[Comparative genomics and evolutionary analysis of CRISPR loci in acetic acid bacteria].

PubMed

Xia, Kai; Liang, Xin-le; Li, Yu-dong

2015-12-01

The clustered regularly interspaced short palindromic repeat (CRISPR) is a widespread adaptive immunity system that exists in most archaea and many bacteria against foreign DNA, such as phages, viruses and plasmids. In general, CRISPR system consists of direct repeat, leader, spacer and CRISPR-associated sequences. Acetic acid bacteria (AAB) play an important role in industrial fermentation of vinegar and bioelectrochemistry. To investigate the polymorphism and evolution pattern of CRISPR loci in acetic acid bacteria, bioinformatic analyses were performed on 48 species from three main genera (Acetobacter, Gluconacetobacter and Gluconobacter) with whole genome sequences available from the NCBI database. The results showed that the CRISPR system existed in 32 species of the 48 strains studied. Most of the CRISPR-Cas system in AAB belonged to type I CRISPR-Cas system (subtype E and C), but type II CRISPR-Cas system which contain cas9 gene was only found in the genus Acetobacter and Gluconacetobacter. The repeat sequences of some CRISPR were highly conserved among species from different genera, and the leader sequences of some CRISPR possessed conservative motif, which was associated with regulated promoters. Moreover, phylogenetic analysis of cas1 demonstrated that they were suitable for classification of species. The conservation of cas1 genes was associated with that of repeat sequences among different strains, suggesting they were subjected to similar functional constraints. Moreover, the number of spacer was positively correlated with the number of prophages and insertion sequences, indicating the acetic acid bacteria were continually invaded by new foreign DNA. The comparative analysis of CRISR loci in acetic acid bacteria provided the basis for investigating the molecular mechanism of different acetic acid tolerance and genome stability in acetic acid bacteria.

Effect of aspartic acid and glutamate on metabolism and acid stress resistance of Acetobacter pasteurianus.

PubMed

Yin, Haisong; Zhang, Renkuan; Xia, Menglei; Bai, Xiaolei; Mou, Jun; Zheng, Yu; Wang, Min

2017-06-15

Acetic acid bacteria (AAB) are widely applied in food, bioengineering and medicine fields. However, the acid stress at low pH conditions limits acetic acid fermentation efficiency and high concentration of vinegar production with AAB. Therefore, how to enhance resistance ability of the AAB remains as the major challenge. Amino acids play an important role in cell growth and cell survival under severe environment. However, until now the effects of amino acids on acetic fermentation and acid stress resistance of AAB have not been fully studied. In the present work the effects of amino acids on metabolism and acid stress resistance of Acetobacter pasteurianus were investigated. Cell growth, culturable cell counts, acetic acid production, acetic acid production rate and specific production rate of acetic acid of A. pasteurianus revealed an increase of 1.04, 5.43, 1.45, 3.30 and 0.79-folds by adding aspartic acid (Asp), and cell growth, culturable cell counts, acetic acid production and acetic acid production rate revealed an increase of 0.51, 0.72, 0.60 and 0.94-folds by adding glutamate (Glu), respectively. For a fully understanding of the biological mechanism, proteomic technology was carried out. The results showed that the strengthening mechanism mainly came from the following four aspects: (1) Enhancing the generation of pentose phosphates and NADPH for the synthesis of nucleic acid, fatty acids and glutathione (GSH) throughout pentose phosphate pathway. And GSH could protect bacteria from low pH, halide, oxidative stress and osmotic stress by maintaining the viability of cells through intracellular redox equilibrium; (2) Reinforcing deamination of amino acids to increase intracellular ammonia concentration to maintain stability of intracellular pH; (3) Enhancing nucleic acid synthesis and reparation of impaired DNA caused by acid stress damage; (4) Promoting unsaturated fatty acids synthesis and lipid transport, which resulted in the improvement of cytomembrane fluidity, stability and integrity. The present work is the study to show the effectiveness of Asp and Glu on metabolism and acid stress resistance of A. pasteurianus as well as their working mechanism. The research results will be helpful for development of nutrient salts, the optimization and regulation of high concentration of cider vinegar production process.

Spontaneous organic cocoa bean box fermentations in Brazil are characterized by a restricted species diversity of lactic acid bacteria and acetic acid bacteria.

PubMed

Papalexandratou, Zoi; Vrancken, Gino; De Bruyne, Katrien; Vandamme, Peter; De Vuyst, Luc

2011-10-01

Spontaneous organic cocoa bean box fermentations were carried out on two different farms in Brazil. Physical parameters, microbial growth, bacterial species diversity [mainly lactic acid bacteria (LAB) and acetic acid bacteria (AAB)], and metabolite kinetics were monitored, and chocolates were produced from the fermented dry cocoa beans. The main end-products of the catabolism of the pulp substrates (glucose, fructose, and citric acid) by yeasts, LAB, and AAB were ethanol, lactic acid, mannitol, and/or acetic acid. Lactobacillus fermentum and Acetobacter pasteurianus were the predominating bacterial species of the fermentations as revealed through (GTG)(5)-PCR fingerprinting of isolates and PCR-DGGE of 16S rRNA gene PCR amplicons of DNA directly extracted from fermentation samples. Fructobacillus pseudoficulneus, Lactobacillus plantarum, and Acetobacter senegalensis were among the prevailing species during the initial phase of the fermentations. Also, three novel LAB species were found. This study emphasized the possible participation of Enterobacteriaceae in the cocoa bean fermentation process. Tatumella ptyseos and Tatumella citrea were the prevailing enterobacterial species in the beginning of the fermentations as revealed by 16S rRNA gene-PCR-DGGE. Finally, it turned out that control over a restricted bacterial species diversity during fermentation through an ideal post-harvest handling of the cocoa beans will allow the production of high-quality cocoa and chocolates produced thereof, independent of the fermentation method or farm. Copyright © 2011 Elsevier Ltd. All rights reserved.

Dynamics and Biodiversity of Populations of Lactic Acid Bacteria and Acetic Acid Bacteria Involved in Spontaneous Heap Fermentation of Cocoa Beans in Ghana▿

PubMed Central

Camu, Nicholas; De Winter, Tom; Verbrugghe, Kristof; Cleenwerck, Ilse; Vandamme, Peter; Takrama, Jemmy S.; Vancanneyt, Marc; De Vuyst, Luc

2007-01-01

The Ghanaian cocoa bean heap fermentation process was studied through a multiphasic approach, encompassing both microbiological and metabolite target analyses. A culture-dependent (plating and incubation, followed by repetitive-sequence-based PCR analyses of picked-up colonies) and culture-independent (denaturing gradient gel electrophoresis [DGGE] of 16S rRNA gene amplicons, PCR-DGGE) approach revealed a limited biodiversity and targeted population dynamics of both lactic acid bacteria (LAB) and acetic acid bacteria (AAB) during fermentation. Four main clusters were identified among the LAB isolated: Lactobacillus plantarum, Lactobacillus fermentum, Leuconostoc pseudomesenteroides, and Enterococcus casseliflavus. Other taxa encompassed, for instance, Weissella. Only four clusters were found among the AAB identified: Acetobacter pasteurianus, Acetobacter syzygii-like bacteria, and two small clusters of Acetobacter tropicalis-like bacteria. Particular strains of L. plantarum, L. fermentum, and A. pasteurianus, originating from the environment, were well adapted to the environmental conditions prevailing during Ghanaian cocoa bean heap fermentation and apparently played a significant role in the cocoa bean fermentation process. Yeasts produced ethanol from sugars, and LAB produced lactic acid, acetic acid, ethanol, and mannitol from sugars and/or citrate. Whereas L. plantarum strains were abundant in the beginning of the fermentation, L. fermentum strains converted fructose into mannitol upon prolonged fermentation. A. pasteurianus grew on ethanol, mannitol, and lactate and converted ethanol into acetic acid. A newly proposed Weissella sp., referred to as “Weissella ghanaensis,” was detected through PCR-DGGE analysis in some of the fermentations and was only occasionally picked up through culture-based isolation. Two new species of Acetobacter were found as well, namely, the species tentatively named “Acetobacter senegalensis” (A. tropicalis-like) and “Acetobacter ghanaensis” (A. syzygii-like). PMID:17277227

The microbiology of Bandji, palm wine of Borassus akeassii from Burkina Faso: identification and genotypic diversity of yeasts, lactic acid and acetic acid bacteria.

PubMed

Ouoba, L I I; Kando, C; Parkouda, C; Sawadogo-Lingani, H; Diawara, B; Sutherland, J P

2012-12-01

To investigate physicochemical characteristics and especially genotypic diversity of the main culturable micro-organisms involved in fermentation of sap from Borassus akeassii, a newly identified palm tree from West Africa. Physicochemical characterization was performed using conventional methods. Identification of micro-organisms included phenotyping and sequencing of: 26S rRNA gene for yeasts, 16S rRNA and gyrB genes for lactic acid bacteria (LAB) and acetic acid bacteria (AAB). Interspecies and intraspecies genotypic diversities of the micro-organisms were screened respectively by amplification of the ITS1-5.8S rDNA-ITS2/16S-23S rDNA ITS regions and repetitive sequence-based PCR (rep-PCR). The physicochemical characteristics of samples were: pH: 3.48-4.12, titratable acidity: 1.67-3.50 mg KOH g(-1), acetic acid: 0.16-0.37%, alcohol content: 0.30-2.73%, sugars (degrees Brix): 2.70-8.50. Yeast included mainly Saccharomyces cerevisiae and species of the genera Arthroascus, Issatchenkia, Candida, Trichosporon, Hanseniaspora, Kodamaea, Schizosaccharomyces, Trigonopsis and Galactomyces. Lactobacillus plantarum was the predominant LAB species. Three other species of Lactobacillus were also identified as well as isolates of Leuconostoc mesenteroides, Fructobacillus durionis and Streptococcus mitis. Acetic acid bacteria included nine species of the genus Acetobacter with Acetobacter indonesiensis as predominant species. In addition, isolates of Gluconobacter oxydans and Gluconacetobacter saccharivorans were also identified. Intraspecies diversity was observed for some species of micro-organisms including four genotypes for Acet. indonesiensis, three for Candida tropicalis and Lactobacillus fermentum and two each for S. cerevisiae, Trichosporon asahii, Candida pararugosa and Acetobacter tropicalis. fermentation of palm sap from B. akeassii involved multi-yeast-LAB-AAB cultures at genus, species and intraspecies level. First study describing microbiological and physicochemical characteristics of palm wine from B. akeassii. Genotypic diversity of palm wine LAB and AAB not reported before is demonstrated and this constitutes valuable information for better understanding of the fermentation which can be used to improve the product quality and develop added value by-products. © 2012 The Society for Applied Microbiology.

Unravelling the contribution of lactic acid bacteria and acetic acid bacteria to cocoa fermentation using inoculated organisms.

PubMed

Ho, Van Thi Thuy; Fleet, Graham H; Zhao, Jian

2018-08-20

Cocoa beans (Theobroma cacao L.) are the raw material for chocolate production. Fermentation of the bean pulp by microorganisms is essential for developing the precursors of chocolate flavour. Currently, the cocoa fermentation is still conducted by an uncontrolled traditional process via a consortium of indigenous species of yeasts, lactic acid bacteria and acetic acid bacteria. Although the essential contribution of yeasts to the production of good quality beans and, typical chocolate character is generally agreed, the roles of lactic acid bacteria and acetic acid bacteria are less certain. The objective of this study was to investigate the contribution of LAB and AAB in cocoa bean fermentation by conducting small scale laboratory fermentations under aseptic conditions, inoculated with different groups of microorganisms previously isolated from spontaneous cocoa fermentations. The inoculation protocols were: (1) four yeasts Hanseniaspora guilliermondii, Pichia kudriavzevii, Kluyveromyces marxianus and Saccharomyces cerevisiae; (2) four yeasts plus the lactic acid bacteria Lactobacillus plantarum and Lactobacillus fermentum; (3) four yeasts plus the acetic acid bacteria Acetobacter pasteurianus and Gluconobacter frateuri and (4) four yeasts plus two lactic acid bacteria and two acetic acid bacteria. Only the inoculated species were detected in the microbiota of their respective fermentations. Beans from the inoculated fermentations showed no significant differences in colour, shell weights and concentrations of residual sugars, alcohols and esters (p>0.05), but they were slightly different in contents of lactic acid and acetic acid (p<0.05). All beans were fully brown and free of mould. Residual sugar levels were less than 2.6 mg/g while the shell contents and ethanol were in the range of 11-13.4% and 4.8-7 mg/g, respectively. Beans fermented in the presence of LAB contained higher levels of lactic acid (0.6-1.2 mg/g) whereas higher concentrations of acetic acid (1.8-2.2 mg/g) were detected in beans inoculated with AAB. Triangle and hedonic sensory evaluations of chocolates prepared from beans taken from the three fermentations showed no significant differences (p > 0.05). It was concluded that the growth of lactic acid bacteria and acetic acid bacteria may not be essential for the fermentation of cocoa beans. Copyright © 2018 Elsevier B.V. All rights reserved.

Identification of beer-spoilage bacteria using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry.

PubMed

Wieme, Anneleen D; Spitaels, Freek; Aerts, Maarten; De Bruyne, Katrien; Van Landschoot, Anita; Vandamme, Peter

2014-08-18

Applicability of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) for identification of beer-spoilage bacteria was examined. To achieve this, an extensive identification database was constructed comprising more than 4200 mass spectra, including biological and technical replicates derived from 273 acetic acid bacteria (AAB) and lactic acid bacteria (LAB), covering a total of 52 species, grown on at least three growth media. Sequence analysis of protein coding genes was used to verify aberrant MALDI-TOF MS identification results and confirmed the earlier misidentification of 34 AAB and LAB strains. In total, 348 isolates were collected from culture media inoculated with 14 spoiled beer and brewery samples. Peak-based numerical analysis of MALDI-TOF MS spectra allowed a straightforward species identification of 327 (94.0%) isolates. The remaining isolates clustered separately and were assigned through sequence analysis of protein coding genes either to species not known as beer-spoilage bacteria, and thus not present in the database, or to novel AAB species. An alternative, classifier-based approach for the identification of spoilage bacteria was evaluated by combining the identification results obtained through peak-based cluster analysis and sequence analysis of protein coding genes as a standard. In total, 263 out of 348 isolates (75.6%) were correctly identified at species level and 24 isolates (6.9%) were misidentified. In addition, the identification results of 50 isolates (14.4%) were considered unreliable, and 11 isolates (3.2%) could not be identified. The present study demonstrated that MALDI-TOF MS is well-suited for the rapid, high-throughput and accurate identification of bacteria isolated from spoiled beer and brewery samples, which makes the technique appropriate for routine microbial quality control in the brewing industry. Copyright © 2014 Elsevier B.V. All rights reserved.

Validation of the (GTG)(5)-rep-PCR fingerprinting technique for rapid classification and identification of acetic acid bacteria, with a focus on isolates from Ghanaian fermented cocoa beans.

PubMed

De Vuyst, Luc; Camu, Nicholas; De Winter, Tom; Vandemeulebroecke, Katrien; Van de Perre, Vincent; Vancanneyt, Marc; De Vos, Paul; Cleenwerck, Ilse

2008-06-30

Amplification of repetitive bacterial DNA elements through the polymerase chain reaction (rep-PCR fingerprinting) using the (GTG)(5) primer, referred to as (GTG)(5)-PCR fingerprinting, was found a promising genotypic tool for rapid and reliable speciation of acetic acid bacteria (AAB). The method was evaluated with 64 AAB reference strains, including 31 type strains, and 132 isolates from Ghanaian, fermented cocoa beans, and was validated with DNA:DNA hybridization data. Most reference strains, except for example all Acetobacter indonesiensis strains and Gluconacetobacter liquefaciens LMG 1509, grouped according to their species designation, indicating the usefulness of this technique for identification to the species level. Moreover, exclusive patterns were obtained for most strains, suggesting that the technique can also be used for characterization below species level or typing of AAB strains. The (GTG)(5)-PCR fingerprinting allowed us to differentiate four major clusters among the fermented cocoa bean isolates, namely A. pasteurianus (cluster I, 100 isolates), A. syzygii- or A. lovaniensis-like (cluster II, 23 isolates), and A. tropicalis-like (clusters III and IV containing 4 and 5 isolates, respectively). A. syzygii-like and A. tropicalis-like strains from cocoa bean fermentations were reported for the first time. Validation of the method and indications for reclassifications of AAB species and existence of new Acetobacter species were obtained through 16S rRNA sequencing analyses and DNA:DNA hybridizations. Reclassifications refer to A. aceti LMG 1531, Ga. xylinus LMG 1518, and Ga. xylinus subsp. sucrofermentans LMG 18788(T).

Evidence for foliar endophytic nitrogen fixation in a widely distributed subalpine conifer

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

Moyes, Andrew B.; Kueppers, Lara M.; Pett-Ridge, Jennifer

Coniferous forest nitrogen (N) budgets indicate unknown sources of N. A consistent association between limber pine ( Pinus flexilis) and potential N 2-fixing acetic acid bacteria (AAB) indicates that native foliar endophytes may supply subalpine forests with N.

Evidence for foliar endophytic nitrogen fixation in a widely distributed subalpine conifer

DOE PAGES

Moyes, Andrew B.; Kueppers, Lara M.; Pett-Ridge, Jennifer; ...

2016-02-01

Coniferous forest nitrogen (N) budgets indicate unknown sources of N. A consistent association between limber pine ( Pinus flexilis) and potential N 2-fixing acetic acid bacteria (AAB) indicates that native foliar endophytes may supply subalpine forests with N.

Spontaneous cocoa bean fermentation carried out in a novel-design stainless steel tank: influence on the dynamics of microbial populations and physical-chemical properties.

PubMed

de Melo Pereira, Gilberto Vinícius; Magalhães, Karina Teixeira; de Almeida, Euziclei Gonzaga; da Silva Coelho, Irene; Schwan, Rosane Freitas

2013-02-01

Spontaneous cocoa bean fermentations carried out in a novel-design 40-kg-capacity stainless steel tank (SST) was studied in parallel to traditional Brazilian methods of fermentation in wooden boxes (40-kg-capacity wooden boxes (WB1) and 600-kg-capacity wooden boxes (WB2)) using a multiphasic approach that entailed culture-dependent and -independent microbiological analyses of fermenting cocoa bean pulp samples and target metabolite analyses of both cocoa pulp and cotyledons. Both microbiological approaches revealed that the dominant species of major physiological roles were the same for fermentations in SST, relative to boxes. These species consisted of Saccharomyces cerevisiae and Hanseniaspora sp. in the yeast group; Lactobacillus fermentum and L. plantarum in the lactic acid bacteria (LAB) group; Acetobacter tropicalis belonging to the acetic acid bacteria (AAB) group; and Bacillus subtilis in the Bacillaceae family. A greater diversity of bacteria and non-Saccharomyces yeasts was observed in box fermentations. Additionally, a potentially novel AAB belonging to the genus Asaia was isolated during fermentation in WB1. Cluster analysis of the rRNA genes-PCR-DGGE profiles revealed a more complex picture of the box samples, indicating that bacterial and yeast ecology were fermentation-specific processes (wooden boxes vs. SST). The profile of carbohydrate consumption and fermentation products in the pulp and beans showed similar trends during both fermentation processes. However, the yeast-AAB-mediated conversion of carbohydrates into ethanol, and subsequent conversion of ethanol into acetic acid, was achieved with greater efficiency in SST, while temperatures were generally higher during fermentation in wooden boxes. With further refinements, the SST model may be useful in designing novel bioreactors for the optimisation of cocoa fermentation with starter cultures. Copyright © 2012 Elsevier B.V. All rights reserved.

Proteome analysis of Acetobacter pasteurianus during acetic acid fermentation.

PubMed

Andrés-Barrao, Cristina; Saad, Maged M; Chappuis, Marie-Louise; Boffa, Mauro; Perret, Xavier; Ortega Pérez, Ruben; Barja, François

2012-03-16

Acetic acid bacteria (AAB) are Gram-negative, strictly aerobic microorganisms that show a unique resistance to ethanol (EtOH) and acetic acid (AcH). Members of the Acetobacter and Gluconacetobacter genera are capable of transforming EtOH into AcH via the alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH) enzymes and are used for the industrial production of vinegar. Several mechanisms have been proposed to explain how AAB resist high concentrations of AcH, such as the assimilation of acetate through the tricarboxylic acid (TCA) cycle, the export of acetate by various transporters and modifications of the outer membrane. However, except for a few acetate-specific proteins, little is known about the global proteome responses to AcH. In this study, we used 2D-DIGE to compare the proteome of Acetobacter pasteurianus LMG 1262(T) when growing in glucose or ethanol and in the presence of acetic acid. Interesting protein spots were selected using the ANOVA p-value of 0.05 as threshold and 1.5-fold as the minimal level of differential expression, and a total of 53 proteins were successfully identified. Additionally, the size of AAB was reduced by approximately 30% in length as a consequence of the acidity. A modification in the membrane polysaccharides was also revealed by PATAg specific staining. Copyright © 2011 Elsevier B.V. All rights reserved.

Effects of Growth Medium on Matrix-Assisted Laser Desorption–Ionization Time of Flight Mass Spectra: a Case Study of Acetic Acid Bacteria

PubMed Central

Wieme, Anneleen D.; Spitaels, Freek; Aerts, Maarten; De Bruyne, Katrien; Van Landschoot, Anita

2014-01-01

The effect of the growth medium used on the matrix-assisted laser desorption ionization–time of flight (MALDI-TOF) mass spectra generated and its consequences for species and strain level differentiation of acetic acid bacteria (AAB) were determined by using a set of 25 strains. The strains were grown on five different culture media that yielded a total of more than 600 mass spectra, including technical and biological replicates. The results demonstrate that the culture medium can have a profound effect on the mass spectra of AAB as observed in the presence and varying signal intensities of peak classes, in particular when culture media do not sustain optimal growth. The observed growth medium effects do not disturb species level differentiation but strongly affect the potential for strain level differentiation. The data prove that a well-constructed and robust MALDI-TOF mass spectrometry identification database should comprise mass spectra of multiple reference strains per species grown on different culture media to facilitate species and strain level differentiation. PMID:24362425

Different temperatures select distinctive acetic acid bacteria species and promotes organic acids production during Kombucha tea fermentation.

PubMed

De Filippis, Francesca; Troise, Antonio Dario; Vitaglione, Paola; Ercolini, Danilo

2018-08-01

Kombucha is a traditional beverage produced by tea fermentation, carried out by a symbiotic consortium of bacteria and yeasts. Acetic Acid Bacteria (AAB) usually dominate the bacterial community of Kombucha, driving the fermentative process. The consumption of this beverage was often associated to beneficial effects for the health, due to its antioxidant and detoxifying properties. We characterized bacterial populations of Kombucha tea fermented at 20 or 30 °C by using culture-dependent and -independent methods and monitored the concentration of gluconic and glucuronic acids, as well as of total polyphenols. We found significant differences in the microbiota at the two temperatures. Moreover, different species of Gluconacetobacter were selected, leading to a differential abundance of gluconic and glucuronic acids. Copyright © 2018 Elsevier Ltd. All rights reserved.

Microbiological and physicochemical characterization of small-scale cocoa fermentations and screening of yeast and bacterial strains to develop a defined starter culture.

PubMed

Pereira, Gilberto Vinícius de Melo; Miguel, Maria Gabriela da Cruz Pedrozo; Ramos, Cíntia Lacerda; Schwan, Rosane Freitas

2012-08-01

Spontaneous cocoa bean fermentations performed under bench- and pilot-scale conditions were studied using an integrated microbiological approach with culture-dependent and culture-independent techniques, as well as analyses of target metabolites from both cocoa pulp and cotyledons. Both fermentation ecosystems reached equilibrium through a two-phase process, starting with the simultaneous growth of the yeasts (with Saccharomyces cerevisiae as the dominant species) and lactic acid bacteria (LAB) (Lactobacillus fermentum and Lactobacillus plantarum were the dominant species), which were gradually replaced by the acetic acid bacteria (AAB) (Acetobacter tropicalis was the dominant species). In both processes, a sequence of substrate consumption (sucrose, glucose, fructose, and citric acid) and metabolite production kinetics (ethanol, lactic acid, and acetic acid) similar to that of previous, larger-scale fermentation experiments was observed. The technological potential of yeast, LAB, and AAB isolates was evaluated using a polyphasic study that included the measurement of stress-tolerant growth and fermentation kinetic parameters in cocoa pulp media. Overall, strains L. fermentum UFLA CHBE8.12 (citric acid fermenting, lactic acid producing, and tolerant to heat, acid, lactic acid, and ethanol), S. cerevisiae UFLA CHYC7.04 (ethanol producing and tolerant to acid, heat, and ethanol), and Acetobacter tropicalis UFLA CHBE16.01 (ethanol and lactic acid oxidizing, acetic acid producing, and tolerant to acid, heat, acetic acid, and ethanol) were selected to form a cocktail starter culture that should lead to better-controlled and more-reliable cocoa bean fermentation processes.

Microbiological and Physicochemical Characterization of Small-Scale Cocoa Fermentations and Screening of Yeast and Bacterial Strains To Develop a Defined Starter Culture

PubMed Central

Pereira, Gilberto Vinícius de Melo; Miguel, Maria Gabriela da Cruz Pedrozo; Ramos, Cíntia Lacerda

2012-01-01

Spontaneous cocoa bean fermentations performed under bench- and pilot-scale conditions were studied using an integrated microbiological approach with culture-dependent and culture-independent techniques, as well as analyses of target metabolites from both cocoa pulp and cotyledons. Both fermentation ecosystems reached equilibrium through a two-phase process, starting with the simultaneous growth of the yeasts (with Saccharomyces cerevisiae as the dominant species) and lactic acid bacteria (LAB) (Lactobacillus fermentum and Lactobacillus plantarum were the dominant species), which were gradually replaced by the acetic acid bacteria (AAB) (Acetobacter tropicalis was the dominant species). In both processes, a sequence of substrate consumption (sucrose, glucose, fructose, and citric acid) and metabolite production kinetics (ethanol, lactic acid, and acetic acid) similar to that of previous, larger-scale fermentation experiments was observed. The technological potential of yeast, LAB, and AAB isolates was evaluated using a polyphasic study that included the measurement of stress-tolerant growth and fermentation kinetic parameters in cocoa pulp media. Overall, strains L. fermentum UFLA CHBE8.12 (citric acid fermenting, lactic acid producing, and tolerant to heat, acid, lactic acid, and ethanol), S. cerevisiae UFLA CHYC7.04 (ethanol producing and tolerant to acid, heat, and ethanol), and Acetobacter tropicalis UFLA CHBE16.01 (ethanol and lactic acid oxidizing, acetic acid producing, and tolerant to acid, heat, acetic acid, and ethanol) were selected to form a cocktail starter culture that should lead to better-controlled and more-reliable cocoa bean fermentation processes. PMID:22636007

Oxidation of metabolites highlights the microbial interactions and role of Acetobacter pasteurianus during cocoa bean fermentation.

PubMed

Moens, Frédéric; Lefeber, Timothy; De Vuyst, Luc

2014-03-01

Four cocoa-specific acetic acid bacterium (AAB) strains, namely, Acetobacter pasteurianus 386B, Acetobacter ghanensis LMG 23848(T), Acetobacter fabarum LMG 24244(T), and Acetobacter senegalensis 108B, were analyzed kinetically and metabolically during monoculture laboratory fermentations. A cocoa pulp simulation medium (CPSM) for AAB, containing ethanol, lactic acid, and mannitol, was used. All AAB strains differed in their ethanol and lactic acid oxidation kinetics, whereby only A. pasteurianus 386B performed a fast oxidation of ethanol and lactic acid into acetic acid and acetoin, respectively. Only A. pasteurianus 386B and A. ghanensis LMG 23848(T) oxidized mannitol into fructose. Coculture fermentations with A. pasteurianus 386B or A. ghanensis LMG 23848(T) and Lactobacillus fermentum 222 in CPSM for lactic acid bacteria (LAB) containing glucose, fructose, and citric acid revealed oxidation of lactic acid produced by the LAB strain into acetic acid and acetoin that was faster in the case of A. pasteurianus 386B. A triculture fermentation with Saccharomyces cerevisiae H5S5K23, L. fermentum 222, and A. pasteurianus 386B, using CPSM for LAB, showed oxidation of ethanol and lactic acid produced by the yeast and LAB strain, respectively, into acetic acid and acetoin. Hence, acetic acid and acetoin are the major end metabolites of cocoa bean fermentation. All data highlight that A. pasteurianus 386B displayed beneficial functional roles to be used as a starter culture, namely, a fast oxidation of ethanol and lactic acid, and that these metabolites play a key role as substrates for A. pasteurianus in its indispensable cross-feeding interactions with yeast and LAB during cocoa bean fermentation.

Oxidation of Metabolites Highlights the Microbial Interactions and Role of Acetobacter pasteurianus during Cocoa Bean Fermentation

PubMed Central

Moens, Frédéric; Lefeber, Timothy

2014-01-01

Four cocoa-specific acetic acid bacterium (AAB) strains, namely, Acetobacter pasteurianus 386B, Acetobacter ghanensis LMG 23848T, Acetobacter fabarum LMG 24244T, and Acetobacter senegalensis 108B, were analyzed kinetically and metabolically during monoculture laboratory fermentations. A cocoa pulp simulation medium (CPSM) for AAB, containing ethanol, lactic acid, and mannitol, was used. All AAB strains differed in their ethanol and lactic acid oxidation kinetics, whereby only A. pasteurianus 386B performed a fast oxidation of ethanol and lactic acid into acetic acid and acetoin, respectively. Only A. pasteurianus 386B and A. ghanensis LMG 23848T oxidized mannitol into fructose. Coculture fermentations with A. pasteurianus 386B or A. ghanensis LMG 23848T and Lactobacillus fermentum 222 in CPSM for lactic acid bacteria (LAB) containing glucose, fructose, and citric acid revealed oxidation of lactic acid produced by the LAB strain into acetic acid and acetoin that was faster in the case of A. pasteurianus 386B. A triculture fermentation with Saccharomyces cerevisiae H5S5K23, L. fermentum 222, and A. pasteurianus 386B, using CPSM for LAB, showed oxidation of ethanol and lactic acid produced by the yeast and LAB strain, respectively, into acetic acid and acetoin. Hence, acetic acid and acetoin are the major end metabolites of cocoa bean fermentation. All data highlight that A. pasteurianus 386B displayed beneficial functional roles to be used as a starter culture, namely, a fast oxidation of ethanol and lactic acid, and that these metabolites play a key role as substrates for A. pasteurianus in its indispensable cross-feeding interactions with yeast and LAB during cocoa bean fermentation. PMID:24413595

Effect of chitosan and SO2 on viability of Acetobacter strains in wine.

PubMed

Valera, Maria José; Sainz, Florencia; Mas, Albert; Torija, María Jesús

2017-04-04

Wine spoilage is an important concern for winemakers to preserve the quality of their final product and avoid contamination throughout the production process. The use of sulphur dioxide (SO 2 ) is highly recommended to prevent wine spoilage due to its antimicrobial activity. However, SO 2 has a limited effect on the viability of acetic acid bacteria (AAB). Currently, the use of SO 2 alternatives is favoured in order to reduce the use of chemicals and improve stabilization in winemaking. Chitosan is a biopolymer that is approved by the European authorities and the International Organization of Vine and Wine to be used as a fining agent and antimicrobial in wines. However, its effectiveness in AAB prevention has not been studied. Two strains of Acetobacter, adapted to high ethanol environments, were analysed in this study. Both chitosan and SO 2 effects were compared in artificially contaminated wines. Both molecules reduced the metabolic activity of both AAB strains. Although AAB populations were detected by culture independent techniques, their numbers were reduced with time, and their viability decreased following the application of both products, especially with chitosan. Copyright © 2017 Elsevier B.V. All rights reserved.

Impact of high initial concentrations of acetic acid and ethanol on acetification rate in an internal Venturi injector bioreactor.

PubMed

Krusong, W; Yaiyen, S; Pornpukdeewatana, S

2015-03-01

To evaluate the comparative impact of high initial concentrations of acetic acid (AAi ) and of ethanol (ETi ) on acetification rate (ETA). Acetic acid bacteria (AAB) were cultivated in a 100-l internal Venturi injector bioreactor. To quantify the oxygen availability, the 1.0 l min(-1) air inflow rate for the start-up phase (25 l) while 3·0 l min(-1) for the operational phase (75 l) achieved a high oxygen transfer coefficient (kL a). Changes in cell wall by TEM images and the remained ADH and ALDH activities confirmed the high acid tolerance ability of AAB. While ETAs using high AAi at 65 g l(-1) could be processed of 9.57 ± 0.19 g l(-1) day(-1) , which is just higher than 9.12 ± 0.12 g l(-1) day(-1) using high ETi at 55 g l(-1) . The average biotransformation yields were at 96.3 ± 0.1% and 94.4 ± 0.1% for high AAi and ETi , respectively. Results confirm that high oxygenation was generated in the bioreactor. Both high AAi and ETi were important in increasing ETA under stress 100 g l(-1) total concentration. High acid-tolerant AAB contains the high ADH and ALDH activities causing higher ETAs in HIA process. It is a competitive commercialized acetification process. © 2014 The Society for Applied Microbiology.

Hanseniaspora opuntiae, Saccharomyces cerevisiae, Lactobacillus fermentum, and Acetobacter pasteurianus predominate during well-performed Malaysian cocoa bean box fermentations, underlining the importance of these microbial species for a successful cocoa bean fermentation process.

PubMed

Papalexandratou, Zoi; Lefeber, Timothy; Bahrim, Bakhtiar; Lee, Ong Seng; Daniel, Heide-Marie; De Vuyst, Luc

2013-09-01

Two spontaneous Malaysian cocoa bean box fermentations (one farm, two plantation plots) were investigated. Physical parameters, microbial community dynamics, yeast and bacterial species diversity [mainly lactic acid bacteria (LAB) and acetic acid bacteria (AAB)], and metabolite kinetics were monitored, and chocolates were produced from the respective fermented dry cocoa beans. Similar microbial growth and metabolite profiles were obtained for the two fermentations. Low concentrations of citric acid were found in the fresh pulp, revealing low acidity of the raw material. The main end-products of the catabolism of the pulp substrates glucose, fructose, and citric acid by yeasts, LAB, and AAB were ethanol, lactic acid, acetic acid, and/or mannitol. Hanseniaspora opuntiae, Lactobacillus fermentum, and Acetobacter pasteurianus were the prevalent species of the two fermentations. Saccharomyces cerevisiae, Lactobacillus plantarum, Lactobacillus pentosus, and Acetobacter ghanensis were also found during the mid-phase of the fermentation processes. Leuconostoc pseudomesenteroides and Acetobacter senegalensis were among the prevailing species during the initial phase of the fermentations. Tatumella saanichensis and Enterobacter sp. were present in the beginning of the fermentations and they could be responsible for the degradation of citric acid and/or the production of gluconic acid and lactic acid, respectively. The presence of facultative heterofermentative LAB during the fermentations caused a high production of lactic acid. Finally, as these fermentations were carried out with high-quality raw material and were characterised by a restricted microbial species diversity, resulting in successfully fermented dry cocoa beans and good chocolates produced thereof, it is likely that the prevailing species H. opuntiae, S. cerevisiae, Lb. fermentum, and A. pasteurianus were responsible for it. Copyright © 2013 Elsevier Ltd. All rights reserved.

Production of extracellular fructans by Gluconobacter nephelii P1464.

PubMed

Semjonovs, P; Shakirova, L; Treimane, R; Shvirksts, K; Auzina, L; Cleenwerck, I; Zikmanis, P

2016-02-01

Bacterial extracellular fructans, known as levans, have potential applications in food, pharmaceutical and cosmetic industries and high fructan producing strains could contribute into the cost reduction and more extensive commercial usage of them. An acetic acid bacteria (AAB) isolate P1464 was obtained from the Microbial Strain Collection of Institute of Microbiology and Biotechnology, University of Latvia and identified as Gluconobacter nephelii by DNA-DNA hybridization and the formation of extracellular fructans by this strain was confirmed. Isolated extracellular fructose polymers were characterized using FT-IR spectroscopy and the structural features of fructan appeared as similar to the reference sample of bacterial levan. Molecular mass estimates showed that the isolated G. nephelii P1464 fructose polymer has a relatively small molecular weight (Mw 1122·939 ± 153·453 kDa) and a sizeable polydispersity (Mw/Mn = 21·57 ± 1·60), as compared with other AAB, which could promote their physiological activity, including the prebiotic effects. Obtained at different cultivation conditions characteristics of fructan production, including the biotechnological indices such as the productivity (Qp) and yield (Yp/s) ranging from 0·774 to 1·244 g l(-1)  h and from 0·181 to 0·436 g g(-1) , respectively, confirmed, that G. nephelii P1464 could be used as promising strain for commercial production of levan. Bacterial fructans, known as levans, have extensive options for practical usage, however, actually limited due to high production costs. Therefore, the searches for efficient producer strains should be an urgent task to reduce costs. This study is the first report on the formation of fructans by a novel strain of acetic acid bacteria (AAB) Gluconobacter nephelii P1464. Characteristics obtained at different cultivation conditions confirmed the operation of a competitive and perspective producer strain. Isolated extracellular fructans are characterized by a lower molecular weight as compared with other AAB which could promote their physiological activity, including the prebiotic effects. © 2015 The Society for Applied Microbiology.

The cocoa bean fermentation process: from ecosystem analysis to starter culture development.

PubMed

De Vuyst, L; Weckx, S

2016-07-01

Cocoa bean fermentation is still a spontaneous curing process to facilitate drying of nongerminating cocoa beans by pulp removal as well as to stimulate colour and flavour development of fermented dry cocoa beans. As it is carried out on farm, cocoa bean fermentation is subjected to various agricultural and operational practices and hence fermented dry cocoa beans of variable quality are obtained. Spontaneous cocoa bean fermentations carried out with care for approximate four days are characterized by a succession of particular microbial activities of three groups of micro-organisms, namely yeasts, lactic acid bacteria (LAB) and acetic acid bacteria (AAB), which results in well-fermented fully brown cocoa beans. This has been shown through a plethora of studies, often using a multiphasic experimental approach. Selected strains of several of the prevailing microbial species have been tested in appropriate cocoa pulp simulation media to unravel their functional roles and interactions as well as in small plastic vessels containing fresh cocoa pulp-bean mass to evaluate their capacity to dominate the cocoa bean fermentation process. Various starter cultures have been proposed for successful fermentation, encompassing both cocoa-derived and cocoa nonspecific strains of (hybrid) yeasts, LAB and AAB, some of which have been implemented on farms successfully. © 2016 The Society for Applied Microbiology.

Acetobacter strains isolated during the acetification of blueberry (Vaccinium corymbosum L.) wine.

PubMed

Hidalgo, C; García, D; Romero, J; Mas, A; Torija, M J; Mateo, E

2013-09-01

Highbush blueberries (Vaccinium corymbosum L.) are known to have positive health benefits. The production of blueberry vinegar is one method to preserve this seasonal fruit and allow extended consumption. In this study, blueberry wine acetification was performed with naturally occurring micro-organisms and with an inoculated Acetobacter cerevisiae strain. Acetifications were carried out in triplicate using the Schützenbach method. The successful spontaneous processes took up to 66% more time than the processes involving inoculation. The isolation of acetic acid bacteria (AAB) and the analysis of these AAB using molecular methods allowed the identification of the main genotypes responsible of the blueberry acetification. Although the Acet. cerevisiae strain was the predominant strain isolated from the inoculated process samples, Acetobacter pasteurianus was isolated from samples for both processes and was the only species present in the spontaneous acetification samples. To the best of our knowledge, this is the first report describing the identification and variability of AAB isolated during blueberry acetification. The isolated Acet. pasteurianus strains could be used for large-scale blueberry vinegar production or as a starter culture in studies of other vinegar production methods. © 2013 The Society for Applied Microbiology.

Efficacy of gaseous ozone to counteract postharvest table grape sour rot.

PubMed

Pinto, L; Caputo, L; Quintieri, L; de Candia, S; Baruzzi, F

2017-09-01

This work aims at studying the efficacy of low doses of gaseous ozone in postharvest control of the table grape sour rot, a disease generally attributed to a consortium of non-Saccharomyces yeasts (NSY) and acetic acid bacteria (AAB). Sour rot incidence of wounded berries, inoculated with 8 NSYstrains, or 7 AAB, or 56 yeast-bacterium associations, was monitored at 25 °C up to six days. Sour rot incidence in wounded berries inoculated with yeast-bacterium associations resulted higher than in berries inoculated with one single NSY or AAB strain. Among all NSY-AAB associations, the yeast-bacterium association composed of Candida zemplinina CBS 9494 (Cz) and Acetobacter syzygii LMG 21419 (As) showed the highest prevalence of sour rot; thus, after preliminary in vitro assays, this simplified As-Cz microbial consortium was inoculated in wounded berries that were stored at 4 °C for ten days under ozone (2.14 mg m -3 ) or in air. At the end of cold storage, no berries showed sour-rot symptoms although ozonation mainly affected As viable cell count. After additional 12 days at 25 °C, the sour rot index of inoculated As-Cz berries previously cold-stored under ozone or in air accounted for 22.6 ± 3.7% and 66.7 ± 4.5%, respectively. Molecular analyses of dominant AAB and NSY populations of both sound and rotten berries during post-refrigeration period revealed the appearance of new strains mainly belonging to Gluconobacter albidus and Hanseniaspora uvarum species, respectively. Cold ozonation resulted an effective approach to extend the shelf-life of table grapes also after cold storage. Copyright © 2017 Elsevier Ltd. All rights reserved.

A basic leucine zipper transcription factor, AabZIP1, connects abscisic acid signaling with artemisinin biosynthesis in Artemisia annua.

PubMed

Zhang, Fangyuan; Fu, Xueqing; Lv, Zongyou; Lu, Xu; Shen, Qian; Zhang, Ling; Zhu, Mengmeng; Wang, Guofeng; Sun, Xiaofen; Liao, Zhihua; Tang, Kexuan

2015-01-01

Artemisinin is a sesquiterpenoid especially synthesized in the Chinese herbal plant, Artemisia annua, which is widely used in the treatment of malaria. Artemisinin accumulation can be enhanced by exogenous abscisic acid (ABA) treatment. However, it is not known how ABA signaling regulates artemisinin biosynthesis. A global expression profile and phylogenetic analysis as well as the dual-LUC screening revealed that a basic leucine zipper family transcription factor from A. annua (namely AabZIP1) was involved in ABA signaling to regulate artemisinin biosynthesis. AabZIP1 had a higher expression level in the inflorescences than in other tissues; ABA treatment, drought, and salt stress strongly induced the expression of AabZIP1. Yeast one-hybrid assay and electrophoretic mobility shift assay (EMSA) showed that AabZIP1 bound to the ABA-responsive elements (ABRE) in the promoter regions of the amorpha-4,11-diene synthase (ADS) gene and CYP71AV1, which are two key structural genes of the artemisinin biosynthetic pathway. A mutagenesis assay showed that the C1 domain in the N-terminus of AabZIP1 was important for its transactivation activity. Furthermore, the activation of ADS and CYP71AV1 promoters by AabZIP1 was enhanced by ABA treatment in transient dual-LUC analysis. The AabZIP1 variant with C1 domain deletion lost the ability to activate ADS and CYP71AV1 promoters regardless of ABA treatment. Notably, overexpression of AabZIP1 in A. annua resulted in significantly increased accumulation of artemisinin. Our results indicate that ABA promotes artemisinin biosynthesis, likely through 1 activation of ADS and CYP71AV1 expression by AabZIP in A. annua. Meanwhile, our findings reveal the potential value of AabZIP1 in genetic engineering of artemisinin production. Copyright © 2015 The Author. Published by Elsevier Inc. All rights reserved.

Microbial community, and biochemical and physiological properties of Korean traditional black raspberry (Robus coreanus Miquel) vinegar.

PubMed

Song, Nho-Eul; Cho, Sung-Ho; Baik, Sang-Ho

2016-08-01

The aim of this study was to elucidate the changes in microbial community and biochemical and physiological properties of traditional Muju black raspberry (Robus coreanus Miquel) vinegar (TMBV) during fermentation by culture-independent methods. During vinegar fermentation, ethanol produced up to 120 g L(-1) until day 35, with continuously increasing yeast concentration to a total of log 7.6 CFU mL(-1) . After day 35, acetic acid bacteria (AAB) concentrations rose to log 5.8 CFU mL(-1) until day 144. Denaturing gradient gel electrophoresis analysis showed that Saccharomyces cerevisiae was detected until day 87 of the fermentation, at which point Acetobacter pasteurianus gradually took over as the dominant species. Total sugar was reduced to 6.6 °Brix and total acidity produced up to 44 g L(-1) . In this study, we established the physicochemical analysis and growth dynamics of yeast and AAB during alcoholic and acetic acid fermentation of black raspberry by a traditional method. Overall, S. cerevisiae and A. pasteurianus species appeared to dominate the TMBV fermentation. In conclusion, this study demonstrated a suitable fermentation system for TMBV by the static surface method. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.

Systematic review: Tumor-associated antigen autoantibodies and ovarian cancer early detection.

PubMed

Fortner, Renée Turzanski; Damms-Machado, Antje; Kaaks, Rudolf

2017-11-01

Tumor-associated autoantibodies (AAbs), produced as an immune response to tumor-associated antigens (TAAs), are a novel pathway of early detection markers. We conducted a systematic review on AAbs and ovarian cancer to summarize the diagnostic performance of individual AAbs and AAb panels. A total of 29 studies including 85 AAbs were included; 27 of the studies were conducted in prevalent cases and cancer-free controls and 2 investigations included pre-diagnosis samples. The majority of studies were hypothesis-driven, evaluating AAbs to target TAAs; 10 studies used screening approaches such as serological expression cloning (SEREX) and nucleic acid-programmable protein arrays (NAPPA). The highest sensitivities for individual AAbs were reported for RhoGDI-AAbs (89.5%) and TUBA1C-AAbs (89%); however, specificity levels were relatively low (80% and 75%, respectively). High sensitivities at high specificities were reported for HOXA7-AAbs for detection of moderately differentiated ovarian tumors (66.7% sensitivity at 100% specificity) and IL8-AAbs in stage I-II ovarian cancer (65.5% sensitivity at 98% specificity). A panel of 11 AAbs (ICAM3, CTAG2, p53, STYXL1, PVR, POMC, NUDT11, TRIM39, UHMK1, KSR1, and NXF3) provided 45% sensitivity at 98% specificity for serous ovarian cancer, when at least 2 AAbs were above a threshold of 95% specificity. Twelve of the AAbs identified in this review were investigated in more than one study. Data on diagnostic discrimination by tumor histology and stage at diagnosis are sparse. Limited data suggest select AAb markers improve diagnostic discrimination when combined with markers such as CA125 and HE4. AAbs for ovarian cancer early detection is an emerging area, and large-scale, prospective investigations considering histology and stage are required for discovery and validation. However, data to date suggests panels of AAbs may eventually reach sufficient diagnostic discrimination to allow earlier detection of disease as a complement to existing markers and transvaginal ultrasound. Copyright © 2017. Published by Elsevier Inc.

As(III) and As(V) removal from the aqueous phase via adsorption onto acid mine drainage sludge (AMDS) alginate beads and goethite alginate beads.

PubMed

Lee, Hongkyun; Kim, Dohyeong; Kim, Jongsik; Ji, Min-Kyu; Han, Young-Soo; Park, Young-Tae; Yun, Hyun-Shik; Choi, Jaeyoung

2015-07-15

Acid mine drainage sludge (AMDS) is a solid waste generated following the neutralization of acid mine drainage (AMD). This material entrapped in calcium alginate was investigated for the sorption of As(III) and As(V). Three different adsorbent materials were prepared: AMDS alginate beads (AABs), goethite alginate beads (GABs), and pure alginate beads. The effects of pH and the adsorption kinetics were investigated, and the adsorption isotherms were also evaluated. The optimum pH range using the AABs was determined to be within 2-10 for As(III) and 2-9 for As(V). Adsorption equilibrium data were evaluated using the Langmuir isotherm model, and the maximum adsorption capacity qmax was 18.25 and 4.97 mg g(-1) for As(III) on AAB and GAB, respectively, and 21.79 and 10.92 mg g(-1) for As(V) on AAB and GAB, respectively. The adsorption of As(III) and As(V) was observed to follow pseudo-second order kinetics. The As K-edge X-ray absorption near-edge structure (XANES) revealed that the adsorbed As(III) on the AABs was oxidized to As(V) via manganese oxide in the AMDS. Copyright © 2015 Elsevier B.V. All rights reserved.

Comparison of the bacterial species diversity of spontaneous cocoa bean fermentations carried out at selected farms in Ivory Coast and Brazil.

PubMed

Papalexandratou, Zoi; Camu, Nicholas; Falony, Gwen; De Vuyst, Luc

2011-08-01

To compare the spontaneous cocoa bean fermentation process carried out in different cocoa-producing regions, heap and box (one Ivorian farm) and box (two Brazilian farms) fermentations were carried out. All fermentations were studied through a multiphasic approach. In general, the temperature inside the fermenting mass increased throughout all fermentations and reached end-values of 42-48 °C. The main end-products of pulp carbohydrate catabolism were ethanol, lactic acid, acetic acid, and/or mannitol. In the case of the fermentations on the selected Ivorian farm, the species diversity of lactic acid bacteria (LAB) and acetic acid bacteria (AAB) was restricted. Lactobacillus fermentum and Leuconostoc pseudomesenteroides were the predominant LAB species, due to their ethanol and acid tolerance and citrate consumption. The levels of mannitol, ascribed to growth of L. fermentum, were fermentation-dependent. Also, enterobacterial species, such as Erwinia soli and Pantoea sp., were among the predominating microbiota during the early stages of both heap and box fermentations in Ivory Coast, which could be responsible for gluconic acid production. Consumption of gluconic acid at the initial phases of the Ivorian fermentations could be due to yeast growth. A wider microbial species diversity throughout the fermentation process was seen in the case of the box fermentations on the selected Brazilian farms, which differed, amongst other factors, regarding pod/bean selection on these farms as compared to fermentations on the selected Ivorian farm. This microbiota included Lactobacillus plantarum, Lactobacillus durianis, L. fermentum, Lactobacillus mali, Lactobacillus nagelii, L. pseudomesenteroides, and Pediococcus acidilactici, as well as Bacillus subtilis that was present at late fermentation, when the temperature inside the fermenting mass reached values higher than 50 °C. Moreover, AAB seemed to dominate the Brazilian box fermentations studied, explaining higher acetic acid concentrations in the pulp and the beans. To conclude, it turned out that the species diversity and community dynamics, influenced by local operational practices, in particular pod/bean selection, impact the quality of fermented cocoa beans. Copyright © 2011 Elsevier Ltd. All rights reserved.

Dietary supplementation with an amino acid blend enhances intestinal function in piglets.

PubMed

Yi, Dan; Li, Baocheng; Hou, Yongqing; Wang, Lei; Zhao, Di; Chen, Hongbo; Wu, Tao; Zhou, Ying; Ding, Binying; Wu, Guoyao

2018-05-16

The traditionally classified nutritionally non-essential amino acids are now known to be insufficiently synthesized for maximal growth and optimal health in piglets. This study determined the effects of dietary supplementation with an amino acid blend (AAB; glutamate:glutamine:glycine:arginine:N-acetylcysteine = 5:2:2:1:0.5) on piglet growth performance and intestinal functions. Sixteen piglets (24-day-old) were randomly assigned to a corn and soybean meal-based diet supplemented with 0.99% alanine (isonitrogenous control) or 1% AAB. On day 20 of the trial, blood and intestinal tissue samples were obtained from piglets. Compared with the control, AAB supplementation reduced (P < 0.05) diarrhoea incidence; plasma alanine aminotransferase and diamine oxidase activities; intestinal concentrations of hydrogen peroxide, malondialdehyde, and heat shock protein-70, and intestinal mRNA levels for interleukin-1β, interferon-γ, and chemokine (C-X-C motif) ligand-9; and the numbers of Enterobacterium family, Enterococcus genus and Clostridium coccoides in the colon digesta. Furthermore, AAB supplementation enhanced (P < 0.05): the plasma concentrations of serine, aspartate, glutamate, cysteine, tyrosine, phenylalanine, tryptophan, lysine, arginine, citrulline, ornithine, taurine, and γ-aminobutyric acid; intestinal villus height and surface area, villus height/crypt depth ratio, antioxidative enzyme activities, and mRNA levels for porcine β-defensin-1, sodium-independent amino acid transporters (b 0,+ AT and y + LAT1), aquaporin (AQP) 3, AQP8, AQP10, nuclear factor erythroid 2-related factor 2 and glutathione S-transferase omega-2, and protein abundances of AQP3, AQP4, claudin-1, occludin and myxovirus resistance 1; and the numbers of Bifidobacterium genus and Lactobacillus genus in the colon digesta. Collectively, these comprehensive results indicate that dietary AAB supplementation plays an important role in improving piglet growth and intestinal function.

Adsorption of Dyes in Studying the Surface Chemistry of Ultradispersed Diamond

NASA Astrophysics Data System (ADS)

Khokhlova, T. D.; Yunusova, G. R.; Lanin, S. N.

2018-05-01

The effect the surface chemistry of ultradispersed diamond (UDD) has on the adsorption of watersoluble dyes is considered. A comparison is made to adsorption on graphitized thermal carbon black (GTCB), which has a homogeneous and nonporous surface. The adsorption isotherms of dyes and the dependence of the adsorption on the pH of solutions are measured. It is found that UDD adsorbs acid (anionic) dyes—acid orange (AO) and acid anthraquinone blue (AAB)—but barely adsorbs a basic (cationic) dye, methylene blue (MB), because of the predominance of positively charged basic groups on the surface of UDD. The maximum adsorption of AO is much lower on UDD than on GTCB, while the maximum adsorption of AAB is similar for both surfaces. The adsorption of AO on UDD depends strongly on the pH of the solution, while the adsorption of AAB is independent of this parameter. It is suggested that the adsorption of AAB is determined not only by ionic and hydrophobic interactions but also by coordination interactions with impurity metal ions on a UDD surface. It is concluded that the adsorption of dyes characterizes the chemistry of a UDD surface with high sensitivity.

Whole-Genome Sequence Analysis of Bombella intestini LMG 28161T, a Novel Acetic Acid Bacterium Isolated from the Crop of a Red-Tailed Bumble Bee, Bombus lapidarius.

PubMed

Li, Leilei; Illeghems, Koen; Van Kerrebroeck, Simon; Borremans, Wim; Cleenwerck, Ilse; Smagghe, Guy; De Vuyst, Luc; Vandamme, Peter

2016-01-01

The whole-genome sequence of Bombella intestini LMG 28161T, an endosymbiotic acetic acid bacterium (AAB) occurring in bumble bees, was determined to investigate the molecular mechanisms underlying its metabolic capabilities. The draft genome sequence of B. intestini LMG 28161T was 2.02 Mb. Metabolic carbohydrate pathways were in agreement with the metabolite analyses of fermentation experiments and revealed its oxidative capacity towards sucrose, D-glucose, D-fructose and D-mannitol, but not ethanol and glycerol. The results of the fermentation experiments also demonstrated that the lack of effective aeration in small-scale carbohydrate consumption experiments may be responsible for the lack of reproducibility of such results in taxonomic studies of AAB. Finally, compared to the genome sequences of its nearest phylogenetic neighbor and of three other insect associated AAB strains, the B. intestini LMG 28161T genome lost 69 orthologs and included 89 unique genes. Although many of the latter were hypothetical they also included several type IV secretion system proteins, amino acid transporter/permeases and membrane proteins which might play a role in the interaction with the bumble bee host.

Hydrodesulfurization reactions of atmospheric gas oil over CoMo/alumina-aluminum borate catalysts

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

Chiuping Li; Jungchung Wu; Yuwen Chen

1993-08-01

A precipitation technique at constant pH value was used to prepare a series of alumina-aluminum borates (AABs) with various Al/B atomic ratios. These materials were used as the supports of Co-Mo catalysts. Hydrodesulfurization (HDS) of Kuwait atmospheric gas (AGO) oil was carried out over these presulfided catalysts in a bench-scale trickle bed reactor at 400 psi and 340 C. All CoMo/AAB catalysts are much more active than the conventional CoMo/Al[sub 2]O[sub 3] catalyst on HDS reactions. A correlation exists between the acidity and the HDS activity of the catalysts. The high activities of the CoMo/AAB catalysts can be rationalized onmore » the presence of boron. On one hand, it can increase the metal dispersions and hydrogenation capabilities. On the other hand, it can enhance the acidities and cracking abilities of the catalysts. The desulfurization data can be fitted with a pseudo-second-order rate equation. The activation energy for desulfurization is found to be 26 kcal/mol.« less

Autoantibodies of IgM and IgG classes show differences in recognition of multiple autoantigens in chronic obstructive pulmonary disease.

PubMed

Shindi, Reham; Almehairi, Amna; Negm, Ola H; Kalsheker, Noor; Gale, Nichola S; Shale, Dennis J; Harrison, Timothy W; Bolton, Charlotte E; John, Michelle; Todd, Ian; Tighe, Patrick J; Fairclough, Lucy C

2017-10-01

Autoimmunity occurs in chronic obstructive pulmonary disease (COPD). We describe an antigen microarray for detecting serum autoantibodies (AAbs) to determine how IgM, as well as IgG, AAbs distinguish patients with COPD from controls with a history of smoking without COPD. All COPD patients' sera contained elevated levels of AAbs to some of 30 autoantigens. There were significant differences in the autoantigenic specificities of IgM AAbs compared to IgG AAbs in the COPD sera: for example, AAbs to histone and scl-70 were mainly IgG, whereas AAbs to CENP-B and La/ssB were mainly IgM; by contrast, IgM and IgG AAbs to collagen-V were equally prevalent. Thus, a combination of IgM and IgG AAbs specific for multiple autoantigens are detected in all cases of COPD at a level at which all non-COPD controls are negative for AAbs. This highlights the importance of different classes of AAbs to a range of autoantigens in COPD. Copyright © 2017 Elsevier Inc. All rights reserved.

Improving the acetic acid tolerance and fermentation of Acetobacter pasteurianus by nucleotide excision repair protein UvrA.

PubMed

Zheng, Yu; Wang, Jing; Bai, Xiaolei; Chang, Yangang; Mou, Jun; Song, Jia; Wang, Min

2018-05-21

Acetic acid bacteria (AAB) are widely used in acetic acid fermentation due to their remarkable ability to oxidize ethanol and high tolerance against acetic acid. In Acetobacter pasteurianus, nucleotide excision repair protein UvrA was up-regulated 2.1 times by acetic acid when compared with that without acetic acid. To study the effects of UvrA on A. pasteurianus acetic acid tolerance, uvrA knockout strain AC2005-ΔuvrA, uvrA overexpression strain AC2005 (pMV24-uvrA), and the control strain AC2005 (pMV24), were constructed. One percent initial acetic acid was almost lethal to AC2005-ΔuvrA. However, the biomass of the UvrA overexpression strain was higher than that of the control under acetic acid concentrations. After 6% acetic acid shock for 20 and 40 min, the survival ratios of AC2005 (pMV24-uvrA) were 2 and 0.12%, respectively; however, they were 1.5 and 0.06% for the control strain AC2005 (pMV24). UvrA overexpression enhanced the acetification rate by 21.7% when compared with the control. The enzymes involved in ethanol oxidation and acetic acid tolerance were up-regulated during acetic acid fermentation due to the overexpression of UvrA. Therefore, in A. pasteurianus, UvrA could be induced by acetic acid and is related with the acetic acid tolerance by protecting the genome against acetic acid to ensure the protein expression and metabolism.

Direct and indirect climate controls predict heterogeneous early-mid 21st century wildfire burned area across western and boreal North America

PubMed Central

Falk, Donald A.; Westerling, Anthony L.; Swetnam, Thomas W.

2017-01-01

Predicting wildfire under future conditions is complicated by complex interrelated drivers operating across large spatial scales. Annual area burned (AAB) is a useful index of global wildfire activity. Current and antecedent seasonal climatic conditions, and the timing of snowpack melt, have been suggested as important drivers of AAB. As climate warms, seasonal climate and snowpack co-vary in intricate ways, influencing fire at continental and sub-continental scales. We used independent records of seasonal climate and snow cover duration (last date of permanent snowpack, LDPS) and cell-based Structural Equation Models (SEM) to separate direct (climatic) and indirect (snow cover) effects on relative changes in AAB under future climatic scenarios across western and boreal North America. To isolate seasonal climate variables with the greatest effect on AAB, we ran multiple regression models of log-transformed AAB on seasonal climate variables and LDPS. We used the results of multiple regressions to project future AAB using GCM ensemble climate variables and LDPS, and validated model predictions with recent AAB trends. Direct influences of spring and winter temperatures on AAB are larger and more widespread than the indirect effect mediated by changes in LDPS in most areas. Despite significant warming trends and reductions in snow cover duration, projected responses of AAB to early-mid 21st century are heterogeneous across the continent. Changes in AAB range from strongly increasing (one order of magnitude increases in AAB) to moderately decreasing (more than halving of baseline AAB). Annual wildfire area burned in coming decades is likely to be highly geographically heterogeneous, reflecting interacting regional and seasonal climate drivers of fire occurrence and spread. PMID:29244839

Direct and indirect climate controls predict heterogeneous early-mid 21st century wildfire burned area across western and boreal North America.

PubMed

Kitzberger, Thomas; Falk, Donald A; Westerling, Anthony L; Swetnam, Thomas W

2017-01-01

Predicting wildfire under future conditions is complicated by complex interrelated drivers operating across large spatial scales. Annual area burned (AAB) is a useful index of global wildfire activity. Current and antecedent seasonal climatic conditions, and the timing of snowpack melt, have been suggested as important drivers of AAB. As climate warms, seasonal climate and snowpack co-vary in intricate ways, influencing fire at continental and sub-continental scales. We used independent records of seasonal climate and snow cover duration (last date of permanent snowpack, LDPS) and cell-based Structural Equation Models (SEM) to separate direct (climatic) and indirect (snow cover) effects on relative changes in AAB under future climatic scenarios across western and boreal North America. To isolate seasonal climate variables with the greatest effect on AAB, we ran multiple regression models of log-transformed AAB on seasonal climate variables and LDPS. We used the results of multiple regressions to project future AAB using GCM ensemble climate variables and LDPS, and validated model predictions with recent AAB trends. Direct influences of spring and winter temperatures on AAB are larger and more widespread than the indirect effect mediated by changes in LDPS in most areas. Despite significant warming trends and reductions in snow cover duration, projected responses of AAB to early-mid 21st century are heterogeneous across the continent. Changes in AAB range from strongly increasing (one order of magnitude increases in AAB) to moderately decreasing (more than halving of baseline AAB). Annual wildfire area burned in coming decades is likely to be highly geographically heterogeneous, reflecting interacting regional and seasonal climate drivers of fire occurrence and spread.

Autoantibodies Specifically Against β1 Adrenergic Receptors and Adverse Clinical Outcome in Patients With Chronic Systolic Heart Failure in the β-Blocker Era: The Importance of Immunoglobulin G3 Subclass.

PubMed

Nagatomo, Yuji; Li, Daniel; Kirsop, Jennifer; Borowski, Alan; Thakur, Akanksha; Tang, W H Wilson

2016-06-01

To elucidate the prevalence and role of β1 adrenergic receptor autoantibodies (β1AR-AAb) belonging to the immunoglobulin (Ig)G3 subclass in patients with heart failure (HF) treated with β-adrenergic blockers. Several cardiac AAbs have been reported to be present in sera from patients with dilated cardiomyopathy and other etiologies. Among AAbs, those recognizing β1AR-AAbs show agonist-like effects, have detrimental effects on cardiomyocytes, and may induce persistent myocardial damage. We quantify total IgG and IgG3 subclass β1AR-AAb in subjects with chronic stable HF with long-term follow-up. In our study cohort of 121 subjects, non-IgG3-β1AR-AAb and IgG3-β1AR-AAb were found to be positive in 20 (17%) and 26 patients (21%), respectively. The positive rate of IgG3-β1AR-AAb was significantly higher for those with nonischemic compared with ischemic HF etiology (27% vs 8%, P = .01), but the positive rate for non-IgG3-β1AR-AAb was similar between the 2 groups (18% vs 16%, respectively, P = NS). There were no significant differences in clinical and echocardiographic measures among total β1AR-AAb negative, non-IgG3-β1AR-AAb positive, and IgG3-β1AR-AAb positive groups at baseline. During 2.2 ± 1.2 years of follow-up, we observed similar rates of the composite endpoint of all-cause mortality, cardiac transplantation, or hospitalization resulting from HF between total IgG-β1AR-AAb negative and positive patients. However, the composite endpoint events were significantly more common in the patients without than in those with IgG3-β1AR-AAb (P = .048, log-rank test). Presence of IgG3-β1AR-AAb, not total IgG, was associated with paradoxically more favorable outcomes in our cohort of patients with chronic systolic HF largely treated by β-blockers. Copyright © 2016 Elsevier Inc. All rights reserved.

Anti-Type VII Collagen Antibodies Are Identified in a Subpopulation of Bullous Pemphigoid Patients With Relapse

PubMed Central

Giusti, Delphine; Gatouillat, Grégory; Le Jan, Sébastien; Plée, Julie; Bernard, Philippe; Antonicelli, Frank; Pham, Bach-Nga

2018-01-01

Bullous pemphigoid (BP) is an autoimmune bullous skin disease characterized by anti-BP180 and anti-BP230 autoantibodies (AAbs). Mucous membrane involvement is an uncommon clinical feature of BP which may evoke epidermolysis bullosa acquisita, another skin autoimmune disease characterized by anti-type VII collagen AAbs. We therefore evaluated the presence of anti-type VII collagen AAbs in the serum of BP patients with and without mucosal lesions at time of diagnosis and under therapy. Anti-BP180, anti-BP230, and anti-type VII collagen AAbs were measured by ELISA in the serum of unselected patients fulfilling clinical and histo/immunopathological BP criteria at baseline (n = 71) and at time of relapse (n = 24). At baseline, anti-type VII collagen AAbs were detected in 2 out of 24 patients with BP presenting with mucosal involvement, but not in patients without mucosal lesions (n = 47). At the time of relapse, 10 out of 24 BP patients either displayed a significant induction or increase of concentrations of anti-type VII collagen AAbs (P < 0.01), independently of mucosal involvement. Those 10 relapsing BP patients were also characterized by a sustained high concentration of anti-BP180 AAb, whereas the serum anti-BP230 AAb concentrations did not vary in BP patients with relapse according to the presence of anti-type VII collagen AAbs. Thus, our study showed that anti-type VII collagen along with anti-BP180 AAbs detection stratified BP patients at time of relapse, illustrating a still dysregulated immune response that could reflect a potential epitope spreading mechanism in those BP patients. PMID:29619029

Neurotoxic lupus autoantibodies alter brain function through two distinct mechanisms

PubMed Central

Faust, Thomas W.; Chang, Eric H.; Kowal, Czeslawa; Berlin, RoseAnn; Gazaryan, Irina G.; Bertini, Eva; Zhang, Jie; Sanchez-Guerrero, Jorge; Fragoso-Loyo, Hilda E.; Volpe, Bruce T.; Diamond, Betty; Huerta, Patricio T.

2010-01-01

Damaging interactions between antibodies and brain antigenic targets may be responsible for an expanding range of neurological disorders. In the case of systemic lupus erythematosus (SLE), patients generate autoantibodies (AAbs) that frequently bind dsDNA. Although some symptoms of SLE may arise from direct reactivity to dsDNA, much of the AAb-mediated damage originates from cross-reactivity with other antigens. We have studied lupus AAbs that bind dsDNA and cross-react with the NR2A and NR2B subunits of the NMDA receptor (NMDAR). In adult mouse models, when the blood–brain barrier is compromised, these NMDAR-reactive AAbs access the brain and elicit neuronal death with ensuing cognitive dysfunction and emotional disturbance. The cellular mechanisms that underlie these deleterious effects remain incompletely understood. Here, we show that, at low concentration, the NMDAR-reactive AAbs are positive modulators of receptor function that increase the size of NMDAR-mediated excitatory postsynaptic potentials, whereas at high concentration, the AAbs promote excitotoxicity through enhanced mitochondrial permeability transition. Other synaptic receptors are completely unaffected by the AAbs. NMDAR activation is required for producing both the synaptic and the mitochondrial effects. Our study thus reveals the mechanisms by which NMDAR-reactive AAbs trigger graded cellular alterations, which are likely to be responsible for the transient and permanent neuropsychiatric symptoms observed in patients with SLE. Our study also provides a model in which local AAb concentration determines the exact nature of the cellular response. PMID:20921396

Differences in Physicochemical and Nutritional Properties of Breast and Thigh Meat from Crossbred Chickens, Commercial Broilers, and Spent Hens

PubMed Central

Chen, Yulian; Qiao, Yan; Xiao, Yu; Chen, Haochun; Zhao, Liang; Huang, Ming; Zhou, Guanghong

2016-01-01

The objective of this study was to compare the physicochemical and nutritional properties of breast and thigh meat from commercial Chinese crossbred chickens (817 Crossbred chicken, 817C), imported commercial broilers (Arbor Acres broiler, AAB), and commercial spent hens (Hyline Brown, HLB). The crossbred chickens, commercial broilers and spent hens were slaughtered at their typical market ages of 45 d, 40 d, and 560 d, respectively. The results revealed that several different characteristic features for the three breeds. The meat of the 817C was darker than that of the other two genotypes. The 817C were also characterized by higher protein, lower intramuscular fat, and better texture attributes (cooking loss, pressing loss and Warner-Bratzler shear force [WBSF]) compared with AAB and HLB. The meat of the spent hens (i.e. HLB) was higher in WBSF and total collagen content than meat of the crossbred chickens and imported broilers. Furthermore, correlation analysis and principal component analysis revealed that there was a clear relationship among physicochemical properties of chicken meats. With regard to nutritional properties, it was found that 817C and HLB exhibited higher contents of essential amino acids and essential/non-essential amino acid ratios. In addition, 817C were noted to have highest content of microelements whereas AAB have highest content of potassium. Besides, 817C birds had particularly higher proportions of desirable fatty acids, essential fatty acids, polyunsaturated/saturated and (18:0+18:1)/16:0 ratios. The present study also revealed that there were significant differences on breast meat and thigh meat for the physicochemical and nutritional properties, regardless of chicken breeds. In conclusion, meat of crossbred chickens has some unique features and exhibited more advantages over commercial broilers and spent hens. Therefore, the current investigation would provide valuable information for the chicken meat product processing, and influence the consumption of different chicken meat. PMID:26954114

Differences in Physicochemical and Nutritional Properties of Breast and Thigh Meat from Crossbred Chickens, Commercial Broilers, and Spent Hens.

PubMed

Chen, Yulian; Qiao, Yan; Xiao, Yu; Chen, Haochun; Zhao, Liang; Huang, Ming; Zhou, Guanghong

2016-06-01

The objective of this study was to compare the physicochemical and nutritional properties of breast and thigh meat from commercial Chinese crossbred chickens (817 Crossbred chicken, 817C), imported commercial broilers (Arbor Acres broiler, AAB), and commercial spent hens (Hyline Brown, HLB). The crossbred chickens, commercial broilers and spent hens were slaughtered at their typical market ages of 45 d, 40 d, and 560 d, respectively. The results revealed that several different characteristic features for the three breeds. The meat of the 817C was darker than that of the other two genotypes. The 817C were also characterized by higher protein, lower intramuscular fat, and better texture attributes (cooking loss, pressing loss and Warner-Bratzler shear force [WBSF]) compared with AAB and HLB. The meat of the spent hens (i.e. HLB) was higher in WBSF and total collagen content than meat of the crossbred chickens and imported broilers. Furthermore, correlation analysis and principal component analysis revealed that there was a clear relationship among physicochemical properties of chicken meats. With regard to nutritional properties, it was found that 817C and HLB exhibited higher contents of essential amino acids and essential/non-essential amino acid ratios. In addition, 817C were noted to have highest content of microelements whereas AAB have highest content of potassium. Besides, 817C birds had particularly higher proportions of desirable fatty acids, essential fatty acids, polyunsaturated/saturated and (18:0+18:1)/16:0 ratios. The present study also revealed that there were significant differences on breast meat and thigh meat for the physicochemical and nutritional properties, regardless of chicken breeds. In conclusion, meat of crossbred chickens has some unique features and exhibited more advantages over commercial broilers and spent hens. Therefore, the current investigation would provide valuable information for the chicken meat product processing, and influence the consumption of different chicken meat.

Ratios of regioisomers of minor acylglycerols less polar than triricinolein in castor oil estimated by mass spectrometry

USDA-ARS?s Scientific Manuscript database

We have recently reported the identification of forty new minor molecular species of acylglycerols containing hydroxy fatty acids less polar than triricinolein by electrospray ionization mass spectrometry of the lithium adducts. The ratios of regioisomers of triacylglycerols (ABC and AAB types) and ...

Effects of sucrose amendment on ammonia assimilation during sewage sludge composting.

PubMed

Meng, Liqiang; Li, Weiguang; Zhang, Shumei; Wu, Chuandong; Wang, Ke

2016-06-01

The aim of this study was to evaluate the laboratory-scale composting of sewage sludge and pumice mixtures that were amended with sucrose. The variation in temperature, pH, NH4(+)-N, ammonia emission, bacterial community, ammonia assimilating bacteria (AAB) populations and enzymatic activity related to ammonia assimilation were detected. The addition of sucrose increased the AAB population by 2.5-3.5 times, reduced ammonia emission by 24.7-31.1% compared with the control treatment, and promoted the growth of Bacillus and Wautersiella. The activities of glutamate dehydrogenase (GDH), glutamate synthase (GS) and glutamine synthetase (GOGAT), were enhanced by the addition of sucrose. GDH made a substantial contribution to ammonia assimilation when the ammonia concentration was high (⩾1.5g/kg) in the thermophilic phase. The GS/GOGAT cycle played an important role at low ammonia concentrations (⩽1.1g/kg) in the cooling phase. These results suggested that adding sucrose to sludge compost could promote ammonia assimilation and reduce ammonia emission. Copyright © 2016 Elsevier Ltd. All rights reserved.

Development of a Sequence-Characterized Amplified Region Marker-Targeted Quantitative PCR Assay for Strain-Specific Detection of Oenococcus oeni during Wine Malolactic Fermentation▿

PubMed Central

Solieri, Lisa; Giudici, Paolo

2010-01-01

Control over malolactic fermentation (MLF) is a difficult goal in winemaking and needs rapid methods to monitor Oenococcus oeni malolactic starters (MLS) in a stressful environment such as wine. In this study, we describe a novel quantitative PCR (QPCR) assay enabling the detection of an O. oeni strain during MLF without culturing. O. oeni strain LB221 was used as a model to develop a strain-specific sequence-characterized amplified region (SCAR) marker derived from a discriminatory OPA20-based randomly amplified polymorphic DNA (RAPD) band. The 5′ and 3′ flanking regions and the copy number of the SCAR marker were characterized using inverse PCR and Southern blotting, respectively. Primer pairs targeting the SCAR sequence enabled strain-specific detection without cross amplification of other O. oeni strains or wine species of lactic acid bacteria (LAB), acetic acid bacteria (AAB), and yeasts. The SCAR-QPCR assay was linear over a range of cell concentrations (7 log units) and detected as few as 2.2 × 102 CFU per ml of red wine with good quantification effectiveness, as shown by the correlation of QPCR and plate counting results. Therefore, the cultivation-independent monitoring of a single O. oeni strain in wine based on a SCAR marker represents a rapid and effective strain-specific approach. This strategy can be adopted to develop easy and rapid detection techniques for monitoring the implantation of inoculated O. oeni MLS on the indigenous LAB population, reducing the risk of unsuccessful MLF. PMID:20935116

Adult antisocial syndrome co-morbid with borderline personality disorder is associated with severe conduct disorder, substance dependence and violent antisociality.

PubMed

Freestone, Mark; Howard, Rick; Coid, Jeremy W; Ullrich, Simone

2013-01-01

This study tested the hypothesis that syndromal adult antisocial behaviour (AABS) co-morbid with borderline personality disorder (BPD) is a syndrome that emerges from severe conduct disorder (CD) in childhood and adolescence and is strongly associated, in adulthood, with both violence and substance dependence. In a sample of 8 580 community-resident adults screened for the presence of personality disorders, the following predictions arising from this hypothesis were tested: first, that those with AABS co-morbid with BPD would, in comparison with those showing AABS or BPD only, show a high level of antisocial outcomes, including violence; second, that adjusting for co-morbid alcohol dependence would attenuate group differences in many of the antisocial outcomes, and violence in particular; and third, that the AABS/BPD group would show both a high prevalence and a high severity of CD, and that adjusting for co-morbid CD would attenuate any association found between AABS/BPD co-morbidity and violence. Results confirmed these predictions, suggesting that AABS/BPD co-morbidity mediates the relationship between childhood CD and a predisposition to adult violence. The triad of AABS/BPD co-morbidity, alcohol dependence and severe CD is likely associated with the risk of criminal recidivism in offenders with personality disorder following release into the community. Copyright © 2012 John Wiley & Sons, Ltd.

Determination of optimum harvest maturity and physico-chemical quality of Rastali banana (Musa AAB Rastali) during fruit ripening.

PubMed

Kheng, Tee Yei; Ding, Phebe; Abdul Rahman, Nor Aini

2012-01-15

A series of physico-chemical quality (peel and pulp colours, pulp firmness, fruit pH, sugars and acids content, respiration rate and ethylene production) were conducted to study the optimum harvest periods (either week 11 or week 12 after emergence of the first hand) of Rastali banana (Musa AAB Rastali) based on the fruit quality during ripening. Rastali banana fruit exhibited a climacteric rise with the peaks of both CO(2) and ethylene production occurring simultaneously at day 3 after ripening was initiated and declined at day 5 when fruits entered the senescence stage. De-greening was observed in both of the harvesting weeks with peel turned from green to yellow, tissue softening, and fruits became more acidic and sweeter as ripening progressed. Sucrose, fructose and glucose were the main sugars found while malic, citric and succinic acids were the main organic acids found in the fruit. Rastali banana harvested at weeks 11 and 12 can be considered as commercial harvest period when the fruits have developed good organoleptic and quality attributes during ripening. However, Rastali banana fruit at more mature stage of harvest maturity taste slightly sweeter and softer with higher ethylene production which also means the fruits may undergo senescence faster than fruit harvested at week 11. Copyright © 2011 Society of Chemical Industry.

Ratios of regioisomers of minor acylglycerols less polar than triricinolein in castor oil estimated by mass spectrometry and the biosynthesis of tetraacylglycerols in castor

USDA-ARS?s Scientific Manuscript database

We have recently reported the identification of forty new minor molecular species of acylglycerols containing hydroxy fatty acids less polar than triricinolein by electrospray ionization mass spectrometry of the lithium adducts. The ratios of regioisomers of triacylglycerols (ABC and AAB types) and ...

Breast Reference Set Application: Karen Anderson-ASU (2014) — EDRN Public Portal

Cancer.gov

In order to increase the predictive value of tumor-specific antibodies for use as immunodiagnostics, our EDRN BDL has developed a novel protein microarray technology, termed Nucleic Acid Protein Programmable Array (NAPPA), which circumvents many of the limitations of traditional protein microarrays. NAPPA arrays are generated by printing full-length cDNAs encoding the target proteins at each feature of the array. The proteins are then transcribed and translated by a cell-free system and immobilized in situ using epitope tags fused to the proteins. Sera are added, and bound IgG is detected by standard secondary reagents. Using a sequential screening strategy to select AAb from 4,988 candidate tumor antigens, we have identified 28 potential AAb biomarkers for the early detection of breast cancer, and here we propose to evaluate these biomarkers using the EDRN Breast Cancer Reference Set.

Autofocusing Airy beam STED microscopy with long focal distance

NASA Astrophysics Data System (ADS)

Hu, Di; Liang, Yao; Chen, Yin; Chen, Zan Hui; Huang, Xu Guang

2017-12-01

Stimulated emission depletion (STED) is a very important technique in super-resolution microscopy. Until now, while autofocusing Airy beam (AAB) has been an attractive theme for both theoretical and applied researches, there are almost no report on AABs being used in STED microscopy. In this paper, we propose a novel STED microscopy based on AABs. A radially symmetric 3/2 phase plate is involved to simultaneously generate autofocusing excitation- and depletion-Airy beams. Remarkably, the AAB can auto-focus to a wavelength-scale spot with a long focal depth (several millimeters): on the contrary, the working distance of a conventional high numerical aperture (NA) objective is usually very short (about 200 μm). Our calculations indicate that the AAB based STED microscopy can achieve a super-resolution spot with FWHM of 58 nm while the focal length is 4.638 mm. Moreover, with properties of non-diffracting and self-healing, the Airy beam could enable a reduction of the scattering distortion induced by the specimens and has a great potential in imaging thick specimens.

Antibody response to actinomyces antigen and dental caries experience: implications for caries susceptibility.

PubMed

Levine, Martin; Owen, Willis L; Avery, Kevin T

2005-06-01

Fluoridated dentifrices reduce dental caries in subjects who perform effective oral hygiene. Actinomyces naeslundii increases in teeth-adherent microbial biofilms (plaques) in these subjects, and a well-characterized serum immunoglobulin G (IgG) antibody response (Actinomyces antibody [A-Ab]) is also increased. Other studies suggest that a serum IgG antibody response to streptococcal d-alanyl poly(glycerophosphate) (S-Ab) may indicate caries experience associated strongly with gingival health and exposure to fluoridated water. The aim of this study was to investigate relationships between A-Ab response, oral hygiene, S-Ab response, and caries experience. Measurements were made of A-Ab and S-Ab concentrations, caries experience (number of decayed, missing, and filled teeth [DMFT], number of teeth surfaces [DMFS], and number of decayed teeth needing treated [DT]), exposure to fluoridated water (Flu), mean clinical pocket depth (PD; in millimeters), and extent of plaque (PL) and gingival bleeding on probing (BOP). A-Ab concentration, the dependent variable in a multiple regression analysis, increased with S-Ab concentration and decreased with PL and DMFT adjusted for Flu (R(2) = 0.51, P < 0.002). Residual associations with age, DMFS, DT, and BOP were not significant. In addition, an elevated A-Ab response, defined from immunoprecipitation and immunoassay measurements, indicated a significant, 30% reduction in DMFT after adjustment for significant age and Flu covariance (analysis of variance with covariance F statistic = 10.6, P < 0.003; S-Ab response and interactions not significant). Thus, an elevated A-Ab response indicates less caries in subjects performing effective oral hygiene using fluoridated dentifrices. Conversely, a low A-Ab response is suggestive of decreased A. naeslundii binding to saliva-coated apatite and greater caries experience, as reported by others.

Quantitative analysis of triacylglycerol regioisomers in fats and oils using reversed-phase high-performance liquid chromatography and atmospheric pressure chemical ionization mass spectrometry.

PubMed

Fauconnot, Laëtitia; Hau, Jörg; Aeschlimann, Jean-Marc; Fay, Laurent-Bernard; Dionisi, Fabiola

2004-01-01

Positional distribution of fatty acyl chains of triacylglycerols (TGs) in vegetable oils and fats (palm oil, cocoa butter) and animal fats (beef, pork and chicken fats) was examined by reversed-phase high-performance liquid chromatography (RP-HPLC) coupled to atmospheric pressure chemical ionization using a quadrupole mass spectrometer. Quantification of regioisomers was achieved for TGs containing two different fatty acyl chains (palmitic (P), stearic (S), oleic (O), and/or linoleic (L)). For seven pairs of 'AAB/ABA'-type TGs, namely PPS/PSP, PPO/POP, SSO/SOS, POO/OPO, SOO/OSO, PPL/PLP and LLS/LSL, calibration curves were established on the basis of the difference in relative abundances of the fragment ions produced by preferred losses of the fatty acid from the 1/3-position compared to the 2-position. In practice the positional isomers AAB and ABA yield mass spectra showing a significant difference in relative abundance ratios of the ions AA(+) to AB(+). Statistical analysis of the validation data obtained from analysis of TG standards and spiked oils showed that, under repeatability conditions, least-squares regression can be used to establish calibration curves for all pairs. The regression models show linear behavior that allow the determination of the proportion of each regioisomer in an AAB/ABA pair, within a working range from 10 to 1000 microg/mL and a 95% confidence interval of +/-3% for three replicates. Copyright 2003 John Wiley & Sons, Ltd.

Flow Behavior in the Left Heart Ventricle Following Apico-Aortic Bypass Surgery

NASA Astrophysics Data System (ADS)

Shahriari, Shahrokh; Jeyhani, Morteza; Labrosse, Michel; Kadem, Lyes

2013-11-01

Apico-aortic bypass (AAB) surgery is an alternative for transcatheter aortic valve implantation (TAVI) to reduce left ventricle (LV) overload in patients with severe aortic stenosis (AS). It consists in connecting the apex of the LV to the descending thoracic aorta with a valved conduit. Postoperative flow assessments show that two thirds of the outflow is conducted from the LV apex to the conduit, while only one third crosses the native aortic valve. In this study, we performed high speed particle image velocimetry (PIV) measurements of flow pattern within an in vitro elastic model of LV in the presence of a very severe AS, before and after AAB. Results indicate that AAB effectively relieves the LV outflow obstruction; however, it also leads to abnormal ventricular flow patterns. Normal LV flow dynamics is characterized by an emerging mitral jet flow followed by the development of a vortical flow with velocities directed towards the aortic valve, while measurements in the presence of AAB show systolic flow bifurcating to the apical conduit and to the aortic valve outflow tract. This study provides the first insight into the LV flow structure after AAB including outflow jets and disturbed stagnation regions.

The relationship between BMI and insulin resistance and progression from single to multiple autoantibody positivity and type 1 diabetes among TrialNet Pathway to Prevention participants.

PubMed

Meah, Farah A; DiMeglio, Linda A; Greenbaum, Carla J; Blum, Janice S; Sosenko, Jay M; Pugliese, Alberto; Geyer, Susan; Xu, Ping; Evans-Molina, Carmella

2016-06-01

The incidence of type 1 diabetes is increasing at a rate of 3-5% per year. Genetics cannot fully account for this trend, suggesting an influence of environmental factors. The accelerator hypothesis proposes an effect of metabolic factors on type 1 diabetes risk. To test this in the TrialNet Pathway to Prevention (PTP) cohort, we analysed the influence of BMI, weight status and insulin resistance on progression from single to multiple islet autoantibodies (Aab) and progression from normoglycaemia to diabetes. HOMA1-IR was used to estimate insulin resistance in Aab-positive PTP participants. Cox proportional hazards models were used to evaluate the effects of BMI, BMI percentile (BMI%), weight status and HOMA1-IR on the progression of autoimmunity or the development of diabetes. Data from 1,310 single and 1,897 multiple Aab-positive PTP participants were included. We found no significant relationships between BMI, BMI%, weight status or HOMA1-IR and the progression from one to multiple Aabs. Similarly, among all Aab-positive participants, no significant relationships were found between BMI, weight status or HOMA1-IR and progression to diabetes. Diabetes risk was modestly increased with increasing BMI% among the entire cohort, in obese participants 13-20 years of age and with increasing HOMA1-IR in adult Aab-positive participants. Analysis of the accelerator hypothesis in the TrialNet PTP cohort does not suggest a broad influence of metabolic variables on diabetes risk. Efforts to identify other potentially modifiable environmental factors should continue.

Mortality risk from comorbidities independent of triple-negative breast cancer status: NCI-SEER-based cohort analysis.

PubMed

Swede, Helen; Sarwar, Amna; Magge, Anil; Braithwaite, Dejana; Cook, Linda S; Gregorio, David I; Jones, Beth A; R Hoag, Jessica; Gonsalves, Lou; L Salner, Andrew; Zarfos, Kristen; Andemariam, Biree; Stevens, Richard G; G Dugan, Alicia; Pensa, Mellisa; A Brockmeyer, Jessica

2016-05-01

A comparatively high prevalence of comorbidities among African-American/Blacks (AA/B) has been implicated in disparate survival in breast cancer. There is a scarcity of data, however, if this effect persists when accounting for the adverse triple-negative breast cancer (TNBC) subtype which occurs at threefold the rate in AA/B compared to white breast cancer patients. We reviewed charts of 214 white and 202 AA/B breast cancer patients in the NCI-SEER Connecticut Tumor Registry who were diagnosed in 2000-2007. We employed the Charlson Co-Morbidity Index (CCI), a weighted 17-item tool to predict risk of death in cancer populations. Cox survival analyses estimated hazard ratios (HRs) for all-cause mortality in relation to TNBC and CCI adjusting for clinicopathological factors. Among patients with SEER local stage, TNBC increased the risk of death (HR 2.18, 95 % CI 1.14-4.16), which was attenuated when the CCI score was added to the model (Adj. HR 1.50, 95 % CI 0.74-3.01). Conversely, the adverse impact of the CCI score persisted when controlling for TNBC (Adj. HR 1.49, 95 % CI 1.29-1.71; per one point increase). Similar patterns were observed in SEER regional stage, but estimated HRs were lower. AA/B patients with a CCI score of ≥3 had a significantly higher risk of death compared to AA/B patients without comorbidities (Adj. HR 5.65, 95 % CI 2.90-11.02). A lower and nonsignificant effect was observed for whites with a CCI of ≥3 (Adj. HR 1.90, 95 % CI 0.68-5.29). comorbidities at diagnosis increase risk of death independent of TNBC, and AA/B patients may be disproportionately at risk.

The relationship between BMI and insulin resistance and progression from single to multiple autoantibody positivity and type 1 diabetes among TrialNet Pathway to Prevention participants

PubMed Central

Meah, Farah A.; DiMeglio, Linda A.; Greenbaum, Carla J.; Blum, Janice S.; Sosenko, Jay M.; Pugliese, Alberto; Geyer, Susan; Xu, Ping; Evans-Molina, Carmella

2016-01-01

Aims/hypothesis The incidence of type 1 diabetes is increasing at a rate of 3–5% per year. Genetics cannot fully account for this trend, suggesting an influence of environmental factors. The accelerator hypothesis proposes an effect of metabolic factors on type 1 diabetes risk. To test this in the TrialNet Pathway to Prevention (PTP) cohort, we analysed the influence of BMI, weight status and insulin resistance on progression from single to multiple islet autoantibodies (Aab) and progression from normoglycaemia to diabetes. Methods HOMA1-IR was used to estimate insulin resistance in Aab-positive PTP participants. Cox proportional hazards models were used to evaluate the effects of BMI, BMI percentile (BMI%), weight status and HOMA1-IR on the progression of autoimmunity or the development of diabetes. Results Data from 1,310 single and 1,897 multiple Aab-positive PTP participants were included. We found no significant relationships between BMI, BMI%, weight status or HOMA1-IR and the progression from one to multiple Aabs. Similarly, among all Aab-positive participants, no significant relationships were found between BMI, weight status or HOMA1-IR and progression to diabetes. Diabetes risk was modestly increased with increasing BMI% among the entire cohort, in obese participants 13–20 years of age, and with increasing HOMA1-IR in adult Aab-positive participants. Conclusions/interpretation Analysis of the accelerator hypothesis in the TrialNet PTP cohort does not suggest a broad influence of metabolic variables on diabetes risk. Efforts to identify other potentially modifiable environmental factors should continue. PMID:26995649

Autoantibody presentation in drug-induced liver injury and idiopathic autoimmune hepatitis: the influence of human leucocyte antigen alleles.

PubMed

Stephens, Camilla; Castiella, Agustin; Gomez-Moreno, Eva M; Otazua, Pedro; López-Nevot, Miguel-Ángel; Zapata, Eva; Ortega-Alonso, Aida; Ruiz-Cabello, Francisco; Medina-Cáliz, Inmaculada; Robles-Díaz, Mercedes; Soriano, German; Roman, Eva; Hallal, Hacibe; Moreno-Planas, José M; Prieto, Martin; Andrade, Raúl J; Lucena, M Isabel

2016-09-01

Positive autoantibody (AAB) titres are commonly encountered in autoimmune hepatitis (AIH) and in a proportion of drug-induced liver injury (DILI) patients. The underlying mechanism for selective AAB occurrence in DILI is unknown, but could be associated with variations in immune-associated genes. Hence, we aimed to analyse human leucocyte antigen (HLA) allele compositions in DILI with positive (+) and negative (-) AAB titres and in AIH patients. High-resolution genotyping of HLA class I (A, B, C) and II (DRB1, DQB1) loci was performed on 207 DILI and 50 idiopathic AIH patients and compared with 885 healthy Spanish controls. Compared with controls, HLA-B*08:01 [44 vs. 9.7%, P=3.7E-13/corrected P-value (Pc)=1.0E-11], C*07:01 (46 vs. 24%, P=6.4E-04/Pc=0.012), DRB1*03:01 (58 vs. 21.5%, P=5.0E-09/Pc=1.0E-07) and DQB1*02:01 (56 vs. 22%, P=6.8E-08/Pc=9.0E-07) were significantly more frequent in AIH patients. The HLA-A*01:01 frequency was increased in the same population, but did not reach significance after Bonferroni's correction (34 vs. 19%, P=0.02/Pc=0.37). Fifty-eight of 207 DILI patients presented positive titres for at least one AAB (predominantly antinuclear antibody 76% and antismooth muscle antibody 28%). There was a tendency towards higher representation of DRB1*14:01 and DQB1*05:03 in DILI AAB+ compared with DILI AAB- (13.8 vs. 4.0%, P=0.02/Pc=0.5; 13.8 vs. 4.7%, P=0.04/Pc=0.5). The presence of HLA alleles B*08:01, C*07:01, DRB1*03:01, DQB1*02:01 and possibly A*01:01 enhances the risk of AIH (type 1) in Spanish patients. These alleles form part of the ancestral haplotype 8.1. HLA-DRB1*14:01 and DQB1*05:03 could potentially increase the risk of positive AAB (particularly antinuclear antibody) in Spanish DILI patients.

Autoantibodies in Serum of Systemic Scleroderma Patients: Peptide-Based Epitope Mapping Indicates Increased Binding to Cytoplasmic Domains of CXCR3.

PubMed

Recke, Andreas; Regensburger, Ann-Katrin; Weigold, Florian; Müller, Antje; Heidecke, Harald; Marschner, Gabriele; Hammers, Christoph M; Ludwig, Ralf J; Riemekasten, Gabriela

2018-01-01

Systemic sclerosis (SSc) is a severe chronic autoimmune disease with high morbidity and mortality. Sera of patients with SSc contain a large variety of autoantibody (aab) reactivities. Among these are functionally active aab that bind to G protein-coupled receptors (GPCR) such as C-X-C motif chemokine receptor 3 (CXCR3) and 4 (CXCR4). Aab binding to the N-terminal portion of these two GPCRs have been shown to be associated with slower disease progression in SSc, especially deterioration of lung function. Aabs binding to GPCRs exhibit functional activities by stimulating or inhibiting GPCR signaling. The specific functional activity of aabs crucially depends on the epitopes they bind to. To identify the location of important epitopes on CXCR3 recognized by aabs from SSc patients, we applied an array of 36 overlapping 18-20mer peptides covering the entire CXCR3 sequence, comparing epitope specificity of SSc patient sera ( N  = 32, with positive reactivity with CXCR3) to healthy controls ( N  = 30). Binding of SSc patient and control sera to these peptides was determined by ELISA. Using a Bayesian model approach, we found increased binding of SSc patient sera to peptides corresponding to intracellular epitopes within CXCR3, while the binding signal to extracellular portions of CXCR3 was found to be reduced. Experimentally determined epitopes showed a good correspondence to those predicted by the ABCpred tool. To verify these results and to translate them into a novel diagnostic ELISA, we combined the peptides that represent SSc-associated epitopes into a single ELISA and evaluated its potential to discriminate SSc patients ( N  = 31) from normal healthy controls ( N  = 47). This ELISA had a sensitivity of 0.61 and a specificity of 0.85. Our data reveals that SSc sera preferentially bind intracellular epitopes of CXCR3, while an extracellular epitope in the N-terminal domain that appears to be target of aabs in healthy individuals is not bound by SSc sera. Based upon our results, we could devise a novel ELISA concept that may be helpful for monitoring of SSc patients.

Autoantibodies in Serum of Systemic Scleroderma Patients: Peptide-Based Epitope Mapping Indicates Increased Binding to Cytoplasmic Domains of CXCR3

PubMed Central

Recke, Andreas; Regensburger, Ann-Katrin; Weigold, Florian; Müller, Antje; Heidecke, Harald; Marschner, Gabriele; Hammers, Christoph M.; Ludwig, Ralf J.; Riemekasten, Gabriela

2018-01-01

Systemic sclerosis (SSc) is a severe chronic autoimmune disease with high morbidity and mortality. Sera of patients with SSc contain a large variety of autoantibody (aab) reactivities. Among these are functionally active aab that bind to G protein-coupled receptors (GPCR) such as C-X-C motif chemokine receptor 3 (CXCR3) and 4 (CXCR4). Aab binding to the N-terminal portion of these two GPCRs have been shown to be associated with slower disease progression in SSc, especially deterioration of lung function. Aabs binding to GPCRs exhibit functional activities by stimulating or inhibiting GPCR signaling. The specific functional activity of aabs crucially depends on the epitopes they bind to. To identify the location of important epitopes on CXCR3 recognized by aabs from SSc patients, we applied an array of 36 overlapping 18-20mer peptides covering the entire CXCR3 sequence, comparing epitope specificity of SSc patient sera (N = 32, with positive reactivity with CXCR3) to healthy controls (N = 30). Binding of SSc patient and control sera to these peptides was determined by ELISA. Using a Bayesian model approach, we found increased binding of SSc patient sera to peptides corresponding to intracellular epitopes within CXCR3, while the binding signal to extracellular portions of CXCR3 was found to be reduced. Experimentally determined epitopes showed a good correspondence to those predicted by the ABCpred tool. To verify these results and to translate them into a novel diagnostic ELISA, we combined the peptides that represent SSc-associated epitopes into a single ELISA and evaluated its potential to discriminate SSc patients (N = 31) from normal healthy controls (N = 47). This ELISA had a sensitivity of 0.61 and a specificity of 0.85. Our data reveals that SSc sera preferentially bind intracellular epitopes of CXCR3, while an extracellular epitope in the N-terminal domain that appears to be target of aabs in healthy individuals is not bound by SSc sera. Based upon our results, we could devise a novel ELISA concept that may be helpful for monitoring of SSc patients. PMID:29623076

Improvement of banana cv. Rasthali (Silk, AAB) against Fusarium oxysporum f.sp. cubense (VCG 0124/5) through induced mutagenesis: Determination of LD50 specific to mutagen, explants, toxins and in vitro and in vivo screening for Fusarium wilt resistance.

PubMed

Saraswathi, M S; Kannan, G; Uma, S; Thangavelu, R; Backiyarani, S

2016-05-01

Shoot tips and in vitro grown proliferating buds of banana cv. Rasthali (Silk, AAB) were treated with various concentrations and durations of chemical mutagens viz., EMS, NaN3 and DES. LD50 for shoot tips based on 50% reduction in fresh weight was determined as 2% for 3 h, 0.02% for 5 h and 0.15% for 5 h, while for proliferating buds, they were 0.6% for 30 min, 0.01% for 2 h and 0.06% for 2 h for the mutagens EMS, NaN3 and DES, respectively. Subsequently, the mutated explants were screened in vitro against fusarium wilt using selection agents like fusaric acid and culture filtrate. LD50 for in vitro selection agents calculated based on 50% survival of explants was 0.050 mM and 7% for fusaric acid and culture filtrate, respectively and beyond which a rapid decline in growth was observed. This was followed by pot screening which led to the identification of three putative resistant mutants with an internal disease score of 1 (corm completely clean, no vascular discolouration). The putative mutants identified in the present study have also been mass multiplied in vitro.

On the Utilization of Pozzolanic Wastes as an Alternative Resource of Cement

PubMed Central

Karim, Md. Rezaul; Hossain, Md. Maruf; Khan, Mohammad Nabi Newaz; Zain, Muhammad Fauzi Mohd; Jamil, Maslina; Lai, Fook Chuan

2014-01-01

Recently, as a supplement of cement, the utilization of pozzolanic materials in cement and concrete manufacturing has increased significantly. This study investigates the scope to use pozzolanic wastes (slag, palm oil fuel ash and rice husk ash) as an alkali activated binder (AAB) that can be used as an alternative to cement. To activate these materials, sodium hydroxide solution was used at 1.0, 2.5 and 5.0 molar concentration added into the mortar, separately. The required solution was used to maintain the flow of mortar at 110% ± 5%. The consistency and setting time of the AAB-paste were determined. Mortar was tested for its flow, compressive strength, porosity, water absorption and thermal resistance (heating at 700 °C) and investigated by scanning electron microscopy. The experimental results reveal that AAB-mortar exhibits less flow than that of ordinary Portland cement (OPC). Surprisingly, AAB-mortars (with 2.5 molar solution) achieved a compressive strength of 34.3 MPa at 28 days, while OPC shows that of 43.9 MPa under the same conditions. Although water absorption and porosity of the AAB-mortar are slightly high, it shows excellent thermal resistance compared to OPC. Therefore, based on the test results, it can be concluded that in the presence of a chemical activator, the aforementioned pozzolans can be used as an alternative material for cement. PMID:28788277

On the Utilization of Pozzolanic Wastes as an Alternative Resource of Cement.

PubMed

Karim, Md Rezaul; Hossain, Md Maruf; Khan, Mohammad Nabi Newaz; Zain, Muhammad Fauzi Mohd; Jamil, Maslina; Lai, Fook Chuan

2014-12-05

Recently, as a supplement of cement, the utilization of pozzolanic materials in cement and concrete manufacturing has increased significantly. This study investigates the scope to use pozzolanic wastes (slag, palm oil fuel ash and rice husk ash) as an alkali activated binder (AAB) that can be used as an alternative to cement. To activate these materials, sodium hydroxide solution was used at 1.0, 2.5 and 5.0 molar concentration added into the mortar, separately. The required solution was used to maintain the flow of mortar at 110% ± 5%. The consistency and setting time of the AAB-paste were determined. Mortar was tested for its flow, compressive strength, porosity, water absorption and thermal resistance (heating at 700 °C) and investigated by scanning electron microscopy. The experimental results reveal that AAB-mortar exhibits less flow than that of ordinary Portland cement (OPC). Surprisingly, AAB-mortars (with 2.5 molar solution) achieved a compressive strength of 34.3 MPa at 28 days, while OPC shows that of 43.9 MPa under the same conditions. Although water absorption and porosity of the AAB-mortar are slightly high, it shows excellent thermal resistance compared to OPC. Therefore, based on the test results, it can be concluded that in the presence of a chemical activator, the aforementioned pozzolans can be used as an alternative material for cement.

ABA, AAB and ABC Renewal in Taste Aversion Learning

ERIC Educational Resources Information Center

Bernal-Gamboa, Rodolfo; Juarez, Yectivani; Gonzalez-Martin, Gabriela; Carranza, Rodrigo; Sanchez-Carrasco, Livia; Nieto, Javier

2012-01-01

Context renewal is identified when the conditioned response (CR) elicited by an extinguished conditioned stimulus (CS) reappears as a result of changing the contextual cues during the test. Two experiments were designed for testing contextual renewal in a conditioned taste aversion preparation. Experiment 1 assessed ABA and AAB context renewal,…

Gloeocapsopsis AAB1, an extremely desiccation-tolerant cyanobacterium isolated from the Atacama Desert.

PubMed

Azua-Bustos, Armando; Zúñiga, Jorge; Arenas-Fajardo, Cristián; Orellana, Marcelo; Salas, Loreto; Rafael, Vicuña

2014-01-01

The comprehensive study of microorganisms that evolved in the Atacama Desert, the driest and oldest on earth, may help to understand the key role of water for life. In this context, we previously characterized the microenvironment that allows colonization of the underside of quartzes in the Coastal Range of this desert by hypolithic microorganisms (Azua-Bustos et al. Microb Ecol 58:568-581, 2011). Now, we describe the biodiversity composition of these biofilms and the isolation from it of a new cyanobacterial strain. Based on morphologic and phylogenetic analyses, this isolate (AAB1) was classified as a new member of the Gloeocapsopsis genus. Physiological, morphological and molecular responses by isolate AAB1 show that this strain is extremely tolerant to desiccation. Our results also indicate that the isolate biosynthesizes sucrose and trehalose in response to this stressful condition. We identified two candidate genes involved in sucrose synthesis, namely sucrose 6-phosphate synthase and sucrose 6-phosphate phosphatase. Thus, the Gloeocapsopsis isolate AAB1 may represent a suitable model for understanding tolerance to low water availability.

Privacy-Preserving and Secure Sharing of PHR in the Cloud.

PubMed

Zhang, Leyou; Wu, Qing; Mu, Yi; Zhang, Jingxia

2016-12-01

As a new summarized record of an individual's medical data and information, Personal Health Record (PHR) can be accessible online. The owner can control fully his/her PHR files to be shared with different users such as doctors, clinic agents, and friends. However, in an open network environment like in the Cloud, these sensitive privacy information may be gotten by those unauthorized parties and users. In this paper, we consider how to achieve PHR data confidentiality and provide fine-grained access control of PHR files in the public Cloud based on Attribute Based Encryption(ABE). Differing from previous works, we also consider the privacy preserving of the receivers since the attributes of the receivers relate to their identity or medical information, which would make some sensitive data exposed to third services. Anonymous ABE(AABE) not only enforces the security of PHR of the owners but also preserves the privacy of the receivers. But a normal AABE with a single private key generation(PKG) center may not match a PHR system in the hierarchical architecture. Therefore, we discuss not only the construction of the PHR sharing system base on AABE but also how to construct the PHR sharing system based on the hierarchical AABE. The proposed schemes(especially based on hierarchical AABE) have many advantages over the available such as short public keys, constant-size private keys, which overcome the weaknesses in the existing works. In the standard model, the introduced schemes achieve compact security in the prime order groups.

Difference between beta1-adrenoceptor autoantibodies of human and animal origin-Limitations detecting beta1-adrenoceptor autoantibodies using peptide based ELISA technology.

PubMed

Wenzel, Katrin; Schulze-Rothe, Sarah; Müller, Johannes; Wallukat, Gerd; Haberland, Annekathrin

2018-01-01

Cell-based analytics for the detection of the beta1-adrenoceptor autoantibody (beta1-AAB) are functional, yet difficult to handle, and should be replaced by easily applicable, routine lab methods. Endeavors to develop solid-phase-based assays such as ELISA to exploit epitope moieties for trapping autoantibodies are ongoing. These solid-phase-based assays, however, are often unreliable when used with human patient material, in contrast to animal derived autoantibodies. We therefore tested an immunogen peptide-based ELISA for the detection of beta1-AAB, and compared commercially available goat antibodies against the 2nd extracellular loop of human beta1-adrenoceptor (ADRB1-AB) to autoantibodies enriched from patient material. The functionality of these autoantibodies was tested in a cell based assay for comparison and their structural appearance was investigated using 2D gel electrophoresis. The ELISA showed a limit of detection for ADRB1-AB of about 1.5 nmol antibody/L when spiked in human control serum and only about 25 nmol/L when spiked in species identical (goat) matrix material. When applied to samples of human origin, the ELISA failed to identify the specific beta1-AABs. A low concentration of beta1-AAB, together with structural inconsistency of the patient originated samples as seen from the 2D Gel appearance, might contribute to the failure of the peptide based ELISA technology to detect human beta1-AABs.

Mortality Risk from Co-Morbidities independent of Triple-Negative Breast Cancer Status: NCI SEER-based Cohort Analysis

PubMed Central

Swede, Helen; Sarwar, Amna; Magge, Anil; Braithwaite, Dejana; Cook, Linda S.; Gregorio, David I.; Jones, Beth A; Hoag, Jessica; Gonsalves, Lou; Salner, Andrew; Zarfos, Kristen; Andemariam, Biree; Stevens, Richard G; Dugan, Alicia; Pensa, Mellisa; Brockmeyer, Jessica

2017-01-01

Purpose A comparatively high prevalence of co-morbidities among African-American/Blacks (AA/B) has been implicated in disparate survival in breast cancer. There is a scarcity of data, however, if this effect persists when accounting for the adverse triple-negative breast cancer (TNBC) subtype which occurs at three-fold the rate in AA/B compared to white breast cancer patients. Methods We reviewed charts of 214 white and 202 AA/B breast cancer patients in the NCI-SEER Connecticut Tumor Registry who were diagnosed in 2000-07. We employed the Charlson Co-Morbidity Index (CCI), a weighted 17-item tool to predict risk of death in cancer populations. Cox Survival Analyses estimated hazard ratios (HR) for all-cause mortality in relation to TNBC and CCI adjusting for clinicopathological factors. Results Among patients with SEER-Local Stage, TNBC increased the risk of death (HR=2.18, 95% CI 1.14-4.16), which was attenuated when the CCI score was added to the model (Adj. HR=1.50, 95% CI 0.74-3.01). Conversely, the adverse impact of the CCI score persisted when controlling for TNBC (Adj. HR=1.49, 95% CI 1.29-1.71; per one point increase). Similar patterns were observed in SEER-Regional Stage but estimated HRs were lower. AA/B patients with a CCI score of ≥3 had a significantly higher risk of death compared to AA/B patients without comorbidities (Adj. HR=5.65, 95% CI 2.90-11.02). A lower and non-significant effect was observed for whites with a CCI of ≥3 (Adj. HR=1.90, 95% CI 0.68-5.29). Conclusions Co-morbidities at diagnosis increase risk of death independent of TNBC, and AA/B patients may be disproportionately at risk. PMID:27000206

Bacterial endophyte communities in the foliage of coast redwood and giant sequoia.

PubMed

Carrell, Alyssa A; Frank, Anna C

2015-01-01

The endophytic bacterial microbiome, with an emerging role in plant nutrient acquisition and stress tolerance, is much less studied in natural plant populations than in agricultural crops. In a previous study, we found consistent associations between trees in the pine family and acetic acid bacteria (AAB) occurring at high relative abundance inside their needles. Our objective here was to determine if that pattern may be general to conifers, or alternatively, is more likely restricted to pines or conifers growing in nutrient limited and exposed environments. We used 16S rRNA pyrosequencing to characterize the foliar endophyte communities of two conifers in the Cupressaceae family: Two coast redwood (CR; Sequoia sempervirens) populations and one giant sequoia (GS; Sequoiadendron giganteum) population were sampled. Similar to the pines, the endophyte communities of the giant trees were dominated by Proteobacteria, Firmicutes, Acidobacteria, and Actinobacteria. However, although some major operational taxonomic units (OTUs) occurred at a high relative abundance of 10-40% in multiple samples, no specific group of bacteria dominated the endophyte community to the extent previously observed in high-elevation pines. Several of the dominating bacterial groups in the CR and GS foliage (e.g., Bacillus, Burkholderia, Actinomycetes) are known for disease- and pest suppression, raising the possibility that the endophytic microbiome protects the giant trees against biotic stress. Many of the most common and abundant OTUs in our dataset were most similar to 16S rRNA sequences from bacteria found in lichens or arctic plants. For example, an OTU belonging to the uncultured Rhizobiales LAR1 lineage, which is commonly associated with lichens, was observed at high relative abundance in many of the CR samples. The taxa shared between the giant trees, arctic plants, and lichens may be part of a broadly defined endophyte microbiome common to temperate, boreal, and tundra ecosystems.

Bacterial endophyte communities in the foliage of coast redwood and giant sequoia

PubMed Central

Carrell, Alyssa A.; Frank, Anna C.

2015-01-01

The endophytic bacterial microbiome, with an emerging role in plant nutrient acquisition and stress tolerance, is much less studied in natural plant populations than in agricultural crops. In a previous study, we found consistent associations between trees in the pine family and acetic acid bacteria (AAB) occurring at high relative abundance inside their needles. Our objective here was to determine if that pattern may be general to conifers, or alternatively, is more likely restricted to pines or conifers growing in nutrient limited and exposed environments. We used 16S rRNA pyrosequencing to characterize the foliar endophyte communities of two conifers in the Cupressaceae family: Two coast redwood (CR; Sequoia sempervirens) populations and one giant sequoia (GS; Sequoiadendron giganteum) population were sampled. Similar to the pines, the endophyte communities of the giant trees were dominated by Proteobacteria, Firmicutes, Acidobacteria, and Actinobacteria. However, although some major operational taxonomic units (OTUs) occurred at a high relative abundance of 10–40% in multiple samples, no specific group of bacteria dominated the endophyte community to the extent previously observed in high-elevation pines. Several of the dominating bacterial groups in the CR and GS foliage (e.g., Bacillus, Burkholderia, Actinomycetes) are known for disease- and pest suppression, raising the possibility that the endophytic microbiome protects the giant trees against biotic stress. Many of the most common and abundant OTUs in our dataset were most similar to 16S rRNA sequences from bacteria found in lichens or arctic plants. For example, an OTU belonging to the uncultured Rhizobiales LAR1 lineage, which is commonly associated with lichens, was observed at high relative abundance in many of the CR samples. The taxa shared between the giant trees, arctic plants, and lichens may be part of a broadly defined endophyte microbiome common to temperate, boreal, and tundra ecosystems. PMID:26441933

Bacterial endophyte communities in the foliage of coast redwood and giant sequoia

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

Carrell, Alyssa A.; Frank, Anna C.

The endophytic bacterial microbiome, with an emerging role in plant nutrient acquisition and stress tolerance, is much less studied in natural plant populations than in agricultural crops. In a previous study, we found consistent associations between trees in the pine family and acetic acid bacteria (AAB) occurring at high relative abundance inside their needles. Our objective here was to determine if that pattern may be general to conifers, or alternatively, is more likely restricted to pines or conifers growing in nutrient limited and exposed environments. We used 16S rRNA pyrosequencing to characterize the foliar endophyte communities of two conifers inmore » the Cupressaceae family: Two coast redwood (CR; Sequoia sempervirens) populations and one giant sequoia (GS; Sequoiadendron giganteum) population were sampled. Similar to the pines, the endophyte communities of the giant trees were dominated by Proteobacteria, Firmicutes, Acidobacteria, and Actinobacteria. However, although some major operational taxonomic units (OTUs) occurred at a high relative abundance of 10–40% in multiple samples, no specific group of bacteria dominated the endophyte community to the extent previously observed in high-elevation pines. Several of the dominating bacterial groups in the CR and GS foliage (e.g., Bacillus, Burkholderia, Actinomycetes) are known for disease- and pest suppression, raising the possibility that the endophytic microbiome protects the giant trees against biotic stress. Many of the most common and abundant OTUs in our dataset were most similar to 16S rRNA sequences from bacteria found in lichens or arctic plants. For example, an OTU belonging to the uncultured Rhizobiales LAR1 lineage, which is commonly associated with lichens, was observed at high relative abundance in many of the CR samples. Lastly, the taxa shared between the giant trees, arctic plants, and lichens may be part of a broadly defined endophyte microbiome common to temperate, boreal, and tundra ecosystems.« less

Bacterial endophyte communities in the foliage of coast redwood and giant sequoia

DOE PAGES

Carrell, Alyssa A.; Frank, Anna C.

2015-09-22

The endophytic bacterial microbiome, with an emerging role in plant nutrient acquisition and stress tolerance, is much less studied in natural plant populations than in agricultural crops. In a previous study, we found consistent associations between trees in the pine family and acetic acid bacteria (AAB) occurring at high relative abundance inside their needles. Our objective here was to determine if that pattern may be general to conifers, or alternatively, is more likely restricted to pines or conifers growing in nutrient limited and exposed environments. We used 16S rRNA pyrosequencing to characterize the foliar endophyte communities of two conifers inmore » the Cupressaceae family: Two coast redwood (CR; Sequoia sempervirens) populations and one giant sequoia (GS; Sequoiadendron giganteum) population were sampled. Similar to the pines, the endophyte communities of the giant trees were dominated by Proteobacteria, Firmicutes, Acidobacteria, and Actinobacteria. However, although some major operational taxonomic units (OTUs) occurred at a high relative abundance of 10–40% in multiple samples, no specific group of bacteria dominated the endophyte community to the extent previously observed in high-elevation pines. Several of the dominating bacterial groups in the CR and GS foliage (e.g., Bacillus, Burkholderia, Actinomycetes) are known for disease- and pest suppression, raising the possibility that the endophytic microbiome protects the giant trees against biotic stress. Many of the most common and abundant OTUs in our dataset were most similar to 16S rRNA sequences from bacteria found in lichens or arctic plants. For example, an OTU belonging to the uncultured Rhizobiales LAR1 lineage, which is commonly associated with lichens, was observed at high relative abundance in many of the CR samples. Lastly, the taxa shared between the giant trees, arctic plants, and lichens may be part of a broadly defined endophyte microbiome common to temperate, boreal, and tundra ecosystems.« less

The dynamic and clinical significance of autoantibodies and immunoglobulins in liver transplant recipients.

PubMed

Stanca, Carmen M; Aloman, Costica; Fiel, Maria Isabel; Raja, Kaiser; Uskudar, Oguz; Florman, Sander; Schiano, Thomas D

2016-03-01

Little is known about autoantibody pattern in liver transplantation (LT). The aim of the study was to examine autoantibodies (AAB) and immunoglobulins in patients with end-stage liver disease before and after LT. Patients with LT who underwent post-LT biopsies between 10/2008 and 8/2011 were enrolled. AAB were assessed at the time of LT and liver biopsy. Demographics, serum immunoglobulins, AAB, and liver histology (explant, post-LT biopsies) were analyzed. Two hundred and twenty patients (M/F 143/77; age at LT 54 (19-73)) were included; AAB and immunoglobulins were evaluated in 76 patients. Length of follow-up from LT was 285 (30-1462) days. Sixty-one percent of patients had hepatitis C (HCV); 83% developed recurrent HCV. A significant decrease in IgG, IgA, IgM (p < 0.001 each), anticardiolipin antibodies IgG and IgM (p = 0.02), and beta-2 microglobulin (p = 0.004) was observed post-LT. HCV patients had higher IgG (p = 0.005), rheumatoid factor (p = 0.044) before LT; elevated IgM was associated with increased inflammation in the explant (p = 0.007). Lower IgG levels and antismooth muscle antibodies were present before LT in a higher percentage in patients who would develop recurrent HCV (p = 0.004, p = 0.077, respectively). In conclusion, AAB change significantly after LT and have a different pattern in HCV. Some immunological markers are associated with HCV recurrence and advanced inflammation on explant. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Bioremediation of a Large Chlorinated Solvent Plume, Dover AFB, DE

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

Bloom, Aleisa C

2015-01-01

Bioremediation of a Large Chlorinated Solvent Plume, Dover AFB, DE Aleisa Bloom, (Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA) Robert Lyon (bob.lyon@aecom.com), Laurie Stenberg, and Holly Brown (AECOM, Germantown, Maryland, USA) ABSTRACT: Past disposal practices at Dover Air Force Base (AFB), Delaware, created a large solvent plume called Area 6 (about 1 mile long, 2,000 feet wide, and 345 acres). The main contaminants are PCE, TCE, and their degradation products. The remedy is in-situ accelerated anaerobic bioremediation (AAB). AAB started in 2006 and is focusing on source areas and downgradient plume cores. Direct-push injections occurred in source areas wheremore » contamination is typically between 5 and 20 feet below ground surface. Lower concentration dissolved-phased contamination is present downgradient at 35 and 50 feet below ground surface. Here, permanent injection/extraction wells installed in transects perpendicular to the flow of groundwater are used to apply AAB. The AAB substrate is a mix of sodium lactate, emulsified vegetable oil, and nutrients. After eight years, dissolved contaminant mass within the main 80-acre treatment area has been reduced by over 98 percent. This successful application of AAB has stopped the flux of contaminants to the more distal portions of the plume. While more time is needed for effects to be seen in the distal plume, AAB injections will soon cease, and the remedy will transition to natural attenuation. INTRODUCTION Oak Ridge National Laboratory Environmental Science Division (ORNL) and AECOM (formerly URS Corporation) have successfully implemented in situ accelerated anaerobic bioremediation (AAB) to remediate chlorinated solvent contamination in a large, multi-sourced groundwater plume at Dover Air Force Base (AFB). AAB has resulted in significant reductions of dissolved phase chlorinated solvent concentrations. This plume, called Area 6, was originally over 1 mile in length and over 2,000 feet wide (Figure 1). It originated from at least four separate source areas that comingled in the subsurface to form the large plume. The major contaminants of concern (COCs) are tetrachloroethene (PCE), trichloroethene (TCE), and 1,1,1-trichloroethane (1,1,1-TCA), which were historically used for degreasing operations in the maintenance of aircraft and support vehicles. Relatively small areas of elevated PCE, TCE, and 1,1,1-TCA were delineated in the shallow portion of the water table aquifer by direct-push groundwater sampling. Focused direct-push AAB treatment occurred in March 2006 at these source areas (Figure 1). Downgradient of the these areas and deeper in the aquifer, AAB treatment was implemented using rows of extraction/injection wells oriented perpendicular to groundwater flow to create multiple reductive zones across the plume cores, defined as areas where more than 1,000 micrograms per liter (ug/L) total solvent concentrations were present. Initial indications of successful degradation were observed within 6 months of starting injections. FIGURE 1. Dover AFB Area 6 plume. This paper describes the AAB implementation and progress of remediation after 8 years of treatment and periodic groundwater monitoring. SITE LITHOLOGY Contamination at the site is limited to the surficial aquifer, which consists of 35 to 50 feet (ft) (11 to 15 meters [m]) of unconsolidated Pleistocene deposits of the Columbia Formation. The Columbia Formation consists of fine to coarse sand with silt and clay lenses and less common gravel lenses. Silts and silty sands are generally encountered to a depth of 10 to 12 ft (3.05 to 3.65 m) below ground surface (bgs) and grade to medium- and coarse-grained sands to a depth of 35 to 50 ft (11 to 15 m) bgs. There is a clay and silt unit (part of the Calvert Formation) below the surficial aquifer that acts as an aquitard to the downward migration of contaminants. The depth to the water table varies across the site but usually ranges from 8 to 15 ft (2.4 to 4.5 m) bgs in the treatment area. REMEDIAL APPROACH AND OPERATIONS Because the Columbia Aquifer is used as a source of potable water off base, the remedial goal is to restore the aquifer to usable condition, i.e., reduce all chemicals of concern to below drinking water maximum contaminant levels (MCLs). To achieve this goal, AAB was selected as the best remedial alternative to reduce the solvent contamination. Source areas with high solvent concentrations were present in the shallow portion of the aquifer. From the source areas, dissolved solvents migrated downgradient and deeper in the aquifer with the flow of groundwater. In the deeper portion of the aquifer, the individual plumes comingle to form the larger Area 6 Plume, which covers approximately 345 acres. Types of Substrate. Previous AAB pilot tests at Dover AFB used either sodium lactate or emulsified vegetable oil (EVO) as substrates to stimulate microbial growth. The best results were obtained with...« less

Effect of air-assisted backwashing on the performance of an anaerobic fixed-bed bioreactor that simultaneously removes nitrate and arsenic from drinking water sources.

PubMed

Upadhyaya, Giridhar; Clancy, Tara M; Snyder, Kathryn V; Brown, Jess; Hayes, Kim F; Raskin, Lutgarde

2012-03-15

Contaminant removal from drinking water sources under reducing conditions conducive for the growth of denitrifying, arsenate reducing, and sulfate reducing microbes using a fixed-bed bioreactor may require oxygen-free gas (e.g., N2 gas) during backwashing. However, the use of air-assisted backwashing has practical advantages, including simpler operation, improved safety, and lower cost. A study was conducted to evaluate whether replacing N2 gas with air during backwashing would impact performance in a nitrate and arsenic removing anaerobic bioreactor system that consisted of two biologically active carbon reactors in series. Gas-assisted backwashing, comprised of 2 min of gas injection to fluidize the bed and dislodge biomass and solid phase products, was performed in the first reactor (reactor A) every two days. The second reactor (reactor B) was subjected to N2 gas-assisted backwashing every 3-4 months. Complete removal of 50 mg/L NO3- was achieved in reactor A before and after the switch from N2-assisted backwashing (NAB) to air-assisted backwashing (AAB). Substantial sulfate removal was achieved with both backwashing strategies. Prolonged practice of AAB (more than two months), however, diminished sulfate reduction in reactor B somewhat. Arsenic removal in reactor A was impacted slightly by long-term use of AAB, but arsenic removals achieved by the entire system during NAB and AAB periods were not significantly different (p>0.05) and arsenic concentrations were reduced from approximately 200 μg/L to below 20 μg/L. These results indicate that AAB can be implemented in anaerobic nitrate and arsenic removal systems. Copyright © 2011 Elsevier Ltd. All rights reserved.

Reversing the sequence: reducing alcohol consumption by overcoming alcohol attentional bias.

PubMed

Fadardi, Javad Salehi; Cox, W Miles

2009-05-01

The aims of the research were to (a) compare the alcohol attentional bias (AAB) of social, hazardous, and harmful drinkers and (b) assess the effects of alcohol attention-control training on the AAB and alcohol consumption of hazardous and harmful drinkers. Participants were social drinkers (N=40), hazardous drinkers (N=89), and harmful drinkers (N=92). Paper-and-pencil measures were used to collect information about participants' socio-demographic characteristics, health status, motivational structure, drinking-related locus of control and situational self-confidence, readiness to change, affect, and alcohol consumption. Computerized classic, alcohol- and concerns-Stroop tests were administered. All participants were tested individually, with the order of tests counterbalanced across participants. After the baseline assessment, the hazardous and harmful drinkers were trained with the Alcohol Attention-Control Training Program (AACTP) for two and four sessions, respectively. Both samples completed a post-training assessment, and the harmful drinkers also completed 3-month follow-up. Results indicated that (a) the harmful drinkers had larger AAB than the hazardous and the social drinkers; (b) the attentional training reduced the hazardous and harmful drinkers' AAB; and (c) the harmful drinkers showed post-training reductions in alcohol consumption and improvements on the other drinking-related indices. The harmful drinkers' improvements were maintained at the 3-month follow-up.

From autoantibody research to standardized diagnostic assays in the management of human diseases - report of the 12th Dresden Symposium on Autoantibodies.

PubMed

Conrad, K; Andrade, L E C; Chan, E K L; Mahler, M; Meroni, P L; Pruijn, G J M; Steiner, G; Shoenfeld, Y

2016-07-01

Testing for autoantibodies (AABs) is becoming more and more relevant, not only for diagnosing autoimmune diseases (AIDs) but also for the differentiation of defined AID subtypes with different clinical manifestations, course and prognosis as well as the very early diagnosis for adequate management in the context of personalized medicine. A major challenge to improve diagnostic accuracy is to harmonize or even standardize AAB analyses. This review presents the results of the 12th Dresden Symposium on Autoantibodies that focused on several aspects of improving autoimmune diagnostics. Topics that are addressed include the International Consensus on ANA Patterns (ICAP) and the International Autoantibody Standardization (IAS) initiatives, the optimization of diagnostic algorithms, the description and evaluation of novel disease-specific AABs as well as the development and introduction of novel assays into routine diagnostics. This review also highlights important developments of recent years, most notably the improvement in diagnosing and predicting the course of rheumatoid arthritis, systemic sclerosis, idiopathic inflammatory myopathies, and of autoimmune neurological, gastrointestinal and liver diseases; the potential diagnostic role of anti-DFS70 antibodies and tumor-associated AABs. Furthermore, some hot topics in autoimmunity regarding disease pathogenesis and management are described. © The Author(s) 2016.

GLANDULAR TRICHOME-SPECIFIC WRKY 1 promotes artemisinin biosynthesis in Artemisia annua.

PubMed

Chen, Minghui; Yan, Tingxiang; Shen, Qian; Lu, Xu; Pan, Qifang; Huang, Youran; Tang, Yueli; Fu, Xueqing; Liu, Meng; Jiang, Weimin; Lv, Zongyou; Shi, Pu; Ma, Ya-Nan; Hao, Xiaolong; Zhang, Lida; Li, Ling; Tang, Kexuan

2017-04-01

Artemisinin is a type of sesquiterpene lactone well known as an antimalarial drug, and is specifically produced in glandular trichomes of Artemisia annua. However, the regulatory network for the artemisinin biosynthetic pathway remains poorly understood. Exploration of trichome-specific transcription factors would facilitate the elucidation of regulatory mechanism of artemisinin biosynthesis. The WRKY transcription factor GLANDULAR TRICHOME-SPECIFIC WRKY 1 (AaGSW1) was cloned and analysed in A. annua. AaGSW1 exhibited similar expression patterns to the trichome-specific genes of the artemisinin biosynthetic pathway and AP2/ERF transcription factor AaORA. A β-glucuronidase (GUS) staining assay further demonstrated that AaGSW1 is a glandular trichome-specific transcription factor. AaGSW1 positively regulates CYP71AV1 and AaORA expression by directly binding to the W-box motifs in their promoters. Overexpression of AaGSW1 in A. annua significantly improves artemisinin and dihydroartemisinic acid contents; moreover, AaGSW1 can be directly regulated by AaMYC2 and AabZIP1, which are positive regulators of jasmonate (JA)- and abscisic acid (ABA)-mediated artemisinin biosynthetic pathways, respectively. These results demonstrate that AaGSW1 is a glandular trichome-specific WRKY transcription factor and a positive regulator in the artemisinin biosynthetic pathway. Moreover, we propose that two trifurcate feed-forward pathways involving AaGSW1, CYP71AV1 and AaMYC2/AabZIP1 function in the JA/ABA response in A. annua. © 2016 The Authors. New Phytologist © 2016 New Phytologist Trust.

Insights into the factors responsible for curative effects of Aab-E-Shifa Spring Hasan Abdal (Pakistan)

NASA Astrophysics Data System (ADS)

ur Rahman, Sami; Bilal, Salma

2017-07-01

Springs are the gifts of nature on the earth as they contribute about eighty essential nutrients that are involved in more than 7000 enzymatic processes in the human body. European balneologists have recommended spring mineral waters for different therapeutic applications. In the present investigation, Aab- e- Shifa (Punjab Pakistan) spring water was analyzed due to its therapeutic behavior in the healing of various skin diseases via atomic absorption spectroscopy (AAS). It was found that besides other important minerals (Ca, Mg, K, and Na), the spring water contains the most significant antioxidant, i.e., Zn which is probably one of the major features of the curative behavior of Aab- e- Shifa. Other trace elements (Cr, Cd, Ni, Mn, Fe, and Cu) were also found to be present in the spring water under the permissible limits of various national and international organizations.

Rich magneto-absorption spectra of AAB-stacked trilayer graphene.

PubMed

Do, Thi-Nga; Shih, Po-Hsin; Chang, Cheng-Peng; Lin, Chiun-Yan; Lin, Ming-Fa

2016-06-29

A generalized tight-binding model is developed to investigate the feature-rich magneto-optical properties of AAB-stacked trilayer graphene. Three intragroup and six intergroup inter-Landau-level (inter-LL) optical excitations largely enrich magneto-absorption peaks. In general, the former are much higher than the latter, depending on the phases and amplitudes of LL wavefunctions. The absorption spectra exhibit single- or twin-peak structures which are determined by quantum modes, LL energy spectra and Fermion distribution. The splitting LLs, with different localization centers (2/6 and 4/6 positions in a unit cell), can generate very distinct absorption spectra. There exist extra single peaks because of LL anti-crossings. AAB, AAA, ABA, and ABC stackings considerably differ from one another in terms of the inter-LL category, frequency, intensity, and structure of absorption peaks. The main characteristics of LL wavefunctions and energy spectra and the Fermi-Dirac function are responsible for the configuration-enriched magneto-optical spectra.

Disentangling the relative contribution of parental antisociality and family discord to child disruptive disorders.

PubMed

Bornovalova, Marina A; Blazei, Ryan; Malone, Stephen H; McGue, Matt; Iacono, William G

2013-07-01

A number of familial risk factors for childhood disruptive disorders have been identified. However, many of these risk factors often co-occur with parental antisociality, which by itself may account for both the familial risk factors and the increased likelihood of offspring disruptive behavior disorders (DBDs). The current study aimed to examine the association of parenting behaviors, marital conflict, and divorce with child DBDs while accounting for (a) coparent parenting behaviors, and (b) parental adult antisocial behavior (AAB). A series of regressions tested the association between family-level variables (namely, parent-child relationship quality, parental willingness to use physical punishment, marital adjustment, and history of divorce) and DBDs (attention deficit hyperactivity disorder, conduct disorder, and oppositional defiant disorder) alone and after statistically adjusting for coparent variables and parental AAB. Results indicated that parents with AAB were more likely to engage in various forms of maladaptive parenting, to divorce, and to have conflictual marriages. Maladaptive parenting, marital conflict, and divorce were associated with heightened rates of child DBDs, and these associations persisted after adjusting for coparent parenting and parental AAB. Finally, the mother's parenting behaviors had a higher impact on child DBDs than the father's parenting behaviors. Thus, familial variables continue to have an effect on childhood DBDs even after accounting for confounding influences. These variables should be a focus of research on etiology and intervention.

Antisocial Behavioral Syndromes and Three-Year Quality of Life Outcomes in United States Adults

PubMed Central

Goldstein, Risë B.; Dawson, Deborah A.; Smith, Sharon M.; Grant, Bridget F.

2013-01-01

Objective To examine 3-year quality-of-life (QOL) outcomes among United States adults with Diagnostic and Statistical Manual of Mental Disorders – Fourth Edition (DSM-IV) antisocial personality disorder (ASPD), syndromal adult antisocial behavior without conduct disorder (CD) before age 15 (AABS, not a DSM-IV diagnosis), or no antisocial behavioral syndrome at baseline. Method Face-to-face interviews (n= 34,653). Psychiatric disorders were assessed using the Alcohol Use Disorder and Associated Disabilities Interview Schedule – DSM-IV Version. Health-related QOL was assessed using the Short-Form 12-Item Health Survey, version 2 (SF-12v2). Other outcomes included past-year Perceived Stress Scale-4 (PSS-4) scores, employment, receipt of Supplemental Security Income (SSI), welfare, and food stamps, and participation in social relationships. Results ASPD and AABS predicted poorer employment, financial dependency, social relationship, and physical health outcomes. Relationships of antisociality to SSI and food stamp receipt and physical health scales were modified by baseline age. Both antisocial syndromes predicted higher PSS-4, AABS predicted lower SF-12v2 Vitality, and ASPD predicted lower SF-12v2 Social Functioning scores in women. Conclusion Similar prediction of QOL by ASPD and AABS suggests limited utility of requiring CD before age 15 to diagnose ASPD. Findings underscore the need to improve prevention and treatment of antisocial syndromes. PMID:22375904

Disentangling the Relative Contribution of Parental Antisociality and Family Discord to Child Disruptive Disorders

PubMed Central

Bornovalova, Marina A.; Blazei, Ryan; Malone, Steve; McGue, Matt; Iacono, William G.

2012-01-01

A number of familial risk factors for childhood disruptive disorders have been identified. However, many of these risk factors often co-occur with parental antisociality, which by itself may account for both the familial risk factors and the increased likelihood of offspring disruptive behavior disorders (DBDs). The current study aimed to examine the association of parenting behaviors, marital conflict, and divorce with child DBDs while accounting for a) co-parent parenting behaviors, and b) parental adult antisocial behavior (AAB). A series of regressions tested the association between family-level variables (namely, parent-child relationship quality, parental willingness to use physical punishment, marital adjustment, and history of divorce) and DBDs (attention-deficit hyperactivity disorder, conduct disorder, and oppositional defiant disorder) alone and after statistically adjusting for co-parent variables and parental AAB. Results indicated that parents with AAB were more likely to engage in various forms of maladaptive parenting, to divorce, and to have conflictual marriages. Maladaptive parenting, marital conflict, and divorce were associated with heightened rates of child DBDs, and these associations persisted after adjusting for co-parent parenting and parental AAB. Finally, the mother’s parenting behaviors had a higher impact on child DBDs than the father’s parenting behaviors. Thus, familial variables continue to have an effect on childhood DBDs even after accounting for confounding influences. These variables should be a focus of research on etiology and intervention. PMID:22888991

Polarization and propagation characteristics of switchable first-order azimuthally asymmetric beam generated in dual-mode fiber.

PubMed

Khan, Saba N; Chatterjee, Sudip K; Chaudhuri, Partha Roy

2015-02-20

We report here the controlled generation of a linearly polarized first-order azimuthally asymmetric beam (F-AAB) in a dual-mode fiber (DMF) by appropriate superposition of selectively excited zeroth-order vector modes that are doughnut-shaped azimuthally symmetric beams (D-ASBs). We first demonstrate continually switching polarization mode structures having an identical two-lobe intensity profile (i.e., intra-F-AAB conversion). Then, under a distinct launching state, we generate mode structures progressively toggling between the doughnut-shaped profile and two-lobe pattern having dissimilar polarization orientations (i.e., F-AAB to D-ASB conversion). Interestingly, a decentralized elliptical Gaussian beam possessing homogenous spatial polarization is obtained by enhancing the contribution of the fundamental mode (HE₁₁/LP₀₁) in selectively excited F-AAB. A smoothly varying azimuth of the input beam in this situation resulted in redistribution of transverse energy procuring a unique and exciting unconventional two-grain T-polarized beam having mutually orthogonal state of polarization (SOP). All of the above three were achieved under a given set of launching conditions (tilt/offset) of a Gaussian mode (TEM₀₀) devised with changing SOP of the input beam. A strong modulation in the output beam characteristics was also observed with the variation in propagation distance (for a fixed input SOP) owing to the large difference in propagation constants of the participating modes (LP₀₁ and one of the F-AABs). Finally, this particular study led to a design for a low-cost highly sensitive strain measuring device based on tracking the centroid movement of the output intensity pattern. Each of our experimentally observed intensity/polarization distributions is theoretically mapped on a one-to-one basis considering a linear superposition of appropriately excited LP basis modes of the waveguide toward a complete understanding of the polarization and mode propagation in the dual-mode structure.

Anti-Ephrin Type-B Receptor 2 (EphB2) and Anti-Three Prime Histone mRNA EXonuclease 1 (THEX1) Autoantibodies in Scleroderma and Lupus

PubMed Central

Azzouz, Doua F.; Martin, Gabriel V.; Arnoux, Fanny; Balandraud, Nathalie; Martin, Thierry; Dubucquoi, Sylvain; Hachulla, Eric; Farge-Bancel, Dominique; Tiev, Kiet; Cabane, Jean; Bardin, Nathalie; Chiche, Laurent; Martin, Marielle; Caillet, Eléonore C.; Kanaan, Sami B.; Harlé, Jean Robert; Granel, Brigitte; Diot, Elisabeth; Roudier, Jean; Auger, Isabelle; Lambert, Nathalie C.

2016-01-01

In a pilot ProtoArray analysis, we identified 6 proteins out of 9483 recognized by autoantibodies (AAb) from patients with systemic sclerosis (SSc). We further investigated the 6 candidates by ELISA on hundreds of controls and patients, including patients with Systemic Lupus Erythematosus (SLE), known for high sera reactivity and overlapping AAb with SSc. Only 2 of the 6 candidates, Ephrin type-B receptor 2 (EphB2) and Three prime Histone mRNA EXonuclease 1 (THEX1), remained significantly recognized by sera samples from SSc compared to controls (healthy or with rheumatic diseases) with, respectively, 34% versus 14% (P = 2.10−4) and 60% versus 28% (P = 3.10−8). Above all, EphB2 and THEX1 revealed to be mainly recognized by SLE sera samples with respectively 56%, (P = 2.10−10) and 82% (P = 5.10−13). As anti-EphB2 and anti-THEX1 AAb were found in both diseases, an epitope mapping was realized on each protein to refine SSc and SLE diagnosis. A 15-mer peptide from EphB2 allowed to identify 35% of SLE sera samples (N = 48) versus only 5% of any other sera samples (N = 157), including SSc sera samples. AAb titers were significantly higher in SLE sera (P<0.0001) and correlated with disease activity (p<0.02). We could not find an epitope on EphB2 protein for SSc neither on THEX1 for SSc or SLE. We showed that patients with SSc or SLE have AAb against EphB2, a protein involved in angiogenesis, and THEX1, a 3’-5’ exoribonuclease involved in histone mRNA degradation. We have further identified a peptide from EphB2 as a specific and sensitive tool for SLE diagnosis. PMID:27617966

A method for determining regioisomer abundances of polyunsaturated triacylglycerols in omega-3 enriched fish oils using reversed-phase liquid chromatography and triple-stage mass spectrometry.

PubMed

Cubero Herrera, Lisandra; Ramaley, Louis; Potvin, Michael A; Melanson, Jeremy E

2013-08-15

Reversed-phase high performance liquid chromatography (RP-HPLC), followed by post-column addition of lithium salts and electrospray ionisation triple-stage mass spectrometry (ESI-MS(3)) of lithiated TAG adducts, is shown to provide a useful method for the positional analysis of triacylglycerols (TAGs) in fish oils containing eicosapentaenoic (EPA, 20:5) and docosahexaenoic acids (DHA, 22:6). One prominent fragmentation pathway in the ESI-MS(3) of these adduct ions involves the loss of a fatty acid from the sn-1/3 position in the first step followed by the loss of an α,β-unsaturated fatty acid from the sn-2 position in the second. Regioisomeric TAGs of the type ABA and AAB produced abundant product ions - [ABA+Li-RACOOH-R'BCHCHCOOH](+) and [AAB+Li-RACOOH-R'ACHCHCOOH](+) - the relative intensities of which were dependent on the position of acyl substituents. Standard solutions of TAGs containing different ratios of the regioisomeric pairs MME/MEM, PPE/PEP, PPD/PDP, EEP/EPE and DDP/DPD (M=14:0, P=16:0, E=20:5, D=22:6) were analysed by ESI-MS(3) with a quadrupole linear ion trap instrument. Methodology developed on the standards was applied to quantifying the relative isomeric abundances of EPA and DHA in several fish oil samples. DHA was preferentially located at the sn-2 position in both DHA-containing TAGs studied, while EPA was either observed at near equal levels in all positions, or predominantly at the sn-1 and -3 positions in some cases. The analysis protocol allows for quantification of the designated regioisomers in one simple, rapid chromatographic procedure using a single column and has the advantage of specificity over other methods for the positional analysis of TAGs, since it eliminates interferences associated with co-eluting TAGs of the same molecular weight that yield isobaric diacylglycerol-like product ions. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.

Antisocial Behavioral Syndromes and DSM-IV Drug Use Disorders in the United States: Results from the National Epidemiologic Survey on Alcohol and Related Conditions

PubMed Central

Goldstein, Risë B.; Compton, Wilson M.; Pulay, Attila J.; Ruan, W. June; Pickering, Roger P.; Stinson, Frederick S.; Grant, Bridget F.

2008-01-01

Background Antisocial behavioral syndromes, including antisocial personality disorder (ASPD), syndromal adult antisocial behavior (AABS) without conduct disorder (CD) before age 15, and CD without progression to ASPD (“CD only”) are highly comorbid with drug use disorders (DUDs). Among patients in DUD treatment, antisocial syndromes are associated with greater severity and poorer outcomes. Comparative data concerning associations of antisocial syndromes with clinical characteristics of DUDs among general population adults have not previously been available. This study describes associations of antisocial syndromes with clinical characteristics of lifetime Diagnostic and Statistical Manual – Version IV DUDs in the general U.S. adult population. Methods This report is based on the 2001–2002 National Epidemiologic Survey on Alcohol and Related Conditions (n=43,093, response rate=81%). Respondents (n=4,068) with lifetime DUDs were classified according to whether they met criteria for ASPD, AABS, “CD only,” or no antisocial syndrome. Associations of antisocial syndromes with clinical characteristics of DUDs were examined using logistic regression. Results Antisocial syndromes were significantly associated with the phenomenology of DUDs, particularly ASPD with the most severe clinical presentations. Associations with AABS were similar to those with ASPD; those with “CD only” were weak, inconsistent, and not statistically significant. Patterns of associations differed little between men and women. Conclusions Both ASPD and AABS, but not “CD only,” appear to identify greater clinical severity of DUDs among adults in the general U.S. population. PMID:17433571

Autoantibodies Associated With Connective Tissue Diseases: What Meaning for Clinicians?

PubMed Central

Didier, Kevin; Bolko, Loïs; Giusti, Delphine; Toquet, Segolene; Robbins, Ailsa; Antonicelli, Frank; Servettaz, Amelie

2018-01-01

Connective tissue diseases (CTDs) such as systemic lupus erythematosus, systemic sclerosis, myositis, Sjögren’s syndrome, and rheumatoid arthritis are systemic diseases which are often associated with a challenge in diagnosis. Autoantibodies (AAbs) can be detected in these diseases and help clinicians in their diagnosis. Actually, pathophysiology of these diseases is associated with the presence of antinuclear antibodies. In the last decades, many new antibodies were discovered, but their implication in pathogenesis of CTDs remains unclear. Furthermore, the classification of these AAbs is nowadays misused, as their targets can be localized outside of the nuclear compartment. Interestingly, in most cases, each antibody is associated with a specific phenotype in CTDs and therefore help in better defining either the disease subtypes or diseases activity and outcome. Because of recent progresses in their detection and in the comprehension of their pathogenesis implication in CTD-associated antibodies, clinicians should pay attention to the presence of these different AAbs to improve patient’s management. In this review, we propose to focus on the different phenotypes and features associated with each autoantibody used in clinical practice in those CTDs. PMID:29632529

Spontaneous 15N Nuclear Spin Hyperpolarization in Metal-Free Activation of Parahydrogen by Molecular Tweezers

PubMed Central

2018-01-01

The ability of frustrated Lewis pairs (FLPs) to activate H2 is of significant interest for metal-free catalysis. The activation of H2 is also the key element of parahydrogen-induced polarization (PHIP), one of the nuclear spin hyperpolarization techniques. It is demonstrated that o-phenylene-based ansa-aminoboranes (AABs) can produce 1H nuclear spin hyperpolarization through a reversible interaction with parahydrogen at ambient temperatures. Heteronuclei are useful in NMR and MRI as well because they have a broad chemical shift range and long relaxation times and may act as background-free labels. We report spontaneous formation of 15N hyperpolarization of the N–H site for a family of AABs. The process is efficient at the high magnetic field of an NMR magnet (7 T), and it provides up to 350-fold 15N signal enhancements. Different hyperpolarization effects are observed with various AAB structures and in a broad temperature range. Spontaneous hyperpolarization, albeit an order of magnitude weaker than that for 15N, was also observed for 11B nuclei. PMID:29401399

Antisocial Behavioral Syndromes and Past-Year Physical Health Among Adults in the United States: Results from the National Epidemiologic Survey on Alcohol and Related Conditions

PubMed Central

Goldstein, Risë B.; Dawson, Deborah A.; Chou, S. Patricia; Ruan, W. June; Saha, Tulshi D.; Pickering, Roger P.; Stinson, Frederick S.; Grant, Bridget F.

2010-01-01

Objective To describe associations of DSM-IV antisocial personality disorder (ASPD), conduct disorder without progression to ASPD (“CD only”), and syndromal antisocial behavior in adulthood without CD before age 15 (AABS, not a DSM-IV diagnosis) with past-year physical health status and hospital care utilization in the general U.S. adult population. Methods This report is based on the 2001-2002 National Epidemiologic Survey on Alcohol and Related Conditions (n=43,093, response rate=81%). Respondents were classified according to whether they met criteria for ASPD, AABS, “CD only,” or no antisocial syndrome. Associations of antisocial syndromes with physical health status and care utilization were examined using normal-theory and logistic regression. Results ASPD and AABS were significantly but modestly associated with total past-year medical conditions, coronary heart and gastrointestinal diseases, and numbers of inpatient hospitalizations, inpatient days, emergency department visits, and clinically significant injuries. ASPD was also associated with liver disease, arthritis, and lower scores on the Short Form-12 version 2 (SF-12v2) Physical Component, Role Physical, and Bodily Pain Scales. AABS was associated with noncoronary heart disease, lower scores on the SF-12v2 General Health and Vitality Scales, and, among men, arthritis. “CD only” was associated with single but not multiple inpatient hospitalizations, emergency department visits, and clinically significant injuries. Conclusions Estimates of burden related to antisocial behavioral syndromes need to consider associated physical health problems. Prevention and treatment guidelines for injuries and common chronic diseases may need to address comorbid antisociality, and interventions targeting antisociality may need to consider general health status, including prevention and management of injuries and chronic diseases. PMID:18348594

The Epidemiology of Antisocial Behavioral Syndromes in Adulthood: Results from the National Epidemiologic Survey on Alcohol and Related Conditions-III

PubMed Central

Goldstein, Risë B.; Chou, S. Patricia; Saha, Tulshi D.; Smith, Sharon M.; Jung, Jeesun; Zhang, Haitao; Pickering, Roger P.; Ruan, W. June; Huang, Boji; Grant, Bridget F.

2015-01-01

Objective To present current, nationally representative U.S. findings on prevalence, correlates, psychiatric comorbidity, disability and treatment of DSM-5 antisocial personality disorder (ASPD) and syndromal adult antisocial behavior without conduct disorder before age 15 (AABS). Method Face-to-face interviews with respondents (n=36,309) in the 2012-2013 National Epidemiologic Survey on Alcohol and Related Conditions–III. DSM-5 alcohol, nicotine, specific drug use disorders, and selected mood, anxiety, trauma-related, eating, and personality disorders were assessed using the Alcohol Use Disorder and Associated Disabilities Interview Schedule–5. Results Prevalences of ASPD and AABS were 4.3% and 20.3%, highest among male, white, Native American, younger, and unmarried respondents, those with high school or less education, lower incomes, and Western residence. Both antisocial syndromes were significantly associated with 12-month and lifetime substance use, dysthymia/persistent depressive, bipolar I, posttraumatic stress and borderline and schizotypal personality disorders (ORs=1.2-7.0). ASPD was additionally associated with 12-month agoraphobia and lifetime generalized anxiety disorder; AABS, with 12-month and lifetime major depressive and 12-month generalized anxiety disorders. Both were associated with significant disability (p<0.001 to 0.01). Most antisocial respondents were untreated. Conclusions One in 4 U.S. adults exhibits syndromal antisocial behavior, with similar sociodemographic and psychiatric correlates and disability regardless of whether onset occurred before age 15, illustrating the clinical and public health significance of both ASPD and AABS. In addition to laying groundwork for estimates of social and economic costs, and further etiologic and nosologic research, these findings highlight the urgency of effectively preventing and treating antisocial syndromes, including investigation of whether treatment for comorbidity hastens symptomatic remission and improves quality-of-life outcomes. PMID:27035627

B cells produce less IL-10, IL-6 and TNF-α in myasthenia gravis.

PubMed

Yilmaz, Vuslat; Oflazer, Piraye; Aysal, Fikret; Parman, Yeşim G; Direskeneli, Haner; Deymeer, Feza; Saruhan-Direskeneli, Güher

2015-06-01

B cells from myasthenia gravis (MG) patients with autoantibodies (Aab) against acetylcholine receptor (AChR), muscle-specific kinase (MuSK) or with no detectable Aab were investigated as cytokine producing cells in this study. B cells were evaluated for memory phenotypes and expressions of IL-10, IL-6 and IL-12A. Induced productions of IL-10, IL-6, IL-12p40, TNF-α and LT from isolated B cells in vitro were measured by immunoassays. MG patients receiving immunosuppressive treatment had higher proportions of memory B cells compared with healthy controls and untreated patients. With CD40 stimulation MG patients produced significantly lower levels of IL-10, IL-6. With CD40 and B cell receptor stimulation of B cells, TNF-α production also decreased in addition to these cytokines. The lower levels of these cytokine productions were not related to treatment. Our results confirm a disturbance of B cell subpopulations in MG subgroups on immunosuppressive treatment. B cell derived IL-10, IL-6 and TNF-α are down-regulated in MG, irrespective of different antibody productions. Ineffective cytokine production by B cells may be a susceptibility factor in dysregulation of autoimmune Aab production.

Investigating the Sources of Decadal-Scale Property Changes in Antarctic Bottom Water in the Southeast Indian Ocean (80-90°E)

NASA Astrophysics Data System (ADS)

Gottschalk, K.; Macdonald, A. M.

2016-12-01

A recognizable warming and freshening of Antarctic Bottom Water (AABW) throughout much of the Southern Ocean is one of the major findings of the international long-line hydrographic programs of 1990's and the 2000's. A recent GO-SHIP repeat of the I08S line in the southeast Indian Ocean in 2016 found continued, but weaker, AABW warming and significantly strong freshening in the Antarctic-Australian Basin (A-AB). It has been proposed that the 2010 B9b iceberg calving along the Adélie Land Coast may be linked to the sharp increase in A-AB AABW freshening. The present study seeks to affirm or challenge this hypothesis through a quantitative investigation into the origins of A-AB (i.e. I08S) bottom water. The investigation takes the form of an Extended Optimum MultiParameter mixing analysis (eOMP) to determine a) the contribution of individual formation regions to the bottom water seen at I08S, and b) how these contributions may have changed over the twenty years since the first occupation of the line. The initial investigation that used mean source water properties found Adélie Bottom Water (ADLBW) to be the dominant source of AABW in the A-AB. However, by calculating source water properties from times preceding the occupations of the I08S line (1994, 2007, 2016), it was determined that in both 1994 and 2007, Ross Sea Bottom Water (RSBW) was the dominant source of AABW (approx. 61 & 75 %, respectively) in the A-AB. This dominance shifted in 2016, to ADLBW composing approximately 44% of AABW. This result suggests that it is feasible that the B9b calving that impacted ADLBW in the formation region is, at least, partially responsible for the changes seen at I08S. Nevertheless, given that there are significant contributions from both RSBW and Weddell Sea Bottom Water, it seems unlikely that this single alteration of ADLBW is the sole driver of the observed freshening. Further investigation seeks to determine the sensitivity of the solution to particular source water definitions and to the specific property budgets used to constrain the system.

Dietary fibre components and pectin chemical features of peels during ripening in banana and plantain varieties.

PubMed

Happi Emaga, Thomas; Robert, Christelle; Ronkart, Sébastien N; Wathelet, Bernard; Paquot, Michel

2008-07-01

The effects of the ripeness stage of banana (Musa AAA) and plantain (Musa AAB) peels on neutral detergent fibre, acid detergent fibre, cellulose, hemicelluloses, lignin, pectin contents, and pectin chemical features were studied. Plantain peels contained a higher amount of lignin but had a lower hemicellulose content than banana peels. A sequential extraction of pectins showed that acid extraction was the most efficient to isolate banana peel pectins, whereas an ammonium oxalate extraction was more appropriate for plantain peels. In all the stages of maturation, the pectin content in banana peels was higher compared to plantain peels. Moreover, the galacturonic acid and methoxy group contents in banana peels were higher than in plantain peels. The average molecular weights of the extracted pectins were in the range of 132.6-573.8 kDa and were not dependant on peel variety, while the stage of maturation did not affect the dietary fibre yields and the composition in pectic polysaccharides in a consistent manner. This study has showed that banana peels are a potential source of dietary fibres and pectins.

The effect of lactic acid bacteria on cocoa bean fermentation.

PubMed

Ho, Van Thi Thuy; Zhao, Jian; Fleet, Graham

2015-07-16

Cocoa beans (Theobroma cacao L.) are the raw material for chocolate production. Fermentation of cocoa pulp by microorganisms is crucial for developing chocolate flavor precursors. Yeasts conduct an alcoholic fermentation within the bean pulp that is essential for the production of good quality beans, giving typical chocolate characters. However, the roles of bacteria such as lactic acid bacteria and acetic acid bacteria in contributing to the quality of cocoa bean and chocolate are not fully understood. Using controlled laboratory fermentations, this study investigated the contribution of lactic acid bacteria to cocoa bean fermentation. Cocoa beans were fermented under conditions where the growth of lactic acid bacteria was restricted by the use of nisin and lysozyme. The resultant microbial ecology, chemistry and chocolate quality of beans from these fermentations were compared with those of indigenous (control) fermentations. The yeasts Hanseniaspora guilliermondii, Pichia kudriavzevii, Kluyveromyces marxianus and Saccharomyces cerevisiae, the lactic acid bacteria Lactobacillus plantarum, Lactobacillus pentosus and Lactobacillus fermentum and the acetic acid bacteria Acetobacter pasteurianus and Gluconobacter frateurii were the major species found in control fermentations. In fermentations with the presence of nisin and lysozyme, the same species of yeasts and acetic acid bacteria grew but the growth of lactic acid bacteria was prevented or restricted. These beans underwent characteristic alcoholic fermentation where the utilization of sugars and the production of ethanol, organic acids and volatile compounds in the bean pulp and nibs were similar for beans fermented in the presence of lactic acid bacteria. Lactic acid was produced during both fermentations but more so when lactic acid bacteria grew. Beans fermented in the presence or absence of lactic acid bacteria were fully fermented, had similar shell weights and gave acceptable chocolates with no differences in sensory rankings. It was concluded that lactic acid bacteria may not be necessary for successful cocoa fermentation. Copyright © 2015. Published by Elsevier B.V.

Synthesis and physico-chemical characterization of modified starches from banana (Musa AAB) and its biological activities in diabetic rats.

PubMed

Reddy, Chagam Koteswara; Suriya, M; Vidya, P V; Haripriya, Sundaramoorthy

2017-01-01

This study describes a simple method of preparation and physico-chemical properties of modified starches (type-3 resistant starches) from banana (Musa AAB), and the modified starches investigated as functional food with a beneficial effect on type-2 diabetes. RS3 was prepared using a method combined with debranching modification and physical modification; native and modifies starches were characterized by scanning electron microscope (SEM), powder X-ray diffraction (XRD), differential scanning calorimetry (DSC) and rapid visco analyzer (RVA). Use of the enzymatic and physical modification methodology, improved the yield of RS (26.62%) from Musa AAB. A reduced viscosity and swelling power; increased transition temperatures, water absorption capacity and solubility index with B-type crystalline pattern and loss of granular appearance were observed during the debranching modification and physical modification. The modified starches exhibited beneficial health effects in diabetic and HFD rats who consumed it. These results recommend that dietary feeding of RS3 was effective in the regulation of glucose and lipid profile in serum and suppressing the oxidative stress in rats under diabetic and HFD condition. This current study provides new bioactive starches, with potential applications in the food and non-food industries. Copyright © 2016 Elsevier B.V. All rights reserved.

Cocaine cues retain silent traces of an excitatory history after conversion into conditioned inhibitors: 'the ghost in the addict'.

PubMed

Weiss, Stanley J; Kearns, David N

2016-04-01

The present experiment investigated the extent to which the A+/AB- conditioned inhibition procedure could counteract an excitatory drug-related conditioning history. In two groups of rats, a light stimulus was established as a signal for the absence of cocaine. For the History group, the light had previously been a discriminative stimulus (S) that occasioned cocaine self-administration and could thus be classified as a cocaine excitor. In comparison, the No-History group first encountered the light during conditioned inhibition training. During conditioned inhibition training, both groups self-administered cocaine during tone as well as during click Ss, whereas drug seeking was eliminated in click-plus-light, wherein cocaine was not available (A+/AB-). Drug seeking was essentially eliminated in both groups. Nevertheless, on a summation test the light reduced cocaine seeking occasioned by the tone S by 95% in the No-History group, but by less than 50% in the History group. This summation test result showed that the effects of a drug-related history persisted even after the light was converted into an effective conditioned inhibitor on the training baseline through the powerful A+/AB- procedure. Future research should seek procedures that produce even stronger conditioned inhibition that eliminates such residual 'silent' drug excitation, the 'ghost in the addict'.

The Epidemiology of Antisocial Behavioral Syndromes in Adulthood: Results From the National Epidemiologic Survey on Alcohol and Related Conditions-III.

PubMed

Goldstein, Risë B; Chou, S Patricia; Saha, Tulshi D; Smith, Sharon M; Jung, Jeesun; Zhang, Haitao; Pickering, Roger P; Ruan, W June; Huang, Boji; Grant, Bridget F

2017-01-01

To present current, nationally representative US findings on prevalence, correlates, psychiatric comorbidity, disability, and treatment of DSM-5 antisocial personality disorder (ASPD) and adulthood antisocial behavioral syndrome without conduct disorder before 15 years of age (AABS). Face-to-face interviews were conducted with respondents (N = 36,309) in the 2012-2013 National Epidemiologic Survey on Alcohol and Related Conditions-III. DSM-5 alcohol, nicotine, and specific drug use disorders and selected mood, anxiety, trauma-related, eating, and personality disorders were assessed using the Alcohol Use Disorder and Associated Disabilities Interview Schedule-5. Prevalences of ASPD and AABS were 4.3% and 20.3%, respectively, and were highest among male, white, Native American, younger, and unmarried respondents, those with high school or less education, lower incomes, and Western residence. Both antisocial syndromes were significantly associated with 12-month and lifetime substance use, dysthymia/persistent depressive, bipolar I, posttraumatic stress, and borderline and schizotypal personality disorders (odds ratios [ORs] = 1.2-7.0). ASPD was additionally associated with 12-month agoraphobia and lifetime generalized anxiety disorder (ORs = 1.3-1.6); AABS, with 12-month and lifetime major depressive and 12-month generalized anxiety disorders (ORs = 1.2-1.3). Both were associated with significant disability (P < .001 to .01). Most antisocial survey respondents were untreated. One in 4 US adults exhibits syndromal antisocial behavior, with similar sociodemographic and psychiatric correlates and disability regardless of whether onset occurred before 15 years of age, illustrating the clinical and public health significance of both ASPD and AABS. In addition to laying groundwork for estimates of social and economic costs, and further etiologic and nosologic research, these findings highlight the urgency of effectively preventing and treating antisocial syndromes, including investigation of whether treatment for comorbidity hastens symptomatic remission and improves quality-of-life outcomes. © Copyright 2017 Physicians Postgraduate Press, Inc.

Near-infrared Spectroscopy of 2M0441+2301 AabBab: A Quadruple System Spanning the Stellar to Planetary Mass Regimes

NASA Astrophysics Data System (ADS)

Bowler, Brendan P.; Hillenbrand, Lynne A.

2015-10-01

We present Keck/NIRC2 and OSIRIS near-infrared imaging and spectroscopy of 2M0441+2301 AabBab, a young (1-3 Myr) hierarchical quadruple system comprising a low-mass star, two brown dwarfs, and a planetary-mass companion in Taurus. All four components show spectroscopic signs of low surface gravity, and both 2M0441+2301 Aa and Ab possess Paβ emission indicating they each harbor accretion subdisks. Astrometry spanning 2008-2014 reveals orbital motion in both the Aab (0.″23 separation) and Bab (0.″095 separation) pairs, although the implied orbital periods of >300 years mean dynamical masses will not be possible in the near future. The faintest component (2M0441+2301 Bb) has an angular H-band shape, strong molecular absorption (VO, CO, H2O, and FeH), and shallow alkali lines, confirming its young age, late spectral type (L1 ± 1), and low temperature (≈1800 K). With individual masses of {200}-50+100 MJup, 35 ± 5 MJup, 19 ± 3 MJup, and 9.8 ± 1.8 MJup, 2M0441+2301 AabBab is the lowest-mass quadruple system known. Its hierarchical orbital architecture and mass ratios imply that it formed from the collapse and fragmentation of a molecular cloud core, demonstrating that planetary-mass companions can originate from a stellar-like pathway analogous to higher-mass quadruple star systems as first speculated by Todorov et al. More generally, cloud fragmentation may be an important formation pathway for the massive exoplanets that are now regularly being imaged on wide orbits. The data presented herein were obtained at the W. M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California and the National Aeronautics and Space Administration. The Observatory was made possible by the generous financial support of the W. M. Keck Foundation.

Effect of packing material on organic matter removal efficiency in an anaerobic-aerobic baffled bioreactor.

PubMed

Tabla-Hernandez, Jacobo; Lopez-Galvan, Edgar

2018-04-01

The aim of the present work was to study the effect of packing material on the organic matter removal efficiency (OMRE) in an anaerobic-aerobic baffled bioreactor (AAB). For this purpose, two different experiments were conducted with two types of packing material: activated carbon (AC) particles and polyurethane foam (PF). The system consisted of two treatments; the first one was anaerobic, where hydrolysis, acetogenesis and methanogenesis took place. In anaerobic chambers, there were no packing materials and the operating conditions were the same in both experiments. The second treatment was aerobic and both materials were placed at different times as a bedding. The parameters measured were chemical oxygen demand (COD), dissolved chemical oxygen demand (COD d ), total organic carbon (TOC), nitrate concentration (NO 3 - ), ammonium concentration (NH 4 + ), electric conductivity (σ), alkalinity (Alky) and hydrogen potential (pH). Paired t-Student test showed that there was no significant difference in the OMRE in anaerobic treatment, whereas there was in aerobic treatment, due to the effect of packing material. NH 4 + and NO 3 - showed a negative Pearson correlation in both experiments, indicating the presence of the nitrification process in the aerobic chamber. AAB packed with PF had better performance at obtaining an OMRE of around 63%, whereas AAB packed with AC presented an OMRE of around 51%.

Human milk is a source of lactic acid bacteria for the infant gut.

PubMed

Martín, Rocío; Langa, Susana; Reviriego, Carlota; Jimínez, Esther; Marín, María L; Xaus, Jordi; Fernández, Leonides; Rodríguez, Juan M

2003-12-01

To investigate whether human breast milk contains potentially probiotic lactic acid bacteria, and therefore, whether it can be considered a synbiotic food. Study design Lactic acid bacteria were isolated from milk, mammary areola, and breast skin of eight healthy mothers and oral swabs and feces of their respective breast-fed infants. Some isolates (178 from each mother and newborn pair) were randomly selected and submitted to randomly amplified polymorphic DNA (RAPD) polymerase chain reaction analysis, and those that displayed identical RAPD patterns were identified by 16S rDNA sequencing. Within each mother and newborn pair, some rod-shaped lactic acid bacteria isolated from mammary areola, breast milk, and infant oral swabs and feces displayed identical RAPD profiles. All of them, independently from the mother and child pair, were identified as Lactobacillus gasseri. Similarly, among coccoid lactic acid bacteria from these different sources, some shared an identical RAPD pattern and were identified as Enterococcus faecium. In contrast, none of the lactic acid bacteria isolated from breast skin shared RAPD profiles with lactic acid bacteria of the other sources. Breast-feeding can be a significant source of lactic acid bacteria to the infant gut. Lactic acid bacteria present in milk may have an endogenous origin and may not be the result of contamination from the surrounding breast skin.

Effect of deep-fat frying on ascorbic acid, carotenoids and potassium contents of plantain cylinders.

PubMed

Rojas-Gonzalez, Juan A; Avallone, Sylvie; Brat, Pierre; Trystram, Gilles; Bohuon, Philippe

2006-01-01

The influence of thermal treatment (frying of plantain) on the micronutrients ascorbic acid, potassium and carotenoids is evaluated. Cylinders (diameter 30 mm, thickness 10 mm) of plantain (Musa AAB 'barraganete') were fried at four thermal treatments (120-180 degrees C and from 24 to 4 min) to obtain products with approximately the same water content (approximately 0.8+/-0.02 kg/kg1) and fat content (approximately 0.15+/-0.06 kg/kg). The thermal study used the cook value and the mean cook value as indicators of the effect of several different treatment temperatures and times on quality. Deep-fat frying had no significant effect on carotenoid contents at any frying conditions, and on potassium content, except at 120 degrees C and 24 min (loss

The effect of montelukast and antiadhesion barrier solution on the capsule formation after insertion of silicone implants in a white rat model.

PubMed

Yang, J-D; Kwon, O-H; Lee, J-W; Chung, H-Y; Cho, B-C; Park, H-Y; Kim, T-G

2013-01-01

Capsular contracture is one of the most severe complications that can occur in breast surgery following silicone implant insertion. The purpose of this study was to investigate the effect of montelukast and antiadhesion barrier solution (AABS) on reducing capsular formation and their possible synergism. This study was approved by the Animal Ethics Committee (Reference No. KNU 2012-33) and was conducted in accordance with the Kyungpook National University - Institutional Animal Care and Use Committee, Animal Ethics Committee. The experiments in this study were conducted in vivo in 4 groups of 24 rats. Following silicone implant insertion, the pocket was injected with different agents. Group I (control group) was given normal saline injections into the pocket and fed with pure water. Group II was given injections of AABS and fed with pure water. Group III was given injections of normal saline and the medication montelukast during the experimental period. Group IV was given injections of AABS and montelukast as postoperative medication. Peri-implant capsules were excised after 8 weeks and were evaluated for transparency, inflammatory cell content, capsule thickness, collagen pattern and TGF-β expression. The capsules in the experimental groups (i.e., groups II-IV) were significantly more transparent than those in group I (controls; p < 0.05, Student's t test). The mean capsule thickness of the experimental groups II (296 ± 14.76 μm), III (280 ± 14.77 μm) and IV (276 ± 39.28 μm) was smaller than that of the control group I (361 ± 35.43 μm). Compared to the control group, the histologic findings in the experimental groups suggested a decreased inflammatory response occurring in the peri-implant capsules as they exhibited minor vascularization and a reduced number of mast cells and macrophages. The collagen patterns in the experimental groups were of a lower density than in the control group with the former showing a loose, tidy collagen pattern. The amounts of TGF-β and collagen I were higher in the control group than in the experimental groups. Group IV (the synergic effect group) had a more pronounced effect on all the parameters examined than that in groups II and III with separate drug administration. Montelukast and AABS reduced the thickness, the inflammatory cell infiltrate and the myofibroblast content of the peri-implant capsules around silicone implants in this white rat model. They lowered the expression of the fibrotic mediator, TGF-β, and inhibited the peri-implant capsular fibrosis. Therefore, montelukast and AABS are effective in the reduction of silicone-induced peri-implant capsular formation.

Linear α-(1 → 6)-d-glucan from Bifidobacterium bifidum BIM В-733D is low molecular mass biopolymer with unique immunochemical properties.

PubMed

Kiseleva, Elena P; Mikhailopulo, Konstantin I; Zdorovenko, Evelina L; Knirel, Yuriy A; Novik, Galina I

2017-12-20

Role of microorganisms in induction of/protection from autoimmune diseases is proven though molecular mechanisms and bacterial/viral/yeast biopolymers responsible for these effects are in the research stage. Autoantobodies (AAbs) to thyroid peroxidase (anti-TPO) and thyroglobulin (anti-Tg) as well as AAbs to transglutaminase 2 (anti-TG2) and antibodies to gliadins (anti-gliadins) are serological markers of autoimmune thyroid disease and celiac disease, respectively, and players in pathogenesis of these autoimmune diseases. In current study, biopolymer of Bifidobacterium bifidum BIM В-733D that interacts selectively with anti-gliadins (Bb-G anti-gliadins ) was isolated by affinity chromatography with anti-gliadins, purified by size exclusion chromatography on TSK 40 gel and identified by NMR as linear α-(1 → 6)-d-glucan with molecular mass about 5000 Da. It was proven that compounds Bb-G anti-gliadins and Bb-G anti-TPO /Bb-G anti-Tg isolated early from the same strain [Kiseleva, E. P. et al., Benef Microbes.2013, 4, 375 -391] are the same substance designated G Bb . Its unique immunochemical property is the ability to interact selectively with anti-TPO, anti-Tg, anti-TG2 and anti-gliadins in presence of no less than 10-fold excess of total immunoglobulins of class G (tIgG), as it was proven by ELISA. Synthesis of G Bb -bovine serum albumin (G Bb -BSA) conjugate is an example of increasing the reliability and reproducibility of ELISA results by mediated immobilization of a polysaccharide covalently attached to a well-adsorbed protein. Taking into account that there are population of bispecific anti-gliadins (anti-gliadins and anti-TG2 simultaneously) we regard our data as first argument in favor of hypothesis that G Bb differentiates between human AAbs per se and other human Ig (e.g. antibodies to antigens of infectious agents) due to its binding with a yet unidentified site which is present in the molecules of all AAbs (independently on their specificity) and absent in other human Igs. Copyright © 2018 Elsevier Ltd. All rights reserved.

Photoenhanced anaerobic digestion of organic acids

DOEpatents

Weaver, Paul F.

1990-01-01

A process is described for rapid conversion of organic acids and alcohols anaerobic digesters into hydrogen and carbon dioxide, the optimal precursor substrates for production of methane. The process includes addition of photosynthetic bacteria to the digester and exposure of the bacteria to radiant energy (e.g., solar energy). The process also increases the pH stability of the digester to prevent failure of the digester. Preferred substrates for photosynthetic bacteria are the organic acid and alcohol waste products of fermentative bacteria. In mixed culture with methanogenic bacteria or in defined co-culture with non-aceticlastic methanogenic bacteria, photosynthetic bacteria are capable of facilitating the conversion or organic acids and alcohols into methane with low levels of light energy input.

Preservation of acidified cucumbers with a natural preservative combination of fumaric acid and allyl isothiocyanate that target lactic acid bacteria and yeasts

USDA-ARS?s Scientific Manuscript database

Without the addition of preservative compounds cucumbers acidified with 150 mM acetic acid with pH adjusted to 3.5 typically undergo fermentation by lactic acid bacteria. Fumaric acid (20 mM) inhibited growth of Lactobacillus plantarum and the lactic acid bacteria present on fresh cucumbers, but sp...

Lactic acid bacteria of meat and meat products.

PubMed

Egan, A F

1983-09-01

When the growth of aerobic spoilage bacteria is inhibited, lactic acid bacteria may become the dominant component of the microbial flora of meats. This occurs with cured meats and with meats packaged in films of low gas permeability. The presence of a flora of psychrotrophic lactic acid bacteria on vacuum-packaged fresh chilled meats usually ensures that shelf-life is maximal. When these organisms spoil meats it is generally by causing souring, however other specific types of spoilage do occur. Some strains cause slime formation and greening of cured meats, and others may produce hydrogen sulphide during growth on vacuum-packaged beef. The safety and stability of fermented sausages depends upon fermentation caused by lactic acid bacteria. Overall the presence on meats of lactic acid bacteria is more desirable than that of the types of bacteria they have replaced.

Preliminary Analysis of Lipids and Fatty Acids of Green Bacteria and Chloroflexus aurantiacus

PubMed Central

Kenyon, Christine N.; Gray, Alane M.

1974-01-01

The complex lipids and fatty acids of the seven type species of green bacteria and three strains of Chloroflexus aurantiacus were analyzed. The green bacteria contained lipids that behaved as cardiolipin and phosphatidylglycerol on thin-layer chromatography. They did not contain phosphatidylethanolamine or phosphatidylserine. Similarly, Chloroflexus contained lipids that behaved as phosphatidylglycerol and phosphatidylinositol on thin-layer chromatography and did not contain phosphatidylethanolamine or phosphatidylserine. The green bacteria contained glycolipids I and II of Constantopoulos and Bloch (monogalactosyldiglyceride and a galactose- and rhamnose-containing diglyceride). Chloroflexus exhibited galactose-containing glycolipids that behaved identically with the mono- and digalactosyldiglycerides of spinach on thin-layer chromatography, and each contained galactose as well as at least one other sugar. The fatty acids of both groups of bacteria consisted entirely of saturated and monounsaturated fatty acids. In the green bacteria, myristic, palmitic, and hexadecenoic acids predominated. In Chloroflexus, palmitic, stearic, and oleic acids predominated. The positions of the double bonds in the monounsaturated fatty acids of Chloroflexus indicated synthesis by the anaerobic pathway. The lipid analyses suggest a close relationship between the green bacteria and Chloroflexus and further suggest that these groups of photosynthetic bacteria are more closely related to the blue-green algae than are the purple bacteria. Images PMID:4421249

High School Sports Involvement Diminishes the Association Between Childhood Conduct Disorder and Adult Antisocial Behavior

PubMed Central

Samek, Diana R.; Elkins, Irene J.; Keyes, Margaret A.; Iacono, William G.; McGue, Matt

2015-01-01

Purpose Life course–persistent antisocial behavior manifests as a display of aggressive and antisocial behavior beginning in childhood (conduct disorder [CD]) and lasting through adulthood (adult antisocial personality disorder). This study aimed to build on prior research by evaluating whether involvement in high school sports helped attenuate the association between CD and subsequent adult antisocial behavior (AAB). Methods A prospective sample of 967 male and female adolescents (56% adopted) was used. Structured interviews were used to assess CD (symptoms before the age of 15 years), involvement in sports during high school, and past-year adult antisocial personality disorder symptoms in young adulthood (M age = 22.4 years). Results As expected, the association between CD and AAB was significantly less for those involved in sports (β = .28; p < .001) compared with those not involved in sports (β = .49; p < .001), χ2(1) = 4.13; p = .04. This difference remained after including known covariates of antisocial behavior in the model (age, gender, adoption status), and results were consistent across males and females. Involvement in other extracurricular activities (e.g., student government, plays, clubs) did not significantly moderate the relationship between CD and AAB. Conclusions Although selection effects were evident (those with more CD symptoms were less likely to be involved in sports), findings nevertheless suggest high school sports involvement may be a notable factor related to disrupting persistent antisocial behavior beginning in childhood and adolescence and lasting through young adulthood. Implications are discussed. PMID:25937472

A working memory bias for alcohol-related stimuli depends on drinking score.

PubMed

Kessler, Klaus; Pajak, Katarzyna Malgorzata; Harkin, Ben; Jones, Barry

2013-03-01

We tested 44 participants with respect to their working memory (WM) performance on alcohol-related versus neutral visual stimuli. Previously an alcohol attentional bias (AAB) had been reported using these stimuli, where the attention of frequent drinkers was automatically drawn toward alcohol-related items (e.g., beer bottle). The present study set out to provide evidence for an alcohol memory bias (AMB) that would persist over longer time-scales than the AAB. The WM task we used required memorizing 4 stimuli in their correct locations and a visual interference task was administered during a 4-sec delay interval. A subsequent probe required participants to indicate whether a stimulus was shown in the correct or incorrect location. For each participant we calculated a drinking score based on 3 items derived from the Alcohol Use Questionnaire, and we observed that higher scorers better remembered alcohol-related images compared with lower scorers, particularly when these were presented in their correct locations upon recall. This provides first evidence for an AMB. It is important to highlight that this effect persisted over a 4-sec delay period including a visual interference task that erased iconic memories and diverted attention away from the encoded items, thus the AMB cannot be reduced to the previously reported AAB. Our finding calls for further investigation of alcohol-related cognitive biases in WM, and we propose a preliminary model that may guide future research. (PsycINFO Database Record (c) 2013 APA, all rights reserved).

Characterization of lactic acid bacteria from local cow´s milk kefir

NASA Astrophysics Data System (ADS)

Ismail, YS; Yulvizar, C.; Mazhitov, B.

2018-03-01

One of products from milk fermentation is kefir. It is made by adding kefir grains which are composed of lactic acid bacteria and yeast into milk. The lactic acid bacteria are a group of bacteria that produce antimicrobial substances and able to inhibit the growth of pathogenic bacteria. In this research, the lactic acid bacteria were isolated from Aceh local cow`s milk kefir to determine the genus of the isolates. The methods used in the characterization of lactic acid bacteria are colony morphology, cell morphology, and biochemical tests which includes a catalase test; 5%, 6.5%, and 10% salt endurance tests; 37°C and 14°C temperature endurance tests, SIM test, TSIA test, MR-VP test, and O/F test. Of the four isolates found from the cow’s milk kefir, two isolates were confirmed as lactic acid bacteria (isolates SK-1 and SK-4). Both isolates are Gram positive bacteria, and have negative catalase activity. From the observations of colony morphology, cell morphology, and biochemical tests, it was found that the genus of SK-1 is Lactobacillus and the genus of SK-4 is Enterococcus.

Filling gaps in bacterial amino acid biosynthesis pathways with high-throughput genetics.

PubMed

Price, Morgan N; Zane, Grant M; Kuehl, Jennifer V; Melnyk, Ryan A; Wall, Judy D; Deutschbauer, Adam M; Arkin, Adam P

2018-01-01

For many bacteria with sequenced genomes, we do not understand how they synthesize some amino acids. This makes it challenging to reconstruct their metabolism, and has led to speculation that bacteria might be cross-feeding amino acids. We studied heterotrophic bacteria from 10 different genera that grow without added amino acids even though an automated tool predicts that the bacteria have gaps in their amino acid synthesis pathways. Across these bacteria, there were 11 gaps in their amino acid biosynthesis pathways that we could not fill using current knowledge. Using genome-wide mutant fitness data, we identified novel enzymes that fill 9 of the 11 gaps and hence explain the biosynthesis of methionine, threonine, serine, or histidine by bacteria from six genera. We also found that the sulfate-reducing bacterium Desulfovibrio vulgaris synthesizes homocysteine (which is a precursor to methionine) by using DUF39, NIL/ferredoxin, and COG2122 proteins, and that homoserine is not an intermediate in this pathway. Our results suggest that most free-living bacteria can likely make all 20 amino acids and illustrate how high-throughput genetics can uncover previously-unknown amino acid biosynthesis genes.

Filling gaps in bacterial amino acid biosynthesis pathways with high-throughput genetics

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

Price, Morgan N.; Zane, Grant M.; Kuehl, Jennifer V.

For many bacteria with sequenced genomes, we do not understand how they synthesize some amino acids. This makes it challenging to reconstruct their metabolism, and has led to speculation that bacteria might be cross-feeding amino acids. Here, we studied heterotrophic bacteria from 10 different genera that grow without added amino acids even though an automated tool predicts that the bacteria have gaps in their amino acid synthesis pathways. Across these bacteria, there were 11 gaps in their amino acid biosynthesis pathways that we could not fill using current knowledge. Using genome-wide mutant fitness data, we identified novel enzymes that fillmore » 9 of the 11 gaps and hence explain the biosynthesis of methionine, threonine, serine, or histidine by bacteria from six genera. We also found that the sulfate-reducing bacterium Desulfovibrio vulgaris synthesizes homocysteine (which is a precursor to methionine) by using DUF39, NIL/ferredoxin, and COG2122 proteins, and that homoserine is not an intermediate in this pathway. Our results suggest that most free-living bacteria can likely make all 20 amino acids and illustrate how high-throughput genetics can uncover previously-unknown amino acid biosynthesis genes.« less

Filling gaps in bacterial amino acid biosynthesis pathways with high-throughput genetics

DOE PAGES

Price, Morgan N.; Zane, Grant M.; Kuehl, Jennifer V.; ...

2018-01-11

For many bacteria with sequenced genomes, we do not understand how they synthesize some amino acids. This makes it challenging to reconstruct their metabolism, and has led to speculation that bacteria might be cross-feeding amino acids. Here, we studied heterotrophic bacteria from 10 different genera that grow without added amino acids even though an automated tool predicts that the bacteria have gaps in their amino acid synthesis pathways. Across these bacteria, there were 11 gaps in their amino acid biosynthesis pathways that we could not fill using current knowledge. Using genome-wide mutant fitness data, we identified novel enzymes that fillmore » 9 of the 11 gaps and hence explain the biosynthesis of methionine, threonine, serine, or histidine by bacteria from six genera. We also found that the sulfate-reducing bacterium Desulfovibrio vulgaris synthesizes homocysteine (which is a precursor to methionine) by using DUF39, NIL/ferredoxin, and COG2122 proteins, and that homoserine is not an intermediate in this pathway. Our results suggest that most free-living bacteria can likely make all 20 amino acids and illustrate how high-throughput genetics can uncover previously-unknown amino acid biosynthesis genes.« less

Filling gaps in bacterial amino acid biosynthesis pathways with high-throughput genetics

PubMed Central

Kuehl, Jennifer V.; Melnyk, Ryan A.; Deutschbauer, Adam M.; Arkin, Adam P.

2018-01-01

For many bacteria with sequenced genomes, we do not understand how they synthesize some amino acids. This makes it challenging to reconstruct their metabolism, and has led to speculation that bacteria might be cross-feeding amino acids. We studied heterotrophic bacteria from 10 different genera that grow without added amino acids even though an automated tool predicts that the bacteria have gaps in their amino acid synthesis pathways. Across these bacteria, there were 11 gaps in their amino acid biosynthesis pathways that we could not fill using current knowledge. Using genome-wide mutant fitness data, we identified novel enzymes that fill 9 of the 11 gaps and hence explain the biosynthesis of methionine, threonine, serine, or histidine by bacteria from six genera. We also found that the sulfate-reducing bacterium Desulfovibrio vulgaris synthesizes homocysteine (which is a precursor to methionine) by using DUF39, NIL/ferredoxin, and COG2122 proteins, and that homoserine is not an intermediate in this pathway. Our results suggest that most free-living bacteria can likely make all 20 amino acids and illustrate how high-throughput genetics can uncover previously-unknown amino acid biosynthesis genes. PMID:29324779

Stimulation of Lactic Acid Bacteria by a Micrococcus Isolate: Evidence for Multiple Effects

PubMed Central

Nath, K. R.; Wagner, B. J.

1973-01-01

Growth of, and rate of acid production by, six cultures of lactic acid bacteria were increased in the presence of Micrococcus isolate F4 or a preparation of its capsular material. Concentrations of hydrogen peroxide found in pure cultures of the lactic acid bacteria were not detectable, or were greatly reduced, in mixed culture with Micrococcus isolate F4. The capsular material was not as effective as whole cells in preventing accumulation of H2O2. Catalase stimulated growth of, and the rate of acid production by, the lactic acid bacteria, but not to the same extent as Micrococcus isolate F4 in some cultures. The existence of two mechanisms for micrococcal stimulation of the lactic acid bacteria is postulated. One mechanism involves removal of H2O2; the other has not been characterized. PMID:4199337

Lactic acid bacteria: promising supplements for enhancing the biological activities of kombucha.

PubMed

Nguyen, Nguyen Khoi; Dong, Ngan Thi Ngoc; Nguyen, Huong Thuy; Le, Phu Hong

2015-01-01

Kombucha is sweetened black tea that is fermented by a symbiosis of bacteria and yeast embedded within a cellulose membrane. It is considered a health drink in many countries because it is a rich source of vitamins and may have other health benefits. It has previously been reported that adding lactic acid bacteria (Lactobacillus) strains to kombucha can enhance its biological functions, but in that study only lactic acid bacteria isolated from kefir grains were tested. There are many other natural sources of lactic acid bacteria. In this study, we examined the effects of lactic acid bacteria from various fermented Vietnamese food sources (pickled cabbage, kefir and kombucha) on kombucha's three main biological functions: glucuronic acid production, antibacterial activity and antioxidant ability. Glucuronic acid production was determined by high-performance liquid chromatography-mass spectrometry, antibacterial activity was assessed by the agar-well diffusion method and antioxidant ability was evaluated by determining the 2,2-diphenyl-1-picrylhydrazyl radical scavenging capacity. Four strains of food-borne pathogenic bacteria were used in our antibacterial experiments: Listeria monocytogenes ATCC 19111, Escherichia coli ATCC 8739, Salmonella typhimurium ATCC 14028 and Bacillus cereus ATCC 11778. Our findings showed that lactic acid bacteria strains isolated from kefir are superior to those from other sources for improving glucuronic acid production and enhancing the antibacterial and antioxidant activities of kombucha. This study illustrates the potential of Lactobacillus casei and Lactobacillus plantarum isolated from kefir as biosupplements for enhancing the bioactivities of kombucha.

Lactic acid bacteria in the quality improvement and depreciation of wine.

PubMed

Lonvaud-Funel, A

1999-01-01

The winemaking process includes two main steps: lactic acid bacteria are responsible for the malolactic fermentation which follows the alcoholic fermentation by yeasts. Both types of microorganisms are present on grapes and on cellar equipment. Yeasts are better adapted to growth in grape must than lactic acid bacteria, so the alcoholic fermentation starts quickly. In must, up to ten lactic acid bacteria species can be identified. They belong to the Lactobacillus, Pediococcus, Leuconostoc and Oenococcus genera. Throughout alcoholic fermentation, a natural selection occurs and finally the dominant species is O. oeni, due to interactions between yeasts and bacteria and between bacteria themselves. After bacterial growth, when the population is over 10(6) CFU/ml, malolactic transformation is the obvious change in wine composition. However, many other substrates can be metabolized. Some like remaining sugars and citric acid are always assimilated by lactic acid bacteria, thus providing them with energy and carbon. Other substrates such as some amino acids may be used following pathways restricted to strains carrying the adequate enzymes. Some strains can also produce exopolysaccharides. All these transformations greatly influence the sensory and hygienic quality of wine. Malic acid transformation is encouraged because it induces deacidification. Diacetyl produced from citric acid is also helpful to some extent. Sensory analyses show that many other reactions change the aromas and make malolactic fermentation beneficial, but they are as yet unknown. On the contrary, an excess of acetic acid, the synthesis of glucane, biogenic amines and precursors of ethylcarbamate are undesirable. Fortunately, lactic acid bacteria normally multiply in dry wines; moreover some of these activities are not widespread. Moreover, the most striking trait of wine lactic acid bacteria is their capacity to adapt to a hostile environment. The mechanisms for this are not yet completely elucidated. Molecular biology has provided some explanations for the behaviour and the metabolism of bacteria in wine. New tools are now available to detect the presence of desirable and undesirable strains. Even if much remains unknown, winemakers and oenologists can nowadays better control the process. By acting upon the diverse microflora and grape musts, they are more able to produce healthy and pleasant wines.

AmberAlert / DPS / DHSEM / AAB

Science.gov Websites

cooperative public service alert to aid in the safe recovery of abducted children. The Alaska AMBER Alert children to aid in their safe return. AMBER Alert Hotline: 866-AKAMBER - (866-252-6237) State of Alaska

Chemical compositions and glycemic responses to banana varieties.

PubMed

Hettiaratchi, U P K; Ekanayake, S; Welihinda, J

2011-06-01

Chemical compositions and glycemic indices of four varieties of banana (Musa spp.) (kolikuttu-Silk AAB, embul-Mysore AAB, anamalu-Gros Michel AAA, seeni kesel-Pisang Awak ABB) were determined. Silk, Gros Michel, Pisang Awak and Mysore contained the highest percentages of starch (14%), sucrose (38%), free glucose (29%) and fructose (58%) as a percentage of the total available carbohydrate content respectively. Total dietary fiber contents of four varieties ranged from 2.7 to 5.3%. Glycemic indices of Silk, Mysore, Gros Michel and Pisang Awak were 61 ± 5, 61 ± 6, 67 ± 7, 69 ± 9 and can be categorized as low against white bread as the standard. A single banana of the four varieties elicited a low glycemic load. Thus, consumption of a banana from any of these varieties can be recommended as a snack for healthy or diabetic patients who are under dietary management or pharmacological drugs to regulate blood glucose responses in between meals.

A first-principles study of the electrically tunable band gap in few-layer penta-graphene.

PubMed

Wang, Jinjin; Wang, Zhanyu; Zhang, R J; Zheng, Y X; Chen, L Y; Wang, S Y; Tsoo, Chia-Chin; Huang, Hung-Ji; Su, Wan-Sheng

2018-06-25

The structural and electronic properties of bilayer (AA- and AB-stacked) and tri-layer (AAA-, ABA- and AAB-stacked) penta-graphene (PG) have been investigated in the framework of density functional theory. The present results demonstrate that the ground state energy in AB stacking is lower than that in AA stacking, whereas ABA stacking is found to be the most energetically favorable, followed by AAB and AAA stackings. All considered model configurations are found to be semiconducting, independent of the stacking sequence. In the presence of a perpendicular electric field, their band gaps can be significantly reduced and completely closed at a specific critical electric field strength, demonstrating a Stark effect. These findings show that few-layer PG will have tremendous opportunities to be applied in nanoscale electronic and optoelectronic devices owing to its tunable band gap.

Differential staining of bacteria: acid fast stain.

PubMed

Reynolds, Jackie; Moyes, Rita B; Breakwell, Donald P

2009-11-01

Acid-fastness is an uncommon characteristic shared by the genera Mycobacterium (Section 10A) and Nocardia. Because of this feature, this stain is extremely helpful in identification of these bacteria. Although Gram positive, acid-fast bacteria do not take the crystal violet into the wall well, appearing very light purple rather than the deep purple of normal Gram-positive bacteria. (c) 2009 by John Wiley & Sons, Inc.

Thermal sensitivity of some plantain micronutrients during deep-fat frying.

PubMed

Avallone, Sylvie; Rojas-Gonzalez, Juan A; Trystram, Gilles; Bohuon, Philippe

2009-06-01

The impact of deep-fat frying on the micronutrient content of plantain (Musa AAB"barraganete") was evaluated during processing of plantain chips called "tostones." Water content, micronutrients (potassium, L-ascorbic acid, alpha-carotene, beta-carotene) content, and the temperature within the food were quantified during the course of frying. A nonisothermal kinetics analysis of the 1st-order reaction (micronutrient degradation) induced by deep-fat frying, particularly in terms of the spatial distribution of temperature, was proposed. The kinetic parameters (pre-exponential factor k(0,) activation energy E(a)) were identified by nonlinear optimization, minimizing the residual variance between the experimental and theoretical micronutrient content. Agreement between model and experimental values was checked. During 1st and 2nd frying, potassium was well retained while carotenoid contents decreased significantly. Moreover, L-ascorbic acid contents decreased significantly, just during 2nd frying. k(0) was identified as well as E(a) observed for L-ascorbic acid, alpha-carotene, and beta-carotene as 68.4 to 71.5, 79.6 to 84.9, and 85.9 to 88.6 kJ/mol, respectively. beta-carotene appeared to be more heat-resistant than alpha-carotene and L-ascorbic acid. The behavior of the nutritional markers appears to be the consequence of the thermal and hydric histories of the crust and of the heart of the plantain disk related to heat transfer during preparation of the "tostones."

Exogenous fatty acid metabolism in bacteria.

PubMed

Yao, Jiangwei; Rock, Charles O

2017-10-01

Bacterial type II fatty acid synthesis (FASII) is a target for novel antibiotic development. All bacteria encode for mechanisms to incorporate exogenous fatty acids, and some bacteria can use exogenous fatty acids to bypass FASII inhibition. Bacteria encode three different mechanisms for activating exogenous fatty acids for incorporation into phospholipid synthesis. Exogenous fatty acids are converted into acyl-CoA in Gammaproteobacteria such as E. coli. Acyl-CoA molecules constitute a separate pool from endogenously synthesized acyl-ACP. Acyl-CoA can be used for phospholipid synthesis or broken down by β-oxidation, but cannot be used for lipopolysaccharide synthesis. Exogenous fatty acids are converted into acyl-ACP in some Gram-negative bacteria. The resulting acyl-ACP undergoes the same fates as endogenously synthesized acyl-ACP. Exogenous fatty acids are converted into acyl-phosphates in Gram-positive bacteria, and can be used for phospholipid synthesis or become acyl-ACP. Only the order Lactobacillales can use exogenous fatty acids to bypass FASII inhibition. FASII shuts down completely in presence of exogenous fatty acids in Lactobacillales, allowing Lactobacillales to synthesize phospholipids entirely from exogenous fatty acids. Inhibition of FASII cannot be bypassed in other bacteria because FASII is only partially down-regulated in presence of exogenous fatty acid or FASII is required to synthesize essential metabolites such as β-hydroxyacyl-ACP. Certain selective pressures such as FASII inhibition or growth in biofilms can select for naturally occurring one step mutations that attenuate endogenous fatty acid synthesis. Although attempts have been made to estimate the natural prevalence of these mutants, culture-independent metagenomic methods would provide a better estimate. Copyright © 2017 Elsevier B.V. and Société Française de Biochimie et Biologie Moléculaire (SFBBM). All rights reserved.

Racemization in Reverse: Evidence that D-Amino Acid Toxicity on Earth Is Controlled by Bacteria with Racemases

PubMed Central

Zhang, Gaosen; Sun, Henry J.

2014-01-01

D-amino acids are toxic for life on Earth. Yet, they form constantly due to geochemical racemization and bacterial growth (the cell walls of which contain D-amino acids), raising the fundamental question of how they ultimately are recycled. This study provides evidence that bacteria use D-amino acids as a source of nitrogen by running enzymatic racemization in reverse. Consequently, when soils are inundated with racemic amino acids, resident bacteria consume D- as well as L-enantiomers, either simultaneously or sequentially depending on the level of their racemase activity. Bacteria thus protect life on Earth by keeping environments D-amino acid free. PMID:24647559

Racemization in reverse: evidence that D-amino acid toxicity on Earth is controlled by bacteria with racemases.

PubMed

Zhang, Gaosen; Sun, Henry J

2014-01-01

D-amino acids are toxic for life on Earth. Yet, they form constantly due to geochemical racemization and bacterial growth (the cell walls of which contain D-amino acids), raising the fundamental question of how they ultimately are recycled. This study provides evidence that bacteria use D-amino acids as a source of nitrogen by running enzymatic racemization in reverse. Consequently, when soils are inundated with racemic amino acids, resident bacteria consume D- as well as L-enantiomers, either simultaneously or sequentially depending on the level of their racemase activity. Bacteria thus protect life on Earth by keeping environments D-amino acid free.

High School Sports Involvement Diminishes the Association Between Childhood Conduct Disorder and Adult Antisocial Behavior.

PubMed

Samek, Diana R; Elkins, Irene J; Keyes, Margaret A; Iacono, William G; McGue, Matt

2015-07-01

Life course-persistent antisocial behavior manifests as a display of aggressive and antisocial behavior beginning in childhood (conduct disorder [CD]) and lasting through adulthood (adult antisocial personality disorder). This study aimed to build on prior research by evaluating whether involvement in high school sports helped attenuate the association between CD and subsequent adult antisocial behavior (AAB). A prospective sample of 967 male and female adolescents (56% adopted) was used. Structured interviews were used to assess CD (symptoms before the age of 15 years), involvement in sports during high school, and past-year adult antisocial personality disorder symptoms in young adulthood (M age = 22.4 years). As expected, the association between CD and AAB was significantly less for those involved in sports (β = .28; p < .001) compared with those not involved in sports (β = .49; p < .001), χ(2)(1) = 4.13; p = .04. This difference remained after including known covariates of antisocial behavior in the model (age, gender, adoption status), and results were consistent across males and females. Involvement in other extracurricular activities (e.g., student government, plays, clubs) did not significantly moderate the relationship between CD and AAB. Although selection effects were evident (those with more CD symptoms were less likely to be involved in sports), findings nevertheless suggest high school sports involvement may be a notable factor related to disrupting persistent antisocial behavior beginning in childhood and adolescence and lasting through young adulthood. Implications are discussed. Copyright © 2015 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.

Lactic Acid Bacteria from Kefir Increase Cytotoxicity of Natural Killer Cells to Tumor Cells.

PubMed

Yamane, Takuya; Sakamoto, Tatsuji; Nakagaki, Takenori; Nakano, Yoshihisa

2018-03-27

The Japanese fermented beverage, homemade kefir, contains six lactic acid bacteria: Lactococcus. lactis subsp. Lactis , Lactococcus . lactis subsp. Cremoris , Lactococcus. Lactis subsp. Lactis biovar diacetylactis , Lactobacillus plantarum , Leuconostoc meseuteroides subsp. Cremoris and Lactobacillus casei . In this study, we found that a mixture of the six lactic acid bacteria from kefir increased the cytotoxicity of human natural killer KHYG-1 cells to human chronic myelogenous leukemia K562 cells and colorectal tumor HCT116 cells. Furthermore, levels of mRNA expression and secretion of IFN-γ (interferon gamma) increased in KHYG-1 cells that had been treated with the six lactic acid bacteria mixture from kefir. The results suggest that the six lactic acid bacteria mixture from kefir has strong effects on natural immunity and tumor cell cytotoxicity.

Lactic Acid Bacteria from Kefir Increase Cytotoxicity of Natural Killer Cells to Tumor Cells

PubMed Central

Yamane, Takuya; Sakamoto, Tatsuji; Nakagaki, Takenori; Nakano, Yoshihisa

2018-01-01

The Japanese fermented beverage, homemade kefir, contains six lactic acid bacteria: Lactococcus. lactis subsp. Lactis, Lactococcus. lactis subsp. Cremoris, Lactococcus. Lactis subsp. Lactis biovar diacetylactis, Lactobacillus plantarum, Leuconostoc meseuteroides subsp. Cremoris and Lactobacillus casei. In this study, we found that a mixture of the six lactic acid bacteria from kefir increased the cytotoxicity of human natural killer KHYG-1 cells to human chronic myelogenous leukemia K562 cells and colorectal tumor HCT116 cells. Furthermore, levels of mRNA expression and secretion of IFN-γ (interferon gamma) increased in KHYG-1 cells that had been treated with the six lactic acid bacteria mixture from kefir. The results suggest that the six lactic acid bacteria mixture from kefir has strong effects on natural immunity and tumor cell cytotoxicity. PMID:29584690

Functional genomics of lactic acid bacteria: from food to health

PubMed Central

2014-01-01

Genome analysis using next generation sequencing technologies has revolutionized the characterization of lactic acid bacteria and complete genomes of all major groups are now available. Comparative genomics has provided new insights into the natural and laboratory evolution of lactic acid bacteria and their environmental interactions. Moreover, functional genomics approaches have been used to understand the response of lactic acid bacteria to their environment. The results have been instrumental in understanding the adaptation of lactic acid bacteria in artisanal and industrial food fermentations as well as their interactions with the human host. Collectively, this has led to a detailed analysis of genes involved in colonization, persistence, interaction and signaling towards to the human host and its health. Finally, massive parallel genome re-sequencing has provided new opportunities in applied genomics, specifically in the characterization of novel non-GMO strains that have potential to be used in the food industry. Here, we provide an overview of the state of the art of these functional genomics approaches and their impact in understanding, applying and designing lactic acid bacteria for food and health. PMID:25186768

Functional genomics of lactic acid bacteria: from food to health.

PubMed

Douillard, François P; de Vos, Willem M

2014-08-29

Genome analysis using next generation sequencing technologies has revolutionized the characterization of lactic acid bacteria and complete genomes of all major groups are now available. Comparative genomics has provided new insights into the natural and laboratory evolution of lactic acid bacteria and their environmental interactions. Moreover, functional genomics approaches have been used to understand the response of lactic acid bacteria to their environment. The results have been instrumental in understanding the adaptation of lactic acid bacteria in artisanal and industrial food fermentations as well as their interactions with the human host. Collectively, this has led to a detailed analysis of genes involved in colonization, persistence, interaction and signaling towards to the human host and its health. Finally, massive parallel genome re-sequencing has provided new opportunities in applied genomics, specifically in the characterization of novel non-GMO strains that have potential to be used in the food industry. Here, we provide an overview of the state of the art of these functional genomics approaches and their impact in understanding, applying and designing lactic acid bacteria for food and health.

Cd(II) Sorption on Montmorillonite-Humic acid-Bacteria Composites

PubMed Central

Du, Huihui; Chen, Wenli; Cai, Peng; Rong, Xingmin; Dai, Ke; Peacock, Caroline L.; Huang, Qiaoyun

2016-01-01

Soil components (e.g., clays, bacteria and humic substances) are known to produce mineral-organic composites in natural systems. Herein, batch sorption isotherms, isothermal titration calorimetry (ITC), and Cd K-edge EXAFS spectroscopy were applied to investigate the binding characteristics of Cd on montmorillonite(Mont)-humic acid(HA)-bacteria composites. Additive sorption and non-additive Cd(II) sorption behaviour is observed for the binary Mont-bacteria and ternary Mont-HA-bacteria composite, respectively. Specifically, in the ternary composite, the coexistence of HA and bacteria inhibits Cd adsorption, suggesting a “blocking effect” between humic acid and bacterial cells. Large positive entropies (68.1 ~ 114.4 J/mol/K), and linear combination fitting of the EXAFS spectra for Cd adsorbed onto Mont-bacteria and Mont-HA-bacteria composites, demonstrate that Cd is mostly bound to bacterial surface functional groups by forming inner-sphere complexes. All our results together support the assertion that there is a degree of site masking in the ternary clay mineral-humic acid-bacteria composite. Because of this, in the ternary composite, Cd preferentially binds to the higher affinity components-i.e., the bacteria. PMID:26792640

Acetic acid bacteria in traditional balsamic vinegar: phenotypic traits relevant for starter cultures selection.

PubMed

Gullo, Maria; Giudici, Paolo

2008-06-30

This review focuses on acetic acid bacteria in traditional balsamic vinegar process. Although several studies are available on acetic acid bacteria ecology, metabolism and nutritional requirements, their activity as well as their technological traits in homemade vinegars as traditional balsamic vinegar is not well known. The basic technology to oxidise cooked grape must to produce traditional balsamic vinegar is performed by the so called "seed-vinegar" that is a microbiologically undefined starter culture obtained from spontaneous acetification of previous raw material. Selected starter cultures are the main technological improvement in order to innovate traditional balsamic vinegar production but until now they are rarely applied. To develop acetic acid bacteria starter cultures, selection criteria have to take in account composition of raw material, acetic acid bacteria metabolic activities, applied technology and desired characteristics of the final product. For traditional balsamic vinegar, significative phenotypical traits of acetic acid bacteria have been highlighted. Basic traits are: ethanol preferred and efficient oxidation, fast rate of acetic acid production, tolerance to high concentration of acetic acid, no overoxidation and low pH resistance. Specific traits are tolerance to high sugar concentration and to a wide temperature range. Gluconacetobacter europaeus and Acetobacter malorum strains can be evaluated to develop selected starter cultures since they show one or more suitable characters.

In vitro growth inhibition of mastitis causing bacteria by phenolics and metal chelators

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

Chew, B.P.; Tjoelker, L.W.; Tanaka, T.S.

1985-11-01

Antimicrobial activities of three phenolic compounds and four metal chelators were tested at 0, 250, 500, and 1000 ppm in vitro against four major mastitis-causing bacteria, Streptococcus agalactiae, Staphylococcus aureus, Klebsiella pnuemoniae, and Escherichia coli. Overall, butylated hydroxyanisole and tert-butylhydroquinone showed the greatest antimicrobial activity. These phenolics were bactericidal at 250 to 500 ppm against all four bacteria tested. The butylated hydroxytoluene was bactericidal against the gram-positive bacteria but was ineffective against the coliforms. At 250 ppm, disodium ethylenediaminetetraacetic acid was bactericidal against the gram-positive bacteria but much less effective against the gram-negatives. However, diethylene-triaminepentaacetic acid was more growth inhibitorymore » than ethylenediaminetetraacetic acid against the gram-negative bacteria and especially against Escherichia coli. All other compounds were generally much less effective or ineffective against all four microorganisms. Therefore, butylated hydroxyanisole, butylated hydroxytoluene, tert-butylhydroquinone, ethylenediaminetetraacetic acid, and diethylenetriaminepentaacetic acid may have practical implications in the prevention or treatment of bovine mastitis.« less

Comparative genomics of the lactic acid bacteria

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

Makarova, K.; Slesarev, A.; Wolf, Y.

Lactic acid-producing bacteria are associated with various plant and animal niches and play a key role in the production of fermented foods and beverages. We report nine genome sequences representing the phylogenetic and functional diversity of these bacteria. The small genomes of lactic acid bacteria encode a broad repertoire of transporters for efficient carbon and nitrogen acquisition from the nutritionally rich environments they inhabit and reflect a limited range of biosynthetic capabilities that indicate both prototrophic and auxotrophic strains. Phylogenetic analyses, comparison of gene content across the group, and reconstruction of ancestral gene sets indicate a combination of extensive genemore » loss and key gene acquisitions via horizontal gene transfer during the coevolution of lactic acid bacteria with their habitats.« less

Combined effects of organic acids and salt depending on type of acids and pathogens in laboratory media and acidified pickle.

PubMed

Bae, Y-M; Lee, S-Y

2015-08-01

In this study, the effectiveness of combining each of seven types of acids with 3% salt as a treatment against pathogens was investigated in laboratory media and acidified food. When 0.5% malic, 0.5% tartaric, 0.5% citric or 0.25% phosphoric acid was combined with 3% salt, there was a higher reduction in Gram-negative bacteria (Escherichia coli O157:H7 and Salmonella Typhimurium) compared to when using acid alone. However, when 0.5% acetic, 0.5% propionic or 0.25% lactic acid was combined with 3% salt, the salt provided protection against the acid treatment. However, the antagonistic effects of acetic, propionic and lactic acid seen with Gram-negative bacteria were not observed in Listeria monocytogenes. Antagonistic effects were similarly observed when E. coli O157:H7 was treated with acetic acid and salt in food. These results show that the addition of salt increases the resistance of Gram-negative bacteria to acid treatments when using acetic, propionic and lactic acid. This study shows that antagonistic effects were observed when Gram-negative bacteria were treated with organic acids of simple structure. It may provide useful information for understanding the acid resistance mechanism of Gram-negative bacteria and developing methods for preserving acidified food. © 2015 The Society for Applied Microbiology.

Lactic Acid Bacteria – Friend or Foe? Lactic Acid Bacteria in the Production of Polysaccharides and Fuel Ethanol

USDA-ARS?s Scientific Manuscript database

Lactic acid bacteria (LAB) have been widely used in the production of fermented foods and as probiotics. Alternan is a glucan with a distinctive backbone structure of alternating a-(1,6) and a-(1,3) linkages produced by the LAB Leuconostoc mesenteroides. In recent years, we have developed improved...

Metabolism of Oxo-Bile Acids and Characterization of Recombinant 12α-Hydroxysteroid Dehydrogenases from Bile Acid 7α-Dehydroxylating Human Gut Bacteria.

PubMed

Doden, Heidi; Sallam, Lina A; Devendran, Saravanan; Ly, Lindsey; Doden, Greta; Daniel, Steven L; Alves, João M P; Ridlon, Jason M

2018-05-15

Bile acids are important cholesterol-derived nutrient signaling hormones, synthesized in the liver, that act as detergents to solubilize dietary lipids. Bile acid 7α-dehydroxylating gut bacteria generate the toxic bile acids deoxycholic acid and lithocholic acid from host bile acids. The ability of these bacteria to remove the 7-hydroxyl group is partially dependent on 7α-hydroxysteroid dehydrogenase (HSDH) activity, which reduces 7-oxo-bile acids generated by other gut bacteria. 3α-HSDH has an important enzymatic activity in the bile acid 7α-dehydroxylation pathway. 12α-HSDH activity has been reported for the low-activity bile acid 7α-dehydroxylating bacterium Clostridium leptum ; however, this activity has not been reported for high-activity bile acid 7α-dehydroxylating bacteria, such as Clostridium scindens , Clostridium hylemonae , and Clostridium hiranonis Here, we demonstrate that these strains express bile acid 12α-HSDH. The recombinant enzymes were characterized from each species and shown to preferentially reduce 12-oxolithocholic acid to deoxycholic acid, with low activity against 12-oxochenodeoxycholic acid and reduced activity when bile acids were conjugated to taurine or glycine. Phylogenetic analysis suggests that 12α-HSDH is widespread among Firmicutes , Actinobacteria in the Coriobacteriaceae family, and human gut Archaea IMPORTANCE 12α-HSDH activity has been established in the medically important bile acid 7α-dehydroxylating bacteria C. scindens , C. hiranonis , and C. hylemonae Experiments with recombinant 12α-HSDHs from these strains are consistent with culture-based experiments that show a robust preference for 12-oxolithocholic acid over 12-oxochenodeoxycholic acid. Phylogenetic analysis identified novel members of the gut microbiome encoding 12α-HSDH. Future reengineering of 12α-HSDH enzymes to preferentially oxidize cholic acid may provide a means to industrially produce the therapeutic bile acid ursodeoxycholic acid. In addition, a cholic acid-specific 12α-HSDH expressed in the gut may be useful for the reduction in deoxycholic acid concentration, a bile acid implicated in cancers of the gastrointestinal (GI) tract. Copyright © 2018 American Society for Microbiology.

Acetic acid bacteria: A group of bacteria with versatile biotechnological applications.

PubMed

Saichana, Natsaran; Matsushita, Kazunobu; Adachi, Osao; Frébort, Ivo; Frebortova, Jitka

2015-11-01

Acetic acid bacteria are gram-negative obligate aerobic bacteria assigned to the family Acetobacteraceae of Alphaproteobacteria. They are members of the genera Acetobacter, Gluconobacter, Gluconacetobacter, Acidomonas, Asaia, Kozakia, Swaminathania, Saccharibacter, Neoasaia, Granulibacter, Tanticharoenia, Ameyamaea, Neokomagataea, and Komagataeibacter. Many strains of Acetobacter and Komagataeibacter have been known to possess high acetic acid fermentation ability as well as the acetic acid and ethanol resistance, which are considered to be useful features for industrial production of acetic acid and vinegar, the commercial product. On the other hand, Gluconobacter strains have the ability to perform oxidative fermentation of various sugars, sugar alcohols, and sugar acids leading to the formation of several valuable products. Thermotolerant strains of acetic acid bacteria were isolated in order to serve as the new strains of choice for industrial fermentations, in which the cooling costs for maintaining optimum growth and production temperature in the fermentation vessels could be significantly reduced. Genetic modifications by adaptation and genetic engineering were also applied to improve their properties, such as productivity and heat resistance. Copyright © 2014 Elsevier Inc. All rights reserved.

Citizen science datasets reveal drivers of spatial and temporal variation for anthropogenic litter on Great Lakes beaches.

PubMed

Vincent, Anna; Drag, Nate; Lyandres, Olga; Neville, Sarah; Hoellein, Timothy

2017-01-15

Accumulation of anthropogenic litter (AL) on marine beaches and its ecological effects have been a major focus of research. Recent studies suggest AL is also abundant in freshwater environments, but much less research has been conducted in freshwaters relative to oceans. The Adopt-a-BeachTM (AAB) program, administered by the Alliance for the Great Lakes, organizes volunteers to act as citizen scientists by collecting and maintaining data on AL abundance on Great Lakes beaches. Initial assessments of the AAB records quantified sources and abundance of AL on Lake Michigan beaches, and showed that plastic AL was >75% of AL on beaches across all five Great Lakes. However, AAB records have not yet been used to examine patterns of AL density and composition among beaches of all different substrate types (e.g., parks, rocky, sandy), across land-use categories (e.g., rural, suburban, urban), or among seasons (i.e., spring, summer, and fall). We found that most AL on beaches are consumer goods that most likely originate from beach visitors and nearby urban environments, rather than activities such as shipping, fishing, or illegal dumping. We also demonstrated that urban beaches and those with sand rather than rocks had higher AL density relative to other sites. Finally, we found that AL abundance is lowest during the summer, between the US holidays of Memorial Day (last Monday in May) and Labor Day (first Monday in September) at the urban beaches, while other beaches showed no seasonality. This research is a model for utilizing datasets collected by volunteers involved in citizen science programs, and will contribute to AL management by offering priorities for AL types and locations to maximize AL reduction. Copyright © 2016 Elsevier B.V. All rights reserved.

Metal/ceramic interface structures and segregation behavior in aluminum-based composites

DOE PAGES

Zhang, Xinming; Hu, Tao; Rufner, Jorgen F.; ...

2015-06-14

Trimodal Al alloy (AA) matrix composites consisting of ultrafine-­grained (UFG) and coarse-­ grained (CG) Al phases and micron-­sized B 4C ceramic reinforcement particles exhibit combinations of strength and ductility that render them useful for potential applications in the aerospace, defense and automotive industries. Tailoring of microstructures with specific mechanical properties requires a detailed understanding of interfacial structures to enable strong interface bonding between ceramic reinforcement and metal matrix, and thereby allow for effective load transfer. Trimodal AA metal matrix composites typically show three characteristics that are noteworthy: nanocrystalline grains in the vicinity of the B4C reinforcement particles; Mg segregation atmore » AA/B 4C interfaces; and the presence of amorphous interfacial layers separating nanocrystalline grains from B 4C particles. Interestingly, however, fundamental information related to the mechanisms responsible for these characteristics as well as information on local compositions and phases are absent in the current literature. Here in this study, we use high-­resolution transmission electron microscopy, energy-­dispersive X-­ray spectroscopy, electron energy-­loss spectroscopy, and precession assisted electron diffraction to gain fundamental insight into the mechanisms that affect the characteristics of AA/B 4C interfaces. Specifically, we determined interfacial structures, local composition and spatial distribution of the interfacial constituents. Near atomic resolution characterization revealed amorphous multilayers and a nanocrystalline region between Al phase and B 4C reinforcement particles. The amorphous multilayers consist of nonstoichiometric Al xO y, while the nanocrystalline region is comprised of MgO nanograins. The experimental results are discussed in terms of the possible underlying mechanisms at AA/B 4C interfaces.« less

Stepwise verification of bone regeneration using recombinant human bone morphogenetic protein-2 in rat fibula model

PubMed Central

2017-01-01

Objectives The purpose of this study was to introduce our three experiments on bone morphogenetic protein (BMP) and its carriers performed using the critical sized segmental defect (CSD) model in rat fibula and to investigate development of animal models and carriers for more effective bone regeneration. Materials and Methods For the experiments, 14, 16, and 24 rats with CSDs on both fibulae were used in Experiments 1, 2, and 3, respectively. BMP-2 with absorbable collagen sponge (ACS) (Experiments 1 and 2), autoclaved autogenous bone (AAB) and fibrin glue (FG) (Experiment 3), and xenogenic bone (Experiment 2) were used in the experimental groups. Radiographic and histomorphological evaluations were performed during the follow-up period of each experiment. Results Significant new bone formation was commonly observed in all experimental groups using BMP-2 compared to control and xenograft (porcine bone) groups. Although there was some difference based on BMP carrier, regenerated bone volume was typically reduced by remodeling after initially forming excessive bone. Conclusion BMP-2 demonstrates excellent ability for bone regeneration because of its osteoinductivity, but efficacy can be significantly different depending on its delivery system. ACS and FG showed relatively good bone regeneration capacity, satisfying the essential conditions of localization and release-control when used as BMP carriers. AAB could not provide release-control as a BMP carrier, but its space-maintenance role was remarkable. Carriers and scaffolds that can provide sufficient support to the BMP/carrier complex are necessary for large bone defects, and AAB is thought to be able to act as an effective scaffold. The CSD model of rat fibula is simple and useful for initial estimate of bone regeneration by agents including BMPs. PMID:29333367

Humic Acid Reduction by Propionibacterium freudenreichii and Other Fermenting Bacteria

PubMed Central

Benz, Marcus; Schink, Bernhard; Brune, Andreas

1998-01-01

Iron-reducing bacteria have been reported to reduce humic acids and low-molecular-weight quinones with electrons from acetate or hydrogen oxidation. Due to the rapid chemical reaction of amorphous ferric iron with the reduced reaction products, humic acids and low-molecular-weight redox mediators may play an important role in biological iron reduction. Since many anaerobic bacteria that are not able to reduce amorphous ferric iron directly are known to transfer electrons to other external acceptors, such as ferricyanide, 2,6-anthraquinone disulfonate (AQDS), or molecular oxygen, we tested several physiologically different species of fermenting bacteria to determine their abilities to reduce humic acids. Propionibacterium freudenreichii, Lactococcus lactis, and Enterococcus cecorum all shifted their fermentation patterns towards more oxidized products when humic acids were present; P. freudenreichii even oxidized propionate to acetate under these conditions. When amorphous ferric iron was added to reoxidize the electron acceptor, humic acids were found to be equally effective when they were added in substoichiometric amounts. These findings indicate that in addition to iron-reducing bacteria, fermenting bacteria are also capable of channeling electrons from anaerobic oxidations via humic acids towards iron reduction. This information needs to be considered in future studies of electron flow in soils and sediments. PMID:9797315

Importance of lactic acid bacteria in Asian fermented foods

PubMed Central

2011-01-01

Lactic acid bacteria play important roles in various fermented foods in Asia. Besides being the main component in kimchi and other fermented foods, they are used to preserve edible food materials through fermentation of other raw-materials such as rice wine/beer, rice cakes, and fish by producing organic acids to control putrefactive microorganisms and pathogens. These bacteria also provide a selective environment favoring fermentative microorganisms and produce desirable flavors in various fermented foods. This paper discusses the role of lactic acid bacteria in various non-dairy fermented food products in Asia and their nutritional and physiological functions in the Asian diet. PMID:21995342

Regulation of Pseudomonas aeruginosa chemotaxis by the nitrogen source.

PubMed Central

Craven, R; Montie, T C

1985-01-01

The regulation of amino acid chemotaxis by nitrogen was investigated in the gram-negative bacterium Pseudomonas aeruginosa. The quantitative capillary tube technique was used to measure chemotactic responses of bacteria to spatial gradients of amino acids and other attractants. Chemotaxis toward serine, arginine, and alpha-aminoisobutyrate was sharply dependent on the form in which nitrogen was presented to the bacteria. Bacteria grown on mineral salts-succinate with potassium nitrate gave responses to amino acids that were 2 to 3 times those of cells grown on ammonium sulfate and 10 to 20 times those of cells grown in mineral salts-succinate with Casamino Acids as the nitrogen source. A combination of ammonium sulfate and glutamate was as effective as Casamino Acids in depressing serine taxis. The threshold concentration for alpha-aminoisobutyrate taxis was consistently lower in nitrate-grown bacteria than in ammonia-grown bacteria. Responsiveness to sodium succinate, however, was not subject to regulation by nitrogen, and glucose chemotaxis was inhibited, rather than enhanced, in nitrate-grown bacteria. These results indicate that chemotaxis of P. aeruginosa toward amino acids is subject to regulation by nitrogen and that this regulation probably is expressed at the level of the chemoreceptors or transducers. PMID:3932326

Lactic acid bacteria found in fermented fish in Thailand.

PubMed

Tanasupawat, Somboon; Okada, Sanae; Komagata, Kazuo

1998-06-01

Forty-seven strains of homofermentative rod-shaped and 5 heterofermentative sphere-shaped lactic acid bacteria were isolated from 4 kinds of fermented fish (pla-ra, pla-chom, kung-chom, and hoi-dong) in Thailand. These bacteria were separated into four groups by phenotypic and chemotaxonomic characteristics, including fluorometric DNA-DNA hybridization. Five strains (Group I) contained meso-diaminopimelic acid in the cell wall. Four strains were identified as Lactobacillus pentosus, and one strain was L. plantarum. Tested strains of this group produced DL-lactic acid. The rest of the rod-shaped bacteria, 23 strains (Group II) and 19 strains (Group III), lacked meso-diaminopimelic acid in the cell wall and were identified as L. farciminis and Lactobacillus species, respectively. The tested strains of these groups produced L-lactic acid. The amount of cellular fatty acids of C16:0 and C18:1, and the DNA base compositions were significant for differentiating the strains in Groups II and III. Five strains of cocci in chains (Group IV) produced gas from glucose. The tested strains of this group produced d-lactic acid. They were identified as a Leuconostoc species. The distribution of these bacteria in fermented fish in Thailand is discussed.

Wind profiling for a coherent wind Doppler lidar by an auto-adaptive background subtraction approach.

PubMed

Wu, Yanwei; Guo, Pan; Chen, Siying; Chen, He; Zhang, Yinchao

2017-04-01

Auto-adaptive background subtraction (AABS) is proposed as a denoising method for data processing of the coherent Doppler lidar (CDL). The method is proposed specifically for a low-signal-to-noise-ratio regime, in which the drifting power spectral density of CDL data occurs. Unlike the periodogram maximum (PM) and adaptive iteratively reweighted penalized least squares (airPLS), the proposed method presents reliable peaks and is thus advantageous in identifying peak locations. According to the analysis results of simulated and actually measured data, the proposed method outperforms the airPLS method and the PM algorithm in the furthest detectable range. The proposed method improves the detection range approximately up to 16.7% and 40% when compared to the airPLS method and the PM method, respectively. It also has smaller mean wind velocity and standard error values than the airPLS and PM methods. The AABS approach improves the quality of Doppler shift estimates and can be applied to obtain the whole wind profiling by the CDL.

No association between alcohol supplementation and autoantibodies to DNA damage in postmenopausal women in a controlled feeding study.

PubMed

Mahabir, S; Baer, D J; Johnson, L L; Frenkel, K; Dorgan, J F; Cambell, W; Hartman, T J; Clevidence, B; Albanes, D; Judd, J T; Taylor, P R

2005-08-01

Alcohol consumption is linked to increased breast cancer risk. Since oestrogens increase breast cancer risk, possibly through oxidative damage, and we have shown that alcohol consumption increases serum oestrogens, we tested whether moderate alcohol supplementation increased oxidative DNA damage among healthy postmenopausal women not on hormone replacement therapy in a randomized controlled crossover study. We used serum 5-hydroxymethyl-2-deoxyuridine (5-HMdU) autoantibodies (aAbs) as a marker of oxidative DNA damage. The results showed no evidence for increased or decreased levels of oxidative DNA damage among women who consumed 15 g or 30 g alcohol per day for 8 weeks compared with women in the 0 g alcohol group. We conclude that among healthy women, it is possible that an 8-week trial of moderate alcohol supplementation might be too short to make enough 5-HMdU aAbs to compare differences by alcohol dose. In future studies, a panel of biomarkers for DNA damage should be used.

A first principles approach to magnetic and optical properties in single-layer graphene sandwiched between boron nitride monolayers

NASA Astrophysics Data System (ADS)

Das, Ritwika; Chowdhury, Suman; Jana, Debnarayan

2015-07-01

The dependence of the stability of single-layer graphene (SLG) sandwiched between hexagonal boron nitride bilayers (h-BN) has been described and investigated for different types of stacking in order to provide the fingerprint of the stacking order which affects the optical properties of such trilayer systems. Considering the four stacking models AAA-, AAB-, ABA-, and ABC-type stacking, the static dielectric functions (in case of parallel polarizations) for AAB-type stacking possesses maximum values, and minimum values are noticed for AAA. However, AAA-type stacking structures contribute the maximum magnetic moment while vanishing magnetic moments are observed for ABA and ABC stacking. The observed optical anisotropy and magnetic properties of these trilayer heterostructures (h-BN/SLG/h-BN) can be understood from the crystallographic stacking order and inherent crystal lattice symmetry. These optical and magnetic results suggest that the h-BN/SLG/h-BN could provide a viable route to graphene-based opto-electronic and spintronic devices.

In vaginal fluid, bacteria associated with bacterial vaginosis can be suppressed with lactic acid but not hydrogen peroxide

PubMed Central

2011-01-01

Background Hydrogen peroxide (H2O2) produced by vaginal lactobacilli is generally believed to protect against bacteria associated with bacterial vaginosis (BV), and strains of lactobacilli that can produce H2O2 are being developed as vaginal probiotics. However, evidence that led to this belief was based in part on non-physiological conditions, antioxidant-free aerobic conditions selected to maximize both production and microbicidal activity of H2O2. Here we used conditions more like those in vivo to compare the effects of physiologically plausible concentrations of H2O2 and lactic acid on a broad range of BV-associated bacteria and vaginal lactobacilli. Methods Anaerobic cultures of seventeen species of BV-associated bacteria and four species of vaginal lactobacilli were exposed to H2O2, lactic acid, or acetic acid at pH 7.0 and pH 4.5. After two hours, the remaining viable bacteria were enumerated by growth on agar media plates. The effect of vaginal fluid (VF) on the microbicidal activities of H2O2 and lactic acid was also measured. Results Physiological concentrations of H2O2 (< 100 μM) failed to inactivate any of the BV-associated bacteria tested, even in the presence of human myeloperoxidase (MPO) that increases the microbicidal activity of H2O2. At 10 mM, H2O2 inactivated all four species of vaginal lactobacilli but only one of seventeen species of BV-associated bacteria. Moreover, the addition of just 1% vaginal fluid (VF) blocked the microbicidal activity of 1 M H2O2. In contrast, lactic acid at physiological concentrations (55-111 mM) and pH (4.5) inactivated all the BV-associated bacteria tested, and had no detectable effect on the vaginal lactobacilli. Also, the addition of 10% VF did not block the microbicidal activity of lactic acid. Conclusions Under optimal, anaerobic growth conditions, physiological concentrations of lactic acid inactivated BV-associated bacteria without affecting vaginal lactobacilli, whereas physiological concentrations of H2O2 produced no detectable inactivation of either BV-associated bacteria or vaginal lactobacilli. Moreover, at very high concentrations, H2O2 was more toxic to vaginal lactobacilli than to BV-associated bacteria. On the basis of these in vitro observations, we conclude that lactic acid, not H2O2, is likely to suppress BV-associated bacteria in vivo. PMID:21771337

[Metabolic pattern of pig hindgut bacteria on aromatic amino acids by an in vitro fermentation method].

PubMed

Ma, Meilei; He, Xiangyu; Zhu, Weiyun

2016-11-04

This experiment was conducted to study different metabolic patterns of pig hindgut bacteria on aromatic amino acids by an in vitro fermentation method. Ileum, cecum and colon chyme in Duroc, Landrace and Yorkshire goods hybridization pigs were taken as inoculum. The single aromatic amino acid concentration was kept 10 mmol/L in fermentation flask. Then the fermentation flask was incubated at 37℃ for 24 h. Gas production was measured at 4, 8, 12, 16 and 24 h, and samples of fermentation collected at 0 h and 24 h were used to measure ammonia nitrogen NH3-N and microbial crude protein (MCP). Denaturing gradient gel electrophoresis (DGGE) and real-time PCR were used to monitor and quantify the development of bacteria community in zymotic fluid.[ The concentrations of NH3-N and MCP were significantly affected by aromatic amino acids and intestinal segments (P<0.01). Intestinal segments also affected gas production (GP) significantly (P0.01). NH3-N, MCP and GP were affected by interaction of aromatic amino acids and intestinal segments. DGGE analysis showed bacteria of aromatic amino acids shared amount of bands together, especially similarity analysis of DGGE profile of Phe and Tyr in ileum, Tyr and Trp in colon were 87.9% and 80.5% separately. Shannon diversity indices analysis revealed that aromatic amino acids in cecum and colon varied significantly (P<0.05). Real-time PCR results showed that the quantity of total bacteria were affected by aromatic amino acids and intestinal segments significantly (P<0.05). The potential as proportion of different aromatic amino acids are different. Compared with Trp and Phe, the diversity of bacteria utilizing Tyr in cecum or colon is low; compared with Tyr and Trp, a large number of Phe participated in synthesizing bacteria.The fermentation pattern of specific aromatic amino acids in different intestinal segment was unique. Compared with ileum and cecum, much more aromatic amino acids participated in the synthesis of bacteria in colon.

Preservation of acidified cucumbers with a combination of fumaric acid and cinnamaldehyde that target lactic acid bacteria and yeasts

USDA-ARS?s Scientific Manuscript database

The naturally occurring compound, fumaric acid, was evaluated as a potential preservative for the long-term storage of cucumbers. Fumaric acid inhibited growth of lactic acid bacteria (LAB) in an acidified cucumber juice medium model system resembling conditions that could allow preservation of cucu...

The Mm-Wave Rotational Spectrum of Glycolic Acid

NASA Astrophysics Data System (ADS)

Kisiel, Zbigniew; Pszczółkowski, Lech; Białkowska-Jaworska, Ewa; Charnley, Steven B.

2014-06-01

Glycolic acid, HOCH_2COOH is the simplest α-hydroxy acid. It is as yet undetected in the interstellar medium, but is known to be present in carbonaceous meteorites and in residues from UV-photolysed interstellar ice analogue mixtures. Prior rotational spectroscopy has been carried out up to 40 GHz for the main, SSC conformer, Presently we report the analysis of the rotational spectrum of glycolic acid on the basis of broadband measurements performed up to 318 GHz, and updated spectroscopic constants for the ground state and the first two excited states of the low-frequency ν21 torsional mode. We have used the AABS package to assign multiple further excited vibrational states of the SSC conformer. In particular, we have been able to assign the highly perturbed triad of ν14, ν20 and 3ν21 states. The triad has been fitted down to experimental accuracy with a coupled fit, which allowed us to pin down the hitherto elusive frequency of the ν21 mode. The experimental results make an interesting comparison with those of anharmonic force field calculations. We have also been able to extend the measurements for the AAT conformer. C.E.Blom, A.Bauder, Chem. Phys. Lett., 82, 492 (1981), J. Am. Chem. Soc., 104, 2993 (1982). H.Hasegawa, O.Ohashi, I.Yamaguchi, J. Mol. Spectrosc., 82, 205 (1982). P.D.Godfrey, F.M.Rodgers, R.D.Brown, J. Am. Chem. Soc., 119, 2232 (1997).

Screening of plant extracts for antimicrobial activity against bacteria and yeasts with dermatological relevance.

PubMed

Weckesser, S; Engel, K; Simon-Haarhaus, B; Wittmer, A; Pelz, K; Schempp, C M

2007-08-01

There is cumulative resistance against antibiotics of many bacteria. Therefore, the development of new antiseptics and antimicrobial agents for the treatment of skin infections is of increasing interest. We have screened six plant extracts and isolated compounds for antimicrobial effects on bacteria and yeasts with dermatological relevance. The following plant extracts have been tested: Gentiana lutea, Harpagophytum procumbens, Boswellia serrata (dry extracts), Usnea barbata, Rosmarinus officinalis and Salvia officinalis (supercritical carbon dioxide [CO2] extracts). Additionally, the following characteristic plant substances were tested: usnic acid, carnosol, carnosic acid, ursolic acid, oleanolic acid, harpagoside, boswellic acid and gentiopicroside. The extracts and compounds were tested against 29 aerobic and anaerobic bacteria and yeasts in the agar dilution test. U. barbata-extract and usnic acid were the most active compounds, especially in anaerobic bacteria. Usnea CO2-extract effectively inhibited the growth of several Gram-positive bacteria like Staphylococcus aureus (including methicillin-resistant strains - MRSA), Propionibacterium acnes and Corynebacterium species. Growth of the dimorphic yeast Malassezia furfur was also inhibited by Usnea-extract. Besides the Usnea-extract, Rosmarinus-, Salvia-, Boswellia- and Harpagophytum-extracts proved to be effective against a panel of bacteria. It is concluded that due to their antimicrobial effects some of the plant extracts may be used for the topical treatment of skin disorders like acne vulgaris and seborrhoic eczema.

Isolation of lactic acid bacteria with potential protective culture characteristics from fruits

NASA Astrophysics Data System (ADS)

Hashim, Nurul Huda; Sani, Norrakiah Abdullah

2015-09-01

Lactic acid bacteria are also known as beneficial microorganisms abundantly found in fermented food products. In this study, lactic acid bacteria were isolated from fresh cut fruits obtained from local markets. Throughout the isolation process from 11 samples of fruits, 225 presumptive lactic acid bacteria were isolated on MRS agar medium. After catalase and oxidase tests, 149 resulted to fit the characteristics of lactic acid bacteria. Further identification using Gram staining was conducted to identify the Gram positive bacteria. After this confirmation, the fermentation characteristics of these isolates were identified. It was found that 87 (58.4%) isolates were heterofermentative, while the rest of 62 (41.6%) are homofermentative lactic acid bacteria. Later, all these isolates were investigated for the ability to inhibit growth of Staphylococcus aureus using agar spot assay method. Seven (4.7%) isolates showed strong antagonistic capacity, while 127 (85.2%) and 8 (5.4%) isolates have medium and weak antagonistic capacity, respectively. The other 7 (4.7%) isolates indicated to have no antagonistic effect on S. aureus. Results support the potential of LAB isolated in this study which showed strong antagonistic activity against S. aureus may be manipulated to become protective cultures in food products. While the homofermentative or heterofermentative LAB can be utilized in fermentation of food and non-food products depending on the by-products required during the fermentation.

A Glutamic Acid-Producing Lactic Acid Bacteria Isolated from Malaysian Fermented Foods

PubMed Central

Zareian, Mohsen; Ebrahimpour, Afshin; Bakar, Fatimah Abu; Mohamed, Abdul Karim Sabo; Forghani, Bita; Ab-Kadir, Mohd Safuan B.; Saari, Nazamid

2012-01-01

l-glutamaic acid is the principal excitatory neurotransmitter in the brain and an important intermediate in metabolism. In the present study, lactic acid bacteria (218) were isolated from six different fermented foods as potent sources of glutamic acid producers. The presumptive bacteria were tested for their ability to synthesize glutamic acid. Out of the 35 strains showing this capability, strain MNZ was determined as the highest glutamic-acid producer. Identification tests including 16S rRNA gene sequencing and sugar assimilation ability identified the strain MNZ as Lactobacillus plantarum. The characteristics of this microorganism related to its glutamic acid-producing ability, growth rate, glucose consumption and pH profile were studied. Results revealed that glutamic acid was formed inside the cell and excreted into the extracellular medium. Glutamic acid production was found to be growth-associated and glucose significantly enhanced glutamic acid production (1.032 mmol/L) compared to other carbon sources. A concentration of 0.7% ammonium nitrate as a nitrogen source effectively enhanced glutamic acid production. To the best of our knowledge this is the first report of glutamic acid production by lactic acid bacteria. The results of this study can be further applied for developing functional foods enriched in glutamic acid and subsequently γ-amino butyric acid (GABA) as a bioactive compound. PMID:22754309

10-oxo-12(Z)-octadecenoic acid, a linoleic acid metabolite produced by gut lactic acid bacteria, potently activates PPARγ and stimulates adipogenesis

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

Goto, Tsuyoshi, E-mail: tgoto@kais.kyoto-u.ac.jp; Research Unit for Physiological Chemistry, The Center for the Promotion of Interdisciplinary Education and Research, Kyoto University; Kim, Young-Il

2015-04-17

Our previous study has shown that gut lactic acid bacteria generate various kinds of fatty acids from polyunsaturated fatty acids such as linoleic acid (LA). In this study, we investigated the effects of LA and LA-derived fatty acids on the activation of peroxisome proliferator-activated receptors (PPARs) which regulate whole-body energy metabolism. None of the fatty acids activated PPARδ, whereas almost all activated PPARα in luciferase assays. Two fatty acids potently activated PPARγ, a master regulator of adipocyte differentiation, with 10-oxo-12(Z)-octadecenoic acid (KetoA) having the most potency. In 3T3-L1 cells, KetoA induced adipocyte differentiation via the activation of PPARγ, and increasedmore » adiponectin production and insulin-stimulated glucose uptake. These findings suggest that fatty acids, including KetoA, generated in gut by lactic acid bacteria may be involved in the regulation of host energy metabolism. - Highlights: • Most LA-derived fatty acids from gut lactic acid bacteria potently activated PPARα. • Among tested fatty acids, KetoA and KetoC significantly activated PPARγ. • KetoA induced adipocyte differentiation via the activation of PPARγ. • KetoA enhanced adiponectin production and glucose uptake during adipogenesis.« less

Electron transport chains of lactic acid bacteria - walking on crutches is part of their lifestyle

PubMed Central

Brooijmans, Rob; Hugenholtz, Jeroen

2009-01-01

A variety of lactic acid bacteria contain rudimentary electron transport chains that can be reconstituted by the addition of heme and menaquinone to the growth medium. These activated electron transport chains lead to higher biomass production and increased robustness, which is beneficial for industrial applications, but a major concern when dealing with pathogenic lactic acid bacteria. PMID:20948651

How Bacterial Pathogens Eat Host Lipids: Implications for the Development of Fatty Acid Synthesis Therapeutics*

PubMed Central

Yao, Jiangwei; Rock, Charles O.

2015-01-01

Bacterial type II fatty acid synthesis (FASII) is a target for the development of novel therapeutics. Bacteria incorporate extracellular fatty acids into membrane lipids, raising the question of whether pathogens use host fatty acids to bypass FASII and defeat FASII therapeutics. Some pathogens suppress FASII when exogenous fatty acids are present to bypass FASII therapeutics. FASII inhibition cannot be bypassed in many bacteria because essential fatty acids cannot be obtained from the host. FASII antibiotics may not be effective against all bacteria, but a broad spectrum of Gram-negative and -positive pathogens can be effectively treated with FASII inhibitors. PMID:25648887

Production of Value-added Products by Lactic Acid Bacteria

USDA-ARS?s Scientific Manuscript database

Lactic acid bacteria (LAB) are a group of facultative anaerobic, catalase negative, nonmotile and nonsporeforming–Gram positive bacteria. Most LAB utilize high energy C sources including monomer sugars to produce energy to maintain cellular structure and function. This anaerobic fermentation proce...

Dietary influence of kefir on microbial activities in the mouse bowel.

PubMed

Marquina, Domingo; Santos, A; Corpas, I; Muñoz, J; Zazo, J; Peinado, J M

2002-01-01

In this work the microflora present in kefir, a fermented milk product, was studied together with the effect of kefir administration on different groups of indigenous bacteria of mouse bowel. Kefir microflora was composed of lactic acid bacteria, acetic acid bacteria and yeasts. Yeast population was composed of Saccharomyces cerevisiae, S. unisporus, Candida kefir, Kluyveromyces marxianus and K. lactis. The streptococci levels in kefir treated mice increased by 10-fold and the levels of sulfite-reducing clostridia decreased by 100-fold. The number of lactic acid bacteria increased significantly. The administration of kefir significantly increased the lactic acid bacteria counts in the mucosa of the bowel. Ingestion of kefir specifically lowered microbial populations of Enterobacteriaceae and clostridia. This is the first long-term study about the effects of the kefir administration on the intestinal microflora of mice.

Scientific and Organizational Awards | NREL

Science.gov Websites

Rehman, Fan Zhang, Michael Evzelman, Regan Zane, Kandler Smith, and Dragan Maksimovic 2015 Best Paper organizations. American Association of Blacks in Energy (AABE) 2005 Chairman's Cup Syl Morgan-Smith American Metropolitan Denver 2006 Outstanding Community Service Award Syl Morgan-Smith World Renewable Energy Congress

Fermented probiotic beverages based on acid whey.

PubMed

Skryplonek, Katarzyna; Jasińska, Małgorzata

2015-01-01

Production of fermented probiotic beverages can be a good method for acid whey usage. The obtained products combine a high nutritional value of whey with health benefits claimed for probiotic bacteria. The aim of the study was to define quality properties of beverages based on fresh acid whey and milk with addition of buttermilk powder or sweet whey powder. Samples were inoculated with two strains of commercial probiotic cultures: Lactobacillus acidophilus La-5 or Bifidobacterium animalis Bb-12. After fermentation, samples were stored at refrigerated conditions. After 1, 4, 7, 14 and 21 days sensory characteristics, hardness, acetaldehyde content, titratable acidity, pH acidity and count of bacteria cells were evaluated. Throughout all storage period, the number of bacteria was higher than 8 log cfu/ml in the all samples. Beverages with La-5 strain had higher hardness and acidity, whilst samples with Bb-12 contained more acetaldehyde. Samples with buttermilk powder had better sensory properties than with sweet whey powder. Obtained products made of acid whey combined with milk and fortified with buttermilk powder or sweet whey powder, are good medium for growth and survival of examined probiotic bacteria strains. The level of bacteria was sufficient to provide health benefits to consumers.

Heme and menaquinone induced electron transport in lactic acid bacteria.

PubMed

Brooijmans, Rob; Smit, Bart; Santos, Filipe; van Riel, Jan; de Vos, Willem M; Hugenholtz, Jeroen

2009-05-29

For some lactic acid bacteria higher biomass production as a result of aerobic respiration has been reported upon supplementation with heme and menaquinone. In this report, we have studied a large number of species among lactic acid bacteria for the existence of this trait. Heme- (and menaquinone) stimulated aerobic growth was observed for several species and genera of lactic acid bacteria. These include Lactobacillus plantarum, Lactobacillus rhamnosus, Lactobacilllus brevis, Lactobacillus paralimentarius, Streptococcus entericus and Lactococcus garviae. The increased biomass production without further acidification, which are respiration associated traits, are suitable for high-throughput screening as demonstrated by the screening of 8000 Lactococcus lactis insertion mutants. Respiration-negative insertion-mutants were found with noxA, bd-type cytochrome and menaquinol biosynthesis gene-disruptions. Phenotypic screening and in silico genome analysis suggest that respiration can be considered characteristic for certain species. We propose that the cyd-genes were present in the common ancestor of lactic acid bacteria, and that multiple gene-loss events best explains the observed distribution of these genes among the species.

Bacteria and Acidic Drainage from Coal Refuse: Inhibition by Sodium Lauryl Sulfate and Sodium Benzoate

PubMed Central

Dugan, Patrick R.; Apel, William A.

1983-01-01

The application of an aqueous solution of sodium lauryl sulfate and sodium benzoate to the surface of high-sulfur coal refuse resulted in the inhibition of iron-and sulfur-oxidizing chemoautotrophic bacteria and in the decrease of acidic drainage from the refuse, suggesting that acid drainage can be abated in the field by inhibiting iron- and sulfur-oxidizing bacteria. PMID:16346347

Determination of the gram-positive bacterial content of soils and sediments by analysis of teichoic acid components

NASA Technical Reports Server (NTRS)

Gehron, M. J.; Davis, J. D.; Smith, G. A.; White, D. C.

1984-01-01

Many gram-positive bacteria form substituted polymers of glycerol and ribitol phosphate esters known as teichoic acids. Utilizing the relative specificity of cold concentrated hydrofluoric acid in the hydrolysis of polyphosphate esters it proved possible to quantitatively assay the teichoic acid-derived glycerol and ribitol from gram-positive bacteria added to various soils and sediments. The lipids are first removed from the soils or sediments with a one phase chloroform-methanol extraction and the lipid extracted residue is hydrolyzed with cold concentrated hydrofluoric acid. To achieve maximum recovery of the teichoic acid ribitol, a second acid hydrolysis of the aqueous extract is required. The glycerol and ribitol are then acetylated after neutralization and analyzed by capillary gas-liquid chromatography. This technique together with measures of the total phospholipid, the phospholipid fatty acid, the muramic acid and the hydroxy fatty acids of the lipopolysaccharide lipid A of the gram-negative bacteria makes it possible to describe the community structure environmental samples. The proportion of gram-positive bacteria measured as the teichoic acid glycerol and ribitol is higher in soils than in sediments and increases with depth in both.

Estimation of lactic acid bacterial cell number by DNA quantification.

PubMed

Ishii, Masaki; Matsumoto, Yasuhiko; Sekimizu, Kazuhisa

2018-01-01

Lactic acid bacteria are provided by fermented foods, beverages, medicines, and supplements. Because the beneficial effects of medicines and supplements containing functional lactic acid bacteria are related to the bacterial cell number, it is important to establish a simple method for estimating the total number of lactic acid bacterial cells in the products for quality control. Almost all of the lactic acid bacteria in the products are dead, however, making it difficult to estimate the total number of lactic acid bacterial cells in the products using a standard colony-counting method. Here we estimated the total lactic acid bacterial cell number in samples containing dead bacteria by quantifying the DNA. The number of viable Enterococcus faecalis 0831-07 cells decreased to less than 1 × 10 -8 by 15 min of heat treatment at 80°C. The amount of extracted DNA from heat-treated cells was 78% that of non-heated cells. The number of viable Lactobacillus paraplantarum 11-1 cells decreased to 1 × 10 -4 after 4 days culture. The amount of extracted DNA of the long-cultured cells, however, was maintained at 97%. These results suggest that cell number of lactic acid bacteria killed by heat-treatment or long-term culture can be estimated by DNA quantification.

Synergistic antibacterial and antibiofilm efficacy of nisin in combination with p-coumaric acid against food-borne bacteria Bacillus cereus and Salmonella typhimurium.

PubMed

Bag, A; Chattopadhyay, R R

2017-11-01

The aim of the study was to evaluate possible antibacterial and antibiofilm efficacy of a bacteriocin, nisin with two essential oil components linalool and p-coumaric acid in combination against food-borne bacteria Bacillus cereus and Salmonella typhimurium. Their inhibition effects on planktonic cells and preformed biofilms were evaluated using microbroth dilution and checkerboard titration methods. Nisin/p-coumaric acid combination showed synergistic effects against planktonic cells of both the studied bacteria, whereas nisin/linalool combination showed synergistic activity against B. cereus and additive effect against S. typhimurium. In preformed biofilms, nisin by itself failed to show >50% antibiofilm efficacy against both the studied bacteria, but in combination with linalool and p-coumaric acid, it exerted >50% antibiofilm efficacy. On the basis of fractional inhibitory concentration indices values, nisin/p-coumaric acid combination exhibited synergistic antibiofilm activity, whereas nisin/linalool combination showed additive effects against preformed biofilms of studied bacteria. The results provide evidence that p-coumaric acid due to its synergistic interactions with nisin against planktonic cells and biofilms of both Gram-positive and Gram-negative food-borne bacteria enhanced the antibacterial spectrum of nisin, which subsequently may facilitate their use in the food industry. In the present work, synergistic interactions between a bacteriocin, nisin and essential oil component p-coumaric acid on planktonic cells as well as on biofilms of Gram-positive and Gram-negative food-borne bacteria have been reported. The results of this study provide evidence that nisin/p-coumaric acid combination can be considered as a promising source for development of more potent broad spectrum antimicrobial blend for food preservation, which subsequently may facilitate their use in the food industry. To the best of our knowledge, this is the first report of the antibacterial and antibiofilm efficacy of nisin in combination with essential oil components against food-borne bacteria. © 2017 The Society for Applied Microbiology.

Antibacterial Activity of Lactic Acid Bacteria Isolated from Gastrointestinal Tract of “Ayam Kampung” Chicken Against Food Pathogens

NASA Astrophysics Data System (ADS)

Nur Jannah, Siti; Rini Saraswati, Tyas; Handayani, Dwi; Pujiyanto, Sri

2018-05-01

Food borne disease results from ingestion of water and wide variety of food contaminated with pathogenic organisms. The main causes of food borne diseases are bacteria, such as Escherichia coli and Staphylococcus aureus. The objective of this study was to determine antimicrobial activity of lactic acid bacteria (LAB) isolated from local chicken gastrointestinal tract with an emphasis on their probiotic properties. The colonies of bacteria that producing clear zone on MRSA plus 0.5% CaCO3, Gram-positive and catalase-negative were isolated as lactic acid bacteria. Some of the strains (10 isolates) were tested for their ability to inhibit growth of Escherichia coli and Staphylococcus aureus, and for acid pH and bile salt tolerance. The results showed that the all selected isolates producing antimicrobial compounds inhibits the growth of Escherichia coli and Staphylococcus aureus, both in the supernatant and supernatant plus 2M NaOH, and still growing in medium condition with pH 2.0 and 0.1% bile salt. It revealing the potential use of the lactic acid bacteria from chicken gastrointestinal tract for probiotics in food.

Antagonistic effect of chosen lactic acid bacteria strains on Salmonella species in meat and fermented sausages.

PubMed

Gomółka-Pawlicka, M; Uradziński, J

2003-01-01

The aim of this study was to determine of influence of 15 strains of lactic acid bacteria on the growth of 7 Salmonella spp. strains in model set-ups, and in meat and ripened fermented sausages. The investigations were performed within the framework of three alternate stages which differed in respect to the products studied, the number of Lactobacillus spp. strains and, partly, methodological approach. The ratio between lactic acid bacteria and Salmonella strains studied was, depending on the alternate, 1:1, 1:2 and 2:1, respectively. The investigations also covered the water activity (a(w)) and pH of the tested products. The results obtained are shown in 12 figures and suggest that all the lactic acid bacteria strains used within the framework of the model set-ups showed antagonistic effect on all the Salmonella spp. strains. However, these abilities were not observed with respect to some lactic acid bacteria strains in meat and fermented sausage. The temperature and length of the incubation period of sausages, but not a(w) and pH, were found to have a distinct influence on the antagonistic interaction between the bacteria.

[Effect of Gram-negative bacteria on fatty acids].

PubMed

Vuillemin, N; Dupeyron, C; Leluan, G; Bory, J

1981-01-01

The gram-negative bacteria investigated exert various effects on fatty acids. P. aeruginosa and A. calcoaceticus catabolize any of the fatty acids tested. S. marcescens is effective upon all fatty acids excepting butyric acid. The long chain fatty acids only are degraded by E. coli, meanwhile the other fatty acids present a bacteriostatic or bactericidal activity on it. The authors propose a simple and original method for testing the capability of degradation of fatty acids by some bacterial species.

Papers in Warlpiri Grammar: In Memory of Lothar Jagst. Work Papers of SIL-AAB, Series A, Volume 6.

ERIC Educational Resources Information Center

Swartz, Stephen M., Ed.

Five papers on the grammar of Warlpiri, an Australian Aboriginal language, include: "A Tentative Description of Ngardilpa (Warlpiri) Verbs" (Lothar H. Jagst); "Syntactic Structure of Warlpiri Clauses" (Stephen M. Swartz); "A Preliminary Description of Propositional Particles in Warlpiri" (Mary Laughren);…

76 FR 54807 - Submission of OMB Review: Comment Request

Federal Register 2010, 2011, 2012, 2013, 2014

2011-09-02

... Benchmarking Survey Submission of OMB Review: Comment Request The National Endowment for the Arts (NEA) has... the Arts. Title: Annual Arts Benchmarking Survey. OMB Number: New. Frequency: Annually, in years the... Purchasing Services): 0. This request is for clearance of the Annual Arts Benchmarking Survey (AABS) to be...

77 FR 60434 - Ocean Transportation Intermediary License Applicants

Federal Register 2010, 2011, 2012, 2013, 2014

2012-10-03

..., Washington, DC 20573, by telephone at (202) 523-5843 or by email at [email protected] . AAB Logistics, LLC (NVO... Logistics, Inc. (NVO & OFF), 4666 Faries Parkway, Decatur, IL 62526, Officers: Mark D. Schweitzer, Vice... Gurdian, President, Application Type: New NVO & OFF License. J&T Logistics Inc. dba EDI Logistics Group...

How Do They Grow?

ERIC Educational Resources Information Center

Chan, Helen Hsu

2015-01-01

Students' experiences with pattern blocks begin as early as preschool. At that time, they begin to develop an understanding of repetition by alternating the colored shapes to create AB, AAB, or ABC patterns. They experiment with area and symmetry by covering polygonal spaces using the fewest (or the greatest) number of pattern blocks possible or…

Lactic Acid Bacteria Producing Inhibitor of Alpha Glucosidase Isolated from Ganyong (Canna Edulis) and Kimpul (Xanthosoma sagittifolium)

NASA Astrophysics Data System (ADS)

Nurhayati, Rifa; Miftakhussolikhah; Frediansyah, Andri; Lailatul Rachmah, Desy

2017-12-01

Type 2 diabetes is a disease that caused by the failure of insulin secretion by the beta cells of the pancreas and insulin resistance in peripheral levels. One therapy for diabetics is by inhibiting the activity of α-glucosidase. Lactic acid bacteria have the ability to inhibit of α-glucosidase activity. The aims of this research was to isolation and screening of lactic acid bacteria from ganyong tuber (Canna Edulis) and kimpul tuber (Xanthosoma sagittifolium), which has the ability to inhibit the activity of α-glucosidase. Eightteen isolates were identified as lactic acid bacteria and all of them could inhibit the activity of α-glukosidase. The GN 8 isolate was perform the highest inhibition acivity.

Glucose and D-Allulose contained medium to support the growth of lactic acid bacteria

NASA Astrophysics Data System (ADS)

Al-Baarri, A. N.; Legowo, A. M.; Pramono, Y. B.; Sari, D. I.; Pangestika, W.

2018-01-01

Monosaccharide has been known as support agent for the growth of lactic acid bacteria. However the combination among monosaccharides for supporting the living of bacteria has not been understood well. This research was done for analyzing the combination glucose and D-allulose for the growth of Lactobacillus acidophilus and Streptococcus thermophillus. The NaCl medium containing glucose and D-allulose was used to analyse the growth of bacteria. The study showed that glucose and D-allulose have been detected as supportive agent to L. acidophilus and S. thermophillus specifically. As conclusion, glucose and D-allulose supported the growth of lactic acid bacteria equally. This finding might provide the beneficial information for industry to utilize D-allulose as well as glucose.

In Silico Evidence for the Horizontal Transfer of gsiB, a σΒ-Regulated Gene in Gram-Positive Bacteria, to Lactic Acid Bacteria ▿

PubMed Central

Asteri, Ioanna-Areti; Boutou, Effrossyni; Anastasiou, Rania; Pot, Bruno; Vorgias, Constantinos E.; Tsakalidou, Effie; Papadimitriou, Konstantinos

2011-01-01

gsiB, coding for glucose starvation-inducible protein B, is a characteristic member of the σΒ stress regulon of Bacillus subtilis and several other Gram-positive bacteria. Here we provide in silico evidence for the horizontal transfer of gsiB in lactic acid bacteria that are devoid of the σΒ factor. PMID:21421783

Antibacterial Potential of Northeastern Portugal Wild Plant Extracts and Respective Phenolic Compounds

PubMed Central

Ferreira, Isabel C. F. R.; Barros, Lillian; Carvalho, Ana Maria; Soares, Graça; Henriques, Mariana

2014-01-01

The present work aims to assess the antibacterial potential of phenolic extracts, recovered from plants obtained on the North East of Portugal, and of their phenolic compounds (ellagic, caffeic, and gallic acids, quercetin, kaempferol, and rutin), against bacteria commonly found on skin infections. The disk diffusion and the susceptibility assays were used to identify the most active extracts and phenolic compounds. The effect of selected phenolic compounds on animal cells was assessed by determination of cellular metabolic activity. Gallic acid had a higher activity, against gram-positive (S. epidermidis and S. aureus) and gram-negative bacteria (K. pneumoniae) at lower concentrations, than the other compounds. The caffeic acid, also, showed good antibacterial activity against the 3 bacteria used. The gallic acid was effective against the 3 bacteria without causing harm to the animal cells. Gallic and caffeic acid showed a promising applicability as antibacterial agents for the treatment of infected wounds. PMID:24804249

Gastric acid reduction leads to an alteration in lower intestinal microflora

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

Kanno, Takayuki; Matsuki, Takahiro; Oka, Masashi

2009-04-17

To clarify the alterations in lower intestinal microflora induced by gastric acid reduction, the dynamics of 12 major genera or groups of bacteria comprising the microflora in feces and colonic contents were examined by quantitative real-time PCR in proton pump inhibitor-treated rats and in asymptomatic human subjects with hypochlorhydria. In both rat and human experiments, most genera or groups of intestinal microflora (facultative and obligate anaerobes) proliferated by gastric acid reduction, and marked and significant increases in the Lactobacilli group and Veillonella, oropharyngeal bacteria, were observed. In rats, potent gastric acid inhibition led to a marked and significant increase ofmore » intestinal bacteria, including the Bacteroidesfragilis group, while Bifidobacterium, a beneficial bacterial species, remained at a constant level. These results strongly indicate that the gastric acid barrier not only controls the colonization and growth of oropharyngeal bacteria, but also regulates the population and composition of lower intestinal microflora.« less

Characterization of airag collected in Ulaanbaatar, Mongolia with emphasis on isolated lactic acid bacteria.

PubMed

Choi, Suk-Ho

2016-01-01

Airag, alcoholic sour-tasting beverage, has been traditionally prepared by Mongolian nomads who naturally ferment fresh mares' milk. Biochemical and microbiological compositions of airag samples collected in Ulaanbaatar, Mongolia and physiological characteristics of isolated lactic acid bacteria were investigated. Protein composition and biochemical composition were determined using sodium dodecyl sulfate-gel electrophoresis and high performance liquid chromatography, respectively. Lactic acid bacteria were identified based on nucleotide sequence of 16S rRNA gene. Carbohydrate fermentation, acid survival, bile resistance and acid production in skim milk culture were determined. Equine whey proteins were present in airag samples more than caseins. The airag samples contained 0.10-3.36 % lactose, 1.44-2.33 % ethyl alcohol, 1.08-1.62 % lactic acid and 0.12-0.22 % acetic acid. Lactobacillus (L.) helveticus were major lactic acid bacteria consisting of 9 isolates among total 18 isolates of lactic acid bacteria. L. helveticus survived strongly in PBS, pH 3.0 but did not grow in MRS broth containing 0.1 % oxgall. A couple of L. helveticus isolates lowered pH of skim milk culture to less than 4.0 and produced acid up to more than 1.0 %. Highly variable biochemical compositions of the airag samples indicated inconsistent quality due to natural fermentation. Airag with low lactose content should be favorable for nutrition, considering that mares' milk with high lactose content has strong laxative effect. The isolates of L. helveticus which produced acid actively in skim milk culture might have a major role in production of airag.

Review - Lactic acid bacteria in traditional fermented Asian foods.

PubMed

Azam, Mariya; Mohsin, Mashkoor; Ijaz, Hira; Tulain, Ume Ruqia; Ashraf, Muhammad Adnan; Fayyaz, Ahad; Abadeen, Zainul; Kamran, Qindeel

2017-09-01

Lactic acid bacteria play vital roles in various fermented foods in Asia. This paper reviews many types of the world's lactic acid fermented foods and discusses the beneficial effects of lactic acid fermentation of food. The lactic acid bacteria associated with foods now include species of the genera Carnobacterium, Enterococcus, Lactobacillus, Lactococcus, Leuconostoc, Oenococcus, Pediococcus, Streptococcus, Tetragenococcus, Vagococcus and Weissella. Lactic acid bacteria (LAB) are involved in many fermentation processes of Asian traditional foods, demonstrating their profound effects on improving food quality and food safety. During the past few decades' interest has arisen in the use of the varied antagonistic activities of LAB to extent the shelf-life of protein-rich products such as meats and fish. This review article outlines the main types of LAB fermentation as well as their typical fermented foods such as idli, kishk, sauerkraut, koumiss, Suan-tsai, stinky tofu, Chinese sausage and kefir. The roles of LAB and the reasons for their common presence are also discussed.

Heme and menaquinone induced electron transport in lactic acid bacteria

PubMed Central

Brooijmans, Rob; Smit, Bart; Santos, Filipe; van Riel, Jan; de Vos, Willem M; Hugenholtz, Jeroen

2009-01-01

Background For some lactic acid bacteria higher biomass production as a result of aerobic respiration has been reported upon supplementation with heme and menaquinone. In this report, we have studied a large number of species among lactic acid bacteria for the existence of this trait. Results Heme- (and menaquinone) stimulated aerobic growth was observed for several species and genera of lactic acid bacteria. These include Lactobacillus plantarum, Lactobacillus rhamnosus, Lactobacilllus brevis, Lactobacillus paralimentarius, Streptococcus entericus and Lactococcus garviae. The increased biomass production without further acidification, which are respiration associated traits, are suitable for high-throughput screening as demonstrated by the screening of 8000 Lactococcus lactis insertion mutants. Respiration-negative insertion-mutants were found with noxA, bd-type cytochrome and menaquinol biosynthesis gene-disruptions. Phenotypic screening and in silico genome analysis suggest that respiration can be considered characteristic for certain species. Conclusion We propose that the cyd-genes were present in the common ancestor of lactic acid bacteria, and that multiple gene-loss events best explains the observed distribution of these genes among the species. PMID:19480672

Chemical compositions and antibacterial activity of extracts obtained from the inflorescences of Cirsium canum (L.) all.

PubMed

Kozyra, Małgorzata; Biernasiuk, Anna; Malm, Anna; Chowaniec, Marcin

2015-01-01

The aim of this study was to investigate phenolic acids and flavonoids in methanolic, dichloromethane, acetone and ethyl acetate extracts and fractions from inflorescences of Cirsium canum (L.). RP-HPLC analysis enabled identification of the following: chlorogenic acid, caffeic acid, p-coumaric acid, protocatechuic acid, p-hydroxybenzoic acid, vanillic acid, syringic acid, trans-cinnamic acid, luteolin-7-glucoside, apigenin-7-glucoside, kaempferol-3-glucoside, linarin, apigenin, rutoside, luteolin and kaempferol. The antimicrobial activity of tested extracts was determined in vitro against reference microorganisms, including bacteria or fungi, belonging to yeasts. Our data showed that the tested extracts had no influence on the growth of the reference strains of Gram-negative bacteria and yeasts belonging to Candida spp. Among them, the fractions possessed the highest activity against Gram-positive bacteria, especially Streptococcus aureus and Streptococcus pneumoniae belonging to pathogens and Streptococcus epidermidis, Bacilluscereus and Bacillus subtilis belonging to opportunistic microorganisms.

Genomics of Probiotic Bacteria

NASA Astrophysics Data System (ADS)

O'Flaherty, Sarah; Goh, Yong Jun; Klaenhammer, Todd R.

Probiotic bacteria from the Lactobacillus and Bifidobacterium species belong to the Firmicutes and the Actinobacteria phylum, respectively. Lactobacilli are members of the lactic acid bacteria (LAB) group, a broadly defined family of microorganisms that ferment various hexoses into primarily lactic acid. Lactobacilli are typically low G + C gram-positive species which are phylogenetically diverse, with over 100 species documented to date. Bifidobacteria are heterofermentative, high G + C content bacteria with about 30 species of bifidobacteria described to date.

Metabolic interactions in methanogenic and sulfate-reducing bioreactors.

PubMed

Stams, A J M; Plugge, C M; de Bok, F A M; van Houten, B H G W; Lens, P; Dijkman, H; Weijma, J

2005-01-01

In environments where the amount of electron acceptors is insufficient for complete breakdown of organic matter, methane is formed as the major reduced end product. In such methanogenic environments organic acids are degraded by syntrophic consortia of acetogenic bacteria and methanogenic archaea. Hydrogen consumption by methanogens is essential for acetogenic bacteria to convert organic acids to acetate and hydrogen. Several syntrophic cocultures growing on propionate and butyrate have been described. These syntrophic fatty acid-degrading consortia are affected by the presence of sulfate. When sulfate is present sulfate-reducing bacteria compete with methanogenic archaea for hydrogen and acetate, and with acetogenic bacteria for propionate and butyrate. Sulfate-reducing bacteria easily outcompete methanogens for hydrogen, but the presence of acetate as carbon source may influence the outcome of the competition. By contrast, acetoclastic methanogens can compete reasonably well with acetate-degrading sulfate reducers. Sulfate-reducing bacteria grow much faster on propionate and butyrate than syntrophic consortia.

Isolation of oxalotrophic bacteria associated with Varroa destructor mites.

PubMed

Maddaloni, M; Pascual, D W

2015-11-01

Bacteria associated with varroa mites were cultivated and genotyped by 16S RNA. Under our experimental conditions, the cultivable bacteria were few in number, and most of them proved to be fastidious to grow. Cultivation with seven different media under O2 /CO2 conditions and selection for colony morphology yielded a panel of species belonging to 13 different genera grouped in two different phyla, proteobacteria and actinobacteria. This study identified one species of actinobacteria that is a known commensal of the honey bee. Some isolates are oxalotrophic, a finding that may carry ramifications into the use of oxalic acid to control the number of phoretic mites in the managed colonies of honey bees. Oxalic acid, legally or brevi manu, is widely used to control phoretic Varroa destructor mites, a major drive of current honey bees' colony losses. Unsubstantiated by sanctioned research are rumours that in certain instances oxalic acid is losing efficacy, forcing beekeepers to increase the frequency of treatments. This investigation fathoms the hypothesis that V. destructor associates with bacteria capable of degrading oxalic acid. The data show that indeed oxalotrophy, a rare trait among bacteria, is common in bacteria that we isolated from V. destructor mites. This finding may have ramifications in the use of oxalic acid as a control agent. © 2015 The Society for Applied Microbiology.

Lactic acid bacteria and yeasts associated with spontaneous fermentations during the production of sour cassava starch in Brazil.

PubMed

Lacerda, Inayara C A; Miranda, Rose L; Borelli, Beatriz M; Nunes, Alvaro C; Nardi, Regina M D; Lachance, Marc-André; Rosa, Carlos A

2005-11-25

Sour cassava starch is a traditional fermented food used in the preparation of fried foods and baked goods such as traditional cheese breads in Brazil. Thirty samples of sour cassava starch were collected from two factories in the state of Minas Gerais. The samples were examined for the presence of lactic acid bacteria, yeasts, mesophilic microorganisms, Bacillus cereus and faecal coliforms. Lactic acid bacteria and yeasts isolates were identified by biochemical tests, and the identities were confirmed by molecular methods. Lactobacillus plantarum and Lactobacillus fermentum were the prevalent lactic acid bacteria in product from both factories, at numbers between 6.0 and 9.0 log cfu g(-)(1). Lactobacillus perolans and Lactobacillus brevis were minor fractions of the population. Galactomyces geothricum and Issatchenkia sp. were the prevalent yeasts at numbers of 5.0 log cfu g(-)(1). A species similar to Candida ethanolica was frequently isolated from one factory. Mesophilic bacteria and amylolytic microorganisms were recovered in high numbers at all stages of the fermentation. B. cereus was found at low numbers in product at both factories. The spontaneous fermentations associated with the production of sour cassava starch involve a few species of lactic acid bacteria at high numbers and a variety of yeasts at relatively low numbers.

Antagonistic effect of chosen lactic acid bacteria strains on Yersinia enterocolitica species in model set-ups, meat and fermented sausages.

PubMed

Gomółka-Pawlicka, M; Uradziński, J

2003-01-01

The present study was aimed at determining the influence of 15 strains of lactic acid bacteria on the growth of 8 Yersinia enterocolitica strains in model set-ups, and in meat and ageing fermented sausages. The investigations were performed within the framework of three alternate stages which differed in respect to the products studied, the number of Lactobacillus sp. strains and, partly, methodological approach. The ratio between lactic acid bacteria and Yersinia enterocolitica strains studied was, depending on the variant of experiment, 1:1, 1:2 and 2:1, respectively. The study also considered water activity (aw) and pH of the products investigated. The results suggest that all the lactic acid bacteria strains used within the framework of the model set-ups had antagonistic effect on all the Salmonella sp. strains. However, this ability was not observed with respect to of tested lactic acid bacteria strains in meat and fermented sausage. This ability was possessed by one of the strains investigated--Lactobacillus helveticus T 78. The temperature and time of the incubation of sausages, but not aw and pH, were found to have a distinct influence on the antagonistic interaction between the bacteria tested.

Use of hydrolysates from Atlantic cod (Gadus morhua L.) viscera as a complex nitrogen source for lactic acid bacteria.

PubMed

Aspmo, Stein Ivar; Horn, Svein Jarle; Eijsink, Vincent G H

2005-07-01

Hydrolysates of cod viscera were tested as an alternative to commonly used complex nitrogen sources (peptones and/or extracts) for the type strains of the lactic acid bacteria Lactococcus lactis, Lactobacillus acidophilus, Lactobacillus helveticus, Lactobacillus casei, Lactobacillus sakei and Pediococcus pentosaceus. Comparative studies with MRS-like media containing different nitrogen sources showed that all the fish hydrolysates performed equally well or better than commercial extracts/peptones for all selected lactic acid bacteria.

[The antagonistic properties of microaerophilic bacteria isolated from the human and mink digestive tracts].

PubMed

Sudenko, V I; Groma, L I; Podgorskiĭ, V S

1996-01-01

Study of antagonistic properties of microaerophilic bacteria isolated from human and mink gastroenteric tract have helped to establish differences in species composition, quantity and level of antagonistic activity of the studied microorganisms in respect to pathogenic microflora. It is shown that lactic acid bacteria identified as Lactobacillus fermentum and L. reuteri prevail among the strains isolated from the stomach and thin intestine of minks kept in the 30-km zone of Chernobyl NPP. Species composition of microaerophilic bacteria isolated from the digestive tract of the control minks is more variable. Antagonistically active bifidobacteria prevail in large intestine of experimental and control animals. Strains of lactic acid bacteria with the expressed antagonistic activity belonging to L. bavaricus, L. reuteri, L. coryniformis and L. maltaromicus have been found parallel with such known producers of antibiotic-like substances as L. fermentum. L. acidophilum. Streptococcus faecalis and bifidobacteria. L. maltaromicus most frequently occurred among antagonistically active strains revealed in feces of people which stayed in the zone of liquidation of the Chernobyl accident. Microaerophilic strains of bacteria (lactic acid, bifidobacteria and enterococci) manifest the expressed antagonistic activity connected with the capacity to not only acid formation but also to accumulation of antibiotic products of unknown nature. A strain of lactic acid bacteria L. fermentum 91 has been isolated from the contents of human gastroenteric tract. These bacteria are distinguished by most expressed and stable antagonism and characterized by the lack of pathogenicity in respect of albino mice that may be used to raise the microorganism resistance to gastric diseases.

Generalization of Extinguished Skin Conductance Responding in Human Fear Conditioning

ERIC Educational Resources Information Center

Vervliet, Bram; Vansteenwegen, Debora; Eelen, Paul

2004-01-01

In a human fear conditioning paradigm using the skin conductance response (SCR), participants were assigned to two groups. Following identical acquisition, group ABA (n = 16) was extinguished to a generalization stimulus (GS), whereas group AAB (n = 20) was extinguished to the conditioned stimulus (CS). At test, presenting the CS in group ABA…

An Activation/Inhibition Network Cell.

DTIC Science & Technology

1982-01-01

memory is a powerful concept, no one has found a way of doing activation and inhibition on it, so I’ll stick to the simple mapping. --------- AAB -W...Rumongus Scale Integration.. G-9- Vorking Paper 31 Referens. Fahiman, S.. NL: A s=u LI= rpnng A" using rial-world kowledge . MIT Pess, Cambridge, 1979

Mismatch Repair Balances Leading and Lagging Strand DNA Replication Fidelity

DTIC Science & Technology

2012-10-11

mismatched base stacks with a conserved phenylalanine in Msh6, and/or (iii) DNA flexibility, since MutSa-bound mismatched DNA is kinked, and a...AB, Watt DL , Watts BE, et al. (2010) Genome instability due to ribonucleotide incorporation into DNA. Nat Chem Biol 6: 774–781. 24. Poloumienko A

Parental Involvement and Academic Achievement of Middle School African American Students in Southeast Arkansas

ERIC Educational Resources Information Center

Allen, Christopher Steve

2017-01-01

The purpose of this quantitative, correlational study was to determine if a positive correlation existed between parental involvement measured by the Parental Involvement Survey and African American student Arkansas Augmented Benchmark Exam (AABE) mathematics and reading scores in two rural Southeast Arkansas middle schools. Epstein's theory of…

Synthesis, structural, optical and anti-rheumatic activity of metal complexes derived from (E)-2-amino-N-(1-(2-aminophenyl)ethylidene)benzohydrazide (2-AAB) with Ru(III), Pd(II) and Zr(IV)

NASA Astrophysics Data System (ADS)

Hosny, Nasser Mohammed; Sherif, Yousery E.

2015-02-01

Three new metal complexes derived from Pd(II), Ru(III) and Zr(IV) with (E)-2-amino-N-(1-(2-aminophenyl)ethylidene)benzohydrazide (2-AAB) have been synthesized. The isolated complexes were characterized by elemental analyses, FT-IR, UV-Vis, ES-MS, 1H NMR, XRD, thermal analyses (TGA and DTA) and conductance. The morphology and the particle size were determined by transmittance electron microscope (TEM). The results showed that, the ligand coordinates to Pd(II) in the enol form, while it coordinates to Ru(III) and Zr(IV) in the keto form. A square planar geometry is suggested for Pd(II) complex and octahedral geometries are suggested for Ru(III) and Zr(IV) complexes. The optical band gaps of the isolated complexes were measured and indicated the semi-conductivity nature of the complexes. The anti-inflammatory and analgesic activities of the ligand and its complexes showed that, Ru(III) complex has higher effect than the well known drug "meloxicam".

Consequences of bile salt biotransformations by intestinal bacteria

PubMed Central

Ridlon, Jason M.; Harris, Spencer C.; Bhowmik, Shiva; Kang, Dae-Joong; Hylemon, Phillip B.

2016-01-01

ABSTRACT Emerging evidence strongly suggest that the human “microbiome” plays an important role in both health and disease. Bile acids function both as detergents molecules promoting nutrient absorption in the intestines and as hormones regulating nutrient metabolism. Bile acids regulate metabolism via activation of specific nuclear receptors (NR) and G-protein coupled receptors (GPCRs). The circulating bile acid pool composition consists of primary bile acids produced from cholesterol in the liver, and secondary bile acids formed by specific gut bacteria. The various biotransformation of bile acids carried out by gut bacteria appear to regulate the structure of the gut microbiome and host physiology. Increased levels of secondary bile acids are associated with specific diseases of the GI system. Elucidating methods to control the gut microbiome and bile acid pool composition in humans may lead to a reduction in some of the major diseases of the liver, gall bladder and colon. PMID:26939849

Remediation of Acid Mine Drainage with Sulfate Reducing Bacteria

ERIC Educational Resources Information Center

Hauri, James F.; Schaider, Laurel A.

2009-01-01

Sulfate reducing bacteria have been shown to be effective at treating acid mine drainage through sulfide production and subsequent precipitation of metal sulfides. In this laboratory experiment for undergraduate environmental chemistry courses, students design and implement a set of bioreactors to remediate acid mine drainage and explain observed…

Reactivation of latent HIV-1 by a wide variety of butyric acid-producing bacteria.

PubMed

Imai, Kenichi; Yamada, Kiyoshi; Tamura, Muneaki; Ochiai, Kuniyasu; Okamoto, Takashi

2012-08-01

Latently infected cells harbor human immunodeficiency virus type 1 (HIV-1) proviral DNA copies integrated in heterochromatin, allowing persistence of transcriptionally silent proviruses. It is widely accepted that hypoacetylation of histone proteins by histone deacetylases (HDACs) is involved in maintaining the HIV-1 latency by repressing viral transcription. HIV-1 replication can be induced from latently infected cells by environmental factors, such as inflammation and co-infection with other microbes. It is known that a bacterial metabolite butyric acid inhibits catalytic action of HDAC and induces transcription of silenced genes including HIV-1 provirus. There are a number of such bacteria in gut, vaginal, and oral cavities that produce butyric acid during their anaerobic glycolysis. Since these organs are known to be the major site of HIV-1 transmission and its replication, we explored a possibility that explosive viral replication in these organs could be ascribable to butyric acid produced from anaerobic resident bacteria. In this study, we demonstrate that the culture supernatant of various bacteria producing butyric acid could greatly reactivate the latently-infected HIV-1. These bacteria include Fusobacterium nucleatum (commonly present in oral cavity, and gut), Clostridium cochlearium, Eubacterium multiforme (gut), and Anaerococcus tetradius (vagina). We also clarified that butyric acid in these culture supernatants could induce histone acetylation and HIV-1 replication by inhibiting HDAC. Our observations indicate that butyric acid-producing bacteria could be involved in AIDS progression by reactivating the latent HIV provirus and, subsequently, by eliminating such bacterial infection may contribute to the prevention of the AIDS development and transmission.

Production of pyroglutamic acid by thermophilic lactic acid bacteria in hard-cooked mini-cheeses.

PubMed

Mucchetti, G; Locci, F; Massara, P; Vitale, R; Neviani, E

2002-10-01

Pyroglutamic acid is present in high amounts (0.5g/ 100g) in many cheese varieties-and particularly in extensively ripened Italian cheeses such as Grana Padano and Parmigiano Reggiano. An in vivo model system for cooked mini-cheese production and ripening acceleration was set up to demonstrate the ability of thermophilic lactic acid bacteria, used as a starter, to produce pyroglutamic acid (pGlu). In mini-cheeses stored at 38 and 30 degrees C for up to 45 d, all starters tested produced different amounts of pGlu. In descending order of pGlu production, the bacteria analyzed were: Lactobacillus helveticus, Lactobacillus delbrueckii subsp. bulgaricus, Streptococcus thermophilus, and Lactobacillus delbrueckii subsp. lactis. Evidence for the presence of glutamine to pGlu cyclase activity in lactic acid bacteria was provided. Cell lysates obtained from cultures of L. helveticus, L. delbrueckii subsp. bulgaricus, L. delbrueckii subsp. lactis, and S. thermophilus showed the ability to cyclize glutamine to pGlu, resulting in processing yields from 1.4 to 30.3%, depending on the subspecies. Formation of pGlu from free glutamine appeared to be similar to that observed using a glutamine-glutamine dipeptide substrate. Under the experimental conditions applied, pGlu aminopeptidase activity was only detected in L. helveticus. Thus, pGlu formation in long-ripened cooked cheese may depend on the activity of thermophilic lactic acid bacteria.

Biodiversity of yeasts, lactic acid bacteria and acetic acid bacteria in the fermentation of "Shanxi aged vinegar", a traditional Chinese vinegar.

PubMed

Wu, Jia Jia; Ma, Ying Kun; Zhang, Fen Fen; Chen, Fu Sheng

2012-05-01

Shanxi aged vinegar is a famous traditional Chinese vinegar made from several kinds of cereal by spontaneous solid-state fermentation techniques. In order to get a comprehensive understanding of culturable microorganism's diversity present in its fermentation, the indigenous microorganisms including 47 yeast isolates, 28 lactic acid bacteria isolates and 58 acetic acid bacteria isolates were recovered in different fermenting time and characterized based on a combination of phenotypic and genotypic approaches including inter-delta/PCR, PCR-RFLP, ERIC/PCR analysis, as well as 16S rRNA and 26S rRNA partial gene sequencing. In the alcoholic fermentation, the dominant yeast species Saccharomyces (S.) cerevisiae (96%) exhibited low phenotypic and genotypic diversity among the isolates, while Lactobacillus (Lb.) fermentum together with Lb. plantarum, Lb. buchneri, Lb. casei, Pediococcus (P.) acidilactici, P. pentosaceus and Weissella confusa were predominated in the bacterial population at the same stage. Acetobacter (A.) pasteurianus showing great variety both in genotypic and phenotypic tests was the dominant species (76%) in the acetic acid fermentation stage, while the other acetic acid bacteria species including A. senegalensis, A. indonesiensis, A. malorum and A. orientalis, as well as Gluconobacter (G.) oxydans were detected at initial point of alcoholic and acetic acid fermentation stage respectively. Copyright © 2011 Elsevier Ltd. All rights reserved.

How endogenous plant pararetroviruses shed light on Musa evolution

PubMed Central

Duroy, Pierre-Olivier; Perrier, Xavier; Laboureau, Nathalie; Jacquemoud-Collet, Jean-Pierre; Iskra-Caruana, Marie-Line

2016-01-01

Background and Aims Banana genomes harbour numerous copies of viral sequences derived from banana streak viruses (BSVs) – dsDNA viruses belonging to the family Caulimoviridae. These viral integrants (eBSVs) are mostly defective, probably as a result of ‘pseudogenization’ driven by host genome evolution. However, some can give rise to infection by releasing a functional viral genome following abiotic stresses. These distinct infective eBSVs correspond to the three main widespread BSV species (BSOLV, BSGFV and BSIMV), fully described within the Musa balbisiana B genomes of the seedy diploid ‘Pisang Klutuk Wulung’ (PKW). Methods We characterize eBSV distribution among a Musa sampling including seedy BB diploids and interspecific hybrids with Musa acuminata exhibiting different levels of ploidy for the B genome (ABB, AAB, AB). We used representative samples of the two areas of sympatry between M. acuminata and M. balbisiana species representing the native area of the most widely cultivated AAB cultivars (in India and in East Asia, ranging from the Philippines to New Guinea). Seventy-seven accessions were characterized using eBSV-related PCR markers and Southern hybridization approaches. We coded both sets of results to create a common dissimilarity matrix with which to interpret eBSV distribution. Key Results We propose a Musa phylogeny driven by the M. balbisiana genome based on a dendrogram resulting from a joint neighbour-joining analysis of the three BSV species, showing for the first time lineages between BB and ABB/AAB hybrids. eBSVs appear to be relevant phylogenetic markers that can illustrate the M. balbisiana phylogeography story. Conclusion The theoretical implications of this study for further elucidation of the historical and geographical process of Musa domestication are numerous. Discovery of banana plants with B genome non-infective for eBSV opens the way to the introduction of new genitors in programmes of genetic banana improvement. PMID:26971286

How endogenous plant pararetroviruses shed light on Musa evolution.

PubMed

Duroy, Pierre-Olivier; Perrier, Xavier; Laboureau, Nathalie; Jacquemoud-Collet, Jean-Pierre; Iskra-Caruana, Marie-Line

2016-04-01

Banana genomes harbour numerous copies of viral sequences derived from banana streak viruses (BSVs) - dsDNA viruses belonging to the family Caulimoviridae.These viral integrants (eBSVs) are mostly defective, probably as a result of 'pseudogenization' driven by host genome evolution. However, some can give rise to infection by releasing a functional viral genome following abiotic stresses. These distinct infective eBSVs correspond to the three main widespread BSV species (BSOLV, BSGFV and BSIMV), fully described within the Musa balbisiana B genomes of the seedy diploid 'Pisang Klutuk Wulung' (PKW). We characterize eBSV distribution among a Musa sampling including seedy BB diploids and interspecific hybrids with Musa acuminate exhibiting different levels of ploidy for the B genome (ABB, AAB, AB). We used representative samples of the two areas of sympatry between M. acuminate and M. balbisiana species representing the native area of the most widely cultivated AAB cultivars (in India and in East Asia, ranging from the Philippines to New Guinea). Seventy-seven accessions were characterized using eBSV-related PCR markers and Southern hybridization approaches. We coded both sets of results to create a common dissimilarity matrix with which to interpret eBSV distribution. We propose a Musa phylogeny driven by the M. balbisiana genome based on a dendrogram resulting from a joint neighbour-joining analysis of the three BSV species, showing for the first time lineages between BB and ABB/AAB hybrids. eBSVs appear to be relevant phylogenetic markers that can illustrate theM. balbisiana phylogeography story. The theoretical implications of this study for further elucidation of the historical and geographical process of Musa domestication are numerous. Discovery of banana plants with B genome non-infective for eBSV opens the way to the introduction of new genitors in programmes of genetic banana improvement. © The Author 2016. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Traditional Banana Diversity in Oceania: An Endangered Heritage

PubMed Central

Kagy, Valérie; Wong, Maurice; Vandenbroucke, Henri; Jenny, Christophe; Dubois, Cécile; Ollivier, Anthony; Cardi, Céline; Mournet, Pierre; Tuia, Valérie; Roux, Nicolas; Doležel, Jaroslav; Perrier, Xavier

2016-01-01

This study aims to understand the genetic diversity of traditional Oceanian starchy bananas in order to propose an efficient conservation strategy for these endangered varieties. SSR and DArT molecular markers are used to characterize a large sample of Pacific accessions, from New Guinea to Tahiti and Hawaii. All Pacific starchy bananas are shown of New Guinea origin, by interspecific hybridization between Musa acuminata (AA genome), more precisely its local subspecies M. acuminata ssp. banksii, and M. balbisiana (BB genome) generating triploid AAB Pacific starchy bananas. These AAB genotypes do not form a subgroup sensu stricto and genetic markers differentiate two subgroups across the three morphotypes usually identified: Iholena versus Popoulu and Maoli. The Popoulu/Maoli accessions, even if morphologically diverse throughout the Pacific, cluster in the same genetic subgroup. However, the subgroup is not strictly monophyletic and several close, but different genotypes are linked to the dominant genotype. One of the related genotypes is specific to New Caledonia (NC), with morphotypes close to Maoli, but with some primitive characters. It is concluded that the diffusion of Pacific starchy AAB bananas results from a series of introductions of triploids originating in New Guinea area from several sexual recombination events implying different genotypes of M. acuminata ssp. banksii. This scheme of multiple waves from the New Guinea zone is consistent with the archaeological data for peopling of the Pacific. The present geographic distribution suggests that a greater diversity must have existed in the past. Its erosion finds parallels with the erosion of cultural traditions, inexorably declining in most of the Polynesian or Melanesian Islands. Symmetrically, diversity hot spots appear linked to the local persistence of traditions: Maoli in New Caledonian Kanak traditions or Iholena in a few Polynesian islands. These results will contribute to optimizing the conservation strategy for the ex-situ Pacific Banana Collection supported collectively by the Pacific countries. PMID:26982801

Three-year follow-up of syndromal antisocial behavior in adults: results from the Wave 2 National Epidemiologic Survey on Alcohol and Related Conditions.

PubMed

Goldstein, Risë B; Grant, Bridget F

2009-09-01

To present nationally representative findings on total antisocial personality disorder (ASPD) symptoms, major violations of others' rights (MVOR), and violent symptoms over a 3-year follow-up in Wave 2 of the National Epidemiologic Survey on Alcohol and Related Conditions among adults diagnosed at Wave 1 with ASPD versus syndromal adult antisocial behavior without conduct disorder before age 15 years (AABS, not a codable DSM-IV disorder). Face-to-face interviews were conducted with 34,653 respondents aged 18 years and older. Antisocial syndromes and comorbid lifetime substance use, mood, and 6 additional personality disorders were diagnosed at Wave 1 using the Alcohol Use Disorder and Associated Disabilities Interview Schedule-DSM-IV Version (AUDADIS-IV). The Wave 2 AUDADIS-IV assessed antisocial symptoms over follow-up, lifetime attention-deficit/hyperactivity disorder (ADHD) and posttraumatic stress disorder, and borderline, narcissistic, and schizotypal personality disorders. Wave 1 was conducted in 2001-2002 and Wave 2 in 2004-2005 by the National Institute on Alcohol Abuse and Alcoholism. In unadjusted analyses, respondents with ASPD reported significantly more total, MVOR, and violent symptoms over follow-up than did respondents with AABS. Adjustment for baseline sociodemographics and psychiatric comorbidity attenuated these associations; after further adjustment for parallel antisocial symptom counts from age 15 years to Wave 1, associations with antisocial syndromes disappeared. Independent Wave 1 predictors of persistent antisociality over follow-up included male sex, not being married or cohabiting, low income, high school or less education, lifetime drug use disorders, additional personality disorders, and ADHD. The distinction between ASPD and AABS holds limited value in predicting short-term course of antisocial symptomatology among adults. However, the prediction of persistent antisociality by psychiatric comorbidity argues for comprehensive diagnostic assessments, treatment of all identified disorders, and investigation of whether treatment of comorbidity might hasten remission of antisociality. Copyright 2009 Physicians Postgraduate Press, Inc.

Altered Antibody Profiles against Common Infectious Agents in Chronic Disease

PubMed Central

Burbelo, Peter D.; Ching, Kathryn H.; Morse, Caryn G.; Alevizos, Ilias; Bayat, Ahmad; Cohen, Jeffrey I.; Ali, Mir A.; Kapoor, Amit; Browne, Sarah K.; Holland, Steven M.; Kovacs, Joseph A.; Iadarola, Michael J.

2013-01-01

Despite the important diagnostic value of evaluating antibody responses to individual human pathogens, antibody profiles against multiple infectious agents have not been used to explore health and disease mainly for technical reasons.  We hypothesized that the interplay between infection and chronic disease might be revealed by profiling antibodies against multiple agents. Here, the levels of antibodies against a panel of 13 common infectious agents were evaluated with the quantitative Luciferase Immunoprecipitation Systems (LIPS) in patients from three disease cohorts including those with pathogenic anti-interferon-γ autoantibodies (IFN-γ AAB), HIV and Sjögren’s syndrome (SjS) to determine if their antibody profiles differed from control subjects.  The IFN-γ AAB patients compared to controls demonstrated statistically higher levels of antibodies against VZV (p=0.0003), EBV (p=0.002), CMV (p=0.003), and C. albicans (p=0.03), but lower antibody levels against poliovirus (p=0.04). Comparison of HIV patients with blood donor controls revealed that the patients had higher levels of antibodies against CMV (p=0.0008), HSV-2 (p=0.0008), EBV (p=0.001), and C. albicans (p=0.01), but showed decreased levels of antibodies against coxsackievirus B4 (p=0.0008), poliovirus (p=0.0005),   and HHV-6B (p=0.002). Lastly, SjS patients had higher levels of anti-EBV antibodies (p=0.03), but lower antibody levels against several enteroviruses including a newly identified picornavirus, HCoSV-A (p=0.004), coxsackievirus B4 (p=0.04), and poliovirus (p=0.02). For the IFN-γ AAB and HIV cohorts, principal component analysis revealed unique antibody clusters that showed the potential to discriminate patients from controls.  The results suggest that antibody profiles against these and likely other common infectious agents may yield insight into the interplay between exposure to infectious agents, dysbiosis, adaptive immunity and disease activity. PMID:24312567

An Indirect Immunofluorescence Method Facilitates Detection of Thrombospondin Type 1 Domain–Containing 7A–Specific Antibodies in Membranous Nephropathy

PubMed Central

Hoxha, Elion; Beck, Laurence H.; Wiech, Thorsten; Tomas, Nicola M.; Probst, Christian; Mindorf, Swantje; Meyer-Schwesinger, Catherine; Zahner, Gunther; Stahl, Phillip R.; Schöpper, Ruth; Panzer, Ulf; Harendza, Sigrid; Helmchen, Udo; Salant, David J.

2017-01-01

Thrombospondin type 1 domain–containing 7A (THSD7A) is a target antigen identified in adult membranous nephropathy (MN) along with the major antigen phospholipase A2 receptor 1 (PLA2R1). The prevalence of THSD7A-Ab–positive patients is unknown, and it is unclear whether the clinical presentation differs between patients positive for PLA2R1-Ab or THSD7A-Ab. We screened serum samples of 1276 patients with MN from three different cohorts for the presence of THSD7A-Ab by Western blot analysis and a newly developed indirect immunofluorescence test (IFT). Compared with Western blot analysis, the IFT had a 92% sensitivity and a 100% specificity. The prevalence of THSD7A-associated MN in a prospective cohort of 345 patients with MN was 2.6%, and most were women. In this cohort, the percentage of patients with THSD7A-associated MN and malignant disease significantly exceeded that of patients with PLA2R1-associated MN and malignant disease. In all cohorts, we identified 40 patients with THSD7A-associated MN, eight of whom developed a malignancy within a median time of 3 months from diagnosis of MN. In one patient with THSD7A-associated MN and metastases of an endometrial carcinoma, immunohistochemistry showed THSD7A expression on the metastatic cells and within follicular dendritic cells of the metastasis–infiltrated lymph node. We conclude that the IFT allows sensitive and specific measurement of circulating THSD7A-Ab in patients with MN. Patients with THSD7A-associated MN differ in their clinical characteristics from patients with PLA2R1-associated MN, and more intensive screening for the presence of malignancies may be warranted in those with THSD7A-associated MN. PMID:27436855

Traditional Banana Diversity in Oceania: An Endangered Heritage.

PubMed

Kagy, Valérie; Wong, Maurice; Vandenbroucke, Henri; Jenny, Christophe; Dubois, Cécile; Ollivier, Anthony; Cardi, Céline; Mournet, Pierre; Tuia, Valérie; Roux, Nicolas; Doležel, Jaroslav; Perrier, Xavier

2016-01-01

This study aims to understand the genetic diversity of traditional Oceanian starchy bananas in order to propose an efficient conservation strategy for these endangered varieties. SSR and DArT molecular markers are used to characterize a large sample of Pacific accessions, from New Guinea to Tahiti and Hawaii. All Pacific starchy bananas are shown of New Guinea origin, by interspecific hybridization between Musa acuminata (AA genome), more precisely its local subspecies M. acuminata ssp. banksii, and M. balbisiana (BB genome) generating triploid AAB Pacific starchy bananas. These AAB genotypes do not form a subgroup sensu stricto and genetic markers differentiate two subgroups across the three morphotypes usually identified: Iholena versus Popoulu and Maoli. The Popoulu/Maoli accessions, even if morphologically diverse throughout the Pacific, cluster in the same genetic subgroup. However, the subgroup is not strictly monophyletic and several close, but different genotypes are linked to the dominant genotype. One of the related genotypes is specific to New Caledonia (NC), with morphotypes close to Maoli, but with some primitive characters. It is concluded that the diffusion of Pacific starchy AAB bananas results from a series of introductions of triploids originating in New Guinea area from several sexual recombination events implying different genotypes of M. acuminata ssp. banksii. This scheme of multiple waves from the New Guinea zone is consistent with the archaeological data for peopling of the Pacific. The present geographic distribution suggests that a greater diversity must have existed in the past. Its erosion finds parallels with the erosion of cultural traditions, inexorably declining in most of the Polynesian or Melanesian Islands. Symmetrically, diversity hot spots appear linked to the local persistence of traditions: Maoli in New Caledonian Kanak traditions or Iholena in a few Polynesian islands. These results will contribute to optimizing the conservation strategy for the ex-situ Pacific Banana Collection supported collectively by the Pacific countries.

Citric acid metabolism in hetero- and homofermentative lactic acid bacteria.

PubMed Central

Drinan, D F; Robin, S; Cogan, T M

1976-01-01

The effect of citrate on production of diacetyl and acetoin by four strains each of heterofermentative and homofermentative lactic acid bacteria capable of utilizing citrate was studied. Acetoin was quantitatively the more important compound. The heterofermentative bacteria produced no acetoin or diacetyl in the absence of citrate, and two strains produced traces of acetoin in its presence. Citrate stimulated the growth rate of the heterofermentative lactobacilli. Acidification of all heterofermentative cultures with citric acid resulted in acetoin production. Destruction of accumulated acetoin appeared to coincide with the disappearance of citrate. All homofermentative bacteria produced more acetoin and diacetyl in the presence of citrate than in its absence. Citrate utilization was begun immediately by the streptococci but was delayed until at least the middle of the exponential phase in the case of the lactobacilli. PMID:5054

Phenotypic and genotypic characterization of lactic acid bacteria from traditional cheese in Khorramabad city of Iran with probiotic potential.

PubMed

Ghahremani, Enayat; Mardani, Mahnaz; Rezapour, Sadegh

2015-03-01

Lactic acid bacteria (LAB) with proteolitic activity are used as aromatic and antibacterial substances, cholesterol reduces, bile salt hydrolyses, and probiotic. The aims of this project were to isolate and identify natural LAB flora involved in traditional fermentation in cheeses of Khoramabad city and also to survey their probiotic potential. In order to achieve this goal, LAB were isolated and characterized using phenotypic and genotypic methods (PCR-sequencing); in the next stage, they were analyzed lowering cholesterol medium, hydrolysis of the bile, resistance to bile-resistant PH acidic stomach. At the end of the study, 88 cocci and 3 bacill were found: 58 Enterococcus faecium, 16 Enterococcus hirae, 5 Lactococcus lactis, 3 Lactobacillus plantarum, and 9 undetermined. The probiotic results of the bacteria had effects on the reduction of cholesterol, resistance to stomach acid, had relative antibacterial effects, and some strains had effects on hydrolyzing the bile. For further identification, the PCR method and the application of 16s-DNA-ITS genes and its sequencing were found useful. This study showed that lactic acid bacteria in the traditional cheese of the Khorramabad city have relative probiotic effect and that these lactic acid bacteria in fermented milk are suitable.

Is Bacterial Fatty Acid Synthesis a Valid Target for Antibacterial Drug Discovery?

PubMed Central

Parsons, Joshua B.; Rock, Charles O.

2011-01-01

The emergence of resistance against most current drugs emphasizes the need to develop new approaches to control bacterial pathogens, particularly Staphylococcus aureus. Bacterial fatty acid synthesis is one such target that is being actively pursued by several research groups to develop anti-Staphylococcal agents. Recently, the wisdom of this approach has been challenged based on the ability of a Gram-positive bacterium to incorporate extracellular fatty acids and thus circumvent the inhibition of de novo fatty acid synthesis. The generality of this conclusion has been challenged, and there is enough diversity in the enzymes and regulation of fatty acid synthesis in bacteria to conclude that there isn’t a single organism that can be considered typical and representative of bacteria as a whole. We are left without a clear resolution to this ongoing debate and await new basic research to define the pathways for fatty acid uptake and that determine the biochemical and genetic mechanisms for the regulation of fatty acid synthesis in Gram-positive bacteria. These crucial experiments will determine whether diversity in the control of this important pathway accounts for the apparently different responses of Gram-positive bacteria to the inhibition of de novo fatty acid synthesis in presence of extracellular fatty acid supplements. PMID:21862391

Bacterial Long-Chain Polyunsaturated Fatty Acids: Their Biosynthetic Genes, Functions, and Practical Use

PubMed Central

Yoshida, Kiyohito; Hashimoto, Mikako; Hori, Ryuji; Adachi, Takumi; Okuyama, Hidetoshi; Orikasa, Yoshitake; Nagamine, Tadashi; Shimizu, Satoru; Ueno, Akio; Morita, Naoki

2016-01-01

The nutritional and pharmaceutical values of long-chain polyunsaturated fatty acids (LC-PUFAs) such as arachidonic, eicosapentaenoic and docosahexaenoic acids have been well recognized. These LC-PUFAs are physiologically important compounds in bacteria and eukaryotes. Although little is known about the biosynthetic mechanisms and functions of LC-PUFAs in bacteria compared to those in higher organisms, a combination of genetic, bioinformatic, and molecular biological approaches to LC-PUFA-producing bacteria and some eukaryotes have revealed the notably diverse organization of the pfa genes encoding a polyunsaturated fatty acid synthase complex (PUFA synthase), the LC-PUFA biosynthetic processes, and tertiary structures of the domains of this enzyme. In bacteria, LC-PUFAs appear to take part in specific functions facilitating individual membrane proteins rather than in the adjustment of the physical fluidity of the whole cell membrane. Very long chain polyunsaturated hydrocarbons (LC-HCs) such as hentriacontanonaene are considered to be closely related to LC-PUFAs in their biosynthesis and function. The possible role of LC-HCs in strictly anaerobic bacteria under aerobic and anaerobic environments and the evolutionary relationships of anaerobic and aerobic bacteria carrying pfa-like genes are also discussed. PMID:27187420

Systems solutions by lactic acid bacteria: from paradigms to practice

PubMed Central

2011-01-01

Lactic acid bacteria are among the powerhouses of the food industry, colonize the surfaces of plants and animals, and contribute to our health and well-being. The genomic characterization of LAB has rocketed and presently over 100 complete or nearly complete genomes are available, many of which serve as scientific paradigms. Moreover, functional and comparative metagenomic studies are taking off and provide a wealth of insight in the activity of lactic acid bacteria used in a variety of applications, ranging from starters in complex fermentations to their marketing as probiotics. In this new era of high throughput analysis, biology has become big science. Hence, there is a need to systematically store the generated information, apply this in an intelligent way, and provide modalities for constructing self-learning systems that can be used for future improvements. This review addresses these systems solutions with a state of the art overview of the present paradigms that relate to the use of lactic acid bacteria in industrial applications. Moreover, an outlook is presented of the future developments that include the transition into practice as well as the use of lactic acid bacteria in synthetic biology and other next generation applications. PMID:21995776

Oxalic acid biosynthesis is encoded by an operon in Burkholderia glumae

USDA-ARS?s Scientific Manuscript database

Although the biosynthesis of oxalic acid is known to occur in a number of bacteria, the mechanism(s) regulating its production remains largely unknown. To date, there is no report on the identification of an oxalic acid biosynthetic pathway gene from bacteria. In an attempt to identify such a gene...

Precision genome engineering in lactic acid bacteria

PubMed Central

2014-01-01

Innovative new genome engineering technologies for manipulating chromosomes have appeared in the last decade. One of these technologies, recombination mediated genetic engineering (recombineering) allows for precision DNA engineering of chromosomes and plasmids in Escherichia coli. Single-stranded DNA recombineering (SSDR) allows for the generation of subtle mutations without the need for selection and without leaving behind any foreign DNA. In this review we discuss the application of SSDR technology in lactic acid bacteria, with an emphasis on key factors that were critical to move this technology from E. coli into Lactobacillus reuteri and Lactococcus lactis. We also provide a blueprint for how to proceed if one is attempting to establish SSDR technology in a lactic acid bacterium. The emergence of CRISPR-Cas technology in genome engineering and its potential application to enhancing SSDR in lactic acid bacteria is discussed. The ability to perform precision genome engineering in medically and industrially important lactic acid bacteria will allow for the genetic improvement of strains without compromising safety. PMID:25185700

Acetic acid production from food wastes using yeast and acetic acid bacteria micro-aerobic fermentation.

PubMed

Li, Yang; He, Dongwei; Niu, Dongjie; Zhao, Youcai

2015-05-01

In this study, yeast and acetic acid bacteria strains were adopted to enhance the ethanol-type fermentation resulting to a volatile fatty acids yield of 30.22 g/L, and improve acetic acid production to 25.88 g/L, with food wastes as substrate. In contrast, only 12.81 g/L acetic acid can be obtained in the absence of strains. The parameters such as pH, oxidation reduction potential and volatile fatty acids were tested and the microbial diversity of different strains and activity of hydrolytic ferment were investigated to reveal the mechanism. The optimum pH and oxidation reduction potential for the acetic acid production were determined to be at 3.0-3.5 and -500 mV, respectively. Yeast can convert organic matters into ethanol, which is used by acetic acid bacteria to convert the organic wastes into acetic acid. The acetic acid thus obtained from food wastes micro-aerobic fermentation liquid could be extracted by distillation to get high-pure acetic acid.

Uptake of free amino acids by bacteria-free larvae of the sand dollar Dendraster excentricus.

PubMed

Davis, J P; Stephens, G C

1984-10-01

Larvae of Dendraster excentricus were produced by collecting gametes and carrying out fertilization under aseptic conditions. Since gametes are free of bacteria in the gonad, bacteria-free (axenic) suspensions of larvae result. Net rates of entry of 14 amino acids and the rate of production of ammonia were simultaneously determined by high-performance liquid chromatography. The net rates of uptake of neutral amino acids were an order of magnitude greater than rates for basic and acidic amino acids. Influx of 14C-labeled leucine, arginine, and glutamate accurately reflects the net entry rate of these substrates. Uptake of amino acids by axenic suspensions of larvae was compared with uptake by suspensions prepared without aseptic precautions. There was no significant difference in net uptake of the 14 amino acids or in the pattern of oxidation and assimilation of [14C]leucine during short-term experiments of 4-h duration or less.

Effect of high hydrostatic pressure on the polyphenols and antioxidant activity of plantain pulp (Musa paradisiaca AAB).

PubMed

Jiménez-Martínez, Miriam C; Montalvo-González, Efigenia; Sáyago-Ayerdi, Sonia G; Mercado-Mercado, Gilberto; Ramírez-de León, José A; Paz-Gamboa, Ernestina; Vivar-Vera, Maria A

2017-06-01

The impact of high-pressure processing (HPP) on the polyphenol (PP) content and antioxidant activity (AOX) of plantain pulp was evaluated. Pressures of 400, 500 and 600 MPa were applied to plantain pulp for 90 and 180 s at room temperature (25 °C). Polyphenoloxidase activity, extractable (EPP) and non-extractable PP (NEPP) contents, flavonoid content and AOX (FRAP, ABTS •+ ) were evaluated. In addition, PP identification was performed using high-performance liquid chromatography. Polyphenoloxidase activity was inhibited after HPP under all of the conditions studied. Increases of 110.80% and 137.40% in EPP content under conditions of 500 MPa/180 s and 600 MPa/90 s were observed with a simultaneous improvement in the AOX with increments of up to 128.71%. The treatment under conditions of 500 MPa/90 s had the highest total PP content, including the highest content of flavonoids (0.22 g ellagic acid equivalents kg -1  dry weight) and the proportion of NEPP that contained hydrolysable PPs (91.12 g gallic acid equivalents kg -1  dry weight with high AOX. The identified PPs included catechin, quercetin, gallic and hydroxybenzoic acids. HPP performed at a room temperature can be used for improving the total content of PP compounds in plantain pulp under specific pressure and time conditions. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Plasmids from Food Lactic Acid Bacteria: Diversity, Similarity, and New Developments

PubMed Central

Cui, Yanhua; Hu, Tong; Qu, Xiaojun; Zhang, Lanwei; Ding, Zhongqing; Dong, Aijun

2015-01-01

Plasmids are widely distributed in different sources of lactic acid bacteria (LAB) as self-replicating extrachromosomal genetic materials, and have received considerable attention due to their close relationship with many important functions as well as some industrially relevant characteristics of the LAB species. They are interesting with regard to the development of food-grade cloning vectors. This review summarizes new developments in the area of lactic acid bacteria plasmids and aims to provide up to date information that can be used in related future research. PMID:26068451

Microbiological diversity and prevalence of spoilage and pathogenic bacteria in commercial fermented alcoholic beverages (beer, fruit wine, refined rice wine, and yakju).

PubMed

Jeon, Se Hui; Kim, Nam Hee; Shim, Moon Bo; Jeon, Young Wook; Ahn, Ji Hye; Lee, Soon Ho; Hwang, In Gyun; Rhee, Min Suk

2015-04-01

The present study examined 469 commercially available fermented alcoholic beverages (FABs), including beer (draft, microbrewed, and pasteurized), fruit wine (grape and others), refined rice wine, and yakju (raw and pasteurized). Samples were screened for Escherichia coli and eight foodborne pathogens (Bacillus cereus, Campylobacter jejuni, Clostridium perfringens, Escherichia coli O157:H7, Listeria monocytogenes, Salmonella spp., Staphylococcus aureus, and Yersinia enterocolitica), and the aerobic plate count, lactic acid bacteria, acetic acid bacteria, fungi, and total coliforms were also enumerated. Microbrewed beer contained the highest number of microorganisms (average aerobic plate count, 3.5; lactic acid bacteria, 2.1; acetic acid bacteria, 2.0; and fungi, 3.6 log CFU/ml), followed by draft beer and yakju (P < 0.05), whereas the other FABs contained , 25 CFU/25 ml microorganisms. Unexpectedly, neither microbial diversity nor microbial count correlated with the alcohol content (4.7 to 14.1%) or pH (3.4 to 4.2) of the product. Despite the harsh conditions, coliforms (detected in 23.8% of microbrewed beer samples) and B. cereus (detected in all FABs) were present in some products. B. cereus was detected most frequently in microbrewed beer (54.8% of samples) and nonpasteurized yakju (50.0%), followed by pasteurized yakju (28.8%), refined rice wine (25.0%), other fruit wines (12.3%), grape wine (8.6%), draft beer (5.6%), and pasteurized beer (2.2%) (P < 0.05). The finding that spore-forming B. cereus and coliform bacteria can survive the harsh conditions present in alcoholic beverages should be taken into account (alongside traditional quality indicators such as the presence of lactic acid-producing bacteria, acetic acid-producing bacteria, or both) when developing manufacturing systems and methods to prolong the shelf life of high-quality FAB products. New strategic quality management plans for various FABs are needed.

Antibacterial effects of roselle calyx extracts and protocatechuic acid in ground beef and apple juice.

PubMed

Chao, Che-Yi; Yin, Mei-Chin

2009-03-01

The antibacterial effects of roselle calyx aqueous and ethanol extracts and protocatechuic acid against food spoilage bacteria Salmonella typhimurium DT104, Escherichia coli O157:H7, Listeria monocytogenes, Staphylococcus aureus, and Bacillus cereus were examined. Minimal inhibitory concentrations of roselle calyx aqueous and ethanol extracts and protocatechuic acid against these bacteria were in the range of 112-144, 72-96, and 24-44 microg/mL, respectively. Protocatechuic acid content in roselle calyx aqueous and ethanol extracts was 2.8 +/- 0.7 and 11.9 +/- 1.2 mg/g, respectively. Antibacterial activity of roselle calyx ethanol extract and protocatechuic acid was not affected by heat treatments from 25 degrees to 75 degrees C and 25 degrees to 100 degrees C, respectively. After 3 days storage at 25 degrees C, the addition of roselle calyx extracts and protocatechuic acid exhibited dose-dependent inhibitory effects against test bacteria in ground beef and apple juice, in which the roselle calyx ethanol extract showed greater antibacterial effects than the aqueous extract. These data suggest that roselle calyx ethanol extract and protocatechuic acid might be potent agents as food additives to prevent contamination from these bacteria.

Identification by using MALDI-TOF mass spectrometry of lactic acid bacteria isolated from non-commercial yogurts in southern Anatolia, Turkey.

PubMed

Karaduman, Ayse; Ozaslan, Mehmet Ozaslan; Kilic, Ibrahim H; Bayil-Oguzkan, Sibel; Kurt, Bekir S; Erdogan, Nese

2017-03-01

Yogurt is a dairy product obtained by bacterial fermentation of milk. Commercial yogurts are produced using standard starters while, in the production of non-commercial yogurt, the microbiota is quite different since yogurts are used as starter for years. To determine the final characteristics of the fermented product it is necessary to know the biochemical properties of the starter cultures, such as acidity, aroma and flavor. This can only be achieved by identifying and characterizing the bacteria in starter cultures. In our study, 208 non-commercial yogurt samples were collected from 9 different locations in Anatolia, southern Turkey. Their pH and lactic acid bacteria profiles were analyzed. Isolated bacteria were identified by MALDI-TOF MS (matrix-assisted laser sesorption-ionization time-of-flight, mass spectrometry), which is a fast and reliable method for identification of bacterial isolates compared to classical laboratory methods. In this study, 41% of the isolates were identified by using this method, which is 99.9% and 34.0% confidence. The isolates contained two genera (Enterococcus and Lactobacillus) and four species. Afterwards, the four lactic acid bacteria were characterized physiologically and biochemically and we found that they differed from lactic acid bacteria used in commercial yogurt production. [Int Microbiol 20(1): 25-30 (2017)]. Copyright© by the Spanish Society for Microbiology and Institute for Catalan Studies.

Analysis of 16S rRNA gene lactic acid bacteria (LAB) isolate from Markisa fruit (Passiflora sp.) as a producer of protease enzyme and probiotics

NASA Astrophysics Data System (ADS)

Hidayat, Habibi

2017-03-01

16S rRNA gene analysis of bacteria lactic acid (LAB) isolate from Markisa Kuning Fruit (Passiflora edulis var. flavicarpa) as a producer of protease enzyme and probiotics has been done. The aim of the study is to determine the protease enzyme activity and 16S rRNA gene amplification using PCR. The calculation procedure was done to M4 isolate bacteria lactic acid (LAB) Isolate which has been resistant to acids with pH 2.0 in the manner of screening protease enzyme activity test result 6.5 to clear zone is 13 mm againts colony diametre is 2 mm. The results of study enzyme activity used spectrophotometer UV-Vis obtainable the regression equation Y=0.02983+0.001312X, with levels of protein M4 isolate is 0.6594 mg/mL and enzyme activity of obtainable is 0.8626 unit/ml while the spesific enzyme activity produced is 1.308 unit/mg. Then, 16S rRNA gene amplificatiom and DNA sequencing has been done. The results of study showed that the bacteria species contained from M4 bacteria lactic acid (LAB) isolate is Weisella cibiria strain II-I-59. Weisella cibiria strain II-I-59 is one of bacteria could be utilized in the digestive tract.

Digestion of rice straw and oil palm fronds by microflora from rumen and termite bacteria, in vitro.

PubMed

Ramin, M; Alimon, A R; Panandam, J M; Sijam, K; Javanmard, A; Abdullah, N

2008-02-15

The digestion and Volatile Fatty Acid (VFA) production from rice straw and oil palm fronds by cellulolytic bacteria isolated from the termite Coptotermes curvignathus were investigated. The bacteria were Acinetobacter strain Raminalimon, Enterobacter aerogenes strain Razmin C, Enterobacter cloacae strain Razmin B, Bacillus cereus strain Razmin A and Chryseobacterium kwangyangense strain Cb. Acinetobacter strain Raminalimon is an aerobic bacterium, while the other species are facultative anaerobes. There were significant differences (p<0.05) among the bacteria for Dry Matter (DM) lost and acetic acid production from rice straw and Acinetobacter strain Raminalimon showed the highest activity. The facultative bacteria C. kwangyangense strain Cb (cfu mL(-1) 231 x 10(-6), OD: 0.5), E. cloacae (cfu mL(-1) 68 x 10(-7), OD: 0.5) and E. aerogenes (cfu mL(-1) 33 x 10(-7), OD: 0.5) were used for digestion study with the rumen fluid microflora. The in vitro gas production technique was applied for the comparative study and the parameters measured were pH, gas (volume), dry matter lost, acetic acid, propionic acid and butyric acid concentrations. pH was not significantly (p<0.05) different among the five treatments. The bacterium C. kwangyangense strain Cb showed the highest activity (p<0.05) for DM lost, acetic acid, propionic acid and butyric acid production from rice straw when compared to the other bacterial activities. There was no significance (p<0.05) difference between the three bacteria for the dry matter lost of oil palm fronds but the production of Volatile Fatty Acids (VFA) was significantly (p<0.05) high in the treatment which was inoculated with C. kwangyangense strain Cb. The Gen Bank NCBI/EMBL accession numbers for the bacterial strains are EU332791, EU305608, EU305609, EU294508 and EU169201.

Antibacterial activity of sphingoid bases and fatty acids against Gram-positive and Gram-negative bacteria.

PubMed

Fischer, Carol L; Drake, David R; Dawson, Deborah V; Blanchette, Derek R; Brogden, Kim A; Wertz, Philip W

2012-03-01

There is growing evidence that the role of lipids in innate immunity is more important than previously realized. How lipids interact with bacteria to achieve a level of protection, however, is still poorly understood. To begin to address the mechanisms of antibacterial activity, we determined MICs and minimum bactericidal concentrations (MBCs) of lipids common to the skin and oral cavity--the sphingoid bases D-sphingosine, phytosphingosine, and dihydrosphingosine and the fatty acids sapienic acid and lauric acid--against four Gram-negative bacteria and seven Gram-positive bacteria. Exact Kruskal-Wallis tests of these values showed differences among lipid treatments (P < 0.0001) for each bacterial species except Serratia marcescens and Pseudomonas aeruginosa. D-sphingosine (MBC range, 0.3 to 19.6 μg/ml), dihydrosphingosine (MBC range, 0.6 to 39.1 μg/ml), and phytosphingosine (MBC range, 3.3 to 62.5 μg/ml) were active against all bacteria except S. marcescens and P. aeruginosa (MBC > 500 μg/ml). Sapienic acid (MBC range, 31.3 to 375.0 μg/ml) was active against Streptococcus sanguinis, Streptococcus mitis, and Fusobacterium nucleatum but not active against Escherichia coli, Staphylococcus aureus, S. marcescens, P. aeruginosa, Corynebacterium bovis, Corynebacterium striatum, and Corynebacterium jeikeium (MBC > 500 μg/ml). Lauric acid (MBC range, 6.8 to 375.0 μg/ml) was active against all bacteria except E. coli, S. marcescens, and P. aeruginosa (MBC > 500 μg/ml). Complete killing was achieved as early as 0.5 h for some lipids but took as long as 24 h for others. Hence, sphingoid bases and fatty acids have different antibacterial activities and may have potential for prophylactic or therapeutic intervention in infection.

Lactic Acid Bacteria Exopolysaccharides in Foods and Beverages: Isolation, Properties, Characterization, and Health Benefits.

PubMed

Lynch, Kieran M; Zannini, Emanuele; Coffey, Aidan; Arendt, Elke K

2018-03-25

Exopolysaccharides produced by lactic acid bacteria are a diverse group of polysaccharides produced by many species. They vary widely in their molecular, compositional, and structural characteristics, including mechanisms of synthesis. The physiochemical properties of these polymers mean that they can be exploited for the sensorial and textural enhancement of a variety of food and beverage products. Traditionally, lactic acid bacteria exopolysaccharides have an important role in fermented dairy products and more recently are being applied for the improvement of bakery products. The health benefits that are continually being associated with these polysaccharides enable the development of dual function, added-value, and clean-label products. To fully exploit and understand the functionality of these exopolysaccharides, their isolation, purification, and thorough characterization are of great importance. This review considers each of the above factors and presents the current knowledge on the importance of lactic acid bacteria exopolysaccharides in the food and beverage industry.

Long-Term Benefits of Prompts to Use Safety Belts among Drivers Exiting Senior Communities

ERIC Educational Resources Information Center

Cox, Cory D.; Cox, Brian S.; Cox, Daniel J.

2005-01-01

Senior drivers are vulnerable to automobile crashes and subsequent injury and death. Safety belts reduce health risks associated with auto crashes. Therefore, it is important to encourage senior drivers to wear safety belts while driving. Using a repeated baseline design (AAB), we previously reported that motivating signs boosted safety belt usage…

Three-Valued Logics and Conditional Event Algebras

DTIC Science & Technology

1990-12-05

order) over R Bruno & Gilio (10), among others. In all of the represented by the relation a.b iff a=a-b iff b=bva; above, only DeFinetti and Schay...ce’s (101 G. Bruno and A. Gilio , "Confronto fra eventi with interpretations for their outcomes through €. condizionati di probabiliti nulli nell’ infer

Effects of poly-γ-glutamic acid biopreparation (PGAB) on nitrogen conservation in the coastal saline soil

NASA Astrophysics Data System (ADS)

Chen, Lihua; Xu, Xianghong; Zhang, Huan; Han, Rui; Cheng, Yao; Tan, Xueyi; Chen, Xuanyu

2017-04-01

Water leaching is the major method to decrease soil salinity of the coastal saline soil. Conservation of soil nutrition in the soil ameliorating process is helpful to maintain soil fertility and prevent environment pollution. In the experiment, glutamic acid and poly-γ-glutamic acid (PGA) producing bacteria were isolated for manufacturing the PGA biopreparation (PGAB), and the effect of PGAB on the soil nitrogen (N) conservation was assayed. The glutamic acid and PGA producing bacteria were identified as Brevibacterium flavum and Bacillus amyloliquefaciens. After soil leached with water for 90 days, compared to control treatment, salt concentration of 0-30cm soil with PGAB treatment was lowered by 39.93%, however the total N loss was decreased by 65.37%. Compared to control, the microbial biomass N increased by 1.19 times at 0-30 cm soil with PGAB treatment. The populations of soil total bacteria, fungi, actinomyces, nitrogen fixing bacteria, ammonifying bacteria, nitrifying bacteria and denitrifying bacteria and biomass of soil algae were significantly increased in PGAB treatment, while anaerobic bacteria decreased (P<0.05). In addition, the percentage of soil aggregates with diameter > 0.25 mm and 0.02 mm < diameter <0.25 mm were increased by 2.93 times and 26.79% respectively in PGAB treatment. The soil erosion-resistance coefficient of PGAB treatment increased by 50%. All these suggested that the PGAB conserved the soil nitrogen effectively in the process of soil water leaching and improved the coastal saline soil quality.

Phenolic Composition and Evaluation of the Antimicrobial Activity of Free and Bound Phenolic Fractions from a Peruvian Purple Corn (Zea mays L.) Accession.

PubMed

Gálvez Ranilla, Lena; Christopher, Ashish; Sarkar, Dipayan; Shetty, Kalidas; Chirinos, Rosana; Campos, David

2017-12-01

Beneficial effects on overall gut health by phenolic bioactives-rich foods are potentially due to their modulation of probiotic gut bacteria and antimicrobial activity against pathogenic bacteria. Based on this rationale, the effect of the free and bound phenolic fractions from a Peruvian purple corn accession AREQ-084 on probiotic lactic acid bacteria such as Lactobacillus helveticus and Bifidobacterium longum and the gastric cancer-related pathogen Helicobacter pylori was evaluated. The free and bound phenolic composition was also determined by ultra-performance liquid chromatography. Anthocyanins were the major phenolic compounds (310.04 mg cyanidin-3-glucoside equivalents/100 g dry weight, DW) in the free phenolic fraction along with hydroxycinnamic acids such as p-coumaric acid derivatives, followed by caffeic and ferulic acid derivatives. The bound phenolic form had only hydroxycinnamic acids such as ferulic acid, p-coumaric acid, and a ferulic acid derivative with ferulic acid being the major phenolic compound (156.30 mg/100 g DW). These phenolic compounds were compatible with beneficial probiotic lactic acid bacteria such as L. helveticus and B. longum as these bacteria were not inhibited by the free and bound phenolic fractions at 10 to 50 mg/mL and 10 mg/mL of sample doses, respectively. However, the pathogenic H. pylori was also not inhibited by both purple corn phenolic forms at same above sample doses. This study provides the preliminary base for the characterization of phenolic compounds of Peruvian purple corn biodiversity and its potential health benefits relevant to improving human gut health. This study provides insights that Peruvian purple corn accession AREQ-084 can be targeted as a potential source of health-relevant phenolic compounds such as anthocyanins along with hydroxycinnamic acids linked to its dietary fiber fraction. Additionally, these phenolic fractions did not affect the gut health associated beneficial bacteria nor the pathogenic H. pylori. Purple corn can be targeted for design of probiotic functional foods integrated with their anthocyanin linked-coloring properties. © 2017 Institute of Food Technologists®.

Plasmonic-based colorimetric and spectroscopic discrimination of acetic and butyric acids produced by different types of Escherichia coli through the different assembly structures formation of gold nanoparticles.

PubMed

La, Ju A; Lim, Sora; Park, Hyo Jeong; Heo, Min-Ji; Sang, Byoung-In; Oh, Min-Kyu; Cho, Eun Chul

2016-08-24

We present a plasmonic-based strategy for the colourimetric and spectroscopic differentiation of various organic acids produced by bacteria. The strategy is based on our discovery that particular concentrations of dl-lactic, acetic, and butyric acids induce different assembly structures, colours, and optical spectra of gold nanoparticles. We selected wild-type (K-12 W3110) and genetically-engineered (JHL61) Escherichia coli (E. coli) that are known to primarily produce acetic and butyric acid, respectively. Different assembly structures and optical properties of gold nanoparticles were observed when different organic acids, obtained after the removal of acid-producing bacteria, were mixed with gold nanoparticles. Moreover, at moderate cell concentrations of K-12 W3110 E. coli, which produce sufficient amounts of acetic acid to induce the assembly of gold nanoparticles, a direct estimate of the number of bacteria was possible based on time-course colour change observations of gold nanoparticle aqueous suspensions. The plasmonic-based colourimetric and spectroscopic methods described here may enable onsite testing for the identification of organic acids produced by bacteria and the estimation of bacterial numbers, which have applications in health and environmental sciences. Copyright © 2016 Elsevier B.V. All rights reserved.

Comparison of nitroethane, 2-nitro-1-propanol, lauric acid, Lauricidin and the Hawaiian marine algae, Chaetoceros, for potential broad-spectrum control of anaerobically grown lactic acid bacteria

USDA-ARS?s Scientific Manuscript database

The gastrointestinal tract of bovines often contains bacteria that contribute to disorders of the rumen and may also contain foodborne or opportunistic human pathogens as well as bacteria capable of causing mastitis in cows. Thus, there is a need to develop broad-spectrum therapies that are effecti...

Intrinsic and extrinsic carbohydrates in the vagina: A short review on vaginal glycogen.

PubMed

Tester, Richard; Al-Ghazzewi, Farage H

2018-06-01

The reasons for (i) the presence and (ii) mechanisms of utilisation of glycogen by the lactic acid bacteria in the human vaginal tract are not well understood. It is probable that the vaginal epithelia produce both glycogen and α-amylase where the enzyme depolymerises the polysaccharide within the vagina itself. Only these depolymerised residues are then utilised for growth by the lactic acid bacteria. The lactic acid bacteria cannot metabolise the glycogen directly due to their incapacity to produce the α-amylase enzyme. These bacteria may, however, metabolise exogenous carbohydrates (such as prebiotics) selectively for growth effectively. These carbohydrate utilisation issues within the vagina are considered in this short review. Copyright © 2018 Elsevier B.V. All rights reserved.

The role of microbial amino acid metabolism in host metabolism.

PubMed

Neis, Evelien P J G; Dejong, Cornelis H C; Rensen, Sander S

2015-04-16

Disruptions in gut microbiota composition and function are increasingly implicated in the pathogenesis of obesity, insulin resistance, and type 2 diabetes mellitus. The functional output of the gut microbiota, including short-chain fatty acids and amino acids, are thought to be important modulators underlying the development of these disorders. Gut bacteria can alter the bioavailability of amino acids by utilization of several amino acids originating from both alimentary and endogenous proteins. In turn, gut bacteria also provide amino acids to the host. This could have significant implications in the context of insulin resistance and type 2 diabetes mellitus, conditions associated with elevated systemic concentrations of certain amino acids, in particular the aromatic and branched-chain amino acids. Moreover, several amino acids released by gut bacteria can serve as precursors for the synthesis of short-chain fatty acids, which also play a role in the development of obesity. In this review, we aim to compile the available evidence on the contribution of microbial amino acids to host amino acid homeostasis, and to assess the role of the gut microbiota as a determinant of amino acid and short-chain fatty acid perturbations in human obesity and type 2 diabetes mellitus.

Inferring Phytoplankton, Terrestrial Plant and Bacteria Bulk δ¹³C Values from Compound Specific Analyses of Lipids and Fatty Acids

PubMed Central

Taipale, Sami J.; Peltomaa, Elina; Hiltunen, Minna; Jones, Roger I.; Hahn, Martin W.; Biasi, Christina; Brett, Michael T.

2015-01-01

Stable isotope mixing models in aquatic ecology require δ13C values for food web end members such as phytoplankton and bacteria, however it is rarely possible to measure these directly. Hence there is a critical need for improved methods for estimating the δ13C ratios of phytoplankton, bacteria and terrestrial detritus from within mixed seston. We determined the δ13C values of lipids, phospholipids and biomarker fatty acids and used these to calculate isotopic differences compared to the whole-cell δ13C values for eight phytoplankton classes, five bacterial taxa, and three types of terrestrial organic matter (two trees and one grass). The lipid content was higher amongst the phytoplankton (9.5±4.0%) than bacteria (7.3±0.8%) or terrestrial matter (3.9±1.7%). Our measurements revealed that the δ13C values of lipids followed phylogenetic classification among phytoplankton (78.2% of variance was explained by class), bacteria and terrestrial matter, and there was a strong correlation between the δ13C values of total lipids, phospholipids and individual fatty acids. Amongst the phytoplankton, the isotopic difference between biomarker fatty acids and bulk biomass averaged -10.7±1.1‰ for Chlorophyceae and Cyanophyceae, and -6.1±1.7‰ for Cryptophyceae, Chrysophyceae and Diatomophyceae. For heterotrophic bacteria and for type I and type II methane-oxidizing bacteria our results showed a -1.3±1.3‰, -8.0±4.4‰, and -3.4±1.4‰ δ13C difference, respectively, between biomarker fatty acids and bulk biomass. For terrestrial matter the isotopic difference averaged -6.6±1.2‰. Based on these results, the δ13C values of total lipids and biomarker fatty acids can be used to determine the δ13C values of bulk phytoplankton, bacteria or terrestrial matter with ± 1.4‰ uncertainty (i.e., the pooled SD of the isotopic difference for all samples). We conclude that when compound-specific stable isotope analyses become more widely available, the determination of δ13C values for selected biomarker fatty acids coupled with established isotopic differences, offers a promising way to determine taxa-specific bulk δ13C values for the phytoplankton, bacteria, and terrestrial detritus embedded within mixed seston. PMID:26208114

Lactic Acid Bateria - Friend or Foe? Lactic Acid Bacteria in the Production of Polysaccharides and Fuel Ethanol

USDA-ARS?s Scientific Manuscript database

Lactic acid bacteria (LAB) have been widely used in the production of fermented foods and as probiotics. Alternan is a glucan with a distinctive backbone structure of alternating alpha-(1,6) and alpha-(1,3) linkages produced by the LAB Leuconostoc mesenteroides. In recent years, improved strains f...

Combined physico-chemical treatments based on enterocin AS-48 for inactivation of Gram-negative bacteria in soybean sprouts.

PubMed

Cobo Molinos, Antonio; Abriouel, Hikmate; López, Rosario Lucas; Valdivia, Eva; Omar, Nabil Ben; Gálvez, Antonio

2008-08-01

Enterocin AS-48 was tested for decontamination of soybean sprouts against Gram-negative bacteria. Although treatment with bacteriocin alone had no effect on Salmonella enterica, a synergistic antimicrobial effect was detected at pH 9.0 and in combination with moderate heat treatment. Greatest inactivation was achieved for sprouts heated for 5 min at 65 degrees C in an alkaline (pH 9.0) enterocin AS-48 solution of 25 microg/ml. Bactericidal activity against S. enterica increased greatly when enterocin AS-48 was used in washing solutions in combination with several chemical compounds: EDTA, lactic acid, peracetic acid, polyphosphoric acid, sodium hypochlorite, hexadecylpyridinium chloride, propyl-p-hydroxybenzoate, and hydrocinnamic acid. The combined treatment of enterocin AS-48 and polyphosphoric acid was tested against several other Gram-negative bacteria inoculated on sprouts. The bacteria tested showed great differences in sensitivity to polyphosphoric acid, but synergism with enterocin AS-48 was confirmed in all cases. Combinations of enterocin AS-48 (25 microg/ml) and polyphosphoric acid in a concentration range of 0.1 to 2.0% significantly reduced or inhibited growth of the populations of S. enterica, Escherichia coli O157:H7, Shigella spp., Enterobacter aerogenes, Yersinia enterocolitica, Aeromonas hydrophila and Pseudomonas fluorescens in sprout samples stored at 6 degrees C and 15 degrees C. The combined treatment could therefore be applied to reduce the risks of Gram-negative pathogenic as well as spoilage bacteria on sprouts.

Antioxidant Potential and Antibacterial Efficiency of Caffeic Acid-Functionalized ZnO Nanoparticles

PubMed Central

Choi, Kyong-Hoon; Nam, Ki Chang; Lee, Sang-Yoon; Cho, Guangsup; Jung, Jin-Seung; Kim, Ho-Joong; Park, Bong Joo

2017-01-01

We report a novel zinc oxide (ZnO) nanoparticle with antioxidant properties, prepared by immobilizing the antioxidant 3-(3,4-dihydroxyphenyl)-2-propenoic acid (caffeic acid, CA) on the surfaces of micro-dielectric barrier discharge (DBD) plasma-treated ZnO nanoparticles. The microstructure and physical properties of ZnO@CA nanoparticles were characterized by field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), infrared spectroscopy, and steady state spectroscopic methods. The antioxidant activity of ZnO@CA nanoparticles was evaluated using an ABTS (3-ethyl-benzothiazoline-6-sulfonic acid) radical cation decolorization assay. ZnO@CA nanoparticles exhibited robust antioxidant activity. Moreover, ZnO@CA nanoparticles showed strong antibacterial activity against Gram-positive bacteria (Staphylococcus aureus) including resistant bacteria such as methicillin-resistant S. aureus and against Gram-negative bacteria (Escherichia coli). Although Gram-negative bacteria appeared to be more resistant to ZnO@CA nanoparticles than Gram-positive bacteria, the antibacterial activity of ZnO@CA nanoparticles was dependent on particle concentration. The antioxidant and antibacterial activity of ZnO@CA may be useful for various biomedical and nanoindustrial applications. PMID:28621707

A urolith of biogenic dolomite - another clue in the dolomite mystery

NASA Astrophysics Data System (ADS)

Mansfield, Charles F.

1980-06-01

A male Dalmatian, Canis familiaris, produced uroliths of almost pure dolomite, 3-8 mm across, in his urinary bladder in less than 8 months at 38°C and about 1 atm. The X-ray diffractogram identified the predominant mineral as dolomite, and the sharp (01.5) peak showed it is ordered dolomite, not the disordered form, protodolomite. Geochemically and biologically plausible causes include (1) renal, respiratory, or metabolic alkalosis, (2) infection by urease-producing (urea-splitting) fungi or bacteria and (3) infection by uric acid-fermenting bacteria. Hematological, bacteriological, urological and geochemical considerations most strongly implicate infection by either anaerobic, urease-producing bacteria or anaerobic, uric acid-fermenting bacteria. The physical and chemical conditions of this urinary system more closely approximate modern and inferred ancient carbonate depositional settings than most previous laboratory experiments, especially in terms of temperature, pressure, total salinity and, possibly, biota. The presence of urease-producing and/or uric acid-fermenting bacteria in urea- and/or acid-containing sediment, such as fecal pellets and algal mats, could promote formation of authigenic dolomite or other carbonates.

Total lactic acid bacteria, antioxidant activity, and acceptance of synbiotic yoghurt with red ginger extract (Zingiberofficinale var. rubrum)

NASA Astrophysics Data System (ADS)

Larasati, B. A.; Panunggal, B.; Afifah, D. N.; Anjani, G.; Rustanti, N.

2018-02-01

Antioxidant related to oxidative stress can caused the metabolic disorders. A functional food that high in antioxidant can be use as the alternative prevention. The addition of red ginger extract in yoghurt could form a functional food, that high in antioxidant, synbiotic and fiber. The influence of red ginger extract on yoghurt synbiotic against lactic acid bacteria, antioxidant activity and acceptance were analyzed. This was an experimental research with one factor complete randomized design, specifically the addition of red ginger extract 0%; 0,1%; 0,3% and 0,5% into synbiotic yoghurt. Total plate count method used to analyze the lactic acid bacteria, 1-1-diphenyl-2-picrylhydrazyl (DPPH) method for antioxidant activity, and acceptance analyzed with hedonic test. The higher the dose of extract added to synbiotic yoghurt, the antioxidant activity got significantly increased (ρ=0,0001), while the lactic acid bacteria got insignificantly decreased (ρ=0,085). The addition of 0,5% red ginger extract obtained the antioxidant activity of 71% and 4,86 × 1013 CFU/ml on lactic acid bacteria, which the requirement for probiotic on National Standard of Indonesia is >107 CFU/ml. The addition of extract had a significant effect on acceptance (ρ=0,0001) in flavor, color, and texture, but not aroma (ρ=0,266). The optimal product in this research was the yoghurt synbiotic with addition of 0,1% red ginger extract. To summarize, the addition of red ginger extract in synbiotic yoghurt had significant effect on antioxidant activity, flavor, color, and texture, but no significant effect on lactic acid bacteria and aroma.

Enzymatic polymerization of natural anacardic acid and antibiofouling effects of polyanacardic acid coatings.

PubMed

Chelikani, Rahul; Kim, Yong Hwan; Yoon, Do-Young; Kim, Dong-Shik

2009-05-01

Anacardic acid, separated from cashew nut shell liquid, is well known for its strong antibiotic and antioxidant activities. Recent findings indicate that phenolic compounds from plant sources have an effect on Gram-negative bacteria biofilm formation. In this work, a polyphenolic coating was prepared from anacardic acid using enzymatic synthesis and tested for its effects on biofilm formation of both Gram-negative and Gram-positive bacteria. Natural anacardic acid was enzymatically polymerized using soybean peroxidase. Hydrogen peroxide and phenothiazine-10-propionic acid were used as an oxidizing agent and redox mediator, respectively. Nuclear magnetic resonance and Fourier transform infrared (FTIR) analyses showed the formation of oxyphenylene and phenylene units through the phenol rings. No linkage through the alkyl chain was observed, which proved a high chemo-selectivity of the enzyme. Aqueous solvents turned out to play an important role in the polymer production yield and molecular weight. With 2-propanol, the highest production yield (61%) of polymer (molecular weight = 3,900) was observed, and with methanol, higher-molecular-weight polymers (5,000) were produced with lower production yields (43%). The resulting polyanacardic acid was cross-linked on a solid surface to form a permanent natural polymer coating. The FTIR analysis indicates that the cross-linking between the polymers took place through the unsaturated alkyl side chains. The polyanacardic acid coating was then tested for its antibiofouling effect against Gram-negative and Gram-positive bacteria and compared with the antibiofouling effects of polycardanol coatings reported in the literature. The polyanacardic acid coating showed more reduction in biofilm formation on its surface than polycardanol coatings in the case of Gram-positive bacteria, while in the case of Gram-negative bacteria, it showed a similar reduction in biofilm formation as polycardanol.

Simplification of a complex microbial antilisterial consortium to evaluate the contribution of its flora in uncooked pressed cheese.

PubMed

Callon, Cécile; Saubusse, Marjorie; Didienne, Robert; Buchin, Solange; Montel, Marie-Christine

2011-02-28

A complex microbial consortium derived from raw milk and composed of populations classified in 4 groups (lactic acid bacteria (A), Gram positive catalase positive bacteria (B), Gram negative bacteria (C) and yeasts (D)) can contribute to the inhibition of Listeria monocytogenes in the core of an uncooked pressed cheese. To identify what groups may be involved in the inhibition, the consortium was simplified by successively omitting one group at a time. Pasteurized milk was inoculated with these more or less complex consortia and their effects on L. monocytogenes count, pH, acids and volatile compounds in the core of uncooked pressed cheese were evaluated. The growth of L. monocytogenes was the highest in cheeses prepared with pasteurized milk and only St. thermophilus. Inhibition in other cheeses was expressed by comparison with growth in these ones. All the consortia containing both lactic acid bacteria (group A) and Gram positive catalase positive bacteria (group B)--ABCD, ABD, ABC, AB--were more inhibitory than those containing lactic acid bacteria on its own (A) or associated only with yeasts (AD) or/and Gram negative (ADC). Consortia without lactic acid bacteria were weakly inhibitory or had no effect. Gram positive catalase positive bacteria alone were not inhibitory although most of the species became established in the cheeses. The Lactobacillus population (Lb. casei, Lb. plantarum, Lb. curvatus and Lb. farciminis) was predominant in cheeses (9 log CFU/g) with a higher count than Leuconostoc (7 log CFU/g) and Enterococcus (7 log CFU/g). Lactobacillus counts were negatively correlated with those of L. monocytogenes (r=-0.84 at 18 days) and with the level of D-lactic acid. There was no correlation between L. monocytogenes and Leuconostoc or Enterococcus counts. Complex consortium ABCD and AB not only had a stronger inhibitory power in cheeses than consortium AD, they were also associated with the highest levels of L-lactic and acetic acids. All cheeses inoculated with lactic acid bacteria differed from those without by higher levels of ethyl formiate, pentane and alcohols (2-butanol, 2-pentanol), and lower levels of ketones (2-hexanone, 2,3-butanedione) and aldehydes (2-methyl-butanal). Levels of 2-methyl-butanal, 2-butanol and 2-pentanol were higher in ABCD and AB cheeses than in AD cheeses. Beside their contribution to the inhibition, their effect on cheese flavour must be evaluated. Published by Elsevier B.V.

Linking autotrophic activity in environmental samples with specific bacterial taxa by detection of 13C-labelled fatty acids.

PubMed

Knief, Claudia; Altendorf, Karlheinz; Lipski, André

2003-11-01

A method for the detection of physiologically active autotrophic bacteria in complex microbial communities was developed based on labelling with the stable isotope 13C. Labelling of autotrophic nitrifying, sulphur-oxidizing and iron-oxidizing populations was performed in situ by incubation with NaH[13C]O3. Incorporated label into fatty acid methyl esters (FAMEs) was detected and quantified using gas chromatography-mass spectrometry in single ion monitoring mode. Before the analyses of different environmental samples, the protocol was evaluated in pure culture experiments. In different environmental samples a selective labelling of fatty acids demonstrated which microbial taxa were responsible for the respective chemolithoautotrophic activity. The most strongly labelled fatty acids of a sample from a sulphide treating biofilter from an animal rendering plant were cis-7-hexadecenoic acid (16:1 cis7) and 11-methyl hexadecanoic acid (16:0 11methyl), which are as-yet not known for any sulphide-oxidizing autotroph. The fatty acid labelling pattern of an experimental biotrickling filter sample supplied with dimethyl disulphide clearly indicated the presence and activity of sulphide-oxidizing bacteria of the genus Thiobacillus. For a third environmental sample from an acid mining lake sediment, the assignment of autotrophic activity to bacteria of the genus Leptospirillum but not to Acidithiobacillus could be made by this method, as the fatty acid patterns of these bacteria show clear differences.

Taxonomic composition and physiological and biochemical properties of bacteria in the digestive tracts of earthworms

NASA Astrophysics Data System (ADS)

Byzov, B. A.; Tikhonov, V. V.; Nechitailo, T. Yu.; Demin, V. V.; Zvyagintsev, D. G.

2015-03-01

Several hundred bacterial strains belonging to different taxa were isolated and identified from the digestive tracts of soil and compost earthworms. Some physiological and biochemical properties of the bacteria were characterized. The majority of intestinal bacteria in the earthworms were found to be facultative anaerobes. The intestinal isolates as compared to the soil ones had elevated activity of proteases and dehydrogenases. In addition, bacteria associated with earthworms' intestines are capable of growth on humic acids as a sole carbon source. Humic acid stimulated the growth of the intestinal bacteria to a greater extent than those of the soil ones. In the digestive tracts, polyphenol oxidase activity was found. Along with the data on the taxonomic separation of the intestinal bacteria, the features described testified to the presence of a group of bacteria in the earthworms intestines that is functionally characteristic and is different from the soil bacteria.

[Biodiversity of phosphate-dissolving and plant growth--promoting endophytic bacteria of two crops].

PubMed

Huang, Jing; Sheng, Xiafang; He, Linyan

2010-06-01

We isolated and characterized phosphate-dissolving endophytic bacteria from two commonly cultivated crops. Phosphate-dissolving endophytic bacteria were isolated by plating and screening from interior tissues of rape and maize plants on NBRIP medium with tricalcium phosphate as sole phosphate source. Bacteria were characterized regarding characteristics that may be relevant for a beneficial plant-microbe interaction-indoleacetic acid, siderophore and 1-aminocyclopropane-1-carboxylic acid deaminase production,and further classified by restriction analysis of 16S rDNA. Eleven typical strains were identified by 16S rDNA sequence analysis. Thirty-two phosphate-dissolving endophytic bacteria were isolated from maize and rape plants and classified by restriction analysis of 16S rDNA in 8 different taxonomic groups at the similarity level of 76%. All the isolates could release phosphate from tricalcium phosphate and decrease the pH of the medium. The maximum phosphate content (537.6 mg/L) in the solution was obtained with strain M1L5. Thirteen isolates isolated from rape produced indoleacetic acid and siderophore, 68.4% and 63.2% of the strains isolated from maize produced indoleacetic acid and siderophore,respectively. 63.2% of the strains isolated from maize were able to grow on 1-aminocyclopropane-1-carboxylic acid as the sole nitrogen source. The eleven strains belonged to five different genera including Pantoea, Pseudomonas, Burkholderia, Acinetobacter and Ralstonia. Phosphate-dissolving endophytic bacteria isolated from rape and maize plants have abundant characteristics relative to promoting plant growth and genetic diversity.

Effect of pH alkaline salts of fatty acids on the inhibition of bacteria associated with poultry processing

USDA-ARS?s Scientific Manuscript database

The agar diffusion assay was used to examine the effect of pH on the ability of alkaline salts of three fatty acids (FA) to inhibit growth of bacteria associated with poultry processing. FA solutions were prepared by dissolving 0.5 M concentrations of caprylic, capric, or lauric acid in separate ali...

Microbiological and chemical characteristics of Brazilian kefir during fermentation and storage processes.

PubMed

Leite, A M O; Leite, D C A; Del Aguila, E M; Alvares, T S; Peixoto, R S; Miguel, M A L; Silva, J T; Paschoalin, V M F

2013-07-01

The microbial community composition and chemical characteristics of a Brazilian milk kefir sample produced during its manufacturing and refrigerated storage were investigated by culture-dependent and -independent methods and HPLC. Lactococcus lactis ssp. cremoris and ssp. lactis, Leuconostoc mesenteroides, Acetobacter lovaniensis, and Saccharomyces cerevisiae were isolated, whereas the detected bands on denaturing gel gradient electrophoresis corresponded to Lactobacillus kefiranofaciens, Lactobacillus kefiri, Lactobacillus parakefiri, and S. cerevisiae. After fermentation, lactic acid bacteria were present at levels of 10 log units, whereas acetic acid bacteria and yeast were present at levels of 7.8 and 6 log units, respectively. The lactic acid bacteria and yeast counts remained constant, whereas acetic acid bacteria counts decreased to 7.2 log units during storage. From fermentation to final storage, the pH, lactose content and citric acid of the kefir beverage decreased, followed by an increase in the concentrations of glucose, galactose, ethanol, and lactic, acetic, butyric, and propionic acids. These microbiological and chemical characteristics contribute to the unique taste and aroma of kefir. This research may serve as a basis for the future industrial production of this beverage in Brazil. Copyright © 2013 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Give us the tools and we will do the job: symbiotic bacteria affect olive fly fitness in a diet-dependent fashion.

PubMed

Ben-Yosef, Michael; Aharon, Yael; Jurkevitch, Edouard; Yuval, Boaz

2010-05-22

Olive flies (Bactrocera oleae) are intimately associated with bacteria throughout their life cycle, and both larvae and adults are morphologically adapted for housing bacteria in the digestive tract. We tested the hypothesis that these bacteria contribute to the adult fly's fitness in a diet-dependent fashion. We predicted that when dietary protein is superabundant, bacterial contribution will be minimal. Conversely, in the absence of protein, or when only non-essential amino acids are present (as in the fly's natural diet), we predicted that bacterial contribution to fitness will be significant. Accordingly, we manipulated diet and the presence of bacteria in female olive flies, and monitored fecundity--an indirect measure of fitness. Bacteria did not affect fecundity when females were fed a nutritionally poor diet of sucrose, or a protein-rich, nutritionally complete diet. However, when females were fed a diet containing non-essential amino acids as the sole source of amino nitrogen, egg production was significantly enhanced in the presence of bacteria. These results suggest that bacteria were able to compensate for the skewed amino acid composition of the diet and may be indispensable for wild adult olive flies that subsist mainly on nitrogen-poor resources such as honeydew.

Quantification of Triacylglycerol Molecular Species in Edible Fats and Oils by Gas Chromatography-Flame Ionization Detector Using Correction Factors.

PubMed

Yoshinaga, Kazuaki; Obi, Junji; Nagai, Toshiharu; Iioka, Hiroyuki; Yoshida, Akihiko; Beppu, Fumiaki; Gotoh, Naohiro

2017-03-01

In the present study, the resolution parameters and correction factors (CFs) of triacylglycerol (TAG) standards were estimated by gas chromatography-flame ionization detector (GC-FID) to achieve the precise quantification of the TAG composition in edible fats and oils. Forty seven TAG standards comprising capric acid, lauric acid, myristic acid, pentadecanoic acid, palmitic acid, palmitoleic acid, stearic acid, oleic acid, linoleic acid, and/or linolenic acid were analyzed, and the CFs of these TAGs were obtained against tripentadecanoyl glycerol as the internal standard. The capillary column was Ultra ALLOY + -65 (30 m × 0.25 mm i.d., 0.10 μm thickness) and the column temperature was programmed to rise from 250°C to 360°C at 4°C/min and then hold for 25 min. The limit of detection (LOD) and limit of quantification (LOQ) values of the TAG standards were > 0.10 mg and > 0.32 mg per 100 mg fat and oil, respectively, except for LnLnLn, and the LOD and LOQ values of LnLnLn were 0.55 mg and 1.84 mg per 100 mg fat and oil, respectively. The CFs of TAG standards decreased with increasing total acyl carbon number and degree of desaturation of TAG molecules. Also, there were no remarkable differences in the CFs between TAG positional isomers such as 1-palmitoyl-2-oleoyl-3-stearoyl-rac-glycerol, 1-stearoyl-2-palmitoyl-3-oleoyl-rac-glycerol, and 1-palmitoyl-2-stearoyl-3-oleoyl-rac-glycerol, which cannot be separated by GC-FID. Furthermore, this method was able to predict the CFs of heterogeneous (AAB- and ABC-type) TAGs from the CFs of homogenous (AAA-, BBB-, and CCC-type) TAGs. In addition, the TAG composition in cocoa butter, palm oil, and canola oil was determined using CFs, and the results were found to be in good agreement with those reported in the literature. Therefore, the GC-FID method using CFs can be successfully used for the quantification of TAG molecular species in natural fats and oils.

Sialidases from gut bacteria: a mini-review.

PubMed

Juge, Nathalie; Tailford, Louise; Owen, C David

2016-02-01

Sialidases are a large group of enzymes, the majority of which catalyses the cleavage of terminal sialic acids from complex carbohydrates on glycoproteins or glycolipids. In the gastrointestinal (GI) tract, sialic acid residues are mostly found in terminal location of mucins via α2-3/6 glycosidic linkages. Many enteric commensal and pathogenic bacteria can utilize sialic acids as a nutrient source, but not all express the sialidases that are required to release free sialic acid. Sialidases encoded by gut bacteria vary in terms of their substrate specificity and their enzymatic reaction. Most are hydrolytic sialidases, which release free sialic acid from sialylated substrates. However, there are also examples with transglycosylation activities. Recently, a third class of sialidases, intramolecular trans-sialidase (IT-sialidase), has been discovered in gut microbiota, releasing (2,7-anhydro-Neu5Ac) 2,7-anydro-N-acetylneuraminic acid instead of sialic acid. Reaction specificity varies, with hydrolytic sialidases demonstrating broad activity against α2,3-, α2,6- and α2,8-linked substrates, whereas IT-sialidases tend to be specific for α2,3-linked substrates. In this mini-review, we summarize the current knowledge on the structural and biochemical properties of sialidases involved in the interaction between gut bacteria and epithelial surfaces. © 2016 Authors.

Defined bacterial populations in the rumens of gnotobiotic lambs.

PubMed

Lysons, R J; Alexander, T J; Wellstead, P D; Hobson, P N; Mann, S O; Stewart, C S

1976-06-01

Five gnotobiotic lambs were fed on sterile diets until they were killed at 13 to 21 weeks of age. They were dosed orally with different combinations of 11 species of rumen bacteria. The biochemical reactions of each of the bacteria inoculated had been determined in pure culture in vitro, and they were chosen to perform the main reactions known to be associated with digestion in the normal mature rumen. Two of the bacteria could not be reisolated, but the remainder had established readily in the rumen, forming stable, mixed, defined populations. The total numbers of bacteria in the rumen, and the viable counts of most of the individual species were comparable to those of normal sheep. The concentration of volatile fatty acids was lower, however, and in four of the lambs there was a higher proportion of butyric acid and a lower proportion of propionic acid than in normal sheep. Cellulolytic, ureolytic, and methanogenic activities appeared to be taking place and lactate-utilizing bacteria appeared to reverse the accumulation of lactate which resulted from the activity of lactate-producing bacteria. Some of the bacteria also established at high levels in the caecum.

Biotechnological production of polyamines by bacteria: recent achievements and future perspectives.

PubMed

Schneider, Jens; Wendisch, Volker F

2011-07-01

In Bacteria, the pathways of polyamine biosynthesis start with the amino acids L-lysine, L-ornithine, L-arginine, or L-aspartic acid. Some of these polyamines are of special interest due to their use in the production of engineering plastics (e.g., polyamides) or as curing agents in polymer applications. At present, the polyamines for industrial use are mainly synthesized on chemical routes. However, since a commercial market for polyamines as well as an industry for the fermentative production of amino acid exist, and since bacterial strains overproducing the polyamine precursors L-lysine, L-ornithine, and L-arginine are known, it was envisioned to engineer these amino acid-producing strains for polyamine production. Only recently, researchers have investigated the potential of amino acid-producing strains of Corynebacterium glutamicum and Escherichia coli for polyamine production. This mini-review illustrates the current knowledge of polyamine metabolism in Bacteria, including anabolism, catabolism, uptake, and excretion. The recent advances in engineering the industrial model bacteria C. glutamicum and E. coli for efficient production of the most promising polyamines, putrescine (1,4-diaminobutane), and cadaverine (1,5-diaminopentane), are discussed in more detail.

MONITORING OF SYNERGISTIC ENHANCEMENT OF CAFFEIC ACID ON ESCHERICHIA COLI K-12 RECA::GFP STRAIN TREATED WITH DACARBAZINE.

PubMed

Matejczyk, Marzena; Swislocka, Renata; Kalinowska, Monika; Swidersk, Grzegorz; Lewandowsk, Wlodzimierz; Jablonska-Trypuo, Agata

2017-05-01

Caffeic acid and its derivatives because of its biological activities, including antioxidants, antithrombosis, antihypertensive, antifibrosis, antiviral, and anti-tumor properties are good candidates as adjuvants in anticancer therapy. The aim of this study was the examination of cyto- and genotoxic effect of caffeic acid on Escherichia coli K-12 recA::gfp strain treated with dacarbazine. Obtained results indicate that dacarbazine and caffeic acid influenced the reactivity of recA promoter and modulate the level of gfp expression in genetic construct rrcA::gfpmut2 in E. coli K-12. Simultaneuos administration of dacarbazine with caffeic acid caused the stronger inhibition of the bacteria growth than the dacarbazine and caffeic acid separated administration to bacteria cells. The simultaneous effect of the both tested chemicals - dacarbazine and caffeic acid indicated (cytostatic effect) anticancer activity in relation to bacteria cells. It suggests, that combination of known anticancer drug - dacarbazine w ith caffeic acid exerted synergistic cytotoxic and genotoxic effects toward E. coli K- 12 cells and indicated the possibility of usefulness of caffeic acid as a natural adjuvant in anticancer therapy.

Application of bacteria from non-cultivated plants to promote growth, alter root architecture and alleviate salt stress of cotton.

PubMed

Irizarry, I; White, J F

2017-04-01

Cotton seeds are frequently treated with acid to remove fibres and reduce seed-transmitted diseases. This process also eliminates beneficial bacteria on the seed surface. The goal of this research was to seek and apply beneficial bacteria to acid delinted cotton seeds to evaluate their growth-promoting and salt stress alleviating effects in seedlings. Bacteria were isolated from non-cultivated plants in the Malvaceae. Seeds were collected from Portia tree (Thespesia populnea) and wild cotton (Gossypium hirsutum) from coastal and arid areas of Puerto Rico. Bacillus amyloliquefaciens, Curtobacterium oceanosedimentum and Pseudomonas oryzihabitans were inoculated onto acid delinted cotton seeds. Bacteria increased cotton seed germination and length of emerging seedling radicles. Cotton seeds were inoculated with B. amyloliquefaciens to evaluate growth and root architecture of non-stressed and salt stressed seedlings. Inoculating cotton seeds with B. amyloliquefaciens led to a greater percentage of seedlings with expanded cotyledons after 8 days, enhanced primary and lateral root growth, and altered root architecture. Similar results were obtained when okra seeds were inoculated with B. amyloliquefaciens. The data supported the hypothesis that non-cultivated plants in the Malvaceae growing in stressful environments possess bacteria that promote growth, alter root architecture and alleviate salt stress of cotton and okra seedlings. This study demonstrated the effects of applying beneficial bacteria on acid delinted cotton seeds. Inoculating seeds with salt stress alleviating bacteria could improve the growth of crop seedlings that are vulnerable to soil salinization. © 2017 The Society for Applied Microbiology.

Amylolytic bacterial lactic acid fermentation - a review.

PubMed

Reddy, Gopal; Altaf, Md; Naveena, B J; Venkateshwar, M; Kumar, E Vijay

2008-01-01

Lactic acid, an enigmatic chemical has wide applications in food, pharmaceutical, leather, textile industries and as chemical feed stock. Novel applications in synthesis of biodegradable plastics have increased the demand for lactic acid. Microbial fermentations are preferred over chemical synthesis of lactic acid due to various factors. Refined sugars, though costly, are the choice substrates for lactic acid production using Lactobacillus sps. Complex natural starchy raw materials used for production of lactic acid involve pretreatment by gelatinization and liquefaction followed by enzymatic saccharification to glucose and subsequent conversion of glucose to lactic acid by Lactobacillus fermentation. Direct conversion of starchy biomass to lactic acid by bacteria possessing both amylolytic and lactic acid producing character will eliminate the two step process to make it economical. Very few amylolytic lactic acid bacteria with high potential to produce lactic acid at high substrate concentrations are reported till date. In this view, a search has been made for various amylolytic LAB involved in production of lactic acid and utilization of cheaply available renewable agricultural starchy biomass. Lactobacillus amylophilus GV6 is an efficient and widely studied amylolytic lactic acid producing bacteria capable of utilizing inexpensive carbon and nitrogen substrates with high lactic acid production efficiency. This is the first review on amylolytic bacterial lactic acid fermentations till date.

Bacillus spp. produce antibacterial activities against lactic acid bacteria that contaminate fuel ethanol plants

USDA-ARS?s Scientific Manuscript database

Lactic acid bacteria (LAB) frequently contaminate commercial fuel ethanol fermentations, reducing yields and decreasing profitability of biofuel production. Microorganisms from environmental sources in different geographic regions of Thailand were tested for antibacterial activity against LAB. Fou...

Disease notes - Bacterial root rot

USDA-ARS?s Scientific Manuscript database

Bacterial root rot initiated by lactic acid bacteria, particularly Leuconostoc, occurs every year in Idaho sugarbeet fields. Hot fall weather seems to make the problem worse. Although Leuconostoc initiates the rot, other bacteria and yeast frequently invade the tissue as well. The acetic acid bac...

Detection of Mannitol Formation by Bacteria

PubMed Central

Chalfan, Y.; Levy, R.; Mateles, R. I.

1975-01-01

A test is described by means of which formation of mannitol from fructose by lactic acid bacteria can be readily detected. The test is based on removal of interference of residual fructose by dehydration with hydrochloric acid followed by thin-layer chromatography. PMID:1101827

Oxalic Acid from Lentinula edodes Culture Filtrate: Antimicrobial Activity on Phytopathogenic Bacteria and Qualitative and Quantitative Analyses

PubMed Central

Kwak, A-Min; Lee, In-Kyoung; Lee, Sang-Yeop

2016-01-01

The culture filtrate of Lentinula edodes shows potent antimicrobial activity against the plant pathogenic bacteria Ralstonia solanacearum. Bioassay-guided fractionation was conducted using Diaion HP-20 column chromatography, and the insoluble active compound was not adsorbed on the resin. Further fractionation by high-performance liquid chromatography (HPLC) suggested that the active compounds were organic acids. Nine organic acids were detected in the culture filtrate of L. edodes; oxalic acid was the major component and exhibited antibacterial activity against nine different phytopathogenic bacteria. Quantitative analysis by HPLC revealed that the content of oxalic acid was higher in the water extract from spent mushroom substrate than in liquid culture. This suggests that the water extract of spent L. edodes substrate is an eco-friendly control agent for plant diseases. PMID:28154495

The role of oxygen in the liquid fermentation of wheat bran.

PubMed

Savolainen, Otto I; Coda, Rossana; Suomi, Katja; Katina, Kati; Juvonen, Riikka; Hanhineva, Kati; Poutanen, Kaisa

2014-06-15

The extensive use of wheat bran as a food ingredient is limited due to its bitter taste and hard texture. To overcome these, some preprocessing methods, such as fermentation with yeast and lactic acid bacteria or enzymatic treatments have been proposed. The current work studied microbial communities, acidification, ethanol formation and metabolite profile of wheat bran fermented in either aerated or anaerobic conditions. In aerated conditions, yeasts grew better and the production of organic acids was smaller, and hence pH was higher. In anaerobic conditions, lactic acid bacteria and endogenous heterotrophic bacteria grew better. Aeration had a large effect on the sourdough metabolite profile, as analyzed by UPLC-qTOF-MS. Anaerobic conditions induced degradation of ferulic and caffeic acids, whereas the amount of sinapic acid increased. Aeration caused degradation of amino acids and hydroxycinnamic acid derivatives of polyamines. The results suggest that the control of oxygen could be used for tailoring the properties of bran sourdough. Copyright © 2013 Elsevier Ltd. All rights reserved.

Formation of Guaiacol by Spoilage Bacteria from Vanillic Acid, a Product of Rice Koji Cultivation, in Japanese Sake Brewing.

PubMed

Ito, Toshihiko; Konno, Mahito; Shimura, Yoichiro; Watanabe, Seiei; Takahashi, Hitoshi; Hashizume, Katsumi

2016-06-08

The formation of guaiacol, a potent phenolic off-odor compound in the Japanese sake brewing process, was investigated. Eight rice koji samples were analyzed, and one contained guaiacol and 4-vinylguaiacol (4-VG) at extraordinarily high levels: 374 and 2433 μg/kg dry mass koji, respectively. All samples contained ferulic and vanillic acids at concentrations of mg/kg dry mass koji. Guaiacol forming microorganisms were isolated from four rice koji samples. They were identified as Bacillus subtilis, B. amyloliquefaciens/subtilis, and Staphylococcus gallinarum using 16S rRNA gene sequence. These spoilage bacteria convert vanillic acid to guaiacol and ferulic acid to 4-VG. However, they convert very little ferulic acid or 4-VG to guaiacol. Nine strains of koji fungi tested produced vanillic acid at the mg/kg dry mass koji level after cultivation. These results indicated that spoilage bacteria form guaiacol from vanillic acid, which is a product of koji cultivation in the sake brewing process.

Direct quantitation of fatty acids present in bacteria and fungi: stability of the cyclopropane ring to chlorotrimethylsilane.

PubMed

Eras, Jordi; Oró, Robert; Torres, Mercè; Canela, Ramon

2008-07-09

The stability of the cyclopropane ring and the fatty acid composition of microbial cells were determined using chlorotrimethylsilane as reagent with three different conditions 80 degrees C for 1 h, 60 degrees C for 1 h, and 60 degrees C for 2 h. Chlorotrimethylsilane permits a simultaneous extraction and derivatization of fatty acids. A basic method was used as reference. The bacteria, Escherichia coli, Burkholderia cepacia, and Lactobacillus brevis, and fungi Aspergillus niger and Gibberella fujikuroi were used. The stability of the cyclopropane ring on acidic conditions was tested using the cyclopropanecarboxylic acid and a commercial mixture of bacteria fatty acid methyl esters (BAME). Fisher's least significant difference test showed significant differences among the methods. The method using chlorotrimethylsilane and 1-pentanol for 1 h at 80 degrees C gave the best results in cyclopropane, hydroxyl, and total fatty acid recoveries. This procedure allows the fast and easy one-step direct extraction derivatization.

Lactic acid bacteria population dynamics during spontaneous fermentation of radish (Raphanus sativus L.) roots in brine.

PubMed

Pardali, Eleni; Paramithiotis, Spiros; Papadelli, Marina; Mataragas, Marios; Drosinos, Eleftherios H

2017-06-01

The aim of the present study was to assess the microecosystem development and the dynamics of the lactic acid bacteria population during spontaneous fermentation of radish (Raphanus sativus L.) roots in brine at 20 and 30 °C. In both temperatures, lactic acid bacteria prevailed the fermentation; as a result, the pH value was reduced to ca. 3.6 and total titrable acidity increased to ca. 0.4% lactic acid. Enterococci population increased and formed a secondary microbiota while pseudomonads, Enterobacteriaceae and yeasts/molds populations were below enumeration limit already before the middle of fermentation. Pediococcus pentosaceus dominated during the first days, followed by Lactobacillus plantarum that prevailed the fermentation until the end. Lactobacillus brevis was also detected during the final days of fermentation. A succession at sub-species level was revealed by the combination of RAPD-PCR and rep-PCR analyses. Glucose and fructose were the main carbohydrates detected in brine and were metabolized into lactic acid, acetic acid and ethanol.

Differential Effects of a Food-Based Conditioned Inhibitor on Food- or Cocaine-Seeking Behavior

ERIC Educational Resources Information Center

Lombas, Andres S.; Kearns, David N.; Weiss, Stanley J.

2008-01-01

The present experiment compared the effects of a food-based conditioned inhibitor on food seeking vs. cocaine seeking behavior. In two groups of rats, the A+/AB- Pavlovian conditioned inhibition procedure was used to create a conditioned inhibitor for food. Then, for one group of rats (Food-Food Group), a click stimulus was established as an…

PCR detection of thermophilic spore-forming bacteria involved in canned food spoilage.

PubMed

Prevost, S; Andre, S; Remize, F

2010-12-01

Thermophilic bacteria that form highly heat-resistant spores constitute an important group of spoilage bacteria of low-acid canned food. A PCR assay was developed in order to rapidly trace these bacteria. Three PCR primer pairs were designed from rRNA gene sequences. These primers were evaluated for the specificity and the sensitivity of detection. Two primer pairs allowed detection at the species level of Geobacillus stearothermophilus and Moorella thermoacetica/thermoautrophica. The other pair allowed group-specific detection of anaerobic thermophilic bacteria of the genera Thermoanaerobacterium, Thermoanaerobacter, Caldanerobium and Caldanaerobacter. After a single enrichment step, these PCR assays allowed the detection of 28 thermophiles from 34 cans of spoiled low-acid food. In addition, 13 ingredients were screened for the presence of these bacteria. This PCR assay serves as a detection method for strains able to spoil low-acid canned food treated at 55°C. It will lead to better reactivity in the canning industry. Raw materials and ingredients might be qualified not only for quantitative spore contamination, but also for qualitative contamination by highly heat-resistant spores.

Bioreactor for acid mine drainage control

DOEpatents

Zaluski, Marek H.; Manchester, Kenneth R.

2001-01-01

A bioreactor for reacting an aqueous heavy metal and sulfate containing mine drainage solution with sulfate reducing bacteria to produce heavy metal sulfides and reduce the sulfuric acid content of the solution. The reactor is an elongated, horizontal trough defining an inlet section and a reaction section. An inlet manifold adjacent the inlet section distributes aqueous mine drainage solution into the inlet section for flow through the inlet section and reaction section. A sulfate reducing bacteria and bacteria nutrient composition in the inlet section provides sulfate reducing bacteria that with the sulfuric acid and heavy metals in the solution to form solid metal sulfides. The sulfate reducing bacteria and bacteria nutrient composition is retained in the cells of a honeycomb structure formed of cellular honeycomb panels mounted in the reactor inlet section. The honeycomb panels extend upwardly in the inlet section at an acute angle with respect to the horizontal. The cells defined in each panel are thereby offset with respect to the honeycomb cells in each adjacent panel in order to define a tortuous path for the flow of the aqueous solution.

Extraction of manganese from electrolytic manganese residue by bioleaching.

PubMed

Xin, Baoping; Chen, Bing; Duan, Ning; Zhou, Changbo

2011-01-01

Extraction of manganese from electrolytic manganese residues using bioleaching was investigated in this paper. The maximum extraction efficiency of Mn was 93% by sulfur-oxidizing bacteria at 4.0 g/l sulfur after bioleaching of 9days, while the maximum extraction efficiency of Mn was 81% by pyrite-leaching bacteria at 4.0 g/l pyrite. The series bioleaching first by sulfur-oxidizing bacteria and followed by pyrite-leaching bacteria evidently promoted the extraction of manganese, witnessing the maximum extraction efficiency of 98.1%. In the case of sulfur-oxidizing bacteria, the strong dissolution of bio-generated sulfuric acid resulted in extraction of soluble Mn2+, while both the Fe2+ catalyzed reduction of Mn4+ and weak acidic dissolution of Mn2+ accounted for the extraction of manganese with pyrite-leaching bacteria. The chemical simulation of bioleaching process further confirmed that the acid dissolution of Mn2+ and Fe2+ catalyzed reduction of Mn4+ were the bioleaching mechanisms involved for Mn extraction from electrolytic manganese residues. Copyright © 2010 Elsevier Ltd. All rights reserved.

Analysis of the multiple system with chemically peculiar component φ Draconis

NASA Astrophysics Data System (ADS)

Liška, J.

2016-09-01

The star ϕ Dra comprises a spectroscopic binary and a third star that together form a visual triple system. It is one of the brightest chemically peculiar stars of the upper main sequence. Despite these facts, no comprehensive study of its multiplicity has been performed yet. In this work, we present a detailed analysis of the triple system based on available measurements. We use radial velocities taken from four sources in the literature in a re-analysis of the inner spectroscopic binary (Aab). An incorrect value of the orbital period of the inner system Aab about 27 d was accepted in literature more than 40 yr. A new solution of orbit with the 128-d period was determined. Relative position measurements of the outer visual binary system (AB) from Washington Double Star Catalog were compared with known orbital models. Furthermore, it was shown that astrometric motion in system AB is well described by the model of Andrade with a 308-yr orbital period. Parameters of A and B components were utilized to estimate individual brightness for all components and their masses from evolutionary tracks. Although we found several facts which support the gravitational bond between them, unbound solution cannot be fully excluded yet.

Drosophila suzukii (Diptera: Drosophilidae) Contributes to the Development of Sour Rot in Grape.

PubMed

Ioriatti, Claudio; Guzzon, Raffaele; Anfora, Gianfranco; Ghidoni, Franca; Mazzoni, Valerio; Villegas, Tomas Roman; Dalton, Daniel T; Walton, Vaughn M

2018-02-09

This research aimed to more clearly describe the interactions of Drosophila suzukii (Matsumura; Diptera: Drosophilidae) with microorganisms that may contribute to spoilage or quality loss of wine grapes during harvest. Experiments were conducted in controlled laboratory experiments and under field conditions to determine these effects. Laboratory trials determined the role of insect contact and oviposition to vector spoilage bacteria onto wine grapes. In the field, the roles of key organoleptic parameters in grape fruit ripening were assessed to determine their relative contribution to oviposition potential as fruit ripened. Finally, field trials determined the relationships of egg and larval infestation to sour rot levels. Non-ovipositional trials indicated elevated levels of microbiota when D. suzukii was present. D. suzukii oviposition exponentially increased the concentration of acetic acid bacteria. Both incised and sound berries showed a significant increase in concentrations of acetic acid bacteria exposed to D. suzukii. Volatile acidity was higher in treatments infested with D. suzukii. Fruit with only eggs did not develop a significant increase of volatile acidity. Larva-infested grape berries in 9.5% of samples developed higher volatile acidity after 14 d. Sound grape berries were less susceptible to the development of microbiota associated with sour rot and spoilage. D. suzukii oviposition and larval development increase risk of spoilage bacteria vectored by D. suzukii adults. Acetic acid bacteria induced fermentation and produced several volatile compounds contributing to spoilage. Spoilage bacteria may create a positive feedback loop that attracts both D. suzukii and other drosophilids, which may contribute to additional spoilage. © The Author(s) 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Phage-Encoded Colanic Acid-Degrading Enzyme Permits Lytic Phage Infection of a Capsule-Forming Resistant Mutant Escherichia coli Strain

PubMed Central

Kim, Min Soo; Kim, Young Deuk; Hong, Sung Sik; Park, Kwangseo; Ko, Kwan Soo

2014-01-01

In this study, we isolated a bacteriophage T7-resistant mutant strain of Escherichia coli (named S3) and then proceeded to characterize it. The mutant bacterial colonies appeared to be mucoid. Microarray analysis revealed that genes related to colanic acid production were upregulated in the mutant. Increases in colanic acid production by the mutant bacteria were observed when l-fucose was measured biochemically, and protective capsule formation was observed under an electron microscope. We found a point mutation in the lon gene promoter in S3, the mutant bacterium. Overproduction of colanic acid was observed in some phage-resistant mutant bacteria after infection with other bacteriophages, T4 and lambda. Colanic acid overproduction was also observed in clinical isolates of E. coli upon phage infection. The overproduction of colanic acid resulted in the inhibition of bacteriophage adsorption to the host. Biofilm formation initially decreased shortly after infection but eventually increased after 48 h of incubation due to the emergence of the mutant bacteria. Bacteriophage PBECO4 was shown to infect the colanic acid-overproducing mutant strains of E. coli. We confirmed that the gene product of open reading frame 547 (ORF547) of PBECO4 harbored colanic acid-degrading enzymatic (CAE) activity. Treatment of the T7-resistant bacteria with both T7 and PBECO4 or its purified enzyme (CAE) led to successful T7 infection. Biofilm formation decreased with the mixed infection, too. This procedure, using a phage cocktail different from those exploiting solely receptor differences, represents a novel strategy for overcoming phage resistance in mutant bacteria. PMID:25416767

Cotransport of bacteria with hematite in porous media: Effects of ion valence and humic acid.

PubMed

Yang, Haiyan; Ge, Zhi; Wu, Dan; Tong, Meiping; Ni, Jinren

2016-01-01

This study investigated the influence of multiple colloids (hematite and humic acid) on the transport and deposition of bacteria (Escherichia coli) in packed porous media in both NaCl (5 mM) and CaCl2 (1 mM) solutions at pH 6. Due to the alteration of cell physicochemical properties, the presence of hematite and humic acid in cell suspensions significantly affected bacterial transport and deposition in quartz sand. Specifically, the presence of hematite (5 mg/L) decreased cell transport (increased cell deposition) in quartz sand in both NaCl and CaCl2 solutions, which could be attributed to the less negative overall zeta potentials of bacteria induced by the adsorption of positively charged hematite onto cell surfaces. The presence of a low concentration (0.1 mg/L) of humic acid in bacteria and hematite mixed suspensions reduced the adsorption of hematite onto cell surfaces, leading to increased cell transport in quartz sand in NaCl solutions, whereas, in CaCl2 solutions, the presence of 0.1 mg/L humic acid increased the formation of hematite-cell aggregates and thus decreased cell transport in quartz sand. When the concentration of humic acid was increased to 1 mg/L, enhanced cell transport was observed in both NaCl and CaCl2 solutions. The decreased adsorption of hematite onto cell surfaces as well as the competition of deposition sites on quartz sand with bacteria by the suspended humic acid contributed to the increased cell transport. Copyright © 2015 Elsevier Ltd. All rights reserved.

Antagonism of Lactic Acid Bacteria against Phytopathogenic Bacteria

PubMed Central

Visser, Ronèl; Holzapfel, Wilhelm H.; Bezuidenhout, Johannes J.; Kotzé, Johannes M.

1986-01-01

A variety of lactic acid bacteria, isolated from plant surfaces and plant-associated products, were found to be antagonistic to test strains of the phytopathogens Xanthomonas campestris, Erwinia carotovora, and Pseudomonas syringae. Effective “in vitro” inhibition was found both on agar plates and in broth cultures. In pot trials, treatment of bean plants with a Lactobacillus plantarum strain before inoculation with P. syringae caused a significant reduction of the disease incidence. Images PMID:16347150

Method for construction of bacterial strains with increased succinic acid production

DOEpatents

Donnelly, Mark I.; Sanville-Millard, Cynthia; Chatterjee, Ranjini

2000-01-01

A fermentation process for producing succinic acid is provided comprising selecting a bacterial strain that does not produce succinic acid in high yield, disrupting the normal regulation of sugar metabolism of said bacterial strain, and combining the mutant bacterial strain and selected sugar in anaerobic conditions to facilitate production of succinic acid. Also provided is a method for changing low yield succinic acid producing bacteria to high yield succinic acid producing bacteria comprising selecting a bacterial strain having a phosphotransferase system and altering the phosphotransferase system so as to allow the bacterial strain to simultaneously metabolize different sugars.

Application of acid whey and set milk to marinate beef with reference to quality parameters and product safety.

PubMed

Wójciak, Karolina M; Krajmas, Paweł; Solska, Elżbieta; Dolatowski, Zbigniew J

2015-01-01

The aim of the study was to evaluate the potential of acid whey and set milk as a marinade in the traditional production of fermented eye round. Studies involved assaying pH value, water activity (aw), oxidation-reduction potential and TBARS value, colour parameters in CIE system (L*, a*, b*), assaying the number of lactic acid bacteria and certain pathogenic bacteria after ripening process and after 60-day storing in cold storage. Sensory analysis and analysis of the fatty acids profile were performed after completion of the ripening process. Analysis of pH value in the products revealed that application of acid whey to marinate beef resulted in increased acidity of ripening eye round (5.14). The highest value of the colour parameter a* after ripening process and during storage was observed in sample AW (12.76 and 10.07 respectively), the lowest on the other hand was observed in sample SM (10.06 and 7.88 respectively). The content of polyunsaturated fatty acids (PUFA) was higher in eye round marinated in acid whey by approx. 4% in comparison to other samples. Application of acid whey to marinade beef resulted in increased share of red colour in general colour tone as well as increased oxidative stability of the product during storage. It also increased the content of polyunsaturated fatty acids (PUFA) in the product. All model products had high content of lactic acid bacteria and there were no pathogenic bacteria such as: L. monocytogenes, Y. enterocolitica, S. aureus, Clostridium sp.

[Clinical usefulness of urine-formed elements' information obtained from bacteria detection by flow cytometry method that uses nucleic acid staining].

PubMed

Nakagawa, Hiroko; Yuno, Tomoji; Itho, Kiichi

2009-03-01

Recently, specific detection method for Bacteria, by flow cytometry method using nucleic acid staining, was developed as a function of automated urine formed elements analyzer for routine urine testing. Here, we performed a basic study on this bacteria analysis method. In addition, we also have a comparison among urine sediment analysis, urine Gram staining and urine quantitative cultivation, the conventional methods performed up to now. As a result, the bacteria analysis with flow cytometry method that uses nucleic acid staining was excellent in reproducibility, and higher sensitivity compared with microscopic urinary sediment analysis. Based on the ROC curve analysis, which settled urine culture method as standard, cut-off level of 120/microL was defined and its sensitivity = 85.7%, specificity = 88.2%. In the analysis of scattergram, accompanied with urine culture method, among 90% of rod positive samples, 80% of dots were appeared in the area of 30 degrees from axis X. In addition, one case even indicated that analysis of bacteria by flow cytometry and scattergram of time series analysis might be helpful to trace the progress of causative bacteria therefore the information supposed to be clinically significant. Reporting bacteria information with nucleic acid staining flow cytometry method is expected to contribute to a rapid diagnostics and treatment of urinary tract infections. Besides, the contribution to screening examination of microbiology and clinical chemistry, will deliver a more efficient solution to urine analysis.

Iso-branched 2- and 3-hydroxy fatty acids as characteristic lipid constituents of some gliding bacteria.

PubMed Central

Fautz, E; Rosenfelder, G; Grotjahn, L

1979-01-01

The fatty acids present in the total hydrolysates of several gliding bacteria (Myxococcus fulvus, Stigmatella aurantiaca, Cytophaga johnsonae, Cytophaga sp. strain samoa and Flexibacter elegans) were analyzed by combined gas-liquid chromatography and mass spectrometry. In addition to 13-methyl-tetradecanoic acid, 15-methyl-hexadecanoic acid, hexadecanoic acid, and hexadecenoic acid, 2- and 3-hydroxy fatty acids comprised up to 50% of the total fatty acids. The majority was odd-numbered and iso-branched. Small amounts of even-numbered and unbranched fatty acids were also present. Whereas 2-hydroxy-15-methyl hexadecanoic acid was characteristic for myxobacteria, 2-hydroxy-13-methyl-tetradecanoic acid, 3-hydroxy-13-methyl-tetradecanoic acid, and 3-hydroxy-15-methyl-hexadecanoic acid were dominant in the Cytophaga-Flexibacter group. PMID:118159

Antimicrobial Activity and Chemical Composition of "Kpètè-Kpètè": A Starter of Benin Traditional Beer Tchoukoutou.

PubMed

N'tcha, Christine; Sina, Haziz; Kayodé, Adéchola Pierre Polycarpe; Gbenou, Joachim D; Baba-Moussa, Lamine

2017-01-01

The aim of this study was to investigate the antibacterial effect of the crude starter " kpètè-kpètè " and lactic acid bacteria used during the production of "tchoukoutou." To achieve this, a total of 11 lactic acid bacteria and 40 starter samples were collected from four communes. The samples were tested on 29 gram + and - strains by disk diffusion method. The minimum inhibitory and bactericidal concentrations of starter and lactic acid bacteria were determined by conventional methods. Organic acids, sugar, and volatile compounds were determined using the HPLC method. The "kpètè-kpètè" displays a high antibacterial activity against the tested strains. The most sensitive strain was S. epidermidis (12.5 mm) whereas the resistance strain was Proteus mirabilis (8 mm). All the tested ferment has not any inhibitory effect on Enterococcus faecalis . The lactic acid bacteria isolates of Parakou showed the highest (17.48 mm) antibacterial activity whereas the smallest diameter was obtained with the ferment collected from Boukoumbé (9.80 mm). The starters' chemical screening revealed the presence of tannins, anthocyanin flavonoids, triterpenes, steroids, reducing compounds, and mucilage O-glycosides. These compounds are probably the source of recorded inhibition effect. The lactic acid bacteria of the "kpètè-kpètè" could be used to develop a food ingredient with probiotic property.

Antibacterial efficacy of triple-layered poly(lactic-co-glycolic acid)/nanoapatite/lauric acid guided bone regeneration membrane on periodontal bacteria.

PubMed

Saarani, Nur Najiha; Jamuna-Thevi, Kalitheerta; Shahab, Neelam; Hermawan, Hendra; Saidin, Syafiqah

2017-05-31

A guided bone regeneration (GBR) membrane has been extensively used in the repair and regeneration of damaged periodontal tissues. One of the main challenges of GBR restoration is bacterial colonization on the membrane, constitutes to premature membrane degradation. Therefore, the purpose of this study was to investigate the antibacterial efficacy of triple-layered GBR membrane composed of poly(lactic-co-glycolic acid) (PLGA), nanoapatite (NAp) and lauric acid (LA) with two types of Gram-negative periodontal bacteria, Fusobacterium nucleatum and Porphyromonas gingivalis through a disc diffusion and bacterial count tests. The membranes exhibited a pattern of growth inhibition and killing effect against both bacteria. The increase in LA concentration tended to increase the bactericidal activities which indicated by higher diameter of inhibition zone and higher antibacterial percentage. It is shown that the incorporation of LA into the GBR membrane has retarded the growth and proliferation of Gram-negative periodontal bacteria for the treatment of periodontal disease.

Growth cycle of Helicobacter pylori in gastric mucous layer.

PubMed

Nakazawa, Teruko

2002-12-01

Helicobacter pylori bacterium is characterized by its strong urease activity. Our studies on the role of H. pylori urease revealed; (i) it is essential for colonization, (ii) exogenous urea is required for acid resistance, (iii) the bacteria have the ability to move toward urea and sodium bicarbonate, (iv) urea hydrolysis accelerates chemotactic locomotion, and (v) decay of urease mRNA to accomplish the active center is pH-regulated; i.e., the mRNA is stabilized and destabilized under acidic and neutral conditions, respectively. Based on the above results, I propose the growth cycle of H. pylori in gastric mucous layer. H. pylori bacteria proliferate on the epithelial cell surface by utilizing nutrients derived from degraded cells. Proliferated bacteria leave the cell surface to pH-variable region where they encounter strong acid. Urease is activated with simultaneous opening of UreI channel so that urea is hydrolyzed to neutralize acid. Chemotaxis of H. pylori toward urea and sodium bicarbonate that are abundant on the cell surface is accelerated by urea hydrolysis so that the bacteria go back to the cell surface for the next round of proliferation. This growth cycle may allow the bacteria to infect persistently in the stomach.

Freeze-drying of lactic acid bacteria.

PubMed

Fonseca, Fernanda; Cenard, Stéphanie; Passot, Stéphanie

2015-01-01

Lactic acid bacteria are of great importance for the food and biotechnology industry. They are widely used as starters for manufacturing food (e.g., yogurt, cheese, fermented meats, and vegetables) and probiotic products, as well as for green chemistry applications. Freeze-drying or lyophilization is a convenient method for preservation of bacteria. By reducing water activity to values below 0.2, it allows long-term storage and low-cost distribution at suprazero temperatures, while minimizing losses in viability and functionality. Stabilization of bacteria via freeze-drying starts with the addition of a protectant solution to the bacterial suspension. Freeze-drying includes three steps, namely, (1) freezing of the concentrated and protected cell suspension, (2) primary drying to remove ice by sublimation, and (3) secondary drying to remove unfrozen water by desorption. In this chapter we describe a method for freeze-drying of lactic acid bacteria at a pilot scale, thus allowing control of the process parameters for maximal survival and functionality recovery.

In situ biodegradation of naphthenic acids in oil sands tailings pond water using indigenous algae-bacteria consortium.

PubMed

Mahdavi, Hamed; Prasad, Vinay; Liu, Yang; Ulrich, Ania C

2015-01-01

In this study, the biodegradation of total acid-extractable organics (TAOs), commonly called naphthenic acids (NAs), was investigated. An indigenous microbial culture containing algae and bacteria was taken from the surface of a tailings pond and incubated over the course of 120days. The influence of light, oxygen and the presence of indigenous algae and bacteria, and a diatom (Navicula pelliculosa) on the TAO removal rate were elucidated. The highest biodegradation rate was observed with bacteria growth only (without light exposure) with a half-life (t(1/2)) of 203days. The algae-bacteria consortium enhanced the detoxification process, however, bacterial biomass played the main role in toxicity reduction. Principal component analysis (PCA) conducted on FT-IR spectra, identified functional groups and bonds (representing potential markers for biotransformation of TAOs) as follows: hydroxyl, carboxyl and amide groups along with CH, arylH, arylOH and NH bonds. Copyright © 2015 Elsevier Ltd. All rights reserved.

Nitrogen-fixing and uricolytic bacteria associated with the gut of Dendroctonus rhizophagus and Dendroctonus valens (Curculionidae: Scolytinae).

PubMed

Morales-Jiménez, Jesús; Vera-Ponce de León, Arturo; García-Domínguez, Aidé; Martínez-Romero, Esperanza; Zúñiga, Gerardo; Hernández-Rodríguez, César

2013-07-01

The bark beetles of the genus Dendroctonus feed on phloem that is a nitrogen-limited source. Nitrogen fixation and nitrogen recycling may compensate or alleviate such a limitation, and beetle-associated bacteria capable of such processes were identified. Raoultella terrigena, a diazotrophic bacteria present in the gut of Dendroctonus rhizophagus and D. valens, exhibited high acetylene reduction activity in vitro with different carbon sources, and its nifH and nifD genes were sequenced. Bacteria able to recycle uric acid were Pseudomonas fluorescens DVL3A that used it as carbon and nitrogen source, Serratia proteomaculans 2A CDF and Rahnella aquatilis 6-DR that used uric acid as sole nitrogen source. Also, this is the first report about the uric acid content in whole eggs, larvae, and adults (male and female) samples of the red turpentine beetle (Dendroctonus valens). Our results suggest that the gut bacteria of these bark beetles could contribute to insect N balance.

Effect of high pressure treatment on microbiological quality of Indian white prawn (Fenneropenaeus indicus) during chilled storage.

PubMed

Ginson, J; Panda, Satyen Kumar; Bindu, J; Kamalakanth, C K; Srinivasa Gopal, T K

2015-04-01

High pressure treatment of 250 MPa for 6 min at 25 °C was applied to headless Indian white prawn (Fenneropenaeus indicus) to evaluate changes in microbiological characteristics of the species during chilled storage. Changes in load of mesophilic bacteria, psychrotrophic bacteria, proteolytic bacteria, Enterobacteriaceae, Pseudomonas spp., H2S producing bacteria, lactic acid bacteria, Brochothrix thermosphacta and yeast & mold were estimated in pressurized and un-pressurized samples during chilled storage. All microbes were reduced significantly after high pressure treatment and there was significant difference in microbial quality of control and high pressure treated samples in the entire duration of chilled storage (p < 0.05). There was delay in the growth of Enterobacteriaceae and H2S producing bacteria up to 6th and 9th day of storage, respectively in high pressure treated samples. In high pressure treated sample, no lag phase (λ) was observed for psychrotrophic bacteria, H2S producing bacteria, B. thermosphacta, Pseudomonas spp. and lactic acid bacteria; however, other bacteria showed a reduced lag phase during chilled storage. Kinetic parameter such as specific growth rate (μmax) in high pressure treated samples was significantly reduced in most of the bacterial groups except for psychrotrophic bacteria, Enterobacteriaceae and lactic acid bacteria. Mesophilic bacterial count of control samples crossed the marginal limit of acceptability on 12th day and unacceptable limit on 18th day of storage, whereas high pressure treated samples never breached the acceptability limit during entire duration of chilled storage. The present study indicated that application of high pressure processing can be used to improve microbial quality of Indian white prawn and extend the chilled storage life. Copyright © 2014 Elsevier Ltd. All rights reserved.

Sensitive change of iso-branched fatty acid (iso-15:0) in Bacillus pumilus PAMC 23174 in response to environmental changes.

PubMed

Yi, Da-Hye; Sathiyanarayanan, Ganesan; Seo, Hyung Min; Kim, Jung-Ho; Bhatia, Shashi Kant; Kim, Yun-Gon; Park, Sung-Hee; Jung, Ji-Young; Lee, Yoo Kyung; Yang, Yung-Hun

2016-01-01

In this study, the environmental adaptive metabolic processes were investigated using a psychrotrophic polar bacterium Bacillus pumilus PAMC 23174 in response to various temperatures and nutrients, especially in regard to the synthesis of fatty acids. Fatty acid methyl ester analysis was performed using gas chromatography-mass spectrometry and we found that a sensitive changes in iso-branched fatty acid (iso-15:0) synthesis occurred when adjusting the nutritional ratio of branched chain fatty acids (anteiso/iso) with different temperatures, resulting in a change in the balance of anteiso- and iso-form fatty acids. We also observed that this Arctic bacterium preferred amino acid leucine for the synthesis of fatty acids. The increased and decreased synthesis of iso-form fatty acids in response to different temperatures and leucine preference, changes the fatty acid ratio in bacteria, which further affects the membrane fluidity and it is also directly correlated with survival of bacteria in an extreme environment. Hence, this study suggests that B. pumilus PAMC 23174 is a potential model organism for the analysis of the unique ecological adaptations of polar bacteria in changing and the extreme environments.

Acrylic acid removal by acrylic acid utilizing bacteria from acrylonitrile-butadiene-styrene resin manufactured wastewater treatment system.

PubMed

Wang, C C; Lee, C M

2006-01-01

The aim of this study is to isolate the acrylic acid utilizing bacteria from the ABS resin manufactured wastewater treatment system. The bacteria should have the ability to remove acrylic acid and tolerate the acrylonitrile and acrylamide toxicity. The aim is also to understand the performance of isolated pure strain for treating different initial acrylic acid concentrations from synthetic wastewater. The results are: twenty strains were isolated from the ABS resin manufactured wastewater treatment system and twelve of them could utilize 600 mg/l acrylic acid for growth. Seven of twelve strains could tolerate the acrylonitrile and acrylamide toxicity, when the concentration was below 300 mg/l. Bacillus thuringiensis was one of the seven strains and the optimum growth temperature was 32 degrees C. Bacillus thuringiensis could utilize acrylic acid for growth, when the initial acrylic acid concentration was below 1,690.4 mg/l. Besides this, when the initial acrylic acid concentration was below 606.8 mg/l, the acrylic acid removal efficiency exceeded 96.3%. Bacillus thuringiensis could tolerate 295.7 mg/l acrylamide and 198.4 mg/l acrylonitrile toxicity but could not tolerate 297.3 mg/l epsilon-caprolactam.

Metal Ion-Assembled Micro-Collagen Heterotrimers

PubMed Central

LeBruin, Lyndelle Toni; Banerjee, Sunandan; O'Rourke, Bruce Delany; Case, Martin Ashley

2011-01-01

Collagen mimetic peptides (CMPs) provide critical insight into the assembly, stability and structure of the triple helical collagen protein. The majority of natural fibrous collagens are aab or abc heterotrimers, yet few examples of heterotrimeric CMPs have been reported. Previously CMP heterotrimers have only been accessible by total syntheses or by introducing complementary interstrand electrostatic or steric interactions. Here we describe an abc CMP heterotrimer in which each contributing CMP consists of only three amino acids: glycine, proline and 4-hydroxyproline. Assembly of the heterotrimeric triple helix is directed by a combination of metal-ion coordination to set the relative register of the CMPs, and minimization of valence frustration to direct heterotrimerization. Assembly of the four-component mixture is facile and extremely rapid, and equilibration to the abc heterotrimer occurs within a few hours at modestly elevated temperatures. The melting temperatures of the metal-assembled collagen trimers are higher by some 30 °C than the apopeptide assemblies. Two iterations of the design are described, and the outcomes suggest possibilities for designing self-assembling abc and abb heterotrimers. PMID:21590759

Ultrastructural localization of acid phosphatase in some bacteria, after treatment with Lubrol W1.

PubMed

Cherepova, N; Spasova, D

1996-01-01

The ultracytochemical localization of acid phosphatase from some bacteria (Listeria monocytogenes, Salmonella typhimurium, Pseudomonas pseudomallei and Pseudomonas aeruginosa) was dependent on the changes in the lipoprotein content of the membranes as a result of the action of the Lubrol W1.

Effects of lactic acid bacteria contamination on lignocellulosic ethanol fermentation

USDA-ARS?s Scientific Manuscript database

Slower fermentation rates, mixed sugar compositions, and lower sugar concentrations may make lignocellulosic fermentations more susceptible to contamination by lactic acid bacteria (LAB), which is a common and costly problem to the corn-based fuel ethanol industry. To examine the effects of LAB con...

Discrimination of wine lactic acid bacteria by Raman spectroscopy.

PubMed

Rodriguez, Susan B; Thornton, Mark A; Thornton, Roy J

2017-08-01

Species of Lactobacillus, Pediococcus, Oenococcus, and Leuconostoc play an important role in winemaking, as either inoculants or contaminants. The metabolic products of these lactic acid bacteria have considerable effects on the flavor, aroma, and texture of a wine. However, analysis of a wine's microflora, especially the bacteria, is rarely done unless spoilage becomes evident, and identification at the species or strain level is uncommon as the methods required are technically difficult and expensive. In this work, we used Raman spectral fingerprints to discriminate 19 strains of Lactobacillus, Pediococcus, and Oenococcus. Species of Lactobacillus and Pediococcus and strains of O. oeni and P. damnosus were classified with high sensitivity: 86-90 and 84-85%, respectively. Our results demonstrate that a simple, inexpensive method utilizing Raman spectroscopy can be used to accurately identify lactic acid bacteria isolated from wine.

Selection of bacteriocin producer strains of lactic acid bacteria from a dairy environment.

PubMed

Lasagno, M; Beoleito, V; Sesma, F; Raya, R; Font de Valdez, G; Eraso, A

2002-01-01

Two strains showing bacteriocin production were selected from a total of 206 lactic acid bacteria isolated from samples of milk, milk serum, whey and homemade cheeses in Southern Cordoba, Argentina. This property was detected by means of well diffusion assays. The strains were identified as Enterococcus hirae and Enterococcus durans. The protein nature of those substances was proved by showing their sensitivity to type IV and XXV proteases, papaine, trypsin, pepsin and K proteinase. The bacteriocins inhibited the growth of Listeria monocytogenes, Bacillus cereus, Clostridium perfringes and two strains of Staphylococcus aureus, an A-enterotoxin and a B-enterotoxin producers. All of these bacteria are common pathogens usually associated with food borne diseases (ETA). These lactic acid bacteria or their bacteriocins could be suitable candidates for food preservation and specially useful in the our regional dairy industry.

Characterization of probiotic bacteria involved in fermented milk processing enriched with folic acid.

PubMed

Wu, Zhen; Wu, Jing; Cao, Pei; Jin, Yifeng; Pan, Daodong; Zeng, Xiaoqun; Guo, Yuxing

2017-06-01

Yogurt products fermented with probiotic bacteria are a consumer trend and a challenge for functional food development. So far, limited research has focused on the behavior of the various probiotic strains used in milk fermentation. In the present study, we characterized folic acid production and the sensory and textural characteristics of yogurt products fermented with probiotic bacteria. Yogurt fermented with Lactobacillus plantarum had improved nutrient content and sensory and textural characteristics, but the presence of L. plantarum significantly impaired the growth and survival of Lactobacillus delbrueckii ssp. bulgaricus during refrigerated storage. Overall, L. plantarum was a good candidate for probiotic yogurt fermentation; further studies are needed to understand the major metabolite path of lactic acid bacteria in complex fermentation. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Polyunsaturated fatty acids in marine bacteria and strategies to enhance their production.

PubMed

Moi, Ibrahim Musa; Leow, Adam Thean Chor; Ali, Mohd Shukuri Mohamad; Rahman, Raja Noor Zaliha Raja Abd; Salleh, Abu Bakar; Sabri, Suriana

2018-05-10

Polyunsaturated fatty acids (PUFAs) play an important role in human diet. Despite the wide-ranging importance and benefits from heart health to brain functions, humans and mammals cannot synthesize PUFAs de novo. The primary sources of PUFA are fish and plants. Due to the increasing concerns associated with food security as well as issues of environmental contaminants in fish oil, there has been considerable interest in the production of polyunsaturated fatty acids from alternative resources which are more sustainable, safer, and economical. For instance, marine bacteria, particularly the genus of Shewanella, Photobacterium, Colwellia, Moritella, Psychromonas, Vibrio, and Alteromonas, are found to be one among the major microbial producers of polyunsaturated fatty acids. Recent developments in the area with a focus on the production of polyunsaturated fatty acids from marine bacteria as well as the metabolic engineering strategies for the improvement of PUFA production are discussed.

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

Effects of levan-type fructan on growth performance, nutrient digestibility, diarrhoea scores, faecal shedding of total lactic acid bacteria and coliform bacteria, and faecal gas emission in weaning pigs.

PubMed

Lei, Xin Jian; Kim, Yong Min; Park, Jae Hong; Baek, Dong Heon; Nyachoti, Charles Martin; Kim, In Ho

2018-03-01

The use of antibiotics as growth promoters in feed has been fully or partially banned in several countries. The objective of this study was to evaluate effects of levan-type fructan on growth performance, nutrient digestibility, faecal shedding of lactic acid bacteria and coliform bacteria, diarrhoea scores, and faecal gas emission in weaning pigs. A total of 144 weaning pigs [(Yorkshire × Landrace) × Duroc] were randomly allocated to four diets: corn-soybean meal-based diets supplemented with 0, 0.1, 0.5, or 1.0 g kg -1 levan-type fructan during this 42-day experiment. During days 0 to 21 and 0 to 42, average daily gain and average daily feed intake were linearly increased (P < 0.01) with increasing dietary levan-type fructan inclusion. The apparent total tract digestibility of dry matter, crude protein, and gross energy were linearly increased (P < 0.001) with increasing dietary levan-type fructan content. With increasing levels of levan-type fructan, faecal lactic acid bacteria counts were linearly increased (P = 0.001). The results indicate that dietary supplementation with increasing levan-type fructan enhanced growth performance, improved nutrient digestibility, and increased faecal lactic acid bacteria counts in weaning pigs linearly. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Influence of membrane fatty acid composition and fluidity on airborne survival of Escherichia coli.

PubMed

Ng, Tsz Wai; Chan, Wing Lam; Lai, Ka Man

2018-04-01

Finding ways to predict and control the survival of bacterial aerosols can contribute to the development of ways to alleviate a number of crucial microbiological problems. Significant damage in the membrane integrity of Escherichia coli during aerosolization and airborne suspension has been revealed which has prompted the question of how the membrane fatty acid composition and fluidity influence the survival of airborne bacteria. Two approaches of using isogenic mutants and different growth temperatures were selected to manipulate the membrane fatty acid composition of E. coli before challenging the bacteria with different relative humidity (RH) levels in an aerosol chamber. Among the mutants (fabR - , cfa. fadA - ), fabR - had the lowest membrane fluidity index (FI) and generally showed a higher survival than the parental strain. Surprisingly, its resistance to airborne stress was so strong that its viability was fully maintained even after airborne suspension at 40% RH, a harsh RH level to bacterial survival. Moreover, E. coli cultured at 20 °C with a higher FI than that at 30 and 37 °C generally had a lower survival after aerosolization and airborne suspension. Unlike FI, individual fatty acid and cyclopropane fatty acid composition did not relate to the bacterial survival. Lipid peroxidation of the membrane was undetected in all the bacteria. Membrane fluidity plays a stronger role in determining the bacteria survival during airborne suspension than during aerosolization. Certain relationships between FI and bacteria survival were identified, which could help predict the transmission of bacteria under different conditions.

[Identification of new conserved and variable regions in the 16S rRNA gene of acetic acid bacteria and acetobacteraceae family].

PubMed

Chakravorty, S; Sarkar, S; Gachhui, R

2015-01-01

The Acetobacteraceae family of the class Alpha Proteobacteria is comprised of high sugar and acid tolerant bacteria. The Acetic Acid Bacteria are the economically most significant group of this family because of its association with food products like vinegar, wine etc. Acetobacteraceae are often hard to culture in laboratory conditions and they also maintain very low abundances in their natural habitats. Thus identification of the organisms in such environments is greatly dependent on modern tools of molecular biology which require a thorough knowledge of specific conserved gene sequences that may act as primers and or probes. Moreover unconserved domains in genes also become markers for differentiating closely related genera. In bacteria, the 16S rRNA gene is an ideal candidate for such conserved and variable domains. In order to study the conserved and variable domains of the 16S rRNA gene of Acetic Acid Bacteria and the Acetobacteraceae family, sequences from publicly available databases were aligned and compared. Near complete sequences of the gene were also obtained from Kombucha tea biofilm, a known Acetobacteraceae family habitat, in order to corroborate the domains obtained from the alignment studies. The study indicated that the degree of conservation in the gene is significantly higher among the Acetic Acid Bacteria than the whole Acetobacteraceae family. Moreover it was also observed that the previously described hypervariable regions V1, V3, V5, V6 and V7 were more or less conserved in the family and the spans of the variable regions are quite distinct as well.

Taxonomic structure of the yeasts and lactic acid bacteria microbiota of pineapple (Ananas comosus L. Merr.) and use of autochthonous starters for minimally processing.

PubMed

Di Cagno, Raffaella; Cardinali, Gainluigi; Minervini, Giovanna; Antonielli, Livio; Rizzello, Carlo Giuseppe; Ricciuti, Patrizia; Gobbetti, Marco

2010-05-01

Pichia guilliermondii was the only identified yeast in pineapple fruits. Lactobacillus plantarum and Lactobacillus rossiae were the main identified species of lactic acid bacteria. Typing of lactic acid bacteria differentiated isolates depending on the layers. L. plantarum 1OR12 and L. rossiae 2MR10 were selected within the lactic acid bacteria isolates based on the kinetics of growth and acidification. Five technological options, including minimal processing, were considered for pineapple: heating at 72 degrees C for 15 s (HP); spontaneous fermentation without (FP) or followed by heating (FHP), and fermentation by selected autochthonous L. plantarum 1OR12 and L. rossiae 2MR10 without (SP) or preceded by heating (HSP). After 30 days of storage at 4 degrees C, HSP and SP had a number of lactic acid bacteria 1000 to 1,000,000 times higher than the other processed pineapples. The number of yeasts was the lowest in HSP and SP. The Community Level Catabolic Profiles of processed pineapples indirectly confirmed the capacity of autochthonous starters to dominate during fermentation. HSP and SP also showed the highest antioxidant activity and firmness, the better preservation of the natural colours and were preferred for odour and overall acceptability. Copyright (c) 2009 Elsevier Ltd. All rights reserved.

Reduction of nitrobenzene with alkaline ascorbic acid: Kinetics and pathways.

PubMed

Liang, Chenju; Lin, Ya-Ting; Shiu, Jia-Wei

2016-01-25

Alkaline ascorbic acid (AA) exhibits the potential to reductively degrade nitrobenzene (NB), which is the simplest of the nitroaromatic compounds. The nitro group (NO2(-)) of NB has a +III oxidation state of the N atom and tends to gain electrons. The effect of alkaline pH ranging from 9 to 13 was initially assessed and the results demonstrated that the solution pH, when approaching or above the pKa2 of AA (11.79), would increase reductive electron transfer to NB. The rate equation for the reactions between NB and AA at pH 12 can be described as r=((0.89±0.11)×10(-4) mM(1-(a+b))h(-1))×[NB](a=1.35±0.10)[AA](b=0.89±0.01). The GC/MS analytical method identified nitrosobenzene, azoxybenzene, and azobenzene as NB reduction intermediates, and aniline (AN) as a final product. These experimental results indicate that the alkaline AA reduction of NB to AN mainly proceeds via the direct route, consisting of a series of two-electron or four-electron transfers, and the condensation reaction plays a minor route. Preliminary evaluation of the remediation of spiked NB contaminated soils revealed that maintenance of alkaline pH and a higher water to soil ratio are essential for a successful alkaline AA application. Copyright © 2015 Elsevier B.V. All rights reserved.

Antibacterial activity of Pinus elliottii against anaerobic bacteria present in primary endodontic infections.

PubMed

Caetano da Silva, Sandro Donizete; Mendes de Souza, Maria Gorete; Oliveira Cardoso, Miguel Jorge; da Silva Moraes, Thais; Ambrósio, Sérgio Ricardo; Sola Veneziani, Rodrigo Cássio; Martins, Carlos Henrique G

2014-12-01

Endodontic infections have a polymicrobial nature, but anaerobic bacteria prevail among the infectious microbes. Considering that it is easy to eliminate planktonic bacteria, biofilm-forming bacteria still challenge clinicians during the fight against endodontic diseases. The chemical constituents of the oleoresin of Pinus elliottii, a plant belonging to the family Pinaceae, stand out in the search for biologically active compounds based on natural products with potential application in the treatment of endodontic infections. Indeed, plant oleoresins are an abundant natural source of diterpenes that display significant and well-defined biological activities as well as potential antimicrobial action. In this context, this study aimed to (1) evaluate the in vitro antibacterial activity of the oleoresin, fractions, and subfractions of P. elliottii as well as the action of dehydroabietic acid against 11 anaerobic bacteria that cause endodontic infection in both their planktonic and biofilm forms and (2) assess the in vitro antibiofilm activity of dehydroabietic acid against the same group of bacteria. The broth microdilution technique helped to determine the minimum inhibitory concentration (MIC) of the oleoresin and fractions. This same technique aided determination of the MIC values of nine subfractions of Fraction 1, the most active fraction. The MIC, minimum bactericidal concentration, and antibiofilm activity of dehydroabietic acid against the tested anaerobic bacteria were also examined. The oleoresin and fractions, especially fraction PE1, afforded promising MIC values, which ranged from 0.4 to 50 μg/mL. Concerning the nine evaluated subfractions, PE1.3 and PE1.4 furnished the most noteworthy MIC values, between 6.2 and 100 μg/mL. Dehydroabietic acid displayed antibacterial activity, with MIC values lying from 6.2 to 50 μg/mL, as well as bactericidal effect for all the investigated bacteria, except for Prevotella nigrescens. Assessment of the antibiofilm activity revealed significant results--MICB50 lay between 7.8 and 62.5 μg/mL, and dehydroabietic acid prevented all the evaluated bacteria from forming a biofilm. Hence, the chemical constituents of P. elliottii are promising biomolecules to develop novel therapeutic strategies to fight against endodontic infections. Copyright © 2014 Elsevier Ltd. All rights reserved.

Characterization and application of lactic acid bacteria for tropical silage preparation.

PubMed

Pholsen, Suradej; Khota, Waroon; Pang, Huili; Higgs, David; Cai, Yimin

2016-10-01

Strains TH 14, TH 21 and TH 64 were isolated from tropical silages, namely corn stover, sugar cane top and rice straw, respectively, prepared in Thailand. These strains were selected by low pH growth range and high lactic acid-producing ability, similar to some commercial inoculants. Based on the analysis of 16S ribosomal RNA gene sequence and DNA-DNA relatedness, strain TH 14 was identified as Lactobacillus casei, and strains TH 21 and TH 64 were identified as L. plantarum. Strains TH 14, TH 21, TH 64 and two commercial inoculants, CH (L. plantarum) and SN (L. rhamnosus), were used as additives to fresh and wilted purple Guinea and sorghum silages prepared using a small-scale fermentation method. The number of epiphytic lactic acid bacteria (LAB) in the forages before ensilage was relatively low but the numbers of coliform and aerobic bacteria were higher. Sorghum silages at 30 days of fermentation were all well preserved with low pH (3.56) and high lactic acid production (72.86 g/kg dry matter). Purple Guinea silage inoculated with LAB exhibited reduced count levels of aerobic and coliform bacteria, lower pH, butyric acid and ammonia nitrogen and increased lactic acid concentration, compared with the control. Strain TH 14 more effectively improved lactic acid production compared with inoculants and other strains. © 2016 Japanese Society of Animal Science. © 2016 Japanese Society of Animal Science.

Exploitation of grape marc as functional substrate for lactic acid bacteria and bifidobacteria growth and enhanced antioxidant activity.

PubMed

Campanella, Daniela; Rizzello, Carlo Giuseppe; Fasciano, Cristina; Gambacorta, Giuseppe; Pinto, Daniela; Marzani, Barbara; Scarano, Nicola; De Angelis, Maria; Gobbetti, Marco

2017-08-01

This study aimed at using grape marc for the growth of lactic acid bacteria and bifidobacteria with the perspective of producing a functional ingredient having antioxidant activity. Lactobacillus plantarum 12A and PU1, Lactobacillus paracasei 14A, and Bifidobacterium breve 15A showed the ability to grow on grape marc (GM) based media. The highest bacterial cell density (>9.0 CFU/g) was found in GM added of 1% of glucose (GMG). Compared to un-inoculated and incubated control fermented GMG showed a decrease of carbohydrates and citric acid together with an increase of lactic acid. The content of several free amino acids and phenol compounds differed between samples. Based on the survival under simulated gastro-intestinal conditions, GMG was a suitable carrier of lactic acid bacteria and bifidobacteria strains. Compared to the control, cell-free supernatant (CFS) of fermented GMG exhibited a marked antioxidant activity in vitro. The increased antioxidant activity was confirmed using Caco-2 cell line after inducing oxidative stress, and determining cell viability and radical scavenging activity through MTT and DCFH-DA assays, respectively. Supporting these founding, the SOD-2 gene expression of Caco-2 cells also showed a lowest pro-oxidant effect induced by the four CFS of GMG fermented by lactic acid bacteria and bifidobacteria. Copyright © 2017 Elsevier Ltd. All rights reserved.

Exploitation of vegetables and fruits through lactic acid fermentation.

PubMed

Di Cagno, Raffaella; Coda, Rossana; De Angelis, Maria; Gobbetti, Marco

2013-02-01

Lactic acid fermentation represents the easiest and the most suitable way for increasing the daily consumption of fresh-like vegetables and fruits. Literature data are accumulating, and this review aims at describing the main features of the lactic acid bacteria to be used for fermentation. Lactic acid bacteria are a small part of the autochthonous microbiota of vegetables and fruits. The diversity of the microbiota markedly depends on the intrinsic and extrinsic parameters of the plant matrix. Notwithstanding the reliable value of the spontaneous fermentation to stabilize and preserve raw vegetables and fruits, a number of factors are in favour of using selected starters. Two main options may be pursued for the controlled lactic acid fermentation of vegetables and fruits: the use of commercial/allochthonous and the use of autochthonous starters. Several evidences were described in favour of the use of selected autochthonous starters, which are tailored for the specific plant matrix. Pro-technological, sensory and nutritional criteria for selecting starters were reported as well as several functional properties, which were recently ascribed to autochthonous lactic acid bacteria. The main features of the protocols used for the manufacture of traditional, emerging and innovative fermented vegetables and fruits were reviewed. Tailored lactic acid bacteria starters completely exploit the potential of vegetables and fruits, which enhances the hygiene, sensory, nutritional and shelf life properties. Copyright © 2012 Elsevier Ltd. All rights reserved.

Survival and growth of probiotic lactic acid bacteria in refrigerated pickle products

USDA-ARS?s Scientific Manuscript database

We examined 10 lactic acid bacteria that have been previously characterized for commercial use as probiotic cultures, mostly for dairy products, including 1 Pediococcus and 9 Lactobacilli. Our objectives were to develop a rapid procedure for determining the long-term survivability of these cultures ...

Glucansucrases from lactic acid bacteria which produce water-insoluble polysaccharides from sucrose

USDA-ARS?s Scientific Manuscript database

Dextrans and related glucans produced from sucrose by lactic acid bacteria have been studied for many years and are used in numerous commercial applications and products. Most of these glucans are water-soluble, except for a few notable exceptions from cariogenic Streptococcus spp. and a very small ...

Biochemical and molecular characterization of potential phosphate-solubilizing bacteria in acid sulfate soils and their beneficial effects on rice growth.

PubMed

Panhwar, Qurban Ali; Naher, Umme Aminun; Shamshuddin, Jusop; Jusop, Shamshuddin; Othman, Radziah; Latif, Md Abdul; Ismail, Mohd Razi

2014-01-01

A study was conducted to determine the total microbial population, the occurrence of growth promoting bacteria and their beneficial traits in acid sulfate soils. The mechanisms by which the bacteria enhance rice seedlings grown under high Al and low pH stress were investigated. Soils and rice root samples were randomly collected from four sites in the study area (Kelantan, Malaysia). The topsoil pH and exchangeable Al ranged from 3.3 to 4.7 and 1.24 to 4.25 cmol(c) kg(-1), respectively, which are considered unsuitable for rice production. Total bacterial and actinomycetes population in the acidic soils were found to be higher than fungal populations. A total of 21 phosphate-solubilizing bacteria (PSB) including 19 N2-fixing strains were isolated from the acid sulfate soil. Using 16S rRNA gene sequence analysis, three potential PSB strains based on their beneficial characteristics were identified (Burkholderia thailandensis, Sphingomonas pituitosa and Burkholderia seminalis). The isolated strains were capable of producing indoleacetic acid (IAA) and organic acids that were able to reduce Al availability via a chelation process. These PSB isolates solubilized P (43.65%) existing in the growth media within 72 hours of incubation. Seedling of rice variety, MR 219, grown at pH 4, and with different concentrations of Al (0, 50 and 100 µM) was inoculated with these PSB strains. Results showed that the bacteria increased the pH with a concomitant reduction in Al concentration, which translated into better rice growth. The improved root volume and seedling dry weight of the inoculated plants indicated the potential of these isolates to be used in a bio-fertilizer formulation for rice cultivation on acid sulfate soils.

Chemical and sensory characteristics of frozen wheygurt with the addition of taro and lesser yam flours as thickening agent

NASA Astrophysics Data System (ADS)

Nurhartadi, E.; Utami, R.; Widowati, E.; Karunawati, B. M.

2018-01-01

Cheese whey is a waste product from cheese processing. It has low solid contents thus required the addition of a thickening agent. Lactic acid bacteria could utilize it in the fermented drink. This research aims to study the effect of taro and lesser yam flour addition as a thickening agent on chemical and sensory characteristics of frozen wheygurt. This research used Complete Randomized Design (CRD) with one factor that is variation ratio of taro and lesser yam flour F1 (4: 0), F2 (3: 1), F3 (2: 2), F4 (1: 3), F5 (0: 4). The number of lactic acid bacteria cell determined by using hemocytometer. The lactic acid content determined by the titrimetric method by using 0.1 N NaOH and phenolphthalein as indicator. pH value measured with pH meter. Sensory characteristics evaluated using hedonic test. The result showed that the addition of taro and lesser yam flour have a significant effect on the number of lactic acid bacteria in frozen wheygurt. The higher lesser yam flour addition, the higher lactic acid bacteria count on frozen wheygurt, due to lesser yam higher glucose and fructo-oligosaccharide content than taro. The higher lesser yam addition, the higher the lactic acid produced. The higher the total bacteria and higher levels of lactic acid, the lower the pH obtained. The conclusion of this study is addition ratio of taro and lesser yam flour effect on the chemical characteristics of frozen wheygurt. There is no difference in the level of acceptance of the panelists in sensory evaluation.

Alteration of Rumen Bacteria and Protozoa Through Grazing Regime as a Tool to Enhance the Bioactive Fatty Acid Content of Bovine Milk

PubMed Central

Bainbridge, Melissa L.; Saldinger, Laurel K.; Barlow, John W.; Alvez, Juan P.; Roman, Joe; Kraft, Jana

2018-01-01

Rumen microorganisms are the origin of many bioactive fatty acids (FA) found in ruminant-derived food products. Differences in plant leaf anatomy and chemical composition between cool- and warm-season pastures may alter rumen microorganisms, potentially enhancing the quantity/profile of bioactive FA available for incorporation into milk. The objective of this study was to identify rumen bacteria and protozoa and their cellular FA when cows grazed a warm-season annual, pearl millet (PM), in comparison to a diverse cool-season pasture (CSP). Individual rumen digesta samples were obtained from five Holstein cows in a repeated measures design with 28-day periods. The treatment sequence was PM, CSP, then PM. Microbial DNA was extracted from rumen digesta and sequence reads were produced with Illumina MiSeq. Fatty acids (FA) were identified in rumen bacteria and protozoa using gas-liquid chromatography/mass spectroscopy. Microbial communities shifted in response to grazing regime. Bacteria of the phylum Bacteroidetes were more abundant during PM than CSP (P < 0.05), while protozoa of the genus Eudiplodinium were more abundant during CSP than PM (P < 0.05). Microbial cellular FA profiles differed between treatments. Bacteria and protozoa from cows grazing CSP contained more n-3 FA (P < 0.001) and vaccenic acid (P < 0.01), but lower proportions of branched-chain FA (P < 0.05). Microbial FA correlated with microbial taxa and levels of vaccenic acid, rumenic acid, and α-linolenic acid in milk. In conclusion, grazing regime can potentially be used to alter microbial communities shifting the FA profile of microbial cells, and subsequently, alter the milk FA profile. PMID:29867815

Alteration of Rumen Bacteria and Protozoa Through Grazing Regime as a Tool to Enhance the Bioactive Fatty Acid Content of Bovine Milk.

PubMed

Bainbridge, Melissa L; Saldinger, Laurel K; Barlow, John W; Alvez, Juan P; Roman, Joe; Kraft, Jana

2018-01-01

Rumen microorganisms are the origin of many bioactive fatty acids (FA) found in ruminant-derived food products. Differences in plant leaf anatomy and chemical composition between cool- and warm-season pastures may alter rumen microorganisms, potentially enhancing the quantity/profile of bioactive FA available for incorporation into milk. The objective of this study was to identify rumen bacteria and protozoa and their cellular FA when cows grazed a warm-season annual, pearl millet (PM), in comparison to a diverse cool-season pasture (CSP). Individual rumen digesta samples were obtained from five Holstein cows in a repeated measures design with 28-day periods. The treatment sequence was PM, CSP, then PM. Microbial DNA was extracted from rumen digesta and sequence reads were produced with Illumina MiSeq. Fatty acids (FA) were identified in rumen bacteria and protozoa using gas-liquid chromatography/mass spectroscopy. Microbial communities shifted in response to grazing regime. Bacteria of the phylum Bacteroidetes were more abundant during PM than CSP ( P < 0.05), while protozoa of the genus Eudiplodinium were more abundant during CSP than PM ( P < 0.05). Microbial cellular FA profiles differed between treatments. Bacteria and protozoa from cows grazing CSP contained more n-3 FA ( P < 0.001) and vaccenic acid ( P < 0.01), but lower proportions of branched-chain FA ( P < 0.05). Microbial FA correlated with microbial taxa and levels of vaccenic acid, rumenic acid, and α-linolenic acid in milk. In conclusion, grazing regime can potentially be used to alter microbial communities shifting the FA profile of microbial cells, and subsequently, alter the milk FA profile.

Biochemical and Molecular Characterization of Potential Phosphate-Solubilizing Bacteria in Acid Sulfate Soils and Their Beneficial Effects on Rice Growth

PubMed Central

Panhwar, Qurban Ali; Naher, Umme Aminun; Jusop, Shamshuddin; Othman, Radziah; Latif, Md Abdul; Ismail, Mohd Razi

2014-01-01

A study was conducted to determine the total microbial population, the occurrence of growth promoting bacteria and their beneficial traits in acid sulfate soils. The mechanisms by which the bacteria enhance rice seedlings grown under high Al and low pH stress were investigated. Soils and rice root samples were randomly collected from four sites in the study area (Kelantan, Malaysia). The topsoil pH and exchangeable Al ranged from 3.3 to 4.7 and 1.24 to 4.25 cmolc kg−1, respectively, which are considered unsuitable for rice production. Total bacterial and actinomycetes population in the acidic soils were found to be higher than fungal populations. A total of 21 phosphate-solubilizing bacteria (PSB) including 19 N2-fixing strains were isolated from the acid sulfate soil. Using 16S rRNA gene sequence analysis, three potential PSB strains based on their beneficial characteristics were identified (Burkholderia thailandensis, Sphingomonas pituitosa and Burkholderia seminalis). The isolated strains were capable of producing indoleacetic acid (IAA) and organic acids that were able to reduce Al availability via a chelation process. These PSB isolates solubilized P (43.65%) existing in the growth media within 72 hours of incubation. Seedling of rice variety, MR 219, grown at pH 4, and with different concentrations of Al (0, 50 and 100 µM) was inoculated with these PSB strains. Results showed that the bacteria increased the pH with a concomitant reduction in Al concentration, which translated into better rice growth. The improved root volume and seedling dry weight of the inoculated plants indicated the potential of these isolates to be used in a bio-fertilizer formulation for rice cultivation on acid sulfate soils. PMID:25285745

Differential sensitivity of polyhydroxyalkanoate producing bacteria to fermentation inhibitors and comparison of polyhydroxybutyrate production from Burkholderia cepacia and Pseudomonas pseudoflava.

PubMed

Dietrich, Diane; Illman, Barbara; Crooks, Casey

2013-06-04

The aim of this study is determine the relative sensitivity of a panel of seven polyhydroxyalkanoate producing bacteria to a panel of seven lignocellulosic-derived fermentation inhibitors representing aliphatic acids, furans and phenolics. A further aim was to measure the polyhydroxybutyrate production of select organisms on lignocellulosic-derived monosaccharides arabinose, xylose, glucose and mannose. We examined the sensitivity of seven polyhydroxyalkanoate producing bacteria: Azohydromonas lata, Bacillus megaterium, Bacillus cereus, Burkholderia cepacia, Pseudomonas olevorans, Pseudomonas pseudoflava and Ralstonia eutropha, against seven fermentation inhibitors produced by the saccharification of lignocellulose: acetic acid, levulinic acid, coumaric acid, ferulic acid, syringaldehyde, furfural, and hyroxymethyfurfural. There was significant variation in the sensitivity of these microbes to representative phenolics ranging from 0.25-1.5 g/L coumaric and ferulic acid and between 0.5-6.0 g/L syringaldehyde. Inhibition ranged from 0.37-4 g/L and 0.75-6 g/L with acetic acid and levulinic acid, respectively. B. cepacia and P. pseudoflava were selected for further analysis of polyhydroxyalkanoate production. We find significant differences in sensitivity to the fermentation inhibitors tested and find these variations to be over a relevant concentration range given the concentrations of inhibitors typically found in lignocellulosic hydrolysates. Of the seven bacteria tested, B. cepacia demonstrated the greatest inhibitor tolerance. Similarly, of two organisms examined for polyhydroxybutyrate production, B. cepacia was notably more efficient when fermenting pentose substrates.

Differential sensitivity of polyhydroxyalkanoate producing bacteria to fermentation inhibitors and comparison of polyhydroxybutyrate production from Burkholderia cepacia and Pseudomonas pseudoflava

PubMed Central

2013-01-01

Background The aim of this study is determine the relative sensitivity of a panel of seven polyhydroxyalkanoate producing bacteria to a panel of seven lignocellulosic-derived fermentation inhibitors representing aliphatic acids, furans and phenolics. A further aim was to measure the polyhydroxybutyrate production of select organisms on lignocellulosic-derived monosaccharides arabinose, xylose, glucose and mannose. Findings We examined the sensitivity of seven polyhydroxyalkanoate producing bacteria: Azohydromonas lata, Bacillus megaterium, Bacillus cereus, Burkholderia cepacia, Pseudomonas olevorans, Pseudomonas pseudoflava and Ralstonia eutropha, against seven fermentation inhibitors produced by the saccharification of lignocellulose: acetic acid, levulinic acid, coumaric acid, ferulic acid, syringaldehyde, furfural, and hyroxymethyfurfural. There was significant variation in the sensitivity of these microbes to representative phenolics ranging from 0.25-1.5 g/L coumaric and ferulic acid and between 0.5-6.0 g/L syringaldehyde. Inhibition ranged from 0.37-4 g/L and 0.75-6 g/L with acetic acid and levulinic acid, respectively. B. cepacia and P. pseudoflava were selected for further analysis of polyhydroxyalkanoate production. Conclusions We find significant differences in sensitivity to the fermentation inhibitors tested and find these variations to be over a relevant concentration range given the concentrations of inhibitors typically found in lignocellulosic hydrolysates. Of the seven bacteria tested, B. cepacia demonstrated the greatest inhibitor tolerance. Similarly, of two organisms examined for polyhydroxybutyrate production, B. cepacia was notably more efficient when fermenting pentose substrates. PMID:23734728

Fermentation characteristics and nutritive value of low moisture silage made from mature bermudagrass (C. dactylon) and switchgrass (P. virgatum) in mixture with alfalfa (M. sativa) or treated with urea and plantain (Musa AAB

USDA-ARS?s Scientific Manuscript database

Two experiments were conducted at the University of Kentucky Spindletop Farm in Lexington, Kentucky between October and November, 2009 to evaluate the effect of different percentages of alfalfa (Medicago sativa) as mixtures in switchgrass (Panicum virgatus) and bermudagrass (Cynodon dactylon) silage...

AAB and ABA Renewal as a Function of the Number of Extinction Trials in Conditioned Taste Aversion

ERIC Educational Resources Information Center

Rosas, Juan M.; Garcia-Gutierrez, Ana; Callejas-Aguilera, Jose E.

2007-01-01

Three experiments explored renewal in conditioned taste aversion after different amounts of extinction. In Experiment 1, three groups of rats received a single conditioning trial where a saccharin solution was paired with LiCl, followed by 3 extinction trials, and a two-trial test. Groups differed in the context where they received each of the…

The Effect of Contingent Reinforcement on Target Variables in Outpatient Psychotherapy for Depression: A Successful and Unsuccessful Case Using Functional Analytic Psychotherapy

ERIC Educational Resources Information Center

Kanter, Jonathan W.; Landes, Sara J.; Busch, Andrew M.; Rusch, Laura C.; Brown, Keri R.; Baruch, David E.; Holman, Gareth I.

2006-01-01

The current study investigated a behavior-analytic treatment, functional analytic psychotherapy (FAP), for outpatient depression utilizing two single-subject A/A+B designs. The baseline condition was cognitive behavioral therapy. Results demonstrated treatment success in 1 client after the addition of FAP and treatment failure in the 2nd. This…

In silico analysis of L-asparaginase from different source organisms.

PubMed

Dwivedi, Vivek Dhar; Mishra, Sarad Kumar

2014-06-01

L-asparaginases are widely distributed enzymes among plants, fungi and bacteria. This enzyme catalyzes the conversion of l-asparagine to l-aspartate and ammonia and to a lesser extent the formation of l-glutamate from l-glutamine. In the present study, forty-five full-length amino acid sequences of L-asparaginases from bacteria, fungi and plants were collected and subjected to multiple sequence alignment (MSA), domain identification, discovering individual amino acid composition, and phylogenetic tree construction. MSA revealed that two glycine residues were identically found in all analyzed species, two glycine residues were also identically found in all the fungal and bacterial sources and three glycine residues were identically found in all plant and bacterial sources while no residue was identically found in plant and fungal L-asparaginases. Two major sequence clusters were constructed by phylogenetic analysis. One cluster contains eleven species of fungi, twelve species of bacteria, and one species of plant, whereas the other one contains fourteen species of plant, four species of fungi and three species bacteria. The amino acid composition result revealed that the average frequency of amino acid alanine is 10.77 percent that is very high in comparison to other amino acids in all analyzed species.

Bacteriophages of lactic acid bacteria and their impact on milk fermentations

PubMed Central

2011-01-01

Every biotechnology process that relies on the use of bacteria to make a product or to overproduce a molecule may, at some time, struggle with the presence of virulent phages. For example, phages are the primary cause of fermentation failure in the milk transformation industry. This review focuses on the recent scientific advances in the field of lactic acid bacteria phage research. Three specific topics, namely, the sources of contamination, the detection methods and the control procedures will be discussed. PMID:21995802

Sensitive assay, based on hydroxy fatty acids from lipopolysaccharide lipid A, for Gram-negative bacteria in sediments.

PubMed Central

Parker, J H; Smith, G A; Fredrickson, H L; Vestal, J R; White, D C

1982-01-01

Biochemical measures have provided insight into the biomass and community structure of sedimentary microbiota without the requirement of selection by growth or quantitative removal from the sediment grains. This study used the assay of the hydroxy fatty acids released from the lipid A of the lipopolysaccharide in sediments to provide an estimate of the gram-negative bacteria. The method was sensitive to picomolar amounts of hydroxy fatty acids. The recovery of lipopolysaccharide hydroxy fatty acids from organisms added to sediments was quantitative. The lipids were extracted from the sediments with single-phase chloroform-methanol extraction. The lipid-extraction residue was hydrolyzed in 1 N HCl, and the hydroxy fatty acids of the lipopolysaccharide were recovered in chloroform for analysis by gas-liquid chromatography. This method proved to be about fivefold more sensitive than the classical phenol-water or trichloroacetic acid methods when applied to marine sediments. By examination of the patterns of hydroxy fatty acids, it was also possible to help define the community structure of the sedimentary gram-negative bacteria. PMID:6817712

Antimicrobial Activity and Chemical Composition of “Kpètè-Kpètè”: A Starter of Benin Traditional Beer Tchoukoutou

PubMed Central

N'tcha, Christine; Sina, Haziz; Kayodé, Adéchola Pierre Polycarpe; Gbenou, Joachim D.

2017-01-01

The aim of this study was to investigate the antibacterial effect of the crude starter “kpètè-kpètè” and lactic acid bacteria used during the production of “tchoukoutou.” To achieve this, a total of 11 lactic acid bacteria and 40 starter samples were collected from four communes. The samples were tested on 29 gram + and − strains by disk diffusion method. The minimum inhibitory and bactericidal concentrations of starter and lactic acid bacteria were determined by conventional methods. Organic acids, sugar, and volatile compounds were determined using the HPLC method. The “kpètè-kpètè” displays a high antibacterial activity against the tested strains. The most sensitive strain was S. epidermidis (12.5 mm) whereas the resistance strain was Proteus mirabilis (8 mm). All the tested ferment has not any inhibitory effect on Enterococcus faecalis. The lactic acid bacteria isolates of Parakou showed the highest (17.48 mm) antibacterial activity whereas the smallest diameter was obtained with the ferment collected from Boukoumbé (9.80 mm). The starters' chemical screening revealed the presence of tannins, anthocyanin flavonoids, triterpenes, steroids, reducing compounds, and mucilage O-glycosides. These compounds are probably the source of recorded inhibition effect. The lactic acid bacteria of the “kpètè-kpètè” could be used to develop a food ingredient with probiotic property. PMID:28367445

Extractive Fermentation of Lactic Acid in Lactic Acid Bacteria Cultivation: A Review.

PubMed

Othman, Majdiah; Ariff, Arbakariya B; Rios-Solis, Leonardo; Halim, Murni

2017-01-01

Lactic acid bacteria are industrially important microorganisms recognized for their fermentative ability mostly in their probiotic benefits as well as lactic acid production for various applications. Nevertheless, lactic acid fermentation often suffers end-product inhibition which decreases the cell growth rate. The inhibition of lactic acid is due to the solubility of the undissociated lactic acid within the cytoplasmic membrane and insolubility of dissociated lactate, which causes acidification of cytoplasm and failure of proton motive forces. This phenomenon influences the transmembrane pH gradient and decreases the amount of energy available for cell growth. In general, the restriction imposed by lactic acid on its fermentation can be avoided by extractive fermentation techniques, which can also be exploited for product recovery.

Extractive Fermentation of Lactic Acid in Lactic Acid Bacteria Cultivation: A Review

PubMed Central

Othman, Majdiah; Ariff, Arbakariya B.; Rios-Solis, Leonardo; Halim, Murni

2017-01-01

Lactic acid bacteria are industrially important microorganisms recognized for their fermentative ability mostly in their probiotic benefits as well as lactic acid production for various applications. Nevertheless, lactic acid fermentation often suffers end-product inhibition which decreases the cell growth rate. The inhibition of lactic acid is due to the solubility of the undissociated lactic acid within the cytoplasmic membrane and insolubility of dissociated lactate, which causes acidification of cytoplasm and failure of proton motive forces. This phenomenon influences the transmembrane pH gradient and decreases the amount of energy available for cell growth. In general, the restriction imposed by lactic acid on its fermentation can be avoided by extractive fermentation techniques, which can also be exploited for product recovery. PMID:29209295

Impact of succinate on growth of cultures of cecal bacteria from commercial broilers

USDA-ARS?s Scientific Manuscript database

Beneficial bacteria in probiotics produce and utilize several organic acids that may play a role in the ability of these bacteria to inhibit colonization of poultry by enteropathogens. Since cecal contents of adult poultry contain many of these beneficial bacteria, 3 experiments were conducted to ex...

Acetic Acid Bacteria and the Production and Quality of Wine Vinegar

PubMed Central

Torija, María Jesús; García-Parrilla, María del Carmen; Troncoso, Ana María

2014-01-01

The production of vinegar depends on an oxidation process that is mainly performed by acetic acid bacteria. Despite the different methods of vinegar production (more or less designated as either “fast” or “traditional”), the use of pure starter cultures remains far from being a reality. Uncontrolled mixed cultures are normally used, but this review proposes the use of controlled mixed cultures. The acetic acid bacteria species determine the quality of vinegar, although the final quality is a combined result of technological process, wood contact, and aging. This discussion centers on wine vinegar and evaluates the effects of these different processes on its chemical and sensory properties. PMID:24574887

Production of γ-aminobutyric acid by microorganisms from different food sources.

PubMed

Hudec, Jozef; Kobida, Ľubomír; Čanigová, Margita; Lacko-Bartošová, Magdaléna; Ložek, Otto; Chlebo, Peter; Mrázová, Jana; Ducsay, Ladislav; Bystrická, Judita

2015-04-01

γ-Aminobutyric acid (GABA) is a potentially bioactive component of foods and pharmaceuticals. The aim of this study was screen lactic acid bacteria belonging to the Czech Collection of Microorganisms, and microorganisms (yeast and bacteria) from 10 different food sources for GABA production by fermentation in broth or plant and animal products. Under an aerobic atmosphere, very low selectivity of GABA production (from 0.8% to 1.3%) was obtained using yeast and filamentous fungi, while higher selectivity (from 6.5% to 21.0%) was obtained with bacteria. The use of anaerobic conditions, combined with the addition of coenzyme (pyridoxal-5-phosphate) and salts (CaCl2 , NaCl), led to the detection of a low concentration of GABA precursor. Simultaneously, using an optimal temperature of 33 °C, a pH of 6.5 and bacteria from banana (Pseudomonadaceae and Enterobacteriaceae families), surprisingly, a high selectivity of GABA was obtained. A positive impact of fenugreek sprouts on the proteolytic process and GABA production from plant material as a source of GABA precursor was identified. Lactic acid bacteria for the production of new plant and animal GABA-rich products from different natural sources containing GABA precursor can be used. © 2014 Society of Chemical Industry.

Diversity of predominant lactic acid bacteria associated with cocoa fermentation in Nigeria.

PubMed

Kostinek, Melanie; Ban-Koffi, Louis; Ottah-Atikpo, Margaret; Teniola, David; Schillinger, Ulrich; Holzapfel, Wilhelm H; Franz, Charles M A P

2008-04-01

The fermentation of cocoa relies on a complex succession of bacteria and filamentous fungi, all of which can have an impact on cocoa flavor. So far, few investigations have focused on the diversity of lactic acid bacteria involved in cocoa fermentation, and many earlier investigations did not rely on polyphasic taxonomical approaches, which take both phenotypic and genotypic characterization techniques into account. In our study, we characterized predominant lactic acid bacteria from cocoa fermentations in Nigeria, using a combination of phenotypic tests, repetitive extragenic palindromic PCR, and sequencing of the 16S rRNA gene of representative strains for accurate species identification. Thus, of a total of 193 lactic acid bacteria (LAB) strains isolated from common media used to cultivate LAB, 40 (20.7%) were heterofermentative and consisted of either L. brevis or L. fermentum strains. The majority of the isolates were homofermentative rods (110 strains; 57% of isolates) which were characterized as L. plantarum strains. The homofermentative cocci consisted predominantly of 35 (18.1% of isolates) Pediococcus acidilactici strains. Thus, the LAB populations derived from these media in this study were accurately described. This can contribute to the further assessment of the effect of common LAB strains on the flavor characteristics of fermenting cocoa in further studies.

Acid and bile tolerance of spore-forming lactic acid bacteria.

PubMed

Hyronimus, B; Le Marrec, C; Sassi, A H; Deschamps, A

2000-11-01

Criteria for screening probiotics such as bile tolerance and resistance to acids were studied with 13 spore-forming lactic acid producing bacteria. Different strains of Sporolactobacillus, Bacillus laevolacticus, Bacillus racemilacticus and Bacillus coagulans grown in MRS broth were subjected to low pH conditions (2, 2.5 and 3) and increasing bile concentrations. Among these microorganisms, Bacillus laevolacticus DSM 6475 and all Sporolactobacillus strains tested except Sporolactobacillus racemicus IAM 12395, were resistant to pH 3. Only Bacillus racemilacticus and Bacillus coagulans strains were tolerant to bile concentrations over 0.3% (w/v).

ACUTE TOXICITY OF HEAVY METALS TO ACETATE-UTILIZING MIXED CULTURES OF SULFATE-REDUCING BACTERIA: EC100 AND EC50

EPA Science Inventory

Acid mine drainage (AMD) from abandoned mines and acid mine pitlakes is an important environmental contaminant concern and usually contains appreciable concentrations of heavy metals. Since sulfate-reducing bacteria (SRB) are involved in the treatment of AMD, knowledge of acute m...

Mine Waste Technology Program. In Situ Source Control Of Acid Generation Using Sulfate-Reducing Bacteria

EPA Science Inventory

This report summarizes the results of the Mine Waste Technology Program (MWTP) Activity III, Project 3, In Situ Source Control of Acid Generation Using Sulfate-Reducing Bacteria, funded by the U.S. Environmental Protection Agency (EPA) and jointly administered by EPA and the U.S....

Rapid quantification of live/dead lactic acid bacteria in probiotic products using high-sensitivity flow cytometry

NASA Astrophysics Data System (ADS)

He, Shengbin; Hong, Xinyi; Huang, Tianxun; Zhang, Wenqiang; Zhou, Yingxing; Wu, Lina; Yan, Xiaomei

2017-06-01

A laboratory-built high-sensitivity flow cytometer (HSFCM) was employed for the rapid and accurate detection of lactic acid bacteria (LAB) and their viability in probiotic products. LAB were stained with both the cell membrane-permeable SYTO 9 green-fluorescent nucleic acid stain and the red-fluorescent nucleic acid stain, propidium iodide, which penetrates only bacteria with compromised membranes. The side scatter and dual-color fluorescence signals of single bacteria were detected simultaneously by the HSFCM. Ultra-high temperature processing milk and skim milk spiked with Lactobacillus casei were used as the model systems for the optimization of sample pretreatment and staining. The viable LAB counts measured by the HSFCM were in good agreement with those of the plate count method, and the measured ratios between the live and dead LAB matched well with the theoretical ratios. The established method was successfully applied to the rapid quantification of live/dead LAB in yogurts and fermented milk beverages of different brands. Moreover, the concentration and viability status of LAB in ambient yogurt, a relatively new yet popular milk product in China, are also reported.

Antimicrobial Activity of Chlorhexidine, Peracetic acid/ Peroxide hydrogen and Alcohol based compound on Isolated Bacteria in Madani Heart Hospital, Tabriz, Azerbaijan, Iran

PubMed Central

Ghotaslou, Reza; Bahrami, Nashmil

2012-01-01

Purpose: The aim of present study was to investigate the effect of chemical agents on the clinical isolates in Madani Heart Hospital, Tabriz, Iran. Methods: The minimum bactericide concentration (MBC) of disinfectants including chlorhexidine (Fort), peracetic acid (Micro) and an alcohol based compound (Deconex) on selected bacteria at various dilutions were determined by the standard suspension technique. Results: MBC of Micro, Fort and Deconex were 2-128 mg/L, 2-64 mg/L and 4 - 32 mg/L, respectively. The Gram negative bacteria were more resistance to disinfectant relation to Gram positive bacteria. Conclusion: The results showed that these agents are able to eradicate the bacteria and they can be used lonely. PMID:24312771

Evaluation of sessile microorganisms in pipelines and cooling towers of some Iranian industries

NASA Astrophysics Data System (ADS)

Setareh, M.; Javaherdashti, R.

2006-02-01

Microbiologically influenced corrosion (MIC) is a kind of electrochemical corrosion that is enhanced by the effect of certain microorganisms including sessile bacteria. In this investigation, more than 200 samples collected from different systems of Iranian refineries have been examined (by culturing methods and observations) for corrosion-enhancing, biofilm-producing microorganisms such as sulfate-reducing bacteria (SRB), iron-oxidizing bacteria (IOB), heterotrophic biofilm-forming bacteria (HBB), and some eukaryotes such as fungi. This study showed the presence of microorganisms, such as SRB, HBB, thermophillic HBB, and yeasts, except for IOB. It was also revealed that biocides are used to reduce the number of planktonic (floating) bacteria, instead of the number of sessile bacteria, that form biofilms. Using surfactants, or washing with chemicals like chlorine or organic acids in overhauls, may destroy the biofilm and free the residential bacteria into the bulk solution, thus exposing them to the biocide. For thick biofilms, a chlorine or acid wash may also yield the same results.

The low photo-inactivation rate of bacteria in human plasma II. Inhibition of methylene blue bleaching in plasma and effective bacterial destruction by the addition of dilute acetic acid to human plasma.

PubMed

Chen, Jie; Cesario, Thomas C; Li, Runze; Er, Ali O; Rentzepis, Peter M

2015-10-01

Methylene blue (MB) and other photo-sensitizer molecules have been recognized as effective means for the inactivation of bacteria and other pathogens owing to their ability to photo-generate reactive oxygen species (ROS) including singlet oxygen. These reactive species react with the membrane of the bacteria causing their destruction. However, the efficiency of MB to destroy bacteria in plasma is very low because the MB 660 nm absorption band, that is responsible for the ROS generation, is bleached. The bleaching of MB, in plasma, is caused by the attachment of a hydrogen atom to the central ring nitrogen of MB, which destroys the ring conjugation and forms Leuco-MB which does not absorb in the 600 nm region. In this paper we show that addition of dilute acetic acid, ∼10(-4) M, to human plasma, prevents H-atom attachment to MB, allowing MB to absorb at 660 nm, generates singlet oxygen and thus inactivates bacteria. The mechanism proposed, for preventing MB bleaching in plasma, is based on the oxidation of cysteine to cystine, by reaction with added dilute acetic acid, thus eliminating the availability of the thiol hydrogen atom which attaches to the MB nitrogen. It is expected that the addition of acetic acid to plasma will be effective in the sterilization of plasma and killing of bacteria in wounds and burns.

Disordered nucleiome: Abundance of intrinsic disorder in the DNA- and RNA-binding proteins in 1121 species from Eukaryota, Bacteria and Archaea.

PubMed

Wang, Chen; Uversky, Vladimir N; Kurgan, Lukasz

2016-05-01

Intrinsically disordered proteins (IDPs) are abundant in various proteomes, where they play numerous important roles and complement biological activities of ordered proteins. Among functions assigned to IDPs are interactions with nucleic acids. However, often, such assignments are made based on the guilty-by-association principle. The validity of the extension of these correlations to all nucleic acid binding proteins has never been analyzed on a large scale across all domains of life. To fill this gap, we perform a comprehensive computational analysis of the abundance of intrinsic disorder and intrinsically disordered domains in nucleiomes (∼548 000 nucleic acid binding proteins) of 1121 species from Archaea, Bacteria and Eukaryota. Nucleiome is a whole complement of proteins involved in interactions with nucleic acids. We show that relative to other proteins in the corresponding proteomes, the DNA-binding proteins have significantly increased disorder content and are significantly enriched in disordered domains in Eukaryotes but not in Archaea and Bacteria. The RNA-binding proteins are significantly enriched in the disordered domains in Bacteria, Archaea and Eukaryota, while the overall abundance of disorder in these proteins is significantly increased in Bacteria, Archaea, animals and fungi. The high abundance of disorder in nucleiomes supports the notion that the nucleic acid binding proteins often require intrinsic disorder for their functions and regulation. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Bactericidal activities of GM flax seedcake extract on pathogenic bacteria clinical strains.

PubMed

Zuk, Magdalena; Dorotkiewicz-Jach, Agata; Drulis-Kawa, Zuzanna; Arendt, Malgorzata; Kulma, Anna; Szopa, Jan

2014-07-29

The antibiotic resistance of pathogenic microorganisms is a worldwide problem. Each year several million people across the world acquire infections with bacteria that are antibiotic-resistant, which is costly in terms of human health. New antibiotics are extremely needed to overcome the current resistance problem. Transgenic flax plants overproducing compounds from phenylpropanoid pathway accumulate phenolic derivatives of potential antioxidative, and thus, antimicrobial activity. Alkali hydrolyzed seedcake extract containing coumaric acid, ferulic acid, caffeic acid, and lignan in high quantities was used as an assayed against pathogenic bacteria (commonly used model organisms and clinical strains). It was shown that the extract components had antibacterial activity, which might be useful as a prophylactic against bacterial infection. Bacteria topoisomerase II (gyrase) inhibition and genomic DNA disintegration are suggested to be the main reason for rendering antibacterial action. The data obtained strongly suggest that the seedcake extract preparation is a suitable candidate for antimicrobial action with a broad spectrum and partial selectivity. Such preparation can be applied in cases where there is a risk of multibacterial infection and excellent answer on global increase in multidrug resistance in pathogenic bacteria.

Phenotypic and Genotypic Characterization of Some Lactic Acid Bacteria Isolated from Bee Pollen: A Preliminary Study

PubMed Central

BELHADJ, Hani; HARZALLAH, Daoud; BOUAMRA, Dalila; KHENNOUF, Seddik; Dahamna, Saliha; GHADBANE, Mouloud

2014-01-01

In the present work, five hundred and sixty-seven isolates of lactic acid bacteria were recovered from raw bee pollen grains. All isolates were screened for their antagonistic activity against both Gram-positive and Gram-negative pathogenic bacteria. Neutralized supernatants of 54 lactic acid bacteria (LAB) cultures from 216 active isolates inhibited the growth of indicator bacteria. They were phenotypically characterized, based on the fermentation of 39 carbohydrates. Using the simple matching coefficient and unweighted pair group algorithm with arithmetic averages (UPGMA), seven clusters with other two members were defined at the 79% similarity level. The following species were characterized: Lactobacillus plantarum, Lactobacillus fermentum, Lactococcus lactis, Pediococcus acidilactici, Pediococcus pentosaceus, and unidentified lactobacilli. Phenotypic characteristics of major and minor clusters were also identified. Partial sequencing of the 16S rRNA gene of representative isolates from each cluster was performed, and ten strains were assigned to seven species: Lactobacillus plantarum, Lactobacillus fermentum, Lactococcus lactis, Lactobacillus ingluviei, Pediococcus pentosaceus, Lactobacillus acidipiscis and Weissella cibaria. The molecular method used failed to determine the exact taxonomic status of BH0900 and AH3133. PMID:24936378

Phenotypic and genotypic characterization of some lactic Acid bacteria isolated from bee pollen: a preliminary study.

PubMed

Belhadj, Hani; Harzallah, Daoud; Bouamra, Dalila; Khennouf, Seddik; Dahamna, Saliha; Ghadbane, Mouloud

2014-01-01

In the present work, five hundred and sixty-seven isolates of lactic acid bacteria were recovered from raw bee pollen grains. All isolates were screened for their antagonistic activity against both Gram-positive and Gram-negative pathogenic bacteria. Neutralized supernatants of 54 lactic acid bacteria (LAB) cultures from 216 active isolates inhibited the growth of indicator bacteria. They were phenotypically characterized, based on the fermentation of 39 carbohydrates. Using the simple matching coefficient and unweighted pair group algorithm with arithmetic averages (UPGMA), seven clusters with other two members were defined at the 79% similarity level. The following species were characterized: Lactobacillus plantarum, Lactobacillus fermentum, Lactococcus lactis, Pediococcus acidilactici, Pediococcus pentosaceus, and unidentified lactobacilli. Phenotypic characteristics of major and minor clusters were also identified. Partial sequencing of the 16S rRNA gene of representative isolates from each cluster was performed, and ten strains were assigned to seven species: Lactobacillus plantarum, Lactobacillus fermentum, Lactococcus lactis, Lactobacillus ingluviei, Pediococcus pentosaceus, Lactobacillus acidipiscis and Weissella cibaria. The molecular method used failed to determine the exact taxonomic status of BH0900 and AH3133.

The determination and arrangement of a combination of enzyme lactate dehydrogenase of bacteria Acinetobacter sp. as a device the identity important bacteria agent composts

NASA Astrophysics Data System (ADS)

Sukmawati, D.; Puspitaningrum, R.; Muzajjanah

2017-07-01

The number of garbage generated by the industry or society is a usual problem encountered by almost all urban centers, especially large cities such as Jakarta. Waste prevention strategy required quickly and accurately. One strategy for tackling the Junk was getting lactic acid-producing bacteria. It has been shown that lactic acid can increase the acceleration of organic matter such as an overhaul of lignin and cellulose as well as out causing toxic compounds arising from decay. This research will be conducted on the determination and characterization of the enzyme-producing compost bacteria LDH lactate dehydrogenase LDH - which in isolation from the garbage Landfill Rawasari. Methodology: Research carried out consists: isolation of lactic acid-producing bacteria; identification of microscopic, macroscopic and staining Gram; cellulose assay, and optimization of PCR conditions LDH enzymes producing bacteria. Isolation is performed by dilution method and the direct method. As many as 5-point sampling. Each stage is conducted from 10 grams of soil from the top surface of the compost. Isolation results obtained 100 isolate the bacteria. Base on the characteristic of macroscopic and microscopic observations retrieved 14 isolates of bacteria have shaped rods and brought forth a negative kind of Gram positive staining. Bacterial isolates with codes (BK1; BK3; BK4; BK5; BK6; BK7; BK8; BK9; BK10; BK11: BK12; BK 13). The potential bacteria with ability produce lactate dehydrogenase was BK1 and BK3. Base for analysis phylogenetic there was identification bacteria bak1 and bak3 where Acinetobacter sp.

Amino Acid Analyses of Acid Hydrolysates in Desert Varnish

NASA Technical Reports Server (NTRS)

Perry, Randall S.; Staley, James T.; Dworkin, Jason P.; Engel, Mike

2001-01-01

There has long been a debate as to whether rock varnish deposits are microbially mediated or are deposited by inorganic processes. Varnished rocks are found throughout the world primarily in arid and semi-arid regions. The varnish coats are typically up to 200 microns thick and are composed of clays and alternating layers enriched in manganese and iron oxides. The individual layers range in thickness from 1 micron to greater than 10 microns and may continue laterally for more than a 100 microns. Overlapping botryoidal structures are visible in thin section and scanning electron micrographs. The coatings also include small amounts of organic mater and detrital grains. Amino-acid hydrolysates offer a means of assessing the organic composition of rock varnish collected from the Sonoran Desert, near Phoenix, AZ. Chromatographic analyses of hydrolysates from powdered samples of rock varnish suggest that the interior of rock varnish is relatively enriched in amino acids and specifically in d-alanine and glutamic acid. Peptidoglycan (murein) is the main structural component of gram-positive bacterial cell walls. The d-enantiomer of alanine and glutamic acid are specific to peptidoglycan and are consequently an indicator for the presence of bacteria. D-alanine is also found in teichoic acid which is only found in gram-positive bacteria. Several researchers have cultured bacteria from the surface of rock varnish and most have been gram-positive, suggesting that gram-positive bacteria are intimately associated with varnish coatings and may play a role in the formation of varnish coatings.

Activity and Stability of Biofilm Uricase of Lactobacillus plantarum for Uric Acid Biosensor

NASA Astrophysics Data System (ADS)

Iswantini, Dyah; Rachmatia, Rescy; Diana, Novita Rose; Nurhidayat, Novik; Akhiruddin; Saprudin, Deden

2016-01-01

Research of uric acid biosensor used a Lactobacillus plantarum was successfully conducted. Lactobacillus plantarum could produce uricase that could be used as uric acid biosensor. Therefore, lifetime of bacteria were quite short that caused the bacteria could not detect uric acid for a long time. To avoid this problem, development of biofilm for uric acid biosensor is important. Biofilms is a structured community of bacterial cells, stick together and are able to maintain a bacteria in an extreme environments. The purpose of present study was to determine and compare the activity of uricase produced by L. plantarum, deposited whithin biofilm and planktonic bacteria on glassy carbon electrode (GCEb & GCE), also to determine the stability of biofilm. The optimization process was conducted by using temperature, pH, and substrate concentration as the parameters. It showed that the activity of uricase within biofilm was able to increase the oxidation current. GCEb and GCE yielded the oxidation current in the amount of 47.24 μA and 23.04 μA, respectively, under the same condition. Results indicated that the optimum condition for uric acid biosensor using biofilm were pH 10, temperature of 40 oC, and uric acid concentration of 5 mM. The stability of GCEb decreased after 10 hours used, with decreasing percentage over 86.33%. This low stability probably caused by the unprotected active site of the enzyme that the enzyme is easier to experience the denaturation.

ON THE CLASSIFICATION OF THE STREPTOTHRICES, PARTICULARLY IN THEIR RELATION TO BACTERIA.

PubMed

Claypole, E J

1913-01-01

It is impossible from any point of view, morphological, biological or serological, to draw a sharp dividing line in this series. The forms change gradually from the mycelial organism to the bacillary, acid-fast organism. It is biologically a group complex and should be so considered. No doubt experiments with a larger series of species would yield results giving a possibility of closer classification and the introduction of some of the forms now in a debatable position, as Bacillus diphtheriae and Bacillus mallei, and other organisms, sometimes called, on account of their morphological irregularities, corynebacterium and mycobacterium, would help to show their real relation to both the Streptothrices and the true bacteria. The latter in many ways are acknowledged to be far from primitive; their endospores, flagella, and food habits all indicate a relatively high degree of specialization. Hence it would seem biologically more reasonable to look upon this group of Streptothrices with their variable morphology and close relationships as representing the ancestral type that gave rise to both the higher fungi and true bacteria, and not as being themselves higher bacteria. The various bacteria, other than the acid-fast forms, can readily have arisen from the non-acid-fast bacillary types, or even as non-acid-fast specializations of the mixed types. All the various forms shown at present by the bacteria,-cocci, spirilla, bacilli, etc.,-either separate or in chains and masses, are to be recognized in this group, and specializations in one or another line in the past would readily have given rise to the types we consider true bacteria. The processes of evolution have carried them far away from the parent stock and made them into this group. The recognition of this group complex and of the intermediate forms indicates clearly the past history and present relations of these interesting organisms. These relations may be represented by the following scheme. See PDF for Structure It is probable that the relation between the acid-fast organisms and the Streptothrices is a closer one than that between the Streptothrices and the bacteria, perhaps close enough to warrant a common genus for both.

Lactic acid bacteria isolated from soy sauce mash in Thailand.

PubMed

Tanasupawat, Somboon; Thongsanit, Jaruwan; Okada, Sanae; Komagata, Kazuo

2002-08-01

Fourteen sphere-shaped and 30 rod-shaped lactic acid bacteria were isolated from soy sauce mash of two factories in Thailand. These strains were separated into two groups, Group A and Group B, by cell shape and DNA-DNA similarity. Group A contained 14 tetrad-forming strains, and these strains were identified as Tetragenococcus halophilus by DNA similarity. Group B contained 30 rod-shaped bacteria, and they were further divided into four Subgroups, B1, B2, B3, and B4, and three ungrouped strains by phenotypic characteristics and DNA similarity. Subgroup B1 contained 16 strains, and these strains were identified as Lactobacillus acidipiscis by DNA similarity. Subgroup B2 included two strains, and the strains were identified as Lactobacillus farciminis by DNA similarity. Subgroup B3 contained five strains. The strains had meso-diaminopimelic acid in the cell wall, and were identified as Lactobacillus pentosus by DNA similarity. The strains tested produced DL-lactic acid from D-glucose. Subgroup B4 contained four strains. The strains had meso-diaminopimelic acid in the cell wall, and they were identified as Lactobacillus plantarum by DNA similarity. Two ungrouped strains were homofermentative, and one was heterofermentative. They showed a low degree of DNA similarity with the type strains tested, and were left unnamed. The distribution of lactic acid bacteria in soy sauce mash in Thailand is discussed.

Development and Application of Small-Subunit rRNA Probes for Assessment of Selected Thiobacillus Species and Members of the Genus Acidiphilium

PubMed Central

Peccia, Jordan; Marchand, Eric A.; Silverstein, Joann; Hernandez, Mark

2000-01-01

Culture-dependent studies have implicated sulfur-oxidizing bacteria as the causative agents of acid mine drainage and concrete corrosion in sewers. Thiobacillus species are considered the major representatives of the acid-producing bacteria in these environments. Small-subunit rRNA genes from all of the Thiobacillus and Acidiphilium species catalogued by the Ribosomal Database Project were identified and used to design oligonucleotide DNA probes. Two oligonucleotide probes were synthesized to complement variable regions of 16S rRNA in the following acidophilic bacteria: Thiobacillus ferrooxidans and T. thiooxidans (probe Thio820) and members of the genus Acidiphilium (probe Acdp821). Using 32P radiolabels, probe specificity was characterized by hybridization dissociation temperature (Td) with membrane-immobilized RNA extracted from a suite of 21 strains representing three groups of bacteria. Fluorochrome-conjugated probes were evaluated for use with fluorescent in situ hybridization (FISH) at the experimentally determined Tds. FISH was used to identify and enumerate bacteria in laboratory reactors and environmental samples. Probing of laboratory reactors inoculated with a mixed culture of acidophilic bacteria validated the ability of the oligonucleotide probes to track specific cell numbers with time. Additionally, probing of sediments from an active acid mine drainage site in Colorado demonstrated the ability to identify numbers of active bacteria in natural environments that contain high concentrations of metals, associated precipitates, and other mineral debris. PMID:10877807

SERDP CU-1129 Biological Assessment for Characterizing Contamination Risk at the Genetic-, Individual-, and Population-Level

DTIC Science & Technology

2004-04-14

albimanus Quetzal : a Tc1 transposon (Sum P(2) = 8.3e-07) Transposase_5, E = 5.9e-08 Topo 6-2L3 LpTc1.1 A. albimanus Quetzal : a Tc1 transposon (Sum P(2...transposon LpTc1, A. albimanus Quetzal = Anopheles albimanus Quetzal transposase (AAB02109). The clones tank and tank.1 did not have sufficient

Antisocial behavioral syndromes and return to drug use following residential relapse prevention/health education treatment.

PubMed

Goldstein, R B; Bigelow, C; McCusker, J; Lewis, B F; Mundt, K A; Powers, S I

2001-08-01

This study compared residential addiction treatment clients meeting full DSM-III-R criteria for antisocial personality disorder (ASPD) with those reporting syndromal levels of antisocial behavior only in adulthood (AABS) on time to and severity of first posttreatment drug use. Antisocial syndrome and selected other mental disorders were assessed using the Diagnostic Interview Schedule, Revised for DSM-III-R, and validity of self-reported posttreatment drug behavior was measured against results of hair analysis. Among subjects followed within 180 days after treatment exit, individuals with ASPD were at modestly increased risk of a first lapse episode compared to those with AABS. However, the two groups did not differ in severity of lapse. Participants with ASPD demonstrated poorer agreement between self-reported posttreatment drug behavior and hair data. These results add to the evidence suggesting that the DSM requirement for childhood onset in ASPD may be clinically important among substance abusers in identifying a severely antisocial and chronically addicted group at elevated risk for early posttreatment recidivism. Our findings support the importance of careful classification of antisocial syndromes among substance abusers and the identification of characteristics of these syndromes that underlie clients' risks for posttreatment return to drug use to provide optimally individualized treatment planning.

Isotopic Randomness and Maxwell's Demon

NASA Astrophysics Data System (ADS)

Berezin, Alexander A.

2005-03-01

Isotopic disorder in crystals can lead to suppression of thermal conductivity, mobility variations and (weak) Anderson localization on isotopic fluctuations. The latter (AAB, J.ChemPhys.1984) is akin to polaron effect (self-localization due polarization). Possibility of isotopic patterning (IP) increases near melting point (thermally activated isotopic hopping swaps). Crystal near melting threshold become “informationally sensitive” as if its IP is operated by some external Maxwell’s Demon, MD (AAB, URAM J, 2002). At this state short range (e.g. electrostatic inverse square) forces evolve into long-range interactions (due to divergence of order parameter) and information sensitivity can be further amplified by (say) a single fast electron (e.g. beta-particle from decay of 14-C or other radioactive isotope) which may result in cascade of impact ionization events and (short time-scale) enhancement of screening by impact-generated non-equilibrium (non-thermal) electrons. In this state informationally driven (MD-controlled) IP (Eccles effect) can result in decrease of positional entropy signifying emergence of physical complexity out of pure information, similar to peculiar “jinni effect” on closed time loops in relativistic cosmology (R.J.Gott, 2001) or Wheeler’s “it from bit” metaphor. By selecting special IP, MD modifies ergodicity principle in favor of info rich states.

Probiotic potential of noni juice fermented with lactic acid bacteria and bifidobacteria.

PubMed

Wang, Chung-Yi; Ng, Chang-Chai; Su, Hsuan; Tzeng, Wen-Sheng; Shyu, Yuan-Tay

2009-01-01

The present study assesses the feasibility of noni as a raw substrate for the production of probiotic noni juice by lactic acid bacteria (Lactobacilluscasei and Lactobacillus plantarum) and bifidobacteria (Bifidobacteriumlongum). Changes in pH, acidity, sugar content, cell survival and antioxidant properties during fermentation were monitored. All tested strains grew well on noni juice, reaching nearly 10⁹ colony-forming units/ml after 48 h fermentation. L.casei produced less lactic acid than B.longum and L. plantarum. After 4 weeks of cold storage at 4°C, B.longum and L. plantarum survived under low-pH conditions in fermented noni juice. In contrast, L.casei exhibited no cell viability after 3 weeks. Moreover, noni juice fermented with B.longum had a high antioxidant capacity that did not differ significantly (P <0.05) from that of lactic acid bacteria. Finally, we found that B.longum and L. plantarum are optimal probiotics for fermentation with noni juice.

In vitro quantitative analysis of Salmonella typhimurium preference for amino acids secreted by human breast tumor

NASA Astrophysics Data System (ADS)

Choi, Eunpyo; Maeng, Bohee; Lee, Jae-hun; Chang, Hyung-kwan; Park, Jungyul

2016-12-01

Bacterial therapies have been paid significant attentions by their ability to penetrate deep into the solid tumor tissue and its propensity to naturally accumulate in tumors of living animals. Understanding the actual mechanism for bacteria to target the tumor is therapeutically crucial but is poorly understood. We hypothesized that amino acids released from the specific tumors induced bacteria to those tumors and the experiments for chemotactic response of bacteria toward the cancer secreting amino acids was then performed by using the diffusion based multiple chemical gradient generator constructed by in situ self-assembly of microspheres. The quantitative analysis was carried out by comparison of intensity using green fluorescent protein (GFP) tagged Salmonella typhimurium ( S. typhimurium) in the gradient generator, which showed the clear preference to the released amino acids, especially from breast cancer patients. The understanding chemotaxis toward the cancer secreting amino acids is essential for controlling S. typhimurium targeting in tumors and will allow for the development of bacterial therapies.

Extracellular nucleic acids of the marine bacterium Rhodovulum sulfidophilum and recombinant RNA production technology using bacteria.

PubMed

Kikuchi, Yo; Umekage, So

2018-02-01

Extracellular nucleic acids of high molecular weight are detected ubiquitously in seawater. Recent studies have indicated that these nucleic acids are, at least in part, derived from active production by some bacteria. The marine bacterium Rhodovulum sulfidophilum is one of those bacteria. Rhodovulumsulfidophilum is a non-sulfur phototrophic marine bacterium that is known to form structured communities of cells called flocs, and to produce extracellular nucleic acids in culture media. Recently, it has been revealed that this bacterium produces gene transfer agent-like particles and that this particle production may be related to the extracellular nucleic acid production mechanism. This review provides a summary of recent physiological and genetic studies of these phenomena and also introduces a new method for extracellular production of artificial and biologically functional RNAs using this bacterium. In addition, artificial RNA production using Escherichia coli, which is related to this topic, will also be described. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Ice-Nucleating Bacteria

NASA Astrophysics Data System (ADS)

Obata, Hitoshi

Since the discovery of ice-nucleating bacteria in 1974 by Maki et al., a large number of studies on the biological characteristics, ice-nucleating substance, ice nucleation gene and frost damage etc. of the bacteria have been carried out. Ice-nucleating bacteria can cause the freezing of water at relatively warm temperature (-2.3°C). Tween 20 was good substrates for ice-nucleating activity of Pseudomonas fluorescens KUIN-1. Major fatty acids of Isolate (Pseudomonas fluorescens) W-11 grown at 30°C were palmitic, cis-9-hexadecenoic and cis-11-octadecenoic which amounted to 90% of the total fatty acids. Sequence analysis shows that an ice nucleation gene from Pseudomonas fluorescens is related to the gene of Pseudomonas syringae.

Kullback Leibler divergence in complete bacterial and phage genomes

PubMed Central

Akhter, Sajia; Kashef, Mona T.; Ibrahim, Eslam S.; Bailey, Barbara

2017-01-01

The amino acid content of the proteins encoded by a genome may predict the coding potential of that genome and may reflect lifestyle restrictions of the organism. Here, we calculated the Kullback–Leibler divergence from the mean amino acid content as a metric to compare the amino acid composition for a large set of bacterial and phage genome sequences. Using these data, we demonstrate that (i) there is a significant difference between amino acid utilization in different phylogenetic groups of bacteria and phages; (ii) many of the bacteria with the most skewed amino acid utilization profiles, or the bacteria that host phages with the most skewed profiles, are endosymbionts or parasites; (iii) the skews in the distribution are not restricted to certain metabolic processes but are common across all bacterial genomic subsystems; (iv) amino acid utilization profiles strongly correlate with GC content in bacterial genomes but very weakly correlate with the G+C percent in phage genomes. These findings might be exploited to distinguish coding from non-coding sequences in large data sets, such as metagenomic sequence libraries, to help in prioritizing subsequent analyses. PMID:29204318

Kullback Leibler divergence in complete bacterial and phage genomes.

PubMed

Akhter, Sajia; Aziz, Ramy K; Kashef, Mona T; Ibrahim, Eslam S; Bailey, Barbara; Edwards, Robert A

2017-01-01

The amino acid content of the proteins encoded by a genome may predict the coding potential of that genome and may reflect lifestyle restrictions of the organism. Here, we calculated the Kullback-Leibler divergence from the mean amino acid content as a metric to compare the amino acid composition for a large set of bacterial and phage genome sequences. Using these data, we demonstrate that (i) there is a significant difference between amino acid utilization in different phylogenetic groups of bacteria and phages; (ii) many of the bacteria with the most skewed amino acid utilization profiles, or the bacteria that host phages with the most skewed profiles, are endosymbionts or parasites; (iii) the skews in the distribution are not restricted to certain metabolic processes but are common across all bacterial genomic subsystems; (iv) amino acid utilization profiles strongly correlate with GC content in bacterial genomes but very weakly correlate with the G+C percent in phage genomes. These findings might be exploited to distinguish coding from non-coding sequences in large data sets, such as metagenomic sequence libraries, to help in prioritizing subsequent analyses.

Effects of growth stage and fulvic acid on the diversity and dynamics of endophytic bacterial community in Stevia rebaudiana Bertoni leaves

PubMed Central

Yu, Xuejian; Yang, Jinshui; Wang, Entao; Li, Baozhen; Yuan, Hongli

2015-01-01

The aim of this study was to learn the interactions among the endophytic bacteria, the plant growth, the foliar spray of fulvic acid, and the accumulation of steviol glycosides in the leaves of Stevia rebaudiana. Metagenomic DNA was extracted from the Stevia leaves at different growth stages with or without the fulvic acid treatment; and the diversity of endophytic bacteria in Stevia leaves was estimated by pyrosequencing of 16S rRNA genes. As results, Proteobacteria, Actinobacteria, Bacteroidetes, and Firmicutes were found to be the dominant phyla despite the growth stages and fulvic acid application. Stevia growth stages strongly regulated composition of endophytic community. The genera Agrobacterium (12.3%) and Erwinia (7.2%) dominated in seedling stage were apparently declined in the vegetable and initial flowering stages, while Sphingomonas and Methylobacterium increased in mature leaves at harvest time, which showed that the mature leaves of Stevia preferred to accumulate some certain endophytic bacteria. Sphingomonas and Methylobacterium constituted an important part of the core endophytic community and were positively correlated with the stevioside content and UGT74G1 gene expression, respectively; while Erwinia, Agrobacterium, and Bacillus were negatively correlated with the stevioside accumulation. Fulvic acid treatment accelerated the variation of endophytes along the growth stages and increased the steviol glycosides content. This is the first study to reveal the community composition of endophytic bacteria in the Stevia leaves, to evidence the strong effects of growth stage and fulvic acid application on the endophytes of Stevia, and to demonstrate the correlation between the endophytic bacteria and the steviol glycosides accumulation. PMID:26379644

Effect of various antibiotics on modulation of intestinal microbiota and bile acid profile in mice

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

Zhang, Youcai; Limaye, Pallavi B.; Renaud, Helen J.

Antibiotic treatments have been used to modulate intestinal bacteria and investigate the role of intestinal bacteria on bile acid (BA) homeostasis. However, knowledge on which intestinal bacteria and bile acids are modified by antibiotics is limited. In the present study, mice were administered various antibiotics, 47 of the most abundant bacterial species in intestine, as well as individual BAs in plasma, liver, and intestine were quantified. Compared to the two antibiotic combinations (vancomycin + imipenem and cephalothin + neomycin), the three single antibiotics (metronidazole, ciprofloxacin and aztreonam) have less effect on intestinal bacterial profiles, and thus on host BA profilesmore » and mRNA expression of genes that are important for BA homeostasis. The two antibiotic combinations decreased the ratio of Firmicutes to Bacteroidetes in intestine, as well as most secondary BAs in serum, liver and intestine. Additionally, the two antibiotic combinations significantly increased mRNA of the hepatic BA uptake transporters (Ntcp and Oatp1b2) and canalicular BA efflux transporters (Bsep and Mrp2), but decreased mRNA of the hepatic BA synthetic enzyme Cyp8b1, suggesting an elevated enterohepatic circulation of BAs. Interestingly, the two antibiotic combinations tended to have opposite effect on the mRNAs of most intestinal genes, which tended to be inhibited by vancomycin + imipenem but stimulated by cephalothin + neomycin. To conclude, the present study clearly shows that various antibiotics have distinct effects on modulating intestinal bacteria and host BA metabolism. - Highlights: • Various antibiotics have different effects on intestinal bacteria. • Antibiotics alter bile acid composition in mouse liver and intestine. • Antibiotics influence genes involved in bile acid homeostasis. • Clostridia appear to be important for secondary bile acid formation.« less

Production and transformation of dissolved neutral sugars and amino acids by bacteria in seawater

NASA Astrophysics Data System (ADS)

Jørgensen, L.; Lechtenfeld, O. J.; Benner, R.; Middelboe, M.; Stedmon, C. A.

2014-10-01

Dissolved organic matter (DOM) in the ocean consists of a heterogeneous mixture of molecules, most of which are of unknown origin. Neutral sugars and amino acids are among the few recognizable biomolecules in DOM, and the molecular composition of these biomolecules is shaped primarily by biological production and degradation processes. This study provides insight into the bioavailability of biomolecules as well as the chemical composition of DOM produced by bacteria. The molecular compositions of combined neutral sugars and amino acids were investigated in DOM produced by bacteria and in DOM remaining after 32 days of bacterial degradation. Results from bioassay incubations with natural seawater (sampled from water masses originating from the surface waters of the Arctic Ocean and the North Atlantic Ocean) and artificial seawater indicate that the molecular compositions following bacterial degradation are not strongly influenced by the initial substrate or bacterial community. The molecular composition of neutral sugars released by bacteria was characterized by a high glucose content (47 mol %) and heterogeneous contributions from other neutral sugars (3-14 mol %). DOM remaining after bacterial degradation was characterized by a high galactose content (33 mol %), followed by glucose (22 mol %) and the remaining neutral sugars (7-11 mol %). The ratio of D-amino acids to L-amino acids increased during the experiments as a response to bacterial degradation, and after 32 days, the D/L ratios of aspartic acid, glutamic acid, serine and alanine reached around 0.79, 0.32, 0.30 and 0.51 in all treatments, respectively. The striking similarity in neutral sugar and amino acid compositions between natural (representing marine semi-labile and refractory DOM) and artificial (representing bacterially produced DOM) seawater samples, suggests that microbes transform bioavailable neutral sugars and amino acids into a common, more persistent form.

BIOAVAILABILITY AND TROPHIC TRANSFER OF HUMIC-BOUND COPPER FROM BACTERIA TO ZOOPLANKTON

EPA Science Inventory

The effect of humic acid (HA) on uptake and transfer of Cu by selected marine organisms from the microbial loop was determined. Bacteria grown to stationary phase in cultures with and without 15 ug Cu l -1 and with and without 10 mg Suwannee River Humic Acid (SRHA) l -1 were fed ...

Characterization of nitrate-reducing and amino acid-using bacteria prominent in nitrotoxin-enriched equine cecal populations

USDA-ARS?s Scientific Manuscript database

In the present study, populations of equine cecal microbes enriched for enhanced rates of 3-nitro-1-propionic acid (NPA) or nitrate metabolism were diluted and cultured for NPA-metabolizing bacteria on a basal enrichment medium (BEM) or tryptose soy agar (TSA) medium supplemented with either 5 mM NP...

Bacteria and Archaea in acidic environments and a key to morphological identification

USGS Publications Warehouse

Robbins, E.I.

2000-01-01

Natural and anthropogenic acidic environments are dominated by bacteria and Archaea. As many as 86 genera or species have been identified or isolated from pH <4.5 environments. This paper reviews the worldwide literature and provide tables of morphological characteristics, habitat information and a key for light microscope identification for the non-microbiologist.

Preliminary tests on nisin and pediocin production using waste protein sources. Factorial and kinetic studies.

PubMed

Vázquez, J A; González, M P; Murado, M A

2006-03-01

Lactic acid bacteria, the object of current interest as bacteriocin producers, are microorganisms with complex requirements for peptidic sources, making them appropriate indicators for testing the suitability of formulations based on proteinaceous wastes for use as microbiological media. Different peptones obtained from visceral and fish muscle residues promoted growth of lactic acid bacteria when applied individually or in combination. Kinetic parameters and bacteriocin production were similar and, in some cases (pediocin), far superior (>500%) to those obtained with bactopeptones and commercial media specifically recommended for lactic acid bacteria growth. Visceral residues, especially when subjected to a brief process of autohydrolysis at 20 degrees C, were more efficient for bacterial growth than muscle, even when muscle was treated with pepsin.

Use of an acidophilic yeast strain to enable the growth of leaching bacteria on solid media.

PubMed

Ngom, Baba; Liang, Yili; Liu, Yi; Yin, Huaqun; Liu, Xueduan

2015-03-01

In this study, a Candida digboiensis strain was isolated from a heap leaching plant in Zambia and used in double-layer agar plate to efficiently isolate and purify leaching bacteria. Unlike Acidiphilium sp., the yeast strain was tetrathionate tolerant and could metabolize a great range of organic compounds including organic acids. These properties allowed the yeast strain to enable and fasten the growth of iron and sulfur oxidizers on double-layer agar plate. The isolates were identified as Acidithiobacillus ferrooxidans FOX1, Leptospirillun ferriphilum BN, and Acidithiobacillus thiooxidans ZMB. These three leaching bacteria were inhibited by organic acids such as acetic and propionic acids; however, their activities were enhanced by Candida digboiensis NB under dissolved organic matter stress.

Beer spoilage bacteria and hop resistance.

PubMed

Sakamoto, Kanta; Konings, Wil N

2003-12-31

For brewing industry, beer spoilage bacteria have been problematic for centuries. They include some lactic acid bacteria such as Lactobacillus brevis, Lactobacillus lindneri and Pediococcus damnosus, and some Gram-negative bacteria such as Pectinatus cerevisiiphilus, Pectinatus frisingensis and Megasphaera cerevisiae. They can spoil beer by turbidity, acidity and the production of unfavorable smell such as diacetyl or hydrogen sulfide. For the microbiological control, many advanced biotechnological techniques such as immunoassay and polymerase chain reaction (PCR) have been applied in place of the conventional and time-consuming method of incubation on culture media. Subsequently, a method is needed to determine whether the detected bacterium is capable of growing in beer or not. In lactic acid bacteria, hop resistance is crucial for their ability to grow in beer. Hop compounds, mainly iso-alpha-acids in beer, have antibacterial activity against Gram-positive bacteria. They act as ionophores which dissipate the pH gradient across the cytoplasmic membrane and reduce the proton motive force (pmf). Consequently, the pmf-dependent nutrient uptake is hampered, resulting in cell death. The hop-resistance mechanisms in lactic acid bacteria have been investigated. HorA was found to excrete hop compounds in an ATP-dependent manner from the cell membrane to outer medium. Additionally, increased proton pumping by the membrane bound H(+)-ATPase contributes to hop resistance. To energize such ATP-dependent transporters hop-resistant cells contain larger ATP pools than hop-sensitive cells. Furthermore, a pmf-dependent hop transporter was recently presented. Understanding the hop-resistance mechanisms has enabled the development of rapid methods to discriminate beer spoilage strains from nonspoilers. The horA-PCR method has been applied for bacterial control in breweries. Also, a discrimination method was developed based on ATP pool measurement in lactobacillus cells. However, some potential hop-resistant strains cannot grow in beer unless they have first been exposed to subinhibitory concentration of hop compounds. The beer spoilage ability of Pectinatus spp. and M. cerevisiae has been poorly studied. Since all the strains have been reported to be capable of beer spoiling, species identification is sufficient for the breweries. However, with the current trend of beer flavor (lower alcohol and bitterness), there is the potential risk that not yet reported bacteria will contribute to beer spoilage. Investigation of the beer spoilage ability of especially Gram-negative bacteria may be useful to reduce this risk.

Antimicrobial activity of Schinus lentiscifolius (Anacardiaceae).

PubMed

Gehrke, Ilaine T S; Neto, Alexandre T; Pedroso, Marcelo; Mostardeiro, Clarice P; Da Cruz, Ivana B M; Silva, Ubiratan F; Ilha, Vinicius; Dalcol, Ionara I; Morel, Ademir F

2013-07-09

Schinus lentiscifolius Marchand (syn. Schinus weinmannifolius Engl) is a plant native to Rio Grande do Sul (Southern Brazil) and has been used in Brazilian traditional medicine as antiseptic and antimicrobial for the treatment of many different health problems as well as to treat leucorrhea and to assist in ulcer and wound healing. Although it is a plant widely used by the population, there are no studies proving this popular use. The crude aqueous extract, the crude neutral methanol extract, fractions prepared from this extract (n-hexane, ethyl acetate, and n-butanol), pure compounds isolated from these fractions, and derivatives were investigated in vitro for antimicrobial activities against five Gram positive bacteria: Bacillus subtilis, Staphylococcus aureus, Staphylococcus epidermidis, Staphylococcus saprophyticus, Streptococcus pyogenes, three Gram negative bacteria: Escherichia coli, Pseudomonas aeruginosa, and Shigella sonnei, and four yeasts: Candida albicans, Candida tropicalis, Cryptococcus neoformans, and Saccharomyces cerevisiae. The isolated compound moronic acid, which is the most active, was tested against a range of other bacteria such as two Gram positive bacteria, namely, Bacillus cereus, Enterococcus spp, and six Gram negative bacteria, namely, Burkholderia cepacia, Providencia stuartii, Morganella morganii, Enterobacter cloacae, Enterobacter aerogenes, and Proteus mirabilis. The leaf aqueous extract (decoction) of Schinus lentiscifolius showed a broad spectrum of antibacterial activity, ranging from 125 to 250 μg/ml (MIC) against the tested bacteria and fungi. The n-hexane extract, despite being very little active against bacteria, showed an excellent antifungal activity, especially against Candida albicans (MIC=25 μg/ml), Candida tropicalis (MIC=15.5 μg/ml), and Cryptococcus neoformans, (MIC=15.5 μg/ml). From the acetate fraction (the most active against bacteria), compounds 1-6 were isolated: nonadecanol (1), moronic acid (2), gallic acid methyl ester (3), gallic acid (4), quercetin (5) and quercitrin (6). The minimal inhibitory concentration (MIC) of moronic acid between 1.5 and 3 μg/ml against most of the tested bacteria shows that it is one of the metabolites responsible for the antibacterial activity of Schinus lentiscifolius. The antimicrobial activity and some constituents of Schinus lentiscifolius are reported for the first time. The results of the present study provide scientific basis for the popular use of Schinus lentiscifolius for a number of different health problems. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Characterization of Lactic Acid Bacteria (LAB) isolated from Indonesian shrimp paste (terasi)

NASA Astrophysics Data System (ADS)

Amalia, U.; Sumardianto; Agustini, T. W.

2018-02-01

Shrimp paste was one of fermented products, popular as a taste enhancer in many dishes. The processing of shrimp paste was natural fermentation, depends on shrimp it self and the presence of salt. The salt inhibits the growth of undesirable microorganism and allows the salt-tolerant lactic acid bacteria (LAB) to ferment the protein source to lactic acids. The objectives of this study were to characterize LAB isolated from Indonesian shrimp paste or "Terasi" with different times of fermentation (30, 60 and 90 days). Vitech analysis showed that there were four strains of the microorganism referred to as lactic acid bacteria (named: LABS1, LABS2, LABS3 and LABS4) with 95% sequence similarity. On the basis of biochemical, four isolates represented Lactobacillus, which the name Lactobacillus plantarum is proposed. L.plantarum was play role in resulting secondary metabolites, which gave umami flavor in shrimp paste.

Relation between chemotaxis and consumption of amino acids in bacteria

PubMed Central

Yang, Yiling; M. Pollard, Abiola; Höfler, Carolin; Poschet, Gernot; Wirtz, Markus; Hell, Rüdiger

2015-01-01

Summary Chemotaxis enables bacteria to navigate chemical gradients in their environment, accumulating toward high concentrations of attractants and avoiding high concentrations of repellents. Although finding nutrients is likely to be an important function of bacterial chemotaxis, not all characterized attractants are nutrients. Moreover, even for potential nutrients, the exact relation between the metabolic value of chemicals and their efficiency as chemoattractants has not been systematically explored. Here we compare the chemotactic response of amino acids with their use by bacteria for two well‐established models of chemotactic behavior, E scherichia coli and B acillus subtilis. We demonstrate that in E . coli chemotaxis toward amino acids indeed strongly correlates with their utilization. However, no such correlation is observed for B . subtilis, suggesting that in this case, the amino acids are not followed because of their nutritional value but rather as environmental cues. PMID:25807888

Bacillus subtilis UBTn7, a potential producer of L - Methioninase isolated from mangrove, Rhizophora mucronata

NASA Astrophysics Data System (ADS)

Prihanto, A. A.

2018-04-01

L-methioninase is an enzyme that degrades sulfur-containing amino acids to α-keto acids, ammonia, and thiols. L-methioninase could be found in plants, bacteria, and fungi. The aims of this study was to obtain L-methioninase-producing endophytic bacteria isolated from mangrove Rhizophora mucronata. The mangrove was collected from Jenu Beach, Tuban, East Java, Indonesia. The samples were roots, stems, and leaves of Rhizophora mucronata. Endophytic bacteria were pure isolated using LB agar medium. Each bacteria were screened its capability to produce L-methioninase using selective media namely modified Czapek Dox agar. The best producer of enzyme was further identified with morphological and biochemical analysis. The result showed that three bacteria produced L-methioninase. Based on the result of morphological and biochemical analysis, the best producer was Bacillus subtilis UBTn7.

Time series analysis of aerobic bacterial flora during Miso fermentation.

PubMed

Onda, T; Yanagida, F; Tsuji, M; Shinohara, T; Yokotsuka, K

2003-01-01

This article reports a microbiological study of aerobic mesophilic bacteria that are present during the fermentation process of Miso. Aerobic bacteria were enumerated and isolated from Miso during fermentation and divided into nine groups using traditional phenotypic tests. The strains were identified by biochemical analysis and 16S rRNA sequence analysis. They were identified as Bacillus subtilis, B. amyloliquefaciens, Kocuria kristinae, Staphylococcus gallinarum and S. kloosii. All strains were sensitive to the bacteriocins produced by the lactic acid bacteria isolated from Miso. The dominant species among the undesirable species throughout the fermentation process were B. subtilis and B. amyloliquefaciens. It is suggested that bacteriocin-producing lactic acid bacteria are effective in the growth prevention of aerobic bacteria in Miso. This study has provided useful information for controlling of bacterial flora during Miso fermentation.

Chemical characteristic of salt fermented meat inoculated with Pediococcus ssp

NASA Astrophysics Data System (ADS)

Pramono, Y. B.; Rahayu, E. S.; Suparmo; Utami, T.; Nurwantoro; Yunianto, V. D.

2018-01-01

The research goal is knowing of the characteristict of salt fermented meat by Pediococcus ssp. There were microbiological, chemical, and off-flavor compound during fermentation. This study was conducted on research of influence of salt-meat fermentation inoculated used starter. They were included microbiological characteristics, and chemical characteristics. Microbiological characteristics observed were total bacteria, number of coliform groups, bacteria producing bioamine, and total lactic acid bacteria. The result showed that decreasing of coliform and bioamine producer bacteria, and total lactic acid bacteria decreased 3 log cycle. While the soluble protein increased of 7-8% and bioamine increased of 5-6 mg/100 g. And then Off-flavour compound, TVN and TMA increased of 36-20 mg/100g and 16-30 mg/100g, respectively. Conclusion of the research that Pedioccoccus ssp. influenced salt fermented meat.

Mutant E. coli strain with increased succinic acid production

DOEpatents

Donnelly, Mark; Millard, Cynthia S.; Stols, Lucy

1998-01-01

A method for isolating succinic acid producing bacteria is provided comprising increasing the biomass of an organism which lacks the ability to catabolize pyruvate, and then subjecting the biomass to glucose-rich medium in an anaerobic environment to enable pyruvate-catabolizing mutants to grow. The invention also provides for a mutant that produces high amounts of succinic acid, which as been derived from a parent which lacked the genes for pyruvate formate lyase and lactate dehydrogenase, and which belongs to the E.coli Group of Bacteria.

Mutant E. coli strain with increased succinic acid production

DOEpatents

Donnelly, Mark; Millard, Cynthia S.; Stols, Lucy

2001-09-25

A method for isolating succinic acid producing bacteria is provided comprising increasing the biomass of an organism which lacks the ability to catabolize pyruvate, and then subjecting the biomass to glucose-rich medium in an anaerobic environment to enable pyruvate-catabolizing mutants to grow. The invention also provides for a mutant that produces high amounts of succinic acid, which has been derived from a parent which lacked the genes for pyruvate formate lyase and lactate dehydrogenase, and which belongs to the E.coli Group of Bacteria.

Mutant E. coli strain with increased succinic acid production

DOEpatents

Donnelly, Mark; Millard, Cynthia S.; Stols, Lucy

2002-01-01

A method for isolating succinic acid producing bacteria is provided comprising increasing the biomass of an organism which lacks the ability to catabolize pyruvate, and then subjecting the biomass to glucose-rich medium in an anaerobic environment to enable pyruvate-catabolizing mutants to grow. The invention also provides for a mutant that produces high amounts of succinic acid, which has been derived from a parent which lacked the genes for pyruvate formate lyase and lactate dehydrogenase, and which belongs to the E.coli Group of Bacteria.

Amino acid–based surfactants: New antimicrobial agents.

PubMed

Pinazo, A; Manresa, M A; Marques, A M; Bustelo, M; Espuny, M J; Pérez, L

2016-02-01

The rapid increase of drug resistant bacteria makes necessary the development of new antimicrobial agents. Synthetic amino acid-based surfactants constitute a promising alternative to conventional antimicrobial compounds given that they can be prepared from renewable raw materials. In this review, we discuss the structural features that promote antimicrobial activity of amino acid-based surfactants. Monocatenary, dicatenary and gemini surfactants that contain different amino acids on the polar head and show activity against bacteria are revised. The synthesis and basic physico-chemical properties have also been included.

The effect of eubiotic feed additives on the performance of growing pigs and the activity of intestinal microflora.

PubMed

Nowak, Piotr; Kasprowicz-Potocka, Małgorzata; Zaworska, Anita; Nowak, Włodzimierz; Stefańska, Barbara; Sip, Anna; Grajek, Włodzimierz; Juzwa, Wojciech; Taciak, Marcin; Barszcz, Marcin; Tuśnio, Anna; Grajek, Katarzyna; Foksowicz-Flaczyk, Joanna; Frankiewicz, Andrzej

2017-12-01

The aim of this study was to compare the effect of probiotic bacteria, prebiotics, phytobiotics and their combinations on performance and microbial activity in the digestive tract of growing pigs. The experiment was conducted over 28 d on 48 male pigs of about 12 kg body weight (BW), which were allocated to following treatments.: (1) Control Group (Con) without additive, (2) Group I, addition of a prebiotic (inulin), (3) Group Ph, a phytobiotic (herbal water extracts), (4) Group P, a probiotic composed of four strains of lactic acid bacteria, (5) Group PhP, phytobiotic and probiotic bacteria and (6) Group PhPI, a phytobiotic, probiotic bacteria and a prebiotic. Animal performance was recorded and at d 28 six pigs from each group were euthanised to collect digesta samples. In all groups except for Group I, diarrhoea incidents were observed. Groups Ph and P had significantly higher daily gains and final BW, and Group Ph utilised feed better than other groups. The pH of ileal digesta was significantly lower in Group PhPI. In the caecal digesta of Groups I, P and PhP, the pH level was lower than in the other groups but dry matter contents was significantly higher in Groups Con and I. The short-chain fatty acids and particular acid content differed significantly only in the colonic digesta. The yeast and mould numbers in caecal digesta was highest in Group Con. No treatment effects were observed for the number of lactic acid bacteria, coli group bacteria or Clostridium. However, the observed significantly higher number of total bacteria suggests that a multi-component eubiotic treatment changes the bacterial composition and distribution more effectively. Our findings indicated that all used additives changed the intestinal microflora, but the multi-component eubiotics were not beneficial as feed additives offered separately. Moreover, supplementation of phytobiotics and probiotic bacteria also improved the animal performance significantly.

Antibacterial characteristics of newly developed amphiphilic lipids and DNA-lipid complexes against bacteria.

PubMed

Inoue, Y; Fukushima, T; Hayakawa, T; Takeuchi, H; Kaminishi, H; Miyazaki, K; Okahata, Y

2003-05-01

The purpose of this study was to investigate the antibacterial activity of newly developed amphiphilic lipids and DNA/lipid complexes against two types of oral bacteria and two types of hospital infection bacteria. Nine amphiphilic lipids were quantitatively prepared from the reaction of n-alkyl alcohol, alpha-amino acids, and p-toluenesulfonic acid. Nine DNA-lipid complexes were prepared by the simple mixing of DNA and amphiphilic lipids. The DNA-lipid complexes were insoluble in water. The antibacterial activity of lipids and DNA-lipid complexes against Porphyromonas gingivalis, Streptococcus mutans, Staphylococcus aureus, and Pseudomonas aeruginosa were evaluated by the disk-diffusion method. Seven artificial lipids showed antibacterial behavior; in particular, the lipids prepared from n-decyl alcohol and glycine and from n-decyl alcohol and L-alanine showed antibacterial activity against the four bacterial strains used in this study. On the other hand, the lipids of glutamic acid derivatives did not show any antibacterial activity against the four bacteria strains except for the lipid with an n-octyl group. Five DNA-lipid complexes also had an antibacterial effect. The complex prepared from DNA and glycine decyl ester p-toluenesulfonic acid salt exhibited antibacterial activity against the four types of bacteria strains. In this study it was found that lipids and DNA-lipid complexes with a mono-decyl group or a mono-dodecyl group have more favorable antibacterial activity. Copyright 2003 Wiley Periodicals, Inc.

Trace Amounts of Furan-2-Carboxylic Acids Determine the Quality of Solid Agar Plates for Bacterial Culture

PubMed Central

Hara, Shintaro; Isoda, Reika; Tahvanainen, Teemu; Hashidoko, Yasuyuki

2012-01-01

Background Many investigators have recognised that a significant proportion of environmental bacteria exist in a viable but non-culturable state on agar plates, and some researchers have also noticed that some of such bacteria clearly recover their growth on matrices other than agar. However, the reason why agar is unsuitable for the growth of some bacteria has not been addressed. Methodology/Principal Findings According to the guide of a bioassay for swarming inhibition, we identified 5-hydroxymethylfuran-2-carboxylic acid (5-HMFA) and furan-2-carboxylic acid (FA) as factors that inhibit bacterial swarming and likely inhibit extracellular polysaccharide production on agar. The furan-2-carboxylic acids 5-HMFA and FA effectively inhibited the swarming and swimming of several environmental bacteria at concentrations of 1.8 and 2.3 µg L−1 (13 and 21 nmol L−1), respectively, which are equivalent to the concentrations of these compounds in 0.3% agar. On Luria-Bertani (LB) plates containing 1.0% agar that had been previously washed with MeOH, a mixture of 5-HMFA and FA in amounts equivalent to their original concentrations in the unwashed agar repressed the swarming of Escherichia coli K12 strain W3110, a representative swarming bacterium. Conclusions/Significance Agar that contains trace amounts of 5-HMFA and FA inhibits the proliferation of some slow-growing or difficult-to-culture bacteria on the plates, but it is useful for single colony isolation due to the ease of identification of swarmable bacteria as the non-swarmed colonies. PMID:22848437

Phenotypic and genotypic characterization of lactic acid bacteria isolated from raw goat milk and effect of farming practices on the dominant species of lactic acid bacteria.

PubMed

Tormo, Hélène; Ali Haimoud Lekhal, Djamila; Roques, C

2015-10-01

Lactic acid bacteria, in particular Lactococcus lactis, play a decisive role in the cheese making process and more particularly in lactic cheeses which are primarily produced on goat dairy farms. The objective of this study was therefore to identify the main lactic acid bacteria found in raw goats' milk from three different regions in France and evaluate if certain farming practices have an effect on the distribution of species of lactic acid bacteria in the various milk samples. Identification at genus or species level was carried out using phenotypic tests and genotypic methods including repetitive element REP-PCR, species-specific PCR and 16S rRNA gene sequencing. The distribution of the main bacterial species in the milk samples varied depending on farms and their characteristics. Out of the 146 strains identified, L. lactis was the dominant species (60% of strains), followed by Enterococcus (38%) of which Enterococcus faecalis and Enterococcus faecium. Within the species L. lactis, L. lactis subsp lactis was detected more frequently than L. lactis subsp cremoris (74% vs. 26%). The predominance of L. lactis subsp cremoris was linked to geographical area studied. It appears that the animals' environment plays a role in the balance between the dominance of L. lactis and enterococci in raw goats' milk. The separation between the milking parlor and the goat shed (vs no separation) and only straw in the bedding (vs straw and hay) seems to promote L. lactis in the milk (vs enterococci). Copyright © 2015 Elsevier B.V. All rights reserved.

Isolation and Structural Elucidation of Brevibacillin, an Antimicrobial Lipopeptide from Brevibacillus laterosporus That Combats Drug-Resistant Gram-Positive Bacteria.

PubMed

Yang, Xu; Huang, En; Yuan, Chunhua; Zhang, Liwen; Yousef, Ahmed E

2016-05-01

A new environmental bacterial strain exhibited strong antimicrobial characteristics against methicillin-resistant Staphylococcus aureus, vancomycin-resistant strains of Enterococcus faecalis and Lactobacillus plantarum, and other Gram-positive bacteria. The producer strain, designated OSY-I1, was determined to be Brevibacillus laterosporusvia morphological, biochemical, and genetic analyses. The antimicrobial agent was extracted from cells of OSY-I1 with isopropanol, purified by high-performance liquid chromatography, and structurally analyzed using mass spectrometry (MS) and nuclear magnetic resonance (NMR). The MS and NMR results, taken together, uncovered a linear lipopeptide consisting of 13 amino acids and an N-terminal C6 fatty acid (FA) chain, 2-hydroxy-3-methylpentanoic acid. The lipopeptide (FA-Dhb-Leu-Orn-Ile-Ile-Val-Lys-Val-Val-Lys-Tyr-Leu-valinol, where Dhb is α,β-didehydrobutyric acid and valinol is 2-amino-3-methyl-1-butanol) has a molecular mass of 1,583.0794 Da and contains three modified amino acid residues: α,β-didehydrobutyric acid, ornithine, and valinol. The compound, designated brevibacillin, was determined to be a member of a cationic lipopeptide antibiotic family. In addition to its potency against drug-resistant bacteria, brevibacillin also exhibited low MICs (1 to 8 μg/ml) against selected foodborne pathogenic and spoilage bacteria, such as Listeria monocytogenes,Bacillus cereus, and Alicyclobacillus acidoterrestris Purified brevibacillin showed no sign of degradation when it was held at 80 °C for 60 min, and it retained at least 50% of its antimicrobial activity when it was held for 22 h under acidic or alkaline conditions. On the basis of these findings, brevibacillin is a potent antimicrobial lipopeptide which is potentially useful to combat drug-resistant bacterial pathogens and foodborne pathogenic and spoilage bacteria. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Evidence for Lignin Oxidation by the Giant Panda Fecal Microbiome

PubMed Central

Zhou, Peng; Chang, Fei; Hong, Yuzhi; Zhang, Xuecheng; Peng, Hui; Xiao, Yazhong

2012-01-01

The digestion of lignin and lignin-related phenolic compounds from bamboo by giant pandas has puzzled scientists because of the lack of lignin-degrading genes in the genome of the bamboo-feeding animals. We constructed a 16S rRNA gene library from the microorganisms derived from the giant panda feces to identify the possibility for the presence of potential lignin-degrading bacteria. Phylogenetic analysis showed that the phylotypes of the intestinal bacteria were affiliated with the phyla Proteobacteria (53%) and Firmicutes (47%). Two phylotypes were affiliated with the known lignin-degrading bacterium Pseudomonas putida and the mangrove forest bacteria. To test the hypothesis that microbes in the giant panda gut help degrade lignin, a metagenomic library of the intestinal bacteria was constructed and screened for clones that contained genes encoding laccase, a lignin-degrading related enzyme. A multicopper oxidase gene, designated as lac51, was identified from a metagenomic clone. Sequence analysis and copper content determination indicated that Lac51 is a laccase rather than a metallo-oxidase and may work outside its original host cell because it has a TAT-type signal peptide and a transmembrane segment at its N-terminus. Lac51 oxidizes a variety of lignin-related phenolic compounds, including syringaldazine, 2,6-dimethoxyphenol, ferulic acid, veratryl alcohol, guaiacol, and sinapinic acid at conditions that simulate the physiologic environment in giant panda intestines. Furthermore, in the presence of 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), syringic acid, or ferulic acid as mediators, the oxidative ability of Lac51 on lignin was promoted. The absorbance of lignin at 445 nm decreased to 36% for ABTS, 51% for syringic acid, and 51% for ferulic acid after incubation for 10 h. Our findings demonstrate that the intestinal bacteria of giant pandas may facilitate the oxidation of lignin moieties, thereby clarifying the digestion of bamboo lignin by the animal. PMID:23209704

Antimicrobial activity of fractions and compounds from Calophyllumbrasiliense (Clusiaceae/Guttiferae).

PubMed

Pretto, Juliana B; Cechinel-Filho, Valdir; Noldin, Vânia F; Sartori, Mara R K; Isaias, Daniela E B; Cruz, Alexandre Bella

2004-01-01

Calophyllum brasiliense (Clusiaceae/Guttiferae) is a native Brazilian medicinal plant traditionally used against several diseases, including infectious pathologies. Crude methanolic extracts (CME) and two fractions, denoted non-polar (soluble in chloroform) and polar (nonsoluble in chloroform), were prepared from different parts of the plant (roots, stems, leaves, flowers and fruits) and studied. The following compounds were isolated and tested against pathogenic bacteria and yeasts by determination of the minimal inhibitory concentration (MIC): brasiliensic acid (1), gallic acid (2), epicatechin (3), protocatechuic acid (4), friedelin (5) and 1,5-dihydroxyxanthone (6). The results indicated that all the parts of the plant exhibited antimicrobial activity against Gram-positive bacteria, which are selectively inhibited by components of C. brasiliense. No activity was observed against Gram-negative bacteria and yeasts tested. Regarding the isolated compounds, substance 4 showed antimicrobial activity against all the tested microorganisms, whereas compound 6 exhibited antimicrobial activity only against Gram-positive bacteria. The results from the current study confirm and justify the popular use of this plant to treat infectious processes.

Lipoquinones of some spore-forming rods, lactic-acid bacteria and actinomycetes.

PubMed

Hess, A; Holländer, R; Mannheim, W

1979-11-01

The respiratory quinones of 73 strains of Gram-positive bacteria including spore-forming rods, lactic-acid bacteria and actinomyctes were examined. Menaquinones with seven isoprenoid units (MK-7) were the main quinone type found in representatives of the genus Bacillus and in Sporolactobacillus inulinus. However, a strain of B. thuringiensis produced MK-8 in addition to MK-7, and strains of B. lentus and B. pantothenticus appeared to produce MK-9 and MK-8, respectively, with no MK-7. In the clostridia and lactic-acid bacteria, no quinones were found, except in Pediococcus cerevisiae NCTC 8066 and Lactobacillus casei subsp. rhamnosus ATCC 7469, which contained menaquinones, and Streptococcus faecalis NCTC 775 and HIM 478-1, which contained demethylmenaquinones, in relatively low concentrations. Menaquinones were also found in the actinomycetes (except Actinomyces odontolyticus and Bifidobacterium bifidum which did not produce any quinones) and in Protaminobacter alboflavus ATCC 8458, the so-called Actinobacillus actinoides ATCC 15900 and Noguchia granulosis NCTC 10559.

Incorporating zosteric acid into silicone coatings to achieve its slow release while reducing fresh water bacterial attachment.

PubMed

Barrios, Carlos A; Xu, Qingwei; Cutright, Teresa; Newby, Bi-min Zhang

2005-03-25

Biofouling has posed serious problems in maritime industry including increased fuel consumptions, economic loss from ship-hull maintenances, contamination of drinking water, and serious corrosion for mechanical instruments. Minimizing the attachment of bacteria and formation of biofilm could be advantageous in reducing the early stages of biofouling. Zosteric acid, a natural product present in eelgrass, was found to have ability for preventing the attachment of some bacteria and barnacles. In this study, the antifouling ability of zosteric acid during the early stages of fouling was evaluated using attachment studies of fresh water bacteria. Simultaneously, various methods were sought for incorporating zosteric acid into silicone to prolong the release of the compound. The main results from this study were that zosteric acid exhibited anti-bacterial attachment regardless of whether it dispersed in water or incorporated into a coating. In addition, the release rate of zosteric acid from the incorporated coatings, particularly those where zosteric acid was uniformly dispersed with aggregates size of 4 microm or less, was orders of magnitude slower than those of previous reports. The release results indicate that the service life of our coatings could be far extended even with a small amount of zosteric acid incorporated.

Generation of volatile fatty acids by axillary bacteria.

PubMed

James, A G; Hyliands, D; Johnston, H

2004-06-01

It is generally accepted that short-chain (C(2)-C(5)) volatile fatty acids (VFAs) are among the causal molecules of axillary malodour. It is also widely acknowledged that malodour generation is attributable to the biotransformation of odourless natural secretions, into volatile odorous products, by axillary bacteria. However, little information is available on the biochemical origins of VFAs on axillary skin. In these studies, assay systems were developed to investigate the generation of VFAs from substrates readily available to the bacteria resident on axillary skin. Propionibacteria and staphylococci were shown to ferment glycerol and lactic acid to the short-chain (C(2)-C(3)) VFAs, acetic and propionic acid. Furthermore, staphylococci are capable of converting branched aliphatic amino acids, such as leucine, to highly odorous short-chain (C(4)-C(5)) methyl-branched VFAs, such as isovaleric acid, which are traditionally associated with the acidic note of axillary malodour. However, in vitro kinetic data indicates that these pathways contribute less to axillary VFA levels, than fatty acid biotransformations by a recently defined sub-group of the Corynebacterium genus, corynebacteria (A). The results of these studies provide new understanding on the biochemical origins of VFA-based axillary malodour which, in turn, should lead to the development of novel deodorant systems.

THE PRODUCTION OF VOLATILE FATTY ACIDS BY BACTERIA OF THE DYSENTERY GROUP

PubMed Central

Zoller, Harper F.; Clark, W. Mansfield

1921-01-01

These studies show: 1. A close agreement exists among all the organisms studied in the total quantity of volatile fatty acids produced and in the ratio of formic to acetic, under aerobic conditions, and in the presence of 1 per cent of glucose. 2. When grown upon peptone alone, with free access of air to the cultures, volatile fatty acids are produced in appreciable quantities, although the reaction of the solution has gone more alkaline as shown by colorimetric pH tests. Formic acid is not found, but in its place we obtain propionic acid. 3. Upon exhaustion of air from the non-sugar medium the bacteria again produce formic acid, and in addition some butyric. This is true for both Shiga and non-Shiga cultures. The reaction is distinctly more acid. 4. The presence of glucose in the medium from which the air has been pumped furnishes a condition which provokes about the same type and degree of fermentation that operates in the glucose medium bathed in air at atmospheric pressure. 5. The enormous quantity of formic acid produced by these bacteria may play a significant part in the digestive disturbances and toxic symptoms accompanying their infection of the human intestinal tract. PMID:19871867

Differing Daphnia magna assimilation efficiencies for terrestrial, bacterial, and algal carbon and fatty acids.

PubMed

Taipale, Sami J; Brett, Michael T; Hahn, Martin W; Martin-Creuzburg, Dominik; Yeung, Sean; Hiltunen, Minna; Strandberg, Ursula; Kankaala, Paula

2014-02-01

There is considerable interest in the pathways by which carbon and growth-limiting elemental and biochemical nutrients are supplied to upper trophic levels. Fatty acids and sterols are among the most important molecules transferred across the plant-animal interface of food webs. In lake ecosystems, in addition to phytoplankton, bacteria and terrestrial organic matter are potential trophic resources for zooplankton, especially in those receiving high terrestrial organic matter inputs. We therefore tested carbon, nitrogen, and fatty acid assimilation by the crustacean Daphnia magna when consuming these resources. We fed Daphnia with monospecific diets of high-quality (Cryptomonas marssonii) and intermediate-quality (Chlamydomonas sp. and Scenedesmus gracilis) phytoplankton species, two heterotrophic bacterial strains, and particles from the globally dispersed riparian grass, Phragmites australis, representing terrestrial particulate organic carbon (t-POC). We also fed Daphnia with various mixed diets, and compared Daphnia fatty acid, carbon, and nitrogen assimilation across treatments. Our results suggest that bacteria were nutritionally inadequate diets because they lacked sterols and polyunsaturated omega-3 and omega-6 (omega-3 and omega-6) fatty acids (PUFAs). However, Daphnia were able to effectively use carbon and nitrogen from Actinobacteria, if their basal needs for essential fatty acids and sterols were met by phytoplankton. In contrast to bacteria, t-POC contained sterols and omega-6 and omega-3 fatty acids, but only at 22%, 1.4%, and 0.2% of phytoplankton levels, respectively, which indicated that t-POC food quality was especially restricted with regard to omega-3 PUFAs. Our results also showed higher assimilation of carbon than fatty acids from t-POC and bacteria into Daphnia, based on stable-isotope and fatty acids analysis, respectively. A relatively high (>20%) assimilation of carbon and fatty acids from t-POC was observed only when the proportion of t-POC was >60%, but due to low PUFA to carbon ratio, these conditions yielded poor Daphnia growth. Because of lower assimilation for carbon, nitrogen, and fatty acids from t-POC relative to diets of bacteria mixed with phytoplankton, we conclude that the microbial food web, supported by phytoplankton, and not direct t-POC consumption, may support zooplankton production. Our results suggest that terrestrial particulate organic carbon poorly supports upper trophic levels of the lakes.

Use of agar diffusion assay to evaluate bactericidal activity of formulations of alkaline salts of fatty acids against bacteria associated with poultry processing

USDA-ARS?s Scientific Manuscript database

The agar diffusion assay was used to examine antibacterial activity of alkaline salts of fatty acids (FA). Wells in agar media seeded with bacteria were filled with FA-potassium hydroxide (KOH) solutions, plates were incubated, and zones of inhibition were measured. The relationship between bacteric...

An ability of endophytic bacteria from nutgrass (cyperus rotundus) from lafau beach of north nias in producing indole acetic acid and in solubilizing phosphate

NASA Astrophysics Data System (ADS)

Zega, Atriani; Suryanto, Dwi; Yurnaliza

2018-03-01

Endophytic bacteria have taken much attention for their potency to promote plant growth. This study was aimed to isolate endophytic bacteria from nutgrass (Cyperus rotundus) and to examine their potency in producing indole acetic acid (IAA) and in solubilizing phosphate. Isolation of endophytic bacteria was done by slicing and sterilizing root, stem, and leaf sample surface with alcohol 70% and sodium hypochlorite 2%, followed by incubation of the sliced samples in nutrient agar medium. Morphological characterization and simple biochemical tests were performed on bacterial isolates. All bacterial isolates were examined for their ability to produce indole acetic acid and to solubilize phosphate. Three isolates (AZ5, AZ12 and AZ6) out of fifteen indicated the ability to produce indole acetic acid and to solubilize phosphate. IAA producing test using spectrophotometry method showed that AZ5, AZ12,and AZ6 produce more IAA with concentration of 49,91, 48,18, and 44,45 ppm, respectively. Phosphate solubilizing test using Pikovskaya agar medium showed that the three isolates were able to solubilize phosphate with index of 6.27, 3,31, and 3.41 respectively.

Small molecule inhibitor of lipoteichoic acid synthesis is an antibiotic for Gram-positive bacteria

PubMed Central

Richter, Stefan G.; Elli, Derek; Kim, Hwan Keun; Hendrickx, Antoni P. A.; Sorg, Joseph A.; Schneewind, Olaf; Missiakas, Dominique

2013-01-01

The current epidemic of infections caused by antibiotic-resistant Gram-positive bacteria requires the discovery of new drug targets and the development of new therapeutics. Lipoteichoic acid (LTA), a cell wall polymer of Gram-positive bacteria, consists of 1,3-polyglycerol-phosphate linked to glycolipid. LTA synthase (LtaS) polymerizes polyglycerol-phosphate from phosphatidylglycerol, a reaction that is essential for the growth of Gram-positive bacteria. We screened small molecule libraries for compounds inhibiting growth of Staphylococcus aureus but not of Gram-negative bacteria. Compound 1771 [2-oxo-2-(5-phenyl-1,3,4-oxadiazol-2-ylamino)ethyl 2-naphtho[2,1-b]furan-1-ylacetate] blocked phosphatidylglycerol binding to LtaS and inhibited LTA synthesis in S. aureus and in Escherichia coli expressing ltaS. Compound 1771 inhibited the growth of antibiotic-resistant Gram-positive bacteria and prolonged the survival of mice with lethal S. aureus challenge, validating LtaS as a target for the development of antibiotics. PMID:23401520

Antagonistic activity of isolated lactic acid bacteria from Pliek U against gram-negative bacteria Escherichia coli ATCC 25922

NASA Astrophysics Data System (ADS)

Kiti, A. A.; Jamilah, I.; Rusmarilin, H.

2017-09-01

Lactic acid bacteria (LAB) is one group of microbes that has many benefits, notably in food and health industries sector. LAB plays an important role in food fermentation and it has bacteriostatic effect against the growth of pathogenic microorganisms. The research related LAB continued to be done to increase the diversity of potential isolates derived from nature which is indigenous bacteria for biotechnological purposes. This study was aimed to isolate and characterize LAB derived from pliek u sample and to examine the potency to inhibits Escherichia coli ATCC 25922 bacteria growth. A total of 5 isolates were isolated and based on morphological and physiological characteristics of the fifth bacteria, they are allegedly belonging to the genus Bacillus. Result of antagonistic test showed that the five isolates could inhibits the growth of E. coli ATCC 25922. The highest inhibition zone is 8.5 mm was shown by isolates NQ2, while the lowest inhibition is 1.5 mm was shown by isolates NQ3.

Carbonate crystals precipitated by freshwater bacteria and their use as a limestone consolidant.

PubMed

Zamarreño, Dania V; Inkpen, Robert; May, Eric

2009-09-01

Bacterial carbonate precipitation is known to be a natural phenomenon associated with a wide range of bacterial species. Recently, the ability of bacteria to produce carbonates has been studied for its value in the conservation of limestone monuments and concrete. This paper describes investigations of carbonate crystals precipitated by freshwater bacteria by means of histological (Loeffler's methylene blue and alcian blue-periodic acid-Schiff stain) and fluorescence (CTC [5-cyano-2,3-ditolyl tetrazolium chloride]) stains, determination of cell viability inside carbonate crystals, and pore size reduction in limestone by image analysis. Carbonate crystals were found to be composed of bacteria embedded in a matrix of neutral and acid polysaccharides. Cell viability inside the carbonate crystals decreased with time. On stone, bacteria were found to form carbonate crystals, with only a few bacteria remaining as isolated cells or as cell aggregates. Pore size was reduced by about 50%, but no blockage was detected. Taken together, the results of this research provide some reassurance to conservators that biocalcification by bacteria could be a safe consolidation tool in a restoration strategy for building stone conservation.

Carbonate Crystals Precipitated by Freshwater Bacteria and Their Use as a Limestone Consolidant▿

PubMed Central

Zamarreño, Dania V.; Inkpen, Robert; May, Eric

2009-01-01

Bacterial carbonate precipitation is known to be a natural phenomenon associated with a wide range of bacterial species. Recently, the ability of bacteria to produce carbonates has been studied for its value in the conservation of limestone monuments and concrete. This paper describes investigations of carbonate crystals precipitated by freshwater bacteria by means of histological (Loeffler's methylene blue and alcian blue-periodic acid-Schiff stain) and fluorescence (CTC [5-cyano-2,3-ditolyl tetrazolium chloride]) stains, determination of cell viability inside carbonate crystals, and pore size reduction in limestone by image analysis. Carbonate crystals were found to be composed of bacteria embedded in a matrix of neutral and acid polysaccharides. Cell viability inside the carbonate crystals decreased with time. On stone, bacteria were found to form carbonate crystals, with only a few bacteria remaining as isolated cells or as cell aggregates. Pore size was reduced by about 50%, but no blockage was detected. Taken together, the results of this research provide some reassurance to conservators that biocalcification by bacteria could be a safe consolidation tool in a restoration strategy for building stone conservation. PMID:19617383

Assessment of active bacteria metabolizing phenolic acids in the peanut (Arachis hypogaea L.) rhizosphere.

PubMed

Liu, Jinguang; Wang, Xingxiang; Zhang, Taolin; Li, Xiaogang

2017-12-01

Phenolic acids can enhance the mycotoxin production and activities of hydrolytic enzymes related to pathogenicity of soilborne fungus Fusarium oxysporum. However, characteristics of phenolic acid-degrading bacteria have not been investigated. The objectives of this study were to isolate and characterize bacteria capable of growth on benzoic and vanillic acids as the sole carbon source in the peanut rhizosphere. Twenty-four bacteria were isolated, and the identification based on 16S rRNA gene sequencing revealed that pre-exposure to phenolic acids before sowing shifted the dominant culturable bacterial degraders from Arthrobacter to Burkholderia stabilis-like isolates. Both Arthrobacter and B. stabilis-like isolates catalysed the aromatic ring cleavage via the ortho pathway, and Arthrobacter isolates did not exhibit higher C12O enzyme activity than B. stabilis-like isolates. The culture filtrate of Fusarium sp. ACCC36194 caused a strong inhibition of Arthrobacter growth but not B. stabilis-like isolates. Additionally, Arthrobacter isolates responded differently to the culture filtrates of B. stabilis-like isolates. The Arthrobacter isolates produced higher indole acetic acid (IAA) levels than B. stabilis-like isolates, but B. stabilis-like isolates were also able to produce siderophores, solubilize mineral phosphate, and exert an antagonistic activity against peanut root rot pathogen Fusarium sp. ACCC36194. Results indicate that phenolic acids can shift their dominant culturable bacterial degraders from Arthrobacter to Burkholderia species in the peanut rhizosphere, and microbial interactions might lead to the reduction of culturable Arthrobacter. Furthermore, increasing bacterial populations metabolizing phenolic acids in monoculture fields might be a control strategy for soilborne diseases caused by Fusarium spp. Copyright © 2017 Elsevier GmbH. All rights reserved.

Lactic acid fermentation of cassava dough into agbelima.

PubMed

Amoa-Awua, W K; Appoh, F E; Jakobsen, M

1996-08-01

The souring of cassava dough during fermentation into the fermented cassava meal, agbelima, was investigated. Four different types of traditional inocula were used to ferment the dough and increases in titrable acidity expressed as lactic acid from 0.31-0.38 to 0.78-0.91% (w/w) confirmed the fermentation to be a process of acidification. The microflora of all inocula and fermenting dough contained high counts of lactic acid bacteria, 10(8)-10(9) cfu/g in all inocula and 10(7)-10(8), 10(8)-10(9) and 10(9) cfu/g at 0, 24 and 48 h in all fermentations. Lactobacillus plantarum was the dominant species of lactic acid bacteria during all types of fermentation accounting for 51% of 171 representative isolates taken from various stages of fermentation. Other major lactic acid bacteria found were Lactobacillus brevis, 16%, Leuconostoc mesenteroides, 15% and some cocci including Streptococcus spp. whose numbers decreased with fermentation time. The lactic acid bacteria were responsible for the souring of agbelima through the production of lactic acid. All L. plantarum, L. brevis and L. mesenteroides isolates examined demonstrated linamarase as well as other enzymatic activities but did not possess tissue degrading enzymes like cellulase, pectin esterase and polygalacturonase. The aroma profile of agbelima did not vary with the type of inoculum used and in all samples the build-up of aroma compounds were dominated by a non-identified low molecular weight alcohol, 1-propanol, isoamyl alcohol, ethyl acetate, 3-methyl-1-butanol and acetoin. Substantial reductions occurred in the levels of cyanogenic compounds present in cassava during fermentation into agbelima and detoxification was enhanced by the use of inoculum.

[Application of anaerobic bacteria detection in oral and maxillofacial infection].

PubMed

Bao, Zhen-ying; Lin, Qin; Meng, Yan-hong; He, Chun; Su, Jia-zeng; Peng, Xin

2016-02-18

To investigate the distribution and drug resistance of anaerobic bacteria in the patients with oral and maxillofacial infection. Aerobic and anaerobic bacteria cultures from 61 specimens of pus from the patients with oral and maxillofacial infection in the Department of Oral and Maxillofacial Surgery, Peking University School of Stomatology were identified. The culture type was evaluated by API 20A kit and drug resistance test was performed by Etest method. The clinical data and antibacterial agents for the treatment of the 61 cases were collected, and the final outcomes were recorded. The bacteria cultures were isolated from all the specimens, with aerobic bacteria only in 6 cases (9.8%), anaerobic bacteria only in 7 cases (11.5%), and both aerobic and anaerobic bacteria in 48 cases (78.7%). There were 55 infected cases (90.2%) with anaerobic bacteria, and 81 anaerobic bacteria stains were isolated. The highest bacteria isolation rate of Gram positive anaerobic bacteria could be found in Peptostreptococcus, Bifidobacterium and Pemphigus propionibacterium. No cefoxitin, amoxicillin/carat acid resistant strain was detected in the above three Gram positive anaerobic bacteria. The highest bacteria isolation rate of Gram negative anaerobic bacteria could be detected in Porphyromonas and Prevotella. No metronidazole, cefoxitin, amoxicillin/carat acid resistant strain was found in the two Gram negative anaerobic bacteria. In the study, 48 patients with oral and maxillofacial infection were treated according to the results of drug resistance testing, and the clinical cure rate was 81.3%. Mixed aerobic and anaerobic bacteria cultures are very common in most oral and maxillofacial infection patients. Anaerobic bacteria culture and drug resistance testing play an important role in clinical treatment.

Monitoring the dynamics of syntrophic β-oxidizing bacteria during anaerobic degradation of oleic acid by quantitative PCR.

PubMed

Ziels, Ryan M; Beck, David A C; Martí, Magalí; Gough, Heidi L; Stensel, H David; Svensson, Bo H

2015-04-01

The ecophysiology of long-chain fatty acid-degrading syntrophic β-oxidizing bacteria has been poorly understood due to a lack of quantitative abundance data. Here, TaqMan quantitative PCR (qPCR) assays targeting the 16S rRNA gene of the known mesophilic syntrophic β-oxidizing bacterial genera Syntrophomonas and Syntrophus were developed and validated. Microbial community dynamics were followed using qPCR and Illumina-based high-throughput amplicon sequencing in triplicate methanogenic bioreactors subjected to five consecutive batch feedings of oleic acid. With repeated oleic acid feeding, the initial specific methane production rate significantly increased along with the relative abundances of Syntrophomonas and methanogenic archaea in the bioreactor communities. The novel qPCR assays showed that Syntrophomonas increased from 7 to 31% of the bacterial community 16S rRNA gene concentration, whereas that of Syntrophus decreased from 0.02 to less than 0.005%. High-throughput amplicon sequencing also revealed that Syntrophomonas became the dominant genus within the bioreactor microbiomes. These results suggest that increased specific mineralization rates of oleic acid were attributed to quantitative shifts within the microbial communities toward higher abundances of syntrophic β-oxidizing bacteria and methanogenic archaea. The novel qPCR assays targeting syntrophic β-oxidizing bacteria may thus serve as monitoring tools to indicate the fatty acid β-oxidization potential of anaerobic digester communities. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Purification of bacteriocins produced by lactic acid bacteria.

PubMed

Saavedra, Lucila; Castellano, Patricia; Sesma, Fernando

2004-01-01

Bacteriocins are antibacterial substances of a proteinaceous nature that are produced by different bacterial species. Lactic acid bacteria (LAB) produce biologically active peptides or protein complexes that display a bactericidal mode of action almost exclusively toward Gram-positive bacteria and particularly toward closely related species. Generally they are active against food spoilage and foodborne pathogenic microorganisms including Bacillus cereus, Clostridium perfringens, Staphylococcus aureus, and Listeria monocytogenes. There is an increased tendency to use natural occurring metabolites to prevent the growth of undesirable flora in foodstuffs. These metabolites could replace the use of chemical additives such as sorbic acid, sulfur dioxide, nitrite, nitrate, and others. For instance, bacteriocins produced by LAB may be promising for use as bio-preservaties. Bacteriocins of lactic acid bacteria are typically cationic, hydrophobic peptides and differ widely in many characteristics including molecular weight, presence of particular groups of amino acids, pI, net positive charge, and post-translational modifications of certain amino acids. This heterogeneity within the LAB bacteriocins may explain the different procedures for isolation and purification developed so far. The methods most frequently used for isolation, concentration, and purification involve salt precipitation of bacteriocins from culture supernatants, followed by various combinations of gel filtration, ion-exchange chromatography, and reverse-phase high-performance liquid chromatography (RP-HPLC). In this chapter, a protocol is described that combines several methods used in our laboratory for the purification of two cationic bacteriocins, Lactocin 705AL and Enterocin CRL10, produced by Lactobacillus casei CRL705 and Enterococcus mundtii CRL10, respectively.

Dual-coated lactic acid bacteria: an emerging innovative technology in the field of probiotics.

PubMed

Alvarez-Calatayud, Guillermo; Margolles, Abelardo

2016-01-01

Probiotics are living micro-organisms that do not naturally have shelf life, and normally are weakly protected against the digestive action of the GI tract. A new dual coating technology has been developed in an effort to maximize survival, that is, to be able to reach the intestine alive and in sufficient numbers to confer the beneficial health effects on the host. Dual-coating of lactic acid bacteria (LAB) is the result of fourth-generation coating technology for the protection of these bacteria at least 100-fold or greater than the uncoated LAB. This innovative technique involves a first pH-dependent protein layer that protects bacteria from gastric acid and bile salt, and a second polysaccharide matrix that protects bacteria from external factors, such as humidity, temperature and pressure, as well as the digestive action during the passage through the GI tract. Dual-coated probiotic formulation is applicable to different therapeutic areas, including irritable bowel syndrome, atopic dermatitis, acute diarrhea, chronic constipation, Helicobacter pylori eradication, and prevention of antibiotic-associated diarrhea. An updated review of the efficacy of doubly coated probiotic strains for improving bacterial survival in the intestinal tract and its consequent clinical benefits in humans is here presented.

Commensal bacteria and essential amino acids control food choice behavior and reproduction

PubMed Central

Fioreze, Gabriela Tondolo; Anjos, Margarida; Baltazar, Célia; Elias, Ana Paula; Itskov, Pavel M.; Piper, Matthew D. W.

2017-01-01

Choosing the right nutrients to consume is essential to health and wellbeing across species. However, the factors that influence these decisions are poorly understood. This is particularly true for dietary proteins, which are important determinants of lifespan and reproduction. We show that in Drosophila melanogaster, essential amino acids (eAAs) and the concerted action of the commensal bacteria Acetobacter pomorum and Lactobacilli are critical modulators of food choice. Using a chemically defined diet, we show that the absence of any single eAA from the diet is sufficient to elicit specific appetites for amino acid (AA)-rich food. Furthermore, commensal bacteria buffer the animal from the lack of dietary eAAs: both increased yeast appetite and decreased reproduction induced by eAA deprivation are rescued by the presence of commensals. Surprisingly, these effects do not seem to be due to changes in AA titers, suggesting that gut bacteria act through a different mechanism to change behavior and reproduction. Thus, eAAs and commensal bacteria are potent modulators of feeding decisions and reproductive output. This demonstrates how the interaction of specific nutrients with the microbiome can shape behavioral decisions and life history traits. PMID:28441450

Commensal bacteria and essential amino acids control food choice behavior and reproduction.

PubMed

Leitão-Gonçalves, Ricardo; Carvalho-Santos, Zita; Francisco, Ana Patrícia; Fioreze, Gabriela Tondolo; Anjos, Margarida; Baltazar, Célia; Elias, Ana Paula; Itskov, Pavel M; Piper, Matthew D W; Ribeiro, Carlos

2017-04-01

Choosing the right nutrients to consume is essential to health and wellbeing across species. However, the factors that influence these decisions are poorly understood. This is particularly true for dietary proteins, which are important determinants of lifespan and reproduction. We show that in Drosophila melanogaster, essential amino acids (eAAs) and the concerted action of the commensal bacteria Acetobacter pomorum and Lactobacilli are critical modulators of food choice. Using a chemically defined diet, we show that the absence of any single eAA from the diet is sufficient to elicit specific appetites for amino acid (AA)-rich food. Furthermore, commensal bacteria buffer the animal from the lack of dietary eAAs: both increased yeast appetite and decreased reproduction induced by eAA deprivation are rescued by the presence of commensals. Surprisingly, these effects do not seem to be due to changes in AA titers, suggesting that gut bacteria act through a different mechanism to change behavior and reproduction. Thus, eAAs and commensal bacteria are potent modulators of feeding decisions and reproductive output. This demonstrates how the interaction of specific nutrients with the microbiome can shape behavioral decisions and life history traits.

Microalgae-bacteria biofilms: a sustainable synergistic approach in remediation of acid mine drainage.

PubMed

Abinandan, Sudharsanam; Subashchandrabose, Suresh R; Venkateswarlu, Kadiyala; Megharaj, Mallavarapu

2018-02-01

Microalgae and bacteria offer a huge potential in delving interest to study and explore various mechanisms under extreme environments. Acid mine drainage (AMD) is one such environment which is extremely acidic containing copious amounts of heavy metals and poses a major threat to the ecosystem. Despite its extreme conditions, AMD is the habitat for several microbes and their activities. The use of various chemicals in prevention of AMD formation and conventional treatment in a larger scale is not feasible under different geological conditions. It implies that microbe-mediated approach is a viable and sustainable alternative technology for AMD remediation. Microalgae in biofilms play a pivotal role in such bioremediation as they maintain mutualism with heterotrophic bacteria. Synergistic approach of using microalgae-bacteria biofilms provides supportive metabolites from algal biomass for growth of bacteria and mediates remediation of AMD. However, by virtue of their physiology and capabilities of metal removal, non-acidophilic microalgae can be acclimated for use in AMD remediation. A combination of selective acidophilic and non-acidophilic microalgae together with bacteria, all in the form of biofilms, may be very effective for bioremediation of metal-contaminated waters. The present review critically examines the nature of mutualistic interactions established between microalgae and bacteria in biofilms and their role in removal of metals from AMDs, and consequent biomass production for the yield of biofuel. Integration of microalgal-bacterial consortia in fuel cells would be an attractive emerging approach of microbial biotechnology for AMD remediation.

The Efficient Clade: Lactic Acid Bacteria for Industrial Chemical Production.

PubMed

Sauer, Michael; Russmayer, Hannes; Grabherr, Reingard; Peterbauer, Clemens K; Marx, Hans

2017-08-01

Lactic acid bacteria are well known to be beneficial for food production and, as probiotics, they are relevant for many aspects of health. However, their potential as cell factories for the chemical industry is only emerging. Many physiological traits of these microorganisms, evolved for optimal growth in their niche, are also valuable in an industrial context. Here, we illuminate these features and describe why the distinctive adaptation of lactic acid bacteria is particularly useful when developing a microbial process for chemical production from renewable resources. High carbon uptake rates with low biomass formation combined with strictly regulated simple metabolic pathways, leading to a limited number of metabolites, are among the key factors defining their success in both nature and industry. Copyright © 2017 Elsevier Ltd. All rights reserved.

Amino acid and fatty acid compositions of Rusip from fermented Anchovy fish (Stolephorussp)

NASA Astrophysics Data System (ADS)

Koesoemawardani, D.; Hidayati, S.; Subeki

2018-04-01

Rusip is a typical food of Bangka Belitung Indonesia made from fermented anchovy. This study aims to determine the properties of chemistry, microbiology, composition of amino acids and fatty acids from fermented fish spontaneously and non spontaneously. Spontaneous rusip treatment is done by anchovy fish (Stolephorussp) after cleaning and added salt 25% (w/w) and palm sugar 10% (w/w). While, non-spontaneous rusip is done by adding a culture mixture of Streptococcus, Leuconostoc, and Lactobacillus bacteria 2% (w/v). The materials are then incubated for 2 weeks. The data obtained were then performed t-test at the level of 5%. Spontaneous and non-spontaneous rusip fermentation process showed significant differences in total acid, reducing sugar, salt content, TVN, total lactic acid bacteria, total mold, and total microbial. The dominant amino acid content of spontaneous and non-spontaneous rusip are glutamic acid and aspartic acid, while the dominant fatty acids in spontaneous and non-spontaneous rusip are docosahexaenoic acid, palmitic acid, oleic acid, arachidonic acid, stearic acid, eicosapentaenoic acid, palmitoleic acid, and myristic acid.

Heterologous surface display on lactic acid bacteria: non-GMO alternative?

PubMed Central

Zadravec, Petra; Štrukelj, Borut; Berlec, Aleš

2015-01-01

Lactic acid bacteria (LAB) are food-grade hosts for surface display with potential applications in food and therapy. Alternative approaches to surface display on LAB would avoid the use of recombinant DNA technology and genetically-modified organism (GMO)-related regulatory requirements. Non-covalent surface display of proteins can be achieved by fusing them to various cell-wall binding domains, of which the Lysine motif domain (LysM) is particularly well studied. Fusion proteins have been isolated from recombinant bacteria or from their growth medium and displayed on unmodified bacteria, enabling heterologous surface display. This was demonstrated on non-viable cells devoid of protein content, termed bacteria-like particles, and on various species of genus Lactobacillus. Of the latter, Lactobacillus salivarius ATCC 11741 was recently shown to be particularly amenable for LysM-mediated display. Possible regulatory implications of heterologous surface display are discussed, particularly those relevant for the European Union. PMID:25880164

Heterologous surface display on lactic acid bacteria: non-GMO alternative?

PubMed

Zadravec, Petra; Štrukelj, Borut; Berlec, Aleš

2015-01-01

Lactic acid bacteria (LAB) are food-grade hosts for surface display with potential applications in food and therapy. Alternative approaches to surface display on LAB would avoid the use of recombinant DNA technology and genetically-modified organism (GMO)-related regulatory requirements. Non-covalent surface display of proteins can be achieved by fusing them to various cell-wall binding domains, of which the Lysine motif domain (LysM) is particularly well studied. Fusion proteins have been isolated from recombinant bacteria or from their growth medium and displayed on unmodified bacteria, enabling heterologous surface display. This was demonstrated on non-viable cells devoid of protein content, termed bacteria-like particles, and on various species of genus Lactobacillus. Of the latter, Lactobacillus salivarius ATCC 11741 was recently shown to be particularly amenable for LysM-mediated display. Possible regulatory implications of heterologous surface display are discussed, particularly those relevant for the European Union.

An application of polymer-enhanced capillary transient isotachophoresis with an emissive boronic acid functionalized squarylium dye as an on-capillary labeling agent for gram-positive bacteria.

PubMed

Saito, Shingo; Maeda, Takeshi; Nakazumi, Hiroyuki; Colyer, Christa L

2013-01-01

In this paper, the characterization and application of the "PectI" (polymer-enhanced capillary transient isotachophoresis) technique for the separation and detection of same genus, gram-positive bacteria, Bacillus globigii (Bg) and Bacillus subtilis, is demonstrated by employing a boronic acid-functionalized squarylium dye (SQ-BA) as an on-capillary labeling agent, including the quantitative performance and applicability to crude samples. The effect of borate in the separation buffer was also investigated, which revealed that borate strongly affects the separation behavior of bacteria.

In vitro metabolism of radiolabeled carbohydrates by protective cecal anaerobic bacteria.

PubMed

Hume, M E; Beier, R C; Hinton, A; Scanlan, C M; Corrier, D E; Peterson, D V; DeLoach, J R

1993-12-01

Cecal anaerobic bacteria from adult broilers were cultured in media containing .25% glucose or .25% lactose. Media also contained either [14C]-labeled lactose, glucose, galactose, or lactic acid as metabolic tracers. Cultures were analyzed at 4, 8, and 12 h for pH, radiolabeled and unlabeled volatile fatty acids, and lactic acid. The pH values of cultures containing .25% lactose were significantly (P < .05) higher than the pH values of cultures containing .25% glucose. Lactose cultures reached their lowest pH more slowly than glucose cultures. Concentrations of unlabeled volatile fatty acids increased and lactic acid decreased during incubation of the cultures. Radiolabeled sugars and lactic acid were more readily metabolized to volatile fatty acids in media containing lactose than in media containing glucose. The preferred metabolism of [14C]substrates, independent of media carbohydrate, was in the following order: lactic acid > galactose, lactose > glucose. The volatile fatty acids in which radiolabel was most concentrated were acetic acid, propionic acid, or butyric acid.

External concentration of organic acid anions and pH: key independent variables for studying how organic acids inhibit growth of bacteria in mildly acidic foods.

PubMed

Carpenter, C E; Broadbent, J R

2009-01-01

Although the mechanisms by which organic acids inhibit growth of bacteria in mildly acidic foods are not fully understood, it is clear that intracellular accumulation of anions is a primary contributor to inhibition of bacterial growth. We hypothesize that intracellular accumulation of anions is driven by 2 factors, external anion concentration and external acidity. This hypothesis follows from basic chemistry principles that heretofore have not been fully applied to studies in the field, and it has led us to develop a novel approach for predicting internal anion concentration by controlling the external concentration of anions and pH. This approach overcomes critical flaws in contemporary experimental design that invariably target concentration of either protonated acid or total acid in the growth media thereby leaving anion concentration to vary depending on the pK(a) of the acids involved. Failure to control external concentration of anions has undoubtedly confounded results, and it has likely led to misleading conclusions regarding the antimicrobial action of organic acids. In summary, we advocate an approach for directing internal anion levels by controlling external concentration of anions and pH because it presents an additional opportunity to study the mechanisms by which organic acids inhibit bacterial growth. Knowledge gained from such studies would have important application in the control of important foodborne pathogens such as Listeria monocytogenes, and may also facilitate efforts to promote the survival in foods or beverages of desirable probiotic bacteria.

Usnic Acid, a Natural Antimicrobial Agent Able To Inhibit Bacterial Biofilm Formation on Polymer Surfaces

PubMed Central

Francolini, I.; Norris, P.; Piozzi, A.; Donelli, G.; Stoodley, P.

2004-01-01

In modern medicine, artificial devices are used for repair or replacement of damaged parts of the body, delivery of drugs, and monitoring the status of critically ill patients. However, artificial surfaces are often susceptible to colonization by bacteria and fungi. Once microorganisms have adhered to the surface, they can form biofilms, resulting in highly resistant local or systemic infections. At this time, the evidence suggests that (+)-usnic acid, a secondary lichen metabolite, possesses antimicrobial activity against a number of planktonic gram-positive bacteria, including Staphylococcus aureus, Enterococcus faecalis, and Enterococcus faecium. Since lichens are surface-attached communities that produce antibiotics, including usnic acid, to protect themselves from colonization by other bacteria, we hypothesized that the mode of action of usnic acid may be utilized in the control of medical biofilms. We loaded (+)-usnic acid into modified polyurethane and quantitatively assessed the capacity of (+)-usnic acid to control biofilm formation by either S. aureus or Pseudomonas aeruginosa under laminar flow conditions by using image analysis. (+)-Usnic acid-loaded polymers did not inhibit the initial attachment of S. aureus cells, but killing the attached cells resulted in the inhibition of biofilm. Interestingly, although P. aeruginosa biofilms did form on the surface of (+)-usnic acid-loaded polymer, the morphology of the biofilm was altered, possibly indicating that (+)-usnic acid interfered with signaling pathways. PMID:15504865

Degradation of spent craft brewer's yeast by caprine rumen hyper ammonia-producing bacteria.

PubMed

Harlow, B E; Bryant, R W; Cohen, S D; O'Connell, S P; Flythe, M D

2016-10-01

Spent yeast from craft beers often includes more hops (Humulus lupulus L.) secondary metabolites than traditional recipes. These compounds include α- and β- acids, which are antimicrobial to the rumen hyper ammonia-producing bacteria (HAB) that are major contributors to amino acid degradation. The objective was to determine if the hops acids in spent craft brewer's yeast (CY; ~ 3·5 mg g(-1) hops acids) would protect it from degradation by caprine rumen bacteria and HAB when compared to a baker's yeast (BY; no hops acids). Cell suspensions were prepared by harvesting rumen fluid from fistulated goats, straining and differential centrifugation. The cells were re-suspended in media with BY or CY. After 24 h (39°C), HAB were enumerated and ammonia was measured. Fewer HAB and less ammonia was produced from CY than from BY. Pure culture experiments were conducted with Peptostreptococcus anaerobiusBG1 (caprine HAB). Ammonia production by BG1 from BY was greater than from CY. Ammonia production was greater when exogenous amino acids were included, but similar inhibition was observed in CY treatments. These results indicate that rumen micro-organisms deaminated the amino acids in CY to a lesser degree than BY. Spent brewer's yeast has long been included in ruminant diets as a protein supplement. However, modern craft beers often include more hops (Humulus lupulus L.) than traditional recipes. These compounds include α- and β- acids, which are antimicrobial to the rumen hyper ammonia-producing bacteria (HAB) that are major contributors to amino acid degradation. This study demonstrated that hops acids in spent craft brewer's yeast protected protein from destruction by HABin vitro. These results suggest that the spent yeast from craft breweries, a source of beneficial hops secondary metabolites, could have value as rumen-protected protein. Published 2016. This article is a U.S. Government work and is in the public domain in the USA.

Coping with low pH: molecular strategies in neutralophilic bacteria.

PubMed

Lund, Peter; Tramonti, Angela; De Biase, Daniela

2014-11-01

As part of their life cycle, neutralophilic bacteria are often exposed to varying environmental stresses, among which fluctuations in pH are the most frequent. In particular, acid environments can be encountered in many situations from fermented food to the gastric compartment of the animal host. Herein, we review the current knowledge of the molecular mechanisms adopted by a range of Gram-positive and Gram-negative bacteria, mostly those affecting human health, for coping with acid stress. Because organic and inorganic acids have deleterious effects on the activity of the biological macromolecules to the point of significantly reducing growth and even threatening their viability, it is not unexpected that neutralophilic bacteria have evolved a number of different protective mechanisms, which provide them with an advantage in otherwise life-threatening conditions. The overall logic of these is to protect the cell from the deleterious effects of a harmful level of protons. Among the most favoured mechanisms are the pumping out of protons, production of ammonia and proton-consuming decarboxylation reactions, as well as modifications of the lipid content in the membrane. Several examples are provided to describe mechanisms adopted to sense the external acidic pH. Particular attention is paid to Escherichia coli extreme acid resistance mechanisms, the activity of which ensure survival and may be directly linked to virulence. © 2014 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.

Synthesis and antimicrobial activities of new higher amino acid Schiff base derivatives of 6-aminopenicillanic acid and 7-aminocephalosporanic acid

NASA Astrophysics Data System (ADS)

Özdemir (nee Güngör), Özlem; Gürkan, Perihan; Özçelik, Berrin; Oyardı, Özlem

2016-02-01

Novel β-lactam derivatives (1c-3c) (1d-3d) were produced by using 6-aminopenicillanic acid (6-APA), 7-aminocephalosporanic acid (7-ACA) and the higher amino acid Schiff bases. The synthesized compounds were characterized by elemental analysis, IR, 1H/13C NMR and UV-vis spectra. Antibacterial activities of all the higher amino acid Schiff bases (1a-3a) (1b-3b) and β-lactam derivatives were screened against three gram negative bacteria (Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853, Acinetobacter baumannii RSKK 02026), three gram positive bacteria (Staphylococcus aureus ATCC 25923, Enterococcus faecalis ATCC 07005, Bacillus subtilis ATCC 6633) and their drug-resistant isolates by using broth microdilution method. Two fungi (Candida albicans and Candida krusei) were used for antifungal activity.

Antigenotoxic properties of lactic acid bacteria in the S. typhimurium mutagenicity assay.

PubMed

Pool-Zobel, B L; Münzner, R; Holzapfel, W H

1993-01-01

A high percentage of human tumors is reported to be related to dietary habits. One way to improve the nutritional impact is to increase the intake of protective factors, such as inhibitors of DNA damage and other types of anticarcinogens. Specific strains of lactic acid bacteria used to ferment milk are promising candidates that may be antimutagenic and anticarcinogenic. We have studied the antimutagenicity of 10 isolated strains of beneficial lactic acid bacteria. Four types of fermented milk products were also studied for their protective properties. The effect of these bacteria on the yield of revertants induced by nitrosated beef extract was investigated in the Salmonella typhimurium mutagenicity assay. Eight of 10 isolated Lactobacillus strains reduced the yield of his+ revertants almost back to the levels of the untreated controls. Different fermented fresh yogurts containing viable bacteria (probably Lactobacillus delbrueckii ssp. bulgaricus and Streptococcus thermophilus or Lactobacillus acidophilus and Bifidobacteria) showed protective effects as well. The degree of suppressing revertants was independent of the yogurt's fat content. In contrast, yogurt products that had been heat treated were not inhibitory. The other fresh fermented milk products (e.g., buttermilk, kefir, and "Dickmilch") were not antimutagenic in this study. The results imply that some bacteria used in milk processing have an antimutagenic potential and that this property is specific for the bacterial strain.

Mutant E. coli strain with increased succinic acid production

DOEpatents

Donnelly, M.; Millard, C.S.; Stols, L.

1998-06-23

A method for isolating succinic acid producing bacteria is provided comprising increasing the biomass of an organism which lacks the ability to catabolize pyruvate, and then subjecting the biomass to glucose-rich medium in an anaerobic environment to enable pyruvate-catabolizing mutants to grow. The invention also provides for a mutant that produces high amounts of succinic acid, which as been derived from a parent which lacked the genes for pyruvate formate lyase and lactate dehydrogenase, and which belongs to the E.coli Group of Bacteria. 2 figs.

Impact of lactate on growth of cultures of cecal bacteria from commercial broilers

USDA-ARS?s Scientific Manuscript database

Cultures of beneficial bacteria used in probiotics produce and utilize organic acids that may play a role in the ability of the cultures to inhibit colonization of poultry by enteropathogens. Cecal contents of adult poultry contain many of these beneficial bacteria, and earlier experiments showed th...

Transformation of gram positive bacteria by sonoporation

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

Yang, Yunfeng; Li, Yongchao

The present invention provides a sonoporation-based method that can be universally applied for delivery of compounds into Gram positive bacteria. Gram positive bacteria which can be transformed by sonoporation include, for example, Bacillus, Streptococcus, Acetobacterium, and Clostridium. Compounds which can be delivered into Gram positive bacteria via sonoporation include nucleic acids (DNA or RNA), proteins, lipids, carbohydrates, viruses, small organic and inorganic molecules, and nano-particles.

Acne

MedlinePlus

... may contain benzoyl peroxide, sulfur, resorcinol, adapalene, or salicylic acid. They work by killing bacteria, drying up skin ... Prescription formulas of benzoyl peroxide, sulfur, resorcinol, or salicylic acid Topical azelaic acid For women whose acne is ...

Contribution of gut bacteria to the metabolism of cyanidin 3-glucoside in human microbiota-associated rats.

PubMed

Hanske, Laura; Engst, Wolfram; Loh, Gunnar; Sczesny, Silke; Blaut, Michael; Braune, Annett

2013-04-28

Cyanidin 3-glucoside (C3G) is one of the major dietary anthocyanins implicated in the prevention of chronic diseases. To evaluate the impact of human intestinal bacteria on the fate of C3G in the host, we studied the metabolism of C3G in human microbiota-associated (HMA) rats in comparison with germ-free (GF) rats. Urine and faeces of the rats were analysed for C3G and its metabolites within 48 h after the application of 92 μmol C3G/kg body weight. In addition, we tested the microbial C3G conversion in vitro by incubating C3G with human faecal slurries and selected human gut bacteria. The HMA rats excreted with faeces a three times higher percentage of unconjugated C3G products and a two times higher percentage of conjugated C3G products than the GF rats. These differences were mainly due to the increased excretion of 3,4-dihydroxybenzoic acid, 2,4,6-trihydroxybenzaldehyde and 2,4,6-trihydroxybenzoic acid. Only the urine of HMA rats contained peonidin and 3-hydroxycinnamic acid and the percentage of conjugated C3G products in the urine was decreased compared with the GF rats. Overall, the presence of intestinal microbiota resulted in a 3·7% recovery of the C3G dose in HMA rats compared with 1·7% in GF rats. Human intestinal bacteria rapidly degraded C3G in vitro. Most of the C3G products were also found in the absence of bacteria, but at considerably lower levels. The higher concentrations of phenolic acids observed in the presence of intestinal bacteria may contribute to the proposed beneficial health effects of C3G.

Effects of Psychrotrophic Bacteria, Serratia liquefaciens and Acinetobacter genomospecies 10 on Yogurt Quality

PubMed Central

Shin, Yong Kook; Oh, Nam Su; Lee, Hyun Ah; Choi, Jong-Woo

2014-01-01

The aim of this study was to evaluate the effect of proteolytic (Serratia liquefaciens, match %: 99.39) or lipolytic (Acinetobacter genomospecies 10, match %: 99.90) psychrotrophic bacteria (bacterial counts, analysis of free fatty acids (FFA) and analysis of free amino acids) on the microbial and chemical properties (yogurt composition), and sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) of yogurt during storage. Yogurts were prepared with raw milk preinoculated with each psychrotrophic bacteria. The total solid, fat, and protein content were not affected by preinoculation, but the pH of yogurt preinoculated with psychrotrophic bacteria was higher than in control. There was a dramatic increase in short chain free fatty acids among FFA in yogurt with Acinetobacter genomospecies 10. For 14 d of cold storage condition, SCFFA was 25.3 mg/kg to 34.4 mg/kg (1.36 times increased), MCFFA was 20.4 mg/kg to 25.7 mg/kg (1.26 times increased), and LCFFA was 240.2 mg/kg to 322.8 mg/kg (1.34 times increased). Serratia liquefaciens (match %: 99.39) in yogurt caused a greater accumulation of free amino acids (FAA), especially bitter peptides such as leucine, valine, arginine, and tyrosine, but SDS-PAGE showed that the inoculation of Serratia liquefaciens did not affect the degree of casein degradation during storage. Taken together, the excessive peptides and FFA in yogurt generated from psychrotrophic bacteria could develop off-flavors that degrade the quality of commercial yogurt products. PMID:26761293

Emerging Role of D-Amino Acid Metabolism in the Innate Defense

PubMed Central

Sasabe, Jumpei; Suzuki, Masataka

2018-01-01

Mammalian innate and adaptive immune systems use the pattern recognition receptors, such as toll-like receptors, to detect conserved bacterial and viral components. Bacteria synthesize diverse D-amino acids while eukaryotes and archaea generally produce two D-amino acids, raising the possibility that many of bacterial D-amino acids are bacteria-specific metabolites. Although D-amino acids have not been identified to bind to any known pattern recognition receptors, D-amino acids are enantioselectively recognized by some other receptors and enzymes including a flavoenzyme D-amino acid oxidase (DAO) in mammals. At host–microbe interfaces in the neutrophils and intestinal mucosa, DAO catalyzes oxidation of bacterial D-amino acids, such as D-alanine, and generates H2O2, which is linked to antimicrobial activity. Intestinal DAO also modifies the composition of microbiota through modulation of growth for some bacteria that are dependent on host nutrition. Furthermore, regulation and recognition of D-amino acids in mammals have additional meanings at various host–microbe interfaces; D-phenylalanine and D-tryptophan regulate chemotaxis of neutrophils through a G-coupled protein receptor, D-serine has a bacteriostatic role in the urinary tract, D-phenylalanine and D-leucine inhibit innate immunity through the sweet taste receptor in the upper airway, and D-tryptophan modulates immune tolerance in the lower airway. This mini-review highlights recent evidence supporting the hypothesis that D-amino acids are utilized as inter-kingdom communication at host–microbe interface to modulate bacterial colonization and host defense. PMID:29867842

Emerging Role of D-Amino Acid Metabolism in the Innate Defense.

PubMed

Sasabe, Jumpei; Suzuki, Masataka

2018-01-01

Mammalian innate and adaptive immune systems use the pattern recognition receptors, such as toll-like receptors, to detect conserved bacterial and viral components. Bacteria synthesize diverse D-amino acids while eukaryotes and archaea generally produce two D-amino acids, raising the possibility that many of bacterial D-amino acids are bacteria-specific metabolites. Although D-amino acids have not been identified to bind to any known pattern recognition receptors, D-amino acids are enantioselectively recognized by some other receptors and enzymes including a flavoenzyme D-amino acid oxidase (DAO) in mammals. At host-microbe interfaces in the neutrophils and intestinal mucosa, DAO catalyzes oxidation of bacterial D-amino acids, such as D-alanine, and generates H 2 O 2 , which is linked to antimicrobial activity. Intestinal DAO also modifies the composition of microbiota through modulation of growth for some bacteria that are dependent on host nutrition. Furthermore, regulation and recognition of D-amino acids in mammals have additional meanings at various host-microbe interfaces; D-phenylalanine and D-tryptophan regulate chemotaxis of neutrophils through a G-coupled protein receptor, D-serine has a bacteriostatic role in the urinary tract, D-phenylalanine and D-leucine inhibit innate immunity through the sweet taste receptor in the upper airway, and D-tryptophan modulates immune tolerance in the lower airway. This mini-review highlights recent evidence supporting the hypothesis that D-amino acids are utilized as inter-kingdom communication at host-microbe interface to modulate bacterial colonization and host defense.

Vaginal Odor

MedlinePlus

... usually don't cause vaginal odors. Neither do yeast infections. Generally, if you have vaginal odor without ... Avoid douching. All healthy vaginas contain bacteria and yeast. The normal acidity of your vagina keeps bacteria ...

Exploring microbial succession and diversity during solid-state fermentation of Tianjin duliu mature vinegar.

PubMed

Nie, Zhiqiang; Zheng, Yu; Wang, Min; Han, Yue; Wang, Yuenan; Luo, Jianmei; Niu, Dandan

2013-11-01

Tianjin duliu mature vinegar was one of famous Chinese traditional vinegars. The unique flavor and taste of vinegar are mainly generated by the multitudinous microorganisms during fermentation. In this research, the composition and succession of microbial communities in the entire solid-state fermentation were investigated, including starter daqu and acetic acid fermentation (AAF). Molds and yeasts in daqu, including Aspergillus, Saccharomycopsis and Pichia, decreased in AAF. The bacterial compositions increased from four genera in daqu to more than 13 genera in AAF. Principal component analysis showed that Acetobacter, Gluconacetobacter, Lactobacillus and Nostoc were dominant bacteria that were correlated well with AAF process. In the early fermentation period, lactic acid bacteria (LAB) decreased while acetic acid bacteria and Nostoc increased rapidly with the accumulation of total acids. Then, the abundance and diversity of LAB increased (more than 80%), indicating that LAB had important influences on the flavor and taste of vinegar. Copyright © 2013 Elsevier Ltd. All rights reserved.

Quantitative analyses of the bacterial microbiota of rearing environment, tilapia and common carp cultured in earthen ponds and inhibitory activity of its lactic acid bacteria on fish spoilage and pathogenic bacteria.

PubMed

Kaktcham, Pierre Marie; Temgoua, Jules-Bocamdé; Ngoufack Zambou, François; Diaz-Ruiz, Gloria; Wacher, Carmen; Pérez-Chabela, María de Lourdes

2017-02-01

The present study aimed to evaluate the bacterial load of water, Nile Tilapia and common Carp intestines from earthen ponds, isolate lactic acid bacteria (LAB) and assess their antimicrobial activity against fish spoilage and pathogenic bacteria. Following enumeration and isolation of microorganisms the antimicrobial activity of the LAB isolates was evaluated. Taxonomic identification of selected antagonistic LAB strains was assessed, followed by partial characterisation of their antimicrobial metabolites. Results showed that high counts (>4 log c.f.u ml -1 or 8 log c.f.u g -1 ) of total aerobic bacteria were recorded in pond waters and fish intestines. The microbiota were also found to be dominated by Salmonella spp., Vibrio spp., Staphylococcus spp. and Escherichia coli. LAB isolates (5.60%) exhibited potent direct and extracellular antimicrobial activity against the host-derived and non host-derived spoilage and pathogenic bacteria. These antagonistic isolates were identified and Lactococcus lactis subsp. lactis was found as the predominant (42.85%) specie. The strains displayed the ability to produce lactic, acetic, butyric, propionic and valeric acids. Bacteriocin-like inhibitory substances with activity against Gram-positive and Gram-negative (Vibrio spp. and Pseudomonas aeruginosa) bacteria were produced by three L. lactis subsp. lactis strains. In this study, the LAB from the microbiota of fish and pond water showed potent antimicrobial activity against fish spoilage or pathogenic bacteria from the same host or ecological niche. The studied Cameroonian aquatic niche is an ideal source of antagonistic LAB that could be appropriate as new fish biopreservatives or disease control agents in aquaculture under tropical conditions in particular or worldwide in general.

[Studies on anaerobic infection in oro-maxillary region--rapid diagnosis by gas-liquid chromatography and antibiotic susceptibilities of anaerobic bacteria].

PubMed

Tanaka, J I

1989-08-01

Subject material for this study was pus collected from patients with purulent inflammation in the oro-maxillary region. Direct gas-liquid chromatography (GLC) analysis was made, bacterial isolation and identification were carried out, and comparisons were made with results from GLC analysis and anaerobic isolates in a PYG medium. In addition, antibiotic susceptibilities of anaerobic bacteria were examined. Results 1. Anaerobic bacteria were isolated from 85 of 100 cases of obstructive abscesses. Of the 85, 49 were cases of mixed infection involving both anaerobic and aerobic bacteria; and 64 cases were involved with more than 2 species of anaerobic bacteria. Of the 184 strains of anaerobic isolates, 53 were Bacteroides sp. and 51 were Peptostreptococcus sp. The 2 groups accounted for more than half of the isolates. 2. Group A, in which no VFA was detected, accounted for 17 out of 100 cases. Group B, in which acetic acid was detected, accounted for 20 cases; and Group C, in which butyric acid was detected, accounted for 20 cases; and Group D, in which iso-valeric acid was detected, accounted for 8 cases. Direct GLC analysis revealed iso-caproic and caproic acids in the 35 cases constituting Group E. 3. Whereas the percentage of anaerobic bacteria was 64.7% in Group A and 60% in Group B, significantly higher percentages were noted in Group C (95%), Group D (100%) and Group E (100%). The following species were isolated as major member in the groups; Group A--Streptococcus intermedius, Group B--Peptostreptococcus micros, Group C--Fusobacterium nucleatum, Group D--Bacteroides gingivalis, and Group E--Peptostreptococcus anaerobius. 4. In all cases, the sum of VFA produced in the PYG medium by anaerobic isolates was classified into Group A' to E'. Ratios of agreement between VFA as revealed by direct GLC and VFA as revealed by PYG.GLC were as follows: Group A-A'; 47.1%, Group B-B' and C-C'; 45%, Group D-D'; 87.5%, and Group E-E'; 62.9%. 5. In Group B, no propionic acid was detected. The 2 cases in which acetic acid occurred in a concentration greater than 14 x 10(-4) meq/ml belonged to Group B'. In Group C, no isobutyric acid was detected; and the 5 cases in which butyric acid was detected in a concentration of more than 7 x 10(-4) meq/ml belonged to Group C'. Varelic acid was not detected in Group D; and 7 out of the 8 cases in which iso-valeric acid, irrespective of concentration, was detected belonged to Group D'.(ABSTRACT TRUNCATED AT 400 WORDS)

Characterization of Lactic Acid Bacteria Isolated from Sauce-type Kimchi.

PubMed

Jung, Suk Hee; Park, Joung Whan; Cho, Il Jae; Lee, Nam Keun; Yeo, In-Cheol; Kim, Byung Yong; Kim, Hye Kyung; Hahm, Young Tae

2012-09-01

This study was carried out to investigate the isolation and characterization of lactic acid bacteria (LAB) from naturally fermented sauce-type kimchi. Sauce-type kimchi was prepared with fresh, chopped ingredients (Korean cabbage, radish, garlic, ginger, green onion, and red pepper). The two isolated bacteria from sauce-type kimchi were identified as Pediococcus pentosaceus and Lactobacillus brevis by 16S rDNA sequencing and tentatively named Pediococcus sp. IJ-K1 and Lactobacillus sp. IJ-K2, respectively. Pediococcus sp. IJ-K1 was isolated from the early and middle fermentation stages of sauce-type kimchi whereas Lactobacillus sp. IJ-K2 was isolated from the late fermentation stage. The resistance of Pediococcus sp. IJ-K1 and Lactobacillus sp. IJ-K2 to artificial gastric and bile acids led to bacterial survival rates that were 100% and 84.21%, respectively.

Butanol is cytotoxic to Lactococcus lactis while ethanol and hexanol are cytostatic.

PubMed

Hviid, Anne-Mette Meisner; Ruhdal-Jensen, Peter; Kilstrup, Mogens

2017-04-01

Lactic acid bacteria currently used extensively by the dairy industry have a superior tolerance towards short-chain alcohols, which makes them interesting targets for use in future bio-refineries. The mechanism underlying the alcohol tolerance of lactic acid bacteria has so far received little attention. In the present study, the physiological alcohol stress response of Lactococcus lactis subsp. cremoris MG1363 towards the primary, even-chain alcohols ethanol, butanol and hexanol, was characterized. The alcohol tolerance of L. lactis was found to be comparable to those reported for highly alcohol-resistant lactic acid bacteria. Combined results from alcohol survival rate, live/dead staining, and a novel usage of the β-galactosidase assay, revealed that while high concentrations of ethanol and hexanol were cytostatic to L. lactis, high concentrations of butanol were cytotoxic, causing irreparable damages to the cell membrane.

Practical applications of sulfate-reducing bacteria to control acid mine drainage at the Lilly/Orphan Boy Mine near Elliston, Montana

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

Canty, M.

The overall purpose of this document is to provide a detailed technical description of a technology, biological sulfate reduction, which is being demonstrated under the Mine Waste Technology Pilot Program, and provide the technology evaluation process undertaken to select this technology for demonstration. In addition, this document will link the use of the selected technology to an application at a specific site. The purpose of this project is to develop technical information on the ability of biological sulfate reduction to slow the process of acid generation and, thus, improve water quality at a remote mine site. Several technologies are screenedmore » for their potential to treat acid mine water and to function as a source control for a specific acid-generating situation: a mine shaft and associated underground workings flooded with acid mine water and discharging a small flow from a mine opening. The preferred technology is the use of biological sulfate reduction. Sulfate-reducing bacteria are capable of reducing sulfate to sulfide, as well as increasing the pH and alkalinity of water affected by acid generation. Soluble sulfide reacts with the soluble metals in solution to form insoluble metal sulfides. The environment needed for efficient sulfate-reducing bacteria growth decreases acid production by reducing the dissolved oxygen in water and increasing pH. A detailed technical description of the sulfate-reducing bacteria technology, based on an extensive review of the technical literature, is presented. The field demonstration of this technology to be performed at the Lilly/Orphan Boy Mine is also described. Finally, additional in situ applications of biological sulfate reduction are presented.« less

High-volume extraction of nucleic acids by magnetic bead technology for ultrasensitive detection of bacteria in blood components.

PubMed

Störmer, Melanie; Kleesiek, Knut; Dreier, Jens

2007-01-01

Nucleic acid isolation, the most technically demanding and laborious procedure performed in molecular diagnostics, harbors the potential for improvements in automation. A recent development is the use of magnetic beads covered with nucleic acid-binding matrices. We adapted this technology with a broad-range 23S rRNA real-time reverse transcription (RT)-PCR assay for fast and sensitive detection of bacterial contamination of blood products. We investigated different protocols for an automated high-volume extraction method based on magnetic-separation technology for the extraction of bacterial nucleic acids from platelet concentrates (PCs). We added 2 model bacteria, Staphylococcus epidermidis and Escherichia coli, to a single pool of apheresis-derived, single-donor platelets and assayed the PCs by real-time RT-PCR analysis with an improved primer-probe system and locked nucleic acid technology. Co-amplification of human beta(2)-microglobulin mRNA served as an internal control (IC). We used probit analysis to calculate the minimum concentration of bacteria that would be detected with 95% confidence. For automated magnetic bead-based extraction technology with the real-time RT-PCR, the 95% detection limit was 29 x 10(3) colony-forming units (CFU)/L for S. epidermidis and 22 x 10(3) CFU/L for E. coli. No false-positive results occurred, either due to nucleic acid contamination of reagents or externally during testing of 1030 PCs. High-volume nucleic acid extraction improved the detection limit of the assay. The improvement of the primer-probe system and the integration of an IC make the RT-PCR assay appropriate for bacteria screening of platelets.

Conversion of (Meth)acrylic acids to methane granular sludge: Initiation by specific anerobic microflora

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

Shtarkman, N.B.; Obraztova, A.Y.; Laurinavichyus, K.S.

1995-03-01

The role of a specific anaerobic microflora in the initiation of degradation of (meth)acrylic acids to methane by granular sludge from a UASB reactor was investigated. Associations of anaerobic bacteria isolated from the anaerobic sludge, which was used for a long time for treatment of wastewater from (meth)acrylate production, were able to realize the initial stage of (meth)acrylic acid decomposition, i.e., a conversion of acrylic and methacrylic acids to propionic and isobutyric acids, respectively. When added to granules, these association played a role of an {open_quotes}initiator{close_quotes} of the degradation process, which was then continued by the granular sludge microflora utilizingmore » propionate and isobutyrate. Some characteristics of the granules adapted to propionate or isobutyrate are presented. The rates of propionate and isobutyrate consumption by adapted granules is, respectively, 21 and 53 times higher than the values obtained for nonadapted granules. A combined use of {open_quotes}initiating{close_quotes} bacteria and adapted granules provided degradation of (meth)acrylic acids with a maximum methane yield. The possibility is discussed of employing the granules, which are adapted to short-chain fatty acids, and the {open_quotes}initiating{close_quotes} bacteria, which accomplish the initial steps of the organic material decomposition to lower fatty acids, for the conversion of various chemical compounds to methane. 10 refs., 3 figs., 2 tabs.« less

Isolation of acetic, propionic and butyric acid-forming bacteria from biogas plants.

PubMed

Cibis, Katharina Gabriela; Gneipel, Armin; König, Helmut

2016-02-20

In this study, acetic, propionic and butyric acid-forming bacteria were isolated from thermophilic and mesophilic biogas plants (BGP) located in Germany. The fermenters were fed with maize silage and cattle or swine manure. Furthermore, pressurized laboratory fermenters digesting maize silage were sampled. Enrichment cultures for the isolation of acid-forming bacteria were grown in minimal medium supplemented with one of the following carbon sources: Na(+)-dl-lactate, succinate, ethanol, glycerol, glucose or a mixture of amino acids. These substrates could be converted by the isolates to acetic, propionic or butyric acid. In total, 49 isolates were obtained, which belonged to the phyla Firmicutes, Tenericutes or Thermotogae. According to 16S rRNA gene sequences, most isolates were related to Clostridium sporosphaeroides, Defluviitoga tunisiensis and Dendrosporobacter quercicolus. Acetic, propionic or butyric acid were produced in cultures of isolates affiliated to Bacillus thermoamylovorans, Clostridium aminovalericum, Clostridium cochlearium/Clostridium tetani, C. sporosphaeroides, D. quercicolus, Proteiniborus ethanoligenes, Selenomonas bovis and Tepidanaerobacter sp. Isolates related to Thermoanaerobacterium thermosaccharolyticum produced acetic, butyric and lactic acid, and isolates related to D. tunisiensis formed acetic acid. Specific primer sets targeting 16S rRNA gene sequences were designed and used for real-time quantitative PCR (qPCR). The isolates were physiologically characterized and their role in BGP discussed. Copyright © 2016 Elsevier B.V. All rights reserved.

The activity of ferulic and gallic acids in biofilm prevention and control of pathogenic bacteria.

PubMed

Borges, Anabela; Saavedra, Maria J; Simões, Manuel

2012-01-01

The activity of two phenolic acids, gallic acid (GA) and ferulic acid (FA) at 1000 μg ml(-1), was evaluated on the prevention and control of biofilms formed by Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus and Listeria monocytogenes. In addition, the effect of the two phenolic acids was tested on planktonic cell susceptibility, bacterial motility and adhesion. Biofilm prevention and control were tested using a microtiter plate assay and the effect of the phenolic acids was assessed on biofilm mass (crystal violet staining) and on the quantification of metabolic activity (alamar blue assay). The minimum bactericidal concentration for P. aeruginosa was 500 μg ml(-1) (for both phenolic acids), whilst for E. coli it was 2500 μg ml(-1) (FA) and 5000 μg ml(-1) (GA), for L. monocytogenes it was >5000 μg ml(-1) (for both phenolic acids), and for S. aureus it was 5000 μg ml(-1) (FA) and >5000 μg ml(-1) (GA). GA caused total inhibition of swimming (L. monocytogenes) and swarming (L. monocytogenes and E. coli) motilities. FA caused total inhibition of swimming (L. monocytogenes) and swarming (L. monocytogenes and E. coli) motilities. Colony spreading of S. aureus was completely inhibited by FA. The interference of GA and FA with bacterial adhesion was evaluated by the determination of the free energy of adhesion. Adhesion was less favorable when the bacteria were exposed to GA (P. aeruginosa, S. aureus and L. monocytogenes) and FA (P. aeruginosa and S. aureus). Both phenolics had preventive action on biofilm formation and showed a higher potential to reduce the mass of biofilms formed by the Gram-negative bacteria. GA and FA promoted reductions in biofilm activity >70% for all the biofilms tested. The two phenolic acids demonstrated the potential to inhibit bacterial motility and to prevent and control biofilms of four important human pathogenic bacteria. This study also emphasizes the potential of phytochemicals as an emergent source of biofilm control products.

Attachment of 13 Types of Foodborne Bacteria to Jalapeño and Serrano Peppers and Antibacterial Effect of Roselle Calyx Extracts, Sodium Hypochlorite, Colloidal Silver, and Acetic Acid against These Foodborne Bacteria on Peppers.

PubMed

Rangel-Vargas, Esmeralda; Gómez-Aldapa, Carlos A; Falfan-Cortes, Reyna N; Rodríguez-Marín, María L; Godínez-Oviedo, Angélica; Acevedo-Sandoval, Otilio A; Castro-Rosas, Javier

2017-03-01

Chili peppers are a very important crop in Mexico. However, these peppers have been associated with Salmonella infection outbreaks in the United States, and Salmonella and diarrheagenic Escherichia coli pathotypes have been isolated from jalapeño and serrano peppers in Mexico. To decrease microbial contamination of fruits and vegetables, chemical agents are commonly used; however, chemical agents used to eliminate pathogenic bacteria on vegetables have a limited antimicrobial effect. Roselle ( Hibiscus sabdariffa ) calyces have been reported to have an antimicrobial effect on pathogenic bacteria. In the present study, the antibacterial effect of four roselle calyx extracts (water, methanol, acetone, and ethyl acetate), sodium hypochlorite, colloidal silver, and acetic acid against foodborne bacteria was evaluated on contaminated jalapeño and serrano peppers. The 13 types of foodborne bacteria evaluated were Listeria monocytogenes , Shigella flexneri , Salmonella Typhimurium, Salmonella Typhi, Salmonella Montevideo, Staphylococcus aureus , E. coli O157:H7, five E. coli pathotypes (Shiga toxin producing, enteropathogenic, enterotoxigenic, enteroinvasive, and enteroaggregative), and Vibrio cholerae O1. All 13 types attached to both pepper types, with no significant differences in attachment between jalapeño and serrano peppers. Roselle calyx extract treatment resulted in a greater reduction in levels of all foodborne bacteria than did treatment with sodium hypochlorite, colloidal silver, and acetic acid on both pepper types. Roselle calyx extracts may be a useful for disinfection of chili peppers in the field, processing plants, restaurants, and homes.

Antimicrobial and enhancement of the antibiotic activity by phenolic compounds: Gallic acid, caffeic acid and pyrogallol.

PubMed

Lima, Valéria N; Oliveira-Tintino, Cícera D M; Santos, Enaide S; Morais, Luís P; Tintino, Saulo R; Freitas, Thiago S; Geraldo, Yuri S; Pereira, Raimundo L S; Cruz, Rafael P; Menezes, Irwin R A; Coutinho, Henrique D M

2016-10-01

The indiscriminate use of antimicrobial drugs has increased the spectrum of exposure of these organisms. In our studies, these phenolic compounds were evaluated: gallic acid, caffeic acid and pyrogallol. The antibacterial, antifungal and modulatory of antibiotic activities of these compounds were assayed using microdilution method of Minimum Inhibitory Concentration (MIC) to bacteria and Minimum Fungicide Concentration (MFC) to fungi. The modulation was made by comparisons of the MIC and MFC of the compounds alone and combined with drugs against bacteria and fungi respectively, using a sub-inhibitory concentration of 128 μg/mL of substances (MIC/8). All substances not demonstrated clinically relevant antibacterial activity with a MIC above ≥1024 μg/mL. As a result, we observed that the caffeic acid presented a potentiating antibacterial effect over the 3 groups of bacteria studied. Pyrogallol showed a synergistic effect with two of the antibiotics tested, but only against Staphylococcus aureus. In general, caffeic acid was the substance that presented with the greatest number of antibiotics and with the greatest number of bacteria. In relation to the antifungal activity of all the compounds, the verified results were ≥1024 μg/mL, not demonstrating significant activity. Regarding potentiation of the effect of fluconazole, was observed synergistic effect only when assayed against Candida tropicalis, with all substances. Therefore, as can be seen, the compounds presented as substances that can be promising potentiating agents of antimicrobial drugs, even though they do not have direct antibacterial and antifungal action. Copyright © 2016 Elsevier Ltd. All rights reserved.

Identification and Characterization of Lactic Acid Bacteria in a Commercial Probiotic Culture

PubMed Central

MENCONI, Anita; KALLAPURA, Gopala; LATORRE, Juan D.; MORGAN, Marion J.; PUMFORD, Neil R.; HARGIS, Billy M.; TELLEZ, Guillermo

2014-01-01

The aim of the present study was to describe the identification and characterization (physiological properties) of two strains of lactic acid bacteria (LAB 18 and 48) present in a commercial probiotic culture, FloraMax®-B11. Isolates were characterized morphologically, and identified biochemically. In addition, the MIDI System ID, the Biolog ID System, and 16S rRNA sequence analyses for identification of LAB 18 and LAB 48 strains were used to compare the identification results. Tolerance and resistance to acidic pH, high osmotic concentration of NaCl, and bile salts were tested in broth medium. In vitro assessment of antimicrobial activity against enteropathogenic bacteria and susceptibility to antibiotics were also tested. The results obtained in this study showed tolerance of LAB 18 and LAB 48 to pH 3.0, 6.5% NaCl and a high bile salt concentration (0.6%). Both strains evaluated showed in vitro antibacterial activity against Salmonella enterica serovar Enteritidis, Escherichia coli (O157:H7), and Campylobacter jejuni. These are important characteristics of lactic acid bacteria that should be evaluated when selecting strains to be used as probiotics. Antimicrobial activity of these effective isolates may contribute to efficacy, possibly by direct antimicrobial activity in vivo. PMID:24936379

Metabolism of ferulic acid during growth of Lactobacillus plantarum and Lactobacillus collinoides.

PubMed

Knockaert, Dries; Raes, Katleen; Wille, Christophe; Struijs, Karin; Van Camp, John

2012-08-30

Food-isolated lactic acid bacteria can transform ferulic acid (FA) into several products. Since quantification of these metabolites during the different bacterial growth phases is lacking, the aim of this study was to identify and quantify conversion products of FA and to follow the kinetics of FA metabolism during growth of Lactobacillus plantarum and Lactobacillus collinoides. Lactobacillus plantarum and Lactobacillus collinoides were incubated in MRS broth, to which different amounts of FA were added (final concentrations of 0, 0.5, 1.5 and 3 mmol L⁻¹), at 30 °C until the late stationary phase. Lactobacillus plantarum metabolised FA into 4-vinylguaiacol (4-VG) and hydroferulic acid (HFA). Conversion to 4-VG started simultaneously with the degradation of FA, while formation of HFA started in the mid-exponential phase. Lactobacillus collinoides only formed 4-VG, mainly in the stationary phase. No significant effect of the different amounts of FA was seen on the growth and fermentation characteristics of both bacteria. The results demonstrate that both bacteria are able to convert FA. However, start of conversion differs between the two strains. The different amounts of FA had no influence on the growth and fermentation characteristics of both bacteria. Copyright © 2012 Society of Chemical Industry.

The role of lactic acid bacteria (Lactobacillus sp yel133) from beef in inhibiting of microbial contaminants on various fillers of starter culture

NASA Astrophysics Data System (ADS)

Yunilas; Mirwandhono, E.

2018-02-01

The role of Lactic Acid Bacteria (LAB) on the starter culture can be seen from the ability to grow and suppress the growth of microbial contaminants (fungi). The research aimed to investigate the role of LAB (Lactobacillus sp YEL133) in inhibiting microbial contaminants (fungi) on starter cultures of various fillers. The materials used in this research was Lactobacillus sp YEL133 from beef and various fillers (rice flour, corn starch and wheat flour). The research methods used completely randomized design (CRD) with 3 treatments and 4 replications. The treatments of this research was P1(rice flour), P2 (corn starch) and P3 (wheat flour) that inoculated with Lactobacillus sp YEL133. Parameters which is observed such as: growth of lactic acid bacteria, total microbes and total fungi as microbial contaminants. The results showed that the starter culture with a filler material of rice flour produce lactic acid bacteria and microbes were highly significant (P <0.01) for corn starch and wheat flour, as well as able to suppress the growth of microbial contaminants (fungi). The conclusion of the research is the use Lactobacillus sp YEL133 can suppress the growth of fungi on the starter culture using rice flour.

Molecular diversity of lactic acid bacteria on ileum broiler chicken fed by bran and bran fermentation

NASA Astrophysics Data System (ADS)

Baniyah, Laelatul; Nur Jannah, Siti; Rukmi, Isworo; Sugiharto

2018-05-01

Lactic Acid Bacteria (LAB) is a digestive tract microflora that have a positive role in poultry health. The number and diversity of LAB in the digestive tract affected by several factors, among them was the kind of feed. The purpose of this research was to know diversity of Lactic Acid Bacteria (LAB) ileum broiler’s after feeding with prebiotic bran and Rhizopus oryzae fermented bran which was added to commercial feed. As much as 15 broilers were used to determine the diversity of LAB. All broilers were fed using commercial feed. The control used commercial feed no addition of bran or fermented bran, and commercial feed with fermented bran and nonfermented bran were as a treatment. To determine the diversity of LAB, T-RFLP method was applied. The Hae III and Msp I were used as restriction enzymes. The number of phylotype, relative abundance, Shannon diversity index (H '), evenness (E), and Dominance (D) were examined. The results indicated that the addition of prebiotic bran on commercial feed showed a higher diversity of lactic acid bacteria on broiler’s ileum, compared with control and addition of Rhizopus oryzae fermented bran. LAB group that dominates in the ileum is Lactobacillus sp. and L. delbruecii subs bulgaricus.

Tooth decay -- early childhood

MedlinePlus

... in your child's mouth. Sugar feeds the natural forming bacteria in your child's mouth. Bacteria produce acid. ... MO: Elsevier; 2016:chap 7. Martin B, Baumhardt H, D'Alesio A, Woods K. Oral disorders. In: ...

Tyramine and phenylethylamine biosynthesis by food bacteria.

PubMed

Marcobal, Angela; De las Rivas, Blanca; Landete, José María; Tabera, Laura; Muñoz, Rosario

2012-01-01

Tyramine poisoning is caused by the ingestion of food containing high levels of tyramine, a biogenic amine. Any foods containing free tyrosine are subject to tyramine formation if poor sanitation and low quality foods are used or if the food is subject to temperature abuse or extended storage time. Tyramine is generated by decarboxylation of the tyrosine through tyrosine decarboxylase (TDC) enzymes derived from the bacteria present in the food. Bacterial TDC have been only unequivocally identified and characterized in Gram-positive bacteria, especially in lactic acid bacteria. Pyridoxal phosphate (PLP)-dependent TDC encoding genes (tyrDC) appeared flanked by a similar genetic organization in several species of lactic acid bacteria, suggesting a common origin by a single mobile genetic element. Bacterial TDC are also able to decarboxylate phenylalanine to produce phenylethylamine (PEA), another biogenic amine. The molecular knowledge of the genes involved in tyramine production has led to the development of molecular methods for the detection of bacteria able to produce tyramine and PEA. These rapid and simple methods could be used for the analysis of the ability to form tyramine by bacteria in order to evaluate the potential risk of tyramine biosynthesis in food products.

Helicobacter pylori Containing Only Cytoplasmic Urease Is Susceptible to Acid

PubMed Central

Krishnamurthy, Partha; Parlow, Mary; Zitzer, Jason B.; Vakil, Nimish B.; Mobley, Harry L. T.; Levy, Marilyn; Phadnis, Suhas H.; Dunn, Bruce E.

1998-01-01

Helicobacter pylori, an important etiologic agent in a variety of gastroduodenal diseases, produces large amounts of urease as an essential colonization factor. We have demonstrated previously that urease is located within the cytoplasm and on the surface of H. pylori both in vivo and in stationary-phase culture. The purpose of the present study was to assess the relative contributions of cytoplasmic and surface-localized urease to the ability of H. pylori to survive exposure to acid in the presence of urea. Toward this end, we compared the acid resistance in vitro of H. pylori cells which possessed only cytoplasmic urease to that of bacteria which possessed both cytoplasmic and surface-localized or extracellular urease. Bacteria with only cytoplasmic urease activity were generated by using freshly subcultured bacteria or by treating repeatedly subcultured H. pylori with flurofamide (1 μM), a potent, but poorly diffusible urease inhibitor. H. pylori with cytoplasmic and surface-located urease activity survived in an acid environment when 5 mM urea was present. In contrast, H. pylori with only cytoplasmic urease shows significantly reduced survival when exposed to acid in the presence of 5 mM urea. Similarly, Escherichia coli SE5000 expressing H. pylori urease and the Ni2+ transport protein NixA, which expresses cytoplasmic urease activity at levels similar to those in wild-type H. pylori, survived minimally when exposed to acid in the presence of 5 to 50 mM urea. We conclude that cytoplasmic urease activity alone is not sufficient (although cytoplasmic urease activity is likely to be necessary) to allow survival of H. pylori in acid; the activity of surface-localized urease is essential for resistance of H. pylori to acid under the assay conditions used. Therefore, the mechanism whereby urease becomes associated with the surface of H. pylori, which involves release of the enzyme from bacteria due to autolysis followed by adsorption of the enzyme to the surface of intact bacteria (“altruistic autolysis”), is essential for survival of H. pylori in an acid environment. The ability of H. pylori to survive exposure to low pH is likely to depend on a combination of both cytoplasmic and surface-associated urease activities. PMID:9784504

Chemical composition and antimicrobial activity of fatty acid methyl ester of Quercus leucotrichophora fruits.

PubMed

Sati, Ankita; Sati, Sushil Chandra; Sati, Nitin; Sati, O P

2017-03-01

Natural fats and dietary oils are chief source of fatty acids and are well known to have antimicrobial activities against various microbes. The chemical composition and antimicrobial activities of fatty acids from fruits of white Oak (Quercus leucotrichophora) are yet unexplored and therefore the present study for the first time determines the fatty acid composition, and the antibacterial and antifungal activities of fatty acid methyl esters (FAME) of the white Oak plant found along the Himalayan region of Uttarakhand, India. The GCMS analysis revealed the presence of higher amount of saturated fatty acids than unsaturated fatty acids. FAME extract of fruits of Q. leucotrichophora demonstrated better antibacterial activity against Gram-positive bacteria than the Gram-negative bacteria. The present studies clearly establish the potential of the fruits of Q. leucotrichophora for use in soap, cosmetics and pharmaceutical industries.

Antifungal activity of Leuconostoc citreum and Weissella confusa in rice cakes.

PubMed

Baek, Eunjong; Kim, Hyojin; Choi, Hyejung; Yoon, Sun; Kim, Jeongho

2012-10-01

The antifungal activity of organic acids greatly improves the shelf life of bread and bakery products. However, little is known about the effect of lactic acid fermentation on fungal contamination in rice cakes. Here, we show that lactic acid fermentation in rice dough can greatly retard the growth of three fungal species when present in rice cakes, namely Cladosporium sp. YS1, Neurospora sp. YS3, and Penicillium crustosum YS2. The antifungal activity of the lactic acid bacteria against these fungi was much better than that of 0.3% calcium propionate. We found that organic acids including lactic and acetic acid, which are byproducts of lactic fermentation or can be artificially added, were the main antifungal substances. We also found that some Leuconostoc citreum and Weissella confusa strains could be good starter species for rice dough fermentation. These results imply that these lactic acid bacteria can be applicable to improve the preservation of rice cakes.

Analysis of fatty acid composition of sea cucumber Apostichopus japonicus using multivariate statistics

NASA Astrophysics Data System (ADS)

Xu, Qinzeng; Gao, Fei; Xu, Qiang; Yang, Hongsheng

2014-11-01

Fatty acids (FAs) provide energy and also can be used to trace trophic relationships among organisms. Sea cucumber Apostichopus japonicus goes into a state of aestivation during warm summer months. We examined fatty acid profiles in aestivated and non-aestivated A. japonicus using multivariate analyses (PERMANOVA, MDS, ANOSIM, and SIMPER). The results indicate that the fatty acid profiles of aestivated and non-aestivated sea cucumbers differed significantly. The FAs that were produced by bacteria and brown kelp contributed the most to the differences in the fatty acid composition of aestivated and nonaestivated sea cucumbers. Aestivated sea cucumbers may synthesize FAs from heterotrophic bacteria during early aestivation, and long chain FAs such as eicosapentaenoic (EPA) and docosahexaenoic acid (DHA) that produced from intestinal degradation, are digested during deep aestivation. Specific changes in the fatty acid composition of A. japonicus during aestivation needs more detailed study in the future.

High-Throughput rRNA Gene Sequencing Reveals High
and Complex Bacterial Diversity Associated with
Brazilian Coffee Bean Fermentation

PubMed Central

Vinícius de Melo, Gilberto

2018-01-01

Summary Coffee bean fermentation is a spontaneous, on-farm process involving the action of different microbial groups, including bacteria and fungi. In this study, high-throughput sequencing approach was employed to study the diversity and dynamics of bacteria associated with Brazilian coffee bean fermentation. The total DNA from fermenting coffee samples was extracted at different time points, and the 16S rRNA gene with segments around the V4 variable region was sequenced by Illumina high-throughput platform. Using this approach, the presence of over eighty bacterial genera was determined, many of which have been detected for the first time during coffee bean fermentation, including Fructobacillus, Pseudonocardia, Pedobacter, Sphingomonas and Hymenobacter. The presence of Fructobacillus suggests an influence of these bacteria on fructose metabolism during coffee fermentation. Temporal analysis showed a strong dominance of lactic acid bacteria with over 97% of read sequences at the end of fermentation, mainly represented by the Leuconostoc and Lactococcus. Metabolism of lactic acid bacteria was associated with the high formation of lactic acid during fermentation, as determined by HPLC analysis. The results reported in this study confirm the underestimation of bacterial diversity associated with coffee fermentation. New microbial groups reported in this study may be explored as functional starter cultures for on-farm coffee processing.

Mechanistic modeling of biocorrosion caused by biofilms of sulfate reducing bacteria and acid producing bacteria.

PubMed

Xu, Dake; Li, Yingchao; Gu, Tingyue

2016-08-01

Biocorrosion is also known as microbiologically influenced corrosion (MIC). Most anaerobic MIC cases can be classified into two major types. Type I MIC involves non-oxygen oxidants such as sulfate and nitrate that require biocatalysis for their reduction in the cytoplasm of microbes such as sulfate reducing bacteria (SRB) and nitrate reducing bacteria (NRB). This means that the extracellular electrons from the oxidation of metal such as iron must be transported across cell walls into the cytoplasm. Type II MIC involves oxidants such as protons that are secreted by microbes such as acid producing bacteria (APB). The biofilms in this case supply the locally high concentrations of oxidants that are corrosive without biocatalysis. This work describes a mechanistic model that is based on the biocatalytic cathodic sulfate reduction (BCSR) theory. The model utilizes charge transfer and mass transfer concepts to describe the SRB biocorrosion process. The model also includes a mechanism to describe APB attack based on the local acidic pH at a pit bottom. A pitting prediction software package has been created based on the mechanisms. It predicts long-term pitting rates and worst-case scenarios after calibration using SRB short-term pit depth data. Various parameters can be investigated through computer simulation. Copyright © 2016 Elsevier B.V. All rights reserved.

Application of Lactic Acid Bacteria (LAB) in freshness keeping of tilapia fillets as sashimi

NASA Astrophysics Data System (ADS)

Cao, Rong; Liu, Qi; Chen, Shengjun; Yang, Xianqing; Li, Laihao

2015-08-01

Aquatic products are extremely perishable food commodities. Developing methods to keep the freshness of fish represents a major task of the fishery processing industry. Application of Lactic Acid Bacteria (LAB) as food preservative is a novel approach. In the present study, the possibility of using lactic acid bacteria in freshness keeping of tilapia fillets as sashimi was examined. Fish fillets were dipped in Lactobacillus plantarum 1.19 (obtained from China General Microbiological Culture Collection Center) suspension as LAB-treated group. Changes in K-value, APC, sensory properties and microbial flora were analyzed. Results showed that LAB treatment slowed the increase of K-value and APC in the earlier storage, and caused a smooth decrease in sensory score. Gram-negative bacteria dominated during refrigerated storage, with Pseudomonas and Aeromonas being relatively abundant. Lactobacillus plantarum 1.19 had no obvious inhibitory effect against these Gram-negatives. However, Lactobacillus plantarum 1.19 changed the composition of Gram-positive bacteria. No Micrococcus were detected and the proportion of Staphylococcus decreased in the spoiled LAB-treated samples. The period that tilapia fillets could be used as sashimi material extended from 24 h to 48 h after LAB treatment. The potential of using LAB in sashimi processing was confirmed.

[Isolation, identification and characterization of ACC deaminase-containing endophytic bacteria from halophyte Suaeda salsa].

PubMed

Teng, Songshan; Liu, Yanping; Zhao, Lei

2010-11-01

We Isolated and characterized 1-aminocyclopropane-1-carboxylate (ACC) deaminase-containing endophytic bacteria from halophyte Suaeda salsa to understand the interactions between endophytes and halophyte. ACC deaminase-containing endophytic bacteria were isolated from root, stalk and leaf of Suaeda salsa and were identified based on morphological, physiological-biochemical properties, API and 16S rRNA sequence analysis. Isolates were evaluated for their ACC deaminase, antifungal, protease activity, siderophores and phytohormones, such as indole-3-acetic acid, gibberellic acid and abscisic acid production, as well as atmospheric nitrogen fixation and phosphate solubilization. Four ACC deaminase-containing endophytic bacteria strains named as LP11, SS12, TW1 and TW2 were isolated and identified as Pseudomonas oryzihabitans, Pseudomonas sp., Pantoea agglomerans and Pseudomonas putida respectively. All the strains possessed the phosphate-solubilizing ability and could produce siderophores and phytohormones more or less. None of them could fix atmospheric nitrogen or produce protease. Only strain SS12 showed antagonism against two phytopathogenic fungi viz Fusarium oxysporum f. sp. conglutinans and F. oxysporum f. sp. cucumerinum. ACC deaminase-containing endophytic bacteria of Pseudomonas sp. and Pantoea sp. isolated from halophyte Suaeda salsa have abundant biological characteristics related to plant growth promotion, stress homeostasis regulation and biocontrol activity.

Bovicin HC5 inhibits wasteful amino acid degradation by mixed ruminal bacteria in vitro.

PubMed

Lima, Janaína R; Ribon, Andréa de O Barros; Russell, James B; Mantovani, Hilário C

2009-03-01

Streptococcus bovis HC5 produces a broad spectrum lantibiotic (bovicin HC5) that inhibits pure cultures of hyper ammonia-producing bacteria (HAB). Experiments were preformed to see if: (1) S. bovis HC5 cells could inhibit the deamination of amino acids by mixed ruminal bacteria taken directly from a cow, (2) semi-purified bovicin was as effective as S. bovis HC5 cells, and 3) semi-purified and the feed additive monensin were affecting the same types of ammonia-producing ruminal bacteria. Because purified and semi-purified bovicin HC5 was as effective as S. bovis HC5 cells, it appeared that bovicin HC5 was penetrating the cell membranes of HAB before it could be degraded by peptidases and proteinases. Mixed ruminal bacteria that were successively transferred and enriched nine times with trypticase did not become significantly more resistant to either bovicin HC5 (50 AU mL(-1)) or monensin (5 microM), and amplified rDNA restriction analysis indicated that bovicin HC5 and monensin appeared to be selecting against the same types of bacteria.

Study of Antibacterial Activity and Bacteriology of Latex from Asclepias syriaca L

PubMed Central

McCay, Steven; Mahlberg, Paul

1973-01-01

Whole and fractionated latex of Asclepias syriaca was tested for antimicrobial or growth-promoting activity with 16 genera and species of bacteria. Latex and extracted fractions (distilled water, acetic acid, sodium bicarbonate, sulfuric acid, and ethyl ether) possessed no detectable antimicrobial activity. Comparison of growth curves of selected bacteria incubated with serum and rubber fractions, as well as controls, revealed no detectable inhibition of growth, except for a slight inhibitory response to autoclaved serum. Most bacteria were capable of utilizing latex for a substrate as indicated by the increased growth rate in the exponential phase. The stationary phase was entered simultaneously by both the treated cultures and the controls. Various bacteria cultured in a litmus latex mixture yielded populations which ranged from <104 organisms/ml for Lactobacillus casei, Staphylococcus aureus and Micrococcus lysodeikticus to 1.1 × 1010 organisms/ml for Clostridium acetobutylicum. Whole latex, as well as the serum and rubber fractions, support the growth of various bacteria, but under field conditions there is no evidence for systemic infection of this type of cell by bacteria. PMID:4790590

Effects of a combination of hinokitiol (β-thujaplicin) and an organic acid mixture on ruminal fermentation in heifers fed a high-grain diet.

PubMed

Ishii, Junichiro; Omura, Hiroshi; Mitsui, Tadao; Eguchi, Norichika; Ueno, Takashi; Goto, Hisaya; Ito, Hiroshi

2012-01-01

This study evaluated the effects of hinokitiol (a natural antibacterial compound extracted from Thujopsis dolabrata var. hondai) and an organic acid mixture (citrate content 50%) on ruminal fermentation. Antibacterial properties were examined by measuring minimal inhibitory concentration. Hinokitiol at 1.56µg/mL or an organic acid mixture at 1600µg/mL inhibited Streptococcus bovis growth. The combination of 0.78µg/mL hinokitiol and 200µg/mL of an organic acid mixture also inhibited S. bovis growth. Both hinokitiol and the hinokitiol and an organic acid mixture combination showed strong antibacterial properties on Gram-positive bacteria such as S. bovis, but relatively weak antibacterial activities on Gram-negative bacteria such as Megasphaera elsdenii. Three ruminally cannulated heifers were fed a bloat-producing diet containing barley, pelleted alfalfa meal, soybean meal and salt without long-cut roughage to investigate the ruminal characteristics in vivo. Feeding to heifers a bloat-producing diet containing 7.8mg/kg hinokitiol and 0.2% of an organic acid mixture significantly decreased the increase in stable ingesta volume. Hinokitiol or an organic acid mixture did not affect ruminal volatile fatty acids, protozoa and bacteria. These results suggest that a combination of hinokitiol and an organic acid mixture might reduce frothy bloat in cattle fed high-grain diets. © 2011 The Authors. Animal Science Journal © 2011 Japanese Society of Animal Science.

Metabolism of the 18O-methoxy substituent of 3-methoxybenzoic acid and other unlabeled methoxybenzoic acids by anaerobic bacteria.

PubMed Central

DeWeerd, K A; Saxena, A; Nagle, D P; Suflita, J M

1988-01-01

O-methyl substituents of aromatic compounds can provide C1 growth substrates for facultative and strict anaerobic bacteria isolated from diverse environments. The mechanism of the bioconversion of methoxylated benzoic acids to the hydroxylated derivatives was investigated with a model substrate and cultures of one anaerobic consortium, eight strict anaerobic bacteria, and one facultative anaerobic microorganism. Using high-pressure liquid chromatography and gas chromatography-mass spectral analysis, we found that a haloaromatic dehalogenating consortium, a dehalogenating isolate from that consortium, Eubacterium limosum, and a strain of Acetobacterium woodii metabolized 3-[methoxy-18O]methoxybenzoic acid (3-anisic acid) to 3-[hydroxy-18O]hydroxybenzoic acid stoichiometrically at rates of 1.5, 3.2, 52.4, and 36.7 nmol/min per mg of protein, respectively. A different strain of Acetobacterium and strains of Syntrophococcus, Clostridium, Desulfotomaculum, Enterobacter, and an anaerobic bacterium, strain TH-001, were unable to transform this compound. The O-demethylating ability of E. limosum was induced only with appropriate methoxylated benzoates but not with D-glucose, lactate, isoleucine, or methanol. Cross-acclimation and growth experiments with E. limosum showed a rate of metabolism that was an order of magnitude slower and showed no growth with either 4-methoxysalicylic acid (2-hydroxy-4-methoxybenzoic acid) or 4-anisic acid (4-methoxybenzoic acid) when adapted to 3-anisic acid. However, A. woodii NZva-16 showed slower rates and no growth with 3- or 4-methoxysalicylic acid when adapted to 3-anisic acid in similar experiments. The results clearly indicate a methyl rather than methoxy group removal mechanism for such reactions. PMID:3389815

Antimicrobial activity and stability of protonectin with D-amino acid substitutions.

PubMed

Qiu, Shuai; Zhu, Ranran; Zhao, Yanyan; An, Xiaoping; Jia, Fengjing; Peng, Jinxiu; Ma, Zelin; Zhu, Yuanyuan; Wang, Jiayi; Su, Jinhuan; Wang, Qingjun; Wang, Hailin; Li, Yuan; Wang, Kairong; Yan, Wenjin; Wang, Rui

2017-05-01

The misuse and overuse of antibiotics result in the emergence of resistant bacteria and fungi, which make an urgent need of the new antimicrobial agents. Nowadays, antimicrobial peptides have attracted great attention of researchers. However, the low physiological stability in biological system limits the application of naturally occurring antimicrobial peptides as novel therapeutics. In the present study, we synthesized derivatives of protonectin by substituting all the amino acid residues or the cationic lysine residue with the corresponding D-amino acids. Both the D-enantiomer of protonectin (D-prt) and D-Lys-protonectin (D-Lys-prt) exhibited strong antimicrobial activity against bacteria and fungi. Moreover, D-prt showed strong stability against trypsin, chymotrypsin and the human serum, while D-Lys-prt only showed strong stability against trypsin. Circular dichroism analysis revealed that D-Lys-prt still kept typical α-helical structure in the membrane mimicking environment, while D-prt showed left hand α-helical structure. In addition, propidium iodide uptake assay and bacteria and fungi killing experiments indicated that all D-amino acid substitution or partially D-amino acid substitution analogs could disrupt the integrity of membrane and lead the cell death. In summary, these findings suggested that D-prt and D-Lys-prt might be promising candidate antibiotic agents for therapeutic application against resistant bacteria and fungi infection. Copyright © 2017 European Peptide Society and John Wiley & Sons, Ltd. Copyright © 2017 European Peptide Society and John Wiley & Sons, Ltd.

Halotolerance and survival kinetics of lactic acid bacteria isolated from jalapeño pepper (Capsicum annuum L.) fermentation.

PubMed

González-Quijano, Génesis Karendash; Dorantes-Alvarez, Lidia; Hernández-Sánchez, Humberto; Jaramillo-Flores, María Eugenia; de Jesús Perea-Flores, María; Vera-Ponce de León, Arturo; Hernández-Rodríguez, César

2014-08-01

The microbiota associated with spontaneous fermentation of vegetables in a saline substrate may represent an important group of bacteria in the food industry. In this work, the lactic acid bacteria (LAB) Weissella cibaria, Lactobacillus plantarum, Lactobacillus paraplantarum, and Leuconostoc citreum were identified by partial 16S rRNA gene sequence analysis. In addition, entophytic bacteria such as Pantoea eucalypti, Pantoea anthophila, Enterobacter cowanii, and Enterobacter asburiae were detected, but they were irrelevant for the fermentation process and were inhibited after 12 h of fermentation when the pH decreased from 6.5 to 4.9. Moreover, 2 species of yeast were isolated and identified as Hanseniaspora pseudoguilliermondii and Kodamaea ohmeri by their partial 26S rRNA gene sequence. The growth of LAB was evaluated at different sodium chloride contents. L. citreum was the most halotolerant species followed by L. plantarum and W. cibaria with a concentration index to obtain a 50% population reduction (IC(50)) of 7.2%, 6.6%, and 5.2%, respectively. Furthermore, the growth of LAB and Escherichia coli O157:H7 was evaluated in the presence of the main phenylpropanoids from chilli peppers such as p-coumaric and ferulic acid. It was determined that LAB can grow in both acids at 4 mM, unlike E. coli O157:H7, whose growth is inhibited in the presence of these acids. © 2014 Institute of Food Technologists®

Exploiting antagonistic activity of fruit-derived Lactobacillus to control pathogenic bacteria in fresh cheese and chicken meat.

PubMed

da Costa, Whyara Karoline Almeida; de Souza, Geany Targino; Brandão, Larissa Ramalho; de Lima, Rafael Cardoso; Garcia, Estefânia Fernandes; Dos Santos Lima, Marcos; de Souza, Evandro Leite; Saarela, Maria; Magnani, Marciane

2018-06-01

This study assessed the antagonistic activity of fruit-derived lactic acid bacteria (LAB) strains against food-related bacteria and the effects of the highest organic acids LAB producers on the survival of Listeria monocytogenes and Salmonella Enteritidis PT4 in cheese and chicken meat, respectively. The production of organic acids by the Lactobacillus strains in the tested food matrices was also monitored. All tested LAB strains showed antagonistic activity in vitro on the growth of pathogenic or spoiling food-related bacteria, particularly on L. monocytogenes and/or S. Enteritidis PT4, through the action of non-proteinaceous substances. The highest amounts of acetic and lactic acid were detected in cell free culture supernatants of L. paracasei 108 and L. plantarum 201. In "Minas Frescal" cheese, L. plantarum 49 and L. paracasei 108 decreased the counts of L. monocytogenes, and L. plantarum 201 showed bacteriostatic effects on this pathogen over time. L. paracasei 108 decreased the counts of S. Enteritidis PT4 in ground chicken breast; L. plantarum 49 and L. plantarum 201 failed to decrease the counts of this pathogen. Decreases in counts of L. monocytogenes or S. Enteritidis in "Minas Frescal" cheese and ground chicken breast, respectively, were related with increases in lactic and acetic acid contents and decreases in pH values. L. plantarum 49 and L. paracasei 108 could be used as biopreservation tools in cheese and chicken breast meat, respectively. Copyright © 2018. Published by Elsevier Ltd.

[Effects of nitrogen application rate on faba bean fusarium wilt and rhizospheric microbial metabolic functional diversity].

PubMed

Dong, Yan; Yang, Zhi-xian; Dong, Kun; Tang, Li; Zheng, Yi; Hu, Guo-bin

2013-04-01

A field plot experiment was conducted to study the effects of different nitrogen (N) application rates on the microbial functional diversity in faba bean rhizosphere and the relationships between the microbial functional diversity and the occurrence of faba bean fusarium wilt. Four nitrogen application rates were installed, i. e. , N0(0 kg hm-2 , N1 (56. 25 kg hm-2) , N2(112. 5 kg hm-2), and N3 (168.75 kg hm-2), and Biolog microbial analysis system was applied to study the damage of faba bean fusarium wilt and the rhizospheric microbial metabolic functional diversity. Applying N (N1 N2, and N3) decreased the disease index of faba bean fusarium wilt and the quantity of Fusarium oxysporum significantly, and increased the quantities of bacteria and actinomyces and the ratios of bacteria/fungi and actinomyces/fungi significantly, with the peak values of bacteria and actinomyces, bacteria/fungi, and actinomyces/fungi, and the lowest disease index and F. oxysporum density in N2. As compared with N0, applying N increased the AWCD value significantly, but the effects of different N application rates on the ability of rhizospheric microbes in utilizing six types of carbon sources had definite differences. Under the application of N, the utilization rates of carbohydrates, carboxylic acids, and amino acids by the rhizospheric microbes were higher. Principal component analysis demonstrated that applying N changed the rhizospheric microbial community composition obviously, and the carbohydrates, carboxylic acids, and amino acids were the sensitive carbon sources differentiating the changes of the microbial community induced by N application. Applying N inhibited the utilization of carbohydrates and carboxylic acids but improved the utilization of amino acids and phenolic acids by the rhizospheric microbes, which could be one of the main reasons of applying N being able to reduce the harm of faba bean fusarium wilt. It was suggested that rationally applying N could increase the quantities of rhizospheric bacteria and actinomyces, alter the microbial metabolic function, and decrease F. oxysporum density, being an effective measure to control the occurrence of faba bean fusarium wilt.

SULFUR COMPOUNDS IN MORPHOGENESIS.

DTIC Science & Technology

CHICKENS, GROWTH(PHYSIOLOGY), MITOSIS, BACTERIA, ALGAE, LIPOIC ACID , THIOLS, BELGIUM...ORGANIC SULFUR COMPOUNDS, METABOLISM), (*MORPHOLOGY(BIOLOGY), ORGANIC SULFUR COMPOUNDS), (*NUCLEIC ACIDS , BIOSYNTHESIS), EGGS, EMBRYOS, AMPHIBIANS

21 CFR 133.129 - Dry curd cottage cheese.

Code of Federal Regulations, 2014 CFR

2014-04-01

... of the following methods is employed: (i) Harmless lactic-acid-producing bacteria, with or without... pressed, chilled, worked, seasoned with salt; or (ii) Food grade phosphoric acid, lactic acid, citric acid..., seasoned with salt. (iii) Food grade acids as provided in paragraph (b)(1)(ii) of this section, D-Glucono...

21 CFR 133.129 - Dry curd cottage cheese.

Code of Federal Regulations, 2012 CFR

2012-04-01

... of the following methods is employed: (i) Harmless lactic-acid-producing bacteria, with or without... pressed, chilled, worked, seasoned with salt; or (ii) Food grade phosphoric acid, lactic acid, citric acid..., seasoned with salt. (iii) Food grade acids as provided in paragraph (b)(1)(ii) of this section, D-Glucono...

21 CFR 133.129 - Dry curd cottage cheese.

Code of Federal Regulations, 2013 CFR

2013-04-01

... of the following methods is employed: (i) Harmless lactic-acid-producing bacteria, with or without... pressed, chilled, worked, seasoned with salt; or (ii) Food grade phosphoric acid, lactic acid, citric acid..., seasoned with salt. (iii) Food grade acids as provided in paragraph (b)(1)(ii) of this section, D-Glucono...

Accumulation of Citrulline by Microbial Arginine Metabolism during Alcoholic Fermentation of Soy Sauce.

PubMed

Fang, Fang; Zhang, Jiran; Zhou, Jingwen; Zhou, Zhaohui; Li, Tieqiao; Lu, Liling; Zeng, Weizhu; Du, Guocheng; Chen, Jian

2018-03-07

Citrulline, the major precursor of ethyl carbamate in soy sauce, is an intermediate catabolite of arginine produced by bacteria present in soy sauce moromi mash. Pediococcus acidilactici is responsible for the formation of citrulline during the lactic acid fermentation process of soy sauce. However, citrulline accumulation during the alcoholic fermentation process and the corresponding bacteria involved have not been identified. Salt-tolerant, arginine-utilizing bacteria were isolated from moromi mash during the alcoholic fermentation process. Under normal cultivation conditions, arginine utilization by these strains did not contribute to citrulline accumulation. However, the conversion of arginine to citrulline by these bacteria increased when cultivated during the alcoholic fermentation process. Additionally, the ethanol-enhanced solubility of free fatty acids in moromi mash stimulated the accumulation of citrulline. Staphylococcus exhibited the highest capability in the conversion of arginine to citrulline.

Inactivation of biofilm bacteria.

PubMed Central

LeChevallier, M W; Cawthon, C D; Lee, R G

1988-01-01

The current project was developed to examine inactivation of biofilm bacteria and to characterize the interaction of biocides with pipe surfaces. Unattached bacteria were quite susceptible to the variety of disinfectants tested. Viable bacterial counts were reduced 99% by exposure to 0.08 mg of hypochlorous acid (pH 7.0) per liter (1 to 2 degrees C) for 1 min. For monochloramine, 94 mg/liter was required to kill 99% of the bacteria within 1 min. These results were consistent with those found by other investigators. Biofilm bacteria grown on the surfaces of granular activated carbon particles, metal coupons, or glass microscope slides were 150 to more than 3,000 times more resistant to hypochlorous acid (free chlorine, pH 7.0) than were unattached cells. In contrast, resistance of biofilm bacteria to monochloramine disinfection ranged from 2- to 100-fold more than that of unattached cells. The results suggested that, relative to inactivation of unattached bacteria, monochloramine was better able to penetrate and kill biofilm bacteria than free chlorine. For free chlorine, the data indicated that transport of the disinfectant into the biofilm was a major rate-limiting factor. Because of this phenomenon, increasing the level of free chlorine did not increase disinfection efficiency. Experiments where equal weights of disinfectants were used suggested that the greater penetrating power of monochloramine compensated for its limited disinfection activity. These studies showed that monochloramine was as effective as free chlorine for inactivation of biofilm bacteria. The research provides important insights into strategies for control of biofilm bacteria. Images PMID:2849380

A study on the selection of indigenous leaching-bacteria for effective bioleaching

NASA Astrophysics Data System (ADS)

Oh, S. J.; Cho, K. H.; Kim, B. J.; Choi, N. C.; Park, C. Y.

2012-04-01

Bioleaching technology, which is based on the ability of microorganisms to transform solid compounds into soluble and extractable valuable elements that can be recovered, has been rapidly developed in recent decades for its advantages, which include mild reaction condition, low energy consumption, simple process, low environmental impact and being suitable for low grade mine tailings and residues. The bacteria activities (survival, adaptation of toxically environments etc.) in the bioleaching technology play a key role in the solubilization of metals. The purpose of this study was to selection of optimal leaching-bacteria through changed pH and redox potential on bio-oxidation in batch experiments for successful bioleaching technology. Twenty three indigenous bacteria used throughout this study, leaching-bacteria were obtained from various geochemical conditions; bacteria inhabitation type (acid mine drainage, mine wastes leachate and sulfur hot springs) and base-metal type (sulfur, sulfide, iron and coal). Bio-oxidation experiment result was showed that 9 cycles (1 cycle - 28days) after the leaching-bacteria were inoculated to a leaching medium, pH was observed decreasing and redox potential increased. In the bacteria inhabitation type, bio-oxidation of sulfur hot springs bacteria was greater than other types (acid mine drainage and mine wastes leachate). In addition, bio-oxidation on base-metal type was appeared sulfur was greater than other types (sulfide, iron and coal). This study informs basic knowledge when bacteria apply to eco-/economic resources utilization studies including the biomining and the recycling of mine waste system.

Anaerobic degradation of veratrylglycerol-beta-guaiacyl ether and guaiacoxyacetic acid by mixed rumen bacteria.

PubMed Central

Chen, W; Supanwong, K; Ohmiya, K; Shimizu, S; Kawakami, H

1985-01-01

Veratrylglycerol-beta-guaiacyl ether (0.2 g/liter), a lignin model compound, was found to be degraded by mixed rumen bacteria in a yeast extract medium under strictly anaerobic conditions to the extent of 19% within 24 h. Guaiacoxyacetic acid, 2-(o-methoxyphenoxy)ethanol, vanillic acid, and vanillin were detected as degradation products of veratrylglycerol-beta-guaiacyl ether by thin-layer chromatography, gas chromatography, and gas chromatography-mass spectrometry. Guaiacoxyacetic acid (0.25 g/liter), when added into the medium as a substrate, was entirely degraded within 36 h, resulting in the formation of phenoxyacetic acid, guaiacol, and phenol. These results suggest that the beta-arylether bond, an important intermonomer linkage in lignin, can be cleaved completely by these rumen anaerobes. PMID:3841472

Lactobacillus micheneri sp. nov., Lactobacillus timberlakei sp. nov. and Lactobacillus quenuiae sp. nov., lactic acid bacteria isolated from wild bees and flowers.

PubMed

McFrederick, Quinn S; Vuong, Hoang Q; Rothman, Jason A

2018-06-01

Gram-stain-positive, rod-shaped, non-spore forming bacteria have been isolated from flowers and the guts of adult wild bees in the families Megachilidae and Halictidae. Phylogenetic analysis of the 16S rRNA gene indicated that these bacteria belong to the genus Lactobacillus, and are most closely related to the honey-bee associated bacteria Lactobacillus kunkeei (97.0 % sequence similarity) and Lactobacillus apinorum (97.0 % sequence similarity). Phylogenetic analyses of 16S rRNA genes and six single-copy protein coding genes, in situ and in silico DNA-DNA hybridization, and fatty-acid profiling differentiates the newly isolated bacteria as three novel Lactobacillus species: Lactobacillus micheneri sp. nov. with the type strain Hlig3 T (=DSM 104126 T ,=NRRL B-65473 T ), Lactobacillus timberlakei with the type strain HV_12 T (=DSM 104128 T ,=NRRL B-65472 T ), and Lactobacillus quenuiae sp. nov. with the type strain HV_6 T (=DSM 104127 T ,=NRRL B-65474 T ).

Microbiological Quality of Panicum maximum Grass Silage with Addition of Lactobacillus sp. as Starter

NASA Astrophysics Data System (ADS)

Sumarsih, S.; Sulistiyanto, B.; Utama, C. S.

2018-02-01

The aim of the research was to evaluate microbiological quality of Panicum maximum grass silage with addition Lactobacillus sp as starter. The completely randomized design was been used on this research with 4 treaments and 3 replications. The treatments were P0 ( Panicum maximum grass silage without addition Lactobacillus sp ), P1 ( Panicum maximum grass silage with 2% addition Lactobacillus sp), P2 (Panicum maximum grass silage with 4% addition Lactobacillus sp) and P3 (Panicum maximum grass silage with 6% addition Lactobacillus sp).The parameters were microbial populations of Panicum maximum grass silage (total lactic acid bacteria, total bacteria, total fungi, and Coliform bacteria. The data obtained were analyzed variance (ANOVA) and further tests performed Duncan’s Multiple Areas. The population of lactic acid bacteria was higher (P<0.05) and the total bacteria, fungi and Coliform were lower (P<0.05) with addition Lactobacillus sp. Microbiological quality of Panicum maximum grass silage with addition Lactobacillus sp was better than no addition Lactobacillus sp.

Dynamic metabolic exchange governs a marine algal-bacterial interaction.

PubMed

Segev, Einat; Wyche, Thomas P; Kim, Ki Hyun; Petersen, Jörn; Ellebrandt, Claire; Vlamakis, Hera; Barteneva, Natasha; Paulson, Joseph N; Chai, Liraz; Clardy, Jon; Kolter, Roberto

2016-11-18

Emiliania huxleyi is a model coccolithophore micro-alga that generates vast blooms in the ocean. Bacteria are not considered among the major factors influencing coccolithophore physiology. Here we show through a laboratory model system that the bacterium Phaeobacter inhibens , a well-studied member of the Roseobacter group, intimately interacts with E. huxleyi. While attached to the algal cell, bacteria initially promote algal growth but ultimately kill their algal host. Both algal growth enhancement and algal death are driven by the bacterially-produced phytohormone indole-3-acetic acid. Bacterial production of indole-3-acetic acid and attachment to algae are significantly increased by tryptophan, which is exuded from the algal cell. Algal death triggered by bacteria involves activation of pathways unique to oxidative stress response and programmed cell death. Our observations suggest that bacteria greatly influence the physiology and metabolism of E. huxleyi. Coccolithophore-bacteria interactions should be further studied in the environment to determine whether they impact micro-algal population dynamics on a global scale.

Characterization of cucumber fermentation spoilage bacteria by enrichment culture and 16S rDNA cloning.

PubMed

Breidt, Fred; Medina, Eduardo; Wafa, Doria; Pérez-Díaz, Ilenys; Franco, Wendy; Huang, Hsin-Yu; Johanningsmeier, Suzanne D; Kim, Jae Ho

2013-03-01

Commercial cucumber fermentations are typically carried out in 40000 L fermentation tanks. A secondary fermentation can occur after sugars are consumed that results in the formation of acetic, propionic, and butyric acids, concomitantly with the loss of lactic acid and an increase in pH. Spoilage fermentations can result in significant economic loss for industrial producers. The microbiota that result in spoilage remain incompletely defined. Previous studies have implicated yeasts, lactic acid bacteria, enterobacteriaceae, and Clostridia as having a role in spoilage fermentations. We report that Propionibacterium and Pectinatus isolates from cucumber fermentation spoilage converted lactic acid to propionic acid, increasing pH. The analysis of 16S rDNA cloning libraries confirmed and expanded the knowledge gained from previous studies using classical microbiological methods. Our data show that Gram-negative anaerobic bacteria supersede Gram-positive Fermincutes species after the pH rises from around 3.2 to pH 5, and propionic and butyric acids are produced. Characterization of the spoilage microbiota is an important first step in efforts to prevent cucumber fermentation spoilage. An understanding of the microorganisms that cause commercial cucumber fermentation spoilage may aid in developing methods to prevent the spoilage from occurring. © 2013 Institute of Food Technologists®

[Anaerobic biodegradation of phthalic acid esters (Paes) in municipal sludge].

PubMed

Liang, Zhi-Feng; Zhou, Wen; Lin, Qing-Qi; Yang, Xiu-Hong; Wang, Shi-Zhong; Cai, Xin-De; Qiu, Rong-Liang

2014-04-01

Phthalic acid esters (PAEs), a class of organic pollutants with potent endocrine-disrupting properties, are widely present in municipal sludge. Study of PAEs biodegradation under different anaerobic biological treatment processes of sludge is, therefore, essential for a safe use of sludge in agricultural practice. In this study, we selected two major sludge PAEs, i.e. di-n-butyl phthalate (DBP) and di-(2-enthylhexyl) phthalate (DEHP), to investigate their biodegradation behaviors in an anaerobic sludge digestion system and a fermentative hydrogen production system. The possible factors influencing PAEs biodegradation in relation to changes of sludge properties were also discussed. The results showed that the biodegradation of DBP reached 99.6% within 6 days, while that of DEHP was 46.1% during a 14-day incubation period in the anaerobic digestion system. By comparison, only 19.5% of DBP was degraded within 14 days in the fermentative hydrogen production system, while no degradation was detected for DEHP. The strong inhibition of the degradation of both PAEs in the fermentative hydrogen production system was ascribed to the decreases in microbial biomass and ratios of gram-positive bacteria/gram-negative bacteria and fungi/ bacteria, and the increase of concentrations of volatile fatty acids (e. g. acetic acid, propionic acid and butyric acid) during the fermentative hydrogen-producing process.

Does the high nucleic acid content of individual bacterial cells allow us to discriminate between active cells and inactive cells in aquatic systems?

PubMed

Lebaron, P; Servais, P; Agogué, H; Courties, C; Joux, F

2001-04-01

The nucleic acid contents of individual bacterial cells as determined with three different nucleic acid-specific fluorescent dyes (SYBR I, SYBR II, and SYTO 13) and flow cytometry were compared for different seawater samples. Similar fluorescence patterns were observed, and bacteria with high apparent nucleic acid contents (HNA) could be discriminated from bacteria with low nucleic acid contents (LNA). The best discrimination between HNA and LNA cells was found when cells were stained with SYBR II. Bacteria in different water samples collected from seven freshwater, brackish water, and seawater ecosystems were prelabeled with tritiated leucine and then stained with SYBR II. After labeling and staining, HNA, LNA, and total cells were sorted by flow cytometry, and the specific activity of each cellular category was determined from leucine incorporation rates. The HNA cells were responsible for most of the total bacterial production, and the specific activities of cells in the HNA population varied between samples by a factor of seven. We suggest that nucleic acid content alone can be a better indicator of the fraction of growing cells than total counts and that this approach should be combined with other fluorescent physiological probes to improve detection of the most active cells in aquatic systems.

Does the High Nucleic Acid Content of Individual Bacterial Cells Allow Us To Discriminate between Active Cells and Inactive Cells in Aquatic Systems?

PubMed Central

Lebaron, Philippe; Servais, Pierre; Agogué, Helene; Courties, Claude; Joux, Fabien

2001-01-01

The nucleic acid contents of individual bacterial cells as determined with three different nucleic acid-specific fluorescent dyes (SYBR I, SYBR II, and SYTO 13) and flow cytometry were compared for different seawater samples. Similar fluorescence patterns were observed, and bacteria with high apparent nucleic acid contents (HNA) could be discriminated from bacteria with low nucleic acid contents (LNA). The best discrimination between HNA and LNA cells was found when cells were stained with SYBR II. Bacteria in different water samples collected from seven freshwater, brackish water, and seawater ecosystems were prelabeled with tritiated leucine and then stained with SYBR II. After labeling and staining, HNA, LNA, and total cells were sorted by flow cytometry, and the specific activity of each cellular category was determined from leucine incorporation rates. The HNA cells were responsible for most of the total bacterial production, and the specific activities of cells in the HNA population varied between samples by a factor of seven. We suggest that nucleic acid content alone can be a better indicator of the fraction of growing cells than total counts and that this approach should be combined with other fluorescent physiological probes to improve detection of the most active cells in aquatic systems. PMID:11282632

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

Coleman, R.

Plastics can be made from starchy food waste. This article describes a method by which these plastics break down into harmless chemicals when exposed to sunlight, water or bacteria. Degradable trash bags and agricultural mulch films can replace some of the millions of pounds of nondegradable plastics used each year. Researchers at Argonne National Laboratory developed that involves enzymatically converting potato waste into glucose, fermenting the glucose to lactic acid using bacteria, and then using the lactic acid to construct fully degradable plastics.

[Bio-ecological control of chronic liver disease and encephalopathy].

PubMed

Bengmark, S; Di Cocco, P; Clemente, K; Corona, L; Angelico, R; Manzia, T; Famulari, A; Pisani, F; Orlando, G

2011-08-01

Minimal encephalopathy was originally associated with chronic liver disease but is increasingly associated with most other chronic diseases and particularly with diabetes and also chronic disorders in other organs: kidneys, lungs, thyroid and with obesity. It is increasingly with dramatically increased and more or less permanent increase in systemic inflammation, most likely a result of Western lifestyle. Frequent physical exercise and intake of foods rich in vitamins, antioxidants, fibres, lactic acid bacteria etc in combination with reduction in intake of refined and processed foods is known to reduce systemic inflammation and prevent chronic diseases. Some lactic acid bacteria, especially Lb paracasei, lb plantarum and pediococcus pentosaceus have proven effective to reduce inflammation and eliminate encephalopathy. Significant reduction in blood ammonia levels and endotoxin levels were reported in parallel to improvement of liver disease. Subsequent studies with other lactic acid bacteria seem to demonstrate suppression of inflammation and one study also provides evidence of clinical improvement.

Antimycobacterial, antimicrobial, and biocompatibility properties of para-aminosalicylic acid with zinc layered hydroxide and Zn/Al layered double hydroxide nanocomposites

PubMed Central

Saifullah, Bullo; El Zowalaty, Mohamed E; Arulselvan, Palanisamy; Fakurazi, Sharida; Webster, Thomas J; Geilich, Benjamin M; Hussein, Mohd Zobir

2014-01-01

The treatment of tuberculosis by chemotherapy is complicated due to multiple drug prescriptions, long treatment duration, and adverse side effects. We report here for the first time an in vitro therapeutic effect of nanocomposites based on para-aminosalicylic acid with zinc layered hydroxide (PAS-ZLH) and zinc-aluminum layered double hydroxides (PAS-Zn/Al LDH), against mycobacteria, Gram-positive bacteria, and Gram-negative bacteria. The nanocomposites demonstrated good antimycobacterial activity and were found to be effective in killing Gram-positive and Gram-negative bacteria. A biocompatibility study revealed good biocompatibility of the PAS-ZLH nanocomposites against normal human MRC-5 lung cells. The para-aminosalicylic acid loading was quantified with high-performance liquid chromatography analysis. In summary, the present preliminary in vitro studies are highly encouraging for further in vivo studies of PAS-ZLH and PAS-Zn/Al LDH nanocomposites to treat tuberculosis. PMID:25114509

Determination of antibiotic resistance of lactic acid bacteria isolated from traditional Turkish fermented dairy products.

PubMed

Erginkaya, Z; Turhan, E U; Tatlı, D

2018-01-01

In this study, the antibiotic resistance (AR) of lactic acid bacteria (LAB) isolated from traditional Turkish fermented dairy products was investigated. Yogurt, white cheese, tulum cheese, cokelek, camız cream and kefir as dairy products were collected from various supermarkets. Lactic acid bacteria such as Lactobacillus spp., Streptococcus spp., Bifidobacterium spp., and Enterecoccus spp. were isolated from these dairy products. Lactobacillus spp. were resistant to vancomycin (58%), erythromycin (10.8%), tetracycline (4.3%), gentamicin (28%), and ciprofloxacin (26%). Streptococcus spp. were resistant to vancomycin (40%), erythromycin (10%), chloramphenicol (10%), gentamicin (20%), and ciprofloxacin (30%). Bifidobacterium spp. were resistant to vancomycin (60%), E 15 (6.6%), gentamicin (20%), and ciprofloxacin (33%). Enterococcus spp. were resistant to vancomycin (100%), erythromycin (100%), rifampin (100%), and ciprofloxacin (100%). As a result, LAB islated from dairy products in this study showed mostly resistance to vancomycin.

Characterization of Lactic Acid Bacteria Isolated from Sauce-type Kimchi

PubMed Central

Jung, Suk Hee; Park, Joung Whan; Cho, Il Jae; Lee, Nam Keun; Yeo, In-Cheol; Kim, Byung Yong; Kim, Hye Kyung; Hahm, Young Tae

2012-01-01

This study was carried out to investigate the isolation and characterization of lactic acid bacteria (LAB) from naturally fermented sauce-type kimchi. Sauce-type kimchi was prepared with fresh, chopped ingredients (Korean cabbage, radish, garlic, ginger, green onion, and red pepper). The two isolated bacteria from sauce-type kimchi were identified as Pediococcus pentosaceus and Lactobacillus brevis by 16S rDNA sequencing and tentatively named Pediococcus sp. IJ-K1 and Lactobacillus sp. IJ-K2, respectively. Pediococcus sp. IJ-K1 was isolated from the early and middle fermentation stages of sauce-type kimchi whereas Lactobacillus sp. IJ-K2 was isolated from the late fermentation stage. The resistance of Pediococcus sp. IJ-K1 and Lactobacillus sp. IJ-K2 to artificial gastric and bile acids led to bacterial survival rates that were 100% and 84.21%, respectively. PMID:24471087

DNA Fingerprinting of Lactic Acid Bacteria in Sauerkraut Fermentations▿ † ‡

PubMed Central

Plengvidhya, Vethachai; Breidt, Fredrick; Lu, Zhongjing; Fleming, Henry P.

2007-01-01

Previous studies using traditional biochemical identification methods to study the ecology of commercial sauerkraut fermentations revealed that four species of lactic acid bacteria, Leuconostoc mesenteroides, Lactobacillus plantarum, Pediococcus pentosaceus, and Lactobacillus brevis, were the primary microorganisms in these fermentations. In this study, 686 isolates were collected from four commercial fermentations and analyzed by DNA fingerprinting. The results indicate that the species of lactic acid bacteria present in sauerkraut fermentations are more diverse than previously reported and include Leuconostoc citreum, Leuconostoc argentinum, Lactobacillus paraplantarum, Lactobacillus coryniformis, and Weissella sp. The newly identified species Leuconostoc fallax was also found. Unexpectedly, only two isolates of P. pentosaceus and 15 isolates of L. brevis were recovered during this study. A better understanding of the microbiota may aid in the development of low-salt fermentations, which may have altered microflora and altered sensory characteristics. PMID:17921264

Sourdough-Based Biotechnologies for the Production of Gluten-Free Foods

PubMed Central

Nionelli, Luana; Rizzello, Carlo Giuseppe

2016-01-01

Sourdough fermentation, a traditional biotechnology for making leavened baked goods, was almost completely replaced by the use of baker’s yeast and chemical leavening agents in the last century. Recently, it has been rediscovered by the scientific community, consumers, and producers, thanks to several effects on organoleptic, technological, nutritional, and functional features of cereal-based products. Acidification, proteolysis, and activation of endogenous enzymes cause several changes during sourdough fermentation, carried out by lactic acid bacteria and yeasts, which positively affect the overall quality of the baked goods. In particular, the hydrolysis of native proteins of the cereal flours may improve the functional features of baked goods. The wheat flour processed with fungal proteases and selected lactic acid bacteria was demonstrated to be safe for coeliac patients. This review article focuses on the biotechnologies that use selected sourdough lactic acid bacteria to potentially counteract the adverse reactions to gluten, and the risk of gluten contamination. PMID:28231160

[Content of salicylic and jasmonic acids in pea roots (Pisum sativum L.) at the initial stage of symbiotic or pathogenic interaction with bacteria of the family Rhizobiaceae].

PubMed

Rudikovskaya, E G; Akimova, G P; Rudikovskii, A V; Katysheva, N B; Dudareva, L V

2017-01-01

A change in the contents of endogenous salicylic and jasmonic acids in the roots of the host plant at the preinfectious stage of interaction with symbiotic (Rhizobium leguminosarum) and pathogenic (Agrobacterium rizogenes) bacteria belonging for to the family Rhizobiaceae was studied. It was found that the jasmonic acid content increased 1.5–2 times 5 min after inoculation with these bacterial species. It was shown that dynamics of the change in the JA and SA contents depends on the type of infection. Thus, the JA content decreased in the case of pathogenesis, while the SA content increased. At the same time, an increased JA content was observed during symbiosis. The observed regularities could indicate the presence of different strategies of hormonal regulation for interaction with symbiotic and pathogenic bacteria belonging to the family Rhizobiaceae in peas plants.

Nucleic Acid Immunity.

PubMed

Hartmann, G

2017-01-01

Organisms throughout biology need to maintain the integrity of their genome. From bacteria to vertebrates, life has established sophisticated mechanisms to detect and eliminate foreign genetic material or to restrict its function and replication. Tremendous progress has been made in the understanding of these mechanisms which keep foreign or unwanted nucleic acids from viruses or phages in check. Mechanisms reach from restriction-modification systems and CRISPR/Cas in bacteria and archaea to RNA interference and immune sensing of nucleic acids, altogether integral parts of a system which is now appreciated as nucleic acid immunity. With inherited receptors and acquired sequence information, nucleic acid immunity comprises innate and adaptive components. Effector functions include diverse nuclease systems, intrinsic activities to directly restrict the function of foreign nucleic acids (e.g., PKR, ADAR1, IFIT1), and extrinsic pathways to alert the immune system and to elicit cytotoxic immune responses. These effects act in concert to restrict viral replication and to eliminate virus-infected cells. The principles of nucleic acid immunity are highly relevant for human disease. Besides its essential contribution to antiviral defense and restriction of endogenous retroelements, dysregulation of nucleic acid immunity can also lead to erroneous detection and response to self nucleic acids then causing sterile inflammation and autoimmunity. Even mechanisms of nucleic acid immunity which are not established in vertebrates are relevant for human disease when they are present in pathogens such as bacteria, parasites, or helminths or in pathogen-transmitting organisms such as insects. This review aims to provide an overview of the diverse mechanisms of nucleic acid immunity which mostly have been looked at separately in the past and to integrate them under the framework nucleic acid immunity as a basic principle of life, the understanding of which has great potential to advance medicine. © 2017 Elsevier Inc. All rights reserved.

Effects of applying molasses, lactic acid bacteria and propionic acid on fermentation quality, aerobic stability and in vitro gas production of total mixed ration silage prepared with oat-common vetch intercrop on the Tibetan Plateau.

PubMed

Chen, Lei; Guo, Gang; Yuan, Xianjun; Zhang, Jie; Li, Junfeng; Shao, Tao

2016-03-30

The objective of this study was to investigate the effect of molasses, lactic acid bacteria and propionic acid on the fermentation quality, aerobic stability and in vitro gas production of total mixed ration (TMR) silage prepared with oat-common vetch intercrop on the Tibetan plateau. TMR (436 g kg(-1) dry matter (DM)) was ensiled with six experimental treatments: (1) no additives (control); (2) molasses (M); (3) an inoculant (Lactobacillus plantarum) (L); (4) propionic acid (P); (5) molasses + propionic acid (MP); (6) inoculant + propionic acid (LP). All silages were well preserved with low pH (< 4.19) and NH3-N contents, and high lactic acid contents after ensiling for 45 days. L and PL silages underwent a more efficient fermentation than silages without L. P and MP silages inhibited lactic acid production. Under aerobic conditions, M and L silage reduced aerobic stability for 15 and 74 h, respectively. All silages that had propionic acid in their treatments markedly (P < 0.05) improved the aerobic stability. After 72 h incubation, all additives treatments increased (P < 0.05) the 72 h cumulative gas production and in vitro DM digestibility (IVDMD) as compared with the control. L treatment decreased (P < 0.05) in vitro neutral detergent fibre degradability. Our findings show that TMR prepared with oat-common vetch intercrop can be well preserved. Although propionic acid is compatible with lactic acid bacteria, and when used together, they had minor effects on fermentation, aerobic stability and in vitro digestibility of TMR silage prepared with oat-common vetch intercrop. © 2015 Society of Chemical Industry.

Recent Developments for Remediating Acidic Mine Waters Using Sulfidogenic Bacteria

PubMed Central

Bitencourt, José A. P.; Sahoo, Prafulla K.; Alves, Joner Oliveira; Siqueira, José O.

2017-01-01

Acidic mine drainage (AMD) is regarded as a pollutant and considered as potential source of valuable metals. With diminishing metal resources and ever-increasing demand on industry, recovering AMD metals is a sustainable initiative, despite facing major challenges. AMD refers to effluents draining from abandoned mines and mine wastes usually highly acidic that contain a variety of dissolved metals (Fe, Mn, Cu, Ni, and Zn) in much greater concentration than what is found in natural water bodies. There are numerous remediation treatments including chemical (lime treatment) or biological methods (aerobic wetlands and compost bioreactors) used for metal precipitation and removal from AMD. However, controlled biomineralization and selective recovering of metals using sulfidogenic bacteria are advantageous, reducing costs and environmental risks of sludge disposal. The increased understanding of the microbiology of acid-tolerant sulfidogenic bacteria will lead to the development of novel approaches to AMD treatment. We present and discuss several important recent approaches using low sulfidogenic bioreactors to both remediate and selectively recover metal sulfides from AMD. This work also highlights the efficiency and drawbacks of these types of treatments for metal recovery and points to future research for enhancing the use of novel acidophilic and acid-tolerant sulfidogenic microorganisms in AMD treatment. PMID:29119111

Exploitation of Albanian wheat cultivars: characterization of the flours and lactic acid bacteria microbiota, and selection of starters for sourdough fermentation.

PubMed

Nionelli, Luana; Curri, Nertila; Curiel, José Antonio; Di Cagno, Raffaella; Pontonio, Erica; Cavoski, Ivana; Gobbetti, Marco; Rizzello, Carlo Giuseppe

2014-12-01

Six Albanian soft and durum wheat cultivars were characterized based on chemical and technological features, showing different attitudes for bread making. Gliadin and glutenin fractions were selectively extracted from flours, and subjected to two-dimensional electrophoresis. Linja 7 and LVS flours showed the best characteristics, and abundance of high molecular weight (HMW)-glutenins. Type I sourdoughs were prepared through back slopping procedure, and the lactic acid bacteria were typed and identified. Lactobacillus plantarum and Leuconostoc mesenteroides were the predominant species. Thirty-eight representative isolates were singly used for sourdough fermentation of soft and durum wheat Albanian flours and their selection was carried out based on growth and acidification, quotient of fermentation, and proteolytic activity. Two different pools of lactic acid bacteria were designed to ferment soft or durum wheat flours. Sourdough fermentation with mixed and selected starters positively affected the quotient of fermentation, concentration of free amino acids, profile of phenolic acids, and antioxidant and phytase activities. This study provided the basis to exploit the potential of wheat Albanian flours based on an integrated approach, which considered the characterization of the flours and the processing conditions. Copyright © 2014 Elsevier Ltd. All rights reserved.

Modulation of the Lactobacillus acidophilus La-5 lipidome by different growth conditions.

PubMed

Hansen, Marie-Louise R W; Clausen, Anders; Ejsing, Christer S; Risbo, Jens

2015-10-01

Probiotics are bacteria used in the food industry due to their potential health benefits. In this study, the plasma membrane of the probiotic Lactobacillus acidophilus La-5 was investigated using state-of-the-art high-resolution shotgun lipidomics. Comparisons of the lipidome of the plasma membrane were done after altering the fatty acid composition by supplementing L. acidophilus La-5 with saturated, mono-, di- and tri-unsaturated fatty acids during fermentation. The plasma membrane with the highest degree of saturation resulted in a lipid composition with the highest proportion of cardiolipin (CL) and lowest proportion of monolysocardiolipin (MLCL). No significant changes were found for other lipid classes. The bacteria grown with di- and tri-unsaturated fatty acids were expected to have more unsaturated plasma membranes than bacteria grown with mono-unsaturated fatty acids. This was also the case for MLCL, but the numbers of double bonds for CL were quite similar for these three samples. The results indicate that L. acidophilus La-5 possesses a molecular mechanism for remodelling and optimizing the fatty acid composition of CL and MLCL species and the molar ratio of CL and MLCL. This study contributes new knowledge on the previously uninvestigated lipidome of L. acidophilus La-5.