesized PEGylated AMP bottlebrush coating is a feasible method to prevent biomedical devices-associated infections. Current antimicrobial coatings are often associated with concerns such as antibiotic resistance, environmental pollution, short-time antimicrobial activity, biofouling, poor blood compatibility and cytotoxicity, etc. To overcome these drawbacks, a robust PEGylated cationic amphiphilic peptides-based bottlebrush-like surface coating is demonstrated here, which fulfil the requirements of antimicrobial and antifouling as well as biocompatibility in the meantime. Briefly, the rational designed g-PEG n -b-AMP block copolymers (n=10/45/90) were synthesized and grafted on silicone surface. This bottlebrush-like coating efficiently kill the contacted bacteria and prevent the biofilm formation, greatly reduced protein and platelet adhesion. It also exhibits excellent blood compatibility and low cytotoxicity in vitro. In particular, g-PEG 45 -b-AMP coating exhibits significant anti-infection effect in vivo. This coating offering an effective strategy for combating biomedical devices-associated infections. Copyright © 2017 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Antibacterial activity against Clostridium genus and antiradical activity of the essential oils from different origin.

PubMed

Kačániová, Miroslava; Vukovič, Nenad; Horská, Elena; Salamon, Ivan; Bobková, Alica; Hleba, Lukáš; Fiskelová, Martina; Vatľák, Alexander; Petrová, Jana; Bobko, Marek

2014-01-01

In the present study, the antimicrobial and antiradical activities of 15 essential oils were investigated. The antimicrobial activities were determined by using agar disc diffusion and broth microdilution methods against Clostridium genus and antioxidant properties of essential oils by testing their scavenging effect on DPPH radicals activities. We determined the antibacterial activity of Clostridium butyricum, Clostridium hystoliticum, Clostridium intestinale, Clostridium perfringens and Clostridium ramosum. We obtained the original commercial essential oils samples of Lavandula angustifolia, Carum carvi, Pinus montana, Mentha piperita, Foeniculum vulgare Mill., Pinus sylvestris, Satureia montana, Origanum vulgare L. (2 samples), Pimpinella anisum, Rosmarinus officinalis L., Salvia officinalis L., Abies alba Mill., Chamomilla recutita L. Rausch and Thymus vulgaris L. produced in Slovakia (Calendula a.s., Nova Lubovna, Slovakia). The results of the disk diffusion method showed very high essential oils activity against all tested strains of microorganisms. The best antimicrobial activity against C. butyricum was found at Pimpinella anisum, against C. hystoliticum was found at Pinus sylvestris, against C. intestinale was found at Satureia hortensis L., against C. perfringens was found at Origanum vulgare L. and against C. ramosum was found at Pinus sylvestris. The results of broth microdilution assay showed that none of the essential oils was active against C. hystoliticum. The best antimicrobial activity against C. butyricum was found at Abies alba Mill., against C. intestinale was found at Abies alba Mill., against C. perfringens was found at Satureia montana and against C. ramosum was found at Abius alba and Carum carvi. Antioxidant DPPH radical scavenging activity was determined at several solutions of oil samples (50 μL.mL(-1)-0.39 μL.mL(-1)) and the best scavenging effect for the highest concentration (50 μL.mL(-1)) was observed. The antioxidant properties were different in particular plant species. The highest% of inhibition after 30 min. of reaction was observed at Origanum vulgare (93%), Satureia montana (90.66%) and Lavandula augustifolia (90.22%).

Identification of Phenolic Compounds and Evaluation of Antioxidant and Antimicrobial Properties of Euphorbia Tirucalli L.

PubMed Central

de Araújo, Keline Medeiros; de Lima, Alessandro; Silva, Jurandy do N.; Rodrigues, Larissa L.; Amorim, Adriany G. N.; Quelemes, Patrick V.; dos Santos, Raimunda C.; Rocha, Jefferson A.; de Andrades, Éryka O.; Leite, José Roberto S. A.; Mancini-Filho, Jorge; da Trindade, Reginaldo Almeida

2014-01-01

Bioactive compounds extracted from natural sources can benefit human health. The aim of this work was to determine total phenolic content and antioxidant activity in extracts of Euphorbia tirucalli L. followed by identification and quantification of the phenolic compounds, as well as their antibacterial activities. Antioxidant activities were determined by DPPH and ABTS•+ assay. Identification of phenolic compounds was performed using high-performance liquid chromatography (HPLC), and antimicrobial activities were verified by agar dilution methods and MIC values. Total phenolic content ranged from 7.73 to 30.54 mg/100 g gallic acid equivalent. Extracts from dry plants showed higher antioxidant activities than those from fresh ones. The DPPH EC50 values were approximately 12.15 μg/mL and 16.59 μg/mL, respectively. Antioxidant activity measured by the ABTS method yielded values higher than 718.99 μM trolox/g for dry plants, while by the Rancimat® system yielded protection factors exceeding 1 for all extracts, comparable to synthetic BHT. Ferulic acid was the principal phenolic compound identified and quantified through HPLC-UV in all extracts. The extracts proved effective inhibitory potential for Staphylococcus epidermidis and Staphylococcus aureus. These results showed that extracts of Euphorbia tirucalli L. have excellent antioxidant capacity and moderate antimicrobial activity. These can be attributed to the high concentration of ferulic acid. PMID:26784670

Antimicrobial activity of the diterpenes flexibilide and sinulariolide derived from Sinularia flexibilis Quoy and Gaimard 1833 (Coelenterata: Alcyonacea, Octocorallia).

PubMed

Aceret, T L; Coll, J C; Uchio, Y; Sammarco, P W

1998-07-01

The soft coral Sinularia flexibilis is rarely overgrown by bacteria and algae. Various studies have shown that it contains diterpenes that protect it from competitors and predators. However, of the many diterpenoids isolated from S. flexibilis, only sinulariolide has been studied for antibiotic properties. Samples of soft corals were collected from Orpheus Island and freeze-dried for chemical extraction and isolation of pure diterpenes. Antimicrobial activity of the diterpenes was determined using the disc assay method with antibiotics as controls and the minimum inhibitory concentrations of the diterpenes were determined using the Tube Dilution Technique. Two out of the five diterpenes tested (sinulariolide and flexibilide), showed marked antimicrobial activity and inhibited growth of Gram-positive bacteria. Flexibilide was effective even at concentrations as low as 5 ppm, whereas sinulariolide was effective at concentrations of 10 ppm. These compounds show potential as antibiotics.

Biosynthesis of silver nanoparticles using Ocimum sanctum (Tulsi) leaf extract and screening its antimicrobial activity

NASA Astrophysics Data System (ADS)

Singhal, Garima; Bhavesh, Riju; Kasariya, Kunal; Sharma, Ashish Ranjan; Singh, Rajendra Pal

2011-07-01

Development of green nanotechnology is generating interest of researchers toward ecofriendly biosynthesis of nanoparticles. In this study, biosynthesis of stable silver nanoparticles was done using Tulsi ( Ocimum sanctum) leaf extract. These biosynthesized nanoparticles were characterized with the help of UV-vis spectrophotometer, Atomic Absorption Spectroscopy (AAS), Dynamic light scattering (DLS), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and Transmission electron microscopy (TEM). Stability of bioreduced silver nanoparticles was analyzed using UV-vis absorption spectra, and their antimicrobial activity was screened against both gram-negative and gram-positive microorganisms. It was observed that O. sanctum leaf extract can reduce silver ions into silver nanoparticles within 8 min of reaction time. Thus, this method can be used for rapid and ecofriendly biosynthesis of stable silver nanoparticles of size range 4-30 nm possessing antimicrobial activity suggesting their possible application in medical industry.

Antitumour and antimicrobial activities of endophytic streptomycetes from pharmaceutical plants in rainforest.

PubMed

Li, J; Zhao, G-Z; Chen, H-H; Wang, H-B; Qin, S; Zhu, W-Y; Xu, L-H; Jiang, C-L; Li, W-J

2008-12-01

The aim of this study was to screen antitumour and antimicrobial activities of endophytic actinomycetes isolated from pharmaceutical plants in rainforest in Yunnan province, China. Antitumour activity was studied by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and antimicrobial activity was determined by agar well diffusion method. The high bioactive endophytic isolates were identified and further investigated for the presence of polyketide synthases (PKS-I, PKS-II) and nonribosomal peptide synthetases (NRPS) sequences by specific amplification. The molecular identification confirmed that the 41 isolates showed significant activities were members of the genus Streptomyces. Among them, 31.7% of endophytic streptomycete cultures were cytotoxic against A549 cells, 29.3% against HL-60 cells, 85.4% against BEL-7404 cells, 90.2% against P388D1 cells, 65.9% were active against Escherichia coli, 24.4% against Staphylococcus aureus, 31.7% against Staphylococcus epidermidis, 12.2% against Candida albicans and no strain displayed antagonistic activity against Klebsiella pneumoniae. High frequencies of positive PCR amplification were obtained for PKS-I (34.1%), PKS-II (63.4%) and NRPS (61.0%) biosynthetic systems. Many endophytic streptomycetes isolated from pharmaceutical plants in rainforest possess remarkable and diverse antitumour and antimicrobial bioactivities. These endophytic streptomycetes are precious resources obtained from rainforests, and they could be a promising source for bioactive agents.

Inhibition of growth of highly resistant bacterial and fungal pathogens by a natural product.

PubMed

Hafidh, Rand R; Abdulamir, Ahmed S; Vern, Law Se; Abu Bakar, Fatimah; Abas, Faridah; Jahanshiri, Fatemeh; Sekawi, Zamberi

2011-01-01

The continuous escalation of resistant bacteria against a wide range of antibiotics necessitates discovering novel unconventional sources of antibiotics. B. oleracea L (red cabbage) is health-promoting food with proven anticancer and anti-inflammatory activities. However, it has not been researched adequately for its antimicrobial activity on potential resistant pathogens. The methanol crude extract of B. oleracea L. was investigated for a possible anti-microbial activity. The screening method was conducted using disc diffusion assay against 22 pathogenic bacteria and fungi. It was followed by evaluation of the minimum inhibitory concentration (MIC). Moreover, the antibacterial and the antifungal activities were confirmed using the minimum bactericidal concentration (MBC) and the minimum fungicidal concentration (MFC), respectively. Remarkable, antibacterial activity was evident particularly against highly infectious microorganisms such as Methicillin-resistant Staphylococcus aureus, Escherichia coli O157:H7, Pseudomonas aeruginosa, Klebsiella pneumoniae, Staphylococcus aureus, and Salmonella enterica serovar Typhimurium as well as against human fungal pathogens, Trichophyton rubrum and Aspergillus terreus. Red cabbage is a rich source of phenolic compounds, anthocyanins being the most abundant class, which might explain its potent antimicrobial action. This extract is potentially novel for future antimicrobials, inexpensive, and readily available at a large scale for pharmaceutical companies for further investigation and processing.

Inhibition of Growth of Highly Resistant Bacterial and Fungal Pathogens by a Natural Product

PubMed Central

Hafidh, Rand R; Abdulamir, Ahmed S; Vern, Law Se; Abu Bakar, Fatimah; Abas, Faridah; Jahanshiri, Fatemeh; Sekawi, Zamberi

2011-01-01

The continuous escalation of resistant bacteria against a wide range of antibiotics necessitates discovering novel unconventional sources of antibiotics. B. oleracea L (red cabbage) is health-promoting food with proven anticancer and anti-inflammatory activities. However, it has not been researched adequately for its antimicrobial activity on potential resistant pathogens. The methanol crude extract of B. oleracea L. was investigated for a possible anti-microbial activity. The screening method was conducted using disc diffusion assay against 22 pathogenic bacteria and fungi. It was followed by evaluation of the minimum inhibitory concentration (MIC). Moreover, the antibacterial and the antifungal activities were confirmed using the minimum bactericidal concentration (MBC) and the minimum fungicidal concentration (MFC), respectively. Remarkable, antibacterial activity was evident particularly against highly infectious microorganisms such as Methicillin-resistant Staphylococcus aureus, Escherichia coli O157:H7, Pseudomonas aeruginosa, Klebsiella pneumoniae, Staphylococcus aureus, and Salmonella enterica serovar Typhimurium as well as against human fungal pathogens, Trichophyton rubrum and Aspergillus terreus. Red cabbage is a rich source of phenolic compounds, anthocyanins being the most abundant class, which might explain its potent antimicrobial action. This extract is potentially novel for future antimicrobials, inexpensive, and readily available at a large scale for pharmaceutical companies for further investigation and processing. PMID:21915230

Antimicrobial activity of Lactobacillus strains of chicken origin against bacterial pathogenss.

PubMed

Dec, Marta; Puchalski, Andrzej; Nowaczek, Anna; Wernicki, Andrzej

2016-03-01

This study was conducted to identify and evaluate the antimicrobial activity of some Lactobacillus isolates of chicken origin. Among 90 isolates 14 Lactobacillus species were distinguished using MALDI-TOF mass spectrometry and 16S-ARDRA. The dominant species was L. salivarius (34.4%), followed by L. johnsonii (23.3%), L. crispatus (13.3%) and L. reuteri (11.1%). All lactobacilli were screened for antimicrobial activity against wild-type strains of Salmonella enterica, Escherichia coli, and Clostridium perfringens. Results from the agar slab method showed that all Lactobacillus isolates were able to produce active compounds on solid media with antagonistic properties against these pathogens. The highest sensitivity to lactobacilli was observed in C. perfringens strains, and the lowest in E. coli. Lactobacillus salivarius exhibited particularly strong antagonism towards all of the indicator bacteria. Strains of L. ingluviei and L. johnsonii and one strain of L. salivarius (10d) selectively inhibited the growth of C. perfringens. No antimicrobial activity of many Lactobacillus isolates was observed when cell-free culture supernatant was used in a well diffusion assay. All Lactobacillus isolates exhibited the ability to produce H2O2 and proved to be hydrophobic (excluding one of L. salivarius). [Int Microbiol 19(1):57-67 (2016)]. Copyright© by the Spanish Society for Microbiology and Institute for Catalan Studies.

Antityrosinase and antimicrobial activities from Thai medicinal plants.

PubMed

Dej-Adisai, Sukanya; Meechai, Imron; Puripattanavong, Jindaporn; Kummee, Sopa

2014-04-01

Various dermatological disorders and microbial skin infection can cause hyperpigmentation. Therefore, screenings for whitening and antimicrobial agents from Thai medicinal plants have been of research interest. Seventy-seven ethanol plant extracts were investigated for antityrosinase activity, eleven samples showed the tyrosinase inhibition more than 50 % were further preliminary screening for antimicrobial activity by agar disc diffusion and broth micro-dilution methods. Artocarpus integer (Thunb.) Merr. (Moraceae) root extract, which showed the potential of tyrosinase inhibition with 90.57 ± 2.93 % and antimicrobial activity against Staphylococcus aureus, S. epidermidis, Propionibacterium acnes and Trichophyton mentagophytes with inhibition zone as 9.10 ± 0.00, 10.67 ± 0.09, 15.25 ± 0.05 and 6.60 ± 0.17 mm, respectively was selected for phytochemical investigation. Three pure compounds were isolated as artocarpin, cudraflavone C and artocarpanone. And artocarpanone exhibited anti-tyrosinase effect; artocarpin and cudraflavone C also showed the potential of antibacterial activity against S. aureus, S. epidermidis and P. acnes with MIC at 2, 4 and 2 μg/ml, respectively and MBC at 32 μg/ml for these bacteria. So, these pure compounds are interesting for further study in order to provide possibilities of new whitening and antibacterial development. This will be the first report of phytochemical investigation of A. integer root.

Antioxidant and antimicrobial potentials of Serbian red wines produced from international Vitis vinifera grape varieties.

PubMed

Radovanović, Aleksandra N; Jovančićević, Branimir S; Radovanović, Blaga C; Mihajilov-Krstev, Tatjana; Zvezdanović, Jelena B

2012-08-15

Antioxidant and antimicrobial potentials of Serbian red wines produced from different international Vitis vinifera grape varieties and their correlation with contents of phenolic compounds were studied by spectrophotometric and chromatographic methods. The antioxidant activity of red wines was estimated through their ability to scavenge 2,2'-diphenyl-1-picrylhydrazyl free radical (DPPH(•) ). The red wines, gallic acid, (+)-catechin and quercetin were screened in vitro for antimicrobial activity against Gram-positive and Gram-negative strains using microdilution and disc diffusion techniques. Excellent correlations between the contents of quercetin-3-glucoside (R(2) = 0.9463) and quercetin (R(2) = 0.9337) and DPPH(•) -scavenging ability of the red wines were found. Serbian red wines exhibited significant activity against Staphylococcus aureus, Listeria inocua, Micrococcus flavus, Sarcina lutea, Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa, Salmonella enteritidis and Shigella sonnei strains, which was in correlation with their phenolic composition and antioxidant activity. The compounds gallic acid, quercetin and (+)-catechin showed high activity against B. subtilis, S. aureus, S. lutea and M. flavus Gram-positive and S. enteritidis and P. aeruginosa Gram-negative strains. The results show that quercetin-3-glucoside and quercetin concentrations can be used as markers for the determination of antioxidant and antimicrobial potentials of red wines. Copyright © 2012 Society of Chemical Industry.

Chemical Composition, Antimicrobial and Antioxidant Activities of Essential Oils from Two Avicennia schaueriana Stapf & Leechm. Ex Moldenke (Acanthaceae) Populations

PubMed Central

Machado, Kamilla N.; Kaneko, Telma M.; Young, Maria Cláudia M.; Murakami, Cynthia; Cordeiro, Inês; Moreno, Paulo Roberto H.

2017-01-01

Background: Avicennia schaueriana Stapf & Leechm. ex Moldenke (Acanthaceae) is a native species from the Brazilian mangroves presenting ecological and economic significance. This study compared the composition and the biological activities from the essential oils obtained from two A. schaueriana populations collected at Jureia-Itatins and Ilha do Cardoso. Methods: Essential oils were obtained by conventional means, and their compositions were analyzed by GC-MS. Screening assays for antimicrobial activity were carried out by the microdilution method and the antioxidant potential was assessed by the DPPH scavenging method. Results: The GC-MS analysis indicated that the Jureia oil (1) was composed mostly of the fatty acids palmitic (46.5%) and myristic (11.6%) acids, while the main components for the Ilha do Cardoso oil (2) were eugenol (19.7%), eugenol acetate (12.9%) and palmitic acid (15.1%). The oils showed an IC50 of 0.9 ± 0.011 mg/mL for 1 and 1.13 ± 0.028 mg/mL for 2 in the DPPH assay. The antimicrobial assay indicated MIC > 217 µg/mL for all tested microorganisms. Conclusions: The different essential oil composition may indicate the presence of chemotypes for A. schaueriana. The antioxidant activity of the oils was weak if compared with flavonoids. Despite the high MIC values, these oils presented some antibacterial potential against Pseudomonas aeruginosa. PMID:28930241

A New Method of Producing a Natural Antibacterial Peptide by Encapsulated Probiotics Internalized with Inulin Nanoparticles as Prebiotics.

PubMed

Cui, Lian-Hua; Yan, Chang-Guo; Li, Hui-Shan; Kim, Whee-Soo; Hong, Liang; Kang, Sang-Kee; Choi, Yun-Jaie; Cho, Chong-Su

2018-04-28

Synbiotics are a combination of probiotics and prebiotics, which lead to synergistic benefits in host welfare. Probiotics have been used as an alternative to antibiotics. Among the probiotics, Pediococcus acidilactici (PA) has shown excellent antimicrobial activity against Salmonella Gallinarum (SG) as a major poultry pathogen and has improved the production performances of animals. Inulin is widely used as a prebiotic for the improvement of animal health and growth. The main aim of this study is to investigate the effect of the antimicrobial activity of inulin nanoparticles (INs)-internalized PA encapsulated into alginate/chitosan/alginate (ACA) microcapsules (MCs) in future in vivo application. The prepared phthalyl INs (PINs) were characterized by DLS and FE-SEM. The contents of phthal groups in phthalyl inulin were estimated by ¹H-NMR measurement as 25.1 mol.-%. The sizes of the PINs measured by DLS were approximately 203 nm. Internalization into PA was confirmed by confocal microscopy and flow cytometry. Antimicrobial activity of PIN-internalized probiotics encapsulated into ACA MCs was measured by co-culture antimicrobial assays on SG. PIN-internalized probiotics had a higher antimicrobial ability than that of ACA MCs loaded with PA/inulin or PA. Interestingly, when PINs were treated with PA and encapsulated into ACA MCs, as a natural antimicrobial peptide, pediocin was produced much more in the culture medium compared with other groups inulin-loaded ACA MCs and PA-encapsulated into ACA MCs.

Phyto-mediated metallic nano-architectures via Melissa officinalis L.: synthesis, characterization and biological properties.

PubMed

Fierascu, Irina; Georgiev, Milen I; Ortan, Alina; Fierascu, Radu Claudiu; Avramescu, Sorin Marius; Ionescu, Daniela; Sutan, Anca; Brinzan, Alexandru; Ditu, Lia Mara

2017-09-29

The development of methods for obtaining new materials with antimicrobial properties, based on green chemistry principles has been a target of research over the past few years. The present paper describes the phyto-mediated synthesis of metallic nano-architectures (gold and silver) via an ethanolic extract of Melissa officinalis L. (obtained by accelerated solvent extraction). Different analytic methods were applied for the evaluation of the extract composition, as well as for the characterization of the phyto-synthesized materials. The cytogenotoxicity of the synthesized materials was evaluated by Allium cepa assay, while the antimicrobial activity was examined by applying both qualitative and quantitative methods. The results demonstrate the synthesis of silver nanoparticles (average diameter 13 nm) and gold nanoparticles (diameter of ca. 10 nm); the bi-metallic nanoparticles proved to have a core-shell flower-like structure, composed of smaller particles (ca. 8 nm). The Ag nanoparticles were found not active on nuclear DNA damage. The Au nanoparticles appeared nucleoprotective, but were aggressive in generating clastogenic aberrations in A. cepa root meristematic cells. Results of the antimicrobial assays show that silver nanoparticles were active against most of the tested strains, as the lowest MIC value being obtained against B. cereus (approx. 0.0015 mM).

Influence of CuO nanoparticle on palm oil based alkyd resin preparation and its antimicrobial activity

NASA Astrophysics Data System (ADS)

Ruey Ong, Huei; Maksudur Rahman Khan, Md.; Ramli, Ridzuan; Shein Hong, Chi; Yunus, Rosli Mohd

2018-03-01

An alkyd resin has been synthesized from palm oil that reacted with glycerol and phthalic anhydride by alcoholysis-polyesterification process and co-catalyzed by CuO nanoparticle. The CuO nanoparticle was pre-prepared in the glycerol via sol gel method, which creates a new reaction condition for resin preparation. The resins were characterized by fourier transform infrared spectroscopy (FTIR), where a new ester linkage bond (C-O-C) was noticed for resin sample. The antimicrobial activity and the curing behaviour of the resin were determined by Kirby-Bauer and differential scanning calorimeter technique. It was found that, the addition of CuO speeded up the reaction rate and played antimicrobial role. Moreover, it shortens the reaction time of alcoholysis and polyesterification process.

In Vitro Evaluation of Antimicrobial Activity of Alimentary Canal Extracts from the Red Palm Weevil, Rhynchophorus ferrugineus Olivier Larvae.

PubMed

Sewify, Gamal H; Hamada, Hanan M; Alhadrami, Hani A

2017-01-01

The invasive red palm weevil, Rhynchophorus ferrugineus Olivier (Coleoptera: Curculionidae), is considered one of the world's most devastating insect pests to palm trees. It was observed that larvae of this pest are able to inhibit microbial growth on the rearing media when they start feeding and this observation has led us to study the effect of red palm weevils on various microbial species. The antimicrobial effect of extracts from different parts of the alimentary canal on Gram positive bacteria ( Enterococcus faecalis and Staphylococcus aureus ), Gram negative bacteria ( Escherichia coli and Klebsiella spp.), Candida albicans, and Penicillium sp. was tested using the agar well diffusion method. All extracts inhibited the tested microbial species. Foregut extracts had the greatest zones of growth inhibition. Enterococcus faecalis , Staphylococcus aureus, and Penicillium sp. were significantly sensitive to the extracts and had the largest growth inhibition zones. It is concluded that the gut extracts contain potent antimicrobial activity and may provide a new source of antimicrobial peptides.

Particulate Respirators Functionalized with Silver Nanoparticles Showed Excellent Real-Time Antimicrobial Effects against Pathogens.

PubMed

Zheng, Clark Renjun; Li, Shuai; Ye, Chengsong; Li, Xinyang; Zhang, Chiqian; Yu, Xin

2016-07-05

Particulate respirators designed to filtrate fine particulate matters usually do not possess antimicrobial functions. The current study aimed to functionalize particulate respirators with silver nanoparticles (nanosilver or AgNPs), which have excellent antimicrobial activities, utilizing a straightforward and effective method. We first enhanced the nanosilver-coating ability of nonwoven fabrics from a particulate respirator through surface modification by sodium oleate. The surfactant treatment significantly improved the fabrics' water wet preference where the static water contact angles reduced from 122° to 56°. Both macroscopic agar-plate tests and microscopic scanning electron microscope (SEM) characterization revealed that nanosilver functionalized fabrics could effectively inhibit the growth of two model bacterial strains (i.e., Staphylococcus aureus and Pseudomonas aeruginosa). The coating of silver nanoparticles would not affect the main function of particulate respirators (i.e., filtration of fine air-borne particles). Nanosilver coated particulate respirators with excellent antimicrobial activities can provide real-time protection to people in regions with severe air pollution against air-borne pathogens.

Synthesis and characterization of silver-copper core-shell nanoparticles using polyol method for antimicrobial agent

NASA Astrophysics Data System (ADS)

Hikmah, N.; Idrus, N. F.; Jai, J.; Hadi, A.

2016-06-01

Silver and copper nanoparticles are well-known as the good antimicrobial agent. The nano-size of particles influences in enhancing the antimicrobial activity. This paper discusses the effect of molarity on the microstructure and morphology of silver-copper core-shell nanoparticles prepared by a polyol method. In this study, silver-copper nanoparticles are synthesized through the green approach of polyol method using ethylene glycol (EG) as green solvent and reductant, and polyoxyethylene-(80)-sorbitan monooleate (Tween 80) as a nontoxic stabilizer. The phase and morphology of silver-copper nanoparticles are characterized by X-ray diffraction (XRD) and Field emission scanning electron microscope (FESEM) and Transmission electron microscope (TEM). The results XRD confirm the pure crystalline of silver and copper nanoparticles with face-centered cubic (FCC) structure. FESEM and TEM analysis confirm the existence of Ag and Cu nanoparticles in core-shell shape.

Synthesis and Pharmacological Evaluation of Some New Pyrimidine Derivatives Containing 1,2,4-Triazole

PubMed Central

Khanage, Shantaram Gajanan; Raju, S. Appala; Mohite, Popat Baban; Pandhare, Ramdas Bhanudas

2012-01-01

Purpose: An efficient method has been described for synthesis of 6-(substituted aryl)-4-(3,5-diphenyl-1H-1,2,4-triazol-1-yl)-1, 6-dihydropyrimidine-2-thiol, as a beneficial antimicrobial, anticonvulsant and anticancer agents. Methods: The clalcones of title compounds were synthesized in three steps and subsequently these chalcones were further reacted with thiourea in the presence of KOH in ethanol, which led to the formation of dihydropyrimidine derivatives (4a-j). Compounds 4a-j were screened for their in vitro antimicrobial activity by agar well method and their anticonvulsant activity by the MES model. Anticancer activity of two newly synthesized heterocycles were evaluated at National Cancer Institute (NCI) Maryland, USA against 60 cell lines of different human tumor at a single dose of 10-5 M. Results: Compound 4b, 4c, 4d, 4i and 4j were exhibited significant antimicrobial potential against tested strains at 50μg/ml and 100μg/ml concentrations. Out of the ten compounds studied 4a, 4b, 4c, 4h and 4j showed comparable MES activity to Phenytoin and Carbamazepine after 0.5h. Tested compounds did not showed to be more potent than standard drugs after 4h. Compound 4a and 4d were found active on Non-Small Cell Lung Cancer (HOP-92). Conclusion: Ten noveldihydropyrimidine analogues has been synthesized, characterized and found to bepromising antibacterial, anticonvulsant and antitumor agents. PMID:24312796

Studies of the in vitro anticancer, antimicrobial and antioxidant potentials of selected Yemeni medicinal plants from the island Soqotra

PubMed Central

2009-01-01

Background Recent years have witnessed that there is a revival of interest in drug discovery from medicinal plants for the maintenance of health in all parts of the world. The aim of this work was to investigate 26 plants belonging to 17 families collected from a unique place in Yemen (Soqotra Island) for their in vitro anticancer, antimicrobial and antioxidant activities. Methods The 26 plants were extracted with methanol and hot water to yield 52 extracts. Evaluation for in vitro anticancer activity was done against three human cancer cell lines (A-427, 5637 and MCF-7) by using an established microtiter plate assay based on cellular staining with crystal violet. Antimicrobial activity was tested against three Gram-positive bacteria, two Gram-negative bacteria, one yeast species and three multiresistant Staphylococcus strains by using an agar diffusion method and the determination of MIC against three Gram-positive bacteria with the broth micro-dilution assay. Antioxidant activity was investigated by measuring the scavenging activity of the DPPH radical. Moreover, a phytochemical screening of the methanolic extracts was done. Results Notable cancer cell growth inhibition was observed for extracts from Ballochia atro-virgata, Eureiandra balfourii and Hypoestes pubescens, with IC50 values ranging between 0.8 and 8.2 μg/ml. The methanol extracts of Acanthospermum hispidum, Boswellia dioscorides, Boswellia socotrana, Commiphora ornifolia and Euphorbia socotrana also showed noticeable antiproliferative potency with IC50 values < 50 μg/ml. The greatest antimicrobial activity was exhibited by extracts from Acacia pennivenia, Boswellia dioscorides, Boswellia socotrana, Commiphora ornifolia, Euclea divinorum, Euphorbia socotrana, Leucas samhaensis, Leucas virgata, Rhus thyrsiflora, and Teucrium sokotranum with inhibition zones > 15 mm and MIC values ≤ 250 μg/ml. In addition, the methanolic extracts of Acacia pennivenia, Boswellia dioscorides, Boswellia socotrana and Commiphora ornifolia showed good antioxidant potential at low concentrations (more than 80% at 50 μg/ml). Conclusion Our results show once again that medicinal plants can be promising sources of natural products with potential anticancer, antimicrobial and antioxidative activity. The results will guide the selection of some plant species for further pharmacological and phytochemical investigations. PMID:19320966

Screening of the constituents, antimicrobial and antioxidant activity of endemic Origanum hypericifolium O. Schwartz & P.H. Davis.

PubMed

Celik, Ali; Nur Herken, E; Arslan, Idris; Zafer Ozel, M; Mercan, Nazime

2010-10-01

The chemical compositions, total phenol content, antioxidant and antimicrobial activities with oxidant status of the essential oil from an endemic Turkish species, Origanum hypericifolium, were investigated. Steam distillation (SD) was used to isolate the essential oils, and the chemical analyses were performed by gas chromatography-mass spectrometry (GC-MS). The antimicrobial activity was tested by agar disc diffusion method against Morganella morganii (clinic isolate), Micrococcus flavus (clinic isolate), Micrococcus luteus NRLL B-4375, Proteus vulgaris RSKK 96026, Escherichia coli ATCC 11230, Escherichia coli ATCC 25922, Yersinia enterecolitica RSKK 1501, Staphylococcus aureus ATCC 25923, S. aureus ATCC 25933, S. aureus ATCC 12598, S. aureus (clinic isolate), MRSA 1 (clinic isolate), MRSA 2 (clinic isolate), MRSA 3 (clinic isolate) and MRSA 4 (clinic isolate). The major compounds found in volatiles of O. hypericifolium were p-cymene, carvacrol and γ-terpinene. Results showed that O. hypericifolium has the potential for being used in food and medicine because of its antioxidant and antibacterial activity.

Composition and antimicrobial activity of the essential oil from the branches of Jacaranda cuspidifolia Mart. growing in Sichuan, China.

PubMed

Yuan, Juanjuan; Gan, Tian; Liu, Yingtian; Gao, Hui; Xu, Weifeng; Zhang, Tao; Tan, Rui; Cai, Zhenghong; Jiang, Hezhong

2018-06-01

This study represents the first report on the chemical composition and antimicrobial activity of the essential oil from the branches of Jacaranda cuspidifolia Mart. Thirty-three compounds were identified by Gas Chromatography-Mass Spectrometry (GC-MS) and the major constituents of the essential oil were Palmitic acid (31.36%), (Z) - 9,17-Octadecadienal (12.06%), Ethyl palmitate (3.81%), Perhydrofarnesyl acetone (2.07%), γ-Maaliene (1.88%), and Cedro (1.42%) and 9,12-Octadecadienoic acid ethyl ester (1.42%). The in vitro antimicrobial activities of the essential oil were evaluated by the disc diffusion method, and the inhibition zones against Escherichia coli, Staphylococcus aureus and Candida albicans were 7.10, 8.20 and 7.25 mm, respectively. The oil showed moderate activities against E. coli, S. aureus and C. albicans with minimum inhibition concentration (MIC) values of 17.3 mg/mL, 12.9 mg/mL and 16.0 mg/mL, respectively.

Antimicrobial and Efflux Inhibitor Activity of Usnic Acid Against Mycobacterium abscessus.

PubMed

Ramis, Ivy B; Vianna, Júlia S; Reis, Ana Júlia; von Groll, Andrea; Ramos, Daniela F; Viveiros, Miguel; da Silva, Pedro E Almeida

2018-06-18

New drugs are needed to treat infections with antimicrobial-resistant Mycobacterium abscessus ; therefore, we evaluated usnic acid as an antimicrobial agent and efflux inhibitor (EI) against M. abscessus . Usnic acid showed antimicrobial activity, and synergistically, the EI verapamil increased this activity. In addition, when we evaluated the interaction of antimicrobials with usnic acid, the increase of their activity was observed. Finally, usnic acid showed an efflux inhibitory effect between the classical EIs verapamil and carbonyl cyanide m-chlorophenylhydrazine. In conclusion, usnic acid showed both antimicrobial and EI activity, indicating that this natural compound may be a promising scaffold for new drugs against this difficult-to-treat microorganism. Georg Thieme Verlag KG Stuttgart · New York.

Antibacterial activity of different honeys against pathogenic bacteria.

PubMed

Voidarou, C; Alexopoulos, A; Plessas, S; Karapanou, A; Mantzourani, I; Stavropoulou, E; Fotou, K; Tzora, A; Skoufos, I; Bezirtzoglou, E

2011-12-01

To study the antimicrobial activity of honey, 60 samples of various botanical origin were evaluated for their antimicrobial activities against 16 clinical pathogens and their respective reference strains. The microbiological quality of honeys and the antibiotic susceptibility of the various isolates were also examined. The bioassay applied for determining the antimicrobial effect employs the well-agar diffusion method and the estimation of minimum active dilution which produces a 1mm diameter inhibition zone. All honey samples, despite their origin (coniferous, citrus, thyme or polyfloral), showed antibacterial activity against the pathogenic and their respective reference strains at variable levels. Coniferous and thyme honeys showed the highest activity with an average minimum dilution of 17.4 and 19.2% (w/v) followed by citrus and polyfloral honeys with 20.8 and 23.8% respectively. Clinical isolates of Staphylococcus aureus subsp. aureus, Escherichia coli, Salmonella enterica subsp. Enterica, Streptococcus pyogenes, Bacillus cereus and Bacillus subtilis were proven to be up to 60% more resistant than their equal reference strains thus emphasizing the variability in the antibacterial effect of honey and the need for further research. Copyright © 2011 Elsevier Ltd. All rights reserved.

Which Approach Is More Effective in the Selection of Plants with Antimicrobial Activity?

PubMed Central

Silva, Ana Carolina Oliveira; Santana, Elidiane Fonseca; Saraiva, Antonio Marcos; Coutinho, Felipe Neves; Castro, Ricardo Henrique Acre; Pisciottano, Maria Nelly Caetano; Amorim, Elba Lúcia Cavalcanti; Albuquerque, Ulysses Paulino

2013-01-01

The development of the present study was based on selections using random, direct ethnopharmacological, and indirect ethnopharmacological approaches, aiming to evaluate which method is the best for bioprospecting new antimicrobial plant drugs. A crude extract of 53 species of herbaceous plants collected in the semiarid region of Northeast Brazil was tested against 11 microorganisms. Well-agar diffusion and minimum inhibitory concentration (MIC) techniques were used. Ten extracts from direct, six from random, and three from indirect ethnopharmacological selections exhibited activities that ranged from weak to very active against the organisms tested. The strain most susceptible to the evaluated extracts was Staphylococcus aureus. The MIC analysis revealed the best result for the direct ethnopharmacological approach, considering that some species yielded extracts classified as active or moderately active (MICs between 250 and 1000 µg/mL). Furthermore, one species from this approach inhibited the growth of the three Candida strains. Thus, it was concluded that the direct ethnopharmacological approach is the most effective when selecting species for bioprospecting new plant drugs with antimicrobial activities. PMID:23878595

Antibiofilm Activity of the Brown Alga Halidrys siliquosa against Clinically Relevant Human Pathogens

PubMed Central

Busetti, Alessandro; Thompson, Thomas P.; Tegazzini, Diana; Megaw, Julianne; Maggs, Christine A.; Gilmore, Brendan F.

2015-01-01

The marine brown alga Halidrys siliquosa is known to produce compounds with antifouling activity against several marine bacteria. The aim of this study was to evaluate the antimicrobial and antibiofilm activity of organic extracts obtained from the marine brown alga H. siliquosa against a focused panel of clinically relevant human pathogens commonly associated with biofilm-related infections. The partially fractionated methanolic extract obtained from H. siliquosa collected along the shores of Co. Donegal; Ireland; displayed antimicrobial activity against bacteria of the genus Staphylococcus; Streptococcus; Enterococcus; Pseudomonas; Stenotrophomonas; and Chromobacterium with MIC and MBC values ranging from 0.0391 to 5 mg/mL. Biofilms of S. aureus MRSA were found to be susceptible to the algal methanolic extract with MBEC values ranging from 1.25 mg/mL to 5 mg/mL respectively. Confocal laser scanning microscopy using LIVE/DEAD staining confirmed the antimicrobial nature of the antibiofilm activity observed using the MBEC assay. A bioassay-guided fractionation method was developed yielding 10 active fractions from which to perform purification and structural elucidation of clinically-relevant antibiofilm compounds. PMID:26058011

The constituents of essential oil: antimicrobial and antioxidant activity of Micromeria congesta Boiss. & Hausskn. ex Boiss. from East Anatolia.

PubMed

Herken, Emine Nur; Celik, Ali; Aslan, Mustafa; Aydınlık, Nilüfer

2012-09-01

The chemical composition, antimicrobial activity, total phenol content, total antioxidant activity, and total oxidant status of the essential oil from Micromeria congesta Boiss. & Hausskn. ex Boiss. were investigated. Steam distillation was used to obtain the essential oil, and the chemical analyses were performed by gas chromatography-mass spectrometry. The antimicrobial activity was tested by an agar disc diffusion method against the tested microorganisms: Bacillus subtilis NRRL B-744, Bacillus cereus NRRL B-3711, Staphylococcus aureus ATCC 12598, S. aureus ATCC 25923, S. aureus ATCC 25933, Escherichia coli 0157H7, E. coli ATCC25922, Micrococcus luteus NRLL B-4375, Enterococcus faecalis ATCC 19433, Proteus vulgaris RSKK 96026, and Yersinia enterecolitica RSKK 1501. The major compounds found in volatiles of M. congesta were piperitone oxide, linalool oxide, veratrole, pulegone, dihydro carvone, naphthalene, iso-menthone, para-menthone, and cyclohexanone. Compared to that of reference antibiotics, the antibacterial activity of the essential oil is considered as significant. Results showed that M. congesta has the potential for being used in food and medicine depending on its antioxidant and antibacterial activity.

Immortelle (Xeranthemum annuum L.) as a natural source of biologically active substances

PubMed Central

Stankovic, Milan S.; Radojevic, Ivana D.; Stefanovic, Olgica D.; Topuzovic, Marina D.; Comic, Ljiljana R.; Brankovic, Snežana R.

2011-01-01

Antioxidant and antimicrobial effects, total phenolic content and flavonoid concentrations of methanolic, acetone and ethyl acetate extracts from Xeranthemum annuum L. were investigated in this study. The total phenolic content was determined using Folin-Ciocalteu reagent and ranged between 101.33 to 159.48 mg GA/g. The concentration of flavonoids in various X. annuum extracts was determined using spectrophotometric method with aluminum chloride and the results varied from 22.25 to 62.42 mg RU/g. Antioxidant activity was monitored spectrophotometrically using DPPH reagent and expressed in terms of IC50 (µg/ml), and it ranged from 59.25 to 956.81 µg/ml. The highest phenolic content and capacity to neutralize DPPH radicals were found in the acetone extract. In vitro antimicrobial activity was determined by microdilution method. Minimum inhibitory concentration (MIC) and minimum microbicidal concentration (MMC) have been determined. Testing was conducted against 24 microorganisms, including 15 strains of bacteria (standard and clinical strains) and 9 species of fungi. Statistically significant difference in activity between the extracts of X. annuum L. was observed and the acetone extract was found most active. The activity of acetone extract was in accordance with total phenol content and flavonoid concentration measured in this extract. The tested extracts showed significant antibacterial activity against G+ bacteria and weak to moderate activity against other microorganisms. Based on the obtained results, X. annuum can be considered as a rich natural source of polyphenolic compounds with very good antioxidant and antimicrobial activity. PMID:27857677

Synthesis, Antimicrobial, and Antioxidant Activities of Chalcogen-Containing Nitrone Derivatives from (R)-citronellal

PubMed Central

Ferraz, Mariana C.; Mano, Renata A.; Oliveira, Daniela H.; Maia, Darla S. V.; Silva, Wladimir P.; Savegnago, Lucielli; Lenardão, Eder J.; Jacob, Raquel G.

2017-01-01

Background: The main constituents of Cymbopogonnardus (L) Rendle and C. citratus (DC) Stapfessential oils are (R)-citronellal and citral, respectively. Organochalcogen compounds can boost the biological activities of natural products. Methods: Several chalcogen-containing nitrones derived from (R)-citronellal and citral were prepared and evaluated for their antimicrobial and antioxidant activities. The antimicrobial activity was evaluated by the disc diffusion test and the antioxidant properties were evaluated in vitro by DPPH (1,1-diphenyl-2-picryl-hydrazyl), ABTS (2,2′-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid), and FRAP (ferric ion reducing antioxidant power) assays. Results: In the antimicrobial assay, (E)-N,3,7-trimethyl-3-(phenylthio)oct-6-en-1-imine oxide 5c exhibited halos between 21.5 mm (Escherichia coli O157:H7) and 26.0 mm (Listeria monocytogenes), while (E)-N,3,7-trimethyloct-6-en-1-imine oxide 5d presented halos between 22.5 mm (E. coli O157:H7) and 31.0 mm (L. monocytogenes). (E)-N,3,7-Trimethyl-2-(phenylthio)oct-6-en-1-imine oxide 5a showed the lowest minimal inhibitory concentration (MIC) value against Bacillus cereus (0.48 mM), and 5c was the most potent bactericide, with a minimal bactericidal concentration (MBC) of 0.52 mM for E. coli O157:H7. In the antioxidant assays, 5c, 5d, and 10 ((E)-3,7-dimethyl-2-(phenylselanyl)oct-6-enal oxime) were the most actives in the DPPH, ABTS, and FRAP assays, respectively. Conclusions: The presence of a phenylthio group in the nitrone increases its antimicrobial activity against Gram-positive and Gram-negative foodborne pathogens in the disk diffusion test and the antioxidant activity in vitro. PMID:28930254

The use of unirradiated and γ-irradiated zinc oxide nanoparticles as a preservative in cosmetic preparations

PubMed Central

Hosny, Alaa El-Dien MS; Kashef, Mona T; Taher, Hadeer A; El-Bazza, Zeinab E

2017-01-01

Purpose Microbial contamination of different cosmetic preparations, as a result of preservative failure, presents a major public health threat. Also, most of the known preservatives have serious consumer side effects. The antimicrobial activity of zinc oxide nanoparticles (ZnO NP) is well documented. Therefore, we aimed to determine the possible use of unirradiated and γ-irradiated ZnO NP as a cosmetic preservative. Methods The possible use of ZnO NP as a preservative was tested and compared to commonly used preservatives using a challenge test. Their activity was tested in six different types of preparations. The effect of γ radiation on the antimicrobial activity of ZnO NP was tested through determination of the obtained zone diameters against different microorganisms and the total aerobic microbial count in tested preparations. The antimicrobial activity, of unirradiated and γ-irradiated ZnO NP during storage was also determined. Results ZnO NP were superior to other commonly used preservatives in all tested cosmetic preparations. They pass the challenge test in all types of tested preparations. γ irradiation enhanced their antimicrobial activity in all tested preparations. The irradiation causes a reduction in NP sizes that is directly proportional to the applied radiation dose. Upon storage, ZnO NP were effective in maintaining the microbial count of the product within the acceptable range. Their activity in stored products was enhanced by γ irradiation. Conclusion Unirradiated and γ-irradiated ZnO NP can be used as effective preservatives. They are compatible with the components of all tested products. γ irradiation enhanced the antimicrobial activity of ZnO NP. PMID:28979119

Screening of in vitro antimicrobial activity of plants used in traditional Indonesian medicine.

PubMed

Romulo, Andreas; Zuhud, Ervizal A M; Rondevaldova, Johana; Kokoska, Ladislav

2018-12-01

In many regions of Indonesia, there are numerous traditional herbal preparations for treatment of infectious diseases. However, their antimicrobial potential has been poorly studied by modern laboratory methods. This study investigates in vitro antimicrobial activity of 49 ethanol extracts from 37 plant species used in Indonesian traditional medicine for treatment against Candida albicans, Enterococcus faecalis, Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus. The plants were collected from the Biopharmaca collection garden, Bogor, Indonesia. The plant material was dried, finely grounded, extracted using ethanol, concentrated, and the dried residue was dissolved in 100% DMSO. Antimicrobial activity was determined in terms of a minimum inhibitory concentration (MIC) using a broth microdilution method in 96-well microplates. The extract of Orthosiphon aristatus (Blume) Miq. (Lamiaceae) leaf produced the strongest antimicrobial effect, inhibiting the growth of C. albicans (MIC 128 μg/mL), S. aureus (MIC 256 μg/mL), E. faecalis (MIC 256 μg/mL) and P. aeruginosa (MIC 256 μg/mL). The leaf extract of Woodfordia floribunda Salisb. (Lythraceae) also exhibited significant effect against C. albicans (MIC 128 μg/mL), S. aureus (MIC 256 μg/mL) and E. faecalis (MIC 256 μg/mL). Rotheca serrata (L.) Steane & Mabb. (Lamiaceae) leaf extract inhibited the growth of S. aureus (MIC 256 µg/mL) and C. albicans (MIC 256 µg/mL). The leaf extract of O. aristatus and W. floribunda exhibited a significant anti-candidal effect. Therefore, both of these plants can serve as prospective source materials for the development of new anti-candidal agents.

Biosynthesis of silver nanoparticles using Plectranthus amboinicus leaf extract and its antimicrobial activity

NASA Astrophysics Data System (ADS)

Ajitha, B.; Ashok Kumar Reddy, Y.; Sreedhara Reddy, P.

2014-07-01

This study reports the simple green synthesis method for the preparation of silver nanoparticles (Ag NPs) using Plectranthus amboinicus leaf extract. The pathway of nanoparticles formation is by means of reduction of AgNO3 by leaf extract, which acts as both reducing and capping agents. Synthesized Ag NPs were subjected to different characterizations for studying the structural, chemical, morphological, optical and antimicrobial properties. The bright circular fringes in SAED pattern and diffraction peaks in XRD profile reveals high crystalline nature of biosynthesized Ag NPs. Morphological studies shows the formation of nearly spherical nanoparticles. FTIR spectrum confirms the existence of various functional groups of biomolecules capping the nanoparticles. UV-visible spectrum displays single SPR band at 428 nm indicating the absence of anisotropic particles. The synthesized Ag NPs exhibited better antimicrobial property towards gram negative Escherichia coli and towards tested Penicillium spp. than other tested microorganisms using disc diffusion method. Finally it has proven that the synthesized bio-inspired Ag NPs have potent antimicrobial effect.

Antibacterial activity of essential oils extracted from Satureja hortensis against selected clinical pathogens

NASA Astrophysics Data System (ADS)

Görmez, Arzu; Yanmiş, Derya; Bozari, Sedat; Gürkök, Sumeyra

2017-04-01

The antibiotic resistance of pathogenic microorganisms has become a worldwide concern to public health. To overcome the current resistance problem, new antimicrobial agents are extremely needed. The aim of the present study was to evaluate the antibacterial activity of Satureja hortensis essential oils against seven clinical pathogens. Chemical compositions of hydro distillated essential oils from S. hortensis were analyzed by GS-MS. The antibacterial activity was investigated against Corynebacterium diphtheria, Salmonella typhimurium, Serratia plymuthica Yersinia enterocolitica, Y. frederiksenii, Y. pseudotuberculosis and Vibrio cholerae by the use of disc diffusion method and broth micro dilution method. The minimum inhibitory concentration (MIC) values of essential oils were found as low as 7.81 µg/mL. Notably, essential oils of S. hortensis exhibited remarkable antimicrobial activities against the tested clinical pathogens. The results indicate that these essential oils can be used in treatment of different infectious diseases.

Salivary defense system alters in vegetarian

PubMed Central

Amirmozafari, Nour; Pourghafar, Houra; Sariri, Reyhaneh

2013-01-01

Purpose The aim of this research was investigating antimicrobial and enzymatic antioxidant activities in salivary fluids of vegetarians as compared to normal subjects. Material & Methods Antimicrobial activity of the saliva samples was evaluated against four clinically important bacteria. The biological activities of three of the main antioxidant enzymes of saliva were measured using appropriate methods of enzyme assay in both groups. Results According to the results, saliva obtained from vegetarians showed a reduced inhibitory effect on growth of Staphylococcus aureus, Klebsiella oxytoca, Pseudomonas aeruginosa and Escherichia coli as compared to those obtained from the non-vegetarian subjects. The activity of salivary peroxidase, catalase and superoxide dismutase showed a statistically marked decrease in vegetarian group. Conclusions According to our literature survey, this is the first report on the antibacterial and antioxidant capacity in saliva of vegetarians. Results obtained from the present study have opened a new line of research with the basis of saliva as a research tool. PMID:25737889

The Integral Method, a new approach to quantify bactericidal activity.

PubMed

Gottardi, Waldemar; Pfleiderer, Jörg; Nagl, Markus

2015-08-01

The bactericidal activity (BA) of antimicrobial agents is generally derived from the results of killing assays. A reliable quantitative characterization and particularly a comparison of these substances, however, are impossible with this information. We here propose a new method that takes into account the course of the complete killing curve for assaying BA and that allows a clear-cut quantitative comparison of antimicrobial agents with only one number. The new Integral Method, based on the reciprocal area below the killing curve, reliably calculates an average BA [log10 CFU/min] and, by implementation of the agent's concentration C, the average specific bactericidal activity SBA=BA/C [log10 CFU/min/mM]. Based on experimental killing data, the pertaining BA and SBA values of exemplary active halogen compounds were established, allowing quantitative assertions. N-chlorotaurine (NCT), chloramine T (CAT), monochloramine (NH2Cl), and iodine (I2) showed extremely diverging SBA values of 0.0020±0.0005, 1.11±0.15, 3.49±0.22, and 291±137log10 CFU/min/mM, respectively, against Staphylococcus aureus. This immediately demonstrates an approximately 550-fold stronger activity of CAT, 1730-fold of NH2Cl, and 150,000-fold of I2 compared to NCT. The inferred quantitative assertions and conclusions prove the new method suitable for characterizing bactericidal activity. Its application comprises the effect of defined agents on various bacteria, the consequence of temperature shifts, the influence of varying drug structure, dose-effect relationships, ranking of isosteric agents, comparison of competing commercial antimicrobial formulations, and the effect of additives. Copyright © 2015 Elsevier B.V. All rights reserved.

Foeniculum vulgare essential oils: chemical composition, antioxidant and antimicrobial activities.

PubMed

Miguel, Maria Graça; Cruz, Cláudia; Faleiro, Leonor; Simões, Mariana T F; Figueiredo, Ana Cristina; Barroso, José G; Pedro, Luis G

2010-02-01

The essential oils from Foeniculum vulgare commercial aerial parts and fruits were isolated by hydrodistillation, with different distillation times (30 min, 1 h, 2 h and 3 h), and analyzed by GC and GC-MS. The antioxidant ability was estimated using four distinct methods. Antibacterial activity was determined by the agar diffusion method. Remarkable differences, and worrying from the quality and safety point of view, were detected in the essential oils. trans-Anethole (31-36%), alpha-pinene (14-20%) and limonene (11-13%) were the main components of the essentials oil isolated from F. vulgare dried aerial parts, whereas methyl chavicol (= estragole) (79-88%) was dominant in the fruit oils. With the DPPH method the plant oils showed better antioxidant activity than the fruits oils. With the TBARS method and at higher concentrations, fennel essential oils showed a pro-oxidant activity. None of the oils showed a hydroxyl radical scavenging capacity > 50%, but they showed an ability to inhibit 5-lipoxygenase. The essential oils showed a very low antimicrobial activity. In general, the essential oils isolated during 2 h were as effective, from the biological activity point of view, as those isolated during 3 h.

Extracts of Agrimonia eupatoria L. as sources of biologically active compounds and evaluation of their antioxidant, antimicrobial, and antibiofilm activities.

PubMed

Muruzović, Mirjana Ž; Mladenović, Katarina G; Stefanović, Olgica D; Vasić, Sava M; Čomić, Ljiljana R

2016-07-01

In this study, we determined the concentration of total phenols, flavonoids, tannins, and proanthocyanidins in the water, diethyl ether, acetone, and ethanol extracts of Agrimonia eupatoria L. We also investigated the antioxidant activity of these extracts using two methods [2,2-diphenyl-1-picrylhydrazyl (DPPH) and reducing power] and their in vitro antimicrobial (antibacterial and antifungal) activity on some selected species of bacteria and fungi. In addition, the effects of the acetone and water extracts on the inhibition of biofilm formation of Proteus mirabilis and Pseudomonas aeruginosa were investigated using the crystal violet method. The concentration of total phenols was measured according to the Folin-Ciocalteu method and the values obtained ranged from 19.61 mgGA/g to 220.31 mgGA/g. The concentration of flavonoids was examined by the aluminum chloride method and the values obtained ranged from 20.58 mgRU/g to 97.06 mgRU/g. The total tannins concentration was measured by the polyvinylpolypyrrolidone method and the values obtained ranged from 3.06 mgGA/g to 207.27 mgGA/g. The concentration of proanthocyanidins was determined by the butanol-HCl method and the values obtained ranged from 4.15 CChE/g to 103.72 CChE/g. Among the various extracts studied, the acetone extract exhibited good antioxidant activity (97.13%, as determined by the DPPH method). The acetone extract was active in the absorbance value range from 2.2665 to 0.2495 (as determined by the reducing power method). The strongest antimicrobial activity was detected on G + bacteria, especially on probiotic species, and the acetone extract demonstrated the highest activity. Biofilm inhibitory concentration required to reduce biofilm coverage by 50% values for acetone extract was 4315 μg/mL for P. mirabilis and 4469.5 μg/mL for P. aeruginosa. The results provide a basis for further research of this plant species. Copyright © 2016. Published by Elsevier B.V.

Antimicrobial and cytotoxic activity of red propolis: an alert for its safe use.

PubMed

Lopez, B G-C; de Lourenço, C C; Alves, D A; Machado, D; Lancellotti, M; Sawaya, A C H F

2015-09-01

Red propolis is a resinous product popularly consumed in Brazil as it improves health, and it is considered a nutraceutical. The objective of this study was to test the antimicrobial activity of eight samples of red propolis from Brazil and Cuba to assess the possibility of application of this natural product as an antimicrobial agent, along with a study of its cytotoxic activity against non-tumor cell lines to evaluate at which concentrations it could be safely used. The chemical profile of the samples was evaluated by UHPLC-MS. All the samples presented antimicrobial activity which was tested using agar diffusion and serial dilution methods; and these samples displayed a better activity against most Gram-negative bacteria with minimum inhibitory concentration (MIC) in the range between 6·25 μg ml(-1) and 500 μg ml(-1). However our studies also revealed an inherent cytotoxic effect against HaCaT human keratinocytes and BALBc 3T3. To have a noncytotoxic and safe use of red propolis, it is necessary to use a concentration below the IC50 cytotoxic values. The traditional use of propolis does not necessarily guarantee its safety. The evaluation of the safety of bioactive natural products should always be considered together with the evaluation of the activity. © 2015 The Society for Applied Microbiology.

The in-vitro evaluation of antibacterial, antifungal and cytotoxic properties of Marrubium vulgare L. essential oil grown in Tunisia

PubMed Central

2011-01-01

Background In order to validate its antiseptic and anticancer properties with respect to traditional uses, we have screened for the first time the antimicrobial activity of aerial parts of M. vulgare L. essential oil against different pathogenic microorganisms and the cytotoxic activity against HeLa cell lines. Methods The agar disk diffusion method was used to study the antibacterial activity of M. vulgare essential oil against 12 bacterial and 4 fungi strains. The disc diameters of zone of inhibition (DD), the minimum inhibitory concentrations (MIC) and the concentration inhibiting 50% (IC50) were investigated to characterize the antimicrobial activities of this essential oil. The in vitro cytotoxicity of M. vulgare essential oil was examined using a modified MTT assay; the viability and the IC50 were used to evaluate this test. Results The antimicrobial activity of the essential oil was investigated in order to evaluate its efficacy against the different tested microorganisms. The present results results showed a significant activity against microorganisms especially Gram (+) bacteria with inhibition zones and minimal inhibitory concentration values in the range of 6.6-25.2 mm and 1120-2600 μg/ml, respectively, whereas Gram (-) bacteria exhibited a higher resistance. As far as the antifungal activity, among four strains tested, Botrytis cinerea exhibited the strongest activity with inhibition zones of 12.6 mm. However, Fusarium solani, Penicillium digitatum and Aspergillus niger were less sensitive to M. vulgare essential oil. About the citotoxicity assay, this finding indicate the capability of this essential oil to inhibited the proliferation of HeLa cell lines under some conditions with IC50 value of 0.258 μg/ml. Conclusion This investigation showed that the M. vulgare essential oil has a potent antimicrobial activity against some Gram (+) pathogenic bacteria and Botrytis cinerea fungi. The present studies confirm the use of this essential oil as anticancer agent. Further research is required to evaluate the practical values of therapeutic applications. PMID:21936887

In-vitro antimicrobial activity of marine actinobacteria against multidrug resistance Staphylococcus aureus

PubMed Central

Sathish, Kumar SR; Kokati, Venkata Bhaskara Rao

2012-01-01

Objective To investigate the antibacterial activity of marine actinobacteria against multidrug resistance Staphylococcus aureus (MDRSA). Methods Fifty one actinobacterial strains were isolated from salt pans soil, costal area in Kothapattanam, Ongole, Andhra Pradesh. Primary screening was done using cross-streak method against MDRSA. The bioactive compounds are extracted from efficient actinobacteria using solvent extraction. The antimicrobial activity of crude and solvent extracts was performed using Kirby-Bauer method. MIC for ethyl acetate extract was determined by modified agar well diffusion method. The potent actinobacteria are identified using Nonomura key, Shirling and Gottlieb 1966 with Bergey's manual of determinative bacteriology. Results Among the fifty one isolates screened for antibacterial activity, SRB25 were found efficient against MDRSA. The ethyl acetate extracts showed high inhibition against test organism. MIC test was performed with the ethyl acetate extract against MDRSA and found to be 1 000 µg/mL. The isolated actinobacteria are identified as Streptomyces sp with the help of Nonomura key. Conclusions The current investigation reveals that the marine actinobacteria from salt pan environment can be able to produce new drug molecules against drug resistant microorganisms. PMID:23569848

Antimicrobial activity of fluoride and its in vivo importance: identification of research questions.

PubMed

Van Loveren, C

2001-01-01

This manuscript discusses the antimicrobial activity of fluoride and its in vivo importance in order to identify research questions. There is a lot of information on mechanisms by which fluoride may interfere with bacterial metabolism and dental plaque acidogenicity. The antimicrobial activity of fluoride products is enhanced when fluoride is associated with antimicrobial cations like Sn(2+) and amine. It is not clear whether the antimicrobial mechanisms of fluoride are operating in vivo or even to what extent antimicrobial activity can contribute to caries prevention. This latter question may be the most important one in research. Copyright 2001 S. Karger AG, Basel.

Antimicrobial activity of pomegranate peel extracts as affected by cultivar.

PubMed

Rosas-Burgos, Ema C; Burgos-Hernández, Armando; Noguera-Artiaga, Luis; Kačániová, Miroslava; Hernández-García, Francisca; Cárdenas-López, José L; Carbonell-Barrachina, Ángel A

2017-02-01

Some studies have reported that different parts of the pomegranate fruit, especially the peel, may act as potential antimicrobial agents and thus might be proposed as a safe natural alternative to synthetic antimicrobial agents. The high tannin content, especially punicalagin, found in pomegranate extracts, has been reported as the main compound responsible for such antimicrobial activity. Because the pomegranate peel chemical composition may vary with the type of cultivar (sweet, sour-sweet and sour), pomegranates may also differ with respect to their antimicrobial capacity. The extract from PTO8 pomegranate cultivar peel had the highest antimicrobial activity, as well as the highest punicalagins (α and β) and ellagic acid concentrations. In the results obtained from both antibacterial and antifungal activity studies, the sour-sweet pomegranate cultivar PTO8 showed the best antimicrobial activity, and the highest ellagic acid concentrations. The results of the present study suggest that ellagic acid content has a significant influence on the antimicrobial activity of the pomegranate extracts investigated. The pomegranate peel of the PTO8 cultivar is a good source of antifungal and antibacterial compounds, and may represent an alternative to antimicrobial agents of synthetic origin. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Antimicrobial activity of Eucalyptus camaldulensis essential oils and their interactions with conventional antimicrobial agents against multi-drug resistant Acinetobacter baumannii.

PubMed

Knezevic, Petar; Aleksic, Verica; Simin, Natasa; Svircev, Emilija; Petrovic, Aleksandra; Mimica-Dukic, Neda

2016-02-03

Traditional herbal medicine has become an important issue on the global scale during the past decade. Among drugs of natural origin, special place belongs to essential oils, known as strong antimicrobial agents that can be used to combat antibiotic-resistant bacteria. Eucalyptus camaldulensis leaves are traditional herbal remedy used for various purposes, including treatment of infections. The aim of this study was to determine antimicrobial potential of two E. camaldulensis essential oils against multi-drug resistant (MDR) Acinetobacter baumannii wound isolates and to examine possible interactions of essential oils with conventional antimicrobial agents. Chemical composition of essential oils was determined by gas chromatography-mass spectrometry analysis (GC-MS). MIC values of essential oils against A. baumannii strains were estimated by modified broth microdilution method. The components responsible for antimicrobial activity were detected by bioautographic analysis. The potential synergy between the essential oils and antibiotics (ciprofloxacin, gentamicin and polymyxin B) was examined by checkerboard method and time kill curve. The dominant components of both essential oils were spatulenol, cryptone, p-cimene, 1,8-cineole, terpinen-4-ol and β-pinene. The detected MICs for the E. camaldulensis essential oils were in range from 0.5 to 2 μl mL(-1). The bioautographic assay confirmed antibacterial activity of polar terpene compounds. In combination with conventional antibiotics (ciprofloxacin, gentamicin and polymyxin B), the examined essential oils showed synergistic antibacterial effect in most of the cases, while in some even re-sensitized MDR A. baumannii strains. The synergistic interaction was confirmed by time-kill curves for E. camaldulensis essential oil and polymyxin B combination which reduced bacterial count under detection limit very fast, i.e. after 6h of incubation. The detected anti-A. baumannii activity of E. camaldulensis essential oils justifies traditional use of this plant. The proven E. camaldulensis essential oil synergistic interactions with conventional antibiotics could lead to the development of new treatment strategies of infections caused by MDR A. baumannii strains in the term of antibiotic dose reduction. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Overcoming Antimicrobial Resistance in Bacteria Using Bioactive Magnetic Nanoparticles and Pulsed Electromagnetic Fields

PubMed Central

Novickij, Vitalij; Stanevičienė, Ramunė; Vepštaitė-Monstavičė, Iglė; Gruškienė, Rūta; Krivorotova, Tatjana; Sereikaitė, Jolanta; Novickij, Jurij; Servienė, Elena

2018-01-01

Nisin is a known bacteriocin, which exhibits a wide spectrum of antimicrobial activity, while commonly being inefficient against Gram-negative bacteria. In this work, we present a proof of concept of novel antimicrobial methodology using targeted magnetic nisin-loaded nano-carriers [iron oxide nanoparticles (NPs) (11–13 nm) capped with citric, ascorbic, and gallic acids], which are activated by high pulsed electric and electromagnetic fields allowing to overcome the nisin-resistance of bacteria. As a cell model the Gram-positive bacteria Bacillus subtilis and Gram-negative Escherichia coli were used. We have applied 10 and 30 kV cm-1 electric field pulses (100 μs × 8) separately and in combination with two pulsed magnetic field protocols: (1) high dB/dt 3.3 T × 50 and (2) 10 mT, 100 kHz, 2 min protocol to induce additional permeabilization and local magnetic hyperthermia. We have shown that the high dB/dt pulsed magnetic fields increase the antimicrobial efficiency of nisin NPs similar to electroporation or magnetic hyperthermia methods and a synergistic treatment is also possible. The results of our work are promising for the development of new methods for treatment of the drug-resistant foodborne pathogens to minimize the risks of invasive infections. PMID:29375537

Overcoming Antimicrobial Resistance in Bacteria Using Bioactive Magnetic Nanoparticles and Pulsed Electromagnetic Fields.

PubMed

Novickij, Vitalij; Stanevičienė, Ramunė; Vepštaitė-Monstavičė, Iglė; Gruškienė, Rūta; Krivorotova, Tatjana; Sereikaitė, Jolanta; Novickij, Jurij; Servienė, Elena

2017-01-01

Nisin is a known bacteriocin, which exhibits a wide spectrum of antimicrobial activity, while commonly being inefficient against Gram-negative bacteria. In this work, we present a proof of concept of novel antimicrobial methodology using targeted magnetic nisin-loaded nano-carriers [iron oxide nanoparticles (NPs) (11-13 nm) capped with citric, ascorbic, and gallic acids], which are activated by high pulsed electric and electromagnetic fields allowing to overcome the nisin-resistance of bacteria. As a cell model the Gram-positive bacteria Bacillus subtilis and Gram-negative Escherichia coli were used. We have applied 10 and 30 kV cm -1 electric field pulses (100 μs × 8) separately and in combination with two pulsed magnetic field protocols: (1) high d B /d t 3.3 T × 50 and (2) 10 mT, 100 kHz, 2 min protocol to induce additional permeabilization and local magnetic hyperthermia. We have shown that the high d B /d t pulsed magnetic fields increase the antimicrobial efficiency of nisin NPs similar to electroporation or magnetic hyperthermia methods and a synergistic treatment is also possible. The results of our work are promising for the development of new methods for treatment of the drug-resistant foodborne pathogens to minimize the risks of invasive infections.

The synergistic preservative effects of the essential oils of sweet basil (Ocimum basilicum L.) against acid-tolerant food microflora.

PubMed

Lachowicz, K J; Jones, G P; Briggs, D R; Bienvenu, F E; Wan, J; Wilcock, A; Coventry, M J

1998-03-01

Essential oils extracted by hydrodistillation from five different varieties of Ocimum basilicum L. plants (Anise, Bush, Cinnamon, Dark Opal and a commercial sample of dried basil) were examined for antimicrobial activity against a wide range of foodborne Gram-positive and -negative bacteria, yeasts and moulds by an agar well diffusion method. All five essential oils of basil showed antimicrobial activity against most of the organisms tested with the exception of Flavimonas oryzihabitans and Pseudomonas species. The inhibitory effect of Anise oil, in comparison with mixtures of the predominant components of pure linalool and methyl chavicol, against the acid-tolerant organisms, Lactobacillus curvatus and Saccharomyces cerevisiae, was examined in broth by an indirect impedance method. Synergistic effects between Anise oil, low pH (pH 4.2) and salt (5% NaCl) were determined. The antimicrobial effect of Anise oil was also assessed in a tomato juice medium by direct viable count, showing that the growth of Lact. curvatus and S. cerevisiae was completely inhibited by 0.1% and 1% Anise oil, respectively. The results of the current study indicate the need for further investigations to understand the antimicrobial effects of basil oils in the presence of other food ingredients and preservation parameters.

Chrysen-2-ol derivative from West Indian Wood Nettle Laportea aestuans (L.) Chew inhibits oxidation and microbial growth in vitro

PubMed Central

Oloyede, Ganiyat K.; Oyelola, Martha S.

2013-01-01

Bio-active compounds present in West Indian Wood Nettle Laportea aestuans (L.) Chew (Urticaceae), used in ethno medicine as antioxidant and antimicrobial were studied. The aim of this research work was to isolate and characterize the bio-active compounds in the n-hexane fraction of L. aestuans, determine the toxicity and subject it to in-vitro antimicrobial and free radical scavenging activities. The chemical constituents were isolated by gradient elution column chromatographic technique and Ultra Violet/visible (UV), Infrared (IR) and Nuclear Magnetic Resonance (NMR) spectroscopies were used for structural elucidation. The free radical scavenging activity of the isolate was assessed using three methods; scavenging effect on 2,2-diphenyl-1-picrylhydrazyl radical (DPPH), hydroxyl radical generated from hydrogen peroxide and ferric thiocynate method. Antimicrobial screening was done by agar well diffusion method while toxicity was determined by Brine shrimp lethality test. Structures were proposed for the white crystalline solids isolated; (4E)-3,6-dimethylhep-4-en-3-ol (AB) and 1,2,3,4,4a,4b,5,6,6a,7,8,9,10,10a,10b,11-hexadecahydro-1,1,6a,10b-tetramethyl-7-((E)-4,7-dimethyloct-5-enyl) chrysen-2-ol (AC). Percentage yield of AC was 91.2 and was non-toxic with LC50 (µg/ml) value of 1581233000.0. AC significantly scavenged free radical at 0.0625 mg/ml in the DPPH (64.73 %) and hydrogen peroxide (99.22 %) tests. It also showed 65.23 % inhibition at 1.0 mg/ml in the ferric thiocyanate test. AC also inhibited microbial growth significantly when compared with gentamicin and tioconazole which are antibacterial and antifungal standards respectively. The presence of Chrysen-2-ol derivative in L. aestuans which was non-toxic and possessed significant antimicrobial and antioxidant activities supports its ethno medicinal application. PMID:27092035

Antimicrobial activity of stingless bee (Trigona sp.) propolis used in the folk medicine of Western Maharashtra, India.

PubMed

Choudhari, Milind K; Punekar, Sachin A; Ranade, Ramchandra V; Paknikar, Kishore M

2012-05-07

Stingless bee (Trigona sp.) propolis is widely used in the folk medicine of Western Maharashtra, India to treat a variety of ailments. To determine the chemical composition and evaluate the antimicrobial activity of Indian stingless bee propolis. Chemical composition of the ethanolic extract of propolis (EEP) was determined by GC-MS analysis. A range of bacteria including multidrug resistant (MDR) cultures as well as a yeast strain was tested for antimicrobial activity using EEP. MIC, MBC, MFC, Kill curves and post agent effect (PAE) of the EEP were assessed using standard microbiological methods. GC-MS analysis revealed that propolis contained 24 compounds (9 known and 15 newly reported). Many of these were known bioactive compounds, including antimicrobials. The MICs of EEP were in the range of 1.21-9.75μg/mL while the MBCs/MFC were between 2.43 and 19.5μg/mL. The time required to achieve 90% (1 log(10)) reduction in culture growth ranged between 1.06 and 3.53h at their respective MIC values. PAE for all the cultures was >24h. Indian stingless bee propolis has a complex nature with 24 chemical compounds. It has a potent broad-spectrum antimicrobial activity. The latter finding, in conjunction with other bioactive properties, could provide a scientific basis to its popular use in the Indian folk medicine. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Phytochemical, toxicological and antimicrobial evaluation of lawsonia inermis extracts against clinical isolates of pathogenic bacteria

PubMed Central

2013-01-01

Background The emerging resistance of pathogen against the currently available antimicrobial agents demands the search of new antimicrobial agents. The use of medicinal plants as natural substitute is the paramount area of research to overwhelm the drug resistance of infectious agents. Scientists have not made enough effort on the evaluation of safety of medicinal plant yet. Methods In the present study antimicrobial activity of Lawsonia inermis is investigated against clinical isolates of seven bacteria including four Gram negative (Escherichia coli, Salmonella typhi, Klebsiella spp., Shigella sonnei) and three Gram positive (Bacillus subtilis, Staphylococcus aureus, Staphylococcus epidermidis) using disc diffusion method. Four types of Lawsonia inermis extracts were prepared using methanol, chloroform, acetone and water as extraction solvents, while DMSO (Dimethyl sulfoxide) and water as dissolution solvents. The rate and extent of bacterial killing was estimated by time-kill kinetic assay at 1× MIC of each bacterial isolate. The overall safety of Lawsonia inermis extracts was assessed in mice. Results Lawsonia inermis displayed noteworthy antimicrobial activity against both gram positive and gram negative bacterial strains used in the study. The minimum value of MIC for different bacterial strains ranged from 2.31 mg/ml to 9.27 mg/ml. At 1x MIC of each bacterial isolate, 3log10 decrease in CFU was recorded after 6 hours of drug exposure and no growth was observed in almost all tested bacteria after 24 hours of exposure. No sign of toxidrome were observed during in vivo toxicity evaluation in mice at 300 mg/kg concentration. Conclusion In conclusion, the present study provides the scientific rational for medicinal use of Lawsonia inermis. The use of Lawsonia inermis extracts is of great significance as substitute antimicrobial agent in therapeutics. PMID:24289297

Chromatographic Characterization and GC-MS Evaluation of the Bioactive Constituents with Antimicrobial Potential from the Pigmented Ink of Loligo duvauceli

PubMed Central

Girija, Smiline; Duraipandiyan, Veeramuthu; Kuppusamy, Pandi Suba; Gajendran, Hariprasad; Rajagopal, Raghuraman

2014-01-01

Chromatographic characterization and the GC-MS evaluation of the black pigmented ink of Loligo duvauceli in the present study have yielded an array of bioactive compounds with potent antimicrobial property. Facing an alarm of antimicrobial resistance globally, a need for elucidating antimicrobial agents from natural sources will be the need for the hour. In this view, this study is aimed at characterizing the black pigmented ink of the Indian squid L. duvauceli. The squid ink was subjected to crude solvent extraction and was fractionated by silica gel column chromatography. TLC and HPTLC profiles were recorded. Antimicrobial bioassay of the squid ink fractions was done by agar well diffusion method. The antimicrobial fraction was then characterized using GC-MS analysis. The results showed that the n-hexane extract upon column fractionation yielded a total of 8 fractions with the mobile phase of Hex/EtOAc in different gradients. TLC and HPTLC profiles showed a single spot with a retention factor of 0.76. Fraction 1 showed significant antibacterial activity against Escherichia coli, Klebsiella pneumoniae, Staphylococcus aureus, and Lactobacillus acidophilus and a promising antifungal activity against Candida albicans. The antimicrobial fraction upon GC-MS analysis of bis(2-ethylhexyl) phthalate (BEHP) possesses the highest percentage of area normalisation (91%) with other few minor constituents. The study is concluded by stating that the antimicrobial efficacy of the squid ink might be due to the synergistic effects of the phthalate derivative and the other minor volatile compounds analysed in the squid ink. PMID:27437466

Chromatographic Characterization and GC-MS Evaluation of the Bioactive Constituents with Antimicrobial Potential from the Pigmented Ink of Loligo duvauceli.

PubMed

Girija, Smiline; Duraipandiyan, Veeramuthu; Kuppusamy, Pandi Suba; Gajendran, Hariprasad; Rajagopal, Raghuraman

2014-01-01

Chromatographic characterization and the GC-MS evaluation of the black pigmented ink of Loligo duvauceli in the present study have yielded an array of bioactive compounds with potent antimicrobial property. Facing an alarm of antimicrobial resistance globally, a need for elucidating antimicrobial agents from natural sources will be the need for the hour. In this view, this study is aimed at characterizing the black pigmented ink of the Indian squid L. duvauceli. The squid ink was subjected to crude solvent extraction and was fractionated by silica gel column chromatography. TLC and HPTLC profiles were recorded. Antimicrobial bioassay of the squid ink fractions was done by agar well diffusion method. The antimicrobial fraction was then characterized using GC-MS analysis. The results showed that the n-hexane extract upon column fractionation yielded a total of 8 fractions with the mobile phase of Hex/EtOAc in different gradients. TLC and HPTLC profiles showed a single spot with a retention factor of 0.76. Fraction 1 showed significant antibacterial activity against Escherichia coli, Klebsiella pneumoniae, Staphylococcus aureus, and Lactobacillus acidophilus and a promising antifungal activity against Candida albicans. The antimicrobial fraction upon GC-MS analysis of bis(2-ethylhexyl) phthalate (BEHP) possesses the highest percentage of area normalisation (91%) with other few minor constituents. The study is concluded by stating that the antimicrobial efficacy of the squid ink might be due to the synergistic effects of the phthalate derivative and the other minor volatile compounds analysed in the squid ink.

The Effects of Allium sativum Extracts on Biofilm Formation and Activities of Six Pathogenic Bacteria.

PubMed

Mohsenipour, Zeinab; Hassanshahian, Mehdi

2015-08-01

Garlic is considered a rich source of many compounds, which shows antimicrobial effects. The ability of microorganisms to adhere to both biotic and abiotic surfaces and to form biofilm is responsible for a number of diseases of chronic nature, demonstrating extremely high resistance to antibiotics. Bacterial biofilms are complex communities of sessile microorganisms, embedded in an extracellular matrix and irreversibly attached to various surfaces. The present study evaluated the antimicrobial activity of Allium sativum extract against the biofilms of six pathogenic bacteria and their free-living forms. The clinical isolates in this study had not been studied in any other studies, especially in regard to biofilm disruption and inhibition of biofilm cell metabolic activity. Antimicrobial activities of A. sativum L. extracts (methanol and ethanol extracts) against planktonic forms of bacteria were determined using the disc diffusion method. The minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) values were evaluated by a macrobroth dilution technique. The anti-biofilm effects were assessed by microtiter plate method. The results showed that the A. sativum L. extract discs did not have any zone of inhibition for the tested bacteria. However, The MIC values of A. sativum L. extracts (0.078 - 2.5 mg/mL) confirmed the high ability of these extracts for inhibition of planktonic bacteria. A. sativum L. extracts were efficient to inhibit biofilm structures and the concentration of each extract had a direct relation with the inhibitory effect. Finally, it can be suggested that the extracts of this plant be applied as antimicrobial agents against these pathogens, particularly in biofilm forms.

Analgesic, antibacterial and central nervous system depressant activities of Albizia procera leaves.

PubMed

Khatoon, Mst Mahfuza; Khatun, Mst Hajera; Islam, Md Ekramul; Parvin, Mst Shahnaj

2014-04-01

To ascertain analgesic, antibacterial and central nervous system (CNS) depressant activities of ethyl acetate, dichloromethane and carbon tetrachloride fractions of methanol extract of Albizia procera (A. procera) leaves. Leaves extracts of A. procera were tested for analgesic activity by acetic acid induced and formalin test method in mice. The in vitro antibacterial activity was performed by agar well diffusion method. CNS depressant activity was evaluated by hole cross and open field tests. All the extracts at 200 mg/kg exhibited significant (P<0.01) analgesic activity in acetic acid induced and formalin tests method in mice. Analgesic activity of the ethyl acetate fraction was almost same like as standard drug indomethacin in acetic acid induced method. The CNS depressant activity of the extracts at 500 mg/kg was comparable to the positive control diazepam as determined by hole cross and open field test method. The extracts exhibited moderate antimicrobial activity against all the tested microorganisms (Staphylococcus aureus, Bacillus cereus, Pseudomonas aeruginosa, Esherichia coli, Shigella soneii, Shigella boydii) at concentration of 0.8 mg/disc. The measured diameter of zone of inhibition for the extracts was within the range of 7 to 12 mm which was less than the standard kanamycin (16-24 mm). It is concluded that all the extracts possess potential analgesic and CNS depressants activity. This study also showed that different fractions of methanol extract could be potential sources of new antimicrobial agents.

Extracellular facile biosynthesis, characterization and stability of gold nanoparticles by Bacillus licheniformis.

PubMed

Singh, Sneha; Vidyarthi, Ambarish Sharan; Nigam, Vinod Kumar; Dev, Abhimanyu

2014-02-01

The development of a reliable, eco-friendly process for synthesis of gold nanoparticles (AuNPs) has gained impetus in recent years to counter the drawbacks of chemical and physical methods. This study illustrates simple, green synthesis of AuNPs in vitro using cell lysate supernatant (CLS) of non-pathogenic bacteria and to investigate its potential antimicrobial activity. Gold nanoparticles were synthesized by the reduction of precursor AuCl4- ions using the CLS of Bacillus licheniformis at 37°C upon 24 h of incubation. The nanoparticles were characterized for their morphology, particle size, optical absorption, zeta potential, and stability. Further the antimicrobial activity was assayed using cup-plate method. The process of biosynthesis was extracellular and the gold ions were reduced to stable nanogold of average size 38 nm. However, upon storage of AuNPs for longer duration at room temperature stability was influenced in terms of increase in particle size and decrease in zeta potential with respect to as synthesized nanoparticles. SEM micrographs revealed the spherical shape of AuNPs and EDX analysis confirmed the presence of gold in the sample. Also clear zone of inhibition was observed against Bacilllus subtilis MTCC 8364, Pseudomonas aeruginosa MTCC 7925, and Escherichia coli MTCC 1698 confirming the antimicrobial activity of AuNPs. The bioprocess under study was simple and less time consuming as compared to other methods as the need for harvesting AuNPs from within the microbial cells via downstream process will be eliminated. Nanoparticles exhibited good stability even in absence of external stabilizing agents. AuNPs showed good antimicrobial activity against several Gram-negative and Gram-positive pathogenic bacteria. The extracellular biosynthesis from CLS may serve as a suitable alternative for large scale synthesis of gold nanoparticles in vitro. The synthesis from lysed bacterial cell strongly suggests that exposure of microbial whole cells to the gold solution for nanoparticle formation is not necessary and that microorganism even in lysed state retained its bioreduction potential. Further the potential of biologically synthesized AuNPs as antimicrobial agents will be of great commercial importance.

Antimicrobial properties of cultivable bacteria associated with seaweeds in the Gulf of Mannar on the southeast coast of India.

PubMed

Thilakan, B; Chakraborty, K; Chakraborty, R D

2016-08-01

In this study, 234 bacterial strains were isolated from 7 seaweed species in the Gulf of Mannar on the southeast coast of India. The strains having consistent antimicrobial activity were chosen for further studies, and this constituted about 9.8% of the active strains isolated. Phylogenetic analysis using 16S rDNA sequencing with the help of classical biochemical identification indicated the existence of 2 major phyla, Firmicutes and Proteobacteria. Antimicrobial activity analysis combined with the results of amplifying genes encoding for polyketide synthetase and nonribosomal peptide synthetase showed that seaweed-associated bacteria had broad-spectrum antimicrobial activity. These epibionts might be beneficial to seaweeds by limiting or preventing the development of competing or fouling bacteria. Phylogenetic analysis of ketosynthase (KS) regions with respect to the diverse range of KS domains showed that the KS domains from the candidate isolates were of Type I. The bacterial cultures retained their antimicrobial activities after plasmid curing, which further suggested that the antimicrobial activity of these isolates was not encoded by plasmid, and the genes encoding the antimicrobial product might be present within the genome. Seaweed-associated bacteria with potential antimicrobial activity suggested that the seaweed species are an ideal ecological niche harboring specific bacterial diversity representing a largely underexplored source of antimicrobial secondary metabolites.

Food Antimicrobials Nanocarriers

PubMed Central

Blanco-Padilla, Adriana; Soto, Karen M.; Hernández Iturriaga, Montserrat

2014-01-01

Natural food antimicrobials are bioactive compounds that inhibit the growth of microorganisms involved in food spoilage or food-borne illness. However, stability issues result in degradation and loss of antimicrobial activity. Nanoencapsulation allows protection of antimicrobial food agents from unfavorable environmental conditions and incompatibilities. Encapsulation of food antimicrobials control delivery increasing the concentration of the antimicrobials in specific areas and the improvement of passive cellular absorption mechanisms resulted in higher antimicrobial activity. This paper reviews the present state of the art of the nanostructures used as food antimicrobial carriers including nanoemulsions, nanoliposomes, nanoparticles, and nanofibers. PMID:24995363

Antimicrobial potential of Dialium guineense (Wild.) stem bark on some clinical isolates in Nigeria.

PubMed

Olajubu, Fa; Akpan, I; Ojo, DA; Oluwalana, Sa

2012-01-01

The persistent increase in the number of antibiotic-resistant strains of microorganisms has led to the development of more potent but also more expensive antibiotics. In most developing countries of the world these antibiotics are not readily affordable, thus making compliance difficult. This calls for research into alternative sources of antimicrobials. Dialium guineense is a shrub of the family Leguminosae. Its stem bark is used for the treatment of cough, toothache, and bronchitis. Despite the acclaimed efficacy of D guineense, there is no scientific evidence in its support. This work was carried out to assess the antimicrobial activity of D guineense in vitro against some clinical isolates. D guineense stem bark was collected and 50 gm of air-dried and powdered stem bark of the plant was soaked for 72 hours in 1 l of each of the six solvents used in this study. Each mixture was refluxed, agitated at 200 rpm for 1 hour, filtered using Whatman No. 1 filter paper and, finally, freeze dried. The extracts were then tested for antimicrobial activity using the agar diffusion method. The highest percentage yield of 23.2% was obtained with ethanol. Phytochemical screening showed that D guineense contains anthraquinone, alkaloids, flavonoids, tannins, and saponins. The antimicrobial activity of the extracts revealed a broad spectrum of activity, with Salmonella typhi and Staphylococcus aureusa showing the greatest zones of inhibition (18.0 mm). Only Candida albicans among the fungi tested was inhibited by the extract. The greatest zone of inhibition among the fractions was 16.0 mm. D guineense exhibited bactericidal activity at the 7th and 9th hours against Streptococcus pneumoniae and S. aureus 25923 while the 10th hour against S. typhi and C. albicans. The greatest activity was noted against S pneumoniae, where there was reduced viable cell count after 6 hours of exposure. Stem bark extract of D guineense (Wild.) has the potential to be developed into an antimicrobial agent.

'Honey ointment': a natural remedy of skin wound infections.

PubMed

Tasleem, Samiyah; Naqvi, Syed Baqir Shyum; Khan, Saadat Ali; Hashimi, Khursheed

2011-01-01

Honey is a gift of nature, principally identified and valued to possess antimicrobial and anti-inflammatory activity and has been used as a natural remedy of wounds since ancient times. The objectives of this study were to evaluate the antimicrobial activity of honey against micro-organisms, to formulate a honey ointment and to evaluate the efficacy of such ointment by conducting clinical trials on skin wound infection. This experimental study was conducted at Department of Pharmaceutics, Faculty of Pharmacy, University of Karachi and Out-patient Department of Dermatology, Fauji Foundation Hospital, Rawalpindi from November 2009 to October 2010. The antimicrobial activity of Pakistani floral sources (Trachysperm copticum, Acacia nilotica species indica, Zizyphus) honey samples was investigated by disc diffusion method against freshly isolated wound infecting bacteria (Staphylococci aureus, Staphylococci epidermidis, Streptococcus faecalis, Pseudomonas aeruginosa, Klebsiella pneumonia, Escherichia coli, Proteus vulgaris and Candida albicans), and Staphylococci aureus ATCC 6538, Pseudomonas aeruginosa ATCC 9022, Escherichia coli ATCC 25922, Candida albican ATCC 15146. An ointment containing 20% active antimicrobial honey was formulated. The efficacy of such ointment was evaluated by passing thought clinical trials. A total number of 27 patients (23 skin wound infection, and 4 diabetic foot ulcer) were involved in the study. Thin layer of newly formulated honey ointment on gauze were applied two to three times per day till complete healing. In microbiological assay the honey samples were found to exhibit a very promising antimicrobial activity against all the micro-organisms tested. In clinical trial very significant results (99.15%) healing was observed in skin wound infections cases with mean healing time of 5.86 (2-20) days, and 95% diabetic foot ulcers healed with the mean healing time of 20 (8-40) days. Newly formulated ointment containing 20% active antimicrobial honey is very effective and alternative low-cost product for the treatment of wound infections.

Antibacterial and Antifungal Activity of Holothuria leucospilota Isolated From Persian Gulf and Oman Sea

PubMed Central

Adibpour, Neda; Nasr, Farhad; Nematpour, Fatemeh; Shakouri, Arash; Ameri, Abdolghani

2014-01-01

Background: Emergence of antimicrobial resistance toward a number of conventional antibiotics has triggered the search for antimicrobial agents from a variety of sources including the marine environment. Objectives: The aim of this study was to evaluate the antimicrobial potential of Holothuria leucospilota from Qeshm and Kharg Islands against some selected bacteria and fungi. Materials and Methods: In this investigation, sea cucumbers from two coastal cities of Persian Gulf were collected in March and May 2011 and identified by the scale method according to the food and agriculture organization of the United Nations. Antibacterial activity of hydroalcoholic extracts of the body wall, cuvierian organs and coelomic fluid, methanol, chloroform, and n-hexane extracts of the body wall were evaluated by the spot test. In addition, their antifungal activity was assessed by the broth dilution method. Results: The displayed effect was microbiostatic at concentrations of 1000 and 2000 µg/mL rather than microbicidal. The highest activity of hydroalcoholic extracts was exhibited by body wall, cuvierian organs and coelomic fluid against Escherichia coli, Salmonella typhi, Staphylococcus aureus and Pseudomonas aeruginosa; Aspergillus niger, A. fumigatus, A. flavus and A. brasilensis. However, none of the methanol, chloroform and n-haxane extracts showed appreciable effects against Shigella dysenteriae, Proteus vulgaris, Bacillus cereus, S. epidermidis and Candida albicans. Moreover, cuvierian organs did not possess any antifungal potential. Conclusions: Our data indicated that water-methanol extracts from the body wall of H. leucospilota possess antibacterial and antifungal activity. However, additional and in-depth studies are required to isolate and identify the active component(s). PMID:25147657

Antioxidant and antimicrobial activities of clove bud essential oil and eugenol nanoparticles in alcohol-free microemulsion.

PubMed

Hamed, Said Fatouh; Sadek, Zainab; Edris, Amr

2012-01-01

Clove bud essential oil (CEO) and its major individual phenolic constituent eugenol were formulated as nanoparticles in water-based microemulsion systems. The oil titration method was used to incorporate different amounts of the oil and eugenol in the micellar solution of Tween-20. The Antioxidant and antimicrobial activities were evaluated using the DPPH* free radical scavenging assay and the agar disc dilution method, respectively. Results showed that microemulsion improved the evaluated activities of CEO and eugenol compared with the crude counterparts. Individual eugenol microemulsion was more effective than CEO microemulsion which contained only 61.7% eugenol among its constituents. The results of this study could have potential applications in water-based disinfectants, preservation and flavoring of food and in personal hygiene products. It may also have promising applications in the nutraceutical and functional beverage field.

Durability of Anti-Infective Effect of Long-Term Silicone Sheath Catheters Impregnated with Antimicrobial Agents

PubMed Central

Tcholakian, Robert K.; Raad, Issam I.

2001-01-01

This study was performed to test the long-term antimicrobial efficacy of impregnated silicone catheters comprising an antimicrobial layer sandwiched between an external surface sheath and a luminal surface silicone sheath. The design of the catheter permits the introduction of various antimicrobials in addition to anticoagulants or antifibrins in the antimicrobial layer and allows their gradual release over a period of months after insertion. The in vitro data presented show that the catheter can provide antimicrobial activity for 90 days, after being replated for 15 7-day cycles of replating. When the catheters were immersed in human serum and incubated at 37°C, they demonstrated significant antimicrobial activity after more than 325 days of incubation. The significant long-term in vitro antimicrobial activity observed may imply effective in vivo activity for almost 1 year after insertion and could serve as a cost-effective alternative to surgically implantable silicone catheters. PMID:11408213

Model Analytical Development for Physical, Chemical, and Biological Characterization of Momordica charantia Vegetable Drug

PubMed Central

Guimarães, Geovani Pereira; Santos, Ravely Lucena; Júnior, Fernando José de Lima Ramos; da Silva, Karla Monik Alves; de Souza, Fabio Santos

2016-01-01

Momordica charantia is a species cultivated throughout the world and widely used in folk medicine, and its medicinal benefits are well documented, especially its pharmacological properties, including antimicrobial activities. Analytical methods have been used to aid in the characterization of compounds derived from plant drug extracts and their products. This paper developed a methodological model to evaluate the integrity of the vegetable drug M. charantia in different particle sizes, using different analytical methods. M. charantia was collected in the semiarid region of Paraíba, Brazil. The herbal medicine raw material derived from the leaves and fruits in different particle sizes was analyzed using thermoanalytical techniques as thermogravimetry (TG) and differential thermal analysis (DTA), pyrolysis coupled to gas chromatography/mass spectrometry (PYR-GC/MS), and nuclear magnetic resonance (1H NMR), in addition to the determination of antimicrobial activity. The different particle surface area among the samples was differentiated by the techniques. DTA and TG were used for assessing thermal and kinetic parameters and PYR-GC/MS was used for degradation products chromatographic identification through the pyrograms. The infusions obtained from the fruit and leaves of Momordica charantia presented antimicrobial activity. PMID:27579215

Chemical composition and antimicrobial activity of essential oil from cones of Pinus koraiensis.

PubMed

Lee, Jeong-Ho; Yang, Hye-Young; Lee, Hong-Sub; Hong, Soon-Kwang

2008-03-01

The essential oil from the cones of Pinus koraiensis was prepared after removing the seeds, and its chemical composition analyzed using gas chromatography-mass spectrometry (GC-MS). Hydrodistillation of the P. koraiensis cones yielded 1.07% (v/w) of essential oil, which was almost three times the amount of essential oil extracted from the needles of the same plant. Moreover, the antimicrobial activities of the oil against the growth of Gram-positive bacteria, Gram-negative bacteria, and fungi were evaluated using the agar disc diffusion method and broth microdilution method. Eighty-seven components, comprising about 96.8% of the total oil, were identified. The most abundant oil components were limonene (27.90%), alpha-pinene (23.89%), beta-pinene (12.02%), 3-carene (4.95%), beta-myrcene (4.53%), isolongifolene (3.35%), (-)-bornyl acetate (2.02%), caryophyllene (1.71%), and camphene (1.54%). The essential oil was confirmed to have significant antimicrobial activities, especially against pathogenic fungal strains such as Candida glabrata YFCC 062 and Cryptococcus neoformans B 42419. Therefore, the present results indicate that the essential oil from the cones of Pinus koraiensis can be used in various ways as a nontoxic and environmentally friendly disinfectant.

Antimicrobial activity of antihypertensive food-derived peptides and selected alanine analogues.

PubMed

McClean, Stephen; Beggs, Louise B; Welch, Robert W

2014-03-01

This study evaluated four food-derived peptides with known antihypertensive activities for antimicrobial activity against pathogenic microorganisms, and assessed structure-function relationships using alanine analogues. The peptides (EVSLNSGYY, barley; PGTAVFK, soybean; TTMPLW, α-casein; VHLPP, α-zein) and the six alanine substitution peptides of PGTAVFK were synthesised, characterised and evaluated for antimicrobial activity using the bacteria, Escherichia coli, Staphylococcus aureus, and Micrococcus luteus and the yeast, Candida albicans. The peptides TTMPLW and PGTAVFK inhibited growth of all four microorganisms tested, with activities of a similar order of magnitude to ampicillin and ethanol controls. EVSLNSGYY inhibited the growth of the bacteria, but VHLPP showed no antimicrobial activity. The alanine analogue, PGAAVFK showed the highest overall antimicrobial activity and PGTAVFA showed no activity; overall, the activities of the analogues were consistent with their structures. Some peptides with antihypertensive activity also show antimicrobial activity, suggesting that food-derived peptides may exert beneficial effects via a number of mechanisms. Copyright © 2013 Elsevier Ltd. All rights reserved.

Biosynthesis of silver nanoparticles using Alternanthera sessilis (Linn.) extract and their antimicrobial, antioxidant activities.

PubMed

Niraimathi, K L; Sudha, V; Lavanya, R; Brindha, P

2013-02-01

The present work focuses the use of the aqueous extract of Alternanthera sessilis Linn. (Amaranthaceae) in producing silver nanoparticles (AgNPs) from silver nitrate aqueous. Phytochemical analysis of the extract revealed the presence of alkaloid, tannins, ascorbic acid, carbohydrates and proteins and they serve as effective reducing and capping agents for converting silver nitrate into nanoparticles. The synthesized silver nanoparticles (AgNPs) were also tested for proteins and ascorbic acid. Its pH was also determined (5.63). The AgNPs obtained was characterized by UV-vis spectroscopy, FT-IR spectroscopy, SEM, Zeta sizer and TG-DSC. SEM images which revealed the presence of various shapes and sizes. FT-IR spectrum showed the AgNPs having a coating of proteins indicating a dual role of bio-molecules responsible for capping and efficient stabilization of the silver nanoparticles. Presence of impurities and melting point profile were screened by TG-DSC analyzer. AgNPs were synthesized from the silver nitrate through the reducing power of ascorbic acid present in A. sessilis leaves. In this study, we also investigated antimicrobial and antioxidant activity of green synthesized AgNPs. The antimicrobial activity is investigated by Bauer et al.'s method. Antioxidant activity was done by DPPH method. Copyright © 2012 Elsevier B.V. All rights reserved.

Potential Adverse Effects of Broad-Spectrum Antimicrobial Exposure in the Intensive Care Unit

PubMed Central

Wiens, Jenna; Finlayson, Samuel; Mahoney, Monica V; Celi, Leo Anthony

2018-01-01

Abstract Background The potential adverse effects of empiric broad-spectrum antimicrobial use among patients with suspected but subsequently excluded infection have not been fully characterized. We sought novel methods to quantify the risk of adverse effects of broad-spectrum antimicrobial exposure among patients admitted to an intensive care unit (ICU). Methods Among all adult patients admitted to ICUs at a single institution, we selected patients with negative blood cultures who also received ≥1 broad-spectrum antimicrobials. Broad-spectrum antimicrobials were categorized in ≥1 of 5 categories based on their spectrum of activity against potential pathogens. We performed, in serial, 5 cohort studies to measure the effect of each broad-spectrum category on patient outcomes. Exposed patients were defined as those receiving a specific category of broad-spectrum antimicrobial; nonexposed were all other patients in the cohort. The primary outcome was 30-day mortality. Secondary outcomes included length of hospital and ICU stay and nosocomial acquisition of antimicrobial-resistant bacteria (ARB) or Clostridium difficile within 30 days of admission. Results Among the study cohort of 1918 patients, 316 (16.5%) died within 30 days, 821 (42.8%) had either a length of hospital stay >7 days or an ICU length of stay >3 days, and 106 (5.5%) acquired either a nosocomial ARB or C. difficile. The short-term use of broad-spectrum antimicrobials in any of the defined broad-spectrum categories was not significantly associated with either primary or secondary outcomes. Conclusions The prompt and brief empiric use of defined categories of broad-spectrum antimicrobials could not be associated with additional patient harm. PMID:29479546

In vitro antibacterial and antifungal activities of Cassia fistula Linn. fruit pulp extracts

PubMed Central

Bhalodia, N. R.; Nariya, P. B.; Acharya, R. N.; Shukla, V. J.

2012-01-01

Aim of the study is to assess the antimicrobial activity Cassia fistula fruit pulp extracts on some bacterial and fungal strains. Hydro alcohol and chloroform extracts of Cassia fistula fruit pulp were evaluated for the potential antimicrobial activity. The antimicrobial activity was determined in both the extracts using the agar disc diffusion method. Extracts were effective on tested microorganisms. The antibacterial and antifungal activities of solvent extracts (5, 25, 50, 100, 250 μg/mL) of C. fistula were tested against two gram positive, two gram negative human pathogenic bacteria and three fungi, respectively. Crude extracts of C. fistula exhibited moderate to strong activity against most of the bacteria tested. The tested bacterial strains were Staphylococcus aureus, Streptococcus pyogenes, Escherichia coil, Pseudomonas aeruginosa, and fungal strains were Aspergillus. niger, Aspergillus. clavatus, Candida albicans. The antibacterial potential of the extracts were found to be dose dependent. The antibacterial activities of the C. fistula were due to the presence of various secondary metabolites. Hence, these plants can be used to discover bioactive natural products that may serve as leads in the development of new pharmaceuticals research activities. PMID:23049197

A Review on Antibacterial, Antiviral, and Antifungal Activity of Curcumin

PubMed Central

Zorofchian Moghadamtousi, Soheil; Abdul Kadir, Habsah; Hassandarvish, Pouya; Tajik, Hassan; Abubakar, Sazaly; Zandi, Keivan

2014-01-01

Curcuma longa L. (Zingiberaceae family) and its polyphenolic compound curcumin have been subjected to a variety of antimicrobial investigations due to extensive traditional uses and low side effects. Antimicrobial activities for curcumin and rhizome extract of C. longa against different bacteria, viruses, fungi, and parasites have been reported. The promising results for antimicrobial activity of curcumin made it a good candidate to enhance the inhibitory effect of existing antimicrobial agents through synergism. Indeed, different investigations have been done to increase the antimicrobial activity of curcumin, including synthesis of different chemical derivatives to increase its water solubility as well ass cell up take of curcumin. This review aims to summarize previous antimicrobial studies of curcumin towards its application in the future studies as a natural antimicrobial agent. PMID:24877064

In Vitro Evaluation of Nanoscale Hydroxyapatite-Based Bone Reconstructive Materials with Antimicrobial Properties.

PubMed

Ajduković, Zorica R; Mihajilov-Krstev, Tatjana M; Ignjatović, Nenad L; Stojanović, Zoran; Mladenović-Antić, Snezana B; Kocić, Branislava D; Najman, Stevo; Petrović, Nenad D; Uskoković, Dragan P

2016-02-01

In the field of oral implantology the loss of bone tissue prevents adequate patient care, and calls for the use of synthetic biomaterials with properties that resemble natural bone. Special attention is paid to the risk of infection after the implantation of these materials. Studies have suggested that some nanocontructs containing metal ions have antimicrobial properties. The aim of this study was to examine the antimicrobial and hemolytic activity of cobalt-substituted hydroxyapatite nanoparticles, compared to hydroxyapatite and hydroxyapatite/poly-lactide-co-glycolide. The antibacterial effects of these powders were tested against two pathogenic bacterial strains: Escherichia coi (ATCC 25922) and Staphylococcus aureus (ATCC 25923), using the disc diffusion method and the quantitative antimicrobial test in a liquid medium. The quantitative antimicrobial test showed that all of the tested biomaterials have some antibacterial properties. The effects of both tests were more prominent in case of S. aureus than in E coli. A higher percentage of cobalt in the crystal structure of cobalt-substituted hydroxyapatite nanoparticles led to an increased antimicrobial activity. All of the presented biomaterial samples were found to be non-hemolytic. Having in mind that the tested of cobalt-substituted hydroxyapatite (Ca/Co-HAp) material in given concentrations shows good hemocompatibility and antimicrobial effects, along with its previously studied biological properties, the conclusion can be reached that it is a potential candidate that could substitute calcium hydroxyapatite as the material of choice for use in bone tissue engineering and clinical practices in orthopedic, oral and maxillofacial surgery.

Preventing maritime transport of pathogens: the remarkable antimicrobial properties of silver-supported catalysts for ship ballast water disinfection.

PubMed

Theologides, C P; Theofilou, S P; Anayiotos, A; Costa, C N

2017-07-01

Ship ballast water (SBW) antimicrobial treatment is considered as a priority issue for the shipping industry. The present work investigates the possibility of utilizing antimicrobial catalysis as an effective method for the treatment of SBW. Taking into account the well-known antimicrobial properties of ionic silver (Ag + ), five silver-supported catalysts (Ag/γ-Al 2 O 3 ) with various loadings (0.05, 0.1, 0.2, 0.5, and 1 wt%) were prepared and examined for the antimicrobial treatment of SBW. The bactericidal activity of the aforementioned catalysts was investigated towards the inhibition of Escherichia coli (Gram-negative) and Escherichia faecalis (Gram-positive) bacteria. Catalytic experiments were conducted in a three-phase continuous flow stirred tank reactor, used in a semi-batch mode. It was found that using the catalyst with the lowest metal loading, the inhibition of E. coli reached 95.8% after 30 minutes of treatment of an E. coli bacterial solution, while the inhibition obtained for E. faecalis was 76.2% after 60 minutes of treatment of an E. faecalis bacterial solution. Even better results (100% inhibition after 5 min of reaction) were obtained using the catalysts with higher Ag loadings. The results of the present work indicate that the prepared monometallic catalysts exert their antimicrobial activity within a short period of time, revealing, for the first time ever, that the field of antimicrobial heterogeneous catalysis using deposited ionic silver on a solid support may prove decisive for the disinfection of SBW.

[First Argentine consensus guidelines for in vitro antimicrobial susceptibility testing of clinically relevant anaerobic bacteria in humans/ Anaerobic Subcommittee of the Asociación Argentina de Microbiología].

PubMed

Legaria, María C; Bianchini, Hebe M; Castello, Liliana; Carloni, Graciela; Di Martino, Ana; Fernández Canigia, Liliana; Litterio, Mirta; Rollet, Raquel; Rossetti, Adelaida; Predari, Silvia C

2011-01-01

Through time, anaerobic bacteria have shown good susceptibility to clinically useful antianaerobic agents. Nevertheless, the antimicrobial resistance profile of most of the anaerobic species related to severe infections in humans has been modified in the last years and different kinds of resistance to the most active agents have emerged, making their effectiveness less predictable. With the aim of finding an answer and for the purpose of facilitating the detection of anaerobic antimicrobial resistance, the Anaerobic Subcommittee of the Asociación Argentina de Microbiología developed the First Argentine consensus guidelines for in vitro antimicrobial susceptibility testing of clinically relevant anaerobic bacteria in humans. This document resulted from the compatibilization of the Clinical and Laboratory Standards Institute recommendations, the international literature and the work and experience of the Subcommittee. The Consensus document provides a brief taxonomy review, and exposes why and when anaerobic antimicrobial susceptibility tests should be conducted, and which antimicrobial agents can be used according to the species involved. The recommendations on how to perform, read and interpret in vitro anaerobic antimicrobial susceptibility tests with each method are exposed. Finally, the antibiotic susceptibility profile, the classification of antibiotics according to their in vitro activities, the natural and acquired mechanisms of resistance, the emerging resistance and the regional antibiotic resistance profile of clinically relevant anaerobic species are shown.

In vivo antimicrobial activity of silver nanoparticles produced via a green chemistry synthesis using Acacia rigidula as a reducing and capping agent.

PubMed

Escárcega-González, Carlos Enrique; Garza-Cervantes, J A; Vázquez-Rodríguez, A; Montelongo-Peralta, Liliana Zulem; Treviño-González, M T; Díaz Barriga Castro, E; Saucedo-Salazar, E M; Chávez Morales, R M; Regalado Soto, D I; Treviño González, F M; Carrazco Rosales, J L; Cruz, Rocío Villalobos; Morones-Ramírez, José Rubén

2018-01-01

One of the main issues in the medical field and clinical practice is the development of novel and effective treatments against infections caused by antibiotic-resistant bacteria. One avenue that has been approached to develop effective antimicrobials is the use of silver nanoparticles (Ag-NPs), since they have been found to exhibit an efficient and wide spectrum of antimicrobial properties. Among the main drawbacks of using Ag-NPs are their potential cytotoxicity against eukaryotic cells and the latent environmental toxicity of their synthesis methods. Therefore, diverse green synthesis methods, which involve the use of environmentally friendly plant extracts as reductive and capping agents, have become attractive to synthesize Ag-NPs that exhibit antimicrobial effects against resistant bacteria at concentrations below toxicity thresholds for eukaryotic cells. In this study, we report a green one-pot synthesis method that uses Acacia rigidula extract as a reducing and capping agent, to produce Ag-NPs with applications as therapeutic agents to treat infections in vivo. The Ag-NPs were characterized using transmission electron microscopy (TEM), high-resolution TEM, selected area electron diffraction, energy-dispersive spectroscopy, ultraviolet-visible, and Fourier transform infrared. We show that Ag-NPs are spherical with a narrow size distribution. The Ag-NPs show antimicrobial activities in vitro against Gram-negative ( Escherichia coli , Pseudomonas aeruginosa , and a clinical multidrug-resistant strain of P. aeruginosa ) and Gram-positive ( Bacillus subtilis ) bacteria. Moreover, antimicrobial effects of the Ag-NPs, against a resistant P. aeruginosa clinical strain, were tested in a murine skin infection model. The results demonstrate that the Ag-NPs reported in this work are capable of eradicating pathogenic resistant bacteria in an infection in vivo. In addition, skin, liver, and kidney damage profiles were monitored in the murine infection model, and the results demonstrate that Ag-NPs can be used safely as therapeutic agents in animal models. Together, these results suggest the potential use of Ag-NPs, synthesized by green chemistry methods, as therapeutic agents against infections caused by resistant and nonresistant strains.

CHARACTERIZATION OF A NARROW SPECTRUM ANTIMICROBIAL THAT EXHIBITS SPECIFIC ACTIVITY AGAINST UROPATHOGENIC BACTERIA

DTIC Science & Technology

2017-08-28

NARROW-SPECTRUM ANTIMICROBIAL THAT EXHIBITS SPECIFIC ACTIVITY AGAINST UROPATHOGENIC BACTERIA by Caitlin M. Barrows Courtney M. Cowell Jennifer...From - To) October 2015 – September 2016 4. TITLE AND SUBTITLE CHARACTERIZATION OF A NARROW-SPECTRUM ANTIMICROBIAL THAT EXHIBITS SPECIFIC ACTIVITY ...objective of the work described in this report is to identify a narrow-spectrum antimicrobial that exhibits targeted activity against uropathogenic

Chitosan-Iron Oxide Coated Graphene Oxide Nanocomposite Hydrogel: A Robust and Soft Antimicrobial Biofilm.

PubMed

Konwar, Achyut; Kalita, Sanjeeb; Kotoky, Jibon; Chowdhury, Devasish

2016-08-17

We report a robust biofilm with antimicrobial properties fabricated from chitosan-iron oxide coated graphene oxide nanocomposite hydrogel. For the first time, the coprecipitation method was used for the successful synthesis of iron oxide coated graphene oxide (GIO) nanomaterial. After this, films were fabricated by the gel-casting technique aided by the self-healing ability of the chitosan hydrogel network system. Both the nanomaterial and the nanocomposite films were characterized by techniques such as scanning electron microscopy, FT-IR spectroscopy, X-ray diffraction, and vibrating sample magnetometry. Measurements of the thermodynamic stability and mechanical properties of the films indictaed a significant improvement in their thermal and mechanical properties. Moreover, the stress-strain profile indicated the tough nature of the nanocomposite hydrogel films. These improvements, therefore, indicated an effective interaction and good compatibility of the GIO nanomaterial with the chitosan hydrogel matrix. In addition, it was also possible to fabricate films with tunable surface properties such as hydrophobicity simply by varying the loading percentage of GIO nanomaterial in the hydrogel matrix. Fascinatingly, the chitosan-iron oxide coated graphene oxide nanocomposite hydrogel films displayed significant antimicrobial activities against both Gram-positive and Gram-negative bacterial strains, such as methicillin-resistant Staphylococcus aureus, Staphylococcus aureus, and Escherichia coli, and also against the opportunistic dermatophyte Candida albicans. The antimicrobial activities of the films were tested by agar diffusion assay and antimicrobial testing based on direct contact. A comparison of the antimicrobial activity of the chitosan-GIO nanocomposite hydrogel films with those of individual chitosan-graphene oxide and chitosan-iron oxide nanocomposite films demonstrated a higher antimicrobial activity for the former in both types of tests. In vitro hemolysis potentiality tests and MTT assays of the nanocomposite films indicated a noncytotoxic nature of the films, which conveyed the possibility of potential applications of these soft and tough films in biomedical as well as in the food industry.

Use of Lactobacillus plantarum Strains as a Bio-Control Strategy against Food-Borne Pathogenic Microorganisms

PubMed Central

Arena, Mattia Pia; Silvain, Amandine; Normanno, Giovanni; Grieco, Francesco; Drider, Djamel; Spano, Giuseppe; Fiocco, Daniela

2016-01-01

Lactobacillus plantarum is one of the most versatile species extensively used in the food industry both as microbial starters and probiotic microorganisms. Several L. plantarum strains have been shown to produce different antimicrobial compounds such as organic acids, hydrogen peroxide, diacetyl, and also bacteriocins and antimicrobial peptides, both denoted by a variable spectrum of action. In recent decades, the selection of microbial molecules and/or bacterial strains able to produce antagonistic molecules to be used as antimicrobials and preservatives has been attracting scientific interest, in order to eliminate or reduce chemical additives, because of the growing attention of consumers for healthy and natural food products. The aim of this work was to investigate the antimicrobial activity of several food-isolated L. plantarum strains, analyzed against the pathogenic bacteria Listeria monocytogenes, Salmonella Enteritidis, Escherichia coli O157:H7 and Staphylococcus aureus. Antagonistic activity was assayed by agar spot test and revealed that strain L. plantarum 105 had the strongest ability to contrast the growth of L. monocytogenes, while strains L. plantarum 106 and 107 were the most active microorganisms against E. coli O157:H7. The antimicrobial ability was also screened by well diffusion assay and broth micro-dilution method using cell-free supernatants (CFS) from each Lactobacillus strain. Moreover, the chemical nature of the molecules released in the CFS, and possibly underlying the antagonistic activity, was preliminary characterized by exposure to different constraints such as pH neutralization, heating, catalase, and proteinase treatments. Our data suggest that the ability of L. plantarum cultures to contrast pathogens growth in vitro depends, at least in part, on a pH-lowering effect of supernatants and/or on the presence of organic acids. Cluster analysis was performed in order to group L. plantarum strains according to their antimicrobial effect. This study emphasizes the tempting use of the tested L. plantarum strains and/or their CFS as antimicrobial agents against food-borne pathogens. PMID:27148172

The assessment of the antibacterial and antifungal activities of aspirin, EDTA and aspirin-EDTA combination and their effectiveness as antibiofilm agents.

PubMed

Al-Bakri, A G; Othman, G; Bustanji, Y

2009-07-01

To evaluate the antimicrobial activities of aspirin, EDTA and an aspirin-EDTA (A-EDTA) combination against Pseudomonas aeruginosa, Escherichia coli and Candida albicans in planktonic and biofilm cultures. Minimal inhibitory concentrations (MIC) and minimal biocidal concentrations (MBC) were determined using twofold broth microdilution and viable counting methods, respectively. Aspirin's recorded MIC values ranged from 1.2 to 2.7 mg ml(-1). Checkerboard assay demonstrated a synergism in antimicrobial activity upon combination. Aspirin's minimal biofilm eradication concentration values (MBEC) against the established biofilms ranged between 1.35 and 3.83 mg ml(-1). A complete eradication of bacterial biofilms was achieved after a 4-h treatment with the A-EDTA combination. Both aspirin and EDTA possess broad-spectrum antimicrobial activity for both planktonic and biofilm cultures. Aspirin used at the MBEC for 24 h was successful in eradicating P. aeruginosa, E. coli and C. albicans biofilms established on abiotic surfaces. Moreover, the exposure to the A-EDTA combination (4 h) effected complete bacterial biofilm eradication. There is a continuous need for the discovery of new antimicrobial agents. Aspirin and EDTA are 'nonantibiotic drugs', the combination of which can be used successfully to treat and eradicate biofilms established on abiotic surfaces.

Antibacterial activity and composition of essential oils from Pelargonium graveolens L'Her and Vitex agnus-castus L.

PubMed

Ghannadi, A; Bagherinejad, Mr; Abedi, D; Jalali, M; Absalan, B; Sadeghi, N

2012-12-01

Essential oils are volatile compounds that have been used since Middle Ages as antimicrobial, anti-inflammatory, sedative, local anesthetic and food flavoring agents. In the current study, essential oils of Pelargonium graveolens L'Her and Vitex agnus-castus L. were analyzed for their antibacterial activities. The chemical compositions of essential oils were characterized by GC-MS. Disc diffusion method was used to study antimicrobial activity. Inhibition zones showed that the essential oils of the two plants were active against all of the studied bacteria (except Listeria monocytogenes). The susceptibility of the strains changed with the dilution of essential oils in DMSO. The pure essential oils showed the most extensive inhibition zones and they were very effective antimicrobial compounds compared to chloramphenicol and amoxicillin. The most susceptible strain against these two essential oils was Staphylococcus aureus. It seems that β-citronellol is a prominent part of P. graveolens volatile oil and caryophyllene oxide is a famous and important part of V. agnus-castus volatile oil and their probable synergistic effect with other constituents are responsible for the antibacterial effects of these oils. However further studies must be performed to confirm the safety of these oils for use as antimicrobial agents and natural preservatives in different products.

Antimicrobial Activity of a Neem Cake Extract in a Broth Model Meat System

PubMed Central

Del Serrone, Paola; Nicoletti, Marcello

2013-01-01

This work reports on the antimicrobial activity of an ethyl acetate extract of neem (Azadirachta indica) cake (NCE) against bacteria affecting the quality of retail fresh meat in a broth model meat system. NCE (100 µg) was also tested by the agar disc diffusion method. It inhibited the growth of all tested microorganisms. The NCE growth inhibition zone (IZ) ranged 11.33–22.67 mm while the ciprofloxacin (10 µg) IZ ranged from 23.41–32.67 mm. There was no significant difference (p ≤ 0.05) between the antimicrobial activity of NCE and ciprofloxacin vs. C. jejuni and Leuconostoc spp. The NCE antibacterial activity was moreover determined at lower concentrations (1:10–1:100,000) in micro-assays. The percent growth reduction ranged from 61 ± 2.08–92 ± 3.21. The higher bacterial growth reduction was obtained at 10 µg concentration of NCE. Species-specific PCR and multiplex PCR with the DNA dye propidium monoazide were used to directly detect viable bacterial cells from experimentally contaminated meat samples. The numbers of bacterial cells never significantly (p ≤ 0.05) exceeded the inocula concentration used to experimentally contaminate the NCE treated meat. This report represents a screening methodology to evaluate the antimicrobial capability of a herbal extract to preserve meat. PMID:23917814

Antitumor and antimicrobial activities of endophytic fungi from medicinal parts of Aquilaria sinensis.

PubMed

Cui, Jin-long; Guo, Shun-xing; Xiao, Pei-gen

2011-05-01

The purpose of this study was to isolate and characterize endophytic fungi from the stem tissue which can produce fragrant ingredients in Aquilaria sinensis (also called agarwood) to determine their antitumor and antimicrobial activities. Twenty-eight fungal endophytes were isolated from agarwood by strict sterile sample preparation and were classified into 14 genera and 4 taxonomic classes (Sordariomycetes, Dothideomycetes, Saccharomycetes, and Zygomycetes) based on molecular identification. Of the 28 isolates, 13 (46.4%) showed antimicrobial activity against at least one of the test strains by the agar well diffusion method, and 23 isolates (82.1%) displayed antitumor activity against at least one of five cancer cell lines by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The diameters of inhibition zones of YNAS07, YNAS14, HNAS04, HNAS05, HNAS08, and HNAS11 were equal to or higher than 14.0 mm against Staphylococcus aureus, Escherichia coli, Bacillus subtilis, B. subtilis, Aspergillus fumigatus, and B. subtilis, respectively. The inhibition rates of YNAS06, YNAS08, and HNAS06 were not less than 60% to 293-T, 293-T, and SKVO3 cells, respectively. These results suggest that the endophytic fungi associated with agarwood will provide us with not only useful micro-ecological information, but also potential antimicrobial and antitumor agents.

Recombinant production of a chimeric antimicrobial peptide in E. coli and assessment of its activity against some avian clinically isolated pathogens.

PubMed

Tanhaiean, Abass; Azghandi, Marjan; Razmyar, Jamshid; Mohammadi, Elyas; Sekhavati, Mohammad Hadi

2018-06-08

Over the last decades, poultry industry faced to the rapid emergence of multidrug-resistant bacteria as a global concern. Antimicrobial peptide (AMPs) known as potential antibiotic alternative and were considered as a new antimicrobial agent. Current methods of production and purification of AMPs have several limitations such as: costly, time-consuming and killing the producing host cells in recombinant form. In the present study, a chimeric peptide derived from camel lactoferrin was produced in Escherichia coli periplasmic space using a pET-based expression system and its antibacterial activity was determined on some avian pathogens in vitro. A carboxy-terminal polyhistidine tag was used for purification by Ni 2+ affinity chromatography with an average yield of 0.42 g/L. The His-tagged chimeric peptide showed different range of antimicrobial activity against clinically isolated avian pathogens with low chicken blood hemolysis activity and high serum stability. Overall, the results of this investigation showed the recombinant chimeric peptide was successfully expressed in pET-based expression system and could be considered as a proper alternative for some currently used antibiotics in poultry industry and drugs veterinary medicine. Copyright © 2018 Elsevier Ltd. All rights reserved.

Antimicrobial activity of five essential oils against origin strains of the Enterobacteriaceae family.

PubMed

Peñalver, Pedro; Huerta, Belén; Borge, Carmen; Astorga, Rafael; Romero, Rafael; Perea, Anselmo

2005-01-01

An in vitro assay measuring the antimicrobial activity of essential oils of Coridothymus capitatus (Spanish origanum), Satureja montana, Thymus mastichina (Spanish Origanum majorana), Thymus zygis (Spanish variety of Thymus vulgaris) and Origanum vulgare has been carried out against poultry origin strains of Escherichia coli, Salmonella enteritidis and Salmonella essen, and pig origin strains of enterotoxigenic E. coli (ETEC), Salmonella choleraesuis and Salmonella typhimurium. Using the broth microdilution method, all the essential oils showed an MIC > or = 2% (v/v) for the two strains of E. coli. The essential oil that showed the highest antimicrobial activity against the four strains of Salmonella was Origanum vulgare (MIC < or = 1% v/v), followed by Thymus zygis (MIC < or =2% v/v). Thymus mastichina inhibited all the microorganisms at the highest concentration, 4% (v/v), while the rest of the essential oils showed highly variable results. By chemotyping, higher inhibitory capacity was observed in the oils with a higher percentage of phenolic components (carvacrol and thymol) in comparison with oils containing the monoterpenic alcohol linalool. The results of this work confirm the antimicrobial activity of some essential oils, as well as their potential application in the treatment and prevention of poultry and pig diseases caused by salmonella.

Selection of enhanced antimicrobial activity posing lactic acid bacteria characterised by (GTG)5-PCR fingerprinting.

PubMed

Šalomskienė, Joana; Abraitienė, Asta; Jonkuvienė, Dovilė; Mačionienė, Irena; Repečkienė, Jūratė

2015-07-01

The aim of the study was a detail evaluation of genetic diversity among the lactic acid bacteria (LAB) strains having an advantage of a starter culture in order to select genotypically diverse strains with enhanced antimicrobial effect on some harmfull and pathogenic microorganisms. Antimicrobial activity of LAB was performed by the agar well diffusion method and was examined against the reference strains and foodborne isolates of Bacillus cereus, Listeria monocytogenes, Escherichia coli, Staphylococcus aureus and Salmonella Typhimurium. Antifungal activity was tested against the foodborne isolates of Candida parapsilosis, Debaromyces hansenii, Kluyveromyces marxianus, Pichia guilliermondii, Yarowia lipolytica, Aspergillus brasiliensis, Aspergillus versicolor, Cladosporium herbarum, Penicillium chrysogenum and Scopulariopsis brevicaulis. A total 40 LAB strains representing Lactobacillus (23 strains), Lactococcus (13 strains) and Streptococcus spp. (4 strains) were characterised by repetitive sequence based polymerase chain reaction fingerprinting which generated highly discriminatory profiles, confirmed the identity and revealed high genotypic heterogeneity among the strains. Many of tested LAB demonstrated strong antimicrobial activity specialised against one or few indicator strains. Twelve LAB strains were superior in suppressing growth of the whole complex of pathogenic bacteria and fungi. These results demonstrated that separate taxonomic units offered different possibilities of selection for novel LAB strains could be used as starter cultures enhancing food preservation.

Evaluation of the Interaction between the Poincianella pyramidalis (Tul.) LP Queiroz Extract and Antimicrobials Using Biological and Analytical Models.

PubMed

Chaves, Thiago P; Fernandes, Felipe Hugo A; Santana, Cleildo P; Santos, Jocimar S; Medeiros, Francinalva D; Felismino, Délcio C; Santos, Vanda L; Catão, Raïssa Mayer R; Coutinho, Henrique Douglas M; Medeiros, Ana Cláudia D

2016-01-01

Poincianella pyramidalis (Tul.) LP Queiroz (Fabaceae) is an endemic tree of northeastern Brazil, occurring mainly in the Caatinga. Its medicinal use is widespread and is an important therapeutic option against diarrhea, dysentery, and respiratory and urinary infections, among other diseases. In this study we determined the chemical marker and evaluated the interaction between P. pyramidalis extract and a commercial antimicrobial through the use of biological and analytical models. To obtain the extract, an ethanol-water mixture (50:50 v/v) was used as solvent. It was nebulized in a spray dryer using colloidal silicon dioxide as a drying adjuvant. The extract (ENPp) was subjected to HPLC analysis to verify the presence of certain secondary metabolites. The Minimum Inhibitory Concentration (MIC) of the extract against Gram-negative bacteria was determined by broth microdilution and the MIC of synthetic antimicrobial drugs in the presence and absence of the extract. The antioxidant activity of ENPp was evaluated by the DPPH method. The compatibility between the antimicrobial and the extract was evaluated by thermal analysis (TG/DTA). The acute toxicity of the extract was evaluated in vivo in rodents. The results indicate significant additive action of the extract on synthetic antibiotics, considerable antioxidant activity and absence of toxicity. This extract shows high potential for the development of formulations for antimicrobial therapy when used with a vegetable-active ingredient.

Evaluation of the Interaction between the Poincianella pyramidalis (Tul.) LP Queiroz Extract and Antimicrobials Using Biological and Analytical Models

PubMed Central

Santana, Cleildo P.; Medeiros, Francinalva D.; Felismino, Délcio C.; Santos, Vanda L.; Catão, Raïssa Mayer R.; Coutinho, Henrique Douglas M.

2016-01-01

Poincianella pyramidalis (Tul.) LP Queiroz (Fabaceae) is an endemic tree of northeastern Brazil, occurring mainly in the Caatinga. Its medicinal use is widespread and is an important therapeutic option against diarrhea, dysentery, and respiratory and urinary infections, among other diseases. In this study we determined the chemical marker and evaluated the interaction between P. pyramidalis extract and a commercial antimicrobial through the use of biological and analytical models. To obtain the extract, an ethanol-water mixture (50:50 v/v) was used as solvent. It was nebulized in a spray dryer using colloidal silicon dioxide as a drying adjuvant. The extract (ENPp) was subjected to HPLC analysis to verify the presence of certain secondary metabolites. The Minimum Inhibitory Concentration (MIC) of the extract against Gram-negative bacteria was determined by broth microdilution and the MIC of synthetic antimicrobial drugs in the presence and absence of the extract. The antioxidant activity of ENPp was evaluated by the DPPH method. The compatibility between the antimicrobial and the extract was evaluated by thermal analysis (TG/DTA). The acute toxicity of the extract was evaluated in vivo in rodents. The results indicate significant additive action of the extract on synthetic antibiotics, considerable antioxidant activity and absence of toxicity. This extract shows high potential for the development of formulations for antimicrobial therapy when used with a vegetable-active ingredient. PMID:27192209

76 FR 18564 - Government-Owned Inventions; Availability for Licensing

Federal Register 2010, 2011, 2012, 2013, 2014

2011-04-04

... attractive antimicrobial target. The chrysophaetin exhibits antimicrobial activity against drug resistant... analogues will show similar antimicrobial activity to the natural products and will utilize the same... distinct antimicrobial compounds. Attack newly validated antibacterial targeted protein FtsZ. These...

Antimicrobial, antibiofilm and antitumor activities of essential oil of Agastache rugosa from Xinjiang, China.

PubMed

Haiyan, Gong; Lijuan, He; Shaoyu, Li; Chen, Zhang; Ashraf, Muhammad Aqeel

2016-07-01

In the study, we evaluated chemical composition and antimicrobial, antibiofilm, and antitumor activities of essential oils from dried leaf essential oil of leaf and flower of Agastache rugosa for the first time. Essential oil of leaf and flower was evaluated with GC and GC-MS methods, and the essential oil of flower revealed the presence of 21 components, whose major compounds were pulegone (34.1%), estragole (29.5%), and p-Menthan-3-one (19.2%). 26 components from essential oil of leaf were identified, the major compounds were p-Menthan-3-one (48.8%) and estragole (20.8%). At the same time, essential oil of leaf, there is a very effective antimicrobial activity with MIC ranging from 9.4 to 42 μg ml(-1) and potential antibiofilm, antitumor activities for essential oils of flower and leaf essential oil of leaf. The study highlighted the diversity in two different parts of A. rugosa grown in Xinjiang region and other places, which have different active constituents. Our results showed that this native plant may be a good candidate for further biological and pharmacological investigations.

Inhibitory and antimicrobial activities of OGTI and HV-BBI peptides, fragments and analogs derived from amphibian skin.

PubMed

Dębowski, Dawid; Łukajtis, Rafał; Łęgowska, Anna; Karna, Natalia; Pikuła, Michał; Wysocka, Magdalena; Maliszewska, Irena; Sieńczyk, Marcin; Lesner, Adam; Rolka, Krzysztof

2012-06-01

A series of linear and cyclic fragments and analogs of two peptides (OGTI and HV-BBI) isolated from skin secretions of frogs were synthesized by the solid-phase method. Their inhibitory activity against several serine proteinases: bovine β-trypsin, bovine α-chymotypsin, human leukocyte elastase and cathepsin G from human neutrophils, was investigated together with evaluation of their antimicrobial activities against Gram-negative bacteria (Escherichia coli) and Gram-positive species isolated from patients (Staphylococcus aureus, Staphylococcus epidermidis, Enterococcus sp., Streptococcus sp.). The cytotoxicity of the selected peptides toward an immortal human skin fibroblast cell line was also determined. Three peptides: HV-BBI, its truncated fragment HV-BBI(3-18) and its analog [Phe(8)]HV-BBI can be considered as bifunctional compounds with inhibitory as well as antibacterial properties. OGTI, although it did not display trypsin inhibitory activity as previously reported in the literature, exerted antimicrobial activity toward S. epidermidis. In addition, under our experimental conditions, this peptide did not show cytotoxicity. Copyright © 2012 Elsevier Inc. All rights reserved.

Membrane interaction of chrysophsin-1, a histidine-rich antimicrobial peptide from red sea bream.

PubMed

Mason, A James; Bertani, Philippe; Moulay, Gilles; Marquette, Arnaud; Perrone, Barbara; Drake, Alex F; Kichler, Antoine; Bechinger, Burkhard

2007-12-25

Chrysophsin-1 is an amphipathic alpha-helical antimicrobial peptide produced in the gill cells of red sea bream. The peptide has broad range activity against both Gram-positive and Gram-negative bacteria but is more hemolytic than other antimicrobial peptides such as magainin. Here we explore the membrane interaction of chrysophsin-1 and determine its toxicity, in vitro, for human lung fibroblasts to obtain a mechanism for its antimicrobial activity and to understand the role of the unusual C-terminal RRRH sequence. At intermediate peptide concentrations, solid-state NMR methods reveal that chrysophsin-1 is aligned parallel to the membrane surface and the lipid acyl chains in mixed model membranes are destabilized, thereby being in agreement with models where permeabilization is an effect of transient membrane disruption. The C-terminal RRRH sequence was shown to have a large effect on the insertion of the peptide into membranes with differing lipid compositions and was found to be crucial for pore formation and toxicity of the peptide to fibroblasts. The combination of biophysical data and cell-based assays suggests likely mechanisms involved in both the antibiotic and toxic activity of chrysophsins.

Chemical composition and antimicrobial activity of the essential oil of apricot seed.

PubMed

Lee, Hyun-Hee; Ahn, Jeong-Hyun; Kwon, Ae-Ran; Lee, Eun Sook; Kwak, Jin-Hwan; Min, Yu-Hong

2014-12-01

In traditional oriental medicine, apricot (Prunus armeniaca L.) seed has been used to treat skin diseases such as furuncle, acne vulgaris and dandruff, as well as coughing, asthma and constipation. This study describes the phytochemical profile and antimicrobial potential of the essential oil obtained from apricot seeds (Armeniacae Semen). The essential oil isolated by hydrodistillation was analysed by gas chromatography-mass spectroscopy. Benzaldehyde (90.6%), mandelonitrile (5.2%) and benzoic acid (4.1%) were identified. Disc diffusion, agar dilution and gaseous contact methods were performed to determine the antimicrobial activity against 16 bacteria and two yeast species. The minimum inhibitory concentrations ranged from 250 to 4000, 500 to 2000 and 250 to 1000 µg/mL for Gram-positive bacteria, Gram-negative bacteria and yeast strains, respectively. The minimum inhibitory doses by gaseous contact ranged from 12.5 to 50, 12.5 to 50 and 3.13 to 12.5 mg/L air for Gram-positive bacteria, Gram-negative bacteria and yeast strains, respectively. The essential oil exhibited a variable degree of antimicrobial activity against a range of bacteria and yeasts tested. Copyright © 2014 John Wiley & Sons, Ltd.

A Comparison between Characterization and Biological Properties of Brazilian Fresh and Aged Propolis

PubMed Central

Schmidt, Eduardo Morgado; Stock, Daniele; Chada, Fabio José Garcia; Finger, Daiane; Christine Helena Frankland Sawaya, Alexandra; Eberlin, Marcos Nogueira; Felsner, Maria Lurdes; Quináia, Sueli Pércio; Torres, Yohandra Reyes

2014-01-01

Objective. As propolis is a highly valued bee product, we aimed to verify the quality of aged propolis, investigating their phenolic and flavonoid composition, levels of toxic metals, radical scavenging and antimicrobial activities. Material and Methods. Samples of fresh and aged propolis of six different beekeepers, from the same geographical location, were investigated in terms of their phenolic and flavonoid composition and levels of Pb, Cd, and Cr, as well as radical scavenging and antimicrobial activities. Results. The two groups of propolis had similar qualitative composition by HPLC-PDA and ESI(-)-MS. Fresh propolis and aged propolis show no differences when average values of extraction yield, flavonoids, EC50, or MIC were compared and both types of propolis showed good antimicrobial activity at low concentrations. Only levels of phenolic compounds were higher in fresh propolis. Conclusion. The propolis samples considered in this study, aged or fresh, had similar qualitative composition, although they were collected in different periods. Samples only differed in their levels of total phenolic content. Moreover, aged propolis conserves significant radical scavenging and antimicrobial properties. We suggest that aged propolis should not be discarded but explored for alternative applications. PMID:25530958

Synthesis of New Nitrofluoroquinolone Derivatives with Novel Anti-Microbial Properties against Metronidazole Resistant H. pylori.

PubMed

Abu-Qatouseh, Luay; Abu-Sini, Mohammad; Mayyas, Amal; Al-Hiari, Yusuf; Darwish, Rula; Aburjai, Talal

2017-01-04

One of the major therapeutic approaches to preventing relapse and accelerating the healing of duodenal and gastric ulcers is the eradication of Helicobacter pylori . Due to the emergence of antibiotic resistance among clinical strains of H. pylori , alternative approaches using newly discovered antimicrobial agents in combination with the standard regimens for the treatment of H. pylori are increasingly needed. The purpose of the present study was to investigate the effect of newly synthesized 8-nitroflouroqunolone derivatives when used either alone or when combined with metronidazole against metronidazole-resistant H. pylori . Based on the standard antimicrobial susceptibility testing methods and checkerboard titration assay, all of the tested compounds showed interesting antimicrobial activity against 12 clinical strains of H. pylori , with the best in vitro effect for compound 3c . In addition, synergistic and additive activities of some of the tested compounds were observed when combined with metronidazole. Furthermore, among the tested nitroflouroquinolone derivatives, compound 3b showed significant urease inhibition activity with IC 50 of 62.5 µg/mL. These results suggest that 8-nitroflouroquinolone derivatives may have a useful role in combination with anti- H. pylori drugs in the management of H. pylori -associated diseases.

Embedment of silver into temperature- and pH-responsive microgel for the development of smart textiles with simultaneous moisture management and controlled antimicrobial activities.

PubMed

Štular, Danaja; Jerman, Ivan; Naglič, Iztok; Simončič, Barbara; Tomšič, Brigita

2017-03-01

Silver nanoparticles were embedded into a temperature- and pH-responsive microgel based on poly-(N-isopropylacrylamide) and chitosan (PNCS) before or after its application to cotton fabric to create a smart stimuli-responsive textile with simultaneous moisture management and controlled antimicrobial activities. Two different methods of silver embedment into the PNCS microgel using two different forms of silver nanoparticles were studied, i.e., in-situ synthesis of AgCl nanocrystals into PNCS microgel particles that had previously been applied to cotton fabric, as well as the direct incorporation of colloidal silver into the microgel suspension prior to its deposition on cellulose fibres. SEM and FT-IR analysis were employed to determine the morphological and chemical changes of the modified cotton fibres, while EDS and ICP MS analysis were used to confirm the presence of the silver nanoparticles. The influence of silver embedment on the swelling/deswelling activity of the PNCS microgel was studied using the temperature- and pH-responsiveness, as determined by the moisture content, water vapour transmission rate and water uptake. The antimicrobial activity against the bacteria Staphylococcus aureus and Escherichia coli was assessed. Regardless of the embedment technique, the presence of silver nanoparticles resulted in impaired moisture management activity of the studied microgel. The PNCS microgel proved to be a suitable carrier of antimicrobial agents, assuring the effective controlled release of silver triggered by changes in the temperature and pH of the surroundings, which granted the cotton fabric excellent antimicrobial activity against Gram-negative E. coli (>99%) and Gram-positive S. aureus (>85%). Copyright © 2016 Elsevier Ltd. All rights reserved.

Antimicrobial and antioxidant activities of substituted 4H-1, 4-benzothiazines

NASA Astrophysics Data System (ADS)

Sharma, Praveen Kumar; Chaucer, Puneet; Kumar, Gulshan; Parihar, Leena

2017-07-01

Antioxidant and antimicrobial activity of substituted benzothiazine was investigated. Antioxidant activity of 3,7-dimethyl-2-(4'-morpholinylcarbonyl)-4H-1,4-benzothiazine was tested by the use of 2-diphenyl-1-picrylhydrazyl radical(DPPH). In addition 3,7-dimethyl-2-(4'-morpholinylcarbonyl)-4H-1,4-benzothiazine was examined for its antimicrobial activity against bacteria, Bacillus subtilis, B. flexus, B. alkalophilus, as well as their antifungal activity against Aspergillus nigrum, A. Flexus and show potential antimicrobial activities.

Improved antimicrobial activity of Pediococcus acidilactici against Salmonella Gallinarum by UV mutagenesis and genome shuffling.

PubMed

Han, Geon Goo; Song, Ahn Ah; Kim, Eun Bae; Yoon, Seong-Hyun; Bok, Jin-Duck; Cho, Chong-Su; Kil, Dong Yong; Kang, Sang-Kee; Choi, Yun-Jaie

2017-07-01

Pediococcus acidilactici is a widely used probiotic, and Salmonella enterica serovar Gallinarum (SG) is a significant pathogen in the poultry industry. In this study, we improved the antimicrobial activity of P. acidilactici against SG using UV mutation and genome shuffling (GS). To improve antimicrobial activity against SG, UV mutagenesis was performed against wild-type P. acidilactici (WT), and five mutants showed improved antimicrobial activity. To further improve antimicrobial activity, GS was performed on five UV mutants. Following GS, four mutants showed improved antimicrobial activity compared with the UV mutants and WT. The antimicrobial activity of GS1 was highest among the mutants; however, the activity was reduced when the culture supernatant was treated with proteinase K, suggesting that the improved antimicrobial activity is due to a proteinous substance such as bacteriocin. To validate the activity of GS1 in vivo, we designed multi-species probiotics and performed broiler feeding experiments. Groups consisted of no treatment (NC), avilamycin-treated (PC), probiotic group 1 containing WT (T1), and probiotic group 2 containing GS1 (T2). In broiler feeding experiments, coliform bacteria were significantly reduced in T2 compared with NC, PC, and T1. The cecal microbiota was modulated and pathogenic bacteria were reduced by GS1 oral administration. In this study, GS1 showed improved antimicrobial activity against SG in vitro and reduced pathogenic bacteria in a broiler feeding experiment. These results suggest that GS1 can serve as an efficient probiotic, as an alternative to antibiotics in the poultry industry.

Preparation of an agar-silver nanoparticles (A-AgNp) film for increasing the shelf-life of fruits.

PubMed

Gudadhe, Janhavi A; Yadav, Alka; Gade, Aniket; Marcato, Priscyla D; Durán, Nelson; Rai, Mahendra

2014-12-01

Preparation of protective coating possessing antimicrobial properties is present day need as they increase the shelf life of fruits and vegetables. In the present study, preparation of agar-silver nanoparticle film for increasing the shelf life of fruits is reported. Silver nanoparticles (Ag-NPs) biosynthesised using an extract of Ocimum sanctum leaves, were mixed with agar-agar to prepare an agar-silver nanoparticles (A-AgNp) film. This film was surface-coated over the fruits, Citrus aurantifolium (Thornless lime) and Pyrus malus (Apple), and evaluated for the determination of antimicrobial activity of A-AgNp films using disc diffusion method, weight loss and shelf life of fruits. This study demonstrates that these A-AgNp films possess antimicrobial activity and also increase the shelf life of fruits.

Enhanced antibactericidal function of W4+-doped titania-coated nickel ferrite composite nanoparticles: a biomaterial system.

PubMed

Sunkara, B K; Misra, R D K

2008-03-01

The study demonstrates a distinct enhancement of antimicrobial activity of W4+-doped titania that is coated on nickel ferrite nanoparticles in comparison to undoped titania. The composite nanoparticles were synthesized by uniquely combining reverse micelle and chemical hydrolysis synthesis methods [Rana S, Rawat J, Misra RDK, Acta Biomater 2005;1:691]. The superior antimicrobial activity of W4+-doped titania is related to the inhibition of electron-hole recombination and decrease in the band gap energy of titania. The function of the ferrite is to facilitate the removal of nanoparticles from the sprayed surface using a small magnetic field. The coating of ferrite nanoparticles with titania retains superparamagnetic character and magnetic strength of composite nanoparticles signifying non-deterioration of magnetic properties and promoting their use as removable antimicrobial photocatalyst nanoparticles.

Structure-Activity Relationship of Benzophenanthridine Alkaloids from Zanthoxylum rhoifolium Having Antimicrobial Activity

PubMed Central

Tavares, Luciana de C.; Zanon, Graciane; Weber, Andréia D.; Neto, Alexandre T.; Mostardeiro, Clarice P.; Da Cruz, Ivana B. M.; Oliveira, Raul M.; Ilha, Vinicius; Dalcol, Ionara I.; Morel, Ademir F.

2014-01-01

Zanthoxylum rhoifolium (Rutaceae) is a plant alkaloid that grows in South America and has been used in Brazilian traditional medicine for the treatment of different health problems. The present study was designed to evaluate the antimicrobial activity of the steam bark crude methanol extract, fractions, and pure alkaloids of Z. rhoifolium. Its stem bark extracts exhibited a broad spectrum of antimicrobial activity, ranging from 12.5 to 100 µg/mL using bioautography method, and from 125 to 500 µg/mL in the microdilution bioassay. From the dichloromethane basic fraction, three furoquinoline alkaloids (1–3), and nine benzophenanthridine alkaloids (4–12) were isolated and the antimicrobial activity of the benzophenanthridine alkaloids is discussed in terms of structure-activity relationships. The alkaloid with the widest spectrum of activity was chelerythrine (10), followed by avicine (12) and dihydrochelerythrine (4). The minimal inhibitory concentrations of chelerythrine, of 1.50 µg/mL for all bacteria tested, and between 3.12 and 6.25 µg/mL for the yeast tested, show this compound to be a more powerful antimicrobial agent when compared with the other active alkaloids isolated from Z. rhoifolium. To verify the potential importance of the methylenedioxy group (ring A) of these alkaloids, chelerythrine was selected to represent the remainder of the benzophenanthridine alkaloids isolated in this work and was subjected to a demethylation reaction giving derivative 14. Compared to chelerythrine, the derivative (14) was less active against the tested bacteria and fungi. Kinetic measurements of the bacteriolytic activities of chelerythrine against the bacteria Bacillus subtilis (Gram-positive) and Escherichia coli (Gram-negative) were determined by optical density based on real time assay, suggesting that its mechanism of action is not bacteriolytic. The present study did not detect hemolytic effects of chelerythrine on erythrocytes and found a protective effect considering the decrease in TBARS and AOPP (advanced oxidized protein products) levels when compared to the control group. PMID:24824737

Direct and indirect antimicrobial effects and antioxidant activity of Cordia gilletii De Wild (Boraginaceae).

PubMed

Okusa, P N; Penge, O; Devleeschouwer, M; Duez, P

2007-07-25

Cordia gilletii De Wild (Boraginaceae) root bark is traditionally used in Democratic Republic of Congo (DRC) for the treatment of various disorders, including malaria, diarrhea, wounds and skin diseases; part of these activities may rely on antimicrobial and antioxidant properties. Successive extracts of root barks powder with n-hexane, dichloromethane, ethyl acetate, methanol and water were tested for antimicrobial activity, both direct and indirect (antibiotic resistance reversal), against 10 strains of bacteria and 1 strain of fungi by broth microdilution and agar diffusion methods. The eventual synergy between plant extracts and antibiotics was investigated by the determination of the fractional inhibitory concentration index (FIC index). The methanol extract showed direct antimicrobial activity against all tested microorganisms with minimum inhibitory concentrations (MIC) ranging between 125 and 1000 microg/ml, whereas the ethyl acetate and the dichloromethane extracts showed activity on four and three strains, respectively. 200 microg/ml of n-hexane and dichloromethane extracts decreased the MICs of penicillin and streptomycin 4-64-fold for methicillin-resistant Staphylococcus aureus. A synergistic effect was found between the methanol extract and tetracycline, whereas additive effects were observed for the other combinations tested. The methanol and dichloromethane extracts showed the greater antioxidant activity by scavenging the free radical DPPH with IC(50) values of 3.2 and 8.1 microg/ml, respectively. These results support the use of the plant in the treatment of infectious diseases and wounds; they warrant further studies as to the nature of active compounds.

Cotton textiles modified with citric acid as efficient anti-bacterial agent for prevention of nosocomial infections

PubMed Central

Bischof Vukušić, Sandra; Flinčec Grgac, Sandra; Budimir, Ana; Kalenić, Smilja

2011-01-01

Aim To study the antimicrobial activity of citric acid (CA) and sodium hypophosphite monohydrate (SHP) against gram-positive and gram-negative bacteria, and to determine the influence of conventional and microwave thermal treatments on the effectiveness of antimicrobial treatment of cotton textiles. Method Textile material was impregnated with CA and SHP solution and thermally treated by either conventional or microwave drying/curing treatment. Antibacterial effectiveness was tested according to the ISO 20743:2009 standard, using absorption method. The surfaces were morphologically observed by scanning electron microscopy, while physical characteristics were determined by wrinkle recovery angles method (DIN 53 891), tensile strength (DIN 53 837), and whiteness degree method (AATCC 110-2000). Results Cotton fabric treated with CA and SHP showed significant antibacterial activity against MRSA (6.38 log10 treated by conventional drying and 6.46 log10 treated by microwave drying before washing, and 6.90 log10 and 7.86 log10, respectively, after 1 cycle of home domestic laundering washing [HDLW]). Antibacterial activity was also remarkable against S. aureus (4.25 log10 by conventional drying, 4.58 log10 by microwave drying) and against P. aeruginosa (1.93 log10 by conventional and 4.66 log10 by microwave drying). Antibacterial activity against P. aeruginosa was higher in samples subjected to microwave drying/curing than in those subjected to conventional drying/curing. As expected, antibacterial activity was reduced after 10 HDLW cycles but the compound was still effective. The surface of the untreated cotton polymer was smooth, while minor erosion stripes appeared on the surfaces treated with antimicrobial agent, and long and deep stripes were found on the surface of the washed sample. Conclusion CA can be used both for the disposable (non-durable) materials (gowns, masks, and cuffs for blood pressure measurement) and the materials that require durability to laundering. The current protocols and initiatives in infection control could be improved by the use of antimicrobial agents applied on cotton carbohydrate polymer. PMID:21328723

Antimicrobial activity of ProRoot MTA in contact with blood

PubMed Central

Farrugia, C.; Baca, P.; Camilleri, J.; Arias Moliz, M. T.

2017-01-01

Dental materials based on Portland cement, which is used in the construction industry have gained popularity for clinical use due to their hydraulic properties, the interaction with tooth tissue and their antimicrobial properties. The antimicrobial properties are optimal in vitro. However in clinical use contact with blood may affect the antimicrobial properties. This study aims to assess whether antimicrobial properties of the Portland cement-based dental cements such as mineral trioxide aggregate (MTA) are also affected by contact with blood present in clinical situations. ProRoot MTA, a Portland cement-based dental cement was characterized following contact with water, or heparinized blood after 1 day and 7 days aging. The antimicrobial activity under the mentioned conditions was assessed using 3 antimicrobial tests: agar diffusion test, direct contact test and intratubular infection test. MTA in contact with blood was severely discoloured, exhibited an additional phosphorus peak in elemental analysis, no calcium hydroxide peaks and no areas of bacterial inhibition growth in the agar diffusion test were demonstrated. ProRoot MTA showed limited antimicrobial activity, in both the direct contact test and intratubular infection test. When aged in water ProRoot MTA showed higher antimicrobial activity than when aged in blood. Antimicrobial activity reduced significantly after 7 days. Further assessment is required to investigate behaviour in clinical situations. PMID:28128328

Antibacterial and antioxidant activities in extracts of fully grown cladodes of 8 cultivars of cactus pear.

PubMed

Sánchez, E; Dávila-Aviña, J; Castillo, S L; Heredia, N; Vázquez-Alvarado, R; García, S

2014-04-01

The antimicrobial and antioxidant activities of some cultivars of the nopal cactus have not been determined. In this study, 8 cultivars of nopal cacti from Mexico were assayed for phenolic content, antioxidant activities, and antimicrobial activities against Campylobacter Jejuni, Vibrio cholera, and Clostridium Perfringens. Plant material was washed, dried, and macerated in methanol. Minimum bactericidal concentrations (MBCs) were determined using the broth microdilution method. Antioxidant activities were quantitatively determined using spectrophotometric methods. The MCBs of the nopal cacti ranged from 1.1 to 12.5 mg/mL for c. jejuni, 4.4 to 30 mg/mL for V. cholera, and 0.8 to 16 mg/mL for C. perfringens in the cultivars Cardon Blanco, Real de Catorce, and Jalpa, respectively. High quantities of total phenols and total flavonoids were found in the Jalpa cacti (3.80 mg of gallic acid equivalent GAE/g dry weight [DW] and 36.64 mg of quercetin equivalents [QE]/g DW, respectively). 2,2-Diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activities (RSA) were correlated to bioactive compound contents. The Villanueva cacti had the highest %RSA at 42.31%, and the lowest activity was recorded in Copena V1 at 19.98%. In conclusion, we found that some of the 8 cactus pear cultivars studied may be used for their antioxidant compounds or antimicrobials to control or prevent the contamination of foods. © 2014 Institute of Food Technologists®

Analgesic, antibacterial and central nervous system depressant activities of Albizia procera leaves

PubMed Central

Khatoon, Mst. Mahfuza; Khatun, Mst. Hajera; Islam, Md. Ekramul; Parvin, Mst. Shahnaj

2014-01-01

Objective To ascertain analgesic, antibacterial and central nervous system (CNS) depressant activities of ethyl acetate, dichloromethane and carbon tetrachloride fractions of methanol extract of Albizia procera (A. procera) leaves. Methods Leaves extracts of A. procera were tested for analgesic activity by acetic acid induced and formalin test method in mice. The in vitro antibacterial activity was performed by agar well diffusion method. CNS depressant activity was evaluated by hole cross and open field tests. Results All the extracts at 200 mg/kg exhibited significant (P<0.01) analgesic activity in acetic acid induced and formalin tests method in mice. Analgesic activity of the ethyl acetate fraction was almost same like as standard drug indomethacin in acetic acid induced method. The CNS depressant activity of the extracts at 500 mg/kg was comparable to the positive control diazepam as determined by hole cross and open field test method. The extracts exhibited moderate antimicrobial activity against all the tested microorganisms (Staphylococcus aureus, Bacillus cereus, Pseudomonas aeruginosa, Esherichia coli, Shigella soneii, Shigella boydii) at concentration of 0.8 mg/disc. The measured diameter of zone of inhibition for the extracts was within the range of 7 to 12 mm which was less than the standard kanamycin (16-24 mm). Conclusions It is concluded that all the extracts possess potential analgesic and CNS depressants activity. This study also showed that different fractions of methanol extract could be potential sources of new antimicrobial agents. PMID:25182551

Chemical Composition and Antimicrobial Activity of Essential Oils from the Aerial Parts of Asteriscus graveolens (Forssk.) Less. and Pulicaria incisa (Lam.) DC.: Two Asteraceae Herbs Growing Wild in the Hoggar.

PubMed

Chaib, Faiza; Allali, Hocine; Bennaceur, Malika; Flamini, Guido

2017-08-01

In recent years, antimicrobial activities of essential oils have been intensively explored, mainly in researching and developing new antimicrobial agents to overcome microbial resistance. The present study investigates the chemical composition and antimicrobial activities of essential oils obtained from two Asteraceae: Asteriscus graveolens (Forssk.) Less. and Pulicaria incisa (Lam.) DC. Chemical analysis was performed using a combination of capillary GC-FID and GC/MS analytical techniques. The major component of Asteriscus graveolens were cis-chrysanthenyl acetate (31.1%), myrtenyl acetate (15.1%), and kessane (11.5%), while for Pulicaria incisa the main components were chrysanthenone (45.3%) and 2,6-dimethylphenol (12.6%). The oils obtained from the aerial parts were tested against sixteen microbial strains by agar well diffusion technique and dilution methods and showed minimum inhibitory concentrations (MIC) in the range of 19 - 1250 μg/ml. A good antibacterial activity against a common nosocomial pathogen, Acinetobacter baumanniiATCC 19606 was observed, especially from Pulicaria incisa essential oil, with a MIC value up to 19 μg/ml. These results give significant information about the pharmacological activity of these essential oils, which suggest their benefits to human health, having the potential to be used for medical purposes. © 2017 Wiley-VHCA AG, Zurich, Switzerland.