Fritz, T M; Burg, G; Krasovec, M
Melaleuca alternifolia is a coniferous tree found in tropical regions, the needles contain an essential oil that is used in medical and cosmetic products. The essential oil contains turpentines (limonene, alpha-pinene, phellandrene) that are potentially allergenic. In 1997, 1216 patients were patch tested in our dermatoligic unit. Fourteen of them tested because of eczema used products containing tea tree oil. The patients used creams, hair products and essential oils containing Melaleuca alternifolia for cosmetic reasons and to treat skin affections. They were patch tested for a standard panel of allergens, topical emulgators, perfumes, plants, topical medications, metal, gloves, topical disinfectants and preservatives, dental products and rubber derivatives. Products containing Melaleuca alternifolia were tested concentrated or diluted. We report on 7 cases of patients with an allergic contact dermatitis due to tea tree oil. Two of them also exhibited from a delayed type IV hypersensitivity towards fragrance-mix or colophony suggesting the possibility of cross reaction or an allergic group reaction caused by contamination of the colophony with the volatile fraction of turpentines. The allergic potential of low concentrations of Melaleuca alternifolia is presumed to be low on healthy skin. Photoaged Melaleuca alternifolia must be considered to be a stronger sensitizer.
Gómez-Rincón, Carlota; Langa, Elisa; Murillo, Paula; Valero, Marta Sofía; Berzosa, César; López, Víctor
Nematicidal activity of Melaleuca alternifolia essential oil, commonly known as tea tree oil (TTO), was assayed in vitro against L3 larvae of Anisakis simplex. The results showed a mortality of 100% for concentrations between 7 and 10 μL/mL after 48 h of incubation, obtaining an LD50 value of 4.53 μL/mL after 24 hours and 4.27 μL/mL after 48 hours. Concentration-dependent inhibition of acetylcholinesterase was observed for tea tree essential oil showing inhibition values of 100% at 100 μL/mL. This fact suggests that TTO may act as an AChE inhibitor. Terpinen-4-ol was discarded as main larvicide compound as it did not show larvicidal or anticholinesterase activity. The data obtained suggest that the essential oil of Melaleuca alternifolia may have a great therapeutic potential for the treatment of human anisakiasis.
Chin, Karen B; Cordell, Barbara
Numerous studies have shown the promising antibacterial effects of Melaleuca alternifolia, or tea tree essential oil. The study detailed here replicates in humans a 2004 in vitro study that used a dressing model over Petri dishes to determine the antimicrobial effects of the fumes of tea tree essential oil. The current study used the same dressing model with patients who had wounds infected with Staphylococcus aureus. Ten participants volunteered for the quasi-experimental study, and four of the 10 were used as matched participants to compare wound healing times between conventional treatment alone and conventional treatment plus fumes of tea tree essential oil. The results demonstrated decreased healing time in all but one of the participants treated with tea tree oil. The differences between the matched participants were striking. The results of this small investigational study indicate that additional study is warranted.
Hammer, K A; Carson, C F; Riley, T V
The in vitro activity of Melaleuca alternifolia (tea tree) oil against dermatophytes (n = 106) and filamentous fungi (n = 78) was determined. Tea tree oil MICs for all fungi ranged from 0.004% to 0.25% and minimum fungicidal concentrations (MFCs) ranged from <0.03% to 8.0%. Time-kill experiments with 1-4 x MFC demonstrated that three of the four test organisms were still detected after 8 h of treatment, but not after 24 h. Comparison of the susceptibility to tea tree oil of germinated and non-germinated Aspergillus niger conidia showed germinated conidia to be more susceptible than non-germinated conidia. These data demonstrate that tea tree oil has both inhibitory and fungicidal activity.
Kulik, E; Lenkeit, K; Meyer, J
The essential oil of Melaleuca alternifolia (tea tree oil) exhibits antimicrobial activity against a wide range of Gram-positive and Gram-negative bacteria, yeasts and fungi. In this study the bacteriostatic and bacteriocidal/fungicidal activity of a tea tree oil solution, of a new tea tree oil (Tebodont) and the respective placebo-gel, of a chlorhexidindigluconate-solution and of PlakOut was tested in vitro against ten different oral microorganisms. Minimum inhibitory concentrations were in the range from 0.0293% to 1.25% for the tea tree oil solution and from 0.0082% to 1.25% for the tea tree oil gel. The values for minimum bacteriocidal/fungicidal concentrations were in the range from 0.0521% to 2.5% for the tea tree oil solution and from <0.0098% to 3.33% for the tea tree oil gel. The most susceptible microorganisms were Actinobacillus actinomycetemcomitans, Fusobacterium nucleatum, and Porphyromonas gingivalis, whereas Streptococcus mutans and Prevotella intermedia were the least susceptible ones. Both for the chlorhexidindigluconate solution and for PlakOut the values for the minimal inhibitory concentration and for the minimal cidal concentration were between <0.0002% and 0.0125%.
Millar, B Cherie; Moore, John E
Tea tree oil (TTO) (Melaleuca alternifolia) has been used recently as an effective topical application for the treatment of skin infections due to a variety of aetiological microbial agents, including mainly bacterial infections. We detail the first report in the peer-reviewed literature of the successful treatment with TTO of a paediatric patient with warts on her right middle finger. TTO was applied topically once daily to the lesions for 12 days, with a successful outcome, including complete re-epithelization of the infected areas. The case highlights the potential use of TTO in the treatment of common warts due to human papilloma virus.
Cox, S D; Mann, C M; Markham, J L; Bell, H C; Gustafson, J E; Warmington, J R; Wyllie, S G
The essential oil of Melaleuca alternifolia (tea tree) exhibits broad-spectrum antimicrobial activity. Its mode of action against the Gram-negative bacterium Escherichia coli AG100, the Gram-positive bacterium Staphylococcus aureus NCTC 8325, and the yeast Candida albicans has been investigated using a range of methods. We report that exposing these organisms to minimum inhibitory and minimum bactericidal/fungicidal concentrations of tea tree oil inhibited respiration and increased the permeability of bacterial cytoplasmic and yeast plasma membranes as indicated by uptake of propidium iodide. In the case of E. coli and Staph. aureus, tea tree oil also caused potassium ion leakage. Differences in the susceptibility of the test organisms to tea tree oil were also observed and these are interpreted in terms of variations in the rate of monoterpene penetration through cell wall and cell membrane structures. The ability of tea tree oil to disrupt the permeability barrier of cell membrane structures and the accompanying loss of chemiosmotic control is the most likely source of its lethal action at minimum inhibitory levels.
Langa, Elisa; Murillo, Paula
Nematicidal activity of Melaleuca alternifolia essential oil, commonly known as tea tree oil (TTO), was assayed in vitro against L3 larvae of Anisakis simplex. The results showed a mortality of 100% for concentrations between 7 and 10 μL/mL after 48 h of incubation, obtaining an LD50 value of 4.53 μL/mL after 24 hours and 4.27 μL/mL after 48 hours. Concentration-dependent inhibition of acetylcholinesterase was observed for tea tree essential oil showing inhibition values of 100% at 100 μL/mL. This fact suggests that TTO may act as an AChE inhibitor. Terpinen-4-ol was discarded as main larvicide compound as it did not show larvicidal or anticholinesterase activity. The data obtained suggest that the essential oil of Melaleuca alternifolia may have a great therapeutic potential for the treatment of human anisakiasis. PMID:24967378
Hammer, K A; Dry, L; Johnson, M; Michalak, E M; Carson, C F; Riley, T V
The in vitro activity of Melaleuca alternifolia (tea tree) oil against 161 isolates of oral bacteria from 15 genera was determined. Minimum inhibitory concentrations (MIC) and minimum bactericidal concentrations (MBC) ranged from 0.003 to 2.0% (v/v). MIC90 values were 1.0% (v/v) for Actinomyces spp., Lactobacillus spp., Streptococcus mitis and Streptococcus sanguis, and 0.1% (v/v) for Prevotella spp. Isolates of Porphyromonas, Prevotella and Veillonella had the lowest MICs and MBCs, and isolates of Streptococcus, Fusobacterium and Lactobacillus had the highest. Time kill studies with Streptococcus mutans and Lactobacillus rhamnosus showed that treatment with > or = 0.5% tea tree oil caused decreases in viability of >3 log colony forming units/ml after only 30 s, and viable organisms were not detected after 5 min. These studies indicate that a range of oral bacteria are susceptible to tea tree oil, suggesting that tea tree oil may be of use in oral healthcare products and in the maintenance of oral hygiene.
Concha, J M; Moore, L S; Holloway, W J
Tea-tree oil (oil of Melaleuca alternifolia) has recently received much attention as a natural remedy for bacterial and fungal infections of the skin and mucosa. As with most naturally occurring agents, claims of effectiveness have been only anecdotal; however, several published studies have recently demonstrated tea-tree oil's antibacterial activity. This study was conducted to determine the activity of tea-tree oil against 58 clinical isolates: Candida albicans (n = 10), Trichophyton rubrum (n = 8), Trichophyton mentagrophytes (n = 9), Trichophyton tonsurans (n = 10), Aspergillus niger (n = 9), Penicillium species (n = 9), Epidermophyton floccosum (n = 2), and Microsporum gypsum (n = 1). Tea-tree oil showed inhibitory activity against all isolates tested except one strain of E floccosum. These in vitro results suggest that tea-tree oil may be useful in the treatment of yeast and fungal mucosal and skin infections.
Pazinato, Rafael; Klauck, Vanderlei; Volpato, Andreia; Tonin, Alexandre A; Santos, Roberto C; de Souza, Márcia E; Vaucher, Rodrigo A; Raffin, Renata; Gomes, Patrícia; Felippi, Candice C; Stefani, Lenita M; Da Silva, Aleksandro S
The aim of this study was to verify the influence of tea tree oil (TTO) (Melaleuca alternifolia) tested in its pure and nanostructured (TTO nanoparticles) forms on the reproduction of female Rhipicephalus microplus. For our purpose, female ticks were collected from naturally infected animals and treated in vitro with TTO (1, 5, and 10 %) and TTO nanoparticles (0.075, 0.375, and 0.75 %). In order to validate the tests, they were performed in triplicate using positive (amitraz) and negative (untreated) controls. It was possible to observe that pure TTO (5 and 10 %) and TTO nanoparticles (0.375 and 0.75 %) showed 100 % reproductive inhibition on female ticks. Additionally, pure TTO (1 %) also showed an acaricide effect (70 %), similarly to the positive control (78.3 %). This is the first study demonstrating the activity of pure TTO and TTO nanoparticles on female ticks. Therefore, based on these results, we were able to show that both forms and all concentrations of M. alternifolia affected tick reproduction by inhibiting egg laying and hatching. We were also able to show that TTO nanoparticles potentiated the inhibitor effect of pure TTO on the reproduction of R. microplus.
James, P J; Callander, J T
The in vivo pediculicidal effectiveness of 1% and 2% formulations of tea tree (Melaleuca alternifolia) oil (TTO) against sheep chewing lice (Bovicola ovis) was tested in two pen studies. Immersion dipping of sheep shorn two weeks before treatment in both 1% and 2% formulations reduced lice to non detectable levels. No lice were found on any of the treated sheep despite careful inspection of at least 40 fleece partings per animal at 2, 6, 12 and 20 weeks after treatment. In the untreated sheep louse numbers increased from a mean (± SE) of 2.4 (± 0.7) per 10 cm fleece part at 2 weeks to 12.3 (± 4.2) per part at 20 weeks. Treatment of sheep with 6 months wool by jetting (high pressure spraying into the fleece) reduced louse numbers by 94% in comparison to controls at two weeks after treatment with both 1% and 2% TTO formulations. At 6 and 12 weeks after treatment reductions were 94% and 91% respectively with the 1% formulation and 78% and 84% respectively with the 2% formulation. TTO treatment also appeared to reduce wool damage in infested sheep. Laboratory studies indicated that tea tree oil 'stripped' from solution with a progressive reduction in concentration as well as volume as more wool was dipped, indicating that reinforcement of active ingredient would be required to maintain effectiveness when large numbers of sheep are treated. The results of these studies suggest significant potential for the development of ovine lousicides incorporating TTO.
Hammer, K A; Carson, C F; Riley, T V
The effect of some potentially interfering substances and conditions on the antimicrobial activity of Melaleuca alternifolia (tea tree) oil was investigated. Agar and broth dilution methods were used to determine minimum inhibitory and cidal concentrations of tea tree oil in the presence and absence of each potentially interfering substance. Activity was determined against Gram-positive and -negative bacteria, and Candida albicans. Minimum inhibitory or cidal concentrations differed from controls by two or more dilutions, for one or more organisms, where Tween-20, Tween-80, skim-milk powder and bovine serum albumin were assessed. These differences were not seen when assays were performed in anaerobic conditions, or in the presence of calcium and magnesium ions. The effect of organic matter on the antimicrobial activity of tea tree oil was also investigated by an organic soil neutralization test. Organisms were exposed to lethal concentrations of tea tree oil ranging from 1-10% (v/v), in the presence of 1-30% (w/v) dry bakers' yeast. After 10 min contact time, viability was determined. At > or = 1%, organic matter compromised the activity of each concentration of tea tree oil against Staphylococcus aureus and C. albicans. At 10% or more, organic matter compromised the activity of each tea tree oil concentration against Pseudomonas aeruginosa. Organic matter affected 1 and 2% tea tree oil, but not 4 and 8%, against Escherichia coli. In conclusion, organic matter and surfactants compromise the antimicrobial activity of tea tree oil, although these effects vary between organisms.
Shepherd, Mervyn; Savins, Dale; Dowell, Ashley; Morrow, Samantha; Allen, Gareth; Southwell, Ian
Methyl eugenol is a natural phenylpropanoid compound found in a wide range of plants used for food, flavouring, cosmetics and health-care. As a suspected rodent carcinogen, methyl eugenol may also be harmful to humans when present in significant concentrations. Consequently, its level has been restricted in some foodstuffs and cosmetics for some markets. In order to assess the potential to breed uniformly low methyl eugenol cultivars for an essential oil crop, tea tree, the source of "Oil of Melaleuca, terpinene-4-ol type", we examine levels in individual trees (n= 30) from two geographic regions and six terpene chemotypes. Overall, methyl eugenol levels were low in this species (Mean (SD) 354 (239) ppm n=30), much lower than levels predicted to be of toxicological concern. Within each chemotype, there was a lack of evidence for correlations between terpenoid constituents and methyl eugenol levels. Further support for the independence of methyl eugenol and terpene biosynthesis was evident from similar mean levels in selected (Mean (SD) 586 (339) ppm n=12) and undomesticated M. alternifolia trees (Mean (SD) 480 (299) ppm n=5) with terpinen-4-ol type oils. By contrast, methyl eugenol level varied by geographic origin and chemotype. Trees from the upland region, where there is a prevalence of terpinolene type trees, had lower average methyl eugenol levels than trees from the coastal region, where there is a prevalence of terpinen-4-ol and 1,8-cineole type trees. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
Hammer, K A; Carson, C F; Riley, T V
The in-vitro activity of a range of essential oils, including tea tree oil, against the yeast candida was examined. Of the 24 essential oils tested by the agar dilution method against Candida albicans ATCC 10231, three did not inhibit C. albicans at the highest concentration tested, which was 2.0% (v/v) oil. Sandalwood oil had the lowest MIC, inhibiting C. albicans at 0.06%. Melaleuca alternifolia (tea tree) oil was investigated for activity against 81 C. albicans isolates and 33 non-albicans Candida isolates. By the broth microdilution method, the minimum concentration of oil inhibiting 90% of isolates for both C. albicans and non-albicans Candida species was 0.25% (v/v). The minimum concentration of oil killing 90% of isolates was 0.25% for C. albicans and 0.5% for non-albicans Candida species. Fifty-seven Candida isolates were tested for sensitivity to tea tree oil by the agar dilution method; the minimum concentration of oil inhibiting 90% of isolates was 0.5%. Tests on three intra-vaginal tea tree oil products showed these products to have MICs and minimum fungicidal concentrations comparable to those of non-formulated tea tree oil, indicating that the tea tree oil contained in these products has retained its anticandidal activity. These data indicate that some essential oils are active against Candida spp., suggesting that they may be useful in the topical treatment of superficial candida infections.
Callander, J T; James, P J
Laboratory studies were conducted to assess the effect of tea tree oil (TTO) from Melaleuca alternifolia (terpinen-4-ol chemotype) against different stages of the Australian sheep blowfly Lucilia cuprina. When applied to wool, 3% TTO formulation repelled gravid female L. cuprina and prevented oviposition for six weeks. Formulations containing 1% TTO caused 100% mortality of L. cuprina eggs and 1st instar larvae and 2.5% TTO caused mortality of most second and third instar larvae in agar feeding assays. In experiments where third instar larvae were dipped in TTO formulations for 60s, concentrations of up to 50% TTO gave less than 50% kill. TTO at concentrations of 0.5%, 2% and 5% was strongly repellent to third instar larvae and caused them to evacuate treated areas. Inclusion of TTO in formulations with diazinon, ivermectin and boric acid reduced mortality in comparison with the larvicides used alone, at least partially because of avoidance behaviour stimulated by the TTO. Addition of TTO to wound treatments may aid in wound protection and myiasis resolution by preventing oviposition by L. cuprina adults, insecticidal action against L. cuprina eggs and larvae, stimulating larvae to leave the wound and through antimicrobial and anti-inflammatory properties that aid in wound healing.
Kim, Hyun-Jin; Chen, Feng; Wu, Changqing; Wang, Xi; Chung, Hau Yin; Jin, Zhengyu
Antioxidant activity of Australian tea tree (Melaleuca alternifolia) oil (TTO) was determined using two different assays. In the 2,2-diphenyl-1-picrylhydrazyl assay, 10 microL/mL crude TTO in methanol had approximately 80% free radical scavenging activity, and in the hexanal/hexanoic acid assay, 200 microL/mL crude TTO exhibited 60% inhibitory activity against the oxidation of hexanal to hexanoic acid over 30 days. These results were equivalent to the antioxidant activities of 30 mM butylated hydroxytoluene in both tests at the same experimental conditions. This indicated that the TTO could be a good alternative antioxidant. Inherent antioxidants, i.e., alpha-terpinene, alpha-terpinolene, and gamma-terpinene, in the crude TTO were separated and identified chromatographically using silica gel open chromatography, C(18)-high-pressure liquid chromatography, and gas chromatography-mass spectrometry. Their antioxidant activities decreased in the following order in both assays: alpha-terpinene > alpha-terpinolene > gamma-terpinene.
James, P J; Callander, J T
Tea tree oil (TTO) from the Australian native plant Melaleuca alternifolia has wide ranging bio-active properties, including insecticidal and repellent activity against arthropods. Furthermore, composition of commercially available Australian TTO is specified under an International Organization for Standardization standard (ISO 4730), reducing the potential for variable effects often noted with botanical pesticides. The effect of TTO, meeting the ISO standard for terpinen-4-ol chemotype, was tested against sheep lice (Bovicola ovis Schrank) in a series of laboratory studies. Immersion of wool for 60s in formulations containing concentrations of 1% TTO and above caused 100% mortality of adult lice and eggs. Exposure to vapours from TTO, delivered as droplets in fumigation chambers and when applied to wool also caused high mortality in both lice and eggs. The main active component of TTO in the fumigant tests was terpinen-4-ol. Treated surface assays and tests with wool where the formulation was allowed to dry before exposure of lice indicated low persistence. These studies demonstrate that TTO is highly toxic to sheep lice and active at concentrations that suggest potential for the development of TTO-based ovine lousicides.
Hammer, K A; Carson, C F; Riley, T V; Nielsen, J B
The essential oil of Melaleuca alternifolia, also known as tea tree or melaleuca oil, is widely available and has been investigated as an alternative antimicrobial, anti-inflammatory and anti-cancer agent. While these properties are increasingly well characterised, relatively limited data are available on the safety and toxicity of the oil. Anecdotal evidence from almost 80 years of use suggests that the topical use of the oil is relatively safe, and that adverse events are minor, self-limiting and occasional. Published data indicate that TTO is toxic if ingested in higher doses and can also cause skin irritation at higher concentrations. Allergic reactions to TTO occur in predisposed individuals and may be due to the various oxidation products that are formed by exposure of the oil to light and/or air. Adverse reactions may be minimised by avoiding ingestion, applying only diluted oil topically and using oil that has been stored correctly. Data from individual components suggest that TTO has the potential to be developmentally toxic if ingested at higher doses, however, TTO and its components are not genotoxic. The limited ecotoxicity data available indicate that TTO is toxic to some insect species but more studies are required.
Greay, Sara J; Ireland, Demelza J; Kissick, Haydn T; Heenan, Peter J; Carson, Christine F; Riley, Thomas V; Beilharz, Manfred W
Systemic toxicity coupled with long treatment regimes of approved topical chemotherapeutic agents such as imiquimod and 5-fluorouracil (5-FU) are limiting. There is now more focus on the potential use of topical terpene agents as skin cancer treatments. Here, we show for the first time that topical Melaleuca alternifolia (tea tree) oil (TTO), abundant in terpenes, has in vivo antitumour activity. Topical TTO formulations applied to immunocompetent tumour-bearing mice were assessed for antitumour efficacy by monitoring tumour growth and by histological analysis following treatment. Four, daily, topical treatments of 10% TTO/DMSO regressed subcutaneous AE17 mesotheliomas in mice for a period of 10 days and significantly retarded the growth of subcutaneous B16-F10 melanomas. The antitumour effect of topical 10% TTO/DMSO was accompanied by skin irritation similar to other topical chemotherapeutic agents, but unlike other approved topical agents, quickly and completely resolved. Furthermore, we show that topical 10% TTO/DMSO caused an influx of neutrophils and other immune effector cells in the treated area, with no evidence of systemic toxicity. TTO combined with an effective carrier significantly inhibited the growth of aggressive, subcutaneous, chemo-resistant tumours in immunocompetent mice. Taken together, these findings highlight the potential of topical TTO as an alternative topical antitumour treatment.
Nenoff, P; Haustein, U F; Brandt, W
The in vitro antifungal activity of tea oil, the essential oil of Melaleuca alternifolia, has been evaluated against 26 strains of various dermatophyte species, 54 yeasts, among them 32 strains of Candida albicans and other Candida sp. as well as 22 different Malassezia furfur strains. Minimum inhibitory concentrations (MIC) of tea tree oil were measured by agar dilution technique. Tea tree oil was found to be able to inhibit growth of all clinical fungal isolates. For the investigated dermatophytes MIC values from 1,112.5 to 4,450.0 micrograms/ml with a geometric mean of 1,431.5 micrograms/ml were demonstrated. Both C. albicans strains and the other strains belonging to the genus Candida and Trichosporon appeared to be slightly less susceptible to tea tree oil in vitro. However, their MIC values, which varied from 2,225.0 to 4,450.0 micrograms/ml (geometric mean 4,080 micrograms/ml), indicated moderate susceptibility to the essential oil of M. alternifolia. The lipophilic yeast M. furfur seemed to be most susceptible to tea tree oil. MIC values between 556.2 and 4,450.0 micrograms/ml (geometric mean 1,261.5 micrograms/ml) were found against the tested M. furfur strains. However, when calculated as percentage tea tree oil of the agar, the above-mentioned concentrations correspond to 0.5-0.44% tea tree oil content. These values are far below the usual relatively high therapeutic concentrations of the agent; approximately 5-10% solution or even the concentrated essential oil are used for external treatment. In comparison with tea tree oil, in vitro susceptibility against miconazole, an established topical antifungal, was tested. As expected, very low MIC values for miconazole were found for dermatophytes (geometric mean 0.2 microgram/ml), yeasts (geometric mean 1.0 microgram/ml), and M. furfur (geometric mean 2.34 micrograms/ml). It is suggested that the in vivo effect of tea tree oil ointment in the therapy of fungal infections of the skin and mucous membranes as
Thomsen, Natalie A; Hammer, Katherine A; Riley, Thomas V; Van Belkum, Alex; Carson, Christine F
The aim of this study was to seek additional data on the antimicrobial susceptibility of Staphylococcus spp. after habituation to low levels of the topical antimicrobial agent tea tree (Melaleuca alternifolia) oil. Meticillin-susceptible Staphylococcus aureus (MSSA), meticillin-resistant S. aureus (MRSA) and coagulase-negative staphylococci (CoNS) were habituated to 0.075% tea tree oil for 3 days. Subsequently, the susceptibility of five isolates each of MSSA, MRSA and CoNS to fusidic acid, mupirocin, chloramphenicol, linezolid and vancomycin was determined by Etest, and susceptibility to tea tree oil, terpinen-4-ol, carvacrol and triclosan was determined by agar dilution. Following habituation to 0.075% tea tree oil, antimicrobial MICs differed between control and habituated isolates on 33 occasions (out of a possible 150), with MICs being higher in habituated isolates on 22 occasions. Using clinical breakpoint criteria, one MSSA isolate changed susceptibility category from vancomycin-susceptible (MIC=2 μg/mL) to intermediate susceptibility (MIC=3 μg/mL) after habituation in one of two replicates. For the non-antibiotic antimicrobial agents, MICs of habituated and control isolates differed on 12 occasions (out of a possible 120); 10 occasions in MRSA and 2 occasions in MSSA. MICs were higher for habituated isolates on five occasions. However, all the differences were one serial dilution only and were not regarded as significant. Habituation to sublethal concentrations of tea tree oil led to minor changes in MICs of antimicrobial agents, only one of which may have been clinically relevant. There is no evidence to suggest that tea tree oil induces resistance to antimicrobial agents.
Walton, Shelley F; McKinnon, Melita; Pizzutto, Susan; Dougall, Annette; Williams, Edwina; Currie, Bart J
To compare the acaricidal activity of Melaleuca alternifolia (tea tree) oil (TTO) and some of its individual active components on the itch mite Sarcoptes scabiei var hominis. In vitro acaricide sensitivity assessment. The Menzies School of Health Research laboratory, located near the Infectious Diseases Ward of the Royal Darwin Hospital, Australia, where patients are admitted and treated for crusted scabies. Scabies mites (S scabiei var hominis) were collected from a 20-year-old Aboriginal woman admitted to the Royal Darwin Hospital with crusted scabies. Interventions Within 3 hours of collection, scabies mites were placed in continuous direct contact with the TTO products and control acaricides and were observed at regular intervals. Percentage of mites dead at regular observation intervals between 5 minutes and 24 hours during continuous exposure to the TTO products and acaricides. The 5% TTO and active component terpinen-4-ol were highly effective in reducing mite survival times. Statistically significant differences in mite survival curves were observed for 5% TTO, 2.1% terpinen-4-ol, 5% permethrin, and ivermectin (100 microg/g of Emulsifying Ointment British Pharmacopoeia 88). In vivo effectiveness was also observed. Documentation of resistance against antiectoparasitic compounds is increasing. Reported S scabiei treatment failures with lindane, crotamiton, and benzyl benzoate, as well as likely emerging resistance to 5% permethrin and oral ivermectin, are of concern and advocate for the identification and development of novel acaricidal drugs. Tea tree oil is a membrane-active biocide extracted from the tree M alternifolia. It is a principal antimicrobial in a wide range of pharmaceuticals sold in Australia, with the main active component being oxygenated terpenoids. The results suggest that TTO has a potential role as a new topical acaricide and confirm terpinen-4-ol as the primary active component.
Iori, A; Grazioli, D; Gentile, E; Marano, G; Salvatore, G
The aim of the study was to examine the acaricidal effect of essential oil of Melaleuca alternifolia (tea tree oil, TTO) at different doses (4, 6, 8 and 10 microl) and for different exposure times (30, 60, 90 and 120 min) on nymphs of Ixodes ricinus. A dose of 8 microl TTO was lethal for more than 70% of ticks when inhaled and this effect was enhanced when the dose was increased to 10 microl (> 80%). The effect was correlated with the duration of exposure of ticks to TTO, with a significant effect being observed after 90 min exposure. The findings show that TTO has acaricidal properties and could be extremely useful in controlling ticks that are efficient vectors of pathogens.
Raymond, Carolyn A; Davies, Noel W; Larkman, Tony
Tea tree oil distilled from Melaleuca alternifolia has widespread use in the cosmetic industry as an antimicrobial as well as for other functions in topical products. Concerns were first raised by the European Commission's Scientific Committee on Consumer Products in 2004 about the level of the potentially carcinogenic phenylpropanoid compound methyl eugenol in tea tree oil. Limits on oil content in different types of cosmetic products were set based on a reported upper level of 0.9% methyl eugenol in the oil. A previous publication indicated that these levels were based on oil from a Melaleuca species not used in the commercial production of oil. Even the highest recorded levels in Melaleuca alternifolia, the overwhelmingly most common species used, were ∼15 times less than this, meaning that more oil could be safely used in the products. The current study, including details on methodology and reproducibility, extends that work across a suite of 57 plantation-sourced oils from a range of geographical locations and production years, as well as many Australian and international commercial oils. Lower levels of methyl eugenol in oils of known provenance were confirmed, with a recorded range of 160-552 ppm and a mean of 337 ppm. Analysis of variance showed methyl eugenol levels in Australian plantation oils to be correlated to the geographical region but not to the year of production. Average methyl eugenol levels in commercial oils were significantly lower, and these samples were divided into an authentic group and a group that were suspected of being adulterated based on an independent test. Authentic commercial oils had similar levels of methyl eugenol to Australian provenance material, whilst the oils classed as suspect had significantly lower levels.
Carson, C F; Hammer, K A; Riley, T V
Complementary and alternative medicines such as tea tree (melaleuca) oil have become increasingly popular in recent decades. This essential oil has been used for almost 100 years in Australia but is now available worldwide both as neat oil and as an active component in an array of products. The primary uses of tea tree oil have historically capitalized on the antiseptic and anti-inflammatory actions of the oil. This review summarizes recent developments in our understanding of the antimicrobial and anti-inflammatory activities of the oil and its components, as well as clinical efficacy. Specific mechanisms of antimicrobial and anti-inflammatory action are reviewed, and the toxicity of the oil is briefly discussed.
Carson, C. F.; Hammer, K. A.; Riley, T. V.
Complementary and alternative medicines such as tea tree (melaleuca) oil have become increasingly popular in recent decades. This essential oil has been used for almost 100 years in Australia but is now available worldwide both as neat oil and as an active component in an array of products. The primary uses of tea tree oil have historically capitalized on the antiseptic and anti-inflammatory actions of the oil. This review summarizes recent developments in our understanding of the antimicrobial and anti-inflammatory activities of the oil and its components, as well as clinical efficacy. Specific mechanisms of antimicrobial and anti-inflammatory action are reviewed, and the toxicity of the oil is briefly discussed. PMID:16418522
Ergin, A; Arikan, S
The in vitro activity of fluconazole and Melaleuca alternifolia (tea tree) oil was evaluated against 99 vaginal Candida strains by the broth microdilution and disc diffusion methods. The microdilution method was performed in accordance with NCCLS-M27A guidelines. An investigational method was used for the disc diffusion test. Fluconazole and tea tree oil minimum inhibitory concentrations (MICs) obtained at 48 h tended to increase 1- to 2-fold or remain the same compared to 24 h readings for most of the isolates tested. C. krusei and C. norvegensis had significantly higher MICs and smaller inhibition zones for fluconazole compared to other species. Tea tree oil MICs were found to be similar, in general, for all Candida spp. tested. The geometric mean MIC of tea tree oil for all isolates was 2.2% (range, 0.25-4%) at 24 h and 3.0% (range, 1-8%) at 48 h. Tea tree oil mean inhibition zone diameter was 24 mm (range, 14-42 mm) at 24 h and 15.8 mm (range, 10-35 mm) at 48 h. In vitro activity of tea tree oil against fluconazole-resistant Candida strains was of particular interest. The isolates had similar tea tree oil MICs and inhibition zone diameters regardless of their fluconazole susceptibility profile. Tea tree oil MIC ranges (inhibition zone diameter ranges) were 2-4% (12-21 mm) and 2% (35 mm) at 48 h for C. krusei and C. norvegensis, respectively. These results suggest that tea tree oil MICs of the fluconazole-resistant isolates are comparable to those of fluconazole-susceptible isolates. This in vitro finding is promising for potential use of topical tea tree oil formulations in the treatment of candidiasis due to fluconazole-resistant strains.
Baldissera, Matheus D; Da Silva, Aleksandro S; Oliveira, Camila B; Vaucher, Rodrigo A; Santos, Roberto C V; Duarte, Thiago; Duarte, Marta M M F; França, Raqueli T; Lopes, Sonia T A; Raffin, Renata P; Boligon, Aline A; Athayde, Margareth L; Stefani, Lenita M; Monteiro, Silvia G
This study aimed to evaluate the effect of tea tree oil (TTO - Melaleuca alternifolia) on hepatic and renal functions, and the immune response of rats infected by Trypanosoma evansi. A pilot study has shown that rats treated with TTO orally (1 ml kg(-1)) had increased survival rate without curative effect. In order to verify if increased longevity was related to a better immune response against T. evansi when using tea tree oil, a second experiment was conducted. Thus, twenty-four rats were divided into four groups. The groups A and B were composed of uninfected animals, and the groups C and D had rats experimentally infected by T. evansi. Animals from the groups B and D were treated orally with TTO (1 ml kg(-1)) for three days. Blood samples were collected to verify humoral response analysis for immunoglobulins (IgA, IgM, IgE, and IgG) and cytokines (TNF-α, INF-γ, IL-1, IL-6, IL-4, and IL-10) at days 0, 3, 5 and 15 post-infection (PI). TTO treatment caused changes in the immunoglobulins and cytokines profile, as well as the course of T. evansi infection in rats. It was found that the TTO was not toxic, i.e., hepatic and renal functions were not affected. Therefore, it is possible to conclude that TTO influences the levels of inflammatory mediators and has trypanocidal effect, increasing life expectancy of rats infected by T. evansi. Copyright © 2014 Elsevier Ltd. All rights reserved.
Ireland, Demelza J; Greay, Sara J; Hooper, Cornelia M; Kissick, Haydn T; Filion, Pierre; Riley, Thomas V; Beilharz, Manfred W
Melaleuca alternifolia (tea tree) oil (TTO) applied topically in a dilute (10%) dimethyl sulphoxide (DMSO) formulation exerts a rapid anti-cancer effect after a short treatment protocol. Tumour clearance is associated with skin irritation mediated by neutrophils which quickly and completely resolves upon treatment cessation. To examine the mechanism of action underlying the anti-cancer activity of TTO. Immune cell changes in subcutaneous tumour bearing mice in response to topically applied TTO treatments were assessed by flow cytometry and immunohistochemistry. Direct cytotoxicity of TTO on tumour cells in vivo was assessed by transmission electron microscopy. Neutrophils accumulate in the skin following topical 10% TTO/DMSO treatment but are not required for tumour clearance as neutrophil depletion did not abrogate the anti-cancer effect. Topically applied 10% TTO/DMSO, but not neat TTO, induces an accumulation and activation of dendritic cells and an accumulation of T cells. Although topical application of 10% TTO/DMSO appears to activate an immune response, anti-tumour efficacy is mediated by a direct effect on tumour cells in vivo. The direct cytotoxicity of TTO in vivo appears to be associated with TTO penetration. Future studies should focus on enhancing the direct cytotoxicity of TTO by increasing penetration through skin to achieve a higher in situ terpene concentration. This coupled with boosting a more specific anti-tumour immune response will likely result in long term clearance of tumours. Copyright © 2012 Japanese Society for Investigative Dermatology. Published by Elsevier Ireland Ltd. All rights reserved.
Effects of Melaleuca alternifolia (tea tree) essential oil and the major monoterpene component terpinen-4-ol on the development of single- and multistep antibiotic resistance and antimicrobial susceptibility.
Hammer, Katherine A; Carson, Christine F; Riley, Thomas V
This study examined the effect of subinhibitory Melaleuca alternifolia (tea tree) essential oil on the development of antibiotic resistance in Staphylococcus aureus and Escherichia coli. Frequencies of single-step antibiotic-resistant mutants were determined by inoculating bacteria cultured with or without subinhibitory tea tree oil onto agar containing 2 to 8 times the MIC of each antibiotic and with or without tea tree oil. Whereas most differences in resistance frequencies were relatively minor, the combination of kanamycin and tea tree oil yielded approximately 10-fold fewer resistant E. coli mutants than kanamycin alone. The development of multistep antibiotic resistance in the presence of tea tree oil or terpinen-4-ol was examined by culturing S. aureus and E. coli isolates daily with antibiotic alone, antibiotic with tea tree oil, and antibiotic with terpinen-4-ol for 6 days. Median MICs for each antibiotic alone increased 4- to 16-fold by day 6. Subinhibitory tea tree oil or terpinen-4-ol did not greatly alter results, with day 6 median MICs being either the same as or one concentration different from those for antibiotic alone. For tea tree oil and terpinen-4-ol alone, day 6 median MICs had increased 4-fold for S. aureus (n = 18) and 2-fold for E. coli (n = 18) from baseline values. Lastly, few significant changes in antimicrobial susceptibility were seen for S. aureus and S. epidermidis isolates that had been serially subcultured 14 to 22 times with subinhibitory terpinen-4-ol. Overall, these data indicate that tea tree oil and terpinen-4-ol have little impact on the development of antimicrobial resistance and susceptibility.
Effects of Melaleuca alternifolia (Tea Tree) Essential Oil and the Major Monoterpene Component Terpinen-4-ol on the Development of Single- and Multistep Antibiotic Resistance and Antimicrobial Susceptibility
Carson, Christine F.; Riley, Thomas V.
This study examined the effect of subinhibitory Melaleuca alternifolia (tea tree) essential oil on the development of antibiotic resistance in Staphylococcus aureus and Escherichia coli. Frequencies of single-step antibiotic-resistant mutants were determined by inoculating bacteria cultured with or without subinhibitory tea tree oil onto agar containing 2 to 8 times the MIC of each antibiotic and with or without tea tree oil. Whereas most differences in resistance frequencies were relatively minor, the combination of kanamycin and tea tree oil yielded approximately 10-fold fewer resistant E. coli mutants than kanamycin alone. The development of multistep antibiotic resistance in the presence of tea tree oil or terpinen-4-ol was examined by culturing S. aureus and E. coli isolates daily with antibiotic alone, antibiotic with tea tree oil, and antibiotic with terpinen-4-ol for 6 days. Median MICs for each antibiotic alone increased 4- to 16-fold by day 6. Subinhibitory tea tree oil or terpinen-4-ol did not greatly alter results, with day 6 median MICs being either the same as or one concentration different from those for antibiotic alone. For tea tree oil and terpinen-4-ol alone, day 6 median MICs had increased 4-fold for S. aureus (n = 18) and 2-fold for E. coli (n = 18) from baseline values. Lastly, few significant changes in antimicrobial susceptibility were seen for S. aureus and S. epidermidis isolates that had been serially subcultured 14 to 22 times with subinhibitory terpinen-4-ol. Overall, these data indicate that tea tree oil and terpinen-4-ol have little impact on the development of antimicrobial resistance and susceptibility. PMID:22083482
Garozzo, A; Timpanaro, R; Stivala, A; Bisignano, G; Castro, A
Our previous study demonstrated that Melaleuca alternifolia (tea tree) oil (TTO) had an interesting antiviral activity against Influenza A in MDCK cells. In fact, when we tested TTO and some of its components, we found that TTO had an inhibitory effect on influenza virus replication at doses below the cytotoxic dose; terpinen-4-ol, terpinolene, and alfa-terpineol were the main active components. The aim of this study was to investigate the mechanism of action of TTO and its active components against Influenza A/PR/8 virus subtype H1N1 in MDCK cells. None of the test compounds showed virucidal activity nor any protective action for the MDCK cells. Thus, the effect of TTO and its active components on different steps of the replicative cycle of influenza virus was studied by adding the test compounds at various times after infection. These experiments revealed that viral replication was significantly inhibited if TTO was added within 2h of infection, indicating an interference with an early step of the viral replicative cycle of influenza virus. The influence of the compound on the virus adsorption step, studied by the infective center assay, indicated that TTO did not interfere with cellular attachment of the virus. TTO did not inhibit influenza virus neuraminidase activity, as shown by the experiment measuring the amount of 4-methylumbelliferone, cleaved by the influenza virus neuraminidase from the fluorogenic substrate 2'-O-(4-methylumbelliferyl)-N-acetylneuraminic acid. The effect of TTO on acidification of cellular lysosomes was studied by vital staining with acridine orange using bafilomycin A1 as positive control. The treatment of cells with 0.01% (v/v) of TTO at 37°C for 4h before staining inhibited the acridine orange accumulation in acid cytoplasmic vesicles, indicating that TTO could inhibit viral uncoating by an interference with acidification of intralysosomal compartment.
Mantil, Elisabeth; Daly, Grace; Avis, Tyler J
There has been increased interest surrounding the use of tea tree oil (TTO) as a natural antimicrobial. In this study, the antimicrobial activity of TTO and its components were investigated in vitro and in a predominantly lipid-based personal care formulation. In vitro, TTO showed minimal inhibitory concentrations of 0.2% (for Saccharomyces cerevisiae and Pythium sulcatum), 0.4% (for Escherichia coli, Bacillus subtilis, and Rhizopus stolonifer), and 0.8% (for Botrytis cinerea). TTO at 0.08%-0.8% was often as efficient as parabens. Comparison of the antimicrobial activities of TTO components showed that terpinen-4-ol and γ-terpinene were generally most effective in inhibiting microbial growth. TTO activity in a personal care product was evaluated through air and water exposure, artificial inoculation, and shelf life studies. While TTO did not increase shelf life of unopened products, it decreased microbial load in products exposed to water and air. Results from this study support that antimicrobial activity of TTO can be attributed to varying levels of its components and that low levels of TTO were effective in reducing microbial growth during the use of the product. This study showed that TTO can act as a suitable preservative system within an oil-based formulation.
Kwieciński, Jakub; Eick, Sigrun; Wójcik, Kinga
Tea tree oil (TTO) is known for its antimicrobial activity. In this study, we determined whether TTO is effective against Staphylococcus aureus in biofilms and how TTO activity is affected by the S. aureus growth phase. All clinical strains tested were killed by TTO both as planktonic cells and as biofilms. The minimum biofilm eradication concentration was usually two times higher than the minimum bactericidal concentration, yet it was never higher than 1% v/v. The fastest killing of biofilm occurred during the first 15min of contact with TTO and was not influenced by increasing TTO concentration above 1% v/v. Planktonic stationary phase cells exhibited decreased susceptibility to TTO compared with exponential phase cells. The killing rate for stationary phase cells was also less affected by increasing TTO concentration than that for exponential phase cells. These data show that TTO efficiently kills S. aureus in the stationary growth phase and within biofilms and is therefore a promising tool for S. aureus eradication.
Syed, T A; Qureshi, Z A; Ali, S M; Ahmad, S; Ahmad, S A
The prevalence of onychomycosis, a superficial fungal infection that destroys the entire nail unit, is rising, with no satisfactory cure. The objective of this randomized, double-blind, placebo-controlled study was to examine the clinical efficacy and tolerability of 2% butenafine hydrochloride and 5% Melaleuca alternifolia oil incorporated in a cream to manage toenail onychomycosis in a cohort. Sixty outpatients (39 M, 21 F) aged 18-80 years (mean 29.6) with 6-36 months duration of disease were randomized to two groups (40 and 20), active and placebo. After 16 weeks, 80% of patients using medicated cream were cured, as opposed to none in the placebo group. Four patients in the active treatment group experienced subjective mild inflammation without discontinuing treatment. During follow-up, no relapse occurred in cured patients and no improvement was seen in medication-resistant and placebo participants.
Tankeu, Sidonie; Vermaak, Ilze; Kamatou, Guy; Viljoen, Alvaro
Tea tree oil (TTO) is an important commercial oil which has found application in the flavour, fragrance and cosmetic industries. The quality is determined by the relative concentration of its major constituents: 1,8-cineole, terpinen-4-ol, α-terpineol, α-terpinene, terpinolene, γ-terpinene and limonene. Gas chromatography coupled to mass spectrometry (GC-MS) is traditionally used for qualitative and quantitative analyses but is expensive and time consuming. To evaluate the use of vibrational spectroscopy in tandem with chemometric data analysis as a fast and low-cost alternative method for the quality control of TTO. Spectral data were acquired in both the mid-infrared (MIR) and near infrared (NIR) wavelength regions and reference data obtained using GC-MS with flame ionisation detection (FID). Principal component analysis (PCA) was used to investigate the data by observing clustering and identifying outliers. Partial least squares (PLS) multivariate calibration models were constructed for the quantification of the seven major constituents. High correlation coefficients (R(2) ) of ≥ 0.75 were obtained for the seven major compounds and 1,8-cineole showed the best correlation coefficients for both MIR and NIR data (R(2) = 0.97 and 0.95, respectively). Low values were obtained for the root mean square error of estimation (RMSEE) and root mean square error of prediction (RMSEP) values thereby confirming accuracy. The accurate prediction of the external dataset after introduction into the models confirmed that both MIR and NIR spectroscopy are valuable methods for quantification of the major compounds of TTO when compared with the reference data obtained using GC-MS. Copyright © 2013 John Wiley & Sons, Ltd. Copyright © 2013 John Wiley & Sons, Ltd.
Pisseri, F; Bertoli, A; Nardoni, S; Pinto, L; Pistelli, L; Guidi, G; Mancianti, F
Dermatophytes are a group of keratinophilic and keratinolytic molds, some of which are responsible for ringworm. Among them Trichophyton equinum, which mostly infects equids, can cause extensive outbreaks in stud farms. The conventional treatment of equine trichophytosis is topic, based upon medicated shampoos to reduce the spread of infection among the animals. Nevertheless the popularity of phytotherapy is at an all-time peak, and the interest for natural alternatives or complements to conventional drug therapy is challenging both in human and veterinary field. Among herbal remedia Tea Tree Oil (TTO) shows a wide range of antimicrobial activities. A randomized open clinical trial was carried out on 60 thoroughbred breeding horses affected by equine ringworm. The animals were randomly divided into 2 groups of 30 subjects. Diagnostic criteria were the presence of clinical signs and positive T. equinum culture. Specificity control using TTO mixture in 5 not dermatophyte affected animals was achieved also. The antimycotic activity against T. equinum of a mixture containing 25% TTO in sweet almond oil, was evaluated in vivo treating 30 subjects, the others were administered enilconazole 2% solution. The animals of both groups were topically treated twice a day for 15 days with a 25% mixture of TTO diluted in sweet almond oil and every 3 days, four times with enilconazole rinses, respectively. The clinical and mycological outcome were evaluated at day 30 from the start of the treatments. Data analysis was performed by chi square test. All the treated animals showed complete clinical and aetiological healing. Part of control subjects also, showed an improvement and none of them exacerbate the lesions. This therapeutic protocol appears to be effective and versatile, being applicable immediately after physical examination, prior to have the laboratory response. It could be an alternative for practitioners interested in herbal medicines, contributing to fulfill the gap
Baldissera, Matheus D; Da Silva, Aleksandro S; Oliveira, Camila B; Santos, Roberto C V; Vaucher, Rodrigo A; Raffin, Renata P; Gomes, Patrícia; Dambros, Maria G C; Miletti, Luiz C; Boligon, Aline A; Athayde, Margareth L; Monteiro, Silvia G
This study aimed to evaluate the Trypanosoma evansi susceptibility to tea tree oil (TTO - Melaleuca alternifolia) and tea tree oil nanocapsules (TTO nanocapsules) in vitro and in vivo tests. In vitro, we observed a mortality curve of trypomastigotes proportional to dose, i.e., the TTO and TTO nanocapsules have trypanocidal effect. Treatment with TTO in vivo was assessed in experiments (I and II). For Experiment I, T. evansi infected mice were treated with TTO and/or combinations of essential oil with chemotherapy (diminazene aceturate - D.A.). Treatment with TTO at a dose of 1mLkg(-1) was able to extend animal longevity, but had no curative efficacy. However, when TTO was combined with D.A. a disease curative efficacy of 100% for disease was observed, a much better result than the D.A. treatment (33.3%). In Experiment II, T. evansi infected mice were treated with TTO nanocapsules with doses of 0.3, 0.6 and 0.9mLkg(-1). Animals treated with 0.9mLkg(-1) showed higher longevity however without curative effect. Active compounds present in natural products, such as M. alternifolia, may potentiate the treatment of trypanosomosis when associated with other trypanocidal drugs. Copyright © 2014 Elsevier Inc. All rights reserved.
Carson, Christine F; Mee, Brian J; Riley, Thomas V
The essential oil of Melaleuca alternifolia (tea tree) has broad-spectrum antimicrobial activity. The mechanisms of action of tea tree oil and three of its components, 1,8-cineole, terpinen-4-ol, and alpha-terpineol, against Staphylococcus aureus ATCC 9144 were investigated. Treatment with these agents at their MICs and two times their MICs, particularly treatment with terpinen-4-ol and alpha-terpineol, reduced the viability of S. aureus. None of the agents caused lysis, as determined by measurement of the optical density at 620 nm, although cells became disproportionately sensitive to subsequent autolysis. Loss of 260-nm-absorbing material occurred after treatment with concentrations equivalent to the MIC, particularly after treatment with 1,8-cineole and alpha-terpineol. S. aureus organisms treated with tea tree oil or its components at the MIC or two times the MIC showed a significant loss of tolerance to NaCl. When the agents were tested at one-half the MIC, only 1,8-cineole significantly reduced the tolerance of S. aureus to NaCl. Electron microscopy of terpinen-4-ol-treated cells showed the formation of mesosomes and the loss of cytoplasmic contents. The predisposition to lysis, the loss of 260-nm-absorbing material, the loss of tolerance to NaCl, and the altered morphology seen by electron microscopy all suggest that tea tree oil and its components compromise the cytoplasmic membrane.
Calcabrini, Annarica; Stringaro, Annarita; Toccacieli, Laura; Meschini, Stefania; Marra, Manuela; Colone, Marisa; Salvatore, Giuseppe; Mondello, Francesca; Arancia, Giuseppe; Molinari, Agnese
The search for innovative therapeutic approaches based on the use of new substances is gaining more interest in clinical oncology. In this in vitro study the potential anti-tumoral activity of tea tree oil, distilled from Melaleuca alternifolia, was analyzed against human melanoma M14 WT cells and their drug-resistant counterparts, M14 adriamicin-resistant cells. Both sensitive and resistant cells were grown in the presence of tea tree oil at concentrations ranging from 0.005 to 0.03%. Both the complex oil (tea tree oil) and its main active component terpinen-4-ol were able to induce caspase-dependent apoptosis of melanoma cells and this effect was more evident in the resistant variant cell population. Freeze-fracturing and scanning electron microscopy analyses suggested that the effect of the crude oil and of the terpinen-4-ol was mediated by their interaction with plasma membrane and subsequent reorganization of membrane lipids. In conclusion, tea tree oil and terpinen-4-ol are able to impair the growth of human M14 melanoma cells and appear to be more effective on their resistant variants, which express high levels of P-glycoprotein in the plasma membrane, overcoming resistance to caspase-dependent apoptosis exerted by P-glycoprotein-positive tumor cells.
Bagg, Jeremy; Jackson, Margaret S; Petrina Sweeney, M; Ramage, Gordon; Davies, Andrew N
Yeasts that are resistant to azole antifungal drugs are increasingly isolated from the mouths of cancer patients suffering from oral fungal infections. Tea tree oil is an agent possessing antimicrobial properties that may prove useful in the prevention and management of infections caused by these organisms. In this study, 301 yeasts isolated from the mouths of 199 patients suffering from advanced cancer were examined by an in vitro agar dilution assay for susceptibility to tea tree oil. All of the isolates tested were susceptible, including 41 that were known to be resistant to both fluconazole and itraconazole. Clinical studies of tea tree oil as an agent for the prevention and treatment of oral fungal infections in immunocompromised patients merit consideration.
Sudjana, Aurelia N; Carson, Christine F; Carson, Kerry C; Riley, Thomas V; Hammer, Katherine A
This study investigated the effects of the volatile terpene-rich oil from Melaleuca alternifolia (tea tree oil) on the formation of biofilms and the adhesion of C. albicans cells to both biotic and abiotic surfaces. Biofilm formation on polystyrene was significantly inhibited for 70% of the isolates at the lowest test concentration of 0.016% of tea tree oil (TTO) when quantified by XTT and 40% of isolates when measured by crystal violet staining. Adhesion to polystyrene, quantified by crystal violet staining, was significantly reduced for 3 isolates at 0.031%, 6 isolates at 0.062% and 0.125% and for all 7 isolates at 0.25% TTO. Reductions in adhesion were not due to loss of viability (at concentrations of ≤ 0.125%) or interactions between the TTO and polystyrene. Similarly, adhesion to buccal epithelial and HeLa cells was also significantly reduced in the presence of 0.016-0.062% TTO. Treatment with 0.125% TTO, but not 0.062%, decreased the cell surface hydrophobicity of C. albicans, indicating one potential mechanism by which adhesion may be reduced. These data demonstrate that sub-inhibitory TTO reduces the adhesion of C. albicans to both human cells and polystyrene, inhibits biofilm formation and decreases cell surface hydrophobicity.
Papadopoulos, Chelsea J; Carson, Christine F; Chang, Barbara J; Riley, Thomas V
Using a series of efflux mutants of Pseudomonas aeruginosa, the MexAB-OprM pump was identified as contributing to this organism's tolerance to the antimicrobial agent tea tree (Melaleuca alternifolia) oil and its monoterpene components terpinen-4-ol, 1,8-cineole, and alpha-terpineol. These data show that a multidrug efflux system of P. aeruginosa can extrude monoterpenes and related alcohols.
Pharmacological and antimicrobial studies on different tea-tree oils (Melaleuca alternifolia, Leptospermum scoparium or Manuka and Kunzea ericoides or Kanuka), originating in Australia and New Zealand.
Lis-Balchin, M; Hart, S L; Deans, S G
Three different species of Myrtaceae growing in Australia and New Zealand are known as 'Tea-tree': the Australian Tea tree (Melaleuca alternifolia), the New Zealand Manuka (Leptospermum scoparium) and Kanuka (Kunzea ericoides). All three essential oils are used by aromatherapists, although only Melaleuca has been tested for toxicity, and its antimicrobial effects studied. The pharmacology and antimicrobial activity of the three 'tea-tree' oils was determined using guinea-pig ileum, skeletal muscle (chick biventer muscle and the rat phrenic nerve diaphragm) and also rat uterus in vitro. Differences were shown between the three essential oils in their action on smooth muscle: Manuka had a spasmolytic action, while Kanuka and Melaleuca had an initial spasmogenic action. Using the diaphragm, Manuka and Melaleuca decreased the tension and caused a delayed contracture; Kanuka had no activity at the same concentration. The action on chick biventer muscle was, however, similar for all three oils, as was the action on the uterus, where they caused a decrease in the force of the spontaneous contractions. The latter action suggests caution in the use of these essential oils during childbirth, as cessation of contractions could put the baby, and mother, at risk. The comparative antimicrobial activity showed greater differences between different samples of Manuka and Kanuka than Melaleuca samples. The antifungal activity of Kanuka was inversely proportional to its strong antibacterial activity, whilst Manuka displayed a stronger antifungal effect, though not as potent as Melaleuca. The antioxidant activity of Manuka samples was more consistent than that of Kanuka, while Melaleuca showed no activity. The variability in the Manuka and Kanuka essential oils suggests caution in their usage, as does the fact that the oils have not been tested for toxicity.
Hammer, Katherine A; Carson, Christine F; Riley, Thomas V
This study was conducted to determine the frequencies at which single-step mutants resistant to tea tree oil and rifampicin occurred amongst the Gram-positive organisms Staphylococcus aureus, Staphylococcus epidermidis and Enterococcus faecalis. For tea tree oil, resistance frequencies were very low at <10(-9). Single-step mutants resistant to tea tree oil were undetectable at two times the minimum inhibitory concentration (MIC) for S. aureus RN4220 and derivative mutator strains or at 3 x MIC for the remaining S. aureus strains, including a clinical meticillin-resistant S. aureus isolate. Similarly, no mutants were recovered at 2x MIC for S. epidermidis or at 1x MIC for E. faecalis. Resistance frequencies determined in vitro for rifampicin (8 x MIC) ranged from 10(-7) to 10(-8) for all isolates, with the exception of the S. aureus mutator strains, which had slightly higher frequencies. These data suggest that Gram-positive organisms such as Staphylococcus and Enterococcus spp. have very low frequencies of resistance to tea tree oil.
de Souza Silveira Valente, Júlia; de Oliveira da Silva Fonseca, Anelise; Brasil, Carolina Litchina; Sagave, Lauren; Flores, Fernanda Cramer; de Bona da Silva, Cristiane; Sangioni, Luís Antônio; Pötter, Luciana; Santurio, Janio Morais; de Avila Botton, Sônia; Pereira, Daniela Isabel Brayer
Pythium insidiosum is an important aquatic oomycete which can cause pythiosis in both animals and humans. This microorganism shows low susceptibility to antifungal drugs available. This study analyzed the in vitro antimicrobial activity of Melaleuca alternifolia in its free oil (FO) and nanoemulsion (NE) formulations against Brazilian P. insidiosum isolates. The antimicrobial activity evaluation was performed by the broth microdilution method according to CSLI M38-A2 document adapted to phytopharmaceuticals. Twenty-six P. insidiosum isolates were evaluated, and the minimum inhibitory concentration was determined at 100 % growth inhibition. Melaleuca alternifolia essential oil or FO was obtained commercially. The NE containing 1 % M. alternifolia essential oil was prepared by the spontaneous emulsification method. All P. insidiosum isolates evaluated showed minimum inhibitory concentrations (MIC) ranging from 531.5 to 2125 μg/mL for the FO formulation; MIC50 and MIC90 showed values between 1062.5 and 2125 μg/mL, respectively. When the NE formulation was evaluated, MIC values ranged from 132.7 to 2125 μg/mL and both MIC50 and MIC90 corresponded to 1062.5 μg/mL. FO and NE formulations of M. alternifolia showed antimicrobial activity against P. insidiosum. This study demonstrated that M. alternifolia oil can be an additional therapy in pythiosis treatment; however, further studies are needed to evaluate the applicability of the plant essential oils in the treatment of clinical pythiosis.
Ninomiya, Kentaro; Maruyama, Naho; Inoue, Shigeharu; Ishibashi, Hiroko; Takizawa, Toshio; Oshima, Haruyuki; Abe, Shigeru
The therapeutic efficacy of tea tree oil (TTO), Melaleuca alternifolia, and its main component, terpinen-4-ol, were evaluated in a murine oral candidiasis model. Prednisolone -pretreated mice were orally infected with a fluconazole-susceptible (TIMM 2640) or a resistant (TIMM 3163) strain of Candida albicans to induce oral candidiasis. TTO or terpinen-4-ol was administrated with a cotton swab 3 h and 24 h after candida infection. These treatments clearly showed a decrease in the symptom score of tongues and in the viable candida cell number in the oral cavity at 2 d after azole-susceptible C. albicans infection, although the degree of the efficacy was less than that of fluconazole. Even against oral candidiasis caused by azole-resistant C. albicans, TTO and terpinen-4-ol were similarly effective, while fluconazole appeared ineffective. These results suggest that TTO and terpinen-4-ol may have the potential of therapeutic ability for mucosal candidiasis which may also be applicable to C. albicans oral candidiasis induced by the azole-resistant strain.
Mondello, Francesca; Girolamo, Antonietta; Scaturro, Maria; Ricci, Maria Luisa
The aim of this study was to determine the in vitro activity of Melaleuca alternifolia Cheel (tea tree) oil (TTO) against 22 strains of Legionella pneumophila of different serogroup and source of isolation. Both a standard broth micro-dilution method, with slight modifications, and a micro-atmosphere diffusion method were used. Furthermore, we have established a simple sealing procedure in the micro-dilution method to determine the antibacterial activity of TTO against Legionella in aqueous phase. The results showed that L. pneumophila, quite irrespective of serogroup and source of isolation, is exquisitely sensitive to TTO, with minimal inhibitory concentration (MIC) ranging from 0.125 to 0.5% v/v, and a bactericidal activity at 0.5% v/v. In addition, we show here that TTO vapours exert critical activity, that must be controlled for reproducible MIC determinations. Overall, our data suggest that TTO could be active as anti-Legionella disinfectant, for control of water system contamination, especially in spas, in small waterlines or in particular respiratory medical devices.
Greay, S J; Ireland, D J; Kissick, H T; Levy, A; Beilharz, M W; Riley, T V; Carson, C F
To examine the in vitro anticancer activity of Melaleuca alternifolia (tea tree) oil (TTO), and its major active terpene component, terpinen-4-ol, against two aggressive murine tumour cell lines, AE17 mesothelioma and B16 melanoma. Effects of TTO and terpinen-4-ol on the cellular viability of two tumour cell lines and fibroblast cells were assessed by MTT assay. Induction of apoptotic and necrotic cell death was visualised by fluorescent microscopy and quantified by flow cytometry. Tumour cell ultrastructural changes were examined by transmission electron microscopy and changes in cell cycle distribution were assessed by flow cytometry, with changes in cellular morphology monitored by video time lapse microscopy. TTO and terpinen-4-ol significantly inhibited the growth of two murine tumour cell lines in a dose- and time-dependent manner. Interestingly, cytotoxic doses of TTO and terpinen-4-ol were significantly less efficacious against non-tumour fibroblast cells. TTO and terpinen-4-ol induced necrotic cell death coupled with low level apoptotic cell death in both tumour cell lines. This primary necrosis was clarified by video time lapse microscopy and also by transmission electron microscopy which revealed ultrastructural features including cell and organelle swelling following treatment with TTO. In addition, both TTO and terpinen-4-ol induced their inhibitory effect by eliciting G1 cell cycle arrest. TTO and terpinen-4-ol had significant anti-proliferative activity against two tumour cell lines. Moreover, the identification of primary necrotic cell death and cell cycle arrest of the aggressive tumour cells highlights the potential anticancer activity of TTO and terpinen-4-ol.
Mondello, Francesca; De Bernardis, Flavia; Girolamo, Antonietta; Cassone, Antonio; Salvatore, Giuseppe
Background Recent investigations on the antifungal properties of essential oil of Melaleuca alternifolia Cheel (Tea Tree Oil, TTO) have been performed with reference to the treatment of vaginal candidiasis. However, there is a lack of in vivo data supporting in vitro results, especially regarding the antifungal properties of TTO constituents. Thus, the aim of our study was to investigate the in vitro and the in vivo anti-Candida activity of two critical bioactive constituents of TTO, terpinen-4-ol and 1,8-cineole. Methods Oophorectomized, pseudoestrus rats under estrogen treatment were used for experimental vaginal infection with azole (fluconazole, itraconazole) -susceptible or -resistant strains of C. albicans. All these strains were preliminarily tested for in vitro susceptibility to TTO, terpinen-4-ol and 1,8-cineole for their antifungal properties, using a modification of the CLSI (formerly NCCLS) reference M27-A2 broth micro-dilution method. Results In vitro minimal inhibitory concentrations (MIC90) values were 0.06% (volume/volume) for terpinen-4-ol and 4% (volume/volume) for 1,8-cineole, regardless of susceptibility or resistance of the strains to fluconazole and itraconazole. Fungicidal concentrations of terpinen-4-ol were equivalent to the candidastatic activity. In the rat vaginal infection model, terpinen-4-ol was as active as TTO in accelerating clearance from the vagina of all Candida strains examined. Conclusion Our data suggest that terpinen-4-ol is a likely mediator of the in vitro and in vivo activity of TTO. This is the first in vivo demonstration that terpinen-4-ol could control C. albicans vaginal infections. The purified compound holds promise for the treatment of vaginal candidiasis, and particularly the azole-resistant forms. PMID:17083732
Mertas, Anna; Garbusińska, Aleksandra; Szliszka, Ewelina; Jureczko, Andrzej; Kowalska, Magdalena; Król, Wojciech
The aim of this study was to evaluate the activity of fluconazole against 32 clinical strains of fluconazole-resistant Candida albicans, and C. albicans ATCC 10231 reference strain, after their exposure to sublethal concentrations of tea tree oil (TTO) or its main bioactive component terpinen-4-ol. For all tested fluconazole-resistant C. albicans strains TTO and terpinen-4-ol minimal inhibitory concentrations (MICs) were low, ranging from 0.06% to 0.5%. The 24-hour exposure of fluconazole-resistant C. albicans strains to fluconazole with sublethal dose of TTO enhanced fluconazole activity against these strains. Overall, 62.5% of isolates were classified as susceptible, 25.0% exhibited intermediate susceptibility, and 12.5% were resistant. For all of the tested clinical strains the fluconazole MIC decreased from an average of 244.0 μg/mL to an average of 38.46 μg/mL, and the fluconazole minimal fungicidal concentrations (MFC) decreased from an average of 254.67 μg/mL to an average of 66.62 μg/mL. Terpinen-4-ol was found to be more active than TTO, and strongly enhanced fluconazole activity against fluconazole-resistant C. albicans strains. The results of this study demonstrate that combining natural substances such as TTO and conventional drug such as fluconazole, may help treat difficult yeast infections.
Banes-Marshall, L; Cawley, P; Phillips, C A
This study investigates the in vitro activity of tea tree oil (TTO) against a range of wild strains of microorganisms isolated from clinical specimens of leg ulcers and pressure sores. The antimicrobial effectiveness of TTO is determined in terms of minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) or minimum fungicidal concentration (MFC). The isolates include methicillin-resistant Staphylococcus aureus (MRSA), S. aureus, faecal streptococci, beta-haemolytic streptococci, coagulase-negative staphylococci, Pseudomonas spp. and coliform bacilli. Eleven Candida spp. isolates from skin and vaginal swabs also are tested. Using an agar dilution assay, the MICs of TTO in 88 out of 90 isolates was 0.5-1.0% (v/v), whilst with P. aeruginosa it was >2% (v/v). A broth microdilution method was used to determine MIC and minimum cidal concentration (MCC) of 80 isolates. In 64 isolates, TTO produced an inhibitory and cidal effect at 3% and 4% (v/v), respectively. S. aureus and Candida spp. were the most susceptible to TTO, with MICs and MBCs of 0.5% and 1%, respectively. P. aeruginosa and the faecal streptococci isolates, with MICs and MBCs of >8%, were resistant to TTO.
D'Arrigo, Manuela; Ginestra, Giovanna; Mandalari, Giuseppina; Furneri, P M; Bisignano, G
The application of antimicrobial combinations may address the rising resistance to established classes of both systemic and topical agents and their clinical relevance is related to the presence of a significant postantibiotic effect (PAE). We investigated the effectiveness in vitro of the association between tobramycin and tea tree oil (TTO) against Gram-positive and Gram-negative bacteria. The minimal inhibitory concentrations, the bacterial killing and the PAE of tobramycin and TTO were determined both singly and in combination against Escherichia coli ATCC 25922 and Staphylococcus aureus ATCC 29213. A synergistic interaction was observed against both strains tested: the mean PAEs were 1.3 and 1.7h for tobramycin against E. coli and S. aureus respectively, 10.8h for tobramycin and TTO (0.05%) against E. coli, 10.4h and 17.4h against S. aureus for tobramycin and TTO (0.25 and 0.50%, respectively). Longer PASMEs were observed with S. aureus after TTO/tobramycin exposure. In vitro interactions can improve the antimicrobial effectiveness of the antibiotic and may contribute for the development of novel topical agents for the treatment of skin lesions including conjunctiva and respiratory infections by inhalation.
Lim, Ee Lin; Hammer, Katherine Ann
This study investigated the hypothesis that the salt adaptation response of Enterococcus faecalis alters susceptibility to tea tree oil (TTO). Six E. faecalis isolates were adapted to 6.5 % NaCl, and then exposed to TTO in phosphate-buffered saline (PBS). One isolate was also exposed to TTO in Brain Heart Infusion Broth (BHIB). The viability of salt-adapted and non-adapted control cells was determined at 0, 45 and 90 min and compared. MICs for several antibiotics and TTO were also determined by E test and broth microdilution, respectively. Results showed that susceptibility to TTO in PBS was significantly reduced after salt adaptation for five isolates (83 %) (P < 0.05). Mean differences between salt-adapted and non-adapted cell counts were 2.51 log at 45 min and 2.13 log at 90 min. However, when E. faecalis ATCC 19433 was exposed to TTO in BHIB, no significant differences were seen. In conclusion, salt adaptation resulted in reduced susceptibility to TTO in PBS for the majority of isolates, indicating that cross protection had occurred. This effect was absent in BHIB, suggesting that the uptake of compatible solutes from the growth medium protected non-adapted cells from TTO. Whether this has implications for the clinical effectiveness of TTO remains to be determined.
Garbusińska, Aleksandra; Kowalska, Magdalena; Król, Wojciech
The aim of this study was to evaluate the activity of fluconazole against 32 clinical strains of fluconazole-resistant Candida albicans, and C. albicans ATCC 10231 reference strain, after their exposure to sublethal concentrations of tea tree oil (TTO) or its main bioactive component terpinen-4-ol. For all tested fluconazole-resistant C. albicans strains TTO and terpinen-4-ol minimal inhibitory concentrations (MICs) were low, ranging from 0.06% to 0.5%. The 24-hour exposure of fluconazole-resistant C. albicans strains to fluconazole with sublethal dose of TTO enhanced fluconazole activity against these strains. Overall, 62.5% of isolates were classified as susceptible, 25.0% exhibited intermediate susceptibility, and 12.5% were resistant. For all of the tested clinical strains the fluconazole MIC decreased from an average of 244.0 μg/mL to an average of 38.46 μg/mL, and the fluconazole minimal fungicidal concentrations (MFC) decreased from an average of 254.67 μg/mL to an average of 66.62 μg/mL. Terpinen-4-ol was found to be more active than TTO, and strongly enhanced fluconazole activity against fluconazole-resistant C. albicans strains. The results of this study demonstrate that combining natural substances such as TTO and conventional drug such as fluconazole, may help treat difficult yeast infections. PMID:25722982
Homeyer, Diane C; Sanchez, Carlos J; Mende, Katrin; Beckius, Miriam L; Murray, Clinton K; Wenke, Joseph C; Akers, Kevin S
Invasive fungal wound infections (IFIs) are increasingly reported in trauma patients and cause considerable morbidity and mortality despite standard of care treatment in trauma centers by experienced medical personnel. Topical agents such as oil of melaleuca, also known as tea tree oil (TTO), have been proposed for adjunctive treatment of IFIs. We evaluated the activity of TTO against filamentous fungi associated with IFIs by testing 13 clinical isolates representing nine species via time-kill assay with seven concentrations of TTO (100%, 75%, 50%, 25%, 10%, 5%, and 1%). To ascertain the safety of topical application to wounds, cell viability assays were performed in vitro using human fibroblasts, keratinocytes, osteoblasts, and umbilical vein endothelial cells with 10 concentrations of TTO (75%, 50%, 25%, 10%, 5%, and 10-fold serial dilutions from 1 to 0.0001%) at five time points (5, 15, 30, 60, and 180 min). Compatibility of TTO with explanted porcine tissues was also assessed with eight concentrations of TTO (100%, 75%, 50%, 25%, 10%, 5%, 1%, and 0.1%) at the time points used for cellular assays and at 24 h. The time-kill studies showed that fungicidal activity was variable between isolates. The effect of TTO on cell viability was primarily concentration dependent with significant cytotoxicity at concentrations of ≥ 10% and ≥ 50% for cells lines and whole tissue, respectively. Our findings demonstrate that TTO possesses antifungal activity against filamentous fungi associated with IFIs; furthermore that negligible effects on whole tissues, in contrast to individual cells, were observed following exposure to TTO. Collectively, these findings indicate a potential use of TTO as topical treatment of IFIs.
Uncontrolled, open-label, pilot study of tea tree (Melaleuca alternifolia) oil solution in the decolonisation of methicillin-resistant Staphylococcus aureus positive wounds and its influence on wound healing.
Edmondson, Margaret; Newall, Nelly; Carville, Keryln; Smith, Joanna; Riley, Thomas V; Carson, Christine F
Many complementary and alternative products are used to treat wounds. The essential oil of Melaleuca alternifolia, tea tree oil, has proven antimicrobial and anti-inflammatory properties, may be useful in methicillin-resistant Staphylococcus aureus (MRSA) decolonisation regimens and is reputed to have 'wound-healing' properties, but more data are required to support these indications. The primary aim of this uncontrolled case series was to assess whether a tea tree oil solution used in a wound cleansing procedure could decolonise MRSA from acute and chronic wounds of mixed aetiology. The secondary aim was to determine if the tea tree oil solution influenced wound healing outcomes. Nineteen participants with wounds suspected of being colonised with MRSA were enrolled in a pilot study. Seven were subsequently shown not to have MRSA and were withdrawn from the study. As many as 11 of the remaining 12 participants were treated with a water-miscible tea tree oil (3·3%) solution applied as part of the wound cleansing regimen at each dressing change. Dressing changes were three times per week or daily as deemed necessary by the study nurse following assessment. One participant withdrew from the study before treatment. No participants were MRSA negative after treatment. After treatment had been implemented, 8 of the 11 treated wounds had begun to heal and reduced in size as measured by computer planimetry. Although this formulation and mode of delivery did not achieve the primary aim of the study, tea tree oil did not appear to inhibit healing and the majority of wounds reduced in size after treatment.
Mann, C M; Cox, S D; Markham, J L
Pseudomonas aeruginosa is less susceptible to the antimicrobial properties of tea tree oil than many bacteria and its tolerance is considered to be due to its outer membrane. Polymyxin B nonapeptide (PMBN), which has no antibacterial action, was used to permeabilize the outer membrane. The addition of PMBN to Ps. aeruginosa NCTC 6749 markedly increased this organism's susceptibility to tea tree oil and to its normally inert hydrocarbons, p-cymene and gamma-terpinene.
van der Valk, P G; de Groot, A C; Bruynzeel, D P; Coenraads, P J; Weijland, J W
In four patients, three women aged 45, 29 and 52 years and a man aged 45 years, allergic contact dermatitis due to 'tea tree' oil was diagnosed. The case of the man was published before. 'Tea tree' oils are essential oils distilled from the leaves of myrtaceous trees and shrubs occurring in Australia and South-East Asia. The 'tea tree' oil available in the Netherlands is distilled from the Melaleuca alternifolia and mainly contains eucalyptol. Eucalyptol is probably the most important allergen.
Carson, Christine F; Smith, David W; Lampacher, Gail J; Riley, Thomas V
Double-blinding is an important and widely implemented feature of clinical trials although its success is rarely assessed. In a randomized, placebo-controlled trial of tea tree oil, an aromatic essential oil, for the treatment of recurrent herpes labialis (RHL), or cold sores, deception was used to prevent volunteers from identifying their treatment allocation. Volunteers received placebo (n=102) or tea tree oil (n=112) ointment in preparation for their next episode of RHL and were told, falsely, that the aroma of the ointments had been changed to prevent identification of the treatment group. At the trial's end, of the volunteers who had used their ointment and presented for treatment assessment (n=100), approximately 50% correctly guessed their treatment allocation (P=0.774). Amongst volunteers that had not presented for treatment assessment (n=114), 12 volunteers did not provide blinding data and 46 did not open their tube. For the 56 volunteers who opened their tube, less than half of those receiving tea tree oil (44.4%) and only a small proportion of those on placebo (17.2%) were able to correctly identify their treatment allocation. Among the volunteers that were not treated, the P-value was 0.083. This study showed that the ethical use of deception may provide effective blinding in challenging circumstances.
Detection and identification of 1-methylethyl and methyl radicals generated by irradiating tea tree (Melaleuca alternifolia) oil with visible light (436 nm) in the presence of flavin mononucleotide and ferrous ion.
Mori, H-M; Iwahashi, H
Here, we determined the electron spin resonance (ESR) spectra of standard reaction mixtures (I) containing 25 μM flavin mononucleotide (FMN), 0.018% tea tree (Melaleuca alternifolia) oil, 1.9 M acetonitrile, 20 mM phosphate buffer (pH 7.4), 0.1 M α-(4-pyridyl-1-oxide)-N-tert-butylnitrone (4-POBN), and 1.0 mM FeSO₄(NH₄)₂SO₄ irradiated with 436 nm visible light (7.8 J/cm²). Prominent ESR signals (αN = 1.58 mT and αHβ = 0.26 mT) were detected, suggesting that free radicals form in the standard reaction. In order to know whether singlet oxygen (¹O₂) is involved in the radical formation or not, ESR measurement was performed for the standard D₂O reaction mixture (I) which contained 25 μM FMN, 0.0036% tea tree oil, 1.9 M acetonitrile-d3, 20 mM phosphate buffer (pH 7.4), 0.1 M 4-POBN and 1.0 mM FeSO₄ in D₂O. The ESR peak height of the standard D₂O reaction increased to 169 ± 24% of the control. Thus, ¹O₂ seems to be involved in the formation of the radicals because D₂O increases the lifetime of singlet oxygen. High-performance liquid chromatography-ESR-mass spectrometry analyses detected 1-methylethyl and methyl radicals in the standard reaction. The radicals appear to form through the reaction of ferrous ion with α-terpinene endoperoxide (ascaridole), which generated from the reaction of α-terpinene with ¹O₂. The 1-methylethyl and methyl radicals may exert a pro-oxidant effect under these conditions.
Russell, Michael F; Southwell, Ian
An analytical method for determining the quality and hence the chemical variety status of tea tree transplants is described. The key to the procedure was found to be the leaf age of the test material. Investigation at very early development stages was seen to give misleading results due to the sequential onset of different monoterpenoid biogenetic pathways. For example, in the first few leaves, the high concentration of terpinolene in the terpinen-4-ol variety suggests that the terpinolene variety is under investigation. However, 1,8-cineole percent concentrations in plantation tree leaf were approximately 1.6 times lower than those measured for seedlings prior to transplant. Consequently, the use of a plantation cineole indicator is proposed for estimating plantation cineole from seedling leaf analyses. Although recent investigations enable the chemotype status to be predicted with some certainty, it is now proposed that analysis of leaf set 10 at the age of 6 weeks (seedling age approximately 17 weeks) provides an unambiguous analysis and correlates seedling quality with mature plantation quality. In addition, the oil yield of mature tea tree leaf was found, by steam distillation, to be approximately 5 times higher than that of seedling leaf.
Hartford, Orville; Zug, Kathryn A
Tea tree oil is a popular ingredient in many over-the-counter healthcare and cosmetic products. With the explosion of the natural and alternative medicine industry, more and more people are using products containing tea tree oil. This article reviews basic information about tea tree oil and contact allergy, including sources of tea tree oil, chemical composition, potential cross reactions, reported cases of allergic contact dermatitis, allergenic compounds in tea tree oil, practical patch testing information, and preventive measures.
Elgendy, Enas Ahmed; Ali, Shereen Abdel-Moula; Zineldeen, Doaa Hussien
Conventional non-surgical periodontal therapy has been proven to be an effective treatment for patients with chronic periodontitis. Tea tree oil (TTO) can be used as adjunct to conventional periodontal therapy in patient with chronic periodontitis. The aim of this study was to evaluate the effectiveness of adjunctive treatment of TTO on the clinical parameters and the level of pentraxin-3 (PTX3) in chronic periodontitis. A total of 40 patients with moderate to severe chronic periodontitis were divided into two groups, Group I received scaling and root planing (SRP) only, Group II received SRP and TTO gel. Clinical parameters were recorded and gingival crevicular fluid (GCF) samples were collected from each subject for measuring PTX3 levels at baseline, 1, 3 and 6 months after treatment. In all evaluation periods, there was statistically significant reduction in each of the studied clinical parameters and PTX3 level in Group II as compared with Group I. The local delivery of TTO gel in case of chronic periodontitis may have some beneficial effects to augment the results of the conventional periodontal therapy. Moreover, it places a focus on the value of monitoring GCF levels of PTX3 as a marker of periodontal tissue healing.
Elgendy, Enas Ahmed; Ali, Shereen Abdel-Moula; Zineldeen, Doaa Hussien
Background: Conventional non-surgical periodontal therapy has been proven to be an effective treatment for patients with chronic periodontitis. Tea tree oil (TTO) can be used as adjunct to conventional periodontal therapy in patient with chronic periodontitis. The aim of this study was to evaluate the effectiveness of adjunctive treatment of TTO on the clinical parameters and the level of pentraxin-3 (PTX3) in chronic periodontitis. Materials and Methods: A total of 40 patients with moderate to severe chronic periodontitis were divided into two groups, Group I received scaling and root planing (SRP) only, Group II received SRP and TTO gel. Clinical parameters were recorded and gingival crevicular fluid (GCF) samples were collected from each subject for measuring PTX3 levels at baseline, 1, 3 and 6 months after treatment. Results: In all evaluation periods, there was statistically significant reduction in each of the studied clinical parameters and PTX3 level in Group II as compared with Group I. Conclusions: The local delivery of TTO gel in case of chronic periodontitis may have some beneficial effects to augment the results of the conventional periodontal therapy. Moreover, it places a focus on the value of monitoring GCF levels of PTX3 as a marker of periodontal tissue healing. PMID:24174722
Yim, Wei Tsun; Bhandari, Bhesh; Jackson, Louise; James, Peter
Rhipicephalus australis (formerly Boophilus microplus) is a one host tick responsible for major economic loss in tropical and subtropical cattle production enterprises. Control is largely dependent on the application of acaricides but resistance has developed to most currently registered chemical groups. Repellent compounds that prevent initial attachment of tick larvae offer a potential alternative to control with chemical toxicants. The repellent effects of Melaleuca alternifolia oil (TTO) emulsions and two β-cyclodextrin complex formulations, a slow release form (SR) and a modified faster release form (FR), were examined in a series of laboratory studies. Emulsions containing 4% and 5% TTO applied to cattle hair in laboratory studies completely repelled ascending tick larvae for 24h whereas 2% and 3% formulations provided 80% protection. At 48h, 5% TTO provided 78% repellency but lower concentrations repelled less than 60% of larvae. In a study conducted over 15 days, 3% TTO emulsion applied to cattle hair provided close to 100% repellency for 2 days, but then protection fell to 23% by day 15. The FR formulation gave significantly greater repellency than the emulsion and the SR formulation from day 3 until the end of the study (P<0.05), providing almost complete repellency at day 3 (99.5%), then decreasing over the period of the study to 49% repellency at day 15. Proof of concept is established for the use of appropriately designed controlled-release formulations to extend the period of repellency provided by TTO against R. australis larvae.
Bozzuto, Giuseppina; Colone, Marisa; Toccacieli, Laura; Stringaro, Annarita; Molinari, Agnese
In this study we present new data from experiments focused on the antitumor activity of tea tree oil (TTO), an essential oil distilled from Melaleuca alternifolia. TTO proved to be capable of inhibiting the growth of melanoma cells and of overcoming multidrug resistance (MDR), as we reported in our previous study. Moreover, the survival role of the MDR-marker P-glycoprotein appears to be involved in the mechanism of invasion of melanoma cells. The results reported herein indicate that TTO and its main active component, terpinen-4-ol, can also interfere with the migration and invasion processes of drug-sensitive and drug-resistant melanoma cells.
Larson, David; Jacob, Sharon E
Tea tree oil is an increasingly popular ingredient in a variety of household and cosmetic products, including shampoos, massage oils, skin and nail creams, and laundry detergents. Known for its potential antiseptic properties, it has been shown to be active against a variety of bacteria, fungi, viruses, and mites. The oil is extracted from the leaves of the tea tree via steam distillation. This essential oil possesses a sharp camphoraceous odor followed by a menthol-like cooling sensation. Most commonly an ingredient in topical products, it is used at a concentration of 5% to 10%. Even at this concentration, it has been reported to induce contact sensitization and allergic contact dermatitis reactions. In 1999, tea tree oil was added to the North American Contact Dermatitis Group screening panel. The latest prevalence rates suggest that 1.4% of patients referred for patch testing had a positive reaction to tea tree oil.
Tong, M M; Altman, P M; Barnetson, R S
Tea tree oil (an essential oil derived primarily from the Australian native Melaleuca alternifolia) has been used as a topical antiseptic agent since the early part of this century for a wide variety of skin infections; however, to date, the evidence for its efficacy in fungal infections is still largely anecdotal. One hundred and four patients completed a randomized, double-blind trial to evaluate the efficacy of 10% w/w tea tree oil cream compared with 1% tolnaftate and placebo creams in the treatment of tinea pedis. Significantly more tolnaftate-treated patients (85%) than tea tree oil (30%) and placebo-treated patients (21%) showed conversion to negative culture at the end of therapy (p < 0.001); there was no statistically significant difference between tea tree oil and placebo groups. All three groups demonstrated improvement in clinical condition based on the four clinical parameters of scaling, inflammation, itching and burning. The tea tree oil group (24/37) and the tolnaftate group (19/33) showed significant improvement in clinical condition when compared to the placebo group (14/34; p = 0.022 and p = 0.018 respectively). Tea tree oil cream (10% w/w) appears to reduce the symptomatology of tinea pedis as effectively as tolnaftate 1% but is no more effective than placebo in achieving a mycological cure. This may be the basis for the popular use of tea tree oil in the treatment of tinea pedis.
Tea tree oil (TTO) is a popular skin remedy obtained from the leaves of Melaleuca alternifolia, M. linariifolia or M dissitiflora. Due to the commercial importance ofTTO, substitution or adulteration with other tea tree species (such as cajeput, niaouli, manuka and kanuka oils) is common and may p...
Pazyar, Nader; Yaghoobi, Reza
Psoriasis is a clinical skin disease that is characterized by erythematous scaling plaques and involves the extensor site of the extremities, the scalp and other surfaces of the skin. Tea tree oil (TTO) is considered an essential oil, obtained by steam distillation of the leaves and terminal branchlets of Melaleuca alternifolia. Notably,terpinen-4-ol, the major TTO constituent, has been found to have potent anti-inflammatory properties. It is suggested that terpinen-4-ol may be a novel potential agent against psoriasis. This article draws attention to the antipsoriatic effect of TTO and provides a theoretical molecular approach. Copyright © 2012 S. Karger AG, Basel.
Pazyar, Nader; Yaghoobi, Reza; Bagherani, Nooshin; Kazerouni, Afshin
Tea tree oil (TTO) is an essential oil, steam-distilled from the Australian native plant, Melaleuca alternifolia. It has a minimum content of terpinen-4-ol and a maximum content of 1, 8-cineole. Terpinen-4-ol is a major TTO component which exhibits strong antimicrobial and anti-inflammatory properties. Tea tree oil exerts antioxidant activity and has been reported to have broad-spectrum antimicrobial activity against bacterial, viral, fungal, and protozoal infections affecting skin and mucosa. Several studies have suggested the uses of TTO for the treatment of acne vulgaris, seborrheic dermatitis, and chronic gingivitis. It also accelerates the wound healing process and exhibits anti-skin cancer activity. This review opens up new horizons for dermatologists in the use of this herbal agent.
Groppo, F C; Ramacciato, J C; Simões, R P; Flório, F M; Sartoratto, A
To compare the antimicrobial activity of tea tree oil, garlic, and chlorhexidine solutions against oral microorganisms. The five-week study consisted of thirty subjects. The first week was considered baseline. All subjects used a control solution (second week), and were randomly divided into the three groups (third week): G1-0.12% chlorhexidine; G2 - 2.5% garlic (Allium sativum, L.); and G3 - 0.2% tea tree oil (Melaleuca alternifolia). Dishes containing blood agar and Mitis Salivarius Bacitracin agar (MSB) were inoculated with the subjects' saliva (collected twice a week). Total microorganisms and mutans streptococci were counted in blood agar and MSB, respectively. Chlorhexidine and garlic groups showed antimicrobial activity against mutans streptococci, but not against other oral microorganisms. The tea tree oil group showed antimicrobial activity against mutans streptococci and other oral microorganisms. Maintenance of reduced levels of microorganisms was observed only for garlic and tea tree oil during the two consecutive weeks (fourth and fifth). Unpleasant taste (chlorhexidine 40%, tea tree oil 30%, garlic 100%), burning sensation (chlorhexidine 40%, tea tree oil 60%, garlic 100%), bad breath (chlorhexidine 40%, tea tree oil 20%, garlic 90%), and nausea (chlorhexidine 0%, tea tree oil 10%, garlic 30%) were reported. Garlic and tea tree oil might be an alternative to chlorhexidine.
96262 ... https://nccih.nih.gov/health/tea/treeoil.htm ... us ... 96262 ... https://nccih.nih.gov/health/tea/treeoil.htm ... Herbal Medicine ... Herbal Medicine/Specifics ... us ... 96262 ... https:// ...
Khanna, M; Qasem, K; Sasseville, D
The commercial production of tea tree oil, extracted from Melaleuca alternifolia Cheel, has considerably increased over the past 15 years in response to a strong demand for natural remedies and aromatic substances. The number of case reports that describe allergic contact dermatitis (ACD) to this essential oil is also on the rise. We report an additional case of ACD to tea tree oil that presented with an extensive erythema multiforme-like reaction. A skin biopsy was performed from a targetlike lesion distant from the site of the initial dermatitis. The patient was treated with systemic and topical corticosteroids. Five months later, he was patch tested to the North American standard series, to his own tea tree oil, to a fresh batch of tea tree oil, and to some related allergens. The skin biopsy showed a spongiotic dermatitis without histological features of erythema multiforme. Patch testing elicited a 3+ reaction to old, oxidized tea tree oil, a 2+ reaction to fresh tea tree oil, a 2+ reaction to colophony, a 1+ reaction to abitol, and a 1+ reaction to balsam of Peru. We believe this is the first report of erythema multiforme-like reaction secondary to ACD from tea tree oil. Other interesting features are the stronger reaction to oxidized than to fresh tea tree oil, and concomitant reactivity to colophony, abitol, and balsam of Peru.
Minghetti, Paola; Casiraghi, Antonella; Cilurzo, Francesco; Gambaro, Veniero; Montanari, Luisa
The antimicrobial, antifungal and anti-inflammatory properties of tea tree oil (TTO), the essential oil of Melaleuca alternifolia are well documented. In order to optimize its therapeutic activity, TTO patches were designed. The aim of this work was the formulation of monolayer patches containing TTO. Moreover, the performance of oleic acid (OA) as a skin penetration enhancer in patches was evaluated. Terpinen-4-ol (T4OL), the main component of TTO, was the marker used to evaluate TTO skin permeability. The permeation study was performed through human epidermis by using Franz diffusion cells. Patches were prepared by using methacrylic copolymers, Eudragit E100 (EuE100) or Eudragit NE (EuNE), and a silicone resin, BioPSA7-4602 (Bio-PSA). TTO and OA contents were fixed at 10% w/w and 3% w/w, respectively. The patches were prepared by a casting method and characterised in terms of T4OL content and skin permeability. All the selected polymers were suitable as the main component of the patch matrix. Since the main critical issue in the use of TTO is related to its toxicity after absorption, the local administration of TTO can take advantage of the use of patches based on EuE100 because of the high retained amount and the low permeation of T4OL. In this matrix, OA slightly increased the T4OL retained amount, improving the efficacy and safety of TTO patches.
Halcón, Linda; Milkus, Kelly
Antibiotic-resistant bacteria continue to be a major health concern worldwide. In particular, Staphylococcus aureus, both methicillin-resistant and -sensitive, are of concern in their ability to cause difficult skin and underlying tissue infections. Melaleuca alternifolia oil (tea tree oil), an essential oil, has demonstrated promising efficacy in treating these infections. Tea tree oil has been used for centuries as a botanical medicine, and has only in recent decades surfaced in the scientific literature as a promising adjunctive wound treatment. Tea tree oil is antimicrobial, anti-inflammatory, and has demonstrated ability to activate monocytes. There are few apparent side effects to using tea tree oil topically in low concentrations, with contact dermatitis being the most common. Tea tree oil has been effective as an adjunctive therapy in treating osteomyelitis and infected chronic wounds in case studies and small clinical trials. There is a need for larger clinical trials to further examine efficacy of tea tree oil as an adjunctive wound therapy, as well as improved guidelines for developing plant-based medicines.
Hammer, K A
Over-the-counter acne treatments containing tea tree oil from the plant Melaleuca alternifolia are widely available, and evidence indicates that they are a common choice amongst those self-treating their acne. The aims of this review were to collate and evaluate the clinical evidence on the use of tea tree oil products for treating acne, to review safety and tolerability and to discuss the underlying modes of therapeutic action. Copyright © 2014 Elsevier B.V. and the International Society of Chemotherapy. All rights reserved.
Bassett, I B; Pannowitz, D L; Barnetson, R S
Tea-tree oil (an essential oil of the Australian native tree Melaleuca alternifolia) has long been regarded as a useful topical antiseptic agent in Australia and has been shown to have a variety of antimicrobial activities; however, only anecdotal evidence exists for its efficacy in the treatment of various skin conditions. We have performed a single-blind, randomised clinical trial on 124 patients to evaluate the efficacy and skin tolerance of 5% tea-tree oil gel in the treatment of mild to moderate acne when compared with 5% benzoyl peroxide lotion. The results of this study showed that both 5% tea-tree oil and 5% benzoyl peroxide had a significant effect in ameliorating the patients' acne by reducing the number of inflamed and non-inflamed lesions (open and closed comedones), although the onset of action in the case of tea-tree oil was slower. Encouragingly, fewer side effects were experienced by patients treated with tea-tree oil.
Flores, F C; de Lima, J A; Ribeiro, R F; Alves, S H; Rolim, C M B; Beck, R C R; da Silva, Cristiane Bona
The aim of this study was to evaluate, for the first time, the antifungal efficacy of nanocapsules and nanoemulsions containing Melaleuca alternifolia essential oil (tea tree oil) in an onychomycosis model. The antifungal activity of nanostructured formulations was evaluated against Trichophyton rubrum in two different in vitro models of dermatophyte nail infection. First, nail powder was infected with T. rubrum in a 96-well plate and then treated with the formulations. After 7 and 14 days, cell viability was verified. The plate counts for the samples were 2.37, 1.45 and 1.0 log CFU mL(-1) (emulsion, nanoemulsion containing tea tree oil and nanocapsules containing tea tree oil, respectively). A second model employed nails fragments which were infected with the microorganism and treated with the formulations. The diameter of fungal colony was measured. The areas obtained were 2.88 ± 2.08 mm(2), 14.59 ± 2.01 mm(2), 40.98 ± 2.76 mm(2) and 38.72 ± 1.22 mm(2) for the nanocapsules containing tea tree oil, nanoemulsion containing tea tree oil, emulsion and untreated nail, respectively. Nail infection models demonstrated the ability of the formulations to reduce T. rubrum growth, with the inclusion of oil in nanocapsules being most efficient.
Giordani, Cristiano; Molinari, Agnese; Toccacieli, Laura; Calcabrini, Annarica; Stringaro, Annarita; Chistolini, Pietro; Arancia, Giuseppe; Diociaiuti, Marco
Tea tree oil (TTO) is the essential oil steam-distilled from Melaleuca alternifolia, a species of northern New South Wales, Australia. It exhibits a broad-spectrum antimicrobial activity and an antifungal activity. Only recently has TTO been shown to inhibit the in vitro growth of multidrug resistant (MDR) human melanoma cells. It has been suggested that the effect of TTO on tumor cells could be mediated by its interaction with the plasma membrane, most likely by inducing a reorganization of lipid architecture. In this paper we report biophysical and structural results obtained using simplified planar model membranes (Langmuir films) mimicking lipid "rafts". We also used flow cytometry analysis (FCA) and freeze-fracturing transmission electron microscopy to investigate the effects of TTO on actual MDR melanoma cell membranes. Thermodynamic (compression isotherms and adsorption kinetics) and structural (Brewster angle microscopy) investigation of the lipid monolayers clearly indicates that TTO interacts preferentially with the less ordered DPPC "sea" and that it does not alter the more ordered lipid "rafts". Structural observations, performed by freeze fracturing, confirm that TTO interacts with the MDR melanoma cell plasma membrane. Moreover, experiments performed by FCA demonstrate that TTO does not interfere with the function of the MDR drug transporter P-gp. We therefore propose that the effect exerted on MDR melanoma cells is mediated by the interaction with the fluid DPPC phase, rather than with the more organized "rafts" and that this interaction preferentially influences the ATP-independent antiapoptotic activity of P-gp likely localized outside "rafts".
Cuaron, Jesus A; Dulal, Santosh; Song, Yang; Singh, Atul K; Montelongo, Cesar E; Yu, Wanqin; Nagarajan, Vijayaraj; Jayaswal, Radheshyam K; Wilkinson, Brian J; Gustafson, John E
Tea tree oil (TTO) is a steam distillate of Melaleuca alternifolia that demonstrates broad-spectrum antibacterial activity. This study was designed to document how TTO challenge influences the Staphylococcus aureus transcriptome. Overall, bioinformatic analyses (S. aureus microarray meta-database) revealed that both ethanol and TTO induce related transcriptional alterations. TTO challenge led to the down-regulation of genes involved with energy-intensive transcription and translation, and altered the regulation of genes involved with heat shock (e.g. clpC, clpL, ctsR, dnaK, groES, groEL, grpE and hrcA) and cell wall metabolism (e.g. cwrA, isaA, sle1, vraSR and vraX). Inactivation of the heat shock gene dnaK or vraSR which encodes a two-component regulatory system that responds to peptidoglycan biosynthesis inhibition led to an increase in TTO susceptibility which demonstrates a protective role for these genes in the S. aureus TTO response. A gene (mmpL) encoding a putative resistance, nodulation and cell division efflux pump was also highly induced by TTO. The principal antimicrobial TTO terpene, terpinen-4-ol, altered ten genes in a transcriptional direction analogous to TTO. Collectively, this study provides additional insight into the response of a bacterial pathogen to the antimicrobial terpene mixture TTO.
Baker, G R; Lowe, R F; Southwell, I A
Two methods for the determination of oil and oil major components from tea tree (Melaleuca alternifolia) leaf are quantitatively compared. A microwave assisted ethanol extraction and a 2-h hydrodistillation technique were used on both dry and fresh leaf from a low and a high oil concentration tree. There was no significant difference between dry and fresh leaf. The distillation technique recovered 88% and 82% of the extractable oil for the low and high concentration material, respectively. For both samples this distilled oil was composed of lower absolute amounts of sesquiterpenoids and marginally lower amounts of monoterpenoids. Extending the distillation to 6 h increased the sesquiterpenoid recovery but this resulted in a reduction in both the absolute and relative amounts of the oxygenated monoterpenoids, terpinen-4-ol and 1,8-cineole.
Mills, Clive; Cleary, Brian J; Gilmer, John F; Walsh, John J
Pediculosis is a widespread condition reported in schoolchildren. Treatment most commonly involves the physical removal of nits using fine-toothcombs and the chemical treatment of adult lice and eggs with topical preparations. The active constituents of these preparations frequently exert their effects through inhibition of acetylcholinesterase (AChE, EC 188.8.131.52). Increasing resistance to many preparations has led to the search for more effective treatments. Tea Tree oil, otherwise known as Melaleuca oil, has been added to several preparations as an alternative treatment of head lice infestations. In this study two major constituents of Tea Tree oil, 1,8-cineole and terpinen-4-ol, were shown to inhibit acetylcholinesterase at IC50 values (inhibitor concentrations required to give 50% inhibition) of 0.04 and 10.30 mM, respectively. Four samples of Tea Tree oil tested (Tisserand, Body Treats, Main Camp and Irish Health Culture Association Pure Undiluted) showed anticholinesterase activity at IC50 values of 0.05, 0.10, 0.08 and 0.11 microL mL(-1), respectively. The results supported the hypothesis that the insecticidal activity of Tea Tree oil was attributable, in part, to the anticholinesterase activity of Tea Tree oil.
D'Auria, F D; Laino, L; Strippoli, V; Tecca, M; Salvatore, G; Battinelli, L; Mazzanti, G
The antifungal activity of Melaleuca alternifolia Maiden (Myrtaceae) essential oil against yeasts (Candida spp., Schizosaccharomyces pombe, Debaryomyces hansenii) and dermatophytes (Microsporum spp. and Tricophyton spp.) is reported. We focused on the ability of tea tree oil to inhibit Candida albicans conversion from the yeast to the pathogenic mycelial form. Moreover we carried out broth microdilution test and contact tests to evaluate the killing time. M. alternifolia essential oil inhibited the conversion of C. albicans from yeast to the mycelial form at a concentration of 0.16% (v/v). The minimum inhibitory concentrations (MICs) ranged from 0.12% to 0.50% (v/v) for yeasts and 0.12% to 1% (v/v) for dermatophytes; the cytocidal activity was generally expressed at the same concentration. These results, if considered along with the lipophilic nature of the oil which enables it to penetrate the skin, suggest it may be suitable for topical therapeutic use in the treatment of fungal mucosal and cutaneous infections.
Biju, S S; Ahuja, A; Khar, R K; Chaudhry, R
The effect of pH on the antimicrobial activity of Melaleuca alternifolia essential oil formulations was studied. Microemulsions, liposomal dispersions, multiple emulsions and a colloidal bed of sterile clay were formulated using 5% w/w of tea tree oil. A number of formulations were prepared at various pH values (5.0, 5.5, 6.0, 6.5, and 7.0). Thermal stability studies showed that the formulations were stable for more than eight months. Agar dilution tests showed MICs of 1.0% v/v S. aureus and S. epidermidis. In the broth dilution test, MBC of the oil for P. acnes was 0.5% v/v. MIC and MBC values were comparable to those of non-formulated tea tree oil, indicating that tea tree oil retained its activity in the above-mentioned formulations. The microbiological evaluation showed that the formulations containing 5% w/w tea tree oil had a maximum effect at pH 5.5.
Weseler, A; Geiss, H K; Saller, R; Reichling, J
The lipophilic yeast Malassezia pachydermatis is part of the normal skin flora of most warm-blooded organisms. In a number of surveys it could be demonstrated that this yeast species might be involved in different skin diseases like seborrhoeic dermatitis, especially in dogs and cats. In order to look for an alternative therapeutic agent to the commonly used antimycotic and antiseptic synthetic substances the in vitro activity of Australian tea tree oil, the essential oil of Melaleuca alternifolia, against several strains of Malassezia pachydermatis was examined. All tested strains showed remarkably high susceptibility to tea tree oil. With these results the excellent antibacterial activity of tea tree oil is extended to a new group of fungal pathogens colonizing mainly mammals' skin. During the last ten years there was an increasing popularity of tea tree oil containing human health care products. The presented data open up new horizons for this essential oil as a promising alternative agent for topical use in veterinary medicine as well.
Yu, D; Wang, J; Shao, X; Xu, F; Wang, H
The essential oil of Melaleuca alternifolia (tea tree) has been evaluated as a potential eco-friendly antifungal agent against Botrytis cinerea. In this study, we investigated the antifungal activity and mode of action of tea tree oil (TTO) and its components against B. cinerea. Of the components we tested in contact phase, terpinen-4-ol had the highest antifungal activity, followed by TTO, α-terpineol, terpinolene, then 1,8-cineole. As one of characteristic components of TTO, terpinen-4-ol treatment led to pronounced alterations in mycelial morphology, cellular ultrastructure, membrane permeability under scanning electron microscope, transmission electron microscope and fluorescent microscope, and also reduced the ergosterol content of fungi. As another characteristic component, 1,8-cineole caused serious intracellular damage but only slightly affected B. cinerea otherwise. When terpinen-4-ol and 1,8-cineole were used together, the synergistic antifungal activity was significantly higher than either component by itself. The results of our study confirmed that terpinen-4-ol and 1,8-cineole act mainly on the cell membranes and organelles of B. cinerea, respectively, and when combined are similar to TTO in antifungal activity due to their differences. Understanding the mechanism of terpinen-4-ol and 1,8-cineole antifungal action to B. cinerea is helpful for investigation on their synergistic effect and explaining antifungal action modes of TTO. © 2015 The Society for Applied Microbiology.
Klauck, V; Pazinato, R; Stefani, L M; Santos, R C; Vaucher, R A; Baldissera, M D; Raffin, R; Boligon, A; Athayde, M; Baretta, D; Machado, G; DA Silva, A S
This study aimed to evaluate the insecticidal and repellent effects of tea tree, Melaleuca alternifolia (Myrtales: Myrtaceae), and andiroba, Carapa guianensis (Sapindales: Meliaceae), essential oils on two species of fly. For in vitro studies, free-living adult flies were captured and reared in the laboratory. To evaluate the insecticidal effects of the oils, adult flies of Haematobia irritans (L.) and Musca domestica L. (both: Diptera: Muscidae) were separated by species in test cages (n = 10 per group), and subsequently tested with oils at concentrations of 1.0% and 5.0% using a negative control to validate the test. Both oils showed insecticidal activity. Tea tree oil at a concentration of 5.0% was able to kill M. domestica with 100.0% efficacy after 12 h of exposure. However, the effectiveness of andiroba oil at a concentration of 5.0% was only 67.0%. The insecticidal efficacy (100.0%) of both oils against H. irritans was observed at both concentrations for up to 4 h. The repellency effects of the oils at concentrations of 5.0% were tested in vivo on Holstein cows naturally infested by H. irritans. Both oils demonstrated repellency at 24 h, when the numbers of flies on cows treated with tea tree and andiroba oil were 61.6% and 57.7%, respectively, lower than the number of flies on control animals. It is possible to conclude that these essential oils have insecticidal and repellent effects against the species of fly used in this study.
Herbs and minerals have been used in clinical dermatology for hundreds of years and herbal ingredients are becoming increasingly popular with the public in treatment of various dermatological conditions characterised by inflammation and pruritus. The aim of this study was to compare the efficacy of traditional topical therapeutic agents with a moderate potency topical glucocorticoid on experimental contact dermatitis and contact urticaria. The effects of ichthammol 10% pet, zinc oxide 20% pet, camphor 20% pet, levomenthol 10% pet, tea tree oil 20 or 50% and clobetason butyrate 0.05% ointment were studied in the following experimental models: elicitation of allergic contact dermatitis to nickel, irritant contact dermatitis to benzalkonium chloride, and in immediate reactions to histamine and benzoic acid (non-immunological contact utricaria) respectively. Delayed reactions were evaluated using a clinical scoring system and immediate reactions were estimated by planimetry. Histamine-induced pruritus was evaluated using VAS. Tea tree oil reduced allergic contact dermatitis by 40.5% (p = 0.003), zinc oxide by 17.4% (p = 0.04) and clobetason butyrate by 23.5% (p = 0.01). Zinc oxide reduced histamine induced flare by 18.5% (p = 0.01), ichthammol by 19.2% (p = 0.02) and clobetason butyrate by 44.1% (p = 0.02). Irritant contact dermatitis and non-immunological contact urticaria were not influenced by the pre-treatments. Pruritus induced by histamine also remained unchanged. In conclusion, tea tree oil seems to be a more effective anti-eczematic agent than zinc oxide and clobetasone butyrate, while clobetasone butyrate is superior to both ichthammol and zinc oxide in topical treatment of urticarial reactions.
Steverding, Dietmar; Morgan, Edward; Tkaczynski, Patrick; Walder, Foster; Tinsley, Richard
Gyrodactylus spp. infections of commercially farmed fishes are responsible for significant economic losses. Existing treatments have proved uneconomic, stressful to the fishes, and ecologically damaging. Essential oils are naturally occurring compounds that exhibit a wide range of anti-microbial and anti-fungal activities. This study explored the possibility of using Australian tea tree (Melaleuca alternifolia) oil (TTO) to treat Gyrodactylus spp. infection on the three-spined stickleback Gasterosteus aculeatus. In the presence of 0.01 % Tween 80 as an emulsifier, TTO treatments at concentrations between 3 and 30 ppmv (parts per million by volume) lowered the prevalence and significantly reduced the parasite burden of sticklebacks naturally infected with Gyrodactylus spp. In addition, Tween 80 alone exhibited parasiticidal activity against Gyrodactylus spp. These findings show the potential of TTO in combination with Tween 80 as an effective treatment of Gyrodactylus spp. infection of fishes.
Di Campli, Emanuela; Di Bartolomeo, Soraya; Delli Pizzi, Patricia; Di Giulio, Mara; Grande, Rossella; Nostro, Antonia; Cellini, Luigina
Head lice infestation is an emerging social problem in undeveloped and developed countries. Because of louse resistance increasing, several long-used insecticidal compounds have lost their efficacy, and alternatives, such as essential oils, have been proposed to treat this parasitic infestation. The present study investigated the efficacy of two natural substances: tea tree (Melaleuca alternifolia) oil and nerolidol (3,7,11-trimethyl-1,6,10-dodecatrien-3-ol) against lice and its eggs. Products were used alone and in combination (ratio 1:1 and 1:2) from 8 % dilution. The in vitro effect of natural substances at different concentrations were evaluated against 69 head lice (adults and nymphs) and 187 louse eggs collected from school children in Chieti-Pescara (Central Italy) over a 6-month period. The lice mortality was evaluated for 24 h by a stereo light microscope. The ovicidal activity was monitored by microscopic inspections for 15 days. Tea tree oil was more effective than nerolidol against head lice with 100 % mortality at 30 min and 1 % concentration. On the contrary, nerolidol expressed a more pronounced ovicidal activity inducing the failure of 50 % of the eggs to hatch at 1 % concentration after 4 days; the same effect was achieved by using a twice concentration of tea tree oil. The association of the two substances both in ratios 1:1 and 1:2 combined efficaciously their insecticidal and ovicidal effect; in particular, the ratio 1:2 (tea tree oil 0.5 % plus nerolidol 1 %) acted producing both the death of all head lice at 30 min and the abortive effect of louse eggs after 5 days. These results offer new potential application of natural compounds and display a promising scenario in the treatment of pediculosis resistant cases. The development of novel pediculicides containing essential oils could be, in fact, an important tool to control the parasitic infestation.
Tea tree oil is a popular ingredient in complementary medicines and beauty products. This literature review reveals some evidence of efficacy as an antiseptic, antibacterial and antifungal in topical application but also highlights dermatitis as a potential side-effect.
Henley, Derek V; Lipson, Natasha; Korach, Kenneth S; Bloch, Clifford A
Most cases of male prepubertal gynecomastia are classified as idiopathic. We investigated possible causes of gynecomastia in three prepubertal boys who were otherwise healthy and had normal serum concentrations of endogenous steroids. In all three boys, gynecomastia coincided with the topical application of products that contained lavender and tea tree oils. Gynecomastia resolved in each patient shortly after the use of products containing these oils was discontinued. Furthermore, studies in human cell lines indicated that the two oils had estrogenic and antiandrogenic activities. We conclude that repeated topical exposure to lavender and tea tree oils probably caused prepubertal gynecomastia in these boys.
Sailer, R; Berger, T; Reichling, J; Harkenthal, M
The essential tea tree oil has been widely used in modern medicine and cosmetics in recent years. Although there are clinical data to show the benefical effects (e.g. antiseptic, antimicrobial, antioxidative) of this oil, dose-response studies are lacking. This paper reviews the clinical use of this essential oil, especially as a topical application.
Li, Wen-Ru; Li, Hai-Ling; Shi, Qing-Shan; Sun, Ting-Li; Xie, Xiao-Bao; Song, Bin; Huang, Xiao-Mo
Tea tree oil (TTO) is a yellow liquid extracted from Melaleuca alternifolia. Although the antimicrobial activity of TTO has been known for a long time, its specific antimicrobial effects and mechanism underlying these remain poorly characterized. The present study investigated the chemical composition of TTO and the dynamics and mechanism of its antimicrobial activities in two bacterial and two fungal strains. Gas chromatography-mass spectrometry analysis identified alkenes and alcohols as the main constituents of TTO. Terpinen-4-ol was the most abundant individual component, accounting for approximately 23 % of the TTO. Poisoned food technique assessment showed that the minimum inhibitory concentrations of TTO for bacterial strains (Escherichia coli and Staphylococcus aureus) and fungal strains (Candida albicans and Aspergillus niger) were 1.08 and 2.17 mg/mL, respectively. Antimicrobial dynamic curves showed that with increasing concentrations of TTO, the rate of cell killing and the duration of growth lag phase increased correspondingly. These data indicated that TTO produced concentration and time-dependent antimicrobial effects. The minimum bactericidal and fungicidal concentrations of TTO were 2.17, 4.34, and 4.34 against E. coli, S. aureus, and C. albicans, respectively. However, A. niger conidia were not completely eradicated, even after 3 days in the presence of 17.34 mg/mL TTO. Transmission electron microscopy images indicated that TTO penetrated the cell wall and cytoplasmic membrane of all the tested bacterial and fungal strains. TTO may also penetrate fungal organelle membrane. These findings indicated that TTO maybe exerts its antimicrobial effects by compromising the cell membrane, resulting in loss of the cytoplasm and organelle damage, which ultimate leads to cell death.
Avonto, Cristina; Chittiboyina, Amar G; Wang, Mei; Vasquez, Yelkaira; Rua, Diego; Khan, Ikhlas A
Tea tree oil (TTO) is an essential oil obtained from the leaves of Melaleuca alternifolia, M. linariifolia, or M. dissitiflora. Because of the commercial importance of TTO, substitution or adulteration with other tea tree species (such as cajeput, niaouli, manuka, or kanuka oils) is common and may pose significant risks along with perceived health benefits. The distinctive nature, qualitative and quantitative compositional variation of these oils, is responsible for the various pharmacological as well as adverse effects. Authentic TTOs (especially aged ones) have been identified as potential skin sensitizers, while reports of adverse allergic reactions to the other tea trees essential oils are less frequent. Chemical sensitizers are usually electrophilic compounds, and in chemico methods have been developed to identify skin allergens in terms of their ability to bind to biological nucleophiles. However, little information is available on the assessment of sensitization potential of mixtures, such as essential oils, due to their complexity. In the present study, 10 "tea tree" oils and six major TTO constituents have been investigated for their sensitization potential using a fluorescence in chemico method. The reactivity of authentic TTOs was found to correlate with the age of the oils, while the majority of nonauthentic TTOs were less reactive, even after aging. Further thio-trapping experiments with DCYA and characterization by UHPLC-DAD-MS led to the identification of several possible DCYA-adducts which can be used to deduce the structure of the candidate reactive species. The major TTO components, terpinolene, α-terpinene, and terpinene-4-ol, were unstable under accelerated aging conditions, which led to the formation of several DCYA-adducts.
Caelli, M; Porteous, J; Carson, C F; Heller, R; Riley, T V
The combination of a 4% tea tree oil nasal ointment and 5% tea tree oil body wash was compared with a standard 2% mupirocin nasal ointment and triclosan body wash for the eradication of methicillin-resistant Staphylococcus aureus carriage. The tea tree oil combination appeared to perform better than the standard combination, although the difference was not statistically significant due to the small number of patients.
Christoffers, Wietske Andrea; Blömeke, Brunhilde; Coenraads, Pieter-Jan; Schuttelaar, Marie-Louise Anna
Tea tree oil is used as a natural remedy, but is also a popular ingredient in household and cosmetic products. Oxidation of tea tree oil results in degradation products, such as ascaridole, which may cause allergic contact dermatitis. To identify the optimal patch test concentration for ascaridole, and to investigate the relationship between a positive reaction to ascaridole and a positive reaction to oxidized tea tree oil. Three hundred and nineteen patients with eczema were patch tested with ascaridole 1%, 2%, and 5%, and 250 patients were patch tested with oxidized tea tree oil 5%. Readings were performed on D3 and D7 according to a patch test calibration protocol. With an increasing ascaridole test concentration, the frequency of positive reactions increased: ascaridole 1%, 1.4%; ascaridole 2%, 5.5%; and ascaridole 5%, 7.2%. However, the frequencies of irritant and doubtful reactions also increased, especially for ascaridole 5%. A positive reaction to ascaridole was related to a positive reaction to tea tree oil. This study is in support of ascaridole being a sensitizer. We recommend patch testing with ascaridole at 2%. The finding that every positive reaction to oxidized tea tree oil is accompanied by a positive reaction to ascaridole suggests that ascaridole might be a contact allergen in oxidized tea tree oil. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Dryden, M S; Dailly, S; Crouch, M
Two topical MRSA eradication regimes were compared in hospital patients: a standard treatment included mupirocin 2% nasal ointment, chlorhexidine gluconate 4% soap, silver sulfadiazine 1% cream versus a tea tree oil regimen, which included tea tree 10% cream, tea tree 5% body wash, both given for five days. One hundred and fourteen patients received standard treatment and 56 (49%) were cleared of MRSA carriage. One hundred and ten received tea tree oil regimen and 46 (41%) were cleared. There was no significant difference between treatment regimens (Fisher's exact test; P = 0.0286). Mupirocin was significantly more effective at clearing nasal carriage (78%) than tea tree cream (47%; P = 0.0001) but tea tree treatment was more effective than chlorhexidine or silver sulfadiazine at clearing superficial skin sites and skin lesions. The tea tree preparations were effective, safe and well tolerated and could be considered in regimens for eradication of MRSA carriage.
Morris, Marilyn C; Donoghue, Aaron; Markowitz, Jennifer A; Osterhoudt, Kevin C
A 4-year-old boy ingested a small quantity of tea tree oil. Within 30 minutes, he became ataxic and shortly thereafter progressed to unresponsiveness; he was endotracheally intubated by paramedics. His neurologic status improved gradually over 10 hours, and he remains well on follow-up. Tea tree oil is an increasingly popular topical antiseptic that is available in a wide variety of products, often without warning labels. Healthcare providers should be aware of the common uses of tea tree oil, as well as its potential toxicity.
Grando, Thirssa H; Baldissera, Matheus D; Gressler, Lucas T; de Sá, Mariângela Facco; Bortoluzzi, Bruna N; Schafer, Andressa S; Ebling, Rafael C; Raffin, Renata P; Santos, Roberto C V; Stefani, Lenita M; Vaucher, Rodrigo; Leal, Marta L R; Monteiro, Silvia G
Gastrointestinal parasites are one of the biggest health problems faced in sheep, mainly due to their pathogenicity and resistance to drugs used to control these parasites. Thus, the following study aimed to assess the anthelmintic efficacy of Melaleuca alternifolia against Haemonchus contortus in gerbils (Meriones unguiculatus) experimentally infected. Three treatments were tested: M. alternifolia essential oil, popularly known as tea tree oil (TTO), a solid lipid nanocarrier made with essential oil of Melaleuca (nanoTTO), and terpinen-4-ol (terp-4-ol). In vivo studies were performed by determining the mean worm burden of H. contortus in gerbils TTO (0.75 mL/kg); nanoTTO (0.5 mL/kg) and terp-4-ol (0.5 mL l/kg) were able to reduce 46.36%; 48.64%, and 43.18% worm burden, respectively. H. contortus increased alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels, as demonstrated by liver injury. It was found that the TTO, nanoTTO, and terp-4-ol were not toxic to liver and kidneys since hepatic and renal functions were not affected. Moreover, terp-4-ol was able to prevent increased levels of seric AST and ALT in infected animals, indicating a hepatoprotective effect. Thus, our results indicate that TTO, nanoTTO, and terp-4-ol are safe and efficient against H. contortus infection in gerbils, and possibly the terp-4-ol may be considered the compound present in the Melaleuca alternifolia responsible for parasitic action against H. contortus.
Rutherford, Tim; Nixon, Rosemary; Tam, Mei; Tate, Bruce
Tea tree oil use is increasing, with considerable interest in it being a 'natural' antimicrobial. It is found in many commercially available skin and hair care products in Australia. We retrospectively reviewed our patch test data at the Skin and Cancer Foundation Victoria over a 4.5-year period and identified 41 cases of positive reactions to oxidized tea tree oil of 2320 people patch-tested, giving a prevalence of 1.8%. The tea tree oil reaction was deemed relevant to the presenting dermatitis in 17 of 41 (41%) patients. Of those with positive reactions, 27 of 41 (66%) recalled prior use of tea tree oil and eight of 41 (20%) specified prior application of neat (100%) tea tree oil. Tea tree oil allergic contact dermatitis is under-reported in the literature but is sufficiently common in Australia to warrant inclusion of tea tree oil, at a concentration of 10% in petrolatum, in standard patch-test series. Given tea tree oil from freshly opened tea tree oil products elicits no or weak reactions, oxidized tea tree oil should be used for patch testing.
Richards, David B; Wang, George S; Buchanan, Jennie A
Tea tree oil is an essential oil containing a mixture of aromatic hydrocarbons. We describe an 18-month-old male patient who ingested tea tree oil, developed central nervous system depression, respiratory distress, and received early emergency department treatment with surfactant. Early treatment of hydrocarbon pneumonitis with surfactant has not been previously described. Early administration of surfactant should be further evaluated for treatment of hydrocarbon aspiration.
Nogueira, M N M; Aquino, S G; Rossa Junior, C; Spolidorio, D M P
Tea tree oil (TTO) is an essential oil with anti-inflammatory properties, steam distilled from the plant Melaleuca alternifolia. We investigated the immunomodulatory properties of TTO and its components (terpinen-4-ol and alpha-terpineol) using lipopolysaccharide (LPS)-stimulated macrophages. The ability of TTO, terpinen-4-ol and alpha-terpineol to modulate the macrophage response to bacterial LPS stimulation was assessed by ELISA for tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-6 and IL-10 cytokine production and by western blotting for the activation of nuclear factor kappa B (NF-κB) and p38 mitogen-activated protein kinase (MAPK) signaling, which are associated with the expression of pro-inflammatory cytokines. We used a human monocytic cell line (U937) differentiated into macrophages. LPS induced the production of all cytokines, and TTO and its components significantly reduced the production of IL-1β, IL-6 and IL-10. The production of TNF-α was not affected by either TTO or its major components. The modulation of cytokine production was not mediated by changes in NF-κB or p38 MAPK activation. TTO, terpinen-4-ol and alpha-terpineol can suppress the production of inflammatory mediators in LPS-stimulated human macrophages; this inhibition was mediated by interfering with the NF-kB, p38 or ERK MAPK pathways.
Thomas, Jackson; Carson, Christine F.; Peterson, Greg M.; Walton, Shelley F.; Hammer, Kate A.; Naunton, Mark; Davey, Rachel C.; Spelman, Tim; Dettwiller, Pascale; Kyle, Greg; Cooper, Gabrielle M.; Baby, Kavya E.
Globally, scabies affects more than 130 million people at any time. In the developed world, outbreaks in health institutions and vulnerable communities result in a significant economic burden. A review of the literature demonstrates the emergence of resistance toward classical scabicidal treatments and the lack of effectiveness of currently available scabicides in reducing the inflammatory skin reactions and pyodermal progression that occurs in predisposed patient cohorts. Tea tree oil (TTO) has demonstrated promising acaricidal effects against scabies mites in vitro and has also been successfully used as an adjuvant topical medication for the treatment of crusted scabies, including cases that did not respond to standard treatments. Emerging acaricide resistance threatens the future usefulness of currently used gold standard treatments (oral ivermectin and topical permethrin) for scabies. The imminent development of new chemical entities is doubtful. The cumulative acaricidal, antibacterial, antipruritic, anti-inflammatory, and wound healing effects of TTO may have the potential to successfully reduce the burden of scabies infection and the associated bacterial complications. This review summarizes current knowledge on the use of TTO for the treatment of scabies. On the strength of existing data for TTO, larger scale, randomized controlled clinical trials are warranted. PMID:26787146
Thomas, Jackson; Carson, Christine F; Peterson, Greg M; Walton, Shelley F; Hammer, Kate A; Naunton, Mark; Davey, Rachel C; Spelman, Tim; Dettwiller, Pascale; Kyle, Greg; Cooper, Gabrielle M; Baby, Kavya E
Globally, scabies affects more than 130 million people at any time. In the developed world, outbreaks in health institutions and vulnerable communities result in a significant economic burden. A review of the literature demonstrates the emergence of resistance toward classical scabicidal treatments and the lack of effectiveness of currently available scabicides in reducing the inflammatory skin reactions and pyodermal progression that occurs in predisposed patient cohorts. Tea tree oil (TTO) has demonstrated promising acaricidal effects against scabies mites in vitro and has also been successfully used as an adjuvant topical medication for the treatment of crusted scabies, including cases that did not respond to standard treatments. Emerging acaricide resistance threatens the future usefulness of currently used gold standard treatments (oral ivermectin and topical permethrin) for scabies. The imminent development of new chemical entities is doubtful. The cumulative acaricidal, antibacterial, antipruritic, anti-inflammatory, and wound healing effects of TTO may have the potential to successfully reduce the burden of scabies infection and the associated bacterial complications. This review summarizes current knowledge on the use of TTO for the treatment of scabies. On the strength of existing data for TTO, larger scale, randomized controlled clinical trials are warranted. © The American Society of Tropical Medicine and Hygiene.
de Groot, Anton C; Schmidt, Erich
In this article, contact allergy to, and the chemical composition of, tea tree oil (TTO) are reviewed. This essential oil is a popular remedy for many skin diseases, and may be used as neat oil or be present in cosmetics, topical pharmaceuticals and household products. Of all essential oils, TTO has caused most (published) allergic reactions since the first cases were reported in 1991. In routine testing, prevalences of positive patch test reactions have ranged from 0.1% to 3.5%. Nearly 100 allergic patients have been described in case reports and case series. The major constituents of commercial TTO are terpinen-4-ol, γ-terpinene, 1,8-cineole, α-terpinene, α-terpineol, p-cymene, and α-pinene. Fresh TTO is a weak to moderate sensitizer, but oxidation increases its allergenic potency. The major sensitizers appear to be ascaridole, terpinolene, α-terpinene, 1,2,4-trihydroxymenthane, α-phellandrene, and limonene. The clinical picture of allergic contact dermatitis caused by TTO depends on the products used. Most reactions are caused by the application of pure oil; cosmetics are the culprits in a minority of cases. Patch testing may be performed with 5% oxidized TTO. Co-reactivity to turpentine oil is frequent, and there is an overrepresentation of reactions to fragrance mix I, Myroxylon pereirae, colophonium, and other essential oils.
May, J; Chan, C H; King, A; Williams, L; French, G L
Tea tree oil has recently emerged as an effective topical antimicrobial agent active against a wide range of organisms. Tea tree oil may have a clinical application in both the hospital and community, especially for clearance of methicillin-resistant Staphylococcus aureus (MRSA) carriage or as a hand disinfectant to prevent cross-infection with Gram-positive and Gramnegative epidemic organisms. Our study, based on the time-kill approach, determined the kill rate of tea tree oil against several multidrug-resistant organisms, including MRSA, glycopeptide-resistant enterococci, aminoglycoside-resistant klebsiellae, Pseudomonas aeruginosa and Stenotrophomonas maltophilia, and also against sensitive microorganisms. The study was performed with two chemically different tea tree oils. One was a standard oil and the other was Clone 88 extracted from a specially bred tree, which has been selected and bred for increased activity and decreased skin irritation. Our results confirm that the cloned oil had increased antimicrobial activity when compared with the standard oil. Most results indicated that the susceptibility pattern and Gram reaction of the organism did not influence the kill rate. A rapid killing time (less than 60 min) was achieved with both tea tree oils with most isolates, but MRSA was killed more slowly than other organisms.
Flaxman, Deborah; Griffiths, Peter
In vitro studies show that tea tree oil is capable of killing methicillin-resistant Staphylococcus aureus (MRSA) in a laboratory setting. This review of randomized controlled trials (RCTs) was undertaken to find out whether it is effective at eradicating MRSA colonization compared to standard mupirocin-based regimens in colonized patients. A wide range of databases and internet sources were searched to identify published and unpublished studies. Two RCTs were found that researched the effectiveness of tea tree oil preparations against MRSA. One small RCT (n = 30) showed a large but non-significant improvement at eradicating MRSA compared to traditional treatment, whereas a larger study (n = 224) demonstrated little difference in rates of eradication overall (41% for tea tree and 49% for mupirocin, p = 0.286). However, the larger study found that those with nasal colonization receiving a tea tree regimen were more likely to remain colonized with MRSA in the nose (absolute risk increase 31%, p<0.001). Currently there is insufficient evidence to support the routine use of tea tree oil in clinical practice for eradication of MRSA colonization.
Mozelsio, Nancy B; Harris, Kathleen E; McGrath, Kris G; Grammer, Leslie C
Australian tea tree oil has been used as a veterinary antiseptic for many years and, more recently, has been extended into human use. There have been many reports of allergic contact dermatitis and toxicity reactions, but it has never been implicated in immediate systemic hypersensitivity reactions. A 38-year-old man experienced immediate flushing, pruritus, throat constriction, and lightheadedness after topical application of tea tree oil. Our purpose was to determine whether this represented an immunoglobulin E (IgE)--mediated reaction. Skin-prick and intradermal testing was performed, as well as enzyme-linked immunosorbent assays for specific IgG and IgE against tea tree oil. The patient had a positive wheal and flare reaction on intradermal testing with tea tree oil. All five patient controls were negative on skin testing. No specific IgG or IgE was detected. We present the first reported case of an immediate systemic hypersensitivity reaction occurring after topical application of Australian tea tree oil, confirmed by positive wheal and flare reaction on skin testing.
Zhang, Xiao-feng; Chen, Di-yun; Peng, Yan; Liu, Yong-sheng; Xiong, Xue-ying
In order to explore how the modification of succinic acid improves the adsorption of tea oil tree sawdust for uranium, the tea oil tree sawdust was modified by succinic acid, after the pretreatments of crushing, screening, alkalization and acidification. Infrared analysis indicated carboxylic acid groups and ester groups were added to the sawdust after modification, and scanning electron microscope demonstrated after modification the appearance of tea oil tree sawdust was transferred from the structure like compact and straight stripped into the structure like loose and wrinkled leaves, which meant modification increased its inner pores. By the static experiments, effects of reaction time between adsorbent and solvent, dosage of adsorbent, temperature, pH value and initial concentration of uranium were investigated. The results showed that after the modification by succinic acid, the absorption rate of tea oil tree sawdust for uranium increased significantly by about 20% in 12.5 mg · L(-1) initial concentration uranium solution. Adsorption equilibrium was achieved within 180 min, and the kinetic data can be well described by the pseudo-second-order kinetic model. The experimental adsorption isotherm followed the Langmuir and Freundlich models. In addition, the maximum adsorption amounts of tea oil tree sawdust after modification calculated from Langmuir equation raised from 21.413 3 to 31.545 7 mg · g(-1) at 35°C and pH 4.0.
Lou, Weiping; Sun, Shanlei
This paper proposes a method to design freezing damage policy-based agricultural insurance contracts for tea trees (an economic crop) in the Zhejiang Province of China, using a weather index. Data of economic losses caused by freezing damage, and the beginning dates of tea plucking (BDTP) from the Agricultural Bureau of each county in Zhejiang Province and tea planters, and meteorological observations were collected to establish the prediction model for BDTP, and to determine the relationship between economic loss rates caused by freezing damage at or before BDTP, and the minimum temperatures for "Wuniuzao," "Longjing-43," and "Jiukeng" teas. Based on the information diffusion theoretical model, occurrence probabilities of BDTP from 1 February to 20 April and lower temperatures at different levels are calculated. Then, the insurance premium rates of the three tea tree species can be estimated. Lastly, the tea tree freezing damage insurance contracts are designed, combining the advantages of regional yield-based index insurance and weather-based index insurance.
Bezdjian, Aren; Mujica-Mota, Mario A; Azzi, Michelle; Daniel, Sam J
The aim of the present study is to examine the effects of tea tree oil on hearing function and cochlear morphology after intratympanic administration in a chinchilla animal model. Nine chinchillas received intratympanic injection of 3% tea tree oil dissolved in olive oil in one ear, whereas the contralateral control ear received olive oil only. Outcome measures included auditory brainstem responses conducted before treatment and at 10 days and 30 days following the injection. Post-mortem cochlear morphology was assessed using scanning electron microscopy. At 10 and 30 days following the injection, there was no significant change in auditory brain response thresholds at 8, 16, 20 or 25kHz. Scanning electron microscopy imaging showed no damage to auditory hair cells. Tea tree oil (3%) does not appear to be ototoxic in a chinchilla animal model. Future preclinical and clinical studies are required to establish the effectiveness of TTO in treating otitis. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.
Wong, Yong Foo; West, Rachel N; Chin, Sung-Tong; Marriott, Philip J
This work demonstrates the potential of fast multiple heart-cut enantioselective multidimensional gas chromatography (GC-eGC) and enantioselective comprehensive two-dimensional gas chromatography (eGC×GC), to perform the stereoisomeric analysis of three key chiral monoterpenes (limonene, terpinen-4-ol and α-terpineol) present in tea tree oil (TTO). In GC-eGC, separation was conducted using a combination of mid-polar first dimension ((1)D) column and a chiral second dimension ((2)D) column, providing interference-free enantioresolution of the individual antipodes of each optically active component. A combination of (1)D chiral column and (2)D polar columns (ionic liquid and wax phases) were tested for the eGC×GC study. Quantification was proposed based on summation of two major modulated peaks for each antipode, displaying comparable results with those derived from GC-eGC. Fast chiral separations were achieved within 25min for GC-eGC and<20min for eGC×GC, while ensuring adequate interference-free enantiomer separation. The suitability of using these two enantioselective multidimensional approaches for the routine assessment of chiral monoterpenes in TTO was evaluated and discussed. Exact enantiomeric composition of chiral markers for authentic TTOs was proposed by analysing a representative number of pure TTOs sourced directly from plantations of known provenance in Australia. Consistent enantiomeric fractions of 61.6±1.5% (+):38.4±1.5% (-) for limonene, 61.7±1.6% (+):38.3±1.6% (-) for terpinen-4-ol and 79.6±1.4% (+):20.4±1.4% (-) for α-terpineol were obtained for the 57 authentic Australian TTOs. The results were compared (using principle component analysis) with commercial TTOs (declared as derived from Melaleuca alternifolia) obtained from different continents. Assessing these data to determine adulteration, or additives that affect the enantiomeric ratios, in commercially sourced TTOs is discussed. The proposed method offers distinct advantages over e
Conventional GC/MS, chiral GC/MS and chemometric techniques were used to evaluate a large set of tea tree oils (TTO) and commercial products purported to contain tea tree oils. Fifty-seven known provenance pure Australian tea tree oils and forty-seven commercial TTO products were investigated. Twent...
The aroma of various plant essential oils has been shown to enhance the mating competitiveness of males of the Mediterranean fruit fly (medfly), Ceratitis capitata (Wiedemann). Laboratory observations revealed that male medflies show strong short-range attraction to tea tree oil (TTO hereafter) deri...
SALVATORI, C.; BARCHI, L.; GUZZO, F.; GARGARI, M.
SUMMARY The study evaluated the antibacterial and anti-inflammatory efficacy, domiciliary oral hygiene, of a mouthrinse containing Tea Tree Oil (TTO) comparing it with two mouthrinses containing chlorhexidine 0,12% respectively and essential oils, and a placebo. Materials and methods A pilot study, randomized 4 × 4, controlled, cross-over, double-blind. 16 subjects with gingivitis (7 males and 9 females) aged 21–37 years, were randomly divided into four groups based on mouthwash that had to be used for domiciliary oral hygiene: mouthwash with essential oils, mouthwash with chlorhexidine 0,12 %, mouthwash containig tea tree oil and mouthwash placebo. Clinical evaluation was performed by: Full Mouth Plaque Score (FMPS), Full Mouth Bleeding Score (FMBS), Gingival Index (GI), discolorations, language examination and alteration of taste. The data were recorded before and 2 weeks after treatment. Results Statistical analysis shows that treatments with tea tree oil, essential oils and chlorhexidine are effective. Comparing treatments should be noted that the tea tree oil gives a greater improvement in the GI and FMBS, while it is the least effective in the control of bacterial plaque. Conclusion Although further studies are needed, the anti-inflammatory properties of the mouthwash made from TTO would seem to be a valuable non-toxic adjunct in the management of gingivitis. PMID:28757937
Hadaś, Edward; Derda, Monika; Cholewiński, Marcin
Eye diseases caused by amoebae from the genus Acanthamoeba are usually chronic and severe, and their treatment is prolonged and not very effective. The difficulties associated with therapy have led to attempts at finding alternative treatment methods. Particularly popular is searching for cures among drugs made of plants. However, no substances with total efficacy in treating Acanthamoeba keratitis have been identified.Results of our semi in vivo studies of tea tree oil simulating eyeball infection demonstrated 100% effectiveness in the case of both trophozoites and cysts of amoebae from the genus Acanthamoeba. The action of tea tree oil indicates that this is the first substance with a potential ability to quickly and effectively remove the amoebae from the eye. Tea tree oil has the ability to penetrate tissues, which allows it to destroy amoebae in both the shallow and deep layers of the cornea. The present research into the use of tea tree oil in the therapy of Acanthamoeba infection is the first study of this type in parasitology. It offers tremendous potential for effective treatment of Acanthamoeba keratitis and other diseases caused by these protozoa.
Salvatori, C; Barchi, L; Guzzo, F; Gargari, M
The study evaluated the antibacterial and anti-inflammatory efficacy, domiciliary oral hygiene, of a mouthrinse containing Tea Tree Oil (TTO) comparing it with two mouthrinses containing chlorhexidine 0,12% respectively and essential oils, and a placebo. A pilot study, randomized 4 × 4, controlled, cross-over, double-blind. 16 subjects with gingivitis (7 males and 9 females) aged 21-37 years, were randomly divided into four groups based on mouthwash that had to be used for domiciliary oral hygiene: mouthwash with essential oils, mouthwash with chlorhexidine 0,12 %, mouthwash containig tea tree oil and mouthwash placebo. Clinical evaluation was performed by: Full Mouth Plaque Score (FMPS), Full Mouth Bleeding Score (FMBS), Gingival Index (GI), discolorations, language examination and alteration of taste. The data were recorded before and 2 weeks after treatment. Statistical analysis shows that treatments with tea tree oil, essential oils and chlorhexidine are effective. Comparing treatments should be noted that the tea tree oil gives a greater improvement in the GI and FMBS, while it is the least effective in the control of bacterial plaque. Although further studies are needed, the anti-inflammatory properties of the mouthwash made from TTO would seem to be a valuable non-toxic adjunct in the management of gingivitis.
Satchell, Andrew C; Saurajen, Anne; Bell, Craig; Barnetson, Ross St C
Tea tree oil has been shown to have activity against dermatophytes in vitro. We have conducted a randomized, controlled, double-blinded study to determine the efficacy and safety of 25% and 50% tea tree oil in the treatment of interdigital tinea pedis. One hundred and fifty-eight patients with tinea pedis clinically and microscopy suggestive of a dermatophyte infection were randomized to receive either placebo, 25% or 50% tea tree oil solution. Patients applied the solution twice daily to affected areas for 4 weeks and were reviewed after 2 and 4 weeks of treatment. There was a marked clinical response seen in 68% of the 50% tea tree oil group and 72% of the 25% tea tree oil group, compared to 39% in the placebo group. Mycological cure was assessed by culture of skin scrapings taken at baseline and after 4 weeks of treatment. The mycological cure rate was 64% in the 50% tea tree oil group, compared to 31% in the placebo group. Four (3.8%) patients applying tea tree oil developed moderate to severe dermatitis that improved quickly on stopping the study medication.
Biju, S S; Ahuja, Alka; Khar, Roop K
Tea tree oil, a popular antimicrobial agent is recommended for the treatment of acne vulgaris, a disease of the pilosebaceous unit. Tea tree oil formulations (colloidal bed, microemulsion, multiple emulsion, and liposomal dispersion containing 5% w/w tea tree oil) were applied to bovine udder skin. The follicular uptake of tea tree oil upon application was determined by a cyanoacrylate method. Tea tree oil was determined by quantifying terpinen-4-ol content using high-performance thin layer chromatography. The accumulation of tea tree oil in the follicular casts was 0.43 +/- 0.01, 0.41 +/- 0.009, 0.21 +/- 0.006, and 0.16 +/- 0.005 percentage by weight (milligram oil/gram of sebum plug) for microemulsion, liposomal dispersion, multiple emulsion, and colloidal bed, respectively. This is the first study of its kind to quantify tea tree oil concentration in the follicles.
Ziółkowska-Klinkosz, Marta; Kedzia, Anna; Meissner, Hhenry O; Kedzia, Andrzej W
The study of the sensitivity to tea tree oil (Australian Company TTD International Pty. Ltd. Sydney) was carried out on 193 strains of anaerobic bacteria isolated from patients with various infections within the oral cavity and respiratory tracts. The susceptibility (MIC) of anaerobes was determined by means of plate dilution technique in Brucella agar supplemented with 5% defibrinated sheep blood, menadione and hemin. Inoculum contained 10(5) CFU per spot was cultured with Steers replicator upon the surface of agar with various tea tree oil concentrations or without oil (anaerobes growth control). Incubation the plates was performed in anaerobic jars under anaerobic conditions at 37 degrees C for 48 h. MIC was defined as the lowest concentrations of the essential oil completely inhibiting growth of anaerobic bacteria. Test results indicate, that among Gram-negative bacteria the most sensitive to essential oil were strains of Veillonella and Porphyromonas species. Essential oil in low concentrations (MIC in the range of = 0.12 - 0.5 mg/mL) inhibited growth of accordingly 80% and 68% strains. The least sensitive were strains of the genus Tannerella, Parabacteroides and Dialister (MIC 1.0 - 2.0 mg/mL). In the case of Gram-positive anaerobic bacteria the tea tree oil was the most active to strains of cocci of the genus Anaerococcus and Ruminococcus (MIC in range = 0.12 - 0.5 mg/mL) or strains of rods of the genus Eubacterium and Eggerthella (MIC = 0.25 mg/mL). Among Gram-positive rods the least sensitive were the strains of the genus Bifidobacterium ( MIC = 2.0 mg/mL). The tea tree oil was more active to Gram-positive than to Gram-negative anaerobic bacteria.
Lou, Weiping; Sun, Shanlei; Wu, Lihong; Sun, Ke
Based on phenological and economic output models established and meteorological data from 1972 to 2013, changes in the phenology, frost risk, and economic output of the Longjing-43 tea tree in the Yuezhou Longjing tea production area of China were evaluated. As the local climate has changed, the beginning dates of tea bud and leaf plucking of this cultivar in all five counties studied has advanced significantly by -1.28 to -0.88 days/decade, with no significant change in the risk of frost. The main tea-producing stages in the tea production cycle include the plucking periods for superfine, grade 1, and grade 2 buds and leaves. Among the five bud and leaf grades, the economic output of the plucking periods for superfine and grade 1 decreased significantly, that for grade 2 showed no significant change, and those for grades 3 and 4 increased significantly. The economic output of large-area tea plantations employing an average of 45 workers per hectare and producing superfine to grade 2 buds and leaves were significantly reduced by 6,745-8,829 yuan/decade/ha, depending on the county. Those tea farmers who planted tea trees on their own small land holdings and produced superfine to grade 4 tea buds and leaves themselves experienced no significant decline in economic output.
Kunicka-Styczyńska, A; Sikora, M; Kalemba, D
The aim of this study was to evaluate the antimicrobial activity of commercial essential oils: lavender, tea tree and lemon, antimicrobials in washing liquid and O/W soft body balm. The inhibition efficacy of essential oils in washing liquid (1% alone or in mixtures), in soft body balm (0.5% alone), as well as combined with the synthetic preservative DMDM hydantoin and 3-iodo-2-propynyl butyl carbamate mixture (0.1 and 0.3%), was tested against S. aureus ATCC 6538, P. aeruginosa ATCC 9027, Candida sp. ŁOCK 0008 and A. niger ATCC 16404 in compliance with the European Pharmacopoeia standards. The components of the system preserving soft body balm were supplemented with a solubilizer. Washing liquids containing only essential oils met Criterion A E.P. only for S. aureus, Candida sp. and A. niger. In soft body balm formulations, oils at a concentration of 0.5% did not reveal any preserving activity. The introduction of a solubilizer to a system containing 0.5% tea tree oil led to a substantial increase in the bacteriostatic activity of the formulation, but did not significantly affect its fungistatic properties. A combination of 0.5% tea tree oil, 5% solubilizer and 0.3% synthetic preservative ensured the microbiological stability of soft body balm in accordance with Criterion A E.P.
Faoagali, J; George, N; Leditschke, J F
Burnaid is a sorbalene-based cream containing 40 mg/g of tea tree oil and 1 mg/g of triclosan. This investigation was carried out to determine the effect of Burnaid, a commercial tea tree oil preparation, against Enterococcus faecalis (ATCC29212), Staphylococcus aureus (ATCC29213), Escherichia coli (ATCC25922), and Pseudomonas aeruginosa (ATCC27853), with the activity of the base product in the commercial preparation. The organisms were suspended in sterile saline (0.5 McFarland Standard) and inoculated onto horse blood agar (E. faecalis and S. aureus) or Mueller-Hinton agar (E. coli and P. aeruginosa). One hundred microliters of Burnaid unsterilized, Burnaid sterilized and the base product (Tinasolve) were placed in duplicate in wells cut into the agar plates. Sterility and inactivation cultures were also performed on the samples. None of the samples were found to be contaminated with bacteria prior to testing. Only S. aureus and E. coli showed zones of growth inhibition around the Burnaid and Tinasolve. Zones of growth inhibition (22 mm) were similar for the active product (Burnaid) and the base (Tinasolve). There was no activity against E. faecalis or P. aeruginosa. In view of our findings and literature indicating the cytotoxicity of tea tree oil against human fibroblasts and epithelial cells, it is recommended that this product should not be used on burn wounds.
Suppression of inflammatory reactions by terpinen-4-ol, a main constituent of tea tree oil, in a murine model of oral candidiasis and its suppressive activity to cytokine production of macrophages in vitro.
Ninomiya, Kentaro; Hayama, Kazumi; Ishijima, Sanae A; Maruyama, Naho; Irie, Hiroshi; Kurihara, Junichi; Abe, Shigeru
The onset of oral candidiasis is accompanied by inflammatory symptoms such as pain in the tongue, edema or tissue damage and lowers the quality of life (QOL) of the patient. In a murine oral candidiasis model, the effects were studied of terpinen-4-ol (T-4-ol), one of the main constituents of tea tree oil, Melaleuca alternifolia, on inflammatory reactions. When immunosuppressed mice were orally infected with Candida albicans, their tongues showed inflammatory symptoms within 24 h after the infection, which was monitored by an increase of myeloperoxidase activity and macrophage inflammatory protein-2 in their tongue homogenates. Oral treatment with 50 µL of 40 mg/mL terpinen-4-ol 3h after the Candida infection clearly suppressed the increase of these inflammatory parameters. In vitro analysis of the effects of terpinen-4-ol on cytokine secretion of macrophages indicated that 800 µg/mL of this substance significantly inhibited the cytokine production of the macrophages cultured in the presence of heat-killed C. albicans cells. Based on these findings, the role of the anti-inflammatory action of T-4-ol in its therapeutic activity against oral candidiasis was discussed.
Pachava, Koteswara Rao; Nadendla, Lakshmi Kavitha; Alluri, Leela Subhashini Choudary; Tahseen, Huma; Sajja, Navya Poojitha
Adherence and colonization of candida on denture soft liners is the most important contributing factor in development of denture stomatitis. This invitro study is undertaken to investigate whether the incorporation of tea tree oil into denture soft liners would inhibit the growth of candida albicans. Each 10 specimen disks incorporated with tea tree oil into soft liners (St) and without tea tree oil (S) were prepared. Both the tea tree oil daily. These disks were inoculated with candida albicans suspension for assessment of fungal growth and were rinsed with sterile water to remove loosely attached surface organisms. The attached yeasts were measured by inoculating them on saboraud's agar. Treated and control disks were stored in distilled water for 1, 30, 60 days and washed daily with wet cotton. Data between treated and control disks were compared by applying t-test. The mean colony forming units (CFU) per mm(2) for specimens without tea tree oil after water storage and wash with wet cotton for 1, 30 and 60 days was 7.1 × 10(6), 6.5 × 10(6), 6.8 × 10(6), respectively and for specimens with tea tree oil CFU decreased significantly to 2.1 × 10(6), 2.8 × 10(6), 3.1 × 10(6) after 1, 30 and 60 days. Treated disks were effective in controlling the growth of C.albicans for two months following water storage. Addition of tea tree oil to denture soft liner significantly reduced growth of C.albicans suggesting a new form of intra oral effective antifungal management for denture stomatitis.
Raut, Chetan Purushottam; Sethi, Kunal S.
Background: Conventional nonsurgical periodontal therapy has been proven to be an effective treatment for patients with chronic periodontitis. Coenzyme Q10 and tea tree oil (TTO) are known to have potential therapeutic benefits in chronic periodontitis. Aims: The aim of the study is to compare the efficacy of Coenzyme Q10 (Perio Q®) and tea tree oil (Melaleuca alternifolia) gel as an adjunct to scaling and root planing in the treatment of chronic periodontitis. Materials and Methods: Patients were divided equally into three groups: Group I (Control group): those receiving placebo gel + SRP, Group II (Test group I): those receiving Perio QTM gel + SRP, and Group III (Test group II): those receiving tea tree oil gel + SRP. A total of 15 patients with 45 sites were enrolled in the study. Clinical parameters evaluated were plaque index (PI), gingival bleeding index (GI), probing pocket depth (PPD), and clinical attachment level (CAL). Statistical Analysis Used: Paired t-test was applied using SPSS software. Results: Mean PPD reduction for Group I, Group II, and Group III was 0.50 ± 0.2, 2.95 ± 0.20, and 2.09 ± 0.15, respectively. Mean CAL reduction for Group I, Group II, and Group III was 0.45 ± 0.22, 2.33 ± 0.04, and 2.28 ± 0.09, respectively. Changes in mean PI scores for Group I, Group II, and Group III were 0.67 ± 017, 1.00 ± 0.11, and 1.08 ± 0.05 and GBI scores were 0.92 ± 0.29, 1.08 ± 0.13, and 0.88 ± 0.28, respectively. Conclusions: Coenzyme Q10 and tea tree oil gel proved to be effective in the treatment of chronic periodontitis. PMID:27630504
Monteiro, Danieli Urach; Azevedo, Maria Isabel; Weiblen, Carla; DE Avila Botton, Sônia; Funk, Nadine Lysyk; DE Bona DA Silva, Cristiane; Zanette, Régis Adriel; Schwanz, Thiago Guilherme; DE LA Rue, Mário Luiz
Cystic echinococcosis is a zoonotic disease of difficult diagnosis and treatment. The use of protoscolicidal agents in procedures is of utmost importance for treatment success. This study was aimed at analysing the in vitro and ex vivo activity of Melaleuca alternifolia oil (tea tree oil - TTO), its nanoemulsion formulation (NE-TTO) and its major component (terpinen-4-ol) against Echinococcus ortleppi protoscoleces obtained from cattle. Concentrations of 2·5, 5 and 10 mg mL-1 of TTO, 10 mg mL-1 of NE-TTO and 1, 1·5 and 2 mg mL-1 of terpinen-4-ol were evaluated in vitro against protoscoleces at 5, 10, 15 and 30 min. TTO was also injected directly into hydatid cysts (ex vivo analysis, n = 20) and the viability of protoscoleces was evaluated at 5, 15 and 30 min. The results indicated protoscolicidal effect at all tested formulations and concentrations. Terpinen-4-ol (2 mg mL-1) activity was superior when compared with the highest concentration of TTO. NE-TTO reached a gradual protoscolicidal effect. TTO at 20 mg mL-1 showed 90% protoscolicidal action in hydatid cysts at 5 min. The results showed that TTO affects the viability of E. ortleppi protoscoleces, suggesting a new protoscolicidal option to the treatment of cystic equinococcosis.
LaPlante, Kerry L
Colonization of methicillin-resistant Staphylococcus aureus (MRSA) commonly leads to infection by the same strain. We examined the activity of lysostaphin, mupirocin, and tea tree oil against clinical MRSA (n = 98) isolates. MIC(50) (range) were as follows: lysostaphin, 0.125 mg/L (0.125-0.25); mupirocin, 0.5 mg/L (0.19-1024); tea tree oil, 1024 mg/L (512-2048). High- and low-level mupirocin resistance was noted in 9.2% of our MRSA isolates. Time kill results indicate MRSA activity at 24 h was lysostaphin = gentamicin = vancomycin (P
Rajkowska, Katarzyna; Kunicka-Styczyńska, Alina; Maroszyńska, Marta; Dąbrowska, Mariola
Members of Candida species cause significant problems in medicine and in many industrial branches also. In order to prevent from Candida sp. development, essential oils are more and more frequently applied as natural, non-toxic, non-pollutive and biodegradable agents with a broad spectrum of antimicrobial activity. The aim of the research was to determine changes in morphology and metabolic properties of Candida albicans in the presence of thyme and tea tree oils. Changes of enzymatic activity of isolates were observed in the presence of both tested essential oils, and they were primarily associated with loss or decrease of activity of all enzymes detected for control. Furthermore, only for 3 out of 11 isolates additional activity of N-acetyl-β-glucosaminidase, α-mannosidase, α-fucosidase and trypsin was detected. Vivid changes in biochemical profiles were found after treatment with tea tree oil and they were related to loss of ability to assimilate D-xylose, D-sorbitol and D-trehalose. The main differences in morphology of isolates compared to the control strain concerned formation of pseudohyphae structures. Both examined essential oils caused changes in cell and colony morphology, as well as in the metabolism of Candida albicans. However, the extent of differences depends on the type and concentration of an essential oil. The most important finding is the broad spectrum of changes in yeast enzymatic profiles induced by thyme and tea tree oils. It can be supposed that these changes, together with loss of ability to assimilate saccharides could significantly impact Candida albicans pathogenicity.
Diabetic foot wounds represent a class of chronic non-healing wounds that can lead to the development of soft tissue infections and osteomyelitis. We reviewed the case of a 44-year-old female with a diabetic foot wound who developed gas gangrene while treating her wound with tea tree oil, a naturally derived antibiotic agent. This case report includes images that represent clinical examination and x-ray findings of a patient who required broad-spectrum antibiotics and emergent surgical consultation. Emergency Department (ED) detection of these complications may prevent loss of life or limb in these patients. PMID:21559069
Hada, Toshiko; Inoue, Yoshihiro; Shiraishi, Akiko; Hamashima, Hajime
The leakage of K(+) ions from Staphylococcus aureus in response to tea tree oil (TTO) was investigated with an ion-selective electrode. The amount of leaked K(+) ions and the rate of leakage of K(+) ions induced by TTO were dependent on the concentration of TTO. Measurements of initial rates required less time than measurements of total amounts and provided an index of the interaction between TTO and the cell membrane. Thus, the initial rate of leakage might be a more useful measure of the antibacterial activity of TTO than the total amount.
Li, He; Zhou, Guo-Ying; Liu, Jun-Ang; Xu, Jianping
The filamentous fungus Colletotrichum fructicola is found in all five continents and is capable of causing severe diseases in a number of economically important plants such as avocado, fig, cocoa, pear, and tea-oil trees. However, almost nothing is known about its patterns of genetic variation and epidemiology on any of its host plant species. Here we analyzed 167 isolates of C. fructicola obtained from the leaves of tea-oil tree Camellia oleifera at 15 plantations in seven Chinese provinces. Multilocus sequence typing was conducted for all isolates based on DNA sequences at fragments of four genes: the internal transcribed spacers of the nuclear ribosomal RNA gene cluster (539 bp), calmodulin (633 bp), glutamine synthetase (711 bp), and glyceraldehyde-3-phosphate dehydrogenase (190 bp), yielding 3.52%, 0.63%, 8.44%, and 7.89% of single nucleotide polymorphic sites and resulting in 15, 5, 12 and 11 alleles respectively at the four gene fragments in the total sample. The combined allelic information from all four loci identified 53 multilocus genotypes with the most frequent represented by 21 isolates distributed in eight tea-oil plantations in three provinces, consistent with long-distance clonal dispersal. However, despite evidence for clonal dispersal, statistically significant genetic differentiation among geographic populations was detected. In addition, while no evidence of recombination was found within any of the four gene fragments, signatures of recombination were found among the four gene fragments in most geographic populations, consistent with sexual mating of this species in nature. Our study provides the first insights into the population genetics and epidemiology of the important plant fungal pathogen C. fructicola. PMID:27299731
Li, He; Zhou, Guo-Ying; Liu, Jun-Ang; Xu, Jianping
The filamentous fungus Colletotrichum fructicola is found in all five continents and is capable of causing severe diseases in a number of economically important plants such as avocado, fig, cocoa, pear, and tea-oil trees. However, almost nothing is known about its patterns of genetic variation and epidemiology on any of its host plant species. Here we analyzed 167 isolates of C. fructicola obtained from the leaves of tea-oil tree Camellia oleifera at 15 plantations in seven Chinese provinces. Multilocus sequence typing was conducted for all isolates based on DNA sequences at fragments of four genes: the internal transcribed spacers of the nuclear ribosomal RNA gene cluster (539 bp), calmodulin (633 bp), glutamine synthetase (711 bp), and glyceraldehyde-3-phosphate dehydrogenase (190 bp), yielding 3.52%, 0.63%, 8.44%, and 7.89% of single nucleotide polymorphic sites and resulting in 15, 5, 12 and 11 alleles respectively at the four gene fragments in the total sample. The combined allelic information from all four loci identified 53 multilocus genotypes with the most frequent represented by 21 isolates distributed in eight tea-oil plantations in three provinces, consistent with long-distance clonal dispersal. However, despite evidence for clonal dispersal, statistically significant genetic differentiation among geographic populations was detected. In addition, while no evidence of recombination was found within any of the four gene fragments, signatures of recombination were found among the four gene fragments in most geographic populations, consistent with sexual mating of this species in nature. Our study provides the first insights into the population genetics and epidemiology of the important plant fungal pathogen C. fructicola.
Fitzi, J; Fürst-Jucker, J; Wegener, T; Saller, R; Reichling, J
Localised dermatitis, for example unspecific eczema or skinfold pyoderma, is a very common diagnosis in dogs. Typical and impressive complaints are pruritus, erythema, erosion and oozing surface. With respect to the underlying disease dermatological treatment is indicated, usually based on antimicrobial and antipruriginous active substances, it can include transient glucocorticoids. An effective and safe alternative might be a phytotherapeutic topical preparation containing tea tree oil. Tea tree oil exerts both antimicrobial and antipruriginous effects. In an open multicenter study efficacy and safety of a standardized 10% tea tree oil cream applied thinly and twice daily for 4 weeks was tested in 53 dogs with chronic dermatitis, particularly non-specific eczema, allergic dermatitis, interdigital pyoderma, acral lick dermatitis and skinfold pyoderma. Analysis of efficacy assessed by investigating veterinarians showed a good or very good response to treatment for 82% of the dogs, significant at a 5% level (p = 0.05). At the end of the study a strong and significant reduction (p = 0.001) as well as disappearance of major symptoms were observed. Only two adverse events (local reactions) possibly related to tea tree oil occurred during therapy. Consequently the tested study medication (Bogaskin) can be considered an alternative for uncomplicated and localised dermatitis in dogs. Bogaskin might allow reduction of other pharmaceutical products, perhaps even replace standard therapy.
Santesteban Muruzábal, R; Hervella Garcés, M; Larrea García, M; Loidi Pascual, L; Agulló Pérez, A; Yanguas Bayona, I
Tea tree oil is an essential oil, whose use is increasing in our setting, due both to its supposed medicinal effects and to its aromatic properties. We describe our experience with allergic contact dermatitis following the application of this oil. Five patients in the last 5 years (0.4% of all the patients studied in specialized consultation) reacted to a 5% concentration of tea tree oil in Vaseline. All the patients presented strong reactions, and in all cases these were considered relevant. Three of them also reacted to oxidized d-limonene, one of the components of tea tree oil, which is present in our standard series. Different cases have been described in the literature on allergic contact dermatitis due to tea tree oil, but until recently it was infrequent in our setting. With the increased popularity of alternative and natural therapies we have witnessed several cases of sensitization to this essential oil, which had been used to treat several supposedly "infectious" skin diseases, but which were very probably different forms of dermatitis.
Sciarrone, Danilo; Ragonese, Carla; Carnovale, Caterina; Piperno, Anna; Dugo, Paola; Dugo, Giovanni; Mondello, Luigi
The natural-like assessment of essential oils is a demanding task due to the growing trend toward adulterations. Usually chiral chromatography was used for this purpose due to the capability of assessing stereospecificity which is directly related to the enzymatic pathways of each plant species. On the other hand, the quality of an essential oil involves also the evaluation of its oxidative state, mainly connected with the age and storage conditions. In fact, some modifications in the chemical profile of the oil can occur if not properly preserved. Alterations of the components due to oxidative reactions lead to the formation of peroxides, endoperoxides and epoxides, such as ascaridole and 1,2,4-trihydroxymenthane, usually present in very low amount, formed by the oxidation of terpinen-4-ol and α-terpinene, respectively. Therefore, in the present research, the quality of Australian Tea Tree oil (Melaleuca alternifolia (Maiden & Betche) Cheel, Myrtaceae) was investigated by means of a multi heart-cut multidimensional gas chromatographic system coupled to a mass spectrometer detector and by conventional enantio-GC. The MDGC system allowed the complete separation of the compounds of interest transferred from the first column to a second dimension based on a different separation mechanism. The MS detector at the end of the second column provided the identification of the peaks with high similarity values because of their high purities after the multidimensional separation. Method validation was carried out, in order to use this procedure for routine application, monitoring the repeatability of 1D retention times and 2D peak areas, LoD and LoQ. Finally, enantiomeric ratios for chiral compounds were established to support quality data obtained.
Li, Yonghua; Shao, Xingfeng; Xu, Jiayu; Wei, Yingying; Xu, Feng; Wang, Hongfei
In order to investigate the effects of tea tree oil (TTO) on mitochondrial morphology and function in Botrytis cinerea, mycelia were treated with TTO at different concentrations. TTO at 2ml/l severely damaged mitochondria, resulting in matrix loss and increased mitochondrial irregularity. Mitochondrial membrane permeability was increased by TTO, as evidenced by a decrease in intracellular adenosine triphosphate (ATP) content and an increase in extracellular ATP content. Increasing concentrations of TTO decreased the activities of enzymes related to mitochondrial function and the tricarboxylic acid (TCA) cycle, affecting malic dehydrogenase, succinate dehydrogenase, ATPase, citrate synthetase, isocitrate dehydrogenase and α-ketoglutarate dehydrogenase, while sharply increasing the level of reactive oxygen species (ROS). These results suggest that mitochondrial damage, resulting in the disruption of the TCA cycle and accumulation of ROS, is involved in the mechanism of TTO antifungal activity against B. cinerea. Copyright © 2017 Elsevier Ltd. All rights reserved.
Davies, Noel W; Larkman, Tony; Marriott, Philip J; Khan, Ikhlas A
A number of papers have appeared in recent years proposing the use of enantiomeric ratios of key monoterpenes in Australian tea tree oil (TTO) for detection of adulterated oils. There are however a range of reported values, even from exactly the same suite of authentic oils, and we address here probable reasons for these differences and stress the importance of establishing reference ratios within each laboratory based on oils of known provenance. Any biological variation in the ratio for the key terpene terpinen-4-ol has been demonstrated to be effectively unmeasurable, because the standard deviation on multiple measurements of the same oil is of the same order as that of multiple authentic oils.
Koo, Hyun; Kim, Tae Hyung; Kim, Kyoung Woo; Wee, Sung Wook; Chun, Yeoun Sook
The purpose of this study was to evaluate the relation between ocular discomfort and ocular Demodex infestation, and therapeutic effects of tea tree oil (TTO) in Demodex blepharitis patients. Three hundred and thirty-five patients with ocular discomfort were evaluated for ocular Demodex infestation and subjective symptoms with ocular surface discomfort index (OSDI) score. Among them, Demodex-infested patients were randomized to receive either eyelid scrubbing with TTO (TTO group,106 patients) or without TTO (Control group, 54 patients) for 1 month. Demodex were found in 84% of patients with ocular discomfort. The number of Demodex was significantly correlated with age (P = 0.04) and OSDI score (P = 0.024). After eyelid scrub treatment, Demodex count was reduced from 4.0 ± 2.5 to 3.2 ± 2.3 in the TTO group (P = 0.004) and from 4.3 ± 2.7 to 4.2 ± 2.5 in the control group (P = 0.27). Also, OSDI score was reduced from 34.5 ± 10.7 to 24.1 ± 11.9 in the TTO group (P = 0.001) and from 35.3 ± 11.6 to 27.5 ± 12.8 in the control group (P = 0.04). In conclusion, Demodex number showed a significant positive correlation with age and subjective ocular discomfort. The tea tree oil eyelid scrub treatment is effective for eliminating ocular Demodex and improving subjective ocular symptoms. PMID:23255861
Kunicka-Styczyńska, A; Sikora, M; Kalemba, D
The aim of the study was to verify the antimicrobial activity of commercial essential oils: lavender, tea tree and lemon as the components of a preservative system in oil in water body milks. The inhibition efficacy of essential oils alone (0.5%), in mixtures (1%) as well as combined with the synthetic preservative 1,3-dimethylol-5,5-dimethylhydantoin and a 3-iodo-2-propynyl butyl carbamate mixture (0.1% and 0.2%) was tested against Staphylococcus aureus ATCC 6538, Pseudomonas aeruginosa ATCC 9027, Candida sp. ŁOCK 0008 and Aspergillus niger ATCC 16404 in compliance with the standards of the European Pharmacopoeia Commission. The in vitro activity of oils determined by an impedimetric method was also compared with their activity in cosmetic preparations. Criterion A for bacteria (reduction in the inoculum by 3 logarithmic units within 7 days with no increase up to the 28th day) and fungi (reduction in the inoculum by 2 logarithmic units within 14 days with no increase up to the 28th day) was fulfilled for cosmetic formulations containing the tested essential oils with 0.2% of the synthetic preservative. The preservative concentration could be decreased to 0.1% (with preserving the same efficacy) in combination with lavender and tea tree oils at a concentration of 0.5% each. In all combinations of essential oils with the synthetic preservative, a synergistic effect of the preservative system components was observed, which made it possible to reduce the usable level of the synthetic preservative up to 8.5 times. To develop an effective preservative system in cosmetics in which a synthetic chemical preservative is replaced by natural essential oils.
Koo, Hyun; Kim, Tae Hyung; Kim, Kyoung Woo; Wee, Sung Wook; Chun, Yeoun Sook; Kim, Jae Chan
The purpose of this study was to evaluate the relation between ocular discomfort and ocular Demodex infestation, and therapeutic effects of tea tree oil (TTO) in Demodex blepharitis patients. Three hundred and thirty-five patients with ocular discomfort were evaluated for ocular Demodex infestation and subjective symptoms with ocular surface discomfort index (OSDI) score. Among them, Demodex-infested patients were randomized to receive either eyelid scrubbing with TTO (TTO group,106 patients) or without TTO (Control group, 54 patients) for 1 month. Demodex were found in 84% of patients with ocular discomfort. The number of Demodex was significantly correlated with age (P = 0.04) and OSDI score (P = 0.024). After eyelid scrub treatment, Demodex count was reduced from 4.0 ± 2.5 to 3.2 ± 2.3 in the TTO group (P = 0.004) and from 4.3 ± 2.7 to 4.2 ± 2.5 in the control group (P = 0.27). Also, OSDI score was reduced from 34.5 ± 10.7 to 24.1 ± 11.9 in the TTO group (P = 0.001) and from 35.3 ± 11.6 to 27.5 ± 12.8 in the control group (P = 0.04). In conclusion, Demodex number showed a significant positive correlation with age and subjective ocular discomfort. The tea tree oil eyelid scrub treatment is effective for eliminating ocular Demodex and improving subjective ocular symptoms.
Shao, X; Cheng, S; Wang, H; Yu, D; Mungai, C
Tea tree oil (TTO) has been confirmed in previous study as a potential natural antifungal agent to control Botrytis cinerea and grey mould in fresh fruit. However, the mechanism of its action has not been clearly revealed, and some hypotheses mainly depended on the results obtained from the bacterial test. For the antifungal mechanism, the effect of TTO on the mycelium morphology and ultrastructure, cell wall and membrane, and membrane fatty acid composition of B. cinerea was investigated in vitro experiments. Tea tree oil in vapour or contact phase exhibited higher activity against the mycelial growth of B. cinerea. Observations using scanning electron microscope and transmission electron microscope revealed that the mycelial morphology and ultrastructure alternations caused by TTO are the markedly shriveled or flatted empty hyphae, with thick cell walls, ruptured plasmalemma and cytoplasmic coagulation or leakage. Furthermore, TTO caused significantly higher alkaline phosphatase activity after 4-h treatment and markedly higher absorbance at 260 nm and electric conductivity in the external hyphae of fungi after 16-h treatment. Moreover, decreased unsaturated/saturated fatty acid ratio of the fungal membrane was also observed after TTO treatment. The methodology used in this study confirmed that the cell wall destroyed firstly in the presence of TTO, and then the membrane fatty acid composition changed, which resulted in the increasing of membrane permeability and releasing of cellular material. The above findings may be the main reason for TTO's antifungal ability to B. cinerea. Understanding the mechanism of TTO antifungal action to B. cinerea is helpful for its commercial application on the preservation of fresh fruit and vegetables. © 2013 The Society for Applied Microbiology.
Bustos-Segura, Carlos; Külheim, Carsten; Foley, William
Plant chemical polymorphisms, or plant chemotypes, are characterized by intraspecific discrete differences of plant secondary metabolites in the same plant tissue. Chemotypes that differ in foliar terpene composition are found commonly in Myrtaceae. In this study, we focused on terpene chemotypes of medicinal tea tree, Melalecua alternifolia, to explore whether this variation affects two specialist herbivores Paropsisterna tigrina and Faex sp. (Coleoptera: Chrysomelidae), and if this could explain the maintenance of this variation. We tested whether insect performance, oviposition preference, and plant damage were associated with different chemotypes. We found that larval growth rate of Faex sp. was higher in chemotypes with high concentrations of 1,8-cineole, and that oviposition preference depended on the chemotype of the larval diet. Although performance traits and preference for oviposition of P. tigrina did not vary among chemotypes, adults inflicted less damage on plants with a high concentration of terpinolene. Additionally, we tested whether different chemotypes showed different levels of susceptibility by myrtle rust (Puccinia psidii). We found that plants with a high concentration of 1,8-cineole were more likely to be infected under controlled conditions. Although there is evidence that terpene chemotypes are a mediator of the interaction with natural enemies, the most detrimental pest of this plant, P. tigrina, does not seem to be affected by variation in plant terpenes.
Tea oil tree (Camellia oleifera, Co) provides a fine edible oil source in China. Tea oil from the seeds is very beneficial to human health. Fructose-1,6-bisphosphate aldolase (FBA) hydrolyzes fructose-1,6-bisphosphate into dihydroxyacetone phosphate and glyceraldehyde 3-phosphate, two critical metab...
Forrer, Marcel; Kulik, Eva M; Filippi, Andreas; Waltimo, Tuomas
To investigate the antimicrobial effect of alpha-bisabolol and tea tree oil alone and in combination against the halitosis-associated Gram-positive bacillus Solobacterium moorei. The inhibitory activity of alpha-bisabolol and tea tree oil against the reference strain S. moorei CCUG39336 and four clinical S. moorei isolates was investigated by a direct exposure test. Additionally, the ability of alpha-bisabolol to increase the sensitivity of S. moorei was tested by pretreating the bacteria with sublethal concentrations prior to the administration of tea tree oil. A dose-dependent killing was observed for the antimicrobial agents in a direct exposure test with the reference strain S. moorei CCUG39336. Concentrations of ≥0.5% tea tree oil caused decreases in viability of >5 log colony forming units/ml even after short incubation periods, while bacterial viability was less affected by alpha-bisabolol. The combination of 0.1% alpha-bisabolol plus 0.05% tea tree oil showed a synergistic effect on S. moorei strain CCUG39336 and on two of the four clinical S. moorei isolates tested. However, incubation of S. moorei with a sublethal concentration of 0.1% alpha-bisabolol for three days prior to the administration of 0.05% tea tree oil did not enhance the antibacterial effect of tea tree oil. Halitosis-associated bacterium S. moorei is susceptible to the antimicrobial agents tea tree oil and alpha-bisabolol, suggesting that these compounds might be beneficial in oral healthcare products. Copyright © 2012 Elsevier Ltd. All rights reserved.
Luo, Fan; Zhang, Ting; Gong, Xue-jiao; Du, Xiao; Ma, Wei-wei
The variety of the contents of N, P, K and photo-biological characters in a bud and two leaves tea tree new shoots were determined to investigate the effects of different fertilization ways, i.e., single or combined N, P, K fertilizer. The regression equations of net photosynthetic rate (Pn) of tea tree in spring, summer and autumn were set up by stepwise regression analysis. The results showed that fertilization ways significantly affected the contents of N, P, K in new shoot. In the same fertilization ways, the contents of N, P in the new shoot was less in summer and autumn than in spring, but the content of K was in contrast. Combined application of N, P and K fertilizer improved Pn of the tea trees in spring. Single application of P fertilizer inhibited the Pn of the tea trees in summer and autumn, while single application of N fertilizer significantly improved it. In the same fertilization ways, the Pn of the tea trees in summer and autumn was higher than in spring. The stomatal conductance (g(s)) and transpiration rate (T(r)) had positive correlations to P, in summer and autumn. Regression and correlation analysis showed that the physiological factors affecting Pn of the tea trees varied with seasons, and the common factors were the Ci and the content of P. Ci had some subduction to Pn, and it was improved by the content of phosphorus.
Reichling, J; Fitzi, J; Hellmann, K; Wegener, T; Bucher, S; Saller, R
Tea tree oil, a volatile oil, is well known for its broad antibacterial and antifungal activity. A standardised and stabilised 10% tea tree oil cream was tested against a commercial skin care cream (control cream) in the management of canine localised acute and chronic dermatitis. Fifty-seven dogs with clinical manifestations of mostly pruritic skin lesions or alterations, skin fold pyodermas and other forms of dermatitis, corroborated by predominantly positive fungal and bacterial skin isolates, were enrolled by seven practising veterinarians and randomly allocated to two study groups (28:29) and were treated twice daily with a blinded topical preparation. After 10 days of treatment, success rates of 71% for the tea tree oil cream and 41% for the control cream (over-all efficacy documented by the veterinary investigator) differed significantly (p = 0.04), favouring tea tree oil cream treatment. Accordingly on day 10, the tea tree oil cream caused significantly faster relief than the control cream (p = 0.04) for two common clinical dermatitis signs, pruritus (occurring in 84 % of dogs) and alopecia. Only one adverse event was reported in the tea tree oil group (suspected not to be causally related to the study drug) and none in the control cream group. The tested herbal cream appears to be a fast-acting safe alternative to conventional therapy for symptomatic treatment of canine localised dermatitis with pruritus.
Enshaieh, Shahla; Jooya, Abolfazl; Siadat, Amir Hossein; Iraji, Fariba
Finding an effective treatment for acne that is well tolerated by the patients is a challenge. One study has suggested the efficacy of tea tree oil in treatment of the acne vulgaris. To determine the efficacy of tea tree oil in mild to moderate acne vulgaris. This was a randomized double-blind clinical trial performed in 60 patients with mild to moderate acne vulgaris. They were randomly divided into two groups and were treated with tea tree oil gel (n=30) or placebo (n=30). They were followed every 15 days for a period of 45 days. Response to treatment was evaluated by the total acne lesions counting (TLC) and acne severity index (ASI). The data was analyzed statistically using t-test and by SPSS program. There were no significant differences regarding demographic characteristics between the two groups. There was a significant difference between tea tree oil gel and placebo in the improvement of the TLC and also regarding improvement of the ASI. In terms of TLC and ASI, tea tree oil gel was 3.55 times and 5.75 times more effective than placebo respectively. Side-effects with both groups were relatively similar and tolerable. Topical 5% tea tree oil is an effective treatment for mild to moderate acne vulgaris.
Rudbäck, Johanna; Bergström, Moa Andresen; Börje, Anna; Nilsson, Ulrika; Karlberg, Ann-Therese
The monoterpene α-terpinene is used as a fragrance compound and is present in different essential oils. It is one of the components responsible for the antioxidant activity of tea tree oil. α-Terpinene is structurally similar to other monoterpenes, e.g., limonene, known to autoxidize on air exposure and form allergenic compounds. The aim of the present study was to investigate the possible autoxidation of α-terpinene at room temperature. To investigate the sensitization potency of air-exposed α-terpinene and the oxidation products formed, the murine local lymph node assay was used. Chemical analysis showed that α-terpinene degrades rapidly, forming allylic epoxides and p-cymene as the major oxidation products and also hydrogen peroxide. Thus, the oxidation pathway differs compared to that of, e.g., limonene, which forms highly allergenic hydroperoxides as the primary oxidation products on autoxidation. The sensitization potency of α-terpinene was increased after air-exposure. The allylic epoxides and a fraction, in which only an α,β-unsaturated aldehyde could be identified, were shown to be strong sensitizers in the local lymph node assay. Thus, we consider them to be the major contributors to the increased sensitization potency of the autoxidized mixture. We also investigated the presence of α-terpinene and its oxidation products in four different tea tree oil samples of various ages. α-Terpinene and its oxidation products were identified in all of the tea tree oil samples. Thus, from a technical perspective, α-terpinene is a true antioxidant since it autoxidizes rapidly compared with many other compounds, preventing these from degradation. However, as it easily autoxidizes to form allergens, its suitability can be questioned when used in products for topical applications, e.g., in tea tree oil but also in cosmetics and skin care products.
Söderberg, T A; Johansson, A; Gref, R
The present study was undertaken to assess and compare the in vitro cytotoxic effects of three resin acid analogues: dehydrobietic acid, podocarpic acid, O-methylpodocarpic acid; an essential oil from Australia (tea tree oil); and tapped oleoresin from Thailand, on human epithelial and fibroblast cells, using a quantitative neutral red spectrophotometric assay. All of the investigated compounds except for tea tree oil exhibited a cytotoxic activity which was proportional to their concentrations and time of exposure up to 24 h, i.e. higher concentrations and longer time of exposure caused increased cell death. Dehydroabietic acid and the oleoresin were the most toxic compounds followed by O-methylpodocarpic acid, whereas podocarpic acid and tea tree oil showed a lower level of toxicity. On the basis on these findings it is concluded that an isopropyl group on the aromatic C-ring is of great importance for the cytotoxicity of the tested abietane resin acids, thus indicating that the cytotoxic activity of oleoresins most probably is caused by synergistic or additive effects of resin acids. The results from this work support the view that antibacterial activity parallels cytotoxic activity which suggests a similar mode of action, most probably exerted by membrane-associated reactions.
Flores, Fernanda C; De Lima, Julia A; Da Silva, Cássia R; Benvegnú, Dalila; Ferreira, Juliano; Burger, Marilise E; Beck, Ruy C R; Rolim, Clarice M B; Rocha, Maria Isabel U M; Da Veiga, Marcelo L; Da Silva, Cristiane de B
In previous works, we developed nanocapsules and nanoemulsions containing the tea tree oil. The aim of this work was to prepare and characterize hydrogels containing these nanocarriers, and to evaluate their in vivo efficacy in protecting skin damage induced by UVB and cutaneous wound healing. Hydrogels were prepared using Carbopol Ultrez and their physicochemical characteristics were evaluated: macroscopic analysis, pH, spreadability and rheological properties. The in vivo antiedematogenic effect was evaluated by ear thickness measurement after UVB-irradiation. In order to evaluate healing action of hydrogels, we investigated the regression of the cutaneous lesion in rats. Hydrogels showed homogeneous aspect and pH values between 5.6-5.8 and a non-Newtonian behavior. The presence of nanocapsules and nanoemulsions in hydrogels did not change their spreadability profile. The inclusion of tea tree oil in the nanocapsules and nanoemulsions allowed reducing the edema induced by UVB exposure. Hydrogel containing nanocapsules presented a higher reduction of the wound area compared to the hydrogel containing nanoemulsions and hydrogel containing allantoin. This study shows the feasibility of obtained dermatological formulations containing the tea tree oil associated in nanostructured systems. These formulations represent a promising approach to topical treatment of inflammatory disorders and wound healing.
Li, Miao; Zhu, Lifei; Zhang, Tongtong; Liu, Boming; Du, Lina; Jin, Yiguang
Bacterial pneumonia is a common cause of death worldwide. Tea tree oil (TTO) is a potent antimicrobial natural product, which is formulated in dry powder inhalers (DPIs) for the treatment of fungal and bacterial pneumonia. Tea tree oil-β-cyclodextrin inclusion complexes (TTO-β-CD) were prepared and characterized. Aerodynamic properties of TTO-β-CD powders were measured. The rat models of fungal (Candida albicans) and bacterial (Acinetobacter baumannii) pneumonia were prepared. Saline, TTO, TTO-β-CD and the positive drug (fluconazole or penicillin) were directly delivered to the rat lungs. Pathological and biological assays were conducted. Tea tree oil-β-CD powders had an appropriate aerodynamic diameter of 5.59 μm and the fine particle fraction of 51.22%, suitable for pulmonary delivery. TTO-β-CD showed higher and similar antipneumonic effects on the rat models than fluconazole and penicillin, respectively. The effects of TTO-β-CD were higher than TTO alone. The antipneumonic mechanisms involved blocking the recruitment of leucocytes and neutrophils, eliminating the microbes, downregulating pro-inflammatory cytokines (including tumour necrosis factor-α, interleukin-1β and interleukin-6), suppressing cyclooxygenase 2 expression, and further reducing lung injury. Inhaled TTO-β-CD powders have the advantages of portability, high stability, self-administration, high lung deposition and good antipneumonic effect. It is a promising DPI for the treatment of fungal and bacterial pneumonia. © 2017 Royal Pharmaceutical Society.
Shrestha, Meena; Ho, Thao M; Bhandari, Bhesh R
An innovative method to encapsulate tea tree oil (TTO) by direct complexation with solid amorphous beta-cyclodextrin (β-CD) was investigated. A β-CD to TTO ratio of 90.5:9.5 (104.9mg TTO/g β-CD) was used in all complexation methods. The encapsulation was performed by direct mixing, and direct mixing was followed by the addition of water (13-17% moisture content, MC) or absolute ethanol (1:1, 1:2, 1:3 and 1:4 TTO:ethanol). The direct mixing method complexed the lowest amount of TTO (60.77mg TTO/g β-CD). Powder recrystallized using 17% MC included 99.63mg of TTO/g β-CD. The addition of ethanol at 1:2 and 1:3 TTO:ethanol ratios resulted in the inclusion of 94.3 and 98.45mg of TTO/g β-CD respectively, which was similar to that of TTO encapsulated in the conventional paste method (95.56mg TTO/g β-CD), suggesting an effective solid encapsulation method. The XRD and DSC results indicated that the amorphous TTO-β-CD complex was crystallized by the addition of water and ethanol.
Tranchida, Peter Q; Shellie, Robert A; Purcaro, Giorgia; Conte, Lanfranco S; Dugo, Paola; Dugo, Giovanni; Mondello, Luigi
The present research is focused on the qualitative elucidation of the chemical profile of fresh tea tree essential oil and an oxidized, aged (circa 1984) counterpart by using the most powerful analytical tool available today for volatile analysis, namely comprehensive two-dimensional gas chromatography (GCxGC) in combination with a mass spectrometer (MS). The rapid-scanning quadrupole (q) MS system employed generated a sufficient number of spectra/s (20/s) for the reliable identification of the high-speed GCxGC peaks. The total ion current GCxGC-qMS chromatogram of the fresh product was characterized by the presence of approximately 130 unknowns. Among these, 61 peaks were assigned with spectral similarities > or = 90%, while 28 components presented MS library matches in the 80-89% range. With regards to the oxidized essential oil, about 180 volatiles were visible on the 2D plane with 63 of these characterized by library "hits" > or = 90% and 45 presenting similarities within the 80-89% range. The use of the enhanced-resolution 3D methodology enabled the full separation of the samples analyzed and, hence, a clear distinction between the essential oils.
Khalil, Zeinab; Pearce, Annette L; Satkunanathan, Narmatha; Storer, Emma; Finlay-Jones, John J; Hart, Prue H
When applied 20 min after injection of histamine into human forearm skin, tea tree oil (TTO) reduces the developing cutaneous vascular response. In this study, the effect of TTO on inflammatory microvascular changes was dissected at the base of an experimental blister on rat skin. 1,8-Cineole, representing 2% of TTO, reduced vascular changes induced by sensory neuropeptides released when the distal portion of a cut sciatic nerve was electrically stimulated. The pre-terminal modulatory effect of 1,8-Cineole was confirmed in tests in sensory-denervated rats. Terpinen-4-ol (approximately 40% TTO) reduced substance P-induced microvascular changes and protein extravasation by a direct nitric oxide-mediated effect on the microvasculature, without sensory nerve involvement. alpha-Terpineol (3% of TTO) regulated both pre- and post-sensory nerve terminals. In human skin, terpinen-4-ol applied 10 min after histamine injection, but not alpha-terpineol or 1,8-cineole, regulated the developing wheal and flare suggesting that the histamine-induced responses in humans (at the dose used in this study, 50 microL of 330 microM histamine) are in large part determined by histamine directly affecting the vasculature via post-terminal-mediated events. The underlying strength of these studies is the use of a well-established rat physiologic model to differentiate the mechanism of regulation of microvascular changes by modulatory agents.
Golab, Mateusz; Skwarlo-Sonta, Krystyna
Tea tree oil (TTO) is well known as an antimicrobial and immunomodulatory agent. In the present study we confirmed the anti-inflammatory properties of TTO and investigated the involvement of the hypothalamic-pituitary-adrenal (HPA) axis in the immunomodulatory action of TTO administered by inhalation. Sexually mature, 6-8-week-old, C(57)BI(10) x CBA/H (F(1)) male mice were used. One group of animals was injected intra-peritoneally (ip) with Zymosan to elicit peritoneal inflammation and was then submitted to four sessions of TTO inhalation (15 mins each). Some of the mice were simultaneously injected ip with Antalarmin, a CRH-1 receptor antagonist, to block HPA axis functions. Twenty-four hours after the injections the mice were killed by CO(2) asphyxia, and peritoneal leukocytes (PTLs) were isolated and counted. Levels of reactive oxygen species (ROS) and cyclooxygenase (COX) activity in PTLs were assessed by fluorimetric and colorimetric assays, respectively. The results obtained show that sessions of TTO inhalation exert a strong anti-inflammatory influence on the immune system stimulated by Zymosan injection, while having no influence on PTL number, ROS level, and COX activity in mice without inflammation. The HPA axis was shown to mediate the anti-inflammatory effect of TTO; Antalarmin abolished the influence of inhaled TTO on PTL number and their ROS production in mice with experimental peritonitis, but it had no effect on these parameters in mice without inflammation.
Di Vito, Maura; Mattarelli, Paola; Modesto, Monica; Girolamo, Antonietta; Ballardini, Milva; Tamburro, Annunziata; Meledandri, Marcello; Mondello, Francesca
The aim of this work is to evaluate the in vitro microbicidal activity of vaginal suppositories (VS) containing tea tree oil (TTO-VS) towards Candida spp. and vaginal probiotics. A total of 20 Candida spp. strains, taken from patients with vaginitis and from an established type collection, including reference strains, were analysed by using the CLSI microdilution method. To study the action of VS towards the beneficial vaginal microbiota, the sensitivity of Bifidobacterium animalis subsp. lactis (DSM 10140) and Lactobacillus spp. (Lactobacillus casei R-215 and Lactobacillus acidophilus R-52) was tested. Both TTO-VS and TTO showed fungicidal activity against all strains of Candida spp. whereas placebo-VS or the Aloe gel used as controls were ineffective. The study of fractional fungicidal concentrations (FFC) showed synergistic interaction with the association between Amphotericin B and TTO (0.25 to 0.08 µg/ml, respectively) against Candida albicans. Instead, the probiotics were only affected by TTO concentration ≥ 4% v/v, while, at concentrations < 2% v/v, they remained viable. TTO-VS exhibits, in vitro, a selective fungicidal action, slightly affecting only the Bifidobacteriun animalis strain growth belonging to the vaginal microbiota. In vivo studies are needed to confirm the efficacy to prevent acute or recurrent vaginal candidiasis.
Li, Miao; Zhu, Lifei; Liu, Boming; Du, Lina; Jia, Xiaodong; Han, Li; Jin, Yiguang
Tea tree oil (TTO) is a natural essential oil with strong antimicrobial efficacy and little drug resistance. However, the biomedical applications of TTO are limited due to its hydrophobicity and formulation problems. Here, we prepared an inhalable TTO nanoemulsion (nanoTTO) for local therapies of bacterial and fungal pneumonia. The optimal formulation of nanoTTOs consisted of TTO/Cremophor EL/water with a mean size of 12.5nm. The nanoTTOs showed strong in vitro antimicrobial activities on Escherichia coli, Acinetobacter baumannii, Klebsiella pneumoniae, Staphylococcus aureus and Candida albicans. After inhalation to the lung, the nanoTTOs had higher anti-fungal effect than fluconazole on the fungal pneumonia rat models with reduced lung injury, highly microbial clearance, blocking of leukocyte recruitment, and decrease of pro-inflammatory mediators. In the case of rat bacterial pneumonia, the nanoTTOs showed slightly lower therapeutic efficacy than penicillin though at a much lower dose. Taken together, our results show that the inhalable nanoTTOs are promising nanomedicines for local therapies of fungal and bacterial pneumonia with no obvious adverse events.
Rieder, Bernhard O
Reliable exposure data are essential to evaluate the safety of ingredients in cosmetics. The study reported here was carried out on behalf of the Australian Tea Tree Industry Association in order to support safety assessment of TTO in consumer cosmetic products. Data regarding the use of TTO-containing cosmetic products were collected through a web-survey among 2535 qualified users of validated TTO-containing cosmetics in 5 European countries. Data regarding the percentage of TTO present in the individual products (TTO-inclusion) were collected from the suppliers of those products. Beyond TTO exposure-measures there were several significant findings: One is a special "TTO-effect" for several categories of TTO-containing cosmetic products showing a positive correlation between consumers' strength of TTO-orientation and frequency of product use, combined with a negative correlation between frequency of product use and amount of product used per application. Another is significant differences regarding the intensity of product use between TTO-containing cosmetics and respective types of products in general. Thus it seems not to be appropriate to evaluate the toxicological safety of certain ingredients of cosmetic products from exposure data on "generic" types of cosmetic products. Copyright © 2017 Elsevier Ltd. All rights reserved.
Ge, Yan; Ge, Mingqiao
The aim of this study is to prepare tea tree oil liposome (TTOL) and optimize the preparation condition by single factor experiment and statistical design. TTOL was prepared using a thin-film hydration with the combination of sonication method and the preparation conditions of TTOL were optimized with response surface methodology (RSM). The optimal preparation conditions for TTOL by response surface methodology were as follows: the mass ratio of PC and Cho 5.51, TTO concentration 1.21% (v/v) and Tween 80 concentration 0.79% (v/v). The response surface analysis showed that the significant (p < 0.05) second-order polynomial regression equations successfully fitted for all dependent variables with no significant (p > 0.05) lack of fit for the reduced models. Furthermore, the interaction of the mass ratio of PC/Cho and TTO concentration had a significant effect. The amounts of Tween 80 required were also reduced with RSM. Under these conditions, the experimental encapsulation efficiency of TTOL was 97.81 ± 0.33%, which was close with the predicted value. Therefore, the optimized preparation condition was very reliable. The increased entrapment efficiency would significantly improve the TTO stability and bioavailability.
Cuaron, Jesus A; Dulal, Santosh; Cooke, Peter H; Torres, Nathanial J; Gustafson, John E
Tea tree oil (TTO)-reduced susceptibility (TTORS) mutants of two Staphylococcus aureus laboratory strains were isolated utilizing TTO gradient plates. Attempts to isolate TTORS mutants employing agar plates containing single TTO concentrations failed. All TTORS mutants demonstrated a small colony variant (SCV) phenotype and produced cells with a smaller diameter, as determined by scanning electron microscopy. The addition of SCV auxotrophic supplements to media did not lead to an increase in TTORS mutant colony size. Revertants were also isolated from the TTORS mutants following growth in drug-free media, and all revertant strains demonstrated phenotypes similar to their respective parent strains. Transmission electron microscopy revealed that an SH1000 TTORS mutant demonstrated a thinner cell wall and novel septal invaginations compared with parent strain SH1000. In addition, comparative genomic sequencing did not reveal any mutations in an SH1000 TTORS mutant previously linked to well-characterized SCV genotypes. This study demonstrates that TTO can select for a unique SCV phenotype. Copyright © 2014 John Wiley & Sons, Ltd.
Tighe, Sean; Gao, Ying-Ying; Tseng, Scheffer C. G.
Purpose To determine the active ingredient in tea tree oil (TTO) responsible for its reported killing effect on Demodex mites, the most common ectoparasite found in the human skin extending to the eye. Methods Using a reported in vitro killing assay to measure the survival time of adult Demodex folliculorum up to 150 minutes, we have screened serial concentrations of 13 of the 15 known ingredients of TTO (ISO4730:2004) that were soluble in mineral oil and examined their synergistic relationships in killing mites. The most potent ingredient was then tested for its efficacy in killing Demodex in vivo. Results All ingredients exhibited a dose-dependent killing effect. Besides Terpinen-4-ol, the order of relative potency did not correlate with the order of relative abundance in TTO for the remaining 12 ingredients. Terpinen-4-ol was the most potent ingredient followed by α-Terpineol, 1,8-Cineole and Sabinene. Terpinen-4-ol, the most abundant ingredient in TTO, was more potent than TTO at equivalent concentrations and its killing effect was even observable at a mere concentration of 1%. Terpinen-4-ol exhibited a significant synergistic effect with Terpinolene, but an antagonistic effect with α-Terpineol in killing mites (both P < 0.05). In vivo, Terpinen-4-ol was shown to eradicate mites. Conclusions The above finding suggests that deployment of Terpinen-4-ol alone should enhance its potency in killing Demodex mites by reducing the adverse and antagonistic effects from other ingredients in TTO. Translational Relevance Terpinen-4-ol can be adopted in future formulations of acaricides to treat a number of ocular and cutaneous diseases caused by demodicosis. PMID:24349880
Nielsen, Jesper Bo; Nielsen, Flemming
Tea tree oil (TTO) is a complex mixture of terpene hydrocarbons. Intensive topical use of TTO in different cosmetics and investigations into its potential as an antimicrobial or anti-inflammatory agent has accentuated the need for studies on the toxicity of TTO. We have applied an experimental in vitro model using static diffusion cells with human skin to study penetration characteristics of terpinen-4-ol and the way TTO affects the barrier integrity of the skin and the percutaneous penetration of two chemicals covering a range of solubilities from 0.03 g/l (methiocarb) to 3.0 g/l (benzoic acid). Through GC-MS analysis we identified the major constituents of TTO. In our experimental set-up with full-thickness skin, only the least lipophilic ingredients of TTO penetrated the skin. Barrier integrity was evaluated through measurement of percutaneous penetration of tritiated water. Data indicate that 1% TTO does not affect barrier conditions. The Kp value for tritiated water was increased significantly at 5% TTO, which demonstrate that the barrier integrity is affected at this relatively low concentration of TTO. The barrier integrity is, however, not seriously damaged, but our data indicate an initiated and concentration-dependent effect on the barrier integrity. TTO changed the penetration characteristics for benzoic acid as well as for methiocarb. The general effect was that TTO reduced the maximal flux. For methiocarb, the lag-time was also prolonged by increasing the TTO concentration in the donor phase to 5%. Thus, TTO reduced the overall amount of benzoic acid as well as methiocarb entering the receptor chamber.
Tighe, Sean; Gao, Ying-Ying; Tseng, Scheffer C G
To determine the active ingredient in tea tree oil (TTO) responsible for its reported killing effect on Demodex mites, the most common ectoparasite found in the human skin extending to the eye. Using a reported in vitro killing assay to measure the survival time of adult Demodex folliculorum up to 150 minutes, we have screened serial concentrations of 13 of the 15 known ingredients of TTO (ISO4730:2004) that were soluble in mineral oil and examined their synergistic relationships in killing mites. The most potent ingredient was then tested for its efficacy in killing Demodex in vivo. All ingredients exhibited a dose-dependent killing effect. Besides Terpinen-4-ol, the order of relative potency did not correlate with the order of relative abundance in TTO for the remaining 12 ingredients. Terpinen-4-ol was the most potent ingredient followed by α-Terpineol, 1,8-Cineole and Sabinene. Terpinen-4-ol, the most abundant ingredient in TTO, was more potent than TTO at equivalent concentrations and its killing effect was even observable at a mere concentration of 1%. Terpinen-4-ol exhibited a significant synergistic effect with Terpinolene, but an antagonistic effect with α-Terpineol in killing mites (both P < 0.05). In vivo, Terpinen-4-ol was shown to eradicate mites. The above finding suggests that deployment of Terpinen-4-ol alone should enhance its potency in killing Demodex mites by reducing the adverse and antagonistic effects from other ingredients in TTO. Terpinen-4-ol can be adopted in future formulations of acaricides to treat a number of ocular and cutaneous diseases caused by demodicosis.
Khan, Safdar A; McLean, Mary Kay; Slater, Margaret R
To determine the frequency, types, and severity of clinical signs; geographic distribution; and treatment information associated with toxicosis caused by 100% tea tree oil (TTO) in dogs and cats in the United States and Canada. Retrospective case series. 337 dogs and 106 cats with evidence of exposure to 100% TTO. 10-year incident data were retrieved from the ASPCA Animal Poison Control Center database from January 2002 to December 2012. Only evidenced or witnessed incidents assessed as toxicosis or suspected toxicosis were included. Signalment, amount of TTO used, intention of use, and outcome information were evaluated. Severity of illness and correlations with breed, sex, age, and weight were determined. TTO was intentionally used in 395 of 443 (89%) animals. The amount used ranged from 0.1 to 85 mL. Incidents were reported from 41 states, the District of Columbia, and 4 Canadian provinces. Exposure route was cutaneous in 221 (50%) animals, cutaneous and oral in 133 (30%), and oral in 67 (15%). Clinical signs developed within 2 to 12 hours and lasted up to 72 hours. The most common signs were increased salivation or drooling, signs of CNS depression or lethargy, paresis, ataxia, and tremors. A significant association with severity of illness was found for age and weight, with higher prevalence of major illness in younger and smaller cats. Intentional or accidental use of 100% TTO in dogs or cats caused serious signs of CNS depression, paresis, ataxia, or tremors within hours after exposure and lasting up to 3 days. Younger cats and those with lighter body weight were at greater risk of developing major illness.
Malhi, Harsimran Kaur; Tu, Jenny; Riley, Thomas V; Kumarasinghe, Sujith Prasad; Hammer, Katherine A
The efficacy, tolerability and acceptability of a tea tree oil gel (200 mg/g) and face wash (7 mg/g) were evaluated for the treatment of mild to moderate facial acne. In this open-label, uncontrolled phase II pilot study, participants applied tea tree oil products to the face twice daily for 12 weeks and were assessed after 4, 8 and 12 weeks. Efficacy was determined from total numbers of facial acne lesions and the investigator global assessment (IGA) score. Tolerability was evaluated by the frequency of adverse events and the mean tolerability score determined at each visit. Product acceptability was assessed via a questionnaire at the end of the study period. Altogether 18 participants were enrolled, of whom 14 completed the study. Mean total lesion counts were 23.7 at baseline, 17.2 at 4, 15.1 at 8 and 10.7 at 12 weeks. Total lesion counts differed significantly over time by repeated measures anova (P < 0.0001). The mean IGA score was 2.4 at baseline, 2.2 at 4, 2.0 at 8 and 1.9 at 12 weeks, which also differed significantly over time (P = 0.0094). No serious adverse events occurred and minor local tolerability events were limited to peeling, dryness and scaling, all of which resolved without intervention. This study shows that the use of the tea tree oil products significantly improved mild to moderate acne and that the products were well tolerated. © 2016 The Australasian College of Dermatologists.
Low, Pauline; Clark, Amanda M; Chou, Tz-Chong; Chang, Tsu-Chung; Reynolds, Maxwell; Ralph, Stephen J
Melaleuca alternifolia concentrate (MAC) is a mixture predominantly composed of monoterpenoids and sesquiterpenes, refined from the essential oil of the tea tree by removing up to 99% of the more toxic, hydrophobic monoterpenes. MAC was examined here for its immunomodulatory effects on the human THP1 and murine RAW264.7 myeloid leukemic cell lines as models for macrophage-like cells. Firstly, MAC levels were determined that did not affect either the survival or proliferation of these cell lines in vitro. Next, the levels of lipopolysaccharide (LPS)-induced production of cytokines (IL-6, TNFα, IL-10, GM-CSF, IFNγ and IL-3) were examined from the myeloid cell lines using multiplex assays. Many of the LPS-inducible cytokines produced by either cell lines could be significantly inhibited by MAC. Closer examination of the mechanism of action of MAC showed that it inhibited the LPS-induced activation of IκB phosphorylation and nuclear factor (NF)-κB signalling and translocation, inhibiting iNOS protein expression and NO production. These results demonstrate that MAC exerts its immunomodulatory effects by inhibiting NF-κB signalling activation and levels of cytokine production by macrophage-like cell lines. Crown Copyright © 2015. Published by Elsevier B.V. All rights reserved.
Christoph, F; Kaulfers, P M; Stahl-Biskup, E
The in vitro antibacterial and antifungal activities of Australian tea tree oil, cajuput oil, niaouli oil, kanuka oil and manuka oil as well as of a beta-triketone complex isolated from manuka oil were investigated in a constituent-oriented study. The compositions of the oils were analysed by capillary GLC and GLC-MS. The MICs for sixteen different microorganisms were determined applying the broth dilution method. Australian tea tree oil showed the best overall antimicrobial effect. The best inhibitory effects on Gram-positive bacteria and dermatophytes were achieved with manuka oil due to its beta-triketone content.
Sinha, Priyam; Srivastava, Shruti; Mishra, Nidhi; Singh, Dhananjay Kumar; Luqman, Suaib; Chanda, Debabrata; Yadav, Narayan Prasad
To develop and optimize nanoemulsion (NE)-based emulgel (EG) formulation as a potential vehicle for topical delivery of tea tree oil (TTO). Central composite design was adopted for optimizing the processing conditions for NE preparation by high energy emulsification method viz. surfactant concentration, co-surfactant concentration, and stirring speed. The optimized NE was developed into emulgel (EG) using pH sensitive polymer Carbopol 940 and triethanolamine as alkalizer. The prepared EG was evaluated for its pH, viscosity, and texture parameters, ex vivo permeation at 37 °C and stability. Antimicrobial evaluation of EG in comparison to conventional gel and pure TTO was also carried out against selected microbial strains. Optimized NE had particle size and zeta potential of 16.23 ± 0.411 nm and 36.11 ± 1.234 mV, respectively. TEM analysis revealed the spherical shape of droplets. The pH of EG (5.57 ± 0.05 ) was found to be in accordance with the range of human skin pH. EG also illustrated efficient permeation (79.58 μL/cm(2)) and flux value (JSS) of 7.96 μL cm(2)/h through skin in 10 h. Viscosity and texture parameters, firmness (9.3 ± 0.08 g), spreadability (2.26 ± 0.06 mJ), extrudability (61.6 ± 0.05 mJ), and adhesiveness (8.66 ± 0.08 g) depict its suitability for topical application. Antimicrobial evaluation of EG with same amount of TTO as conventional gel revealed broader zones of growth inhibitions against all the selected microbial strains. Moreover, EG was also found to be nonirritant (PII 0.0833). These parameters were consistent over 90 d. TTO EG turned out to be a promising vehicle for the topical delivery of TTO with enhanced therapeutic efficacy.
Omar, Alaa El-din K; Belal, Elsayed B; El-Abd, Abd El-Naiem A
Sixteen-year-old navel orange trees at a private orchard located in Kafer El-Sheikh Governorate, Egypt, were used in this study. Compost tea (CT) and filtrate biogas slurry liquid (FLB) were applied at two different concentrations (50% and 100%); control trees were sprayed with water Trees treated with CT at 100% were the highest in yield, fruit weight, and vitamin C, whereas the highest percentage of fruit set, fruit number and soluble solid content (SSC), lowest fruit drop, and highest reducing and total sugars were in trees treated with 100% FLB. Concentrations at 50% for both foliar application (CT and FLB) improved yield and fruit characteristics than control treatment. Generally, using a foliar application of compost tea and filtrate biogas slurry liquid at (100%) treatments as food nutrients could be recommended to improve the yield and fruit quality of navel orange fruits under the current study conditions.
Omar, Alaa El-Din Kh; Belal, Elsayed B; El-Abd, Abd El-Naiem A
Sixteen-year-old navel orange trees at a private orchard located in Kafer El-Sheikh Governorate, Egypt, were used in this study. Compost tea (CT) and filtrate biogas slurry liquid (FLB) were applied at two different concentrations (50% and 100%); control trees were sprayed with water. Trees treated with CT at 100% were the highest in yield, fruit weight, and vitamin C, whereas the highest percentage of fruit set, fruit number, and soluble solid content (SSC), lowest fruit drop, and highest reducing and total sugars were in trees treated with 100% FLB. Concentrations at 50% for both foliar application (CT and FLB) improved yield and fruit characteristics than control treatment. Generally, using a foliar application of compost tea and filtrate biogas slurry liquid at (100%) treatments as food nutrients could be recommended to improve the yield and fruit quality of navel orange fruits under the current study conditions. [Box: see text].
Pazinatto Boito, Jhonatan; Santos, Roberto C; Vaucher, Rodrigo A; Raffin, Renata; Machado, Gustavo; Tonin, Alexandre A; Da Silva, Aleksandro S
Our research aimed to test the effects of Melaleuca alternifolia oil (pure and in nanocapsules) in the control of Rhipicephalus microplus in dairy cattle. For this purpose, the in vivo studies used 15 cows distributed in three different groups with the same number of animals. Five cows remained untreated (Group A), representing the control group; other five cows were sprayed with TTO (at 5%) in its pure form (Group B); and five cows were sprayed with nanocapsules of TTO (at 0.75%) (Group C). On days 1 and 4 post-treatments (PT), all cows had their ticks counted. On day 1 PT, two ticks from each cow were collected to evaluate the effect of the treatment on ticḱs reproduction (in vitro assays). The pure form of TTO caused a significant reduction (P<0.05) in the number of ticks from the Group B compared to the Group A on day 4 PT. However, there was no significant difference in the number of ticks on cows from Groups A and C after treatment (P>0.05). Treatment with TTO in nanocapsules (Group C) interfered with R. microplus reproduction, leading to lower oviposition by female ticks and hatchability (34.5% of efficacy). On the other hand, TTO oil (Group B) did not interfere on ticḱs reproduction, i.e. showed higher hatchability than the control group. Therefore, it is possible to conclude that pure TTO has an acaricidal effect in dairy cows, in addition to an effect on ticḱs reproduction when used its nanocapsulated form. Copyright © 2016 Elsevier B.V. All rights reserved.
Schnitzler, P; Schön, K; Reichling, J
The antiviral effect of Australian tea tree oil (TTO) and eucalyptus oil (EUO) against herpes simplex virus was examined. Cytotoxicity of TTO and EUO was evaluated in a standard neutral red dye uptake assay. Toxicity of TTO and EUO was moderate for RC-37 cells and approached 50% (TC50) at concentrations of 0.006% and 0.03%, respectively. Antiviral activity of TTO and EUO against herpes simplex virus type 1 (HSV-1) and herpes simplex virus type 2 (HSV-2) was tested in vitro on RC-37 cells using a plaque reduction assay. The 50% inhibitory concentration (IC50) of TTO for herpes simplex virus plaque formation was 0.0009% and 0.0008% and the IC50 of EUO was determined at 0.009% and 0.008% for HSV-1 and HSV-2, respectively. Australian tea tree oil exhibited high levels of virucidal activity against HSV-1 and HSV-2 in viral suspension tests. At noncytotoxic concentrations of TTO plaque formation was reduced by 98.2% and 93.0% for HSV-1 and HSV-2, respectively. Noncytotoxic concentrations of EUO reduced virus titers by 57.9% for HSV-1 and 75.4% for HSV-2. Virus titers were reduced significantly with TTO, whereas EUO exhibited distinct but less antiviral activity. In order to determine the mode of antiviral action of both essential oils, either cells were pretreated before viral infection or viruses were incubated with TTO or EUO before infection, during adsorption or after penetration into the host cells. Plaque formation was clearly reduced, when herpes simplex virus was pretreated with the essential oils prior to adsorption. These results indicate that TTO and EUO affect the virus before or during adsorption, but not after penetration into the host cell. Thus TTO and EUO are capable to exert a direct antiviral effect on HSV. Although the active antiherpes components of Australian tea tree and eucalyptus oil are not yet known, their possible application as antiviral agents in recurrent herpes infection is promising.
Paul, Asosii; Jha, Ashwani; Bhardwaj, Shruti; Singh, Sewa; Shankar, Ravi; Kumar, Sanjay
Tea [Camellia sinensis (L.) O. Kuntze] is a perennial tree which undergoes winter dormancy and unlike deciduous trees, the species does not shed its leaves during winters. The present work dissected the molecular processes operating in the leaves during the period of active growth and winter dormancy through transcriptome analysis to understand a long-standing question: why should tea be a non-deciduous species? Analyses of 24,700 unigenes obtained from 57,767 primarily assembled transcripts showed (i) operation of mechanisms of winter tolerance, (ii) down-regulation of genes involved in growth, development, protein synthesis and cell division, and (iii) inhibition of leaf abscission due to modulation of senescence related processes during winter dormancy in tea. These senescence related processes exhibited modulation to favour leaf abscission (i) in deciduous Populus tremula during winters, and (ii) also in tea but under osmotic stress during which leaves also abscise. These results validated the relevance of the identified senescence related processes for leaf abscission and suggested their operation when in need in tea.
Xu, Jiayu; Shao, Xingfeng; Li, Yonghua; Wei, Yingying; Xu, Feng; Wang, Hongfei
Tea tree oil (TTO), a volatile essential oil, has been widely used as an antimicrobial agent. However, the mechanism underlying TTO antifungal activity is not fully understood. In this study, a comprehensive metabolomics survey was undertaken to identify changes in metabolite production in Botrytis cinerea cells treated with TTO. Significant differences in 91 metabolites were observed, including 8 upregulated and 83 downregulated metabolites in TTO-treated cells. The results indicate that TTO inhibits primary metabolic pathways through the suppression of the tricarboxylic acid (TCA) cycle and fatty acid metabolism. Further experiments show that TTO treatment decreases the activities of key enzymes in the TCA cycle and increases the level of hydrogen peroxide (H2O2). Membrane damage is also induced by TTO treatment. We hypothesize that the effect of TTO on B. cinerea is achieved mainly by disruption of the TCA cycle and fatty acid metabolism, resulting in mitochondrial dysfunction and oxidative stress.
Cuttle, Leila; Kempf, Margit; Kravchuk, Olena; George, Narelle; Liu, Pei-Yun; Chang, Hong-En; Mill, Julie; Wang, Xue-Qing; Kimble, Roy M
Many alternative therapies are used as first aid treatment for burns, despite limited evidence supporting their use. In this study, Aloe vera, saliva and a tea tree oil impregnated dressing (Burnaid) were applied as first aid to a porcine deep dermal contact burn, compared to a control of nothing. After burn creation, the treatments were applied for 20 min and the wounds observed at weekly dressing changes for 6 weeks. Results showed that the alternative treatments did significantly decrease subdermal temperature within the skin during the treatment period. However, they did not decrease the microflora or improve re-epithelialisation, scar strength, scar depth or cosmetic appearance of the scar and cannot be recommended for the first aid treatment of partial thickness burns.
Harkenthal, M; Layh-Schmitt, G; Reichling, J
In vitro assays using a variety of essential oils revealed a particularly high antibacterial effect of Australian tea tree oil (TTO) on a great number of gram-negative and gram-positive bacteria of unrelated phylogenetic origin. In the present study, the susceptibility of cell wall-less bacteria such as the human pathogenic bacterium Mycoplasma pneumoniae to Australian tea tree oil was examined. The minimum inhibitory concentration (MIC) was determined to be 0.006% (v/v) TTO for the wild type and to 0.003% (v/v) TTO for mutants of M. pneumoniae which lost the ability to adhere to host cells (cytadherence-negative). The MIC and the MBC (minimum bactericidal concentration) for M. pneumoniae are 100 times lower than those for all other eubacteria tested. Electron microscopy with negatively stained cells as well as with ultrathin sections revealed a tendency to ovoid or round cells after oil treatment whereas the untreated cells of the wild type exhibit a flask-shaped morphology with a tip-like structure at one pole of the cell. The integrity of the mycoplasmal membrane seems not to be affected by TTO since no leakage of the Mycoplasma cell was observed after oil treatment. In the HET-CAM test TTO did not show any visible signs of irritation in concentrations less than 25%. Although the active component in TTO that has anti-mycoplasmal activity is not known, it seems very promising to use TTO tentatively for mouth washing and inhalation in case of Mycoplasma-pneumoniae-infection.
Liao, Min; Xiao, Jin-Jing; Zhou, Li-Jun; Liu, Yang; Wu, Xiang-Wei; Hua, Ri-Mao; Wang, Gui-Rong; Cao, Hai-Qun
The cereal weevil, Sitophilus zeamais is one of the most destructive pests of stored cereals worldwide. Frequent use of fumigants for managing stored-product insects has led to the development of resistance in insects. Essential oils from aromatic plants including the tea oil plant, Melaleuca alternifolia may provide environmentally friendly alternatives to currently used pest control agents. However, little is known about molecular events involved in stored-product insects in response to plant essential oil fumigation. M. alternifolia essential oil was shown to possess the fumigant toxicity against S. zeamais. The constituent, terpinen-4-ol was the most effective compound for fumigant toxicity. M. alternifolia essential oil significantly inhibited the activity of three enzymes in S. zeamais, including two detoxifying enzymes, glutathione S-transferase (GST), and carboxylesterase (CarE), as well as a nerve conduction enzyme, acetylcholinesterase (AChE). Comparative transcriptome analysis of S. zeamais through RNA-Seq identified a total of 3,562 differentially expressed genes (DEGs), of which 2,836 and 726 were up-regulated and down-regulated in response to M. alternifolia essential oil fumigation, respectively. Based on gene ontology (GO) analysis, the majority of DEGs were involved in insecticide detoxification and mitochondrial function. Furthermore, an abundance of DEGs mapped into the metabolism pathway in the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway database were associated with respiration and metabolism of xenobiotics, including cytochrome P450s, CarEs, GSTs, and ATP-binding cassette transporters (ABC transporters). Some DEGs mapped into the proteasome and phagosome pathway were found to be significantly enriched. These results led us to propose a model of insecticide action that M. alternifolia essential oil likely directly affects the hydrogen carrier to block the electron flow and interfere energy synthesis in mitochondrial respiratory chain
Liao, Min; Xiao, Jin-Jing; Zhou, Li-Jun; Liu, Yang; Wu, Xiang-Wei; Hua, Ri-Mao; Wang, Gui-Rong; Cao, Hai-Qun
Background The cereal weevil, Sitophilus zeamais is one of the most destructive pests of stored cereals worldwide. Frequent use of fumigants for managing stored-product insects has led to the development of resistance in insects. Essential oils from aromatic plants including the tea oil plant, Melaleuca alternifolia may provide environmentally friendly alternatives to currently used pest control agents. However, little is known about molecular events involved in stored-product insects in response to plant essential oil fumigation. Results M. alternifolia essential oil was shown to possess the fumigant toxicity against S. zeamais. The constituent, terpinen-4-ol was the most effective compound for fumigant toxicity. M. alternifolia essential oil significantly inhibited the activity of three enzymes in S. zeamais, including two detoxifying enzymes, glutathione S-transferase (GST), and carboxylesterase (CarE), as well as a nerve conduction enzyme, acetylcholinesterase (AChE). Comparative transcriptome analysis of S. zeamais through RNA-Seq identified a total of 3,562 differentially expressed genes (DEGs), of which 2,836 and 726 were up-regulated and down-regulated in response to M. alternifolia essential oil fumigation, respectively. Based on gene ontology (GO) analysis, the majority of DEGs were involved in insecticide detoxification and mitochondrial function. Furthermore, an abundance of DEGs mapped into the metabolism pathway in the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway database were associated with respiration and metabolism of xenobiotics, including cytochrome P450s, CarEs, GSTs, and ATP-binding cassette transporters (ABC transporters). Some DEGs mapped into the proteasome and phagosome pathway were found to be significantly enriched. These results led us to propose a model of insecticide action that M. alternifolia essential oil likely directly affects the hydrogen carrier to block the electron flow and interfere energy synthesis in
Huynh, Q.; Phan, T. D.; Thieu, V. Q. Q.; Tran, S. T.; Do, S. H.
Tea tree oil (TTO) comes from the leaves of Melaleuca alternifornia that belongs to the myrtle family (Myrtaceae). It is one of the most powerful immune system stimulants and sorts out most viral, bacterial and fungal infections in a snap, while it is great to heal wounds and acnes. In Vietnam, Melaleuca trees can grow on acid land that stretches in a large portion of lands in the Mekong Delta region. So, there are some Melaleuca plantations developed under the Vietnamese government plans of increasing plantation forests now. However, TTO contains various amounts of 1,8-cineole that causes skin irritant. So TTO purification is very necessary. In this study, the purification of TTO that meet International Standard ISO 4730 was carried out via two steps. The first step is steam distillation to obtain crude TTO (terpinen-4-ol 35% v/v) and the average productivity is among 2.37% (v/wet-wt) or 1.23% (v/dry-wt). In the second step, the cleaned TTO is collected by vacuum distillation column and extraction yield of the whole process is about 0.3% (w/w). Besides, high concentration essential oil was applied in the cosmetic products to increase its commercial value.
Zeng, Yanling; Tan, Xiaofeng; Zhang, Lin; Jiang, Nan; Cao, Heping
Tea oil tree (Camellia oleifera, Co) provides a fine edible oil source in China. Tea oil from the seeds is very beneficial to human health. Fructose-1,6-bisphosphate aldolase (FBA) hydrolyzes fructose-1,6-bisphosphate into dihydroxyacetone phosphate and glyceraldehyde 3-phosphate, two critical metabolites for oil biosynthesis. The objectives of this study were to identify FBA genes and investigate the relationship between FBA gene expression and oil content in developing seeds of tea oil tree. In this paper, four developmentally up-regulated CoFBA genes were identified in Camellia oleifera seeds based on the transcriptome from two seed developmental stages corresponding to the initiation and peak stages of lipid biosynthesis. The expression of CoFBA genes, along with three key oil biosynthesis genes CoACP, CoFAD2 and CoSAD were analyzed in seeds from eight developmental stages by real-time quantitative PCR. The oil content and fatty acid composition were also analyzed. The results showed that CoFBA and CoSAD mRNA levels were well-correlated with oil content whereas CoFAD2 gene expression levels were correlated with fatty acid composition in Camellia seeds. We propose that CoFBA and CoSAD are two important factors for determining tea oil yield because CoFBA gene controls the flux of key intermediates for oil biosynthesis and CoSAD gene controls the synthesis of oleic acid, which accounts for 80% of fatty acids in tea oil. These findings suggest that tea oil yield could be improved by enhanced expression of CoFBA and CoSAD genes in transgenic plants.
Zeng, Yanling; Tan, Xiaofeng; Zhang, Lin; Jiang, Nan; Cao, Heping
Tea oil tree (Camellia oleifera, Co) provides a fine edible oil source in China. Tea oil from the seeds is very beneficial to human health. Fructose-1,6-bisphosphate aldolase (FBA) hydrolyzes fructose-1,6-bisphosphate into dihydroxyacetone phosphate and glyceraldehyde 3-phosphate, two critical metabolites for oil biosynthesis. The objectives of this study were to identify FBA genes and investigate the relationship between FBA gene expression and oil content in developing seeds of tea oil tree. In this paper, four developmentally up-regulated CoFBA genes were identified in Camellia oleifera seeds based on the transcriptome from two seed developmental stages corresponding to the initiation and peak stages of lipid biosynthesis. The expression of CoFBA genes, along with three key oil biosynthesis genes CoACP, CoFAD2 and CoSAD were analyzed in seeds from eight developmental stages by real-time quantitative PCR. The oil content and fatty acid composition were also analyzed. The results showed that CoFBA and CoSAD mRNA levels were well-correlated with oil content whereas CoFAD2 gene expression levels were correlated with fatty acid composition in Camellia seeds. We propose that CoFBA and CoSAD are two important factors for determining tea oil yield because CoFBA gene controls the flux of key intermediates for oil biosynthesis and CoSAD gene controls the synthesis of oleic acid, which accounts for 80% of fatty acids in tea oil. These findings suggest that tea oil yield could be improved by enhanced expression of CoFBA and CoSAD genes in transgenic plants. PMID:25215538
Introduction The prevention and control of caries necessitates the elimination of cariogenic bacteria and cavity disinfectants have proved to play a major role in achieving the goal. The use of phytotherapy is trending and many natural products have shown anti-microbial properties which can be used as cavity disinfectant in the field of dentistry. Aim The aim of this study was to compare the efficacy of herbal antibacterial agents (Tea Tree Oil (TTO) and Aloe vera) with commercially available 2% chlorhexidine (CHX) as cavity disinfectant for use in minimally invasive dentistry. Materials and Methods The study included three test groups, Group I (2% chlorhexidine), Group II (tea tree oil), Group III (Aloe vera gel) with a control group (distilled water). Ten patients with atleast one tooth with an occlusal or occluso-proximal lesion suitable for Atraumatic Restorative Treatment (ART) were selected for each group, dentinal samples were collected using sterile spoon excavators at three stages from each tooth viz., pre-excavation, post-excavation and post-disinfection of the cavities. These dentinal samples were subjected to microbiological analysis for Total Viable Count (TVC). The data collected were statistically analysed using ANOVA and Bonferroni post-hoc test. Results The results of present study showed that there was a statistically significant reduction in TVC when compared between pre and post excavation in all the groups (p<0.05) and post- excavation and post-disinfection in all the test groups (p<0.05) (except control group). Post-disinfection, 2% chlorhexidine showed highest reduction in TVC followed by 1% tea tree oil and aloe vera gel. Conclusion Natural antibacterial agents like tea tree oil and aloe vera could be effectively used as cavity disinfectants which will help in minimizing secondary caries and rendering a long term restorative success. PMID:28892888
Patri, Gaurav; Sahu, Aliva
The prevention and control of caries necessitates the elimination of cariogenic bacteria and cavity disinfectants have proved to play a major role in achieving the goal. The use of phytotherapy is trending and many natural products have shown anti-microbial properties which can be used as cavity disinfectant in the field of dentistry. The aim of this study was to compare the efficacy of herbal antibacterial agents (Tea Tree Oil (TTO) and Aloe vera) with commercially available 2% chlorhexidine (CHX) as cavity disinfectant for use in minimally invasive dentistry. The study included three test groups, Group I (2% chlorhexidine), Group II (tea tree oil), Group III (Aloe vera gel) with a control group (distilled water). Ten patients with atleast one tooth with an occlusal or occluso-proximal lesion suitable for Atraumatic Restorative Treatment (ART) were selected for each group, dentinal samples were collected using sterile spoon excavators at three stages from each tooth viz., pre-excavation, post-excavation and post-disinfection of the cavities. These dentinal samples were subjected to microbiological analysis for Total Viable Count (TVC). The data collected were statistically analysed using ANOVA and Bonferroni post-hoc test. The results of present study showed that there was a statistically significant reduction in TVC when compared between pre and post excavation in all the groups (p<0.05) and post- excavation and post-disinfection in all the test groups (p<0.05) (except control group). Post-disinfection, 2% chlorhexidine showed highest reduction in TVC followed by 1% tea tree oil and aloe vera gel. Natural antibacterial agents like tea tree oil and aloe vera could be effectively used as cavity disinfectants which will help in minimizing secondary caries and rendering a long term restorative success.
Dalwai, Sameen; Rodrigues, Shobha J; Baliga, Shrikala; Shenoy, Vidya K; Shetty, Thilak B; Pai, Umesh Y; Saldanha, Sharon
Candida albicans-associated denture stomatitis is the most common type of denture stomatitis seen in denture wearers. This study evaluates and compares the antifungal action of fluconazole, chlorhexidine gluconate and tea tree oil on heat-polymerised denture base resin, which has been previously contaminated with C. albicans grown in BHI broth. Seventy-five specimens were immersed in BHI broth previously inoculated with C. albicans and stored for 3 h at 37°C. They were divided into five groups (n = 15): G1: 2% chlorhexidine solution; G2: 100% pure pharmaceutical grade tea tree oil; G3: 65 μg/ml fluconazole solution; C1: specimens not disinfected; C2: specimens not contaminated with Candida. Each specimen was then transferred to individual tubes containing BHI broth and incubated for 24 h. Culture media turbidity was evaluated for absorbance over a period of 14 days using a microplate reader. It was observed that the lower the absorbance, the stronger the antimicrobial action. Statistical analysis was performed (two-way anova and Bonferroni test, p < 0.001). Chlorhexidine and tea tree oil inhibited Candida up to the 14th day, whereas antifungal effect of fluconazole was not significant after the 7th day. Tea tree oil and chlorhexidine gluconate are more effective than fluconazole in inhibiting C. albicans growth on heat-polymerised acrylic resin. © 2014 John Wiley & Sons A/S and The Gerodontology Association. Published by John Wiley & Sons Ltd.
Low, W L; Martin, C; Hill, D J; Kenward, M A
The activity of alternative antimicrobial agents such as tea tree oil (TTO) and silver ions (Ag(+) ) with multiple target sites impedes the development of antibacterial resistance and might be useful in improving the current treatment strategies for various chronic wound infections. In this study, liposome-encapsulated TTO, Ag(+) and TTO plus Ag(+) were added to suspension cultures of Pseudomonas aeruginosa (Ps. aeruginosa), Staphylococcus aureus (Staph. aureus) and Candida albicans (C. albicans). Treatment of these cultures using the agents in combination at subminimal lethal concentrations resulted in an enhanced loss of viability compared to treatment with individual agents. The effective concentration, elimination time (to the limit of detection, LOD) and fractional lethal concentration index (FLCI) of liposomal agents in combination were as follows: Candida albicans: 0·05% v/v TTO:PVA30-70 kDa : 8·9 × 10(-5) % w/v Ag(+) :PVA30-70 kDa : 2·0 h, FLCI = 0·73 (indifferent), Staphylococcus aureus: 0·05% v/v TTO:PVA30-70 kDa : 6·0 × 10(-4) % w/v Ag(+) :PVA30-70 kDa : 1·5 h, FLCI = 0·38 (synergistic), Pseudomonas aeruginosa: 0·25% v/v TTO:PVA30-70 kDa : 3·2 × 10(-4) % w/v Ag(+) :PVA30-70 kDa : 30 min, FLCI = 0·33 (synergistic). These results show the potential for improving antimicrobial efficacy by delivering lower effective concentrations of alternative agents, via controlled release systems. NB All values denoted as %w/vAg(+) refer to the concentration of silver ions. In this study, we have shown that encapsulating silver (as the ion Ag(+) ) and tea tree oil (singly and in combination) in a controlled release liposomal carrier system can improve their antimicrobial efficacy as well as reduce the effective concentration required. These findings may impact on the problems of agent toxicity caused by the need for high effective doses or microbial resistance where long term application is required. © 2013 The Society for Applied
Meesters, R J W; Duisken, M; Hollender, J
1. The cytochrome P450-mediated metabolism of the tea tree oil ingredient p-cymene (p-isopropyltoluene) was studied by the application of in vitro enzymatic assays using different recombinant human cytochrome P450 enzymes. 2. In total, four enzymatic products were identified by gas chromatography-mass spectrometry. The enzymatic products identified were: thymol (2-isopropyl-5-methylphenol), p-isopropylbenzyl alcohol, p,alpha,alpha-trimethylbenzyl alcohol, and p-isopropylbenzaldehyde. 3. The enzymatic products of p-cymene resulted from catalysed enzymatic arene-epoxidation and hydroxylation reactions by the studied cytochrome P450 enzymes. 4. An in vivo study could only confirm the formation of one enzymatic product, namely thymol. Thymol was identified after enzymatic hydrolysis of glucuronide and sulphate conjugates in collected blood and urine samples. 5. The obtained results may help to increase the understanding of cases where skin sensitization and irritation by tea tree oil-containing products that are involved with allergic reactions of users of these products. The results also indicate that skin sensitization and irritation reactions not only can be explained by the frequently in literature reported auto-oxidation of tea tree resulting in bioactive oxidized products, but also now by the formation of epoxide intermediates resulting from catalysed arene-epoxidation reactions by selected human cytochrome P450 enzymes which are also located in different organs in humans.
Liu, Z; Meng, R; Zhao, X; Shi, C; Zhang, X; Zhang, Y; Guo, N
Listeria monocytogenes (L. monocytogenes) is a Gram-positive bacterium that causes infections in humans. In this study, the effects of tea tree oil (TTO) at subinhibitory concentrations on L. monocytogenes growth and two important exotoxin proteins secreted by L. monocytogenes were researched. Treatment with half of minimal inhibitory concentration of TTO demonstrated very little or no reduction in numbers of viable ATCC 19115 cells. Listeriolysin O (LLO) and p60, were investigated. A listeriolysin assay was used to investigate the hemolytic activities of L. monocytogenes exposed to TTO, and the secretion of LLO and p60 was detected by immunoblot analysis. Additionally, real-time RT-PCR was used to analyse the influence of TTO on the transcription of LLO and p60 encoded genes hly and iap respectively. According to our experimental results, we propose that TTO could be used as a promising natural compound against L. monocytogenes and its virulence factors.
Catanzano, O; Straccia, M C; Miro, A; Ungaro, F; Romano, I; Mazzarella, G; Santagata, G; Quaglia, F; Laurienzo, P; Malinconico, M
In this paper we propose an in situ forming ionically cross-linked alginate (Alg) hydrogel delivering a Tea Tree Oil microemulsion (MeTTO) and potentially useful as an advanced dressing for infected wounds. Alg hydrogels were prepared by a spray-by-spray deposition method with the aim to minimize the discomforts during application. From pseudoternary phase diagrams, it was found that proper combination of TTO, water, polysorbate 80 and ethanol gave stable spherical MeTTO with good antimicrobial activity. On this basis, MeTTO at 20% TTO was selected for further inclusion in an Alg hydrogel prepared by alternating sprays of Alg/MeTTO and calcium chloride solutions. Homogeneous dispersion of MeTTO inside cross-linked Alg was assessed by different macroscopic and microscopic methods demonstrating the superior propensity of MeTTO to be integrated in the water-based hydrogel as compared to TTO. Antimicrobial effect of Alg/MeTTO hydrogels on Escherichia Coli strains was remarkable, highlighting the potential of the system as bioactive wound dressing.
Mondello, Francesca; De Bernardis, Flavia; Girolamo, Antonietta; Salvatore, Giuseppe; Cassone, Antonio
A tea tree oil (TTO) preparation of defined chemical composition was studied, using a microbroth method, for its in vitro activity against 115 isolates of Candida albicans, other Candida species and Cryptococcus neoformans. The fungal strains were from HIV-seropositive subjects, or from an established type collection, including reference and quality control strains. Fourteen strains of C. albicans resistant to fluconazole and/or itraconazole were also assessed. The same preparation was also tested in an experimental vaginal infection using fluconazole-itraconazole-susceptible or -resistant strains of C. albicans. TTO was shown to be active in vitro against all tested strains, with MICs ranging from 0.03% (for C. neoformans) to 0.25% (for some strains of C. albicans and other Candida species). Fluconazole- and/or itraconazole-resistant C. albicans isolates had TTO MIC50s and MIC90s of 0.25% and 0.5%, respectively. TTO was highly efficacious in accelerating C. albicans clearance from experimentally infected rat vagina. Three post-challenge doses of TTO (5%) brought about resolution of infection regardless of whether the infecting C. albicans strain was susceptible or resistant to fluconazole. Overall, the use of a reliable animal model of infection has confirmed and extended our data on the therapeutic effectiveness of TTO against fungi, in particular against C. albicans.
Low, W L; Martin, C; Hill, D J; Kenward, M A
Tea tree oil (TTO) and silver ions (Ag(+)), either alone or in combination with other antimicrobial compounds, have been used in the treatment of topical infections. However, there appears to be little data on the efficacy of TTO combined with silver in the absence of any other agents. TTO and Ag(+) were added, alone and in combination, to suspension cultures of Pseudomonas aeruginosa, Staphylococcus aureus and Candida albicans. Treatment of these cultures with TTO and Ag(+) at sub-minimal lethal concentrations resulted in an enhanced loss of viability compared with treatment with individual agents. The order of sensitivity to the combined agents was P. aeruginosa>S. aureus>C. albicans. The fractional lethal concentration index (FLCI) showed that these combinations of TTO and Ag(+) exerted a synergistic effect against P. aeruginosa (FLCI=0.263) and an indifferent effect against S. aureus and C. albicans (FLCI=0.663 and 1.197, respectively). The results indicate that combining these antimicrobial agents may be useful in decreasing the concentration of antimicrobial agents required to achieve an effective reduction in opportunistic pathogenic microorganisms that typically infect wounds.
Reichling, Jürgen; Landvatter, Uwe; Wagner, Heike; Kostka, Karl-Heinz; Schaefer, Ulrich F
Essential oils are widely used in pharmaceutical and cosmetic preparations e.g. as fragrance, active ingredient or penetration enhancer. However, reports on skin absorption are rare. Therefore, the aim of our study was to investigate the capability of terpinen-4-ol, the main compound of Australian tea tree oil (TTO), to permeate human skin. In static Franz diffusion cells permeation experiments with heat separated human epidermis were carried out using infinite dosing conditions and compared to liberation experiments. The flux values of three different semisolid preparations with 5% TTO showed the rank order semisolid O/W emulsion (0.067 microl/cm2 h) > white petrolatum (0.051 microl/cm2 h) > ambiphilic cream (0.022 microl/cm2 h). In comparison to the flux value obtained with the native TTO (0.26 microl/cm2 h), the flux values are remarkably reduced due to the lower amount of terpinen-4-ol. P(app) values for cream (2.74+/-0.06 x 10(-7) cm/s) and native TTO (1.62+/-0.12 x 10(-7) cm/s) are comparable whereas white petrolatum (6.36+/-0.21 x 10(-7) cm/s) and semisolid O/W emulsion (8.41+/-0.15 x 10(-7) cm/s) demonstrated higher values indicating a penetration enhancement. No relationship between permeation and liberation was found.
Li, Yonghua; Shao, Xingfeng; Xu, Jiayu; Wei, Yingying; Xu, Feng; Wang, Hongfei
The purpose of this study was to investigate the antifungal activities and possible mechanisms of tea tree oil (TTO) against Botrytis cinerea and Penicillium expansum in vitro and in vivo. The results show that TTO exhibits dose-dependent antifungal activity against both pathogens, but P. expansum is less sensitive than B. cinerea to TTO not only in the in vitro test but also in artificially inoculated cherry fruits. TTO vapor treatment reduced the decay caused by these pathogens in inoculated cherry fruits, but the effect on P. expansum was less than that on B. cinerea. While the total lipid and ergosterol contents of the cell membrane are greater in P. expansum than in B. cinerea, TTO treatment lowers the total lipid content in the membranes of both species by well over 50%, and ergosterol content is reduced to a greater extent in B. cinerea than in P. expansum. In both pathogens, TTO alters mycelial morphology and cellular ultrastructure. Oxygen consumption measurements show that TTO inhibits respiratory metabolism via the tricarboxylic acid cycle pathway in both pathogens, though more severely in B. cinerea than in P. expansum. The relatively decreased sensitivity of P. expansum to TTO may be due to the fact that TTO causes less disruption of the cell membrane in this organism, and higher inhibition the respiratory metabolism to the extent observed in B. cinerea.
Rahman, Betul; Alkawas, Sausan; Al Zubaidi, Elaf A; Adel, Omar I; Hawas, Nuha
The aim of this study was to compare the antiplaque and antigingivitis effects of a mouthwash containing tea tree oil (TTO) with a cetylpyridinium chloride (CPC) mouthwash. This was a randomized 4 × 4, controlled, cross-over, involving 20 healthy volunteers in a 5-day plaque re-growth model. Test mouthwashes were TTO (Tebodont(®)) and a mouthwash containing CPC 0.05% (Aquafresh(®)). A 0.12% chlorhexidine (CHX) mouthwash (Oro-Clense(®)) was used as positive and colored water (placebo [PLB]) as negative controls. Gingival bleeding index (GBI) and plaque index (PI) scores were recorded before and after each test period. Test periods were separated with 2 weeks washout period. All four mouthwashes significantly (P < 0.001) reduced the GBI scores when compared to the baseline GBI scores. There was no significant difference between PLB and active mouthwashes in the GBI scores. CHX and CPC mouthwashes were found more effective in reducing the PI scores than TTO and PLB mouthwashes. There was no significant difference in PI scores of CHX and CPC mouthwashes. 0.05% CPC mouthwash can be an alternative to CHX mouthwash since it is alcohol free and found as efficient as CHX in dental plaque reduction with lesser side effects. More studies are needed to test antigingivitis effects of the mouthwashes used in this study, preferably without initial scaling and polishing.
Low, Wan-Li; Kenward, Ken; Britland, Stephen T; Amin, Mohd Cim; Martin, Claire
The increasing occurrence of hospital-acquired infections and the emerging problems posed by antibiotic-resistant microbial strains have both contributed to the escalating cost of treatment. The presence of infection at the wound site can potentially stall the healing process at the inflammatory stage, leading to the development of a chronic wound. Traditional wound treatment regimes can no longer cope with the complications posed by antibiotic-resistant strains; hence, there is a need to explore the use of alternative antimicrobial agents. Pre-antibiotic compounds, including heavy metal ions and essential oils, have been re-investigated for their potential use as effective antimicrobial agents. Essential oils have potent antimicrobial, antifungal, antiviral, anti-inflammatory, antioxidant and other beneficial therapeutic properties. Similarly, heavy metal ions have also been used as disinfecting agents because of their broad spectrum activities. Both of these alternative antimicrobials interact with many different intracellular components, thereby resulting in the disruption of vital cell functions and eventually cell death. This review will discuss the application of essential oils and heavy metal ions, particularly tea tree oil and silver ions, as alternative antimicrobial agents for the treatment of chronic, infected wounds. © 2016 Medicalhelplines.com Inc and John Wiley & Sons Ltd.
F Souza, Carine; Baldissera, Matheus D; A Vaucher, Rodrigo; Lopes, Leonardo Q S; Vizzotto, Bruno S; Raffin, Renata P; Santos, Roberto C V; L da Veiga, Marcelo; U M da Rocha, Maria Izabel; Stefani, Lenita M; Baldisserotto, Bernardo
Aeromonas hydrophila is one of the main causative agent of high mortality and significative economic losses in aquaculture and has become increasingly resistant to conventional antibiotics. One feasible alternative to control and treat it is the use of essential oils. This study aimed to evaluate A. hydrophila susceptibility to tea tree oil (TTO-Melaleuca alternifolia) in vivo, and the effect of this treatment. In vivo tests were performed using silver catfish (Rhamdia quelen) as the experimental model. Silver catfish were treated with TTO at 25 and 50 μL/L for seven days before infection. After seven days, the fish were inoculated with A. hydrophila via intramuscularly. Treatment with TTO at 50 μL/L was able to extend longevity of infected fish, and showed 88% of therapeutic success, even though it did not show curative efficacy. TTO treatment was not toxic under these tested concentrations, since biomarkers of hepatic and renal functions were not affected, and the concentration of 50 μL/L was able to prevent increased levels of aspartate aminotransferase. There was no significative differences regarding hematological parameters (p < 0.05). Treatment with TTO 50 μL/L was able to reduce histopathological alterations usually caused by this type of bacteria in the gills, but it was unable to reduce hepatic histopathological alterations. Our results showed, for the first time, that TTO has high activity against A. hydrophila and proved to be a natural alternative to prevent and control this pathogen.
Messager, S; Hammer, K A; Carson, C F; Riley, T V
The activity of tea tree oil (TTO) and TTO-containing products was investigated according to the EN 1276 and EN 12054 European suspension methods. The activity of different concentrations of TTO, a hygienic skin wash (HSW), an alcoholic hygienic skin wash (AHSW) and an alcoholic hand rub (AHR) was investigated. These formulations were assessed in perfect conditions with the EN 12054 test, and in perfect conditions as well as in the presence of interfering substances with the EN 1276 test, against Staphylococcus aureus, Acinetobacter baumannii, Escherichia coli and Pseudomonas aeruginosa. With the latter test, the activity of the same formulations without TTO was also assessed as a control. With the EN 1276 test, the AHR achieved a >10(5)-fold reduction against all four test organisms within a 1-min contact time. The AHSW achieved a >or=10(5)-fold reduction against A. baumannii after a 1-min contact time and against S. aureus, E. coli and P. aeruginosa after a 5-min contact time. The efficacy of TTO appeared to be dependent on the formulation and the concentration tested, the concentration of interfering substances and, lastly, the organism tested. Nevertheless, 5% TTO achieved a >10(4)-fold reduction in P. aeruginosa cell numbers after a 5-min contact time in perfect conditions. TTO (5%) in 0.001% Tween 80 was significantly more active against E. coli and P. aeruginosa than against S. aureus and A. baumannii. With the EN 12054 test, after a 1-min contact time, 5% TTO in 0.001% Tween 80 and the AHSW achieved a >10(4)-fold reduction in E. coli and A. baumannii cell numbers, respectively, and the AHR achieved a >4 log10 reduction against all organisms tested. The formulations used in this study are now being tested using a novel ex vivo method as well as the in vivo European standard handwashing method EN 1499.
Chandrdas, Dithi; Jayakumar, H L; Chandra, Mahesh; Katodia, Lavleen; Sreedevi, Athira
To assess and compare the efficacy of 3% garlic extract, 0.2% tea tree oil, 0.2% chlorhexidine, 0.05% cetylpyridinium chloride, and ultravoilet (UV) toothbrush sanitizing device as toothbrush disinfectants against Streptococcus mutans. A double blind randomized controlled parallel study was done on 210 dental students. The subjects were divided into one control group using distilled water and five study groups representing 0.2% tea tree oil, 3% garlic extract, 0.2% chlorhexidine gluconate, 0.05% cetylpyridinium chloride and UV toothbrush sanitizing device. Participants were provided with new toothbrushes and toothpastes for both baseline and intervention phases. The toothbrushes were collected after two weeks for microbial analysis in both phases. The data were analysed and compared using appropriate statistical analysis. On comparing pre- and post-intervention, S. mutans colony counts, a highly significant (P < 0.001) difference was observed in all the groups. Differences of 77.74 colony forming units (CFU) in tea tree oil group, 102.87 CFU in garlic group, 68.13 CFU in chlorhexidine group, 82.47 CFU in cetylpyridinium group and 42.67 CFU in UV toothbrush sanitizer group were observed. Garlic group showed the highest reduction (100%) whereas UV toothbrush sanitizer group showed the least reduction (47.4%) in S. mutans colonies. The antimicrobial agents used in this study effectively reduced the S. mutans counts and hence can be considered as toothbrush disinfectants to prevent dental caries. The 3% garlic was the most effective among the antimicrobial agents.
Rothenberger, Jens; Krauss, Sabrina; Tschumi, Christian; Rahmanian-Schwarz, Afshin; Schaller, Hans-Eberhard; Held, Manuel
Antiseptics are indispensable for wound management and should focus not only on the efficacy in reducing the bacterial burden but also on how much they interfere in wound healing. In this study, the authors analyzed the direct effect of topical antiseptic agents on the microcirculation of intact human skin. The perfusion dynamics were assessed before, and 10 minutes after, the volunteers' fingers of the right hand (n = 20) were immersed in the following solutions - octenidine dihydrochloride, polyhexanide, tea tree oil, and saline solution. The authors used the Oxygen to See (LEA Medizintechnik GmbH, Giessen, Germany) diagnostic device for noninvasive determination of oxygen supply in microcirculation of blood perfused tissues, which combines a laser light to determine blood flow, as well as white light to determine hemoglobin oxygenation and the relative amount of hemoglobin. Tea tree oil (÷19.0%) (B. Braun Melsungen AG, Melsungen, Germany) and polyhexanide (÷12.4%) (Lavanid, Serag Wiessner GmbH, Naila, Germany) caused a significant increase in blood flow compared to the negative control (-25.6%). Octenidine (Octenisept, Schülke & Mayr GmbH, Norderstedt, Germany) showed a nonsignificant trend towards an increase in blood flow (÷7.2%). There were alterations in the values of hemoglobin oxygenation and the relative amount of hemoglobin, but these were not significant. Perfusion is an important factor for wound healing. Therefore, it might be advantageous if antiseptic agents would increase blood flow. Tea tree oil and polyhexanide have a positive effect on skin blood flow and can therefore be used especially in critically perfused wounds, provided the adverse reactions and the antimicrobial efficacy are comparable.
Smith, A C; Wood, C L; McQuerry, K J; Bewley, J M
Copper sulfate is the industry gold standard footbath ingredient for controlling dairy cow digital dermatitis. However, when used footbath solutions are deposited on soil, high levels of copper in the soil may result, which can have toxic and negative effects on plant growth. An alternative to copper sulfate is Provita Hoofsure Endurance (Provita Eurotech Ltd., Omagh, UK), which is a biodegradable solution containing organic acids, tea tree oil, and wetting agents. The objective of this study was to quantify changes in digital dermatitis frequency when using Provita Hoofsure Endurance and copper sulfate in a split footbath in 3 commercial dairy herds. This study was conducted from January 5, 2012, to March 19, 2012, in 3 commercial Kentucky dairies with 120, 170, and 200 milking Holstein cows. None of the herds was using a footbath for digital dermatitis control before the study. Footbath solutions were delivered using a split footbath. During the study, a 3% Hoofsure Endurance solution for the left hooves and a 5% copper sulfate solution for the right hooves was used. Digital dermatitis was scored every 3wk using the M0 to M4 system, where M0=a claw free of signs of digital dermatitis; M1=a lesion <2cm that is not painful; M2=the ulcerative stage, with lesion diameter of >2cm, and painful to the touch; M3=the healing stage and covered by a scab; and M4=the chronic stage and characterized by dyskeratosis or proliferation of the surface that is generally not painful. McNemar's test statistic suggested that a statistically significant difference existed in the proportions of M1 and M2 lesions between the beginning and end of the study for both treatments. This indicates that each solution was effective in decreasing the proportion of M1 or M2 lesions from baseline to the last time point. A chi-square test calculated using PROC FREQUENCY of SAS (SAS Institute Inc., Cary, NC) indicated that no statistically significant relationship existed between the treatments among
Inouye, Shigeharu; Nishiyama, Yayoi; Uchida, Katsuhisa; Hasumi, Yayoi; Yamaguchi, Hideyo; Abe, Shigeru
The vapor activity of six essential oils against a Trichophyton mentagrophytes was examined using a closed box. The antifungal activity was determined from colony size, which was correlated with the inoculum size. As judged from the minimum inhibitory dose and the minimum fungicidal dose determined after vapor exposure for 24 h, the vapor activity of the six essential oils was ranked in the following order: oregano > clove, perilla > geranium, lavender, tea tree. The vapors of oregano, perilla, tea tree, and lavender oils killed the mycelia by short exposure, for 3 h, but the vapors of clove and geranium oils were only active after overnight exposure. The vapor of oregano and other oils induced lysis of the mycelia. Morphological examination by scanning electron microscope (SEM) revealed that the cell membrane and cell wall were damaged in a dose- and time-dependent manner by the action of oregano vapor, causing rupture and peeling of the cell wall, with small bulges coming from the cell membrane. The vapor activity increased after 24 h, but mycelial accumulation of the active oil constituents was maximized around 15 h, and then decreased in parallel with the decrease of vapor concentration. This suggested that the active constituent accumulated on the fungal cells around 15 h caused irreversible damage, which eventually led to cellular death.
Cross, Sheree E; Russell, Michael; Southwell, Ian; Roberts, Michael S
The safety of topical application of Australian tea tree Oil (TTO) is confounded by a lack of transdermal penetration data, which adequately informs opinions and recommendations. In this study we applied TTO in its pure form and as a 20% solution in ethanol in vitro to human epidermal membranes from three different donors, mounted in horizontal Franz-type diffusion cells, using normal 'in use' dosing conditions (10 mg/cm2). In addition, we examined the effect of partially occluding the application site on the penetration of TTO components. Our data showed that only a small quantity of TTO components, 1.1-1.9% and 2-4% of the applied amount following application of a 20% TTO solution and pure TTO, respectively, penetrated into or through human epidermis. The largest TTO component penetrating the skin was terpinen-4-ol. Following partial occlusion of the application site, the penetration of terpinen-4-ol increased to approximately 7% of the applied TTO. Measurement of the rate of evaporation of tea tree oil from filter paper (7.4 mg/cm2) showed that 98% of the oil evaporated in 4 hours. Overall, it is apparent that the penetration of TTO components through human skin is limited.
Goode, T. W.
The planning and development phases of Tea Tree Gully College in South Australia and stage 1 of the design and construction of Joondalup Campus of North Metropolitan College in Western Australia were examined in two detailed case studies. Both are colleges of Technical and Further Education (TAFE). Strategic planning processes emerged as the most…
Goode, T. W.
The planning and development phases of Tea Tree Gully College in South Australia and stage 1 of the design and construction of Joondalup Campus of North Metropolitan College in Western Australia were examined in two detailed case studies. Both are colleges of Technical and Further Education (TAFE). Strategic planning processes emerged as the most…
Casiraghi, Antonella; Minghetti, Paola; Cilurzo, Francesco; Selmin, Francesca; Gambaro, Veniero; Montanari, Luisa
This work aimed to evaluate the effect induced by excipients conventionally used for topical dosage forms, namely isopropyl myristate (IPM) or oleic acid (OA) or polyethylene glycol 400 (PEG400) or Transcutol (TR), on the human skin permeability of terpinen-4-ol (T4OL) contained in the pure Tea tree oil. The effect of such excipients was determined by evaluating the absorption of T4OL using human epidermis and the perturbation of the organization of stratum corneum by ATR-FTIR. Among the tested excipients OA enhanced the absorption of T4OL by perturbing the stratum corneum lipid barrier. Other excipients caused a weak enhancement effect and their use should be carefully monitored.
Comin, Vanessa M; Lopes, Leonardo Q S; Quatrin, Priscilla M; de Souza, Márcia E; Bonez, Pauline C; Pintos, Francieli G; Raffin, Renata P; Vaucher, Rodrigo de A; Martinez, Diego S T; Santos, Roberto C V
The Pseudomonas aeruginosa is a gram-negative bacillus and frequent cause of infection. This microorganism is resistant intrinsically to various drugs. The P. aeruginosa is associated with the biofilm formation, which causes worsen the prognosis and difficulty the treatment. The influence of Melaleuca alternifolia oil or "tree of tee" oil (TTO) and TTO nanoparticles on adhesion of P. aeruginosa in buccal epithelial cells was investigated. Also was determined the antimicrobial and antibiofilm activity against this microorganism. The TTO nanoparticles were produced by deposition of preformed polymer and the physic-chemical properties of nanoparticles were measured by electrophoresis and dynamic light scattering. The characterization of nanoparticle showed acceptable values for diameter and zeta potential. The evaluation of antimicrobial and antibiofilm activity against P. aeruginosa PAO1 was performed by microdilution indicating the minimal inhibitory concentration, and the potential antibiofilm. It was verified the action on virulence factors such the motility, besides the influence on adhesion in buccal epithelial cells. Both oil and nanoparticles showed a decrease in adhesion of microorganisms to buccal cells, decrease of biofilm and interfering on P. aeruginosa PAO1 motility. The nanostructuration of TTO, shows be a viable alternative against formed biofilm microorganisms.
Kothiwale, Shaila V.; Patwardhan, Vivek; Gandhi, Megha; Sohoni, Rahul; Kumar, Ajay
Background: The relatively safe nature and cost-effectiveness of herbal extracts have led to a resurgent interest in their utility as therapeutic agents. Therefore, this prospective, double-blind, randomly controlled clinical trial was designed to compare the antiplaque and antigingivitis effects of newly formulated mouthrinse containing tea tree oil (TTO), clove, and basil with those of commercially available essential oil (EO) mouthrinse. Materials and Methods: Forty patients were selected for a 21-day study period and randomly divided into two groups. The test group patients were given newly formulated herbal mouthrinse and the control group patients were given commercially available EO mouthrinse. The Plaque Index (PI), Gingival Index (GI), and Papillary Marginal Attachment (PMA) Index were recorded at baseline, 14 days, and 21 days. The microbial colony forming units (CFU) were assessed at baseline and 21 days. Results: Test group patients using herbal mouthrinse showed significant improvement in GI (0.16), PI (0.57), and PMA (0.02) scores. These improvements were comparable to those achieved with commercially available EO mouthrinse. However, the aerobic and anaerobic CFU of microbiota were reduced with the herbal mouthrinse (P = 0.0000). Conclusion: The newly formulated herbal mouthrinse and commercially available mouthrinse were beneficial clinically as antiplaque and antigingivitis agents. Newly formulated mouthrinses showed significant reduction in microbial CFU at 21 days. So, our findings support the regular use of herbal mouthrinse as an antiplaque, antigingivitis, and antimicrobial rinse for better efficacy. PMID:25024544
Bagchi, Biswajoy; Banerjee, Somtirtha; Kool, Arpan; Thakur, Pradip; Bhandary, Suman; Hoque, Nur Amin; Das, Sukhen
A biocompatible poly(vinylidene) difluoride (PVDF) based film has been prepared by in situ precipitation of calcium phosphate precursors. Such films were surface absorbed with two essential oils namely eucalyptus and tea tree oil. Physico-chemical characterization of the composite film revealed excellent stability of the film with 10% loading of oils in the PVDF matrix. XRD, FTIR and FESEM measurements confirmed the presence of hydroxyapatite and octacalcium phosphate in the PVDF matrix which showed predominantly β phase. Strong bactericidal activity was observed with very low minimum bactericidal concentration (MBC) values on both E. coli and S. aureus. The composite films also resisted biofilm formation as observed by FESEM. The release of essential oils from the film showed an initial burst followed by a very slow release over a period of 24 hours. Antibacterial action of the film was found to be primarily due to the action of essential oils which resulted in leakage of vital fluids from the microorganisms. Both necrotic and apoptotic morphologies were observed in bacterial cells. Biocompatibility studies with the composite films showed negligible cytotoxicity to mouse mesenchymal and myoblast cells at MBC concentration.
Kothiwale, Shaila V; Patwardhan, Vivek; Gandhi, Megha; Sohoni, Rahul; Kumar, Ajay
The relatively safe nature and cost-effectiveness of herbal extracts have led to a resurgent interest in their utility as therapeutic agents. Therefore, this prospective, double-blind, randomly controlled clinical trial was designed to compare the antiplaque and antigingivitis effects of newly formulated mouthrinse containing tea tree oil (TTO), clove, and basil with those of commercially available essential oil (EO) mouthrinse. Forty patients were selected for a 21-day study period and randomly divided into two groups. The test group patients were given newly formulated herbal mouthrinse and the control group patients were given commercially available EO mouthrinse. The Plaque Index (PI), Gingival Index (GI), and Papillary Marginal Attachment (PMA) Index were recorded at baseline, 14 days, and 21 days. The microbial colony forming units (CFU) were assessed at baseline and 21 days. Test group patients using herbal mouthrinse showed significant improvement in GI (0.16), PI (0.57), and PMA (0.02) scores. These improvements were comparable to those achieved with commercially available EO mouthrinse. However, the aerobic and anaerobic CFU of microbiota were reduced with the herbal mouthrinse (P = 0.0000). The newly formulated herbal mouthrinse and commercially available mouthrinse were beneficial clinically as antiplaque and antigingivitis agents. Newly formulated mouthrinses showed significant reduction in microbial CFU at 21 days. So, our findings support the regular use of herbal mouthrinse as an antiplaque, antigingivitis, and antimicrobial rinse for better efficacy.
Wang, Mei; Zhao, Jianping; Avula, Bharathi; Wang, Yan-Hong; Chittiboyina, Amar G; Parcher, Jon F; Khan, Ikhlas A
GC/MS, chiral GC/MS, and chemometric techniques were used to evaluate a large set (n=104) of tea tree oils (TTO) and commercial products purported to contain TTO. Twenty terpenoids were determined in each sample and compared with the standards specified by ISO-4730-2004. Several of the oil samples that were ISO compliant when distilled did not meet the ISO standards in this study primarily due to the presence of excessive p-cymene and/or depletion of terpinenes. Forty-nine percent of the commercial products did not meet the ISO specifications. Four terpenes, viz., α-pinene, limonene, terpinen-4-ol, and α-terpineol, present in TTOs with the (+)-isomer predominant were measured by chiral GC/MS. The results clearly indicated that 28 commercial products contained excessive (+)-isomer or contained the (+)-isomer in concentrations below the norm. Of the 28 outliers, 7 met the ISO standards. There was a substantial subset of commercial products that met ISO standards but displayed unusual enantiomeric+/-ratios. A class predictive model based on the oils that met ISO standards was constructed. The outliers identified by the class predictive model coincided with the samples that displayed an abnormal chiral ratio. Thus, chiral and chemometric analyses could be used to confirm the identification of abnormal commercial products including those that met all of the ISO standards.
Pérez-Limiñana, María Ángeles; Payá-Nohales, Federico J; Arán-Ais, Francisca; Orgilés-Barceló, César
The aim of this study was to develop footwear materials with antimicrobial properties using microencapsulated Tea Tree oil (TTO) as a natural biocide. For that purpose, gelatine-carboxymethylcellulose based microcapsules containing TTO were synthesised by a complex coacervation process. Furthermore, the influence of the gelatine (G)/sodium carboxymethylmethyl cellulose (CMC) ratio (G/C) on the microcapsule properties, as well as in the microencapsulation oil efficiency, was evaluated. The microcapsules were characterised by different experimental techniques and applied to footwear materials (leather and textile) to evaluate their performance. The microcapsule durability under different conditions, such as rubbing and ironing, was analysed in order to simulate shoe manufacturing and shoe wearing. The properties of the microcapsules obtained by complex coacervation, using gelatine and sodium carboxymethylcellulose as shell-forming polymers, are determined by the ratio between those two polymers (G/C). The results obtained showed a notable effect of G/C ratio on the formation of the coacervate during the synthesis process and also on the encapsulation efficiency of the antimicrobial oil, with the optimal value for the G/C ratio being around 10.
This is a thematic lesson plan for young learners about palm trees and the importance of taking care of them. The two part lesson teaches listening, reading and speaking skills. The lesson includes parts of a tree; the modal auxiliary, can; dialogues and a role play activity.
Messager, S; Hammer, K A; Carson, C F; Riley, T V
The efficacy of formulations containing tea tree oil (TTO) has been assessed in vitro in previous studies. Products that passed the European suspension test guidelines were investigated further in this study, in vivo with volunteers using the European handwashing method (EN 1499) and ex vivo using freshly excised human skin samples. The activity of 5% TTO in 0.001% Tween 80, in a hygienic skin wash (HSW) and in an alcoholic hygienic skin wash (AHSW) was investigated and compared with that of a non-medicated soft soap (SS, control). These formulations were assessed against Escherichia coli K12 as recommended by the European standard. In-vivo results showed that 5% TTO in Tween 80 and the AHSW were significantly more active than the SS after 1 min of handwashing. When assessed ex vivo, these two products were also significantly more active than the reference soap after 1 min of rubbing. Both methods showed that 5% TTO in Tween 80 was generally, although not always, more active than a handwash formulation, and that the AHSW was generally more active than the HSW, although this difference was not significant. The formulations tested, as well as the SS, were more active when assessed in vivo than ex-vivo against E. coli, although only the SS and the HSW were significantly more active in vivo. There appeared to be a pattern in the comparison between ex vivo and in vivo results. The antiseptics tested were, on average, 1.28+/-0.06 times more active when assessed in-vivo than when assessed ex vivo. Nevertheless, the main outcome of the European handwashing method is for the formulation tested to be significantly more active than the SS; both 5% TTO in Tween 80 and the AHSW achieved this both in-vivo and ex-vivo. TTO in Tween 80 and in formulations met the European in-vivo method requirements.
An ex vivo, assessor blind, randomised, parallel group, comparative efficacy trial of the ovicidal activity of three pediculicides after a single application - melaleuca oil and lavender oil, eucalyptus oil and lemon tea tree oil, and a "suffocation" pediculicide
Background There are two components to the clinical efficacy of pediculicides: (i) efficacy against the crawling-stages (lousicidal efficacy); and (ii) efficacy against the eggs (ovicidal efficacy). Lousicidal efficacy and ovicidal efficacy are confounded in clinical trials. Here we report on a trial that was specially designed to rank the clinical ovicidal efficacy of pediculicides. Eggs were collected, pre-treatment and post-treatment, from subjects with different types of hair, different coloured hair and hair of different length. Method Subjects with at least 20 live eggs of Pediculus capitis (head lice) were randomised to one of three treatment-groups: a melaleuca oil (commonly called tea tree oil) and lavender oil pediculicide (TTO/LO); a eucalyptus oil and lemon tea tree oil pediculicide (EO/LTTO); or a "suffocation" pediculicide. Pre-treatment: 10 to 22 live eggs were taken from the head by cutting the single hair with the live egg attached, before the treatment (total of 1,062 eggs). Treatment: The subjects then received a single treatment of one of the three pediculicides, according to the manufacturers' instructions. Post-treatment: 10 to 41 treated live eggs were taken from the head by cutting the single hair with the egg attached (total of 1,183 eggs). Eggs were incubated for 14 days. The proportion of eggs that had hatched after 14 days in the pre-treatment group was compared with the proportion of eggs that hatched in the post-treatment group. The primary outcome measure was % ovicidal efficacy for each of the three pediculicides. Results 722 subjects were examined for the presence of eggs of head lice. 92 of these subjects were recruited and randomly assigned to: the "suffocation" pediculicide (n = 31); the melaleuca oil and lavender oil pediculicide (n = 31); and the eucalyptus oil and lemon tea tree oil pediculicide (n = 30 subjects). The group treated with eucalyptus oil and lemon tea tree oil had an ovicidal efficacy of 3.3% (SD 16%) whereas the
An ex vivo, assessor blind, randomised, parallel group, comparative efficacy trial of the ovicidal activity of three pediculicides after a single application--melaleuca oil and lavender oil, eucalyptus oil and lemon tea tree oil, and a "suffocation" pediculicide.
Barker, Stephen C; Altman, Phillip M
There are two components to the clinical efficacy of pediculicides: (i) efficacy against the crawling-stages (lousicidal efficacy); and (ii) efficacy against the eggs (ovicidal efficacy). Lousicidal efficacy and ovicidal efficacy are confounded in clinical trials. Here we report on a trial that was specially designed to rank the clinical ovicidal efficacy of pediculicides. Eggs were collected, pre-treatment and post-treatment, from subjects with different types of hair, different coloured hair and hair of different length. Subjects with at least 20 live eggs of Pediculus capitis (head lice) were randomised to one of three treatment-groups: a melaleuca oil (commonly called tea tree oil) and lavender oil pediculicide (TTO/LO); a eucalyptus oil and lemon tea tree oil pediculicide (EO/LTTO); or a "suffocation" pediculicide. Pre-treatment: 10 to 22 live eggs were taken from the head by cutting the single hair with the live egg attached, before the treatment (total of 1,062 eggs). The subjects then received a single treatment of one of the three pediculicides, according to the manufacturers' instructions. Post-treatment: 10 to 41 treated live eggs were taken from the head by cutting the single hair with the egg attached (total of 1,183 eggs). Eggs were incubated for 14 days. The proportion of eggs that had hatched after 14 days in the pre-treatment group was compared with the proportion of eggs that hatched in the post-treatment group. The primary outcome measure was % ovicidal efficacy for each of the three pediculicides. 722 subjects were examined for the presence of eggs of head lice. 92 of these subjects were recruited and randomly assigned to: the "suffocation" pediculicide (n = 31); the melaleuca oil and lavender oil pediculicide (n = 31); and the eucalyptus oil and lemon tea tree oil pediculicide (n = 30 subjects). The group treated with eucalyptus oil and lemon tea tree oil had an ovicidal efficacy of 3.3% (SD 16%) whereas the group treated with melaleuca oil and
An algebraic formalism, developed with V. Glaser and R. Stora for the study of the generalized retarded functions of quantum field theory, is used to prove a factorization theorem which provides a complete description of the generalized retarded functions associated with any tree graph. Integrating over the variables associated to internal vertices to obtain the perturbative generalized retarded functions for interacting fields arising from such graphs is shown to be possible for a large category of space-times.
Young, Darrell D.
Describes plants commonly found in residential areas that can be used for making tea: chicory, chickweed, red clover, goldenrod, gill-over-the-ground, pineapple weed, plantain, self-heal, sheep sorrel, and wild strawberry. Includes proper plant name, areas where the plant grows, identifying plant features, what part is used in making tea, and tea…
Young, Darrell D.
Describes plants commonly found in residential areas that can be used for making tea: chicory, chickweed, red clover, goldenrod, gill-over-the-ground, pineapple weed, plantain, self-heal, sheep sorrel, and wild strawberry. Includes proper plant name, areas where the plant grows, identifying plant features, what part is used in making tea, and tea…
Ramage, Gordon; Milligan, Steven; Lappin, David F; Sherry, Leighann; Sweeney, Petrina; Williams, Craig; Bagg, Jeremy; Culshaw, Shauna
Candida albicans forms oral biofilms that cause disease and are difficult to treat with conventional antifungal agents. Tea tree oil (TTO) is a natural compound with reported antimicrobial and immunomodulatory activities. The aims of the study were to evaluate the antifungal efficacy of TTO and key derivatives against C. albicans biofilms, to assess the toxicological effects of TTO on a clinically relevant oral cell line, and to investigate its impact on inflammation. TTO and its derivatives were examined against 100 clinical strains of C. albicans. Planktonic minimum inhibitory concentrations (MICs) were determined using the CLSI M-27A broth microdilution method. Sessile MICs were determined using an XTT reduction assay. Inhibition, time-kill, and mode of action studies were performed. OKF6-TERT2 epithelial cells were used for cytotoxicity and cytokine expression assays. Planktonic C. albicans isolates were susceptible to TTO, terpinen-4-ol (T-4-ol), and α-terpineol, with an MIC(50) of 0.5, 0.25, and 0.25%, respectively. These three compounds also displayed potent activity against the 69 biofilm-forming strains, of which T-4-ol and α-terpineol displayed rapid kill kinetics. For all three compounds, 1 × MIC(50) effectively inhibited biofilm growth when C. albicans were treated at 0, 1, and 2 h post adhesion. By scanning electron microscopy analysis and PI uptake, TTO and derivative components were shown to be cell membrane active. TTO and T-4-ol were cytotoxic at 1 × MIC(50), whereas at 0.5 × MIC(50) T-4-ol displayed no significant toxicity. Transcript and protein analysis showed a reduction of IL-8 when treated with TTO and T-4-ol. These data provide further in vitro evidence that TTO and its derivative components, specifically T-4-ol, exhibit strong antimicrobial properties against fungal biofilms. T-4-ol has safety advantages over the complete essential oil and may be suitable for prophylaxis and treatment of established oropharyngeal
Ramage, Gordon; Milligan, Steven; Lappin, David F.; Sherry, Leighann; Sweeney, Petrina; Williams, Craig; Bagg, Jeremy; Culshaw, Shauna
Candida albicans forms oral biofilms that cause disease and are difficult to treat with conventional antifungal agents. Tea tree oil (TTO) is a natural compound with reported antimicrobial and immunomodulatory activities. The aims of the study were to evaluate the antifungal efficacy of TTO and key derivatives against C. albicans biofilms, to assess the toxicological effects of TTO on a clinically relevant oral cell line, and to investigate its impact on inflammation. TTO and its derivatives were examined against 100 clinical strains of C. albicans. Planktonic minimum inhibitory concentrations (MICs) were determined using the CLSI M-27A broth microdilution method. Sessile MICs were determined using an XTT reduction assay. Inhibition, time-kill, and mode of action studies were performed. OKF6-TERT2 epithelial cells were used for cytotoxicity and cytokine expression assays. Planktonic C. albicans isolates were susceptible to TTO, terpinen-4-ol (T-4-ol), and α-terpineol, with an MIC50 of 0.5, 0.25, and 0.25%, respectively. These three compounds also displayed potent activity against the 69 biofilm-forming strains, of which T-4-ol and α-terpineol displayed rapid kill kinetics. For all three compounds, 1 × MIC50 effectively inhibited biofilm growth when C. albicans were treated at 0, 1, and 2 h post adhesion. By scanning electron microscopy analysis and PI uptake, TTO and derivative components were shown to be cell membrane active. TTO and T-4-ol were cytotoxic at 1 × MIC50, whereas at 0.5 × MIC50 T-4-ol displayed no significant toxicity. Transcript and protein analysis showed a reduction of IL-8 when treated with TTO and T-4-ol. These data provide further in vitro evidence that TTO and its derivative components, specifically T-4-ol, exhibit strong antimicrobial properties against fungal biofilms. T-4-ol has safety advantages over the complete essential oil and may be suitable for prophylaxis and treatment of established oropharyngeal candidosis. A
Santamaria, Milton; Petermann, Klodyne Dayana; Vedovello, Silvia Amélia Scudeler; Degan, Viviane; Lucato, Adriana; Franzini, Cristina Maria
The aim of this study was to evaluate the antimicrobial effect and sensorial analysis of the gel developed with the essential oil of Melaleuca alternifolia. Thirty-four volunteers, divided into 2 groups, were monitored for 4 weeks. Initially, clinical biofilm (plaque index) and saliva samples (bacteria count) were collected, from which the standard values for each patient were obtained. For 7 days, group 1 used the melaleuca gel (Petite Marie/All Chemistry, São Paulo, Brazil), and group 2 used Colgate Total (S.B. Campo, São Paulo, Brazil). After 7 days, the plaque index was performed again, as well as the bacteria count and the sensorial analysis (appearance, color, odor, brightness, viscosity, and first taste sensation). The volunteers were instructed to return to their usual dental hygiene habits for 15 days. After this, group 1 started using Colgate Total, and group 2 started using the melaleuca gel, with the same evaluation procedures as the first week. The data were analyzed statistically with a significance level of 5%. In the bacteria count and clinical disclosure, the melaleuca gel was more effective in decreasing the dental biofilm and the numbers of bacteria colonies. According to the data from the sensory evaluation, Colgate Total (the control) showed better results regarding flavor and first sensation (P <0.05). We concluded that melaleuca gel is efficient in bacteria control but needs improvement in taste and first sensation.
... But this does not seem to occur in humans.Flutamide (Eulexin)The body breaks down flutamide (Eulexin) ... much medicine the body absorbs. To avoid this interaction, avoid black tea 1 hour before and 2 ...
Wang, Chen; Lv, Shidong; Wu, Yuanshuang; Gao, Xuemei; Li, Jiangbing; Zhang, Wenrui; Meng, Qingxiong
Consistent aroma characteristics are important for tea products. However, understanding the formation of tea aroma flavor and correspondingly proposing applicable protocols to control tea quality and consistency remain major challenges. Oolong tea is one of the most popular teas with a distinct flavor. Generally, oolong tea is processed with the leaves of tea trees belonging to different subspecies and grown in significantly different regions. In this study, Yunnan and Fujian oolong teas, green tea, black tea, and Pu-erh tea were collected from major tea estates across China. Their sensory evaluation, main water-soluble and volatile compounds were identified and measured. The sensory evaluation, total polysaccharide, caffeine, and catechin content of Yunnan oolong tea was found to be different from that of Fujian oolong tea, a result suggesting that the kinds of tea leaves used in Yunnan and Fujian oolong teas were naturally different. However, according to their aroma compounds, principal component analysis (PCA) and cluster analysis (CA) of the volatile compounds showed that the two types of oolong teas were similar and cannot be clearly distinguished from each other; they are also different from green, black, and Pu-erh teas, a result indicating that the same oolong tea processing technology applied to different tea leaves results in consistent aroma characteristics. The PCA analysis results also indicated that benzylalcohol, indole, safranal, linalool oxides, β-ionone, and hexadecanoic acid methyl ester highly contributed to the distinct aroma of oolong tea compared with the other three types of teas. This study proved that the use of the same processing technology on two kinds of tea leaves resulted in a highly consistent tea aroma.
Joksimovic, N; Spasovski, G; Joksimovic, V; Andreevski, V; Zuccari, C; Omini, C F
Topical formulations are widely used in anti-haemorrhoidal treatment, but often lacking controlled clinical trials. Here, we report the results from a controlled clinical trial performed with a new gel medical device (Proctoial) containing hyaluronic acid with tea tree oil and methyl-sulfonyl-methane as major components. The total number of 36 haemorrhoidal patients (grade 1-3) was enrolled in a double-blind, placebo-controlled clinical trial and divided into 2 equal parallel groups. The anal pain, pain during defecation, visible bleeding, pruritus and irritation/inflammation were recorded before and after 14-day treatment using a visual analogue scale both by the investigators and by the patients. Safety and tolerability of the treatments were also recorded. The new gel medical device statistically significantly reduced all the symptoms after the treatment compared to placebo. The results indicated also a very good tolerability and safety of the treatments.
Valladão, G M R; Gallani, S U; Ikefuti, C V; da Cruz, C; Levy-Pereira, N; Rodrigues, M V N; Pilarski, F
In vitro effect of the Melaleuca alternifolia, Lavandula angustifolia and Mentha piperita essential oils (EOs) against Ichthyophthirius multifiliis and in vivo effect of M. alternifolia for treating ichthyophthiriasis in one of the most important South American fish, Piaractus mesopotamicus (Holmberg), were evaluated. The in vitro test consisted of three EOs, each at concentrations of 57 μL L(-1) , 114 μL L (-1) , 227 μL L(-1) and 455 μL L (-1) , which were assessed once an hour for 4 h in microtitre plates (96 wells). The in vitro results demonstrated that all tested EOs showed a cytotoxic effect against I. multifiliis compared to control groups (P < 0.05). The in vivo treatment for white spot disease was performed in a bath for 2 h day(-1) for 5 days using the M. alternifolia EO (50 μL L (-1) ). In this study, 53.33% of the fish severely infected by I. multifiliis survived after the treatment with M. alternifolia (50 μL L (-1) ) and the parasitological analysis has shown an efficacy of nearly 100% in the skin and gills, while all the fish in the control group died. Furthermore, the potential positive effect of M. alternifolia EO against two emergent opportunistic bacteria in South America Edwardsiella tarda and Citrobacter freundii was discussed. © 2016 John Wiley & Sons Ltd.
Shah, Gagan; Baghel, Uttam Singh
Melaleuca alternifolia (Myrtaceae) is a well-known, commonly used, tall shrub plant in Ayurvedic medicine. Traditionally, it is used for its antimicrobial potential to treat cutaneous infections. No attempts have been made regarding pharmacognostic investigation of the plant till date. So, the present study was aimed to establish standards with the help of different pharmacognostic parameters. Various pharmacognostic parameters (morphological, microscopic, physicochemical evaluations and preliminary phytochemical screening) were studied along with fluorescent and thin layer chromatographic analysis of the extract. Morphologically Melaleuca alternifolia is a shrub having height of 7 m with layered and papery bark. Leaves have an arranged pattern, petiole is 1 mm in length; linear-acute with dimensions of 10-35 mm x 1 mm. Organoleptic features shows that leaves have characteristic odour and astringent taste. The transverse section of the leaf reveals the existence of epidermal layers, mesophyll tissues, vascular bundles and secretory cavities. The stomata are anomocytic and leaf constants such as stomatal number is 180-200-225, stomatal index is 3.8-4.4-5.9, vein islet number is 18.68 (average), veinlet termination number 20.3 (average) and palisade ratio is 5.5-6.4-6.9. The results of phytochemical screening showed the occurrence of different phytoconstituents (flavonoids, phenolic tannins, phytosterol and terpenoids). The present study evaluated various pharmacognostic parameters which will help in quality control (standardization) of Melaleuca alternifolia leaves in crude form, in herbal formulation and also aid in the preparation of an herbal monograph for the species.
Manteiga, R; Park, D L; Ali, S S
Plants have been used for medicinal purposes for centuries. Health-oriented individuals are turning to herbal teas as alternatives to caffeinated beverages such as coffee, tea, and cocoa and for low-caloric supplements. The popularity of herbal tea consumption has increased significantly during the past two decades in the U.S. Hundreds of different teas made up of varied mixtures of roots, leaves, seeds, barks, or other parts of shrubs, vines, or trees are sold in health food stores. Although chemists have been characterizing toxic plant constituents for over 100 years, toxicological studies of herbal teas have been limited and, therefore, the safety of many of these products is unknown. Plants synthesize secondary metabolites that are not essential in the production of energy and whose role may be in the defense mechanisms as plant toxins to their interactions with other plants, herbivores, and parasites. Pyrrolizidine alkaloids (PAs) were among the first naturally occurring carcinogens identified in plant products, and their presence in herbal teas is a matter of public health significance. Some herbal tea mixtures and single-ingredient herbal teas have been analyzed for toxic/mutagenic potential by bioassay and chromatographic techniques. Numerous human and animal intoxications have been associated with naturally occurring components, including pyrrolizidine alkaloids, tannins, and safrole. Thus, the prevention of human exposure to carcinogens or mutagens present in herbal tea mixture extracts is crucial. Preparation of infusion drinks prepared from plants appears to concentrate biologically active compounds and is a major source of PA poisoning. The quantity and consumption over a long period of time is of major concern. It is recommended that widespread consumption of herbal infusions should be minimized until data on the levels and varieties of carcinogens, mutagens, and toxicants are made available.
GRAZIANO, Talita Signoreti; CALIL, Caroline Morini; SARTORATTO, Adilson; FRANCO, Gilson César Nobre; GROPPO, Francisco Carlos; COGO-MÜLLER, Karina
ABSTRACT Objective Halitosis can be caused by microorganisms that produce volatile sulphur compounds (VSCs), which colonize the surface of the tongue and subgingival sites. Studies have reported that the use of natural products can reduce the bacterial load and, consequently, the development of halitosis. The aim of this study was to evaluate the antimicrobial activity of the essential oil of Melaleuca alternifolia on the growth and volatile sulphur compound (VSC) production of oral bacteria compared with chlorhexidine. Material and Methods The effects of these substances were evaluated by the Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) in planktonic cultures of Porphyromonas gingivalis and Porphyromonas endodontalis. In addition, gas chromatography analyses were performed to measure the concentration of VSCs from bacterial cultures and to characterize M. alternifolia oil components. Results The MIC and MBC values were as follows: M. alternifolia - P. gingivalis (MIC and MBC=0.007%), P. endodontalis (MIC and MBC=0.007%=0.5%); chlorhexidine - P. gingivalis and P. endodontalis (MIC and MBC=1.5 mg/mL). M. alternifolia significantly reduced the growth and production of hydrogen sulfide (H2S) by P. gingivalis (p<0.05, ANOVA-Dunnet) and the H2S and methyl mercaptan (CH3SH) levels of P. endodontalis (p<0.05, ANOVA-Dunnet). Chlorhexidine reduced the growth of both microorganisms without altering the production of VSC in P. endodontalis. For P. gingivalis, the production of H2S and CH3SH decreased (p<0.05, ANOVA-Dunnet). Conclusion M. alternifolia can reduce bacterial growth and VSCs production and could be used as an alternative to chlorhexidine. PMID:28076463
Graziano, Talita Signoreti; Calil, Caroline Morini; Sartoratto, Adilson; Franco, Gilson César Nobre; Groppo, Francisco Carlos; Cogo-Müller, Karina
Halitosis can be caused by microorganisms that produce volatile sulphur compounds (VSCs), which colonize the surface of the tongue and subgingival sites. Studies have reported that the use of natural products can reduce the bacterial load and, consequently, the development of halitosis. The aim of this study was to evaluate the antimicrobial activity of the essential oil of Melaleuca alternifolia on the growth and volatile sulphur compound (VSC) production of oral bacteria compared with chlorhexidine. The effects of these substances were evaluated by the Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) in planktonic cultures of Porphyromonas gingivalis and Porphyromonas endodontalis. In addition, gas chromatography analyses were performed to measure the concentration of VSCs from bacterial cultures and to characterize M. alternifolia oil components. The MIC and MBC values were as follows: M. alternifolia - P. gingivalis (MIC and MBC=0.007%), P. endodontalis (MIC and MBC=0.007%=0.5%); chlorhexidine - P. gingivalis and P. endodontalis (MIC and MBC=1.5 mg/mL). M. alternifolia significantly reduced the growth and production of hydrogen sulfide (H2S) by P. gingivalis (p<0.05, ANOVA-Dunnet) and the H2S and methyl mercaptan (CH3SH) levels of P. endodontalis (p<0.05, ANOVA-Dunnet). Chlorhexidine reduced the growth of both microorganisms without altering the production of VSC in P. endodontalis. For P. gingivalis, the production of H2S and CH3SH decreased (p<0.05, ANOVA-Dunnet). M. alternifolia can reduce bacterial growth and VSCs production and could be used as an alternative to chlorhexidine.
A randomized controlled trial of tea tree oil (5%) body wash versus standard body wash to prevent colonization with methicillin-resistant Staphylococcus aureus (MRSA) in critically ill adults: research protocol.
Thompson, Gillian; Blackwood, Bronagh; McMullan, Ronan; Alderdice, Fiona A; Trinder, T John; Lavery, Gavin G; McAuley, Danny F
Over the past ten years MRSA has become endemic in hospitals and is associated with increased healthcare costs. Critically ill patients are most at risk, in part because of the number of invasive therapies that they require in the intensive care unit (ICU). Washing with 5% tea tree oil (TTO) has been shown to be effective in removing MRSA on the skin. However, to date, no trials have evaluated the potential of TTO body wash to prevent MRSA colonization or infection. In addition, detecting MRSA by usual culture methods is slow. A faster method using a PCR assay has been developed in the laboratory, but requires evaluation in a large number of patients. This study protocol describes the design of a multicentre, phase II/III prospective open-label randomized controlled clinical trial to evaluate whether a concentration of 5% TTO is effective in preventing MRSA colonization in comparison with a standard body wash (Johnsons Baby Softwash) in the ICU. In addition we will evaluate the cost-effectiveness of TTO body wash and assess the effectiveness of the PCR assay in detecting MRSA in critically ill patients. On admission to intensive care, swabs from the nose and groin will be taken to screen for MRSA as per current practice. Patients will be randomly assigned to be washed with the standard body wash or TTO body wash. On discharge from the unit, swabs will be taken again to identify whether there is a difference in MRSA colonization between the two groups. If TTO body wash is found to be effective, widespread implementation of such a simple colonization prevention tool has the potential to impact on patient outcomes, healthcare resource use and patient confidence both nationally and internationally.
In vitro activity of tea-tree oil against clinical skin isolates of meticillin-resistant and -sensitive Staphylococcus aureus and coagulase-negative staphylococci growing planktonically and as biofilms.
Brady, Aaron; Loughlin, Ryan; Gilpin, Deirdre; Kearney, Paddy; Tunney, Michael
The susceptibility of Staphylococcus aureus [meticillin-resistant (MRSA) and meticillin-sensitive (MSSA)] and coagulase-negative staphylococci (CoNS), which respectively form part of the transient and commensal skin flora, to tea-tree oil (TTO) was compared using broth microdilution and quantitative in vitro time-kill test methods. MRSA and MSSA isolates were significantly less susceptible than CoNS isolates, as measured by both MIC and minimum bactericidal concentration. A significant decrease in the mean viable count of all isolates in comparison with the control was seen at each time interval in time-kill assays. However, the only significant difference in the overall mean log10 reduction in viable count between the groups of isolates was between CoNS and MSSA at 3 h, with CoNS isolates demonstrating a significantly lower mean reduction. To provide a better simulation of in vivo conditions on the skin, where bacteria are reported to grow as microcolonies encased in glycocalyx, the bactericidal activity of TTO against isolates grown as biofilms was also compared. Biofilms formed by MSSA and MRSA isolates were completely eradicated following exposure to 5 % TTO for 1 h. In contrast, of the biofilms formed by the nine CoNS isolates tested, only five were completely killed, although a reduction in viable count was apparent for the other four isolates. These results suggest that TTO exerts a greater bactericidal activity against biofilm-grown MRSA and MSSA isolates than against some biofilm-grown CoNS isolates.
Tea tree oil (5%) body wash versus standard care (Johnson's Baby Softwash) to prevent colonization with methicillin-resistant Staphylococcus aureus in critically ill adults: a randomized controlled trial.
Blackwood, Bronagh; Thompson, Gillian; McMullan, Ronan; Stevenson, Michael; Riley, Thomas V; Alderdice, Fiona A; Trinder, T John; Lavery, Gavin G; McAuley, Danny F
To determine whether the daily use of 5% tea tree oil (TTO) body wash (Novabac 5% Skin Wash) compared with standard care [Johnson's Baby Softwash (JBS)] had a lower incidence of methicillin-resistant Staphylococcus aureus (MRSA) colonization. The study setting was two intensive care units (ICUs; mixed medical, surgical and trauma) in Northern Ireland between October 2007 and July 2009. The study population comprised 391 patients who were randomized to JBS or TTO body wash. This was a Phase 2/3, prospective, open-label, randomized, controlled trial. ISRCTN65190967. The primary outcome was new MRSA colonization during ICU stay. Secondary outcomes included the incidence of MRSA bacteraemia and maximum increase in sequential organ failure assessment score. A total of 445 patients were randomized to the study. After randomization, 54 patients were withdrawn; 30 because of a positive MRSA screen at study entry, 11 due to lack of consent, 11 were inappropriately randomized and 2 had adverse reactions. Thirty-nine (10%) patients developed new MRSA colonization (JBS n = 22, 11.2%; TTO body wash n = 17, 8.7%). The difference in percentage colonized (2.5%, 95% CI - 8.95 to 3.94; P = 0.50) was not significant. The mean maximum increase in sequential organ failure assessment score was not significant (JBS 1.44, SD 1.92; TTO body wash 1.28, SD 1.79; P = 0.85) and no study patients developed MRSA bacteraemia. Compared with JBS, TTO body wash cannot be recommended as an effective means of reducing MRSA colonization.
Comparison of clinical and histological effects between lactobacillus-fermented Chamaecyparis obtusa and tea tree oil for the treatment of acne: an eight-week double-blind randomized controlled split-face study.
Kwon, Hyuck Hoon; Yoon, Ji Young; Park, Seon Yong; Min, Seonguk; Suh, Dae Hun
Screening of natural compounds for the development of anti-acne therapeutic agents has been steadily required considering various side effects of acne medications. However, previous studies have mainly focused on experimental tests without clinical trials and histopathological analysis. To compare the clinical efficacy, safety and histopathological changes between Lactobacillus-fermented Chamaecyparis obtusa (LFCO) and existing tea tree oil (TTO). A total of 34 patients were instructed to apply 5% LFCO to the involved areas of a randomly allocated side and 5% TTO extract to the other side for 8 weeks in a double-blind split-face clinical trial. After 8 weeks, inflammatory acne lesions were reduced by 65.3% on the LFCO side and by 38.2% on the TTO side. LFCO was also superior to TTO in the onset time of efficacy (p < 0.05). The LFCO side further demonstrated improvement for non-inflammatory lesions (52.6%, p < 0.05), decreased size of sebaceous glands and sebum output reductions. Patients' subjective satisfaction was also higher without severe adverse reactions. Protein expressions of nuclear factor κB decreased earlier on the LFCO side, and those of interleukin-1α (IL-1α), IL-8, insulin-like growth factor 1 receptor and sterol regulatory element-binding protein 1 decreased subsequently. Ultra-performance liquid chromatography/high-resolution mass spectrometry further demonstrated that the contents of dihydroxybenzoic acid, taxifolin and quercetin were increased in LFCO after fermentation. LFCO treatment was rapid and effective for treating acne lesions compared to TTO. Histopathological findings correlated well with the clinical acne grade and treatment response. This novel natural compound appears to be effective and safe for acne treatment.
Long, Ping; Cui, Zhanhu; Wang, Yingli; Zhang, Chunhong; Zhang, Na; Li, Minhui; Xiao, Peigen
Non-Camellia tea is a part of the colorful Chinese tea culture, and is also widely used as beverage and medicine in folk for disease prevention and treatment. In this study, 37 samples were collected, including 33 kinds of non-Camellia teas and 4 kinds of teas (Camellia). Traditional functions of non-Camellia teas were investigated. Furthermore, non-Camellia teas of original plants were characterized and identified by molecular methods. Four candidate regions (rbcL, matK, ITS2, psbA-trnH) were amplified by polymerase chain reaction. In addition, DNA barcodes were used for the first time to discriminate the commercial non-Camellia tea and their adulterants, and to evaluate their safety. This study showed that BLASTN and the relevant phylogenetic tree are efficient tools for identification of the commercial non-Camellia tea and their adulterants. However, some sequences from original plants have not been found and there is a limitation of sequence number of original plants in GenBank. Submitting more original plant sequences to the GenBank will be helpful for evaluating the safety of non-Camellia teas. PMID:26579387
Fauziana, F.; Danoedoro, P.; Heru Murti, S.
Remote sensing has been utilized especially for agriculture yield estimation. Tea yield is effected by biology characteristic including crown density. The challenge of tea yield estimation uses multispectral remote sensing data is the presence of object beside tea. This mixed pixel problem can disturb spectrally to recognize tea tree, so it is necessary to use pixel approach. The aims of this research are (1) to determine fraction of tea and non-tea; (2) to estimate crown density percentage based on tea Normalized Difference Vegetation Index (NDVI); (3) to estimate tea yield based on crown density. SPOT-7 was utilized for this application. Linear Spectral Mixture Analysis (LSMA) has applied to determination fraction percentage each pixel. Each pure endmember was read the NDVI value. NDVI of tea tree has sensitivity with crown density. Counting tea NDVI was applied for NDVI mixed pixel. Linear regression analysis has applied for estimating crown density and tea yield. The results of this research are SPOT -7 which can recognize tea, tree shade, impervious and soil each pixel with accuracy 99,84%. Although it produced high accuracy, it has overestimate at certain tea estate because of the attendance of impervious. Regression analysis of crown density and NDVI showed coeffisien determination 52%. This model result 4-100% crown density percentage, where crown density 4-55% were located beside tea tree or pruned-tea block. Regression analysis of crown density and tea yield relation showed coeffisien determination 45%. This model produced 161,34-1296,8 kg/ha. Each this model resulted Root Mean Square Error (RMSE) 14,27% and 551,52 kg/ha.
Biva, Israt J; Ndi, Chi P; Griesser, Hans J; Semple, Susan J
For traditional medicinal purposes Aboriginal Australians have utilised numerous plant species, Eremophila alternifolia is among the most prominent. Traditionally, fresh leaves, leaf-infusions and handmade leaf-pastes have been used as both external and internal preparations to provide relief from a variety of conditions. Preparations of the species have been used to treat various infections of skin, eyes and throat including the treatment of septic wounds. These usages suggest that the plant contains antibacterial compounds; however, to date they have not been isolated and identified. The present study aimed to identify antibacterial compounds from this important traditionally recorded medicinal species. Bioassay-guided fractionation was used to isolate compounds from the crude leaf-extract. Antibacterial activity of pure compounds was assessed through broth microdilution method by determining both minimum inhibitory concentrations (MICs) and minimum bactericidal concentrations (MBCs). Structure elucidation was performed using spectroscopic techniques such as 1D and 2D nuclear magnetic resonance spectroscopy and high resolution mass spectrometry. Four compounds have been isolated from the leaf-extract; they include previously known flavanones [pinobanksin (1), pinobanksin-3-acetate (2) and pinobanksin-3-cinnamate (3)] and a serrulatane diterpene, 8-hydroxyserrulat-14-en-19-oic acid (4). While compound 4 had been found in other Eremophilas, flavanones 2 and 3 are identified for the first time from the genus Eremophila. The flavanone 3 is the most promising antibacterial compound with significant activity (10-20µM) against strains of the Gram-positive bacterium Staphylococcus aureus including methicillin resistant and biofilm forming strains. No activity was observed for any isolated compounds against the Gram-negative bacterium Escherichia coli. The antibacterial activity of the crude extract of E. alternifolia and of the isolated compounds against Gram
Evans, Bethany; Borowicz, Victoria
Holoparasites are nonphotosynthetic plants that acquire all resources from hosts. The holoparasite Cuscuta gronovii is native to much of the US with a broad host range including Verbesina alternifolia, an understory perennial. Both species grow in moderate to moist soils and occur in habitats that may experience prolonged or episodic drought. We applied the Wise-Abrahamson Limiting Resource Model (LRM) developed for plant-herbivore relations to examine the effects of pattern of drought stress on tolerance of V. alternifolia to parasitism by C. gronovii. Individual plants were assigned one of six treatments that were combinations of parasite (none or addition of parasite) and drought stress (well-watered, continuously-stressed, or pulse-stressed). After pulse-stressed plants had experienced two wet-dry cycles all plants were harvested. Parasitism strongly reduced both shoot and root mass and well-watered hosts exhibited the greatest decline, indicating reduced tolerance to parasitism when water was readily available. This is consistent with the LRM if parasitism limits photosynthates available to the host. However, parasitism increased allocation to shoot and this effect did not differ between well-watered and drought-stressed plants, indicating equal tolerance. This outcome is in accord with an alternative prediction of the LRM if hosts are not carbon limited. Total pot productivity was reduced by parasitism and drought stress, and this effect was greater for pulse-stressed than for continuously-stressed hosts. We discuss the applicability of the LRM for understanding the effects of drought on tolerance to parasitism. PMID:27137396
Anderson, Richard A; Polansky, Marilyn M
The most widely known health benefits of tea relate to the polyphenols as the principal active ingredients in protection against oxidative damage and in antibacterial, antiviral, anticarcinogenic, and antimutagenic activities, but polyphenols in tea may also increase insulin activity. The objective of this study was to determine the insulin-enhancing properties of tea and its components. Tea, as normally consumed, was shown to increase insulin activity >15-fold in vitro in an epididymal fat cell assay. Black, green, and oolong teas but not herbal teas, which are not teas in the traditional sense because they do not contain leaves of Camellia senensis, were all shown to increase insulin activity. High-performance liquid chromatography fractionation of tea extracts utilizing a Waters SymmetryPrep C18 column showed that the majority of the insulin-potentiating activity for green and oolong teas was due to epigallocatechin gallate. For black tea, the activity was present in several regions of the chromatogram corresponding to, in addition to epigallocatechin gallate, tannins, theaflavins, and other undefined compounds. Several known compounds found in tea were shown to enhance insulin with the greatest activity due to epigallocatechin gallate followed by epicatechin gallate, tannins, and theaflavins. Caffeine, catechin, and epicatechin displayed insignificant insulin-enhancing activities. Addition of lemon to the tea did not affect the insulin-potentiating activity. Addition of 5 g of 2% milk per cup decreased the insulin-potentiating activity one-third, and addition of 50 g of milk per cup decreased the insulin-potentiating activity approximately 90%. Nondairy creamers and soy milk also decreased the insulin-enhancing activity. These data demonstrate that tea contains in vitro insulin-enhancing activity and the predominant active ingredient is epigallocatechin gallate.
Ott, James R; Lampo, Margarita
Direct observations and analyses of selection occurring in natural populations are rare. The biology of the bruchid beetle,Acanthoscelides alboscutellatus, on its host plant,Ludwigia alternifolia, provides an anusual opportunity to study the process of selection on the morphology of an organism under field conditions.A. alboscutellatus larvae mature within the variably dehiscent fruit ofL. alternifolia. At eclosion, adults are confined within indehiscent fruit but are not confined within dehiscent fruit. Beetles can escape from indehiscent fruit only by forcing their bodies through the fruit's apical pore (a circular opening in the top of the fruit). Thus, during the eclosion stage of this beetle's life cycle the relationship between body size and differential fitness appears to be clearly defined.We examined entrapment ofA. alboscutellatus within indehiscentL. alternifolia fruit in a natural population. Only 8.8% of the beetles that attempted to escape were successful. Smaller beetles were trapped within a narrower range of pore diameters than were larger beetles; and trapped beetles had only limited abilities to enlarge fruit pore diameter. These data suggest (1) that escape from indehiscent fruit is regulated by the relationship between adult body diameter and fruit pore diameter and (2) that adult beetles may experience strong selection for small body diameter (size) within idehiscent fruit.
Tong, Mengmeng; Gao, Wanjun; Jiao, Weiting; Zhou, Jie; Li, Yeyun; He, Lili; Hou, Ruyan
The uptake, translocation, metabolism, and distribution behavior of glyphosate in nontarget tea plant were investigated. The negative effects appeared to grown tea saplings when the nutrient solution contained glyphosate above 200 mg L(-1). Glyphosate was highest in the roots of the tea plant, where it was also metabolized to aminomethyl phosphonic acid (AMPA). The glyphosate and AMPA in the roots were transported through the xylem or phloem to the stems and leaves. The amount of AMPA in the entire tea plant was less than 6.0% of the amount of glyphosate. The glyphosate level in fresh tea shoots was less than that in mature leaves at each day. These results indicated that free glyphosate in the soil can be continuously absorbed by, metabolized in, and transported from the roots of the tea tree into edible leaves, and therefore, free glyphosate residues in the soil should be controlled to produce teas free of glyphosate.
Zink, Alexander; Traidl-Hoffmann, Claudia
Green tea consumption has a long tradition in Asian countries--especially China. The epidemiologically and experimentally observed anticarcinogenic and antiinflammatory effects of green tea have led to the implementation of green tea extracts in multiple therapeutic applications - both in dermatological and cosmeceutical preparations. The most abundant evidence exists for the anticarcinogenic and chemopreventive effect of green tea or its major constituent epigallocatechin-3-gallate. Almost equally evident is the effect in infectious diseases such as cutaneous viral infections. For external genital warts, a topical ointment with green tea extracts was licensed in the USA in 2010, and recently also in Europe. Experimental evidence pinpointing the block of central signal transduction factors in inflammatory mechanisms has led to the evaluation of catechins in inflammatory disorders such as atopic dermatitis. The belief of green tea as a "wonder weapon" against diseases dates back thousands of years. According to a Chinese legend, ancient Emperor Shen Nung noted a delightful aroma after some leaves of a nearby tree had fallen into boiling water. He immediately proclaimed the new "drink" as "heaven-sent", starting the belief - persisting until today - of green tea as a medication from nature against many different diseases. This review summarizes biological effects and clinical implications of green tea. © 2015 Deutsche Dermatologische Gesellschaft (DDG). Published by John Wiley & Sons Ltd.
Chen, Yulong; Duan, Jun; Yang, Shaoyu; Yang, En; Jiang, Yuming
Oolong tea is one of the most popular beverages due to the presence of significant amount of catechins. Experiments were conducted to investigate the effect of girdling treatment on levels of catechins in fresh tea leaf related to quality of the 'Huang Zhi Xiang' Oolong tea (Camellia sinensis). The variations in the levels of catechins in fresh tea leaf and the quality score (QS) of the 'Huang Zhi Xiang' Oolong tea were examined. The study demonstrated that girdling treatment increased significantly the levels of (-)-epicatechin, (-)-epigallocatechin, (-)-epigallocatechin gallate, (-)-epicatechin gallate, total catechins, simple catechin, and catechin gallate present in fresh leaf of tea trees. Furthermore, the girdling treatment improved significantly the quality of the 'Huang Zhi Xiang' Oolong tea. Thus, it was suggested that application of girdling treatment could be an effective agronomic practice to increase the quality of 'Huang Zhi Xiang' Oolong tea.
Compost teas are often reported to have numerous benefits for landscape professionals and home gardeners. However, many of these benefits are not supported by the scientific literature. This article presents a brief summary of the scientific results and the merits of using composts teas for diseas...
Pazyar, Nader; Feily, Amir; Kazerouni, Afshin
The purpose of this brief review is to summarize all in vitro, in vivo, and controlled clinical trials on green tea preparations and their uses in dermatology. An extensive literature search was carried out to identify in vivo and in vitro studies as well as clinical trials. Twenty studies were assessed and the results suggest that oral administration of green tea can be effective in the scavenging of free radicals, cancer prevention, hair loss, and skin aging plus protection against the adverse effects associated with psoralen-UV-A therapy. Topical application of green tea extract should be potentially effective for atopic dermatitis, acne vulgaris, rosacea, androgenetic alopecia, hirsutism, keloids, genital warts, cutaneous leishmaniasis, and candidiosis. There are promising results with the use of green tea for several dermatologic conditions; however, the efficacy of oral and topical green tea has not always been confirmed.
Ciemniak, Artur; Mocek, Kamila
Tea is the one of most widely consumed beverage in the world. It is generally believed that tea consumption might have health promoting properties. But residues of certain chemical compounds might impose a health threat on tea drinkers. The main contaminants are heavy metals, fluoride, pesticides and even dioxins. Tea lives which possess a high surface area can be contaminated with atmospheric PAHs. The manufacturing processes may also introduce PAHs into tea lives. The aim of his study was to determine the contamination of black, green, red and white teas by PAHs. In this investigation, content of 23 PAH, i.e 16 EPA PAH and 15 EU PAH were determined in 18 brands of tea and its infusions. The analytical procedure was based on ultrasonic extraction for dried tea and liquid-liquid extraction for infusions. All samples were cleaned up by florisil cartridge. The total content of 23 PAH varied between 22.9 microg/kg to 2945.5 microg/kg and 2.7 microg/kg to 63,1 microg/kg microg/kg for BaP. The analysed tea samples showed an increasing presence of PAH in the following order (mean value): black tea < red tea < green tea < white tea. However the highest content of PAH was found in the one brand of black tea bag both in sum of PAH and BaP content. During tea infusion 1.6% of total PAHs contained in tea was released into the beverage. The dominant PAHs in tea infusion were 2, 3 and 4 rings PAH, while the most toxic compounds were found at trace amounts. The concentrations of total 23 PAHs and BaP in tea infusions ranged from 332.5 ng/dm3 to 2245.9 ng/dm3 and 0.35 ng/dm3 to 18.7 ng/dm3 respectively.
Page, Cristy; Hawes, Emily M
The authors report a clinically relevant and possible cause of haemolytic anaemia from ingestion of a Mexican tea from the Neem tree, also known as Azadirachta indica, in a 35-year-old Hispanic man who was found to have glucose-6-phosphate dehydrogenase deficiency. PMID:24136910
Page, Cristy; Hawes, Emily M
The authors report a clinically relevant and possible cause of haemolytic anaemia from ingestion of a Mexican tea from the Neem tree, also known as Azadirachta indica, in a 35-year-old Hispanic man who was found to have glucose-6-phosphate dehydrogenase deficiency.
Deka, Apranta; Vita, Joseph A.
There is increasing evidence for a protective effect of tea consumption against cardiovascular disease. This review summarizes the available epidemiological data providing evidence for and against such an effect. We also review observational and intervention studies that investigated an effect of tea and tea extracts on cardiovascular risk factors, including blood pressure, serum lipids, diabetes mellitus, and obesity. Finally, we review potential mechanisms of benefit, including anti-inflammatory, anti-oxidant, and anti-proliferative effects, as well as favorable effects on endothelial function. Overall, the observational data suggest a benefit, but results are mixed and likely confounded by lifestyle and background dietary factors. The weight of evidence indicates favorable effects on risk factors and a number of plausible mechanisms have been elucidated in experimental and translational human studies. Despite the growing body evidence, it remains uncertain whether tea consumption should be recommended to the general population or to patients as a strategy to reduce cardiovascular risk. PMID:21477653
Palavan-Unsal, Narcin; Arisan, Elif Damla; Terzioglu, Salih
The distribution of dietary polyamines, putrescine, spermidine and spermine, was determined during processing of Camellia sinensis. Black tea manufacture is carried by a series of processes on fresh tea leaves involving withering, rolling, fermentation, drying and sieving. The aim of this research was to determine the effect of tea processing on the polyamine content in relation with antioxidant enzymes, superoxide dismutase, lipid peroxidase and glutathione peroxidase. Before processing, the spermine content was much higher than the putrescine and spermidine content in green tea leaves. Spermine was significantly decreased during processing while the putrescine and spermine contents increased during withered and rolling and decreased in the following stages. The superoxide dismutase activity increased at the withering stage and declined during processing. The transcript level of the polyamine biosynthesis-responsible enzyme ornithine decarboxylase was reduced during each processing step. This study reveals the importance of protection of nutritional compounds that are essential for health during the manufacturing process.
A beverage, as well as the way it is served, can be a window into the soul of a culture. For the author and her husband, Turkish tea helped them understand and enjoy the culture of Turkey. They learned that the broad nuances of culture can be as instructive as a classroom experience. The tea story begins in Chicago in the spring of 2005 when the…
A beverage, as well as the way it is served, can be a window into the soul of a culture. For the author and her husband, Turkish tea helped them understand and enjoy the culture of Turkey. They learned that the broad nuances of culture can be as instructive as a classroom experience. The tea story begins in Chicago in the spring of 2005 when the…
de Souza Silveira Valente, Júlia; de Oliveira da Silva Fonseca, Anelise; Denardi, Laura Bedin; Dal Ben, Vanessa Silveira; de Souza Maia Filho, Fernando; Baptista, Cristiane Telles; Braga, Caroline Quintana; Zambrano, Cristina Gomes; Alves, Sydney Hartz; de Avila Botton, Sônia; Pereira, Daniela Isabel Brayer
Pythium insidiosum is the etiologic agent of pythiosis, a severe and emerging disease that affects mammals. Failure of conventional antifungal therapies is partially justified by the absence of ergosterol in the plasma membrane of this oomycete. Despite research advancement, the treatment of pythiosis has not been not fully established. The present study investigated the in vitro susceptibility profile of Brazilian isolates of P. insidiosum (n = 20) against Melaleuca alternifolia, Mentha piperita and Origanum vulgare essential oils, and their combinations. Susceptibility tests were performed according to CLSI M38-A2 protocol, and combinations were evaluated by the microdilution cherkerboard method. All tested essential oils showed antimicrobial activity against P. insidiosum, and the greatest activity of O. vulgare was highlighted. Synergistic and/or indifferent effect was observed for all combinations evaluated, especially the M. piperita and O. vulgare combination, which showed 65 % synergism. This is the first study to report in vitro combinations of essential oils against P. insidiosum indicating the susceptibility of this oomycete to M. alternifolia, M. piperita and O. vulgare essential oils, as well as their combinations.
Markum, Eric; Baillie, John
Molluscum contagiosum is a common childhood viral skin condition and is increasingly found as a sexually transmitted disease in adults. Current treatment options are invasive, requiring tissue destruction and attendant discomfort. Fifty-three children (mean age 6.3+5.1 years) with the diagnosis of molluscum contagiosum were treated with twice daily topical application of either essential oil of Melaleuca alternifolia (TTO), a combination of TTO and organically bound iodine (TTO-I), or iodine alone. At the end of 30 days, 48 children were available for follow up. A greater than 90% reduction in the number of lesions was observed in 16 of 19 children treated with TTO-I, while 1 of 16 and 3 of 18 children met the same criteria for improvement in the iodine and TTO groups (P<0.01, ANOVA) respectively by intention-to-treat analysis. No child discontinued treatment due to adverse events. The combination of essential oil of M. alternifolia with organically bound iodine offers a safe therapeutic alternative in the treatment of childhood molluscum. Clinical Trial Registry ACTRN12610000984099.
Yanagimoto, Kenichi; Ochi, Hirotomo; Lee, Kwang-Geun; Shibamoto, Takayuki
Antioxidative activities of volatile extracts from six teas (one green tea, one oolong tea, one roasted green tea, and three black teas) were investigated using an aldehyde/carboxylic acid assay and a conjugated diene assay. The samples were tested at levels of 20, 50, 100, and 200 micrograms/mL of dichloromethane. The results obtained from the two assays were consistent. All extracts except roasted green tea exhibited dose-dependent inhibitory activity in the aldehyde/carboxylic acid assay. A volatile extract from green tea exhibited the most potent activity in both assays among the six extracts. It inhibited hexanal oxidation by almost 100% over 40 days at the level of 200 micrograms/mL. The extract from oolong tea inhibited hexanal oxidation by 50% in 15 days. In the case of the extract from roasted green tea, the lowest antioxidative activity was obtained at the level of 200 micrograms/mL, suggesting that the extract from roasted green tea contained some pro-oxidants. The extracts from the three black teas showed slight anti- or proactivities in both assays. The major volatile constituents of green tea and roasted green tea extracts, which exhibited significant antioxidative activities, were analyzed using gas chromatography-mass spectrometry. The major volatile chemicals with possible antioxidative activity identified were alkyl compounds with double bond(s), such as 3,7-dimethyl-1,6-octadien-3-ol (8.04 mg/kg), in the extract from green tea and heterocyclic compounds, such as furfural (7.67 mg/kg), in the extract from roasted green tea. Benzyl alcohol, which was proved to be an antioxidant, was identified both in a green tea extract (4.67 mg/kg) and in a roasted tea extract (1.35 mg/kg).
Kao, Yung-Hsi; Chang, Hsin-Huei; Lee, Meng-Jung; Chen, Chia-Lin
Tea has been found to possess widespread biological functions based on a variety of laboratory data. The effects of tea on obesity and diabetes have received increasing attention. This paper reviews the evidence for the connections among tea catechins, and obesity and diabetes. Tea catechins, especially (-)-epigallocatechin gallate (EGCG), appear to have antiobesity and antidiabetic effects. While few epidemiological and clinical studies show the health benefits of EGCG on obesity and diabetes, the mechanisms of its actions are emerging based on the various laboratory data. These mechanisms may be related to certain pathways, such as through the modulations of energy balance, endocrine systems, food intake, lipid and carbohydrate metabolism, the redox status, and activities of different types of cells (i. e., fat, liver, muscle, and beta-pancreatic cells). Because the EGCG receptor, the so-called 67-kDa laminin receptor (LR), has been discovered with colocalization of other types of LR and cytoskeleton in both cancer cells and normal cells, this may explain that EGCG possesses numerous actions. The mechanistic results of this review may possibly be utilized in the treatment of obesity, diabetes, and other related diseases using tea- and EGCG-based folk medicines.
Osteoporosis is a major health problem in the elderly, particularly women. Epidemiological evidence has shown an association between tea consumption and the prevention of age-related bone loss in elderly women and men. Ingestion of green tea and green tea bioactive compounds may be beneficial in mit...
Yang, Chung S; Wang, Xin
Extracts of green tea and green tea polyphenols have exhibited inhibitory effects against the formation and development of tumors at different organ sites in animals. These include animal models for skin, lung, oral cavity, esophagus, stomach, intestine, colon, liver, pancreas, bladder, mammary gland, and prostate cancers. In addition to suppressing cell proliferation, promoting apoptosis, and modulating signaling transduction, green tea polyphenols, especially (-)-epigallocatechin-3-gallate, also inhibit cell invasion, angiogenesis, and metastasis. This article reviews data on the cancer preventive activities of green tea polyphenols, possible mechanisms involved, and the relationship between green tea consumption and human cancer risk.
Subramanian, R; Kumar, Chandini S; Sharma, Pankaj
The ready-to-drink (RTD) tea beverages are becoming increasingly popular owing to the health benefits associated with tea polyphenols, but instability due to development of haze and formation of tea cream is a common problem encountered in the product. Membrane technology provides a scope to produce natural, additive-free RTD teas while overcoming the major disadvantages associated with the conventional decreaming methods. Approaches employing membranes for the clarification of extracts from black and green tea have been discussed together with their relative advantages and limitations. The article also outlines the concerns to be addressed in the future attempts employing membrane technology.
Yang, T T; Koo, M W
Chinese teas with different degrees of fermentation were examined for their effect on diet-induced hypercholesterolemia in rats. The teas tested were Chinese Green tea, Jasmine, Iron Buddha, Oolong and Pu erh. Hypercholesterolemia was induced by feeding rats with a cholesterol-enriched diet for 1 week. They were then treated with different tea extracts together with a cholesterol-enriched diet for another 8 weeks. Chinese Green tea and Jasmine tea, both with a minimum degree of fermentation, were found to have significant serum and liver cholesterol lowering effects. They also reduced the increase in liver weight due to lipid deposition. All tea treatments lowered the atherogenic index and increased the HDL-total cholesterol ratio, while HDL-cholesterol and triglyceride levels were not significantly affected. Analysis of catechin levels in tea extracts showed that the individual catechin component in Chinese Green tea and Jasmine tea were significantly higher than the others. (-)-Epicatechin gallate and (-)-epigallocatechin gallate in the tea extracts may account for their hypocholesterolemic effect.
Katiyar, S; Mukhtar, H
This review summarizes available information on epidemiological and experimental data showing an association of tea consumption with cancer prevention. Studies showing cancer risk associated with tea consumption are also summarized. Tea is grown in about 30 countries and, next to water, is the most widely consumed beverage in the world. Experimental studies demonstrating the chemopreventive effects of tea have been conducted principally with green tea; limited studies have also assessed the usefulness of black tea. Majority of these studies have been carried out in skin tumor model system where consumption through drinking water of water extracts of tea or a polyphenolic fraction isolated from tea has been shown to afford protection against chemical carcinogen- or ultraviolet radiation-induced skin tumorigenesis. Tea consumption has also been shown to afford protection against chemical carcinogen-induced lung, forestomach, esophagus, duodenum, pancreas, liver, breast and colon carcinogenesis in specific bioassay models. Evidence has also accumulated showing that tea polyphenols prevent tumor promoter- and ultraviolet B-induced inflammatory responses in murine skin. The species and strains of animals, dose, route, frequency and duration of carcinogen administration, as well as types, route of administration and duration of tea or its polyphenolic component(s) treatment are described in detail. A brief description regarding mechanism(s) responsible for the broad chemopreventive effects of tea is provided. Epidemiologic studies, though inconclusive, in general suggest a possible preventive effect of tea consumption on human cancer. On the basis of available information, epidemiologic and experimental studies are ongoing to draw the possible relationship between tea consumption and cancer causation and prevention. Appropriate strategies for future clinical chemoprevention trials to translate animal data to human cancer risk are warranted.
Lee, Shih-Chieh; Wang, Chia-Hsiang; Yen, Cheng-En; Chang, Chieh
The major aim of made tea identification is to identify the variety and provenance of the tea plant. The present experiment used 113 tea plants [Camellia sinensis (L.) O. Kuntze] housed at the Tea Research and Extension Substation, from which 113 internal transcribed spacer 2 (ITS2) fragments, 104 trnL intron, and 98 trnL-trnF intergenic sequence region DNA sequences were successfully sequenced. The similarity of the ITS2 nucleotide sequences between tea plants housed at the Tea Research and Extension Substation was 0.379-0.994. In this polymerase chain reaction-amplified noncoding region, no varieties possessed identical sequences. Compared with the trnL intron and trnL-trnF intergenic sequence fragments of chloroplast cpDNA, the proportion of ITS2 nucleotide sequence variation was large and is more suitable for establishing a DNA barcode database to identify tea plant varieties. After establishing the database, 30 imported teas and 35 domestic made teas were used in this model system to explore the feasibility of using ITS2 sequences to identify the varieties and provenances of made teas. A phylogenetic tree was constructed using ITS2 sequences with the unweighted pair group method with arithmetic mean, which indicated that the same variety of tea plant is likely to be successfully categorized into one cluster, but contamination from other tea plants was also detected. This result provides molecular evidence that the similarity between important tea varieties in Taiwan remains high. We suggest a direct, wide collection of made tea and original samples of tea plants to establish an ITS2 sequence molecular barcode identification database to identify the varieties and provenances of tea plants. The DNA barcode comparison method can satisfy the need for a rapid, low-cost, frontline differentiation of the large amount of made teas from Taiwan and abroad, and can provide molecular evidence of their varieties and provenances. Copyright © 2016. Published by Elsevier B.V.
Haines, J D
A patient whose main symptom is sweating can present a diagnostic challenge. Dr Haines describes a case in which diaphoresis was caused not by a conventional medication or illness but rather by a life-style change in which the patient began consuming sassafras tea.
Yang, Chung S; Maliakal, Pius; Meng, Xiaofeng
Tea has received a great deal of attention because tea polyphenols are strong antioxidants, and tea preparations have inhibitory activity against tumorigenesis. The bioavailability and biotransformation of tea polyphenols, however, are key factors limiting these activities in vivo. The inhibition of tumorigenesis by green or black tea preparations has been demonstrated in animal models on different organ sites such as skin, lung, oral cavity, esophagus, forestomach, stomach, small intestine, colon, pancreas, and mammary gland. Epidemiological studies, however, have not yielded clear conclusions concerning the protective effects of tea consumption against cancer formation in humans. The discrepancy between the results from humans and animal models could be due to 1) the much higher doses of tea used in animals in comparison to human consumption, 2) the differences in causative factors between the cancers in humans and animals, and 3) confounding factors limiting the power of epidemiological studies to detect an effect. It is possible that tea may be only effective against specific types of cancer caused by certain etiological factors. Many mechanisms have been proposed for the inhibition of carcinogenesis by tea, including the modulation of signal transduction pathways that leads to the inhibition of cell proliferation and transformation, induction of apoptosis of preneoplastic and neoplastic cells, as well as inhibition of tumor invasion and angiogenesis. These mechanisms need to be evaluated and verified in animal models or humans in order to gain more understanding on the effect of tea consumption on human cancer.
Abd El-Aty, A M; Choi, Jeong-Heui; Rahman, Md Musfiqur; Kim, Sung-Woo; Tosun, Alev; Shim, Jae-Han
Consumers are very aware of contaminants that could pose potential health hazards. Most people drink tea as an infusion (adding hot water); however, in some countries, including India, China and Egypt, tea is drunk as a decoction (tea and water are boiled together). An infusion usually brings the soluble ingredients into solution, whereas a decoction brings all soluble and non-soluble constituents together. Therefore, a cup of tea may contain various kinds of contaminants. This review focuses on green and black tea because they are most commonly consumed. The target was to examine the transfer rate of contaminants - pesticides, environmental pollutants, mycotoxins, microorganisms, toxic heavy metals, radioactive isotopes (radionuclides) and plant growth regulators - from tea to infusion/brewing, factors contributing to the transfer potential and contaminants degradation, and residues in or on the spent leaves. It is concluded that most contaminants leaching into tea infusion are not detected or are detected at a level lower than the regulatory limits. However, the traditional practice of over-boiling tea leaves should be discouraged as there may be a chance for more transfer of contaminants from the tea to the brew.
Kanwar, Jyoti; Taskeen, Mujtaba; Mohammad, Imthiyaz; Huo, Congde; Chan, Tak Hang; Dou, Qing Ping
Over the past decade many scientific and medical studies have focused on green tea for its long-purported health benefits. There is convincing evidence that tea is a cup of life. It has multiple preventive and therapeutic effects. This review thus focuses on the recent advances of tea polyphenols and their applications in the prevention and treatment of human cancers. Of the various polyphenols in tea, (−)-Epigallocatechin-3-gallate (EGCG) is the most abundant, and active compound studied in tea research. EGCG inhibits several molecular targets to inhibit cancer initiation and modulates several essential survival pathways to block cancer progression. Herein, we describe the various mechanisms of action of EGCG and also discuss previous and current ongoing clinical trials of EGCG and green tea polyphenols in different cancer types. PMID:22201858
Satoh, Eiki; Tohyama, Naoki; Nishimura, Masakazu
Although the antioxidant properties of green, oolong, and black teas have been well studied, antioxidant activity has not been examined in roasted tea. Therefore, in the current studies, we investigated the antioxidant activity of roasted tea in comparison with those of green, oolong, and black teas. Using water extracts of the various teas, we examined the total phenolic content as well as the antioxidant activities, including the reducing power, the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity, and the inhibition of hemolysis caused by 2,2'-azo-bis(2-amidinopropane) dihydrochloride (AAPH)-induced lipid oxidation in erythrocyte membranes. The roasted tea contained lower levels of total phenolics than green, oolong, or black tea (green tea > oolong tea > black tea > roasted tea). The relative reducing power and DPPH scavenging activity decreased in the following order: green tea > roasted tea > oolong tea > black tea. Also, green tea was more effective against AAPH-induced erythrocyte hemolysis than other teas (green tea>roasted tea = oolong tea = black tea). These results suggest that roasted tea is beneficial to health, in humans, because of its high antioxidant activity.
Green tea polyphenols have emerged over the past two decades as an important dietary factor for health promotion. There is considerable evidence that tea polyphenols, in particular (−)-epigallocatechin-3-gallate (EGCG) inhibit carcinogenesis. However, the mechanisms for the cancer-preventive activity of EGCG are not completely characterized and many features remain to be elucidated. Recently we have identified a cell-surface EGCG receptor and the relating molecules that confer EGCG responsiveness to many cancer cells at physiological concentrations. Here, we review some of the reported mechanisms for the cancer chemopreventive action of EGCG and provide an overview of several molecules that sense and manage the physiological functions of EGCG. PMID:21422740
Kim, Youngmok; Talcott, Stephen T
Tea creaming is the development of a cloudy or hazy appearance in tea and ready-to-drink tea products on cooling and is highly undesirable in the tea beverage industry. Commonly associated with fermented black or oolong teas, the objective of this study was to investigate the physicochemical mechanism of the formation of tea cream in nonfermented green tea (Camellia sinensis) and a caffeine-containing botanical tea from yaupon holly (Ilex vomitoria) that is free of catechin-based polyphenolics. Four tea-creaming activators (phenolics, soluble protein, caffeine, and metal ions) were added to tea infusions as well as decaffeinated teas created by chloroform extraction. Tea-creaming activators increased the weight and turbidity of both teas with the exception of soluble protein addition (as bovine serum albumin) to green tea, whereas the greatest increase in turbidity occurred with the addition of metal ions in green tea. Tea creaming was equally developed at three incubation temperatures (4, 25, and 40 °C) in both teas, but tea-creaming compositions in each tea were different at the incubating temperatures. The antioxidant capacity of each tea was lowered after creaming due to the loss of antioxidants that participated in tea cream formation.
Chen, Zong-mao; Lin, Zhi
Originating in China, tea and tea planting have spread throughout the world since the middle of the Tang dynasty. Now people from 160 countries in the world are accustomed to tea drinking. A brief history of tea's medicinal role in China and its spread to the world are introduced. The effectiveness of tea active components and tea drinking on major human diseases, including cancer, metabolic syndrome, cardiovascular disease, and neurodegenerative diseases, is discussed. Also presented are some related issues, such as the bioavailability of tea active components, the new formulations of tea polyphenols, and the safety for consumers of dietary supplements containing tea polyphenols.
Osteoporosis is a major health problem in elderly men and women. Epidemiological evidence has shown association between tea consumption and age-related bone loss in elderly men and women. The aim of this review is to provide a systemic review of green tea and bone health to cover the following topi...
Chen, Di; Daniel, Kenyon G; Kuhn, Deborah J; Kazi, Aslamuzzaman; Bhuiyan, Mohammad; Li, Lianhai; Wang, Zhigang; Wan, Sheng Biao; Lam, Wai Har; Chan, Tak Hang; Dou, Q Ping
The cancer-preventive effects of green tea and its main constituent (-)-epigallocatechin gallate [(-)-EGCG] are widely supported by results from epidemiological, cell culture, animal and clinical studies in the recent decade. In vitro cell culture studies show that tea polyphenols potently induce apoptotic cell death and cell cycle arrest in tumor cells but not in their normal cell counterparts. Green tea polyphenols affect several signal transduction pathways, including growth factor-mediated, the mitogen-activated protein kinase (MAPK)-dependent, and ubiquitin/proteasome degradation pathways. Epidemiological studies have suggested that the consumption of green tea lowers the risk of cancer. Various animal studies have revealed that treatment by green tea inhibits tumor incidence and multiplicity in different organ sites such as skin, lung, liver, stomach, mammary gland and colon. Phase I and II clinical trials were carried out recently to explore the anticancer effects of green tea in patients with cancer. At this time, more mechanistic research, animal studies, and clinical trials are necessary to further evaluate the role of green tea in cancer prevention.
Historically, the medicinal use of green tea dates back to China 4700 years ago and drinking tea continues to be regarded traditionally in Asia as a general healthful practice. Numerous scientific publications now attest to the health benefits of both black and green teas, including clinical and epidemiological studies. Although all tea contains beneficial antioxidants, high-quality green and white teas have them in greater concentrations than black tea. Today, scientists believe that the main active ingredients of green tea include the polyphenols, in particular the catechins and the amino acid, theanine. Studies on the health benefits of drinking tea, particularly green tea, are finding exciting results, particularly in cancer research. Modern studies in both Asia and the West have provided encouraging results indicating that drinking green tea contributes to fighting many different kinds of cancers including stomach, oesophageal, ovarian and colon. Recent studies describing the health benefits of these compounds will be reviewed.
Many studies, both national and international, have shown that tea has protective effects on many chronic diseases and their risk factors. In cancer prevention, our studies indicated that tea drinking could inhibit the carcinogenicity of various chemical carcinogens, including oral tumors induced by 7,12-dimethylbenz[a]anthracene (DMBA) in Golden hamsters, esophageal tumors in rats by blocking in vivo synthesis of N-Nitroso-methylbenzylamine (NMBzA), esophageal cancer induced by NMBzA in rats, precancerous liver lesions (r-GT and GST-P) induced by diethylnitrosamine (DENA) in rats, intestinal preneoplastic lesion (ACF) and intestinal tumors induced by 1,2-dimethyl-hydrazine (DMH) in rats, lung carcinoma induced by nitrosamine 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone(NNK) in A/J mice. Our studies have also shown that the protective effects of tea against cancer is a combined effects of various tea ingredients, among which the major ones are polyphenols and tea pigments. Based on animal studies, antioxidant properties, protection against DNA damage and modulation of immune functions were found to be the main mechanisms of anticancer effects of tea. In human trials, tea drinking showed protective effects against oxidative damage and DNA damage caused by cigarette smoking. Mixed tea drinking significantly blocked lesion progress in patients with oral mucosa leukoplakia, therefore, demonstrated its protective effects on oral cancer. Our studies have also shown effects of tea on prevention of cardiovascular diseases (CVD). For example, tea pigments was found to significantly inhibit LDL oxidation induced by Cu2+, Fe2+ in in vitro studies. In vivo studies showed that tea could prevent blood coagulation, facilitate fibrinogen dissolution, inhibit platelet aggregation, lower endothelin levels, enhance GSH-Px activities, protect against oxidated LDL-induced damage in endothelium cells, and prevent atherosclerosis of coronary arteries. The mechanisms of these protective
FORESTER, SARAH C.; LAMBERT, JOSHUA D.
Consumption of green tea (Camellia sinensis) may provide protection against chronic diseases, including cancer. Green tea polyphenols are believed to be responsible for this cancer preventive effect, and the antioxidant activity of the green tea polyphenols has been implicated as a potential mechanism. This hypothesis has been difficult to study in vivo due to metabolism of these compounds and poor understanding of the redox environment in vivo. Green tea polyphenols can be direct antioxidants by scavenging reactive oxygen species or chelating transition metals as has been demonstrated in vitro. Alternatively, they may act indirectly by up-regulating phase II antioxidant enzymes. Evidence of this latter effect has been observed in vivo, yet more work is required to determine under which conditions these mechanisms occur. Green tea polyphenols can also be potent pro-oxidants, both in vitro and in vivo, leading to the formation of hydrogen peroxide, the hydroxyl radical, and superoxide anion. The potential role of these pro-oxidant effects in the cancer preventive activity of green tea is not well understood. The evidence for not only the antioxidant, but also pro-oxidant, properties of green tea are discussed in the present review. PMID:21538850
Chen, Zong-mao; Lin, Zhi
Originating in China, tea and tea planting have spread throughout the world since the middle of the Tang dynasty. Now people from 160 countries in the world are accustomed to tea drinking. A brief history of tea’s medicinal role in China and its spread to the world are introduced. The effectiveness of tea active components and tea drinking on major human diseases, including cancer, metabolic syndrome, cardiovascular disease, and neurodegenerative diseases, is discussed. Also presented are some related issues, such as the bioavailability of tea active components, the new formulations of tea polyphenols, and the safety for consumers of dietary supplements containing tea polyphenols. PMID:25644464
Wu, Anna H; Butler, Lesley M
The identification of modifiable lifestyle factors that could reduce the risk of breast cancer is a research priority. Despite the enormous chemo preventive potential of green tea and compelling evidence from animal studies, its role in breast cancer development in humans is still unclear. Part of the uncertainty is related to the relatively small number of epidemiological studies on green tea and breast cancer and that the overall results from case-control studies and prospective cohort studies are discordant. In addition, the mechanisms by which green tea intake may influence risk of breast cancer in humans remains not well studied. We review the human studies that have evaluated the relationship between green tea intake and four biomarkers (sex steroid hormones, mammographic density, insulin-like growth factor, adiponectin) that are believed to be important in breast cancer development. Results from these biomarker studies are also inconclusive. Limitations of human studies and areas of further investigations are discussed. PMID:21538855
Zhu, Qin Yan; Hackman, Robert M; Ensunsa, Jodi L; Holt, Roberta R; Keen, Carl L
While the antioxidative properties of green and black tea have been extensively studied, less attention has been given to these properties in oolong tea. The reducing powers, the 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging activities, the amount of total phenolic compounds, the inhibitory effect on FeCl(2)/H(2)O(2) (Fenton reaction system)-induced DNA damage, and the inhibitory effect on erythrocyte hemolysis of an oolong tea water extract (OTE) were evaluated in the present study. The OTE was found to have strong antioxidative activities in all of the model systems tested. When the OTE was separated into different fractions according to molecular weight, it was found that the fractions with higher amounts of phenolic compounds (lower molecular weight) have stronger antioxidative activities. The present results support the concept that oolong tea contains several low molecular weight antioxidants that may have health promotion activities.
Lin, Xiaorong; Chen, Zhongzheng; Zhang, Yuanyuan; Luo, Wei; Tang, Hao; Deng, Baibiao; Deng, Jian; Li, Bin
Tea cream is prevalent in various types of tea, yet a comparison of the mechanism of creaming in different teas remains uncertain. Here, we compared physicochemical characteristics, phytochemical composition, and simulated digestive profiles of green tea and black tea cream, looking to exploit their concentration and structure based mechanisms and in vitro bioaccessibility. Green tea cream particles were roughly one order of magnitude larger than those of black tea in size. Moreover, creaming concentrations of catechins, proteins and methylxanthines of green tea were dramatically higher than black tea. As major creaming components, gallated catechins, theaflavins, thearubigins, theabrownines, proteins and methylxanthines also exhibited high creaming affinities. Green tea cream particles, which were completely destroyed by simulated digestion, had few impacts on digestive recoveries of catechins and methylxanthines. In comparison, black tea cream particles were more stable under mimicking digestion, and clarification remarkably decreased the in vitro bioaccessibility of catechins and methylxanthines. Copyright © 2014 Elsevier Ltd. All rights reserved.
Khan, Naghma; Mukhtar, Hasan
Tea, next to water is the cheapest beverage humans consume. Drinking the beverage tea has been considered a healthpromoting habit since ancient times. The modern medicinal research is providing a scientific basis for this belief. The evidence supporting the health benefits of tea drinking grows stronger with each new study that is published in the scientific literature. Tea plant Camellia sinensis has been cultivated for thousands of years and its leaves have been used for medicinal purposes. Tea is used as a popular beverage worldwide and its ingredients are now finding medicinal benefits. Encouraging data showing cancer-preventive effects of green tea from cell-culture, animal and human studies have emerged. Evidence is accumulating that black tea may have similar beneficial effects. Tea consumption has also been shown to be useful for prevention of many debilitating human diseases that include maintenance of cardiovascular and metabolic health. Various studies suggest that polyphenolic compounds present in green and black tea are associated with beneficial effects in prevention of cardiovascular diseases, particularly of atherosclerosis and coronary heart disease. In addition, anti-aging, antidiabetic and many other health beneficial effects associated with tea consumption are described. Evidence is accumulating that catechins and theaflavins, which are the main polyphenolic compounds of green and black tea, respectively, are responsible for most of the physiological effects of tea. This article describes the evidences from clinical and epidemiological studies in the prevention of chronic diseases like cancer and cardiovascular diseases and general health promotion associated with tea consumption.
Ye, Jian-Hui; Liang, Yue-Rong; Jin, Jing; Liang, Hue-Ling; Du, Ying-Ying; Lu, Jian-Liang; Ye, Qian; Lin, Chen
The caffeine level of instant tea extracted from decaffeinated leaf tea with 4.0 mg g-1 caffeine is commonly above 10.0 mg g-1, the maximum limit of caffeine for decaffeinated instant tea. Further removal of caffeine by active carbon (AC) from the green tea extract was investigated. It showed that the removal of caffeine from the tea extract solutions depended on the treatment time and tea extract concentration while the ethanol concentration and pH had little effect on the removal of caffeine. According to the removal of caffeine and the ratio of total catechins to caffeine in the tested samples, the optimum decaffeination conditions were determined to be as follows: tea extract concentration 15-30 g L-1 for common tea extract but higher for partially decaffeinated tea leaf extract; ratio of tea solution to AC, 100 mL:4 g; treatment time, 4 h; and natural tea extract pH. Instant tea powder extracted from partially decaffeinated leaf tea with a caffeine level of 4.03 mg g-1 and further decaffeinated by AC had a caffeine level of 7.81 mg g-1, which was 31% lower than that without AC treatment.
Graham, H N
Tea is grown in about 30 countries but is consumed worldwide, although at greatly varying levels. It is the most widely consumed beverage aside from water with a per capita worldwide consumption of approximately 0.12 liter per year. Tea is manufactured in three basic forms. Green tea is prepared in such a way as to preclude the oxidation of green leaf polyphenols. During black tea production oxidation is promoted so that most of these substances are oxidized. Oolong tea is a partially oxidized product. Of the approximately 2.5 million metric tons of dried tea manufactured, only 20% is green tea and less than 2% is oolong tea. Green tea is consumed primarily in China, Japan, and a few countries in North Africa and the Middle East. Fresh tea leaf is unusually rich in the flavanol group of polyphenols known as catechins which may constitute up to 30% of the dry leaf weight. Other polyphenols include flavanols and their glycosides, and depsides such as chlorogenic acid, coumarylquinic acid, and one unique to tea, theogallin (3-galloylquinic acid). Caffeine is present at an average level of 3% along with very small amounts of the other common methylxanthines, theobromine and theophylline. The amino acid theanine (5-N-ethylglutamine) is also unique to tea. Tea accumulates aluminum and manganese. In addition to the normal complement of plant cell enzymes, tea leaf contains an active polyphenol oxidase which catalyzes the aerobic oxidation of the catechins when the leaf cell structure is disrupted during black tea manufacture. The various quinones produced by the enzymatic oxidations undergo condensation reactions which result in a series of compounds, including bisflavanols, theaflavins, epitheaflavic acids, and thearubigens, which impart the characteristic taste and color properties of black tea. Most of these compounds readily form complexes with caffeine. There is no tannic acid in tea. Thearubigens constitute the largest mass of the extractable matter in black tea but
Fazakerley, Andrew; Moore, Tom; Owen, Chris; Pollock, Craig; Wicks, Rob; Samara, Marilia; Rae, Jonny; Hancock, Barry; Kataria, Dhiren; Rust, Duncan
Turbulence Heating ObserveR (THOR) is the first mission ever flown in space dedicated to plasma turbulence. The Turbulence Electron Analyser (TEA) will measure the plasma electron populations in the mission's Regions of Interest. It will collect a 3D electron velocity distribution with cadences as short as 5 ms. The instrument will be capable of measuring energies up to 30 keV. TEA consists of multiple electrostatic analyser heads arranged so as to measure electrons arriving from look directions covering the full sky, i.e. 4 pi solid angle. The baseline concept is similar to the successful FPI-DES instrument currently operating on the MMS mission. TEA is intended to have a similar angular resolution, but a larger geometric factor. In comparison to earlier missions, TEA improves on the measurement cadence. For example, MMS FPI-DES routinely operates at 30 ms cadence. The objective of measuring distributions at rates as fast as 5 ms is driven by the mission's scientific requirements to resolve electron gyroscale size structures, where plasma heating and fluctuation dissipation is predicted to occur. TEA will therefore be capable of making measurements of the evolution of distribution functions across thin (a few km) current sheets travelling past the spacecraft at up to 600 km/s, of the Power Spectral Density of fluctuations of electron moments and of distributions fast enough to match frequencies with waves expected to be dissipating turbulence (e.g. with 100 Hz whistler waves).
Yokel, Robert A.; Florence, Rebecca L.
The objective was to estimate oral Al bioavailability from tea infusion in the rat, using the tracer 26Al. 26Al citrate was injected into tea leaves. An infusion was prepared from the dried leaves and given intra-gastrically to rats which received concurrent intravenous 27Al infusion. Oral Al bioavailability (F) was calculated from the area under the 26Al, compared to 27Al, serum concentration × time curves. Bioavailability from tea averaged 0.37%; not significantly different from water (F = 0.3%), or basic sodium aluminum phosphate (SALP) in cheese (F = 0.1 to 0.3%), but greater than acidic SALP in a biscuit (F = 0.1%). Time to maximum serum 26Al concentration was 1.25, 1.5, 8 and 4.8 h, respectively. These results of oral Al bioavailability × daily consumption by the human suggest tea can provide a significant amount of the Al that reaches systemic circulation. This can allow distribution to its target organs of toxicity, the central nervous, skeletal and hematopoietic systems. Further testing of the hypothesis that Al contributes to Alzheimer's disease may be more warranted with studies focusing on total average daily food intake, including tea and other foods containing appreciable Al, than drinking water. PMID:18848597
Rosen, S; Elvin-Lewis, M; Beck, F M; Beck, E X
Teas varying in fluoride and tannin concentration were evaluated in rats for anticariogenic activity. There was a direct correlation between fluoride in tea and the inhibition of sulcal caries in rats, whereas no relationship was observed between tannin and this type of lesion. Teas also had a significant effect on caries progression and imparted a black stain to the teeth.
Background Tea is one of the most popular beverages in the world. Many species in the Thea section of the Camellia genus can be processed for drinking and have been domesticated. However, few investigations have focused on the genetic consequence of domestication and geographic origin of landraces on tea plants using credible wild and planted populations of a single species. Here, C. taliensis provides us with a unique opportunity to explore these issues. Results Fourteen nuclear microsatellite loci were employed to determine the genetic diversity and domestication origin of C. taliensis, which were represented by 587 individuals from 25 wild, planted and recently domesticated populations. C. taliensis showed a moderate high level of overall genetic diversity. The greater reduction of genetic diversity and stronger genetic drift were detected in the wild group than in the recently domesticated group, indicating the loss of genetic diversity of wild populations due to overexploitation and habitat fragmentation. Instead of the endangered wild trees, recently domesticated individuals were used to compare with the planted trees for detecting the genetic consequence of domestication. A little and non-significant reduction in genetic diversity was found during domestication. The long life cycle, selection for leaf traits and gene flow between populations will delay the emergence of bottleneck in planted trees. Both phylogenetic and assignment analyses suggested that planted trees may have been domesticated from the adjacent central forest of western Yunnan and dispersed artificially to distant places. Conclusions This study contributes to the knowledge about levels and distribution of genetic diversity of C. taliensis and provides new insights into genetic consequence of domestication and geographic origin of planted trees of this species. As an endemic tea source plant, wild, planted and recently domesticated C. taliensis trees should all be protected for their unique
Shen, Fwu-Ming; Chen, Hong-Wen
Tea infusion is the most frequently consumed beverage worldwide next to water, with about 20 billion cups consumed daily. In Taiwan, daily consumption averages 2.5 cups of tea infusion per person. Many studies have concluded that tea has numerous beneficial effects on health. However, some undesirable trace elements, such as arsenic, chromium, cadmium, lead, etc., are a concern. This study has three aims: (1) to measure the concentrations of arsenic and heavy metal elements, such as chromium, cadmium, and lead, as well as the essential trace elements contained in dried tea leaves of the common brands in Taiwan; (2) to determine the percentage released and concentration of each of these elements after infusion of these tea leaves with boiling water; (3) to assess the carcinogenic risk from daily tea consumption, to provide reference values for the general public. This study showed the total content of arsenic and heavy metals in green tea, oolong tea, and black tea produced in Taiwan was 0.11, 5.61, and 10.11 microg/g, respectively, indicating that the level of arsenic and heavy metal contamination of tea leaves was lower in Taiwan than other regions of the world. The hazard index (HI) of daily tea drinking of green tea, oolong tea, and black tea was low and within the bounds of safety (<1). Tea is an indispensable part of everyday life for many people in Taiwan, studies should continue to ensure that public health is maintained.
Liu, X-P; Gong, C-M; Fan, Y-Y; Eiblmeier, M; Zhao, Z; Han, G; Rennenberg, H
This study aimed to identify drought-mediated differences in amino nitrogen (N) composition and content of xylem and phloem in trees having different symbiotic N(2)-fixing bacteria. Under controlled water availability, 1-year-old seedlings of Robinia pseudoacacia (nodules with Rhizobium), Hippophae rhamnoides (symbiosis with Frankia) and Buddleja alternifolia (no such root symbiosis) were exposed to control, medium drought and severe drought, corresponding soil water content of 70-75%, 45-50% and 30-35% of field capacity, respectively. Composition and content of amino compounds in xylem sap and phloem exudates were analysed as a measure of N nutrition. Drought strongly reduced biomass accumulation in all species, but amino N content in xylem and phloem remained unaffected only in R. pseudoacacia. In H. rhamnoides and B. alternifolia, amino N in phloem remained constant, but increased in xylem of both species in response to drought. There were differences in composition of amino compounds in xylem and phloem of the three species in response to drought. Proline concentrations in long-distance transport pathways of all three species were very low, below the limit of detection in phloem of H. rhamnoides and in phloem and xylem of B. alternifolia. Apparently, drought-mediated changes in N composition were much more connected with species-specific changes in C:N ratios. Irrespective of soil water content, the two species with root symbioses did not show similar features for the different types of symbiosis, neither in N composition nor in N content. There was no immediate correlation between symbiotic N fixation and drought-mediated changes in amino N in the transport pathways. © 2012 German Botanical Society and The Royal Botanical Society of the Netherlands.
Plant extracts have been widely used as topical applications for wound-healing, anti-aging, and disease treatments. Examples of these include ginkgo biloba, echinacea, ginseng, grape seed, green tea, lemon, lavender, rosemary, thuja, sarsaparilla, soy, prickly pear, sagebrush, jojoba, aloe vera, allantoin, feverwort, bloodroot, apache plume, and papaya. These plants share a common character: they all produce flavonoid compounds with phenolic structures. These phytochemicals are highly reactive with other compounds, such as reactive oxygen species and biologic macromolecules, to neutralize free radicals or initiate biological effects. A short list of phenolic phytochemicals with promising properties to benefit human health includes a group of polyphenol compounds, called catechins, found in green tea. This article summarizes the findings of studies using green tea polyphenols as chemopreventive, natural healing, and anti-aging agents for human skin, and discusses possible mechanisms of action.
Soshitsu Sen's keynote speech before a symposium on population and the environment is summarized unofficially by the editorial staff. The instability of human thinking is given as the cause for the present destruction of the environment. In a visit to the His Majesty King of Sweden, Sen remarked that stabilizing human minds can be achieved within the tea ceremony through "serving tea heartily, receiving it with gratitude, and offering it to another." In this way, the spirit of concern for others can be practiced in everyday life and tranquility of mind reached. News broadcasts of starving parents and children as victims of civil war are disheartening. The Japanese people are not suffering such hunger, even though the economy has not been as robust as desired. The analogy is provided in the story by Chuang Chou about King Hun Dun and King Xiu and man's good intentions, which nonetheless destroy the earth. Japan has experienced forest and environmental destruction on the road to economic prosperity and satisfaction of self-interests. The advice on living in accord with nature is to appreciate each season for its own changes. For example, when it is the winter season, the complaint is about the cold and the desire is for spring; but when spring comes, the desire is for the cooler weather of fall. the ordinary way is to appreciate all seasons and is the best way of sustaining a healthy environment. In the garden of the tea hut, humans enter without their worldly title, position, and means; at the water basin, hands and mouth are cleansed, and entrance is made through a small hole into the hut much the same as emerging from the womb. Worldly matters are dispensed with and purity of thought is shared in the sharing of the bowl of green tea, saying "after you" to one another. Christianity and the Way of Tea share the same symbols of purification. The black tea bowl is in harmony with the green tea. Fatigue is relieved when gazing upon the color green; examples are given
SUZUKI, Yasuo; MIYOSHI, Noriyuki; ISEMURA, Mamoru
Green tea is manufactured from the leaves of the plant Camellia sinensis Theaceae and has been regarded to possess anti-cancer, anti-obesity, anti-atherosclerotic, anti-diabetic, anti-bacterial, and anti-viral effects. Many of the beneficial effects of green tea are related to the activities of (−)-epigallocatechin gallate (EGCG), a major component of green tea catechins. For about 20 years, we have engaged in studies to reveal the biological activities and action mechanisms of green tea and EGCG. This review summarizes several lines of evidence to indicate the health-promoting properties of green tea mainly based on our own experimental findings. PMID:22450537
Srinivasan, Radhika; Smolinske, Susan; Greenbaum, David
Kombucha tea is a health beverage made by incubating the Kombucha “mushroom” in tea and sugar. Although therapeutic benefits have been attributed to the drink, neither its beneficial effects nor adverse side effects have been reported widely in the scientific literature. Side effects probably related to consumption of Kombucha tea are reported in four patients. Two presented with symptoms of allergic reaction, the third with jaundice, and the fourth with nausea, vomiting, and head and neck pain. In all four, use of Kombucha tea in proximity to onset of symptoms and symptom resolution on cessation of tea drinking suggest a probable etiologic association. PMID:9346462
Cheng, Tsung O
Tea is one of the most widely consumed beverages in the world, next only to water. It can be categorized into three types, depending on the level of fermentation, i.e., green (unfermented), oolong (partially fermented) and black (fermented) tea. In general, green tea has been found to be superior to black tea in terms of antioxidant activity owing to the higher content of (-)-epigallocatechin gallate. The processes used in the manufacture of black tea are known to decrease levels of the monometric catechins to a much greater extent than the less severe conditions applied to other teas. The cardioprotective effect of flavonoids from green tea can be attributed to not only antioxidant, antithrombogenic and anti-inflammatory properties but also improvement of coronary flow velocity reserve. In this article, I will discuss the effects of green tea on atherosclerosis, coronary heart disease, hypertension, diabetes, metabolic syndrome and obesity, and, finally, its comparison with black tea.
Saric, Suzana; Notay, Manisha; Sivamani, Raja K.
Polyphenols are antioxidant molecules found in many foods including nuts, fruits, vegetables, chocolate, wine, and tea. Polyphenols have antimicrobial, anti-inflammatory, and antineoplastic properties. Recent studies suggest that tea polyphenols may be used for reducing sebum production in the skin and for treatment of acne vulgaris. This review examines the evidence for use of topically and orally ingested tea polyphenols against sebum production and for acne treatment and prevention. The PubMed database was searched for studies on tea polyphenols, sebum secretion, and acne vulgaris. Of the 59 studies found, eight met the inclusion criteria. Two studies evaluated tea polyphenol effects on sebum production; six studies examined tea polyphenol effects on acne vulgaris. Seven studies evaluated topical tea polyphenols; one study examined systemic tea polyphenols. None of the studies evaluated both topical and systemic tea polyphenols. Tea polyphenol sources included green tea (six studies) and tea, type not specified (two studies). Overall, there is some evidence that tea polyphenols in topical formulation may be beneficial in reducing sebum secretion and in treatment of acne. Research studies of high quality and with large sample sizes are needed to assess the efficacy of tea polyphenols in topical and oral prevention of acne vulgaris and lipid synthesis by the sebaceous glands. PMID:28036057
Saric, Suzana; Notay, Manisha; Sivamani, Raja K
Polyphenols are antioxidant molecules found in many foods including nuts, fruits, vegetables, chocolate, wine, and tea. Polyphenols have antimicrobial, anti-inflammatory, and antineoplastic properties. Recent studies suggest that tea polyphenols may be used for reducing sebum production in the skin and for treatment of acne vulgaris. This review examines the evidence for use of topically and orally ingested tea polyphenols against sebum production and for acne treatment and prevention. The PubMed database was searched for studies on tea polyphenols, sebum secretion, and acne vulgaris. Of the 59 studies found, eight met the inclusion criteria. Two studies evaluated tea polyphenol effects on sebum production; six studies examined tea polyphenol effects on acne vulgaris. Seven studies evaluated topical tea polyphenols; one study examined systemic tea polyphenols. None of the studies evaluated both topical and systemic tea polyphenols. Tea polyphenol sources included green tea (six studies) and tea, type not specified (two studies). Overall, there is some evidence that tea polyphenols in topical formulation may be beneficial in reducing sebum secretion and in treatment of acne. Research studies of high quality and with large sample sizes are needed to assess the efficacy of tea polyphenols in topical and oral prevention of acne vulgaris and lipid synthesis by the sebaceous glands.
Cheeseman, H J; Neal, M J
1 The interaction between phenothiazine neuroleptics with tea and coffee was studied in vitro. 2 Filtered infusions of tea and coffee caused precipitation of all the neuroleptics studied. Tea always caused a heavier precipitate than coffee. 3 The constituent or constituents of tea and coffee responsible for precipitating the neuroleptics was not identified. Solutions of caffeine, caffeine citrate and sodium chloride did not form a precipitate with chlorpromazine but precipitates were formed by sodium salicylate, sodium benzoate and trisodium citrate. 4 The interaction between chlorpromazine (CPZ) and tea was studied quantitatively using radiolabelled drug and it was found that the precipitation of [3H]-CPZ with a given quantity of tea was 'saturable'. The proportion of CPZ precipitated by a 'standard cup of tea' was 80% at low doses of the drug (10-40 mg) whilst at high doses (800 mg), the proportion of the drug precipitated was approximately 20%. 5 The interaction was further studied in vivo by the oral administration of tea and CPZ to rats. The cataleptic effect of CPZ was significantly reduced by the simultaneous administration of tea and this was apparently not due to the caffeine present in tea. 6 The results suggest that a substantial proportion of orally administered neuroleptic may be precipitated as a highly insoluble compound if coffee, or more especially tea, is taken close to drug administration. This interaction might affect the absorption of phenothiazines given orally to patients. PMID:7197984
SungHee Kole, Alison; Jones, Heather D; Christensen, Russell; Gladstein, Jay
Kombucha "mushroom'' tea is touted to have medicinal properties. Here, we present a case of hyperthermia, lactic acidosis, and acute renal failure within 15 hours of Kombucha tea ingestion. A 22 year old male, newly diagnosed with HIV, became short of breath and febrile to 103.0F, within twelve hours of Kombucha tea ingestion. He subsequently became combative and confused, requiring sedation and intubation for airway control. Laboratories revealed a lactate of 12.9 mmol/L, and serum creatinine of 2.1 mg/dL. Kombucha tea is black tea fermented in a yeast-bacteria medium. Several case reports exist of serious, and sometimes fatal, hepatic dysfunction and lactic acidosis within close proximity to ingestion. While Kombucha tea is considered a healthy elixir, the limited evidence currently available raises considerable concern that it may pose serious health risks. Consumption of this tea should be discouraged, as it may be associated with life-threatening lactic acidosis.
Muoki, Richard Chalo; Paul, Asosii; Kumar, Sanjay
Drought poses a significant threat to tree plants including tea [Camellia sinensis (L.) O. Kuntze] that yields a popular beverage "tea." Consequence of drought is heat and salt stress, for which data on molecular response in tree species are not available. The present work analyzed drought-responsive subtracted cDNA libraries of tea to identify drought-responsive genes. Temporal and spatial gene expression suggested the involvement of chaperones as one of the major mechanisms to protect the plant against drought-related damages. A common response of thaumatin like protein, chitinase, and late embryogenesis abundant protein3 across four stresses suggests these to be useful targets to generate "drought stress proof" tea.
Phung, Lan Huong; Tran, Trung Kien; Van Quyet, Chu; Phi, Nguyen Thien
The objective of this work is applying adsorption process for separation of polyphenols from extract solution of green tea by-product. The older leaves and stem of green tea tree are collected from Hiep Khanh Tea Company (Hoabinh province, Vietnam). In this study, two kinds of adsorbent (silicagel, active carbon) were applied for the adsorption process in batch stirring vessel. The factors that affected to the process productivity were investigated: temperature, solid/liquid ratio, duration time, stirring speed. The process has been empirically described with statistical models obtained by Design of Experiments. The results indicated that active carbon was verified to offer good adsorption productivity (more than 95%), much more effective than silicagel (with only about 20%). From the model, the most affected factor to the process could be seen as solid/liquid ratio.
Peng, Chuan-yi; Cai, Hui-mei; Zhu, Xiao-hui; Li, Da-xiang; Yang, Yun-qiu; Hou, Ru-yan; Wan, Xiao-chun
The aim of this study was to determine the levels of fluoride in commercial teas and to estimate the contribution of tea consumption to the fluoride recommended daily allowance. A total of 558 tea products in 6 categories, green tea, black tea, oolong tea, pu'er tea, white tea, and reprocessed tea, were collected in the period from 2010 to 2013. The levels of fluoride in infusions of these teas were determined by a fluoride-ion selective electrode. The mean fluoride level in all of the tea samples was 85.16 mg/kg. For each category of tea, the mean fluoride levels were 63.04, 99.74, 52.19, 101.67, 159.78, and 110.54 mg/kg for green tea, black tea, white tea, pu'er tea, oolong tea, and reprocessed tea, respectively. The fluoride content of tea from 4 tea zones in descending order were Southern tea zone (111.39 mg/kg) > Southwest tea zone (78.78 mg/kg) > Jiangnan tea zone (71.73 mg/kg) > Jiangbei tea zone (64.63 mg/kg). These areas produced teas with lower fluoride levels than available foreign-produced tea (161.11 mg/kg). The mean chronic daily intake (CDI) was 0.02 mg/(kg•day) or 1.27 mg/kg. Generally, consuming tea from these 6 categories does not result in the intake of excessive amounts of fluoride for the general population.
Borresen, B.A.; Marken, A.V.
Energy quality relates to energy supply temperatures. Instead of the exergy term, a TEA curve was introduced for evaluating the planned 100 GWh district heating system of Fornebu, outside Oslo. The questions that were raised when analyzing the energy system were: (1) how could one make a design that improves the use of low temperature energy? (2) is a design with low flow rate, i.e., low pipeline costs, compatible with the use of low temperature energy? (3) can one visualize the quality of the energy used through the distributed temperatures and the corresponding quantity of energy? A spreadsheet analysis tool for the TEA curve was implemented, and used for the heating plant design and optimization at Fornebu. The paper presents the TEA curve and shows how evaluations may be done. Different design temperatures ranging from 60 C/50 C to 110 C/40 C are included in the discussion. The main findings are: The TEA curve demonstrates clearly the use of energy quality; Avoid shunting, utilize the available high temperatures when possible; and A 75 C/40 C design improves the level of energy use compared to a 60 C/50 C design.
Hu, Yong-guang; Li, Ping-ping; Mu, Jian-hua; Mao, Han-ping; Wu, Cai-cong; Chen, Bin
To monitor tea tree growth and nitrogen nutrition in tea leaves, visible-near infrared spectroscopy was used to determine total nitrogen content. One hundred eleven fresh tea leaves of different nitrogen levels were sampled according to different tea type, plant age, leaf age, leaf position and soil nutrients, which covered a wide range of nitrogen content. Visible-near infrared reflectance spectra were scanned under the sunlight with a portable spectroradiometer (ASD FieldSpec 3) in field. The software of NIRSA developed by Jiangsu University was used to establish the calibration models and prediction models, which included spectra data editing, preprocessing, sample analysis, spectrogram comparison, calibration model and prediction model, analysis reporting and system configuration Eighty six samples were used to establish the calibration model with the preprocessing of first/second-order derivative plus moving average filter and the algorithm of PLS regression, stepwise regression, principal component regression, PLS regression plus artificial neural network and so on The result shows that the PLS regression calibration model with 7 principal component factors after the preprocessing of first-order derivative plus moving average filter is the best and correspondingly the root mean square error of calibration is 0. 973. Twenty five unknown samples were used to establish the prediction model and the correlation coefficient between predicted values and real values is 0.8881, while the root mean square error of prediction is 0. 130 4 with the mean relative error of 4.339%. Therefore, visible-near infrared spectroscopy has a huge potential for the determination of total nitrogen content in fresh tea leaves in a rapid and nondestructive way. Consequently, the technique can be significant to monitoring the tea tree growth and fertilization management.
Fazakerley, Andrew; Samara, Marilia; Hancock, Barry; Wicks, Robert; Moore, Tom; Rust, Duncan; Jones, Jonathan; Saito, Yoshifumi; Pollock, Craig; Owen, Chris; Rae, Jonny
Turbulence Heating ObserveR (THOR) is the first mission ever flown in space dedicated to plasma turbulence. The Turbulence Electron Analyser (TEA) will measure the plasma electron populations in the mission's Regions of Interest. It will collect a 3D electron velocity distribution with cadences as short as 5 ms. The instrument will be capable of measuring energies up to 30 keV. TEA consists of multiple electrostatic analyser heads arranged so as to measure electrons arriving from look directions covering the full sky, i.e. 4 pi solid angle. The baseline concept is similar to the successful FPI-DES instrument currently operating on the MMS mission. TEA is intended to have a similar angular resolution, but a larger geometric factor. In comparison to earlier missions, TEA improves on the measurement cadence. For example, MMS FPI-DES routinely operates at 30 ms cadence. The objective of measuring distributions at rates as fast as 5 ms is driven by the mission's scientific requirements to resolve electron gyroscale size structures, where plasma heating and fluctuation dissipation is predicted to occur. TEA will therefore be capable of making measurements of the evolution of distribution functions across thin (a few km) current sheets travelling past the spacecraft at up to 600 km/s, of the Power Spectral Density of fluctuations of electron moments and of distributions fast enough to match frequencies with waves expected to be dissipating turbulence (e.g. with 100 Hz whistler waves). A novel capability to time tag individual electron events during short intervals for the purposes of ground analysis of wave-particle interactions is also planned.
Kawarai, Taketo; Narisawa, Naoki; Yoneda, Saori; Tsutsumi, Yoshiaki; Ishikawa, Jun; Hoshino, Yasutaka; Senpuku, Hidenobu
Streptococcus mutans, a gram-positive oral bacterium, has been identified as one of the principal etiological agents of human dental caries. To clarify the nature of the difference anti-biofilm effect against S. mutans between Assam tea from Camellia sinensis var. assamica, partially fermented, and green tea from Camellia sinensis, non-fermented, active agents from the teas were purified. Effects of Assam tea and green tea samples on biofilm were assessed by using the conventional titer plate method and the human saliva-coated hydroxyapatite discs. The purification and identification of inhibitors were performed by using ultrafiltration with centrifugal filter devices and high performance liquid chromatography. Assam tea has stronger biofilm inhibition activity against S. mutans than green tea. A substance of <10kDa in mass in Assam tea had a high concentration of galloylated catechins and a stronger biofilm inhibiting activity than green tea. In contrast, substances >10kDa in mass from green tea included higher concentrations of polysaccharides composed of galacturonic acid, such as pectin, that enhance biofilm formation. The higher concentrations of galloylated catechins in Assam tea may assist in prevention of dental caries, whereas in green tea, this mode of inhibition was likely offset by the presence of pectin. Purification of catechins in partially fermented Assam tea with lower-molecular-weight polysaccharide than pectin may be useful for developing oral care products such as toothpaste and oral care gel pastes. Copyright © 2016 Elsevier Ltd. All rights reserved.
Jayabalan, Rasu; Marimuthu, Subbaiya; Thangaraj, Periyasamy; Sathishkumar, Muthuswamy; Binupriya, Arthur Raj; Swaminathan, Krishnaswami; Yun, Sei Eok
Kombucha tea is sugared black tea fermented with a consortium of acetic acid bacteria and yeasts (tea fungus) for 14 days. The tea tastes slightly sweet and acidic. The formation of tea fungal biofilms during storage is a big problem when kombucha tea is being stored and commercialized. Various thermal treatments have been tried for long-term storage of kombucha tea. The present study revealed the influence of heat on the biochemical constituents and the free radical scavenging properties of kombucha tea. Heat treatment at 60, 65, and 68 degrees C for 1 min controlled biofilm formation in kombucha tea without changing its clarity, taste, and flavor. However, tea polyphenols and black tea quality parameters showed varying stability during the storage period. A decrease in free radical scavenging properties was also found during the storage period. Because the biological activities of kombucha tea depended on the biochemical constituents, it was concluded that heat treatment was not a suitable method for kombucha tea preservation.
Yuan, Jian-Min; Sun, Canlan; Butler, Lesley M
Experimental studies have consistently shown the inhibitory activities of tea extracts on tumorigenesis in multiple model systems. Epidemiological studies, however, have produced inconclusive results in humans. A comprehensive review was conducted to assess the current knowledge on tea consumption and risk of cancers in humans. In general, consumption of black tea was not associated with lower risk of cancer. High intake of green tea was consistently associated with reduced risk of upper gastrointestinal tract cancers after sufficient control for confounders. Limited data support a protective effect of green tea on lung and hepatocellular carcinogenesis. Although observational studies do not support a beneficial role of tea intake on prostate cancer risk, phase II clinical trials have demonstrated an inhibitory effect of green tea extract against the progression of prostate pre-malignant lesions. Green tea may exert beneficial effects against mammary carcinogenesis in premenopausal women and recurrence of breast cancer. There is no sufficient evidence that supports a protective role of tea intake on the development of cancers of the colorectum, pancreas, urinary tract, glioma, lymphoma, and leukemia. Future prospective observational studies with biomarkers of exposure and phase III clinical trials are required to provide definitive evidence for the hypothesized beneficial effect of tea consumption on cancer formation in humans.
Khan, Naghma; Mukhtar, Hasan
Tea, next to water is the cheapest beverage humans consume. Drinking the beverage tea has been considered a health-promoting habit since ancient times. The modern medicinal research is providing a scientific basis for this belief. The evidence supporting the health benefits of tea drinking grows stronger with each new study that is published in the scientific literature. Tea plant Camellia sinensis has been cultivated for thousands of years and its leaves have been used for medicinal purposes. Tea is used as a popular beverage worldwide and its ingredients are now finding medicinal benefits. Encouraging data showing cancer-preventive effects of green tea from cell-culture, animal and human studies have emerged. Evidence is accumulating that black tea may have similar beneficial effects. Tea consumption has also been shown to be useful for prevention of many debilitating human diseases that include maintenance of cardiovascular and metabolic health. Various studies suggest that polyphenolic compounds present in green and black tea are associated with beneficial effects in prevention of cardiovascular diseases, particularly of atherosclerosis and coronary heart disease. In addition, anti-aging, antidiabetic and many other health beneficial effects associated with tea consumption are described. Evidence is accumulating that catechins and theaflavins, which are the main polyphenolic compounds of green and black tea, respectively, are responsible for most of the physiological effects of tea. This article describes the evidences from clinical and epidemiological studies in the prevention of chronic diseases like cancer and cardiovascular diseases and general health promotion associated with tea consumption. PMID:23448443
Xu, Shengjun; Bai, Zhihui; Jin, Bo; Xiao, Runlin; Zhuang, Guoqiang
Wastewater from the sweet potato starch industry is a large source of nutrient-rich substrates. We assessed whether this wastewater could be used to produce Paenibacillus polymyxa biofertilizer for foliar application to tea trees. Using the central composite design methods we experientially determined that the optimal culture conditions for P. polymyxa were pH, 6.5; temperature, 29.0°C; and incubation time, 16 h. Under these conditions, a maximum biomass of 9.7 × 109 cfu/mL was achieved. We then conducted a yearlong field investigation to determine the effect of P. polymyxa biofertilizer on the growth of tea plants (Camellia sinensis). Tea yield, quantity of water extract, and tea polyphenol levels were significantly higher after foliar application of the biofertilizer compared to that in the controls by an average of 16.7%, 6.3%, and 10.4%, respectively. This approach appears to be technically feasible for organic tea production, and is an environmentally friendly way to utilize wastewater. PMID:24576979
Xu, Shengjun; Bai, Zhihui; Jin, Bo; Xiao, Runlin; Zhuang, Guoqiang
Wastewater from the sweet potato starch industry is a large source of nutrient-rich substrates. We assessed whether this wastewater could be used to produce Paenibacillus polymyxa biofertilizer for foliar application to tea trees. Using the central composite design methods we experientially determined that the optimal culture conditions for P. polymyxa were pH, 6.5; temperature, 29.0 °C; and incubation time, 16 h. Under these conditions, a maximum biomass of 9.7 × 10(9) cfu/mL was achieved. We then conducted a yearlong field investigation to determine the effect of P. polymyxa biofertilizer on the growth of tea plants (Camellia sinensis). Tea yield, quantity of water extract, and tea polyphenol levels were significantly higher after foliar application of the biofertilizer compared to that in the controls by an average of 16.7%, 6.3%, and 10.4%, respectively. This approach appears to be technically feasible for organic tea production, and is an environmentally friendly way to utilize wastewater.
Muthu, Manikandan; Gopal, Judy; Min, Shang Xiao; Chun, Sechul
The feasibility of utilizing the antimicrobial activity of naturally available teas was studied. Eleven teas including 2 green teas and 9 other traditional Korean mixed teas were tested for their antimicrobial properties. Antibacterial and antifungal properties were assessed. The results showed that green teas possessed significant antifungal and antibacterial properties, while most of the mixed teas showed some amount of antifungal activity and almost insignificant antibacterial properties. Confocal microscopic imaging revealed mycelial damage as well as attack on sporophores rather than spores/spore germination to be the reason behind the antifungal activity. EGCG was identified as the crucial catechin for antimicrobial activity. The study confirmed that green tea had a clear edge over the traditional mixed teas when it comes to antimicrobial activity.
Students love outdoor activities and will love them even more when they build confidence in their tree identification and measurement skills. Through these activities, students will learn to identify the major characteristics of trees and discover how the pace--a nonstandard measuring unit--can be used to estimate not only distances but also the…
Students love outdoor activities and will love them even more when they build confidence in their tree identification and measurement skills. Through these activities, students will learn to identify the major characteristics of trees and discover how the pace--a nonstandard measuring unit--can be used to estimate not only distances but also the…
Center for Environmental Study, Grand Rapids, MI.
Tree Amigos is a special cross-cultural program that uses trees as a common bond to bring the people of the Americas together in unique partnerships to preserve and protect the shared global environment. It is a tangible program that embodies the philosophy that individuals, acting together, can make a difference. This resource book contains…
Jiang, Heyuan; Engelhardt, Ulrich H; Thräne, Claudia; Maiwald, Beate; Stark, Janina
An UHPLC method for the determination of flavonol glycosides (FOG) from green and oolong tea vs. black tea has been developed for the first time. Sample clean-up method by means of polyamide column chromatography was optimized with multiple-step elution. Using UHPLC and HPLC with gradient elution and photodiode array detection, eighteen FOG compounds were determined with the aid of electrospray tandem mass spectrometry. These FOG compounds were qualified on both UHPLC and HPLC, and this UHPLC method successfully separated rutin (quercetin-3-O-rutinoside) and K-grg (kaempferol-3-O-glucorhamnoglucoside) while conventional HPLC method did not. The total amounts of FOG compounds in the tea samples were 2.32-5.67g/kg dry weight (calculated as aglycones), and there is no significant difference for the total FOG content among green tea, oolong tea and black tea. However, kaempferol glycosides are more abundant in green teas, while oolong tea has more quercetin and myricetin glycosides. In black tea quercetin glycosides were most abundant. Copyright © 2015 Elsevier Ltd. All rights reserved.
Xu, Xuan; Luo, Xiaofeng; Chen, Zhaoxing; Li, Qinyu; Chen, Jianjing; Luo, Yifan
The effect factor of extraction of tea polysaccharide was investigated with orthogonal test. The effects of extraction conditions on yield, purity of tea polysaccharide and cost of extraction were discussed. The results show that the optimum conditions for extracting tea polysaccharide from green tea are as follows: extraction time is 30 minutes with water at 95 degrees C, extraction times with chloroform is 3, extraction times with CH3COOC2H5 is 1 and concentration of alcohol is 60%.
Jochmann, Nicoline; Lorenz, Mario; Krosigk, Amélie von; Martus, Peter; Böhm, Volker; Baumann, Gert; Stangl, Karl; Stangl, Verena
Consumption of tea has been shown to improve endothelial function. It is assumed that catechins are the tea components responsible for these beneficial effects. In black tea, catechin concentrations are significantly lower than in green tea. The present study was designed to compare green and black tea with regard to amelioration of endothelial function. Endothelial function in response to both teas was assessed in bovine aortic endothelial cells (BAEC) and rat aortic rings. To elucidate whether these findings are also applicable to humans, flow-mediated dilation (FMD) and nitro-mediated dilation (NMD) were assessed by ultrasound in twenty-one healthy women before and 2 h after consumption of green and black tea (2 h of FMD and NMD), in comparison with water (control). In BAEC, green and black tea significantly increased endothelial NO synthase activity to the same extent. Similarly, both teas induced comparable endothelial-dependent vasodilation in rat aortic rings. In human subjects, ingestion of green and black tea led to significant increases in FMD: from 5.4 (sd 2.3) to 10.2 (sd 3) % (baseline-adjusted difference (BAD) for 2 h of FMD, green tea v. water: 5.0 (95 % CI 3.0, 7.0) %; P < 0.001) and from 5 (sd 2.6) to 9.1 (sd 3.6) % (BAD for 2 h of FMD, black tea v. water: 4.4 (95 % CI 2.3, 6.5) %; P < 0.001), respectively. The increase in FMD was not significantly different between the two tea preparations (BAD for 2 h of FMD, green tea v. black tea: 0.66 (95 % CI - 0.76, 2.09) %; P = 0.36). NMD did not vary between any of the groups. In conclusion, green and black tea are equally effective in improving endothelial function.
Joshi, Robin; Rana, Ajay; Gulati, Ashu
Recently anthocyanin-rich purple tea varieties have been developed. The quality of these new purple tea varieties developed in Kangra valley was assessed, and compared with the quality of tea from standard Kangra clone. Purple tea shoots (PL) recorded higher amount of polyphenols compared to standard green tea shoot (GL) while epigallocatechin gallate (EGCG) recorded higher levels in GL. Higher levels of theaflavins were recorded in orthodox black tea from purple shoots (BTP) compared to black tea (BT) made from green shoots. Both theanine and caffeine recorded higher levels in GL. Volatile flavour profiles of these teas showed qualitative and quantitative differences. Aroma extract dilution assay showed higher dilution factors in BTP than BT. Orthodox teas from purple shoots exhibited higher antioxidant activity compared to standard black tea. Strong correlation of total quality scores with aroma and infusion colour was observed. Tea from anthocyanin-rich cultivars can become specialty teas with high antioxidant activity.
Han, L K; Takaku, T; Li, J; Kimura, Y; Okuda, H
Oolong tea is traditionally reported to have anti-obesity and hypolipidaemic effects. The present study was performed to clarify whether oolong tea prevented obesity induced in mice by the oral administration of a high-fat diet for 10 weeks. High-fat diet-induced obese mice were treated with oolong tea for 10 weeks. The effects of various active fractions isolated from oolong tea on noradrenaline-induced lipolysis were examined with isolated fat cells and a cell-free system consisting of lipid droplets and hormone-sensitive lipase (HSL). The mean food consumption was not significantly different between high-fat diet-treated mice and high-fat plus oolong tea diet-treated mice. Oolong tea prevented the obesity and fatty liver induced by a high-fat diet. A water extract of oolong tea enhanced noradrenaline-induced lipolysis, and the active substance was identified as caffeine. Caffeine enhanced noradrenaline-induced lipolysis in fat cells without a concomitant increase in HSL activity and also accelerated the hormone-induced lipolysis in a cell-free system consisting of lipid droplets and HSL, but not in the cell-free system with sonicated lipid droplets and HSL. Oolong tea extract inhibited pancreatic lipase activity. It was demonstrated that the anti-obesity effects of oolong tea in high-fat diet-treated mice might be due partly to the enhancing effect of caffeine isolated from oolong tea on noradrenaline-induced lipolysis in adipose tissue, and to the inhibitory action of some other substance in oolong tea on pancreatic lipase activity. Caffeine was found to enhance lipolysis through acting on lipid droplets but not on HSL. The results suggest that oolong tea may be an effective crude drug for the treatment of obesity and fatty liver caused by a high-fat diet.
Dutta, Ritaban; Kashwan, K R; Bhuyan, M; Hines, E L; Gardner, J W
In this paper we have used a metal oxide sensor (MOS) based electronic nose (EN) to analyze five tea samples with different qualities, namely, drier month, drier month again over-fired, well fermented normal fired in oven, well fermented overfired in oven, and under fermented normal fired in oven. The flavour of tea is determined mainly by its taste and smell, which is generated by hundreds of Volatile Organic Compounds (VOCs) and Non-Volatile Organic Compounds present in tea. These VOCs are present in different ratios and determine the quality of the tea. For example Assamica (Sri Lanka and Assam Tea) and Assamica Sinesis (Darjeeling and Japanese Tea) are two different species of tea giving different flavour notes. Tea flavour is traditionally measured through the use of a combination of conventional analytical instrumentation and human or ganoleptic profiling panels. These methods are expensive in terms of time and labour and also inaccurate because of a lack of either sensitivity or quantitative information. In this paper an investigation has been made to determine the flavours of different tea samples using an EN and to explore the possibility of replacing existing analytical and profiling panel methods. The technique uses an array of 4 MOSs, each of, which has an electrical resistance that has partial sensitivity to the headspace of tea. The signals from the sensor array are then conditioned by suitable interface circuitry. The data were processed using Principal Components Analysis (PCA), Fuzzy C Means algorithm (FCM). We also explored the use of a Self-Organizing Map (SOM) method along with a Radial Basis Function network (RBF) and a Probabilistic Neural Network classifier. Using FCM and SOM feature extraction techniques along with RBF neural network we achieved 100% correct classification for the five different tea samples with different qualities. These results prove that our EN is capable of discriminating between the flavours of teas manufactured under
Qiao, Jinping; Kong, Xiangyi; Kong, Aiying; Han, Mei
Tea is an infusion of the leaves of the Camellia sinensis plant and is the most widely consumed beverage in the world after water. The main chemical components in teas are phenolic compounds (tea polyphenols, mainly tea catechins). A large number of in vitro and in vivo scientific studies have supported that the tea polyphenols can provide a number of health benefits such as, reducing the incidence of coronary heart disease, diabetes and cancer. Recently, tea polyphenols have proven highly attractive as lead compounds for drug discovery programs. A clear understanding of chemistry, stability, pharmacokinetics and metabolic fate of tea will be significant to elucidate many medicinal effects by biochemical theory and pharmaceutical development. This article reviews the current literature on the pharmacoknetics and biotransformation of tea catechins. The half-lives of tea polyphenols are 2-4h and their absorption and elimination are rapid in humans. The peak times (tmax) are 1 and 3 h after oral administration and the peak plasma concentrations are low μM range. It has been reported that catechins are easily metabolized by enzyme and microbe, and the main metabolic pathways are methylation, glucuronidation, sulfation, ring-fission metabolism, and so on. The information is important to discuss some of the challenges and benefits of pursuing this family of compounds for drug discovery.
Hayat, Khizar; Iqbal, Hira; Malik, Uzma; Bilal, Uzma; Mushtaq, Sobia
The recent convention of introducing phytochemicals to support the immune system or combat diseases is a centuries' old tradition. Nutritional support is an emerging advancement in the domain of diet-based therapies; tea and its constituents are one of the significant components of these strategies to maintain the health and reduce the risk of various malignancies. Tea is the most frequently consumed beverage worldwide, besides water. All the three most popular types of tea, green (unfermented), black (fully fermented), and oolong (semifermented), are manufactured from the leaves of the plant Camellia sinensis. Tea possesses significant antioxidative, anti-inflammatory, antimicrobial, anticarcinogenic, antihypertensive, neuroprotective, cholesterol-lowering, and thermogenic properties. Several research investigations, epidemiological studies, and meta-analyses suggest that tea and its bioactive polyphenolic constituents have numerous beneficial effects on health, including the prevention of many diseases, such as cancer, diabetes, arthritis, cardiovascular disease (CVD), stroke, genital warts, and obesity. Controversies regarding beneficialts and risks of tea consumption still exist but the limitless health-promoting benefits of tea outclass its few reported toxic effects. However, with significant rise in the scientific investigation of role of tea in human life, this review is intended to highlight the beneficial effects and risks associated with tea consumption.
van het Hof, K H; Kivits, G A; Weststrate, J A; Tijburg, L B
To assess the blood concentration of catechins following green or black tea ingestion and the effect of addition of milk to black tea. Twelve volunteers received a single dose of green tea, black tea and black tea with milk in a randomized cross-over design with one-week intervals. Blood samples were drawn before and up to eight hours after tea consumption. The study was performed at the Unilever Research Vlaardingen in The Netherlands. Twelve healthy adult volunteers (7 females, 5 males) participated in the study. They were recruited among employees of Unilever Research Vlaardingen. Green tea, black tea and black tea with semi-skimmed milk (3 g tea solids each). Consumption of green tea (0.9 g total catechins) or black tea (0.3 g total catechins) resulted in a rapid increase of catechin levels in blood with an average maximum change from baseline (CVM) of 0.46 micromol/l (13%) after ingestion of green tea and 0.10 micromol/l (13%) in case of black tea. These maximum changes were reached after (mean (s.e.m.)) t=2.3 h (0.2) and t=2.2 h (0.2) for green and black tea respectively. Blood levels rapidly declined with an elimination rate (mean (CVM)) of t1/2=4.8 h (5%) for green tea and t1/2=6.9 h (8%) for black tea. Addition of milk to black tea (100 ml in 600 ml) did not significantly affect the blood catechin levels (areas under the curves (mean (CVM) of 0.53 h. micromol/l (11%) vs 0.60 h. micromol/l (9%) for black tea and black tea with milk respectively. Catechins from green tea and black tea are rapidly absorbed and milk does not impair the bioavailability of tea catechins.
Wu, Chunyan; Xu, Hairong; Héritier, Julien; Andlauer, Wilfried
A standardised profiling method based on high performance liquid chromatography combined with ultraviolet (UV) and mass spectrometric detection (MS) was established to analyse the phenolic compounds of selected tea varieties used for manufacturing of green, black and oolong teas. The composition and content of 24 tea constituents were analysed, including catechins, flavonol and flavones glycosides, phenolic acids and purine alkaloids. Each tea variety had a unique chemical profile. The compositions of catechins were lower in the tea varieties for green tea manufacturing, while the content of myricetin glycosides was the lowest in the tea variety for oolong tea manufacturing. The content of individual phenolic compounds in the selected tea varieties is highly variable. However, the content of total catechins is proposed to be helpful to classify tea according to the future application as non fermented green and fermented oolong or black tea.
Conti, Barbara; Flamini, Guido; Cioni, Pier Luigi; Ceccarini, Lucia; Macchia, Mario; Benelli, Giovanni
In latest years, the importance of the Melaleuca alternifolia essential oil (EO) has been greatly empathised due to its anti-microbial and anti-inflammatory effects, as well as to its toxic properties towards many arthropods of great medical and veterinary importance. In this research, the EO extracted from aerial parts of M. alternifolia was evaluated for its toxicity against larvae of the most invasive mosquito worldwide, Aedes albopictus (Diptera: Culicidae), and towards adults of the water flea, Daphnia magna (Cladocera: Crustacea), a non-target aquatic organism that share the same ecological niche of A. albopictus. The chemical composition of M. alternifolia EO was investigated by GC-MS analysis. Tea tree EO was mainly composed by oxygenated monoterpenes, with 1,8-cineole as the major constituent. M. alternifolia EO exerted toxic activity against A. albopictus larvae, with a LC50 = 267.130 ppm. However, this EO had a remarkable acute toxicity also towards adults of the non-target arthropod D. magna, with a LC50 = 80.636 ppm. This research provide useful information for the development of newer and safer mosquito control tools, highlighting that the non-target effects against aquatic organisms that share the same ecological niche of A. albopictus larvae are crucial in the development of ecofriendly mosquito control strategies. Further research is needed to investigate the chronic and/or reproductive toxicity of M. alternifolia EO both towards target and non-target aquatic arthropods.
Tea, one of the most commonly consumed beverages in the world, has many health benefits. Tea polyphenols support health by promoting antioxidant enzymes, promoting apoptosis, preventing angiogenesis, and modulating epigenetic change. Considerable basic science and epidemiologic evidence supports the regular consumption of this tasty, inexpensive beverage. PMID:20396424
Mukhtar, H; Ahmad, N
The concept of prevention of cancer using naturally occurring substances that could be included in the diet consumed by the human population is gaining increasing attention. Tea, next to water, is the most popularly consumed beverage in the world and it is grown in about 30 countries. Abundant data, amassed from several laboratories around the world in the last ten years, provided convincing evidence that polyphenolic antioxidants present in tea afford protection against cancer risk in many animal-tumor bioassay systems. The epidemiological studies, though inconclusive, have also suggested that the consumption of tea is associated with a lowered risk of cancer. Much of this work has been done on green tea; less is known about black tea. Green tea contains many polyphenolic antioxidants, and (-)-epigallocatechin-3-gallate (EGCG) is the key polyphenolic antioxidant believed to be responsible for most of the cancer chemopreventive properties of green tea. This review will discuss these effects and the molecular mechanisms associated with the biological response to green-tea polyphenols.
Clark, Julie; You, Ming
Tea is the second only to water as the most consumed beverage in the world. Both green and black teas have been studied for their health benefits for a variety of diseases, particularly cancer. Lung cancer is the predominant cause of cancer mortality in developed countries. Smokers' risk of lung cancer is 20 times that of persons who have never smoked. Epidemiological studies on the cancer-preventive effects of tea produce inconsistent results, which could in part be attributed to the lack of a universal standard for tea preparations. However, most animal studies indicate that tea has strong chemopreventive effects against lung tumorigenesis. The reported mechanisms for chemopreventive activity of green tea are antioxidation, induction of phase II enzymes, inhibition of TNFalpha expression and release, inhibition of cell proliferation, and induction of apoptosis. Cell cycle arrest and apoptosis induced by green tea are probably the two most significant factors. Future studies are needed to determine how green tea affects the genes associated with cell cycle regulation and apoptosis during the mouse lung carcinogenesis process.
Vuong, Quan V; Golding, John B; Nguyen, Minh; Roach, Paul D
Tea is a major source of catechins, which have become well known for their antioxidant potential. Numerous human, animal, and in vitro studies have linked tea catechins with prevention of certain types of cancers, reduction of the risks for obesity, diabetes, and cardiovascular disease, and improvement of the immune system. Tea catechins are widely used in various neutraceuticals, pharmaceuticals, and cosmetics for either enhancing product shelf-life or for enhancing human health. Thus, the demand for catechins has increased considerably. Catechins have been extracted and isolated from tea leaves by numerous methods through several steps including: treatment of the tea leaves, extraction of catechins from teas into solvents, isolation of catechins from other extracted components, and drying the preparations to obtain catechin extracts in a powder form. This paper outlines the physical and chemical properties of the tea catechins and reviews the extraction steps of the various extraction methods, as a basis to improve and further develop the extraction and isolation of the tea catechins.
Recently several RICH protypes successfully tested a gaseous TEA photocathode. However, its wire ageing behavior is unknown. In principle, TEA is a more strongly bonded molecule than TMAE, and, as a result, one would expect better wire ageing behavior. This paper explores this question.
Park, Jae-Hyung; Bae, Jae-Hoon; Im, Sung-Soon; Song, Dae-Kyu
Green tea and coffee consumption have been widely popular worldwide. These beverages contain caffeine to activate the central nervous system by adenosine receptor blockade, and due to the caffeine, addiction or tolerance may occur. In addition to this caffeine effect, green tea and coffee consumption have always been at the center of discussions about human health, disease, and longevity. In particular, green tea catechins are involved in many biological activities such as antioxidation and modulation of various cellular lipid and proteins. Thus, they are beneficial against degenerative diseases, including obesity, cancer, cardiovascular diseases, and various inflammatory diseases. Some reports also suggest that daily consumption of tea catechins may help in controlling type 2 diabetes. However, other studies have reported that chronic consumption of green tea may result in hepatic failure, neuronal damage, and exacerbation of diabetes, suggesting that interindividual variations in the green tea effect are large. This review will focus on the effect of green tea catechins extracted from the Camellia sinensis plant on type 2 diabetes and obesity, and the possible mechanistic explanation for the experimental results mainly from our laboratory. It is hoped that green tea can be consumed in a suitable manner as a supplement to prevent the development of type 2 diabetes and obesity.
Yang, Chung S; Liao, Jie; Yang, Guang-yu; Lu, Gary
Tea and tea constituents have been shown by different investigators to inhibit lung tumorigenesis in different animal model systems. This includes lung tumorigenesis in A/J mice induced by 4-(methylnitrosamino)-1-(3pyridyl)-1-butanone (NNK), N-nitrosodiethylamine, benzo[a]pyrene, N-nitrosomethylurea, or cisplatin. Inhibition of lung tumorigenesis has also been demonstrated in C3H mice treated with N-nitrosodiethylamine. In most of these experiments, reduction in tumor number and tumor size has been observed in the tea-treated group, and in some experiments, decreased tumor incidence has also been observed. The green tea constituent, epigallocatechin-3-gallate (EGCG), and the black tea constituent, theaflavins, have also been shown to be effective. Black tea preparations have been shown to reduce the incidence and number of spontaneously generated lung adenocarcinomas and rhabdomyosarcoma in A/J mice, as well as inhibit the progression of lung adenoma to adenocarcinoma. The mechanisms for the inhibitory action have not been well elucidated. It may be related to the antiproliferative, proapoptotic, and antiangiogenic activities of tea constituents that have been demonstrated in some experiments. These activities may be a result of the inhibition of key protein kinases involved in signal transduction and cell cycle regulation. Tea catechins, such as EGCG, have been suggested to be the effective components. However, a study suggests that caffeine is the key effective constituent for the inhibitory activity of lung tumorigenesis in Fisher 344 rats by black tea. In many of the experiments, tea consumption resulted in the reduction of body fat and body weight; these factors may also contribute to the inhibition of tumorigenesis.
Ohishi, Tomokazu; Goto, Shingo; Monira, Pervin; Isemura, Mamoru; Nakamura, Yoriyuki
Green tea has been shown to have beneficial effects against a variety of diseases such as cancer, obesity, diabetes, cardiovascular disease, and neurodegenerative diseases. Through cellular, animal, and human experiments, green tea and its major component, epigallocatechin-3-gallate (EGCG) have been demonstrated to have anti-inflammatory effects. Our previous findings have indicated that green tea and EGCG suppress the gene and/or protein expression of inflammatory cytokines and inflammation-related enzymes. Using bibliographic databases, particularly PubMed (provided by the http://www.ncbi.nlm.nih.gov/pubmed, US National Library of Medicine, National Institutes of Health, United States), we examined the potential usefulness of green tea/EGCG for the prevention and treatment of inflammatory diseases in human clinical and epidemiological studies. We also reviewed results from cellular and animal experiments and proposed action mechanisms. Most of the results from the human studies indicated the beneficial effects of green tea and tea catechins against inflammatory diseases. The cellular and animal studies also provided evidence for the favorable effects of green tea/EGCG. These results are compatible with our previous findings and can be largely explained by a mechanism wherein green tea/EGCG acts as an antioxidant to scavenge reactive oxygen species, leading to attenuation of nuclear factor-κB activity. Since green tea and EGCG have multiple targets and act in a pleiotropic manner, we may consider their usage to improve the quality of life in patients with inflammatory disease. Green tea and EGCG have beneficial health effects and no severe adverse effects; however, care should be taken to avoid overdosage, which may induce deleterious effects including hepatic injury. Copyright© Bentham Science Publishers; For any queries, please email at firstname.lastname@example.org.
Tuckerella japonica appears strongly associated with tea (Camellia sinensis (L.) Kuntze., Theaceae) and, due to certain cultural practices in tea production, has in fact become a world traveller, accompanying the greatly coveted tea plant as it spread across the planet. The history of tea productio...
Kilel, E C; Faraj, A K; Wanyoko, J K; Wachira, F N; Mwingirwa, V
The Kenyan tea industry wishes to diversify its tea products, and in line with this, anthocyanin - rich teas were developed at the Tea Research Foundation of Kenya. These teas have purple-coloured leaves and the green colour is masked. In total, 12 accessions of the purple leaf coloured teas and 2 standard tea varieties were studied. Clones Hanlu and Yabukita are Chinese and Japanese tea varieties, respectively, known for good green tea, and they were used as reference standards. Little if any research had been done to characterize the quality of these purple leaf coloured teas and this study investigated their total polyphenols (TPP), catechins, caffeine, gallic acid and theanine. These are the major green tea quality parameters. Results showed that the new Kenyan tea clones had higher total polyphenols than had the reference standard tea varieties, which had 17.2% and 19.7% while the lowest among the Kenyan clones was 20.8%. On catechin quality index, K-purple and TRFK 91/1 showed high index values of 15.9 and 13.3, respectively, while clones TRFK 83/1 and 73/5 showed low index values of 0.74 and 1.0, respectively. Hanlu had the highest caffeine level with 2.42% while clones TRFK KS 3, TRFK KS 2 and TRFK 83/1 had relatively high caffeine levels among the purple leaf coloured teas, with 2.33%, 2.22% and 2.21%, respectively. Clone TRFK 73/5 had the lowest caffeine content, with 1.16%. Theanine analysis showed that most purple leaf coloured teas had more theanine than had the reference standard clones, except TRFK 83/1 and K-purple, which were lower than the reference standard clones. The implication of the green tea chemical quality parameters is also discussed. It is concluded that all the studied clones/varieties have above the minimum 14% of total polyphenols. Clones K-purple and TRFK 91/1 showed high green tea quality indices with the latter doubling with high levels of theanine; hence its highly recommended for green tea manufacture. Copyright © 2013 Elsevier
Zeng, Lanting; Zhou, Ying; Gui, Jiadong; Fu, Xiumin; Mei, Xin; Zhen, Yunpeng; Ye, Tingxiang; Du, Bing; Dong, Fang; Watanabe, Naoharu; Yang, Ziyin
Indole is a characteristic volatile constituent in oolong tea. Our previous study indicated that indole was mostly accumulated at the turn over stage of oolong tea manufacturing process. However, formation of indole in tea leaves remains unknown. In this study, one tryptophan synthase α-subunit (TSA) and three tryptophan synthase β-subunits (TSBs) from tea leaves were isolated, cloned, sequenced, and functionally characterized. Combination of CsTSA and CsTSB2 recombinant protein produced in Escherichia coli exhibited the ability of transformation from indole-3-glycerol phosphate to indole. CsTSB2 was highly expressed during the turn over process of oolong tea. Continuous mechanical damage, simulating the turn over process, significantly enhanced the expression level of CsTSB2 and amount of indole. These suggested that accumulation of indole in oolong tea was due to the activation of CsTSB2 by continuous wounding stress from the turn over process. Black teas contain much less indole, although wounding stress is also involved in the manufacturing process. Stable isotope labeling indicated that tea leaf cell disruption from the rolling process of black tea did not lead to the conversion of indole, but terminated the synthesis of indole. Our study provided evidence concerning formation of indole in tea leaves for the first time.
Kraujalytė, Vilma; Pelvan, Ebru; Alasalvar, Cesarettin
Various instant teas produced differently from black tea [freeze-dried instant tea (FDIT), spray-dried instant tea (SDIT), and decaffeinated instant tea (DCIT)], were compared for their differences in volatile compounds as well as descriptive sensory analysis (DSA). A total of 63 volatile compounds in all tea samples (eight aldehydes, ten alcohols, nine ketones, five esters, eight acids, ten terpenes/terpenoids, ten furans/furanones, two pyrroles, and one miscellaneous compound) were tentatively identified. Black tea, FDIT, SDIT, and DCIT contained 60, 55, 47, and 40 volatile compounds, respectively. Ten flavour attributes such as after taste, astringency, bitter, caramel-like, floral/sweet, green/grassy, hay-like, malty, roasty, and seaweed were identified. Intensities for a number of flavour attributes (except for caramel-like in SDIT and bitter and after taste in DCIT) were not significantly different (p>0.05) among tea samples. The present study suggests that instant teas can also be used as good alternative to black tea.
Du, Liping; Ma, Lijuan; Qiao, Yang; Lu, Yan; Xiao, Dongguang
Phthalate esters (PAEs), a group of environmental pollutants which are carcinogenic to human body, have been detected in teas. In this work, five PAEs in teas and tea infusions were quantitatively determined by a modified simultaneous distillation extraction (SDE) coupled with gas chromatography-mass spectrometry. After the optimization of SDE, the proposed method afforded a wide range of linearity and high linear regression coefficients with the limits of detection range of 0.24-3.72 μg/kg. The average recoveries were 79.83-116.67% for tea samples and 78.22-101.64% for tea infusions with all the relative standard deviations below 20%. The total content of five PAEs in teas was 1.135-3.734 mg/kg and the total dissolving ratio of five PAEs from tea to infusion was 19.05-28.07% for the selected tea samples. The risk assessment result of all the selected tea samples demonstrated that the population with the habit of drinking tea won't cause risk to human health.
Tang, Naping; Wu, Yuemin; Zhou, Bo; Wang, Bin; Yu, Rongbin
Studies investigating the association of green tea and black tea consumption with lung cancer risk have reported inconsistent findings. To provide a quantitative assessment of this association, we conducted a meta-analysis on the topic. Studies were identified by a literature search in PubMed from 1966 to November 2008 and by searching the reference lists of relevant studies. Summary relative risk (RR) estimates and their corresponding 95% confidence intervals (CIs) were calculated based on random-effects model. Our meta-analysis included 22 studies provided data on consumption of green tea or black tea, or both related to lung cancer risk. For green tea, the summary RR indicated a borderline significant association between highest green tea consumption and reduced risk of lung cancer (RR=0.78, 95% CI=0.61-1.00). Furthermore, an increase in green tea consumption of two cups/day was associated with an 18% decreased risk of developing lung cancer (RR=0.82, 95% CI=0.71-0.96). For black tea, no statistically significant association was observe through the meta-analysis (highest versus non/lowest, RR=0.86, 95% CI=0.70-1.05; an increment of two cups/day, RR=0.82, 95% CI=0.65-1.03). In conclusion, our data suggest that high or an increase in consumption of green tea but not black tea may be related to the reduction of lung cancer risk.
Peng, Chuanyi; Xi, Junjun; Chen, Guijie; Feng, Zhihui; Ke, Fei; Ning, Jingming; Li, Daxiang; Ho, Chi-Tang; Cai, Huimei; Wan, Xiaochun
Brick tea usually contains very high fluoride, which may affect human health. Biosorbents have received much attention for selective removal of fluoride because of low cost, environmental friendliness, and relative safeness. In the present study, a highly selective fluoride tea waste based biosorbent, namely, aluminum (Al) oxide decorated tea waste (Tea-Al), was successfully prepared. The Tea-Al biosorbent was characterized by energy-dispersive spectrometry, Fourier transform infrared spectroscopy, powder X-ray diffraction and X-ray photoelectron spectroscopic analysis. The Tea-Al sample exhibited remarkably selective adsorption for fluoride (52.90%), but a weaker adsorption for other major constituents of brick tea infusion, such as catechins, polyphenols and caffeine, under the same conditions. Fluoride adsorption by Tea-Al for different times obeyed the surface reaction and adsorption isotherms fit the Freundlich model. In addition, the fluoride adsorption mechanism appeared to be an ion exchange between hydroxyl and fluoride ions. Results from this study demonstrated that Tea-Al is a promising biosorbent useful for the removal of fluoride in brick tea infusion. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.
S86-E-5346 (30 September 1997) --- This Electronic Still Camera (ESC) image shows astronaut C. Michael Foale, mission specialist, hydrating tea in the middeck of the Earth-orbiting Space Shuttle Atlantis. Foale, now a STS-86 crew member, has been onboard the Russian Mir Space Station as a cosmonaut guest researcher since mid-May 1997. He was replaced by astronaut David A. Wolf during the STS-86 Atlantis/Mir docking mission. This is the seventh Atlantis/Mir docking mission. This view was taken at 00:35:35 GMT on September 30, 1997.
The tea aphid, Toxoptera aurantii Boyer (Homoptera: Aphididae), is a major pest of the tea plant, Camellia sinensis. Fourteen volatile compounds were identified by GC-MS from air passed over intact tea shoots (ITSV). Electrophysiological and behavioral responses of the winged tea aphids to ITSV as w...
National Audubon Society, New York, NY.
Included are an illustrated student reader, "The Story of Trees," a leaders' guide, and a large tree chart with 37 colored pictures. The student reader reviews several aspects of trees: a definition of a tree; where and how trees grow; flowers, pollination and seed production; how trees make their food; how to recognize trees; seasonal changes;…
National Audubon Society, New York, NY.
Included are an illustrated student reader, "The Story of Trees," a leaders' guide, and a large tree chart with 37 colored pictures. The student reader reviews several aspects of trees: a definition of a tree; where and how trees grow; flowers, pollination and seed production; how trees make their food; how to recognize trees; seasonal changes;…
Rong, Lei; Peng, Li-Juan; Ho, Chi-Tang; Yan, Shou-He; Meurens, Marc; Zhang, Zheng-Zhu; Li, Da-Xiang; Wan, Xiao-Chun; Bao, Guan-Hu; Gao, Xue-Ling; Ling, Tie-Jun
Green tea, oolong tea and black tea were separately introduced to brew three kinds of tea beers. A model was designed to investigate the tea beer flavour character. Comparison of the volatiles between the sample of tea beer plus water mixture (TBW) and the sample of combination of tea infusion and normal beer (CTB) was accomplished by triangular sensory test and HS-SPME GC-MS analysis. The PCA of GC-MS data not only showed a significant difference between volatile features of each TBW and CTB group, but also suggested some key compounds to distinguish TBW from CTB. The results of GC-MS showed that the relative concentrations of many typical tea volatiles were significantly changed after the brewing process. More interestingly, the behaviour of yeast fermentation was influenced by tea components. A potential interaction between tea components and lager yeast could be suggested. Copyright © 2015 Elsevier Ltd. All rights reserved.
Yiannakopoulou, Eugenia C
Aberrant epigenetic alterations in the genome such as DNA methylation play a significant role in cancer development. Green tea catechins have been reported to modulate epigenetic processes. This review aims to synthesize evidence on the modulation of DNA methylation by green tea catechins. Green tea catechins have been reported to reverse DNA methylation of tumor suppressor genes and increase transcription of these genes. Green tea catechins and especially epigallocatechin gallate modulate DNA methylation by attenuating the effect of DNA methyltransferase 1 (DNMT1). However, the exact mechanism of DNMT1 inhibition is not delineated. Suggested mechanisms include direct enzymatic inhibition, indirect enzymatic inhibition, reduced DNMT1 expression and translation. The possible effect of green tea catechins on other pathways of DNA methylation, i.e. methyl-CpG binding domain proteins, has not been investigated. Furthermore, the link between redox properties and epigenetic modulation by green tea catechins has not been defined either. Since green tea catechins are natural compounds with a rather acceptable safety profile, further research on their action as inhibitors of DNA methylation seems worthwhile. © 2015 S. Karger AG, Basel
Reygaert, Wanda C.
Green tea is a popular drink, especially in Asian countries, although its popularity continues to spread across the globe. The health benefits of green tea, derived from the leaves of the Camellia sinensis plant, have been studied for many years. Fairly recently, researchers have begun to look at the possibility of using green tea in antimicrobial therapy, and the potential prevention of infections. The particular properties of catechins found in the tea have shown promise for having antimicrobial effects. There are four main catechins (polyphenols) found in green tea: (-)-epicatechin (EC), (-)-epicatechin-3-gallate (ECG), (-)-epigallocatechin (EGC), and (-)-epigallocatechin-3-gallate (EGCG). Three of these, ECG, EGC, and EGCG have been shown to have antimicrobial effects against a variety of organisms. These catechins have exhibited a variety of antimicrobial mechanisms. The results of studies on the antimicrobial effects of green tea have shown that the potential for preventive and therapeutic purposes is present. Further data collection on studies performed with human consumption during the course of infections, and studies on the occurrence of infections in populations that consume regular amounts of green tea will be necessary to complete the picture of its antimicrobial possibilities. PMID:25191312
Blecic, Jasmina; Harrington, Joseph; Bowman, M. Oliver
We present an open-source Thermochemical Equilibrium Abundances (TEA) code that calculates the abundances of gaseous molecular species. The code is based on the methodology of White et al. and Eriksson. It applies Gibbs free-energy minimization using an iterative, Lagrangian optimization scheme. Given elemental abundances, TEA calculates molecular abundances for a particular temperature and pressure or a list of temperature-pressure pairs. We tested the code against the method of Burrows & Sharp, the free thermochemical equilibrium code Chemical Equilibrium with Applications (CEA), and the example given by Burrows & Sharp. Using their thermodynamic data, TEA reproduces their final abundances, but with higher precision. We also applied the TEA abundance calculations to models of several hot-Jupiter exoplanets, producing expected results. TEA is written in Python in a modular format. There is a start guide, a user manual, and a code document in addition to this theory paper. TEA is available under a reproducible-research, open-source license via https://github.com/dzesmin/TEA.
Yang, Chung S; Wang, Hong
Catechins are widely occurring in our diet and beverages. The cancer-preventive activities of catechins have been extensively studied. Of these, (-)-epigallocatechin-3-gallate (EGCG), the principal catechin in green tea, has received the most attention. The inhibitory activities of tea catechins against carcinogenesis and cancer cell growth have been demonstrated in a large number of laboratory studies. Many mechanisms for modulating cancer signaling and metabolic pathways have been proposed based on numerous studies in cell lines with EGCG, the most active tea catechin. Nevertheless, it is not known whether many of these mechanisms indeed contribute to the anti-cancer activities in animals and in humans. Human studies have provided some results for the cancer preventive activities of tea catechins; however, the activities are not strong. This article reviews the cancer preventive activities and mechanisms of action of tea catechins involving their redox activities, biochemical properties and binding to key enzymes or signal transduction proteins. These mechanisms lead to suppression of cell proliferation, increased apoptosis and inhibition of angiogenesis. The relevance of the proposed mechanisms for cancer prevention are assessed in the light of the situation in vivo. The potential and possible problems in the application of tea and tea-derived products for cancer prevention are discussed.
Kondo, Takahide; Watanabe, Ayaka; Shitara, Hiroshi; Kaburagi, Yasuo; Shibata, Masahisa; Kanda, Noriko; Kurokawa, Chieko; Inoue, Yutaka; Miyazaki, Motonobu; Togawa, Masayuki; Ozawa, Akihito; Uchiyama, Toru; Koizumi, Yutaka; Nakamura, Yoriyuki; Masuda, Shuichi; Maitani, Tamio
The effects of processing to produce various types of tea or infusion on the levels of pesticide residues in tea were investigated for three insecticides (chlorfenapyr, pyrimiphos-methyl, and clothianidin). Tea plants were sprayed with one of the three pesticides and cultivated under cover. The levels of pesticide residues in tea decreased after processing according to the time and temperature of heating, as well as fermentation. Although significant differences were not observed among the three pesticides in the ratio of decreased of pesticide concentration after processing to green tea, clothianidin, which is a neonicotinoid insecticide and has a lower log Pow value, tended to be transferred more than the other two insecticides into infusions. However, no significant difference in the ratios of clothianidin transferred to infusions was observed among green tea with three different leaf sizes.
Wang, Xiujuan; Wang, Dongmei; Li, Jiaxian; Ye, Chuangxing; Kubota, Kikue
Three types of Cocoa tea, green, oolong, and black, were prepared from fresh young leaves of Camellia ptilophylla. Their aroma characteristics were compared by a sensory evaluation with corresponding traditional tea samples made from C. sinensis. The aroma profile of Cocoa green tea was quite different from that of traditional green tea, but fermented Cocoa oolong tea and black tea showed aroma profiles similar to those of traditional oolong tea and black tea. Cocoa green tea contained vanillin as the most abundant aroma constituent. Almost the same aroma compounds of jasmine lactone, indole and monoterpene alcohols, which are known as important aroma constituents in commercial oolong tea and black tea, were identified as the main aroma compounds in the fermented Cocoa tea types. The composition of these aroma compounds well explained the aroma profile of each Cocoa tea. The monoterpene alcohols seemed to be released during fermented tea manufacture, because seventeen glycosides consisting of the aglycons of terpene alcohols were identified in Cocoa tea leaves, and hydrolytic activity of crude enzymes in the p-nitrophenol glycoside substrate was also detected.
Short rotation intensive culture tree plantations have been a major part of biomass energy concepts since the beginning. One aspect receiving less attention than it deserves is harvesting. This article describes an method of harvesting somewhere between agricultural mowing machines and huge feller-bunchers of the pulpwood and lumber industries.
Mark J. Ambrose
Tree mortality is a natural process in all forest ecosystems. However, extremely high mortality also can be an indicator of forest health issues. On a regional scale, high mortality levels may indicate widespread insect or disease problems. High mortality may also occur if a large proportion of the forest in a particular region is made up of older, senescent stands....
Mark J. Ambrose
Tree mortality is a natural process in all forest ecosystems. However, extremely high mortality can also be an indicator of forest health issues. On a regional scale, high mortality levels may indicate widespread insect or disease problems. High mortality may also occur if a large proportion of the forest in a particular region is made up of older, senescent stands....
Mark J. Ambrose
Tree mortality is a natural process in all forest ecosystems. However, extremely high mortality also can be an indicator of forest health issues. On a regional scale, high mortality levels may indicate widespread insect or disease problems. High mortality may also occur if a large proportion of the forests in a region is made up of older, senescent stands.
Wang, Jian; Cheung, Wendy; Leung, Daniel
This paper presents a study on pesticide residue transfer rates (%) from dried tea leaves to brewed tea. In the study, a brewing procedure simulated the preparation of a hot tea drink as in routine. After brewing, pesticide residues were extracted from brewed tea using a method known as QuEChERS (quick, easy, cheap, effective, rugged, and safe). An UHPLC/ESI-MS/MS method was developed and validated to identify and quantify up to 172 pesticides in both tea leaves and brewed tea samples. Quantification was achieved using matrix-matched standard calibration curves with isotopically labeled standards or a chemical analogue as internal standards, and the calibration curves consisted of six points (0.4, 2.0, 8.0, 16.0, 24.0, and 40.0 μg/L equivalent in sample). The method was validated at four concentration levels (4.0, 12, 20.0, and 32.0 μg/L equivalent in sample) using five different brewed tea matrices on two separate days per matrix. Method performance parameters included overall recovery, intermediate precision, and measurement uncertainty, which were evaluated according to a nested experimental design. Approximately, 95% of the pesticides studied had recoveries between 81 and 110%, intermediate precision ≤20%, and measurement uncertainty ≤40%. From a pilot study of 44 incurred tea samples, pesticide residues were examined for their ability to transfer from dried tea leaves to brewed tea. Each sample, both tea leaves and brewed tea, was analyzed in duplicate. Pesticides were found to have different transfer rates (%). For example, imidacloprid, methomyl, and carbendazim had transfer rates of 84.9, 83.4, and 92.4%, respectively.
Yang, Chung S; Li, Guangxun; Yang, Zhihong; Guan, Fei; Chen, Amber; Ju, Jihyeung
Tocopherols (vitamin E) and tea polyphenols have been reported to have cancer preventive activities. Large-scale human trials with high doses of alpha-tocopherol, however, have produced disappointing results. This review presents data showing that - and -tocopherols inhibit colon, lung, mammary and prostate carcinogenesis in animal models, whereas -tocopherol is ineffective in animal and human studies. Possible mechanisms of action are discussed. A broad cancer preventive activity of green tea polyphenols has been demonstrated in animal models, and many mechanisms have been proposed. The cancer preventive activity of green tea in humans, however, has not been conclusively demonstrated and remains to be further investigated.
Yang, Chung S.; Li, Guangxun; Yang, Zhihong; Guan, Fei; Chen, Amber; Ju, Jihyeung
Tocopherols (vitamin E) and tea polyphenols have been reported to have cancer preventive activities. Large-scale human trials with high doses of alpha-tocopherol, however, have produced disappointing results. This review presents data showing that γ- and δ-tocopherols inhibit colon, lung, mammary and prostate carcinogenesis in animal models, whereas α-tocopherol is ineffective in animal and human studies. Possible mechanisms of action are discussed. A broad cancer preventive activity of green tea polyphenols has been demonstrated in animal models, and many mechanisms have been proposed. The cancer preventive activity of green tea in humans, however, has not been conclusively demonstrated and remains to be further investigated. PMID:23403075
Umegaki, Keizo; Sekine, Yuki; Sato, Yoko; Chiba, Tsuyoshi; Sonoda, Masaru
Green tea is thought to be a primary source of folate in the Japanese diet, based on folate content analyzed by a microbiological assay. Green tea also contains high amount of catechins, in particular, epigallocatechin gallate (EGCg), which was demonstrated to be able to inhibit the digestive enzyme activities and microbial growth in the folate assay. In the present study, we examined whether tea catechins interfered with components of the folate assay for green tea. A marked inhibitory effect of EGCg on microbial growth was observed at an inhibitory concentration of higher than 10 μg/mL. Tea catechins without the galloyl moiety did not show an inhibitory effect. EGCg inhibited the activity of the three enzymes used for assay sample preparation at an inhibitory concentration of higher than 750 μg/mL for α-amylase, 1,000 μg/mL for protease, and 50 μg/mL for conjugase. However, with each step of the assay, the actual concentration of EGCg was decreased to below the inhibitory concentration of each analytical step. Lack of influence of EGCg on green tea folate assay was confirmed by an addition of folate standard in tea infusion. These results suggested that tea catechins have no practical impact on folate analysis in green tea, using the general microbiological assay.
Van Dorsten, Ferdi A; Daykin, Clare A; Mulder, Theo P J; Van Duynhoven, John P M
The purpose of this study was to compare the effects of black and green tea consumption on human metabolism. Seventeen healthy male volunteers consumed black tea, green tea, or caffeine in a randomized crossover study. Twenty-four-hour urine and blood plasma samples were analyzed by NMR-based metabonomics, that is, high-resolution 1H NMR metabolic profiling combined with multivariate statistics. Green and black tea consumption resulted in similar increases in urinary excretion of hippuric acid and 1,3-dihydroxyphenyl-2-O-sulfate, both of which are end products of tea flavonoid degradation by colonic bacteria. Several unidentified aromatic metabolites were detected in urine specifically after green tea intake. Interestingly, green and black tea intake also had a different impact on endogenous metabolites in urine and plasma. Green tea intake caused a stronger increase in urinary excretion of several citric acid cycle intermediates, which suggests an effect of green tea flavanols on human oxidative energy metabolism and/or biosynthetic pathways.
Henning, Susanne M.; Wang, Piwen; Heber, David
The polyphenol compositions of green tea (GT) and black tea (BT) are very different due to post-harvest processing. GT contains higher concentrations of monomeric polyphenols, which affect numerous intracellular signaling pathways involved in prostate cancer (CaP) development. BT polymers, on the other hand, are poorly absorbed and are converted to phenolic acids by the colonic microflora. Therefore, after consumption of GT higher concentrations of polyphenols are found in the circulation while after BT consumption the phenolic acid levels in the circulation are higher. The majority of in vitro cell culture, in vivo animal, and clinical intervention studies examine the effects of extracts of GT or purified (-)-epigallocatechin-3-gallate (EGCG) on prostate carcinogenesis. These studies provide strong evidence supporting a chemopreventive effect of GT, but results from epidemiological studies of GT consumption are mixed. While the evidence for a chemopreventive effect of BT is much weaker than the body of evidence with regard to GT, there are several animal BT intervention studies demonstrating inhibition of CaP growth. This article will review in detail the available epidemiological and human clinical studies, as well as animal and basic mechanistic studies on GT and BT supporting a chemopreventive role in CaP. PMID:21538852
Melaleuca alternifolia essential oil enhances the non-specific immune system and prevents oxidative damage in Rhamdia quelen experimentally infected by Aeromonas hydrophila: Effects on cholinergic and purinergic systems in liver tissue.
Baldissera, Matheus D; Souza, Carine F; Júnior, Guerino B; de Vargas, Agueda C; Boligon, Aline A; de Campos, Marli M A; Stefani, Lenita M; Baldisserotto, Bernardo
The aim of this study was to evaluate the effects of M. alternifolia essential oil used to treat silver catfish (Rhamdia quelen) experimentally infected by Aeromonas hydrophila on oxidative stress variables, and for the first time, on hepatic enzymes of the cholinergic and adenosinergic systems. For that, fish were divided into six groups (A-F), each containing seven animals. Groups A, B and C were composed of uninfected animals, while animals in groups D, E and F were intramuscularly inoculated with A. hydrophila. Groups B and E received a prophylactic bath with M. alternifolia essential oil (50 μL/L, diluted in ethanol) for seven days, while groups C and F were exposed to ethanol. After the prophylactic baths, groups D, E and F were inoculated with 100 μL of A. hydrophila solution (2.1 × 10(9) colony-forming unit). Two days after inoculation, the animals were euthanized and liver samples were collected. Infected animals (the group D) showed increased TBARS and protein carbonylation levels, while CAT, AChE and ADA activities decreased compared to uninfected animals (the group A). The prophylactic treatment with M. alternifolia essential oil (the group E) prevented the alterations caused by A. hydrophila, but it did not change AChE activity. Thus, the prophylactic treatment prevents damage caused by lipids and proteins, as well as alterations of the adenosinergic system, demonstrating that the anti-inflammatory effect of TTO is mediated by the adenosinergic pathway. In addition, TTO prophylactic treatment might be considered an important approach to prevent the hepatic damage caused by A. hydrophila.
... Luncheon Registration Create Your Own Events Educational Events Tree Nut Allergies Tree nut allergy is one of ... with tree nuts during manufacturing and processing. Avoiding Tree Nuts The federal Food Allergen Labeling and Consumer ...
Zhang, Jianyang; Ma, Guicen; Chen, Liyan; Liu, Ting; Liu, Xin; Lu, Chengyin
Puerh tea, as the most representative Chinese dark tea, has attracted global interest in recent years. Profiling the levels of metal elements in Puerh tea is very important since its presence is related to human health. In this study, 41 elements in 98 Puerh tea samples from Yunnan province, China including Puerh raw tea and Puerh ripe tea were evaluated by microwave digestion combined with inductively coupled plasma mass spectrometry . The content of toxic elements, essential elements and rare earth elements of Puerh tea from different regions was discussed in detail. The concentrations of Ba, Cr, As, Pb, Bi, Fe, Zn, V, Mn, Be, Ag and Tl showed significant differences (p < 0.05) by ANOVA analysis. Principal component analysis and linear discriminant analysis were used to describe the relationship of Puerh tea from different regions. This study provided a comprehensive database for Puerh tea quality control and intake risk assessment.
Zhu, J N; Zhang, X L; Guo, H
Tea and wine are time-honored drinks in China. Along with coffee and cocoa, tea, as one of the non-alcoholic plant beverages, is prevailing the world. Tea and Chinese medicine has a very close relationship. Chinese herbs taken as tea forming the tea-like medicinal tea, can be taken frequently at anytime. The application of Chinese herbs taken as tea drinking begins from the Tang Dynasty, flourishes in the Song Dynasty and matures in the Qing Dynasty. The review of its history provides ample evidence of Chinese herbs taken as tea drinking in treating and preventing diseases, as well as providing the clues and references of developing new Chinese herbs taking as tea.
Venkateswara, Babu; Sirisha, K.; Chava, Vijay K.
Tea, the commonly consumed beverage, is gaining increased attention in promoting overall health. In specific, green tea is considered a healthful beverage due to the biological activity of its polyphenols namely catechins. Among the polyphenols Epigallo catechin 3 gallate and Epicatechin 3 Gallate are the most predominant catechins. The antioxidant, antimicrobial, anticollagenase, antimutagenic, and c hemopreventive properties of these catechins proved to be helpful in the treatment of chronic diseases like periodontal disease. Studies have demonstrated that the type of processing mainly effects the concentration of catechins. Several epidemiological studies have proved that green tea also has some general health benefitting properties like antihypertensive, reduction of cardiovascular risk, antibacterial, antiviral, and antifungal activity. The present review concentrates on the effects of green tea in periodontal and general health. PMID:21772716
Tree climbing offers a safe, inexpensive adventure sport that can be performed almost anywhere. Using standard procedures practiced in tree surgery or rock climbing, almost any tree can be climbed. Tree climbing provides challenge and adventure as well as a vigorous upper-body workout. Tree Climbers International classifies trees using a system…
Burda, Z; Erdmann, J; Petersson, B; Wattenberg, M
We discuss the scaling properties of free branched polymers. The scaling behavior of the model is classified by the Hausdorff dimensions for the internal geometry, d(L) and d(H), and for the external one, D(L) and D(H). The dimensions d(H) and D(H) characterize the behavior for long distances, while d(L) and D(L) for short distances. We show that the internal Hausdorff dimension is d(L)=2 for generic and scale-free trees, contrary to d(H), which is known to be equal to 2 for generic trees and to vary between 2 and infinity for scale-free trees. We show that the external Hausdorff dimension D(H) is directly related to the internal one as D(H)=alphad(H), where alpha is the stability index of the embedding weights for the nearest-vertex interactions. The index is alpha=2 for weights from the Gaussian domain of attraction and 0
Speisky, Hernán; Rocco, Claudia; Carrasco, Catalina; Lissi, Eduardo A; López-Alarcón, Camilo
Herbal tea consumption is deeply and widely rooted amongst South-American populations. In view of the involvement of oxygen- and nitrogen-reactive species in the ethiogenesis of several diseases, the antioxidant properties of some of the herbal teas most commonly consumed in the southern regions was assessed in vitro. Around one-third of the 13 examined herbs, displayed a substantially higher ability to scavenge ABTS(+.) radicals (TEAC assay), and to quench the pro-oxidant species, hypochlorite (HClO) and peroxynitrite (ONOO(-)). Amongst the tested herbs, teas prepared from Haplopappus baylahuen, Rosa moschata and Peumus boldus showed the highest TEAC and HClO-quenching activities. These herbs were around 5- to 7-fold more potent than the least active herbs. Based on the TEAC assay, 150 mL of tea prepared from H. baylahuen, R. moschata and P. boldus would be equivalent to around 200 mg of Trolox). Teas from H. baylahuen and P. boldus were also found to be particularly potent in quenching HClO. In the ONOO(-) assay, H. baylahuen and Buddleia globosa showed the highest activities. The results obtained suggest that the regular consumption of teas prepared from some of these herbs may be useful potentially to provide the organism with molecules capable of protecting the gastrointestinal tract against certain pathologically relevant oxidant species.
Ogura, R; Ikeda, N; Yuki, K; Morita, O; Saigo, K; Blackstock, C; Nishiyama, N; Kasamatsu, T
The beneficial effects of tea catechins are well documented. We evaluated the genotoxic potential of a green tea catechin preparation using established genotoxicity assays, including a bacterial reverse mutation assay (Ames test), a chromosomal aberration assay in cultured Chinese hamster lung cells (CHL/IU), a mouse lymphoma L5178Y/tk assay, and a bone marrow micronucleus (MN) assay in ICR CD mice and SD rats. No significant increases in the number of revertant colonies were observed in the Ames test, but positive responses were observed in two in vitro assays: the chromosomal aberration assay and mouse lymphoma L5178/tk assay. However, the in vivo study demonstrated no significant increase in micronucleated polychromatic erythrocytes (MNPCE) in the bone marrow of both ICR CD mice and SD rats administered a high dose of the green tea catechin preparation up to 2000mg/kg. Combined with favorable epidemiological information suggesting a chemopreventive effect of tea catechins on carcinogenesis, we conclude that green tea catechin presents no significant genotoxic concern under the anticipated conditions of use. These results are consistent with other genotoxicity studies of tea catechins, which show minimal, if any, genotoxic potential.
Yang, Xiaoping; Kong, Fanbin
The objective of this study was to determine whether green tea, black tea and oolong tea have inhibitory potential against α-glucosidase which may be used to control postprandial hyperglycemia in type 2 diabetes mellitus. Green tea polyphenols (TPs) strongly inhibited α-glucosidase activity by non-competitive inhibition with an IC50 value of 2.33 µg mL(-1) and the inhibitory effect was dependent on TP concentration and incubation order. Green tea, black tea and oolong tea also had dose-dependent inhibitory potential with IC50 values of 2.82, 2.25 and 1.38 µg mL(-1) (µg polyphenol mL(-1)), respectively. The study also showed that the content of unprecipitated TPs changed during enzymatic hydrolysis, leading to the change of the antioxidant activity. The change of the antioxidant activity of tea extracts revealed a similar trend to that of green TPs during enzymatic hydrolysis. Green TPs, green tea, black tea and oolong tea are excellent α-glucosidase inhibitors and their inhibitory potency is mainly attributed to TPs. These findings suggest that green tea, black tea and oolong tea can potentially be used to control postprandial hyperglycemia. © 2015 Society of Chemical Industry.
Xiang, Li-Ping; Wang, Ao; Ye, Jian-Hui; Zheng, Xin-Qiang; Polito, Curt Anthony; Lu, Jian-Liang; Li, Qing-Sheng; Liang, Yue-Rong
Tea leaf (Camellia sinensis) is rich in catechins, which endow tea with various health benefits. There are more than ten catechin compounds in tea, among which epigallocatechingallate (EGCG) is the most abundant. Epidemiological studies on the association between tea consumption and the risk of breast cancer were summarized, and the inhibitory effects of tea catechins on breast cancer, with EGCG as a representative compound, were reviewed in the present paper. The controversial results regarding the role of tea in breast cancer and areas for further study were discussed. PMID:27483305
Xiang, Li-Ping; Wang, Ao; Ye, Jian-Hui; Zheng, Xin-Qiang; Polito, Curt Anthony; Lu, Jian-Liang; Li, Qing-Sheng; Liang, Yue-Rong
Tea leaf (Camellia sinensis) is rich in catechins, which endow tea with various health benefits. There are more than ten catechin compounds in tea, among which epigallocatechingallate (EGCG) is the most abundant. Epidemiological studies on the association between tea consumption and the risk of breast cancer were summarized, and the inhibitory effects of tea catechins on breast cancer, with EGCG as a representative compound, were reviewed in the present paper. The controversial results regarding the role of tea in breast cancer and areas for further study were discussed.
Lin, Xiaorong; Chen, Zhongzheng; Zhang, Yuanyuan; Gao, Xiong; Luo, Wei; Li, Bin
In the 1980s, a novel tea species, Cocoa tea (Camellia ptilophylla Chang), was discovered in Southern China with surprisingly low caffeine content (0.2% by dry weight). Although its health promoting characteristics have been known for a while, a very limited amount of scientific research has been focused on Cocoa tea. Herein, a systematic study on Cocoa tea and its chemical components, interactions and bioactivities was performed. YD tea (Yunnan Daye tea, Camellia sinensis), a tea species with a high caffeine content (5.8% by dry weight), was used as a control. By UV-Vis spectrometry, High Performance Liquid Chromatography (HPLC), and Flame Atomic Absorption Spectrometry (FAAS) for chemical composition analysis, C-2 epimeric isomers of tea catechins and theobromine were found to be the major catechins and methylxanthine in Cocoa tea, respectively. More gallated catechins, methylxanthines, and proteins were detected in Cocoa tea compared with YD tea. Moreover, the tendency of major components in Cocoa tea for precipitation was significantly higher than that in YD tea. Catechins, methylxanthines, proteins, iron, calcium, and copper were presumed to be the origins of molecular interactions in Cocoa tea and YD tea. The interactions between catechins and methylxanthines were highly related to the galloyl moiety in catechins and methyl groups in methylxanthines. In vitro anti-inflammatory activity assays revealed that Cocoa tea was a more potent inhibitor of nitric oxide (NO) in lipopolysaccharide (LPS)-stimulated macrophage cells (RAW 264.7) than YD tea. This study constructs a solid phytochemical foundation for further research on the mechanisms of molecular interactions and the integrated functions of Cocoa tea.
Shi, Jiang; Wang, Li; Ma, Cheng-ying; Lv, Hai-peng; Chen, Zong-mao; Lin, Zhi
Methyl jasmonate (MeJA) was widely applied in promoting food quality. Aroma is one of the key indicators in judging the quality of tea. This study examined the effect of exogenous MeJA treatment on tea aroma. The aroma components in black tea prepared from MeJA-treated fresh tea leaves were extracted using headspace solid-phase microextraction (HS-SPME) and were analyzed using gas chromatography-mass spectrometry (GC-MS) and GC-olfactometry (GC-O). Forty-five volatile compounds were identified. The results revealed that the MeJA-treated black tea had higher levels of terpene alcohols and hexenyl esters than the untreated tea. Moreover, several newly components, including copaene, cubenol, and indole, were induced by the MeJA treatment. The activities of polyphenol oxidase and β-glucosidase in fresh tea leaves changed after the MeJA treatment. Quantitative real-time polymerase chain reaction (qRT-PCR) analysis indicated that the gene expression levels of polyphenol oxidase and β-primeverosidase were upregulated by two and three folds, respectively, by the MeJA treatment (P<0.01); however, the gene expression of β-glucosidase was downregulated to a half level. In general, the aroma quality of the MeJA-treated black tea was clearly improved. PMID:24711352
To help meet the needs of consumers, producers of dietary tea products, and researchers for information on health-promoting tea ingredients, we determined by HPLC seven catechins [(–)-epigallocatechin (EGC), (–)-catechin (C), (+)-epicatechin (EC), (–)-epigallocatechin 3-gallate (EGCG), (–)-gallocate...
Dekant, Wolfgang; Fujii, Kenkichi; Shibata, Eiichiro; Morita, Osamu; Shimotoyodome, Akira
The safety of green tea infusions and green tea extract (GTE)-based products is reviewed regarding catechins. Epigallocatechin 3-gallate (EGCG), the major catechin present in green tea, is suspected of being responsible for liver toxicity reported in humans consuming food supplements. Intake of EGCG with green tea infusions and GTE-based beverages is up to about 450mg EGCG/person/day in Europe and higher in Asia. Consumption of green tea is not associated with liver damage in humans, and green tea infusion and GTE-based beverages are considered safe in the range of historical uses. In animal studies, EGCG's potency for liver effects is highly dependent on conditions of administration. Use of NOAELs from bolus administration to derive a tolerable upper intake level applying the margin of safety concept results in acceptable EGCG-doses lower than those from one cup of green tea. NOAELs from toxicity studies applying EGCG with diet/split of the daily dose are a better point of departure for risk characterization. In clinical intervention studies, liver effects were not observed after intakes below 600mg EGCG/person/day. Thus, a tolerable upper intake level of 300mg EGCG/person/day is proposed for food supplements; this gives a twofold safety margin to clinical studies that did not report liver effects and a margin of safety of 100 to the NOAELs in animal studies with dietary administration of green tea catechins. Copyright © 2017 Elsevier B.V. All rights reserved.
Provides: (1) background information on trees, focusing on the parts of trees and how they differ from other plants; (2) eight activities; and (3) ready-to-copy pages dealing with tree identification and tree rings. Activities include objective(s), recommended age level(s), subject area(s), list of materials needed, and procedures. (JN)
Wu, Chia-Chang; Chu, Chun; Wang, Yei-Shung; Lur, Huu-Sheng
Carbofuran (2,3-dihydro-2,2-dimethyl-7-benzofuranol-N-methylcarbamate) and carbaryl (1-naphthyl-N-methylcarbamate) are insecticides widely used in tea plantations. The objective of the present study was to evaluate the dissipation of carbofuran and carbaryl during the growth periods of Oolong tea, processing and roasting. Analysis of the residual insecticides was carried out using high-pressure liquid chromatography with a post-column fluorescence detector. Results showed that in the tea field carbofuran dissipated faster then carbaryl. Manufacturing processes of Oolong tea further reduced the carbofuran and carbaryl contents. The persistence of carbofuran and carbaryl was decreased with increasing roasting temperature. From the results, we conclude that the presence of carbofuran and carbaryl in tea can be reduced by proper field management, manufacturing and roasting processes.
Chow, H-H. Sherry; Hakim, Iman A.
Green tea and its major polyphenols constituents, tea catechins, have been shown to have many health benefits including cancer prevention. Tea catechins and tea catechin metabolites/catabolites are bioavailable in the systemic circulation after oral intake of green tea or green tea catechins. The metabolites/catabolites identified in humans include glucuronide/sulfate conjugates, methylated tea catechin conjugates, and microflora-mediated ring fission products and phenolic acid catabolites. Plasma levels of unchanged tea catechins in humans are mostly in the sub-μM or nM concentration range, which is much lower than the effective concentrations determined in most in vitro studies. However, some of the catechin metabolites/catabolites are present in the systemic circulation at levels much higher than those of the parent catechins. The contribution of catechin derived metabolites/catabolites to the biological effects associated with green tea is yet to be defined. A limited number of chemoprevention trials of green tea or green tea catechins have been conducted to date and have observed potential preventive activity for oral, prostate, and colorectal cancer. Emerging data from multiple ongoing intervention trials will further contribute to defining the cancer preventive activity of green tea or green tea catechins. PMID:21624470
Takahashi, Atsushi; Kishi, Yasuhiro; Ogawa, Hideyuki; Nakajima, Kenta
In order to clarify the change in the leaves of agricultural chemicals during the green tea manufacturing process, we analyzed chlorfenapyr in tea leaves obtained at each processing stage by using an immunoassay. Chlorfenapyr is a novel broad-spectrum insecticide-miticide registered in many countries for the control of various insects and mite pests. Chlorfenapyr is stable and persistent in the environment. Furthermore, it is widely applied for tea cultivation in Japan. Therefore, we selected chlorfenapyr for analysis in this study. In the unrefined tea (Aracha) manufacturing process, the highest level of chlorfenapyr was 16.5 ppm, which was obtained in tea powder separated from leaves at the secondary drying stage. However, the level at the other processing stages in tea leaves was approximately 9 ppm, and no significant difference in the chlorfenapyr level was detected between the processing stages. After Aracha processing, tea leaves are classified on the basis of their size, shape and color; this is the refined tea (Shiagecha) manufacturing process. After this process, although a high level of chlorfenapyr was detected in bud tea (8.1 ppm) and honcha (on-grade tea; 6.2 ppm), the level in the other classified teas was approximately 4.0 ppm. Thus, this paper shows the difference in the chlorfenapyr level in tea leaves obtained at each processing stage. This indicated that there are significant differences in the agricultural chemical levels between the green tea processing stages.
E.G. McPherson; F. Ferrini
We know that âtrees are good,â and most people believe this to be true. But if this is so, why are so many trees neglected, and so many tree wells empty? An individualâs attitude toward trees may result from their firsthand encounters with specific trees. Understanding how attitudes about trees are shaped, particularly aversion to trees, is critical to the business of...
Butt, Masood Sadiq; Sultan, Muhammad Tauseef
The current practice of introducing phytochemicals to support the immune system or fight against diseases is based on centuries old traditions. Nutritional support is a recent advancement in the domain of diet-based therapies; green tea and its constituents are one of the important components of these strategies to prevent and cure various malignancies. The anti-carcinogenic and anti-mutagenic activities of green tea were highlighted some years ago suggesting that it could reduce the prevalence of cancer and even provide protection. The pharmacological actions of green tea are mainly attributed to polyphenols that includes epigallocatechin-3-gallate (EGCG), epicatechin, epicatechin-3-gallate, epigallocatechin. Green tea and its components effectively mitigate cellular damage arising due to oxidative stress. Green tea is supposed to enhance humoral and cell-mediated immunity, decreasing the risk of certain cancers, and may have certain advantage in treating inflammatory disorders. Much of the cancer chemopreventive properties of green tea are mediated by EGCG that induces apoptosis and promotes cell growth arrest, by altering the expression of cell cycle regulatory proteins, activating killer caspases, and suppressing nuclear factor kappa-B activation. Besides, it regulates and promotes IL-23 dependent DNA repair and stimulates cytotoxic T cells activities in a tumor microenvironment. It also blocks carcinogenesis by modulating the signal transduction pathways involved in cell proliferation, transformation, inflammation and metastasis. The review is intended to highlight the chemistry of green tea, its antioxidant potential, its immunopotentiating properties and mode of action against various cancer cell lines that showed its potential as a chemopreventive agent against colon, skin, lung, prostate, and breast cancer.
Zakir, Muhammad; Sultan, Khush Bakht; Khan, Haroon; Ihsaanullah; Khan, Murad Ali; Fazal, Hina; Rauf, Abdur
In this antimicrobial study, various extracts of Green and Black tea (Camellia sinensis) and Lemon grass (Cymbopogon citrates) were evaluated for antimicrobial activities against six bacterial strains including both human pathogenic bacteria (Escherichia coli, Pseudomonas aeuroginosa, Staphylococcus aureus and Salmonella typhi) and plant pathogenic bacteria (Erwinia carotovora, Agro bacterium tumifaciens) and one fungal strain Candida albicans by disc diffusion susceptibility method. Of human pathogens, P. aeruginosa was most susceptible to all three different tea varieties; though rest of the strains also demonstrated prominent sensitivity. In comparison, black tea extracts were less activities than green tea and lemon grass. However, all the three tea varieties illustrated profound activity against plant pathogenic bacteria. Similarly, when extracts of tea were tested against C. albicans, green tea and lemon grass exhibited significant activity while black tea was mostly inactive.
Banerjee, Satarupa; Chatterjee, Jyotirmoy
Tea is a popular daily beverage worldwide. Modulation and modifications of its basic components like catechins, alkaloids, proteins and carbohydrate during fermentation or extraction process changes organoleptic, gustatory and medicinal properties of tea. Through these processes increase or decrease in yield of desired components are evident. Considering the varied impacts of parameters in tea production, storage and processes that affect the yield, extraction of tea biomolecules at optimized condition is thought to be challenging. Implementation of technological advancements in green chemistry approaches can minimize the deviation retaining maximum qualitative properties in environment friendly way. Existed extraction processes with optimization parameters of tea have been discussed in this paper including its prospects and limitations. This exhaustive review of various extraction parameters, decaffeination process of tea and large scale cost effective isolation of tea components with aid of modern technology can assist people to choose extraction condition of tea according to necessity.
Grando, T H; de Sá, M F; Baldissera, M D; Oliveira, C B; de Souza, M E; Raffin, R P; Santos, R C V; Domingues, R; Minho, A P; Leal, M L R; Monteiro, S G
Haemonchus contortus is one of the major gastrointestinal nematodes responsible for significant economic and production losses of sheep. Diseases caused by this species lack effective anthelmintic products, and the search for new compounds to replace synthetic anthelmintics has been extensive. The present investigation assesses the in vitro activity of the essential oil of melaleuca (Melaleuca alternifolia), both free (TTO) and nanostructured (nanoTTO), and terpinen-4-ol (terp-4-ol) on eggs and larvae of H. contortus. Tests of egg hatching (EHT) and inhibition of larval migration (LMIT) were used to assess the in vitro efficacy of TTO, nanoTTO and terp-4-ol. Using EHT, at a concentration of 3.5 mg/ml, 100% inhibition occurred using TTO and terp-4-ol, with LC50 values of 0.43 and 0.63 mg/ml, and LC90 values of 1.75 mg/ml and 3.12 mg/ml, respectively. NanoTTO had lower activity, with 82.6% inhibition at the same concentration. Using LMIT, TTO and nanoTTO had a similar activity with 88.0% and 84.8% inhibition, respectively, at a concentration of 56 mg/ml. Terp-4-ol had a greater effect on larvae, with 85.7% inhibition at a concentration of 56 mg/ml and 82.4% at 3.5 mg/ml, demonstrating high activity at the lowest concentration tested. Therefore, the results indicate that all substances tested showed ovicidal and larvicidal activity against H. contortus. TTO, terp-4-ol and, mainly, nanoTTO may be targeted in in vivo studies, besides being a promising line of research into the control and treatment of veterinary important helminths.
Lee, Andy H; Liang, Wenbin; Hirayama, Fumi; Binns, Colin W
Green tea is a popular beverage and its health benefits are well known. However, inconsistent results have been reported in observational studies concerning the association between green tea consumption and the lung cancer risk. In this commentary, several methodological issues underlying the measurement of tea exposure are highlighted. The recommendations should be useful for designing and planning prospective cohort studies to ascertain the protective effect of green tea against lung cancer.
Green tea consumption has been associated with a decrease in the risk of some cancer types in humans. Epidemiological studies, though inconclusive...suggest that drinking green tea may lower the risk of prostate cancer (Cap) in humans. Here we report that polyphenolic mixture obtained from green tea 0.1...GTP (w/v) in drinking water at a human achievable dose (equivalent to six cups of green tea per day) significantly inhibits prostate cancer
Epidemiological studies, though inconclusive suggest that drinking green tea may lower the risk of prostate cancer (CaP) in humans. Here we report...that polyphenols present in green tea especially its major constituent (-) epigallocatechin- 3-gallate (EGCG) possesses both cancer preventive and...polyphenolic fraction isolated from green tea at a human achievable dose (equivalent to six cups of green tea per day) significantly inhibited CaP
Cabrera, Carmen; Giménez, Rafael; López, M Carmen
Levels of essential elements with antioxidant activity, as well as catechins, gallic acid, and caffeine levels, in a total of 45 samples of different teas commercialized in Spain have been evaluated. Chromium, manganese, selenium, and zinc were determined in the samples mineralized with HNO(3) and V(2)O(5), using ETAAS as the analytical technique. The reliability of the procedure was checked by analysis of a certified reference material. Large variations in the trace element composition of teas were observed. The levels ranged from 50.6 to 371.4 ng/g for Cr, from 76.1 to 987.6 microg/g for Mn, from 48.5 to 114.6 ng/g for Se, and from 56.3 to 78.6 ng/g for Zn. The four major catechins [(-)-epigallocatechin gallate (EGCG), (-)-epigallocatechin (EGC), (-)-epicatechin gallate (ECG), and (-)-epicatechin (EC)], gallic acid (GA), and caffeine were simultaneously determined by a simple and fast HPLC method using a photodiode array detector. In all analyzed samples, EGCG ranged from 1.4 to 103.5 mg/g, EGC from 3.9 to 45.3 mg/g, ECG from 0.2 to 45.6 mg/g, and EC ranged from 0.6 to 21.2 mg/g. These results indicated that green tea has a higher content of catechins than both oolong and fermented teas (red and black teas); the fermentation process during tea manufacturing reduces the levels of catechins significantly. Gallic acid content ranged from 0.039 to 6.7 mg/g; the fermentation process also elevated remarkably gallic acid levels in black teas (mean level of 3.9 +/- 1.5 mg/g). The amount of caffeine in the analyzed samples ranged from 7.5 to 86.6 mg/g, and the lower values were detected in green and oolong teas. This study will be useful for the appraisal of trace elements and antioxidant components in various teas, and it will also be of interest for people who like drinking this beverage.
Moitra, S; Thapa, P; Das, P; Das, J; Debnath, S; Singh, Mahipal; Datta, A; Sen, S; Moitra, S
Indian tea industry workers are exposed to various exposures at their workplace. To investigate the respiratory health of Indian tea industry workers. We administered a respiratory questionnaire to and measured lung function in workers of 34 tea gardens and 46 tea factories. We used correlation matrices to test the association between their respiratory symptoms and lung functions. The garden workers complained of shortness of breath 3 times higher than the factory workers. However, nasal allergy was more predominant among the factory workers compared to garden workers (69.6% vs 41.2%, p=0.02). The factory workers had higher total (median 107.3% vs 92.9%, p=0.05, as measured by R at 5 Hz) and peripheral airway resistance (143.8% vs 61.1%, p=0.005, as measured by R at 5-20 Hz) than the garden workers. Respiratory symptoms were inversely associated with airway obstruction as measured by the ratio between forced expiratory volume in 1 second (FEV1) and forced vital capacity (FVC) and positively correlated with increased overall airway reactance among the workers. Respiratory symptoms and increased allergen susceptibility of Indian tea industry workers due to occupational exposures warrant routine systematic surveillance of their workplace air quality and health monitoring.
Webb, Richard; Forbatha, Ann
Strategies for using trees in classroom instruction are provided. Includes: (1) activities (such as tree identification, mapping, measuring tree height/width); (2) list of asthetic, architectural, engineering, climate, and wildlife functions of trees; (3) tree discussion questions; and (4) references. (JN)
David J. Nowak; Jeffrey T. Walton; James Baldwin; Jerry. Bond
Information on street trees is critical for management of this important resource. Sampling of street tree populations provides an efficient means to obtain street tree population information. Long-term repeat measures of street tree samples supply additional information on street tree changes and can be used to report damages from catastrophic events. Analyses of...
Joe R. McBride; David J. Nowak
A survey of published reports on urban park tree inventories in the United States and the United Kingdom reveal two types of inventories: (1) Tree Location Inventories and (2) Generalized Information Inventories. Tree location inventories permit managers to relocate specific park trees, along with providing individual tree characteristics and condition data. In...
Katie Himanga; Douglas Jones; Jean Miller; Janette Monear; Gail Steinman; Katherine Widin
Tree Trust has been helping people plant trees in their communities since 1976. Our goal is to educate people about the importance of trees in their community and guide them through the process of successful tree-planting projects. Franklin Delano Roosevelt once said ?to exist as a nation, to prosper as a state, and to live as a people, we must have trees?....
In contrast to the consistent results of an inhibitory effect of green tea extracts and tea polyphenols on the development and growth of carcinogen-induced tumors in experimental animal models, results from human studies are mixed. Both observational and intervention studies have provided evidence in support of a protective role of green tea intake in the development of oral–digestive tract cancer or an inhibitory role of oral supplementation of green tea extract on a precancerous lesion of oral cavity. Evidence in support of green tea intake against the development of liver cancer risk is limited and inconsistent. An inverse association between green tea intake and lung cancer risk has been observed among never smokers but not among smokers. Although observational studies do not support a beneficial role of tea intake against the development of prostate cancer, several phase 2 clinical trials have shown an inhibitory effect of green tea extract against the progression of prostate premalignant lesions to malignant tumors. Prospective epidemiologic studies so far have not provided evidence for a protective effect of green tea consumption on breast cancer development. Current data neither confirm nor refute a definitive cancer-preventive role of green tea intake. Large randomized intervention trials on the efficacy of green tea polyphenols or extracts are required before a recommendation for green tea consumption for cancer prevention should be made. PMID:24172305
Komatsu, Tatsushi; Nakamori, Masayo; Komatsu, Keiko; Hosoda, Kazuaki; Okamura, Mariko; Toyama, Kenji; Ishikura, Yoshiyuki; Sakai, Tohru; Kunii, Daisuke; Yamamoto, Shigeru
Oolong tea is a traditional Chinese tea that has long been believed to be beneficial to health such as decreasing body fat. We were interested in this assertion and tried to evaluate the effect of oolong tea on energy expenditure (EE) in comparison with green tea. The subjects were eleven healthy Japanese females (age 20+/-1 y; body mass index (BMI) 21.2+/-2.5 kg/m2) who each consumed of three treatments in a crossover design: 1) water, 2) oolong tea, 3) green tea. Resting energy expenditure (REE) and EE after the consumption of the test beverage for 120 min were measured using an indirect calorimeter. The cumulative increases of EE for 120 min were significantly increased 10% and 4% after the consumption of oolong tea and green tea, respectively. EE at 60 and 90 min were significantly higher after the consumption of oolong tea than that of water (P<0.05). In comparison with green tea, oolong tea contained approximately half the caffeine and epigallocatechin galate, while polymerized polyphenols were double. These results suggest that oolong tea increases EE by its polymerized polyphenols.
In contrast to the consistent results of an inhibitory effect of green tea extracts and tea polyphenols on the development and growth of carcinogen-induced tumors in experimental animal models, results from human studies are mixed. Both observational and intervention studies have provided evidence in support of a protective role of green tea intake in the development of oral-digestive tract cancer or an inhibitory role of oral supplementation of green tea extract on a precancerous lesion of oral cavity. Evidence in support of green tea intake against the development of liver cancer risk is limited and inconsistent. An inverse association between green tea intake and lung cancer risk has been observed among never smokers but not among smokers. Although observational studies do not support a beneficial role of tea intake against the development of prostate cancer, several phase 2 clinical trials have shown an inhibitory effect of green tea extract against the progression of prostate premalignant lesions to malignant tumors. Prospective epidemiologic studies so far have not provided evidence for a protective effect of green tea consumption on breast cancer development. Current data neither confirm nor refute a definitive cancer-preventive role of green tea intake. Large randomized intervention trials on the efficacy of green tea polyphenols or extracts are required before a recommendation for green tea consumption for cancer prevention should be made.
Sheibani, Ershad; Duncan, Susan E; Kuhn, David D; Dietrich, Andrea M; Newkirk, Jordan J; O'Keefe, Sean F
Panning is a processing step used in manufacturing of some varieties of oolong tea. There is limited information available on effects of panning on oolong tea flavors. The goal of this study was to determine effects of panning on flavor volatile compositions of oolong using Gas Chromatography-Mass Spectrometry (GC-MS) and Gas Chromatography-Olfactometry (GC-O). SDE and SPME techniques were applied for extraction of volatiles in panned and unpanned teas. A total of 190 volatiles were identified from SDE and SPME extractions using GC-MS and GC-O. There were no significant differences (P > 0.05) in aldehyde or terpene contents of unpanned and panned tea. However, alcohols, ketones, acids and esters contents were significantly reduced by panning. Among 12 major volatiles previously used for identification and quality assessment of oolong tea, trans nerolidol, 2- hexenal, benzaldehyde, indole, gernaiol, and benzenacetaldehyde contents were significantly decreased (P < 0.05) by panning. Panning increased (P < 0.05) contents of linalool oxide, cis jasmone, and methyl salicylate. The GC-O study also showed an increase of aroma active compounds with sweet descriptions and decrease of aroma active compounds with fruity and smoky descriptions after panning. Panning significantly changes the volatile compositions of the tea and created new aroma active compounds. Results from this study can be used in quality assessment of panned oolong tea.
Samant, Shilpa. S.; Wilkes, Katherine; Odek, Zephania; Seo, Han-Seok
The food and beverage industry has been increasingly replacing sugar with non-nutritive sweeteners in their sweetened products to control or reduce total calories. Research comparing the effect of nutritive and non-nutritive sweeteners on emotional state of participants exposed to acute stressors is still limited. This study aimed to determine the effect of drinking tea sweetened with either a nutritive sweetener (sugar) or a non-nutritive sweetener (sucralose or stevia) on emotional state, in terms of calmness and pleasantness, of participants exposed to an acute stressor. Effects of acute stress on sweetness intensity and overall liking of tea beverages were also determined. Results showed that the possibility of tea-induced calmness, calculated as the difference between calmness ratings after and before drinking a tea sample, was established on stress session in the sugar-sweetened tea. Overall liking, but not the sweetness intensity, of the sugar-sweetened tea was affected by acute stress. In conclusion, this study provides empirical evidence that the consumption of tea sweetened with nutritive sweetener, but not with non-nutritive sweetener, has calming effect on consumers with acute stress, suggesting that this effect may not be due to the sweet taste of sugar, but due to the caloric nature of the sweetener. PMID:27848976
Shimshoni, Jakob Avi; Duebecke, Arne; Mulder, Patrick P J; Cuneah, Olga; Barel, Shimon
Dehydro pyrrolizidine alkaloids (dehydro PAs) are carcinogenic phytotoxins prevalent in the Boraginaceae, Asteraceae and Fabaceae families. Dehydro PAs enter the food and feed chain by co-harvesting of crops intended for human and animal consumption as well as by carry-over into animal-based products such as milk, eggs and honey. Recently the occurrence of dehydro PAs in teas and herbal teas has gained increasing attention from the EU, due to the high levels of dehydro PAs found in commercially available teas and herbal teas in Germany and Switzerland. Furthermore, several tropane alkaloids (TAs, e.g. scopolamine and hyoscyamine) intoxications due to the consumption of contaminated herbal teas were reported in the literature. The aim of the present study was to determine the dehydro PAs and TAs levels in 70 pre-packed teabags of herbal and non-herbal tea types sold in supermarkets in Israel. Chamomile, peppermint and rooibos teas contained high dehydro PAs levels in almost all samples analysed. Lower amounts were detected in black and green teas, while no dehydro PAs were found in fennel and melissa herbal teas. Total dehydro PAs concentrations in chamomile, peppermint and rooibos teas ranged from 20 to 1729 μg/kg. Except for black tea containing only mono-ester retrorsine-type dehydro PAs, all other teas and herbal teas showed mixed patterns of dehydro PA ester types, indicating a contamination by various weed species during harvesting and/or production. The TA levels per teabag were below the recommended acute reference dose; however, the positive findings of TAs in all peppermint tea samples warrant a more extensive survey. The partially high levels of dehydro PAs found in teas and herbal teas present an urgent warning letter to the regulatory authorities to perform routine quality control analysis and implement maximum residual levels for dehydro PAs.
Hou, C W; Jeng, K C; Chen, Y S
Pu-erh tea is known as a fermented tea and longer storage enhances its flavor and taste. Recently, Aspergillus, Blastobotrys, and Streptomyces are found to play important roles in nutritional enhancement of Pu-erh tea by fermentation. Since water and temperature affect the microbial growth, we therefore explored the factors that might enhance the Pu-erh tea fermentation. The results showed that the addition of fresh tea-leaf extract (TLE) enhanced the withered tea fermentation (at 37 degrees C, 80 to 85% RH) as compared with the water only. Contents of statin, GABA, gallic acid, DPPH scavenging and polyphenol oxidase (PPO) activities were increased, whereas polyphenols and caffeine were decreased over 6 mo. TLE dose-dependently enhanced some of the qualities (that is, statin, PPO) of Pu-erh tea significantly as compared with the water only. The effect was related to the increase population of A. niger and A. carbonarius at 6 mo (from 7.6 +/- 1.2 x 10(1) and 3.2 +/- 1.3 x 10(1) to 3.1 +/- 1.2 x 10(6) and 2.4 +/- 1.1 x 10(5) colony forming units [CFU]/g, respectively). After drying process (90 degrees C, 30 min), the total microbial count from these samples returned to background level (3 +/- 0.5 x 10(2) CFU/g). None of ochratoxin and fumonisin, toxins from Aspergillus, was detected in the final products. The flavor and taste were also enhanced by treatment with TLE. The inoculation with S. cinereus Y11 with 2% TLE further enhanced these functional contents (about 2-fold increase of statin level) in the experimental Pu-erh tea. Therefore, this result may add a new process for Pu-erh tea manufacture.
Ji, Peng-Zhang; Jiang, Hui-Bing; Huang, Xing-Qi; Zhang, Jun; Liang, Min-Zhi; Wang, Ping-Sheng
This study was conducted to evaluate the genetic diversity within and among the plants of four ancient tea gardens and two tableland tea gardens form Yunnan Province, China by AFLP technique. The percentage of polymorphic loci (P) of the plants from six tea gardens was 92.31%. The genetic diversity within the six gardens demonstrated by Nei cents genetic diversity (He) was estimated to be 0.1366, while Shannon indices (Ho) were 0.2323. The percentage of polymorphic loci of the four ancient tea populations was 45.55% on average, with a range of 36.44% (Mengsong) to 59.11% (Mengla). But the percentages of polymorphic loci of the plants from two tableland gardens were 13.77% (Yunkang 10) and 24.2% (Menghai Daye), respectively. There was a great genetic difference between ancient tea gardens and tableland tea gardens. The genetic diversity among the plants of the ancient tea garden was higher than those of the sexual tableland tea garden and the clone tableland tea garden based on P valve. The four ancient tea gardens and two tableland gardens could be differentiated with AFLP markers. The results show that AFLP marker is an effective tool in the discrimination of tea germplasm, as well as sundried green tea.
Sattath, Shmuel; Tversky, Amos
Tree representations of similarity data are investigated. Hierarchical clustering is critically examined, and a more general procedure, called the additive tree, is presented. The additive tree representation is then compared to multidimensional scaling. (Author/JKS)
trees (similar to the role played by the finite- state acceptor FSA for strings). We describe the version (equivalent to TSG ( Schabes , 1990)) where...strictly contained in tree sets of tree adjoining gram- mars (Joshi and Schabes , 1997). 4 Extended-LHS Tree Transducers (xR) Section 1 informally described...changes without modifying the training procedure, as long as we stick to tree automata. 10 Related Work Tree substitution grammars or TSG ( Schabes , 1990
Disler, P B; Lynch, S R; Charlton, R W; Torrance, J D; Bothwell, T H; Walker, R B; Mayet, F
The effect of tea on iron absorption was studied in human volunteers. Absorption from solutions of FeCl3 and FeSO4, bread, a meal of rice with potato and onion soup, and uncooked haemoglobin was inhibited whether ascorbic acid was present or not. No inhibition was noted if the haemoglobin was cooked. The effect on the absorption of non-haem iron was ascribed to the formation of insoluble iron tannate complexes. Drinking tannin-containing beverages such as tea with meals may contribute to the pathogenesis of iron deficiency if the diet consists largely of vegetable foodstuffs. PMID:1168162
Pouretedal, Zohreh; Mazaheri, Mansooreh
Aflatoxins (AFs) are highly toxic, and carcinogenic secondary fungal metabolites and have been detected in various food commodities. In this regard, 40 black tea samples including domestic and imported black tea were analysed for aflatoxin contamination by high-performance liquid chromatography using a post-column derivatisation procedure (Kobra cell) with fluorescence detection. Samples were randomly collected in 2010 from Tehran markets. The results revealed that 30 among 40 samples were contaminated with aflatoxins (27.5% of the total). Mean AFB1 content was 10.0 ng/g and mean of aflatoxin total was 12.07 ng/g for the 11 contaminated samples.
Uegaki, R; Eun, H; Kuwahara, M; Ishii, Y; Kobara, Y; Ueji, M; Nakamura, K; Narita, I
Dioxin concentrations and homologue profiles were examined in plucked new shoots, crude tea and its hot water extracts, soils and atmosphere in tea orchards. The rate of dry provisions in crude tea has increased 4 times as that of the plucked new shoots. However, dioxin concentrations except O8CDD in crude tea have increased only 2 to 3 times as those of the plucked new shoots. O8CDD concentration increased remarkably during processing. Little dioxins were detected in hot water extracts of crude tea leaves.
Shiah, Yung-Jong; Radin, Dean
This study explored whether drinking tea "treated" with good intentions would enhance mood more than drinking ordinary tea, under double-blind, randomized conditions. Each evening, for seven days in a row, volunteers recorded their mood using the Profile of Mood States (POMS) questionnaire. On days three, four, and five of the test, each participant drank 600 mL of oolong tea in the morning and again in the afternoon. One randomly assigned group blindly received tea that had been intentionally treated by three Buddhist monks; the other group blindly received untreated tea from the same source. On the last day of the test, each person indicated what type of tea he/she believed he/she had been drinking. Stratified, random sampling was used to assign 189 adults into two groups matched by age, gender, the psychological trait of neuroticism, and the amount of tea consumed on average per day. All participants were Taiwanese and lived in Kaohsiung, Taiwan, and the test was conducted over the course of one week to reduce mood fluctuations due to changes in local weather and other common influences. Those who drank treated tea showed a greater increase in mood than those who drank untreated tea (Cohen's d = 0.65, P = .02, two-tailed). Change in mood in those who believed that they were drinking treated tea was much better than those who did not believe (Cohen's d = 1.45, P = .00002, two-tailed). Tea treated with good intentions improved mood more than ordinary tea derived from the same source. Belief that one was drinking treated tea produced a large improvement in mood, but only if one was actually drinking the treated tea, indicating that belief and intentional enhancement interact. This also suggests that the esthetic and intentional qualities associated with the traditional tea ceremony may have subtle influences that extend beyond the ritual itself. © 2013 Elsevier Inc. All rights reserved.
Cabrera, Carmen; Artacho, Reyes; Giménez, Rafael
Tea is the most consumed drink in the world after water. Green tea is a 'non-fermented' tea, and contains more catechins, than black tea or oolong tea. Catechins are in vitro and in vivo strong antioxidants. In addition, its content of certain minerals and vitamins increases the antioxidant potential of this type of tea. Since ancient times, green tea has been considered by the traditional Chinese medicine as a healthful beverage. Recent human studies suggest that green tea may contribute to a reduction in the risk of cardiovascular disease and some forms of cancer, as well as to the promotion of oral health and other physiological functions such as anti-hypertensive effect, body weight control, antibacterial and antivirasic activity, solar ultraviolet protection, bone mineral density increase, anti-fibrotic properties, and neuroprotective power. Increasing interest in its health benefits has led to the inclusion of green tea in the group of beverages with functional properties. However, although all the evidence from research on green tea is very promising, future studies are necessary to fully understand its contributions to human health, and advise its regular consumption in Western diets, in which green tea consumption is nowadays limited and sporadic.
Nash, L A; Ward, W E
Globally, tea is the second most consumed beverage after water. Habitual tea intake has been associated with higher bone mineral density, particularly in postmenopausal women. This association may be due to its polyphenols and resulting protective antioxidant effects. While in vivo studies have shown improved bone outcomes with a consumption of individual purified tea polyphenols, it is unclear if a particular tea - due to its different profiles of polyphenols - is more beneficial than others. Therefore, we compared three different types of commercially available teas on osteoblasts: green, black and rooibos tea. Tea was normalized to 1 or 10 μg per mL gallic acid equivalents to assess differences in outcomes based on tea profiles rather than the quantity of polyphenol naturally present. The lower level of polyphenols (1 μg per mL gallic acid equivalents) - regardless of tea type and thus polyphenol profile - resulted in greater mineral content as well as cellular and alkaline phosphatase activity in Saos2 cells. Moreover, this was associated with higher markers of differentiation (osteopontin, sclerostin) and reduced cellular toxicity and pro-inflammatory markers (IL6, TNFα). Green, black and rooibos tea improved osteoblast activity at the low level and support epidemiological evidence suggesting tea consumption may benefit bone heath.
Kohlmeier, L; Weterings, K G; Steck, S; Kok, F J
Animal and in vitro studies provide evidence of an anticarcinogenic potential of active ingredients in teas. This review encompasses epidemiologic studies of stomach, colon, and lung cancer as well as the evidence of a relationship between tea drinking and cancer at large in humans. Cohort studies do not suggest a protective role for tea drinking in the total risk of cancer. Site-specific studies reveal a more complex picture. The epidemiologic studies on tea drinking and stomach cancer do not justify claims of a cancer-protective effect. A protective effect of green tea on the development of colon cancer is suggested. The evidence regarding black tea is less clear, with some indication of a risk of colon or rectal cancer associated with regular use of black tea. The studies on tea and lung cancer also suggest an increased risk with increased tea consumption. The range and crude categorization of tea consumption, choice of control groups, and inadequate control for confounding might have obscured possible relationships. From the limited studies that suggest a favorable effect from tea, it is likely that benefits are restricted to high intakes in high-risk populations.
Bertram, Barbara; Bartsch, H
Different processing of the leaves of the tea plant Camellia sinensis yields green or black tea, the subject of numerous investigations on the preventive effects on chronic degenerative diseases. The tea polyphenols, in particular (-)-epigallocatechin gallate (EGCG) were found to account for most of the protective effects. Since the concentration of EGCG is 5 times higher in green than in black tea, it is assumed that green tea possesses a greater preventive potential. Protection against cancer and cardiovascular diseases are the most important biomedical effects. In experimental models the preventive activity of tea is well documented for tumors at many organ sites. In humans, tea was reported to be protective against tumors of the lung, the gastrointestinal tract and the liver. Tea polyphenols, especially EGCG, were shown to exert cancer-protective activity by the following mechanisms: they inhibit the metabolic activation of carcinogens and induce at the same time detoxifying enzymes. They inhibit signaling pathways controlling cell proliferation and tumor growth such as protein kinase C and the release of tumor necrose factor-alpha from cells. Tea polyphenols reactivate processes which are impaired in tumor cells, such as the programmed cell death and the tumorsuppressor gene p53. Finally, tea polyphenols can also block angiogenesis leading to a starvation of the tumor. By inactivation of proteolytic enzymes they inhibit the development of metastases. This short review summarizes relevant recent findings on the protective effects of green tea constituents.
Researches on tea have been developed for decades, which prove that tea, especially green tea, has multiple functional components. With the rapid development of beverage industry, the resultant large amounts of tea grounds attract great attention. However, unreasonable utilization of tea grounds would lead to great waste and environmental pollution, especially in summer. In view of the high nutritive value and multiple functional components, tea grounds could be used as feedstuff. By now, researches of tea grounds as feedstuff are mainly on ruminant, as the utilization on other animals is limited to lower level due to high fiber content. Therefore, the following review will begin with a brief introduction of tea grounds and the possible utilization of tea grounds as feedstuff, and then elaborate on the application of ensiling and total mixed ration on ruminant. Apart from the fermentation quality, nutritive value is also provided to assess feasibilities of using tea grounds as feedstuff resources. Finally, a summary on the utilization situation and future direction of using tea grounds as feedstuff is provided in this review. PMID:24369099
Khurshid, Zohaib; Zafar, Muhammad S; Zohaib, Sana; Najeeb, Shariq; Naseem, Mustafa
Green tea is a widely consumed beverage worldwide. Numerous studies have suggested about the beneficial effects of green tea on oral conditions such as dental caries, periodontal diseases and halitosis. However, to date there have not been many review articles published that focus on beneficial effects of green tea on oral disease. The aim of this publication is to summarize the research conducted on the effects of green tea on oral cavity. Green tea might help reduce the bacterial activity in the oral cavity that in turn, can reduce the aforementioned oral afflictions. Furthermore, the antioxidant effect of the tea may reduce the chances of oral cancer. However, more clinical data is required to ascertain the possible benefits of green tea consumption on oral health.
Khurshid, Zohaib; Zafar, Muhammad S.; Zohaib, Sana; Najeeb, Shariq; Naseem, Mustafa
Green tea is a widely consumed beverage worldwide. Numerous studies have suggested about the beneficial effects of green tea on oral conditions such as dental caries, periodontal diseases and halitosis. However, to date there have not been many review articles published that focus on beneficial effects of green tea on oral disease. The aim of this publication is to summarize the research conducted on the effects of green tea on oral cavity. Green tea might help reduce the bacterial activity in the oral cavity that in turn, can reduce the aforementioned oral afflictions. Furthermore, the antioxidant effect of the tea may reduce the chances of oral cancer. However, more clinical data is required to ascertain the possible benefits of green tea consumption on oral health. PMID:27386001
Zhang, Haihua; Sun, Binghua; Zhang, Shikang; Zhu, Yuejin; Tian, Yaoqi
The effect of four industrial tea derivatives (tea polyphenols [TPS], tea water-soluble extracts [TSE], tea polysaccharides [TSS], and green tea powder [GTP]), on the retrogradation of wheat starch was investigated using texture profile analysis (TPA), differential scanning calorimetry (DSC), rapid viscosity analysis (RVA), and the α-amylase-iodine method. The addition of the four tea derivatives resulted in decreased hardness and increased cohesiveness of the starch gel as shown by the TPA test. The DSC data demonstrated an increase in the enthalpy change of starch gelatinization and a decrease in the enthalpy change of starch recrystallite dissociation. The RVA results indicated that the peak viscosity, representing the intermolecular forces of wheat starch, was reduced after addition of TPS, TSE, and TSS, respectively, but was increased by GTP. Furthermore, the half crystallization time in the Avrami equation almost doubled after the separate addition of the tea derivatives.
Xue, Dong; Yao, Huai-Ying; Huang, Chang-Yong
In this paper, the total microbial DNA was extracted from the soils in 8-, 50- and 90 years old tea orchards, adjacent wasteland, and 90 years old forestland in Meijiawu tea area of Hangzhou. The 16S rDNA V3 fragment was amplified by PCR, and the polymorphism of this fragment was analyzed by DGGE. The results indicated that both the tea orchard age and the land use type had significant effects on soil microbial genetic diversity. There was a significant difference (P < 0.05) in the microbial genetic diversity index among wasteland, tea orchards and forestland, which was decreased in the order of wasteland > tea orchard > forestland. For the tea orchards of different ages, the soil microbial genetic diversity index, microbial biomass C, and basal respiration were significantly higher in 50 years old than in 8 and 90 years old tea orchards.
Chan, J T; Koh, S H
The fluoride contents of infusions prepared from 44 different brands and types of teas were measured. Fluoride concentrations ranged from 0.34 to 3.71 ppm (mean = 1.50 ppm) in caffeinated tea infusions, 0.02-0.14 ppm (mean = 0.05 ppm) in herbal tea infusions, and 1.01-5.20 ppm (mean = 3.19) in decaffeinated tea infusions. This is the first report of the fluoride content of decaffeinated teas. The mean fluoride content of decaffeinated tea infusions is significantly (p < 0.01) higher than the corresponding caffeinated tea. The use of mineral water containing a naturally high fluoride level during the process of decaffeination is the most likely explanation of the above observation.
Hashimoto, Takashi; Goto, Miho; Sakakibara, Hiroyuki; Oi, Naomi; Okamoto, Mayumi; Kanazawa, Kazuki
The present study compared the effects of six Chinese teas categorized by their production process: green, white, yellow, oolong, black and pu-erh teas, on carbon tetrachloride (CCl4)-induced liver injury. Wistar rats were given ad libitum the Chinese teas prepared according to the home-style methods for 1 week, and then intraperitoneally injected with CCl4 (1 mg/kg body weight) or olive oil as a vehicle. The yellow tea significantly ameliorated the increase in the activity of the alanine- and aspartate-aminotransferases in plasma. Thus, the drinking of yellow tea may contribute to protection against liver injury.
Green, Rodney J; Murphy, Angus S; Schulz, Burkhard; Watkins, Bruce A; Ferruzzi, Mario G
Epidemiological evidence suggests a role for tea catechins in reduction of chronic disease risk. However, stability of catechins under digestive conditions is poorly understood. The objective of this study was to characterize the effect of common food additives on digestive recovery of tea catechins. Green tea water extracts were formulated in beverages providing 4.5, 18, 23, and 3.5 mg per 100 mL epicatechin (EC), epigallocatechin (EGC), epigallocatechin-gallate (EGCG), and epicatechin-gallate (ECG), respectively. Common commercial beverage additives; citric acid (CA), BHT, EDTA, ascorbic acid (AA), milk (bovine, soy, and rice), and citrus juice (orange, grapefruit, lemon, and lime) were formulated into finished tea beverages at incremental dosages. Samples were then subjected to in vitro digestion simulating gastric and small intestinal conditions with pre- and post-digestion catechin profiles assessed by HPLC. Catechin stability in green tea was poor with <20% total catechins remaining post-digestion. EGC and EGCG were most sensitive with less, not double equals 10% recovery. Teas formulated with 50% bovine, soy, and rice milk increased total catechin recovery significantly to 52, 55, and 69% respectively. Including 30 mg AA in 250 mL of tea beverage significantly (p<0.05) increased catechin recovery of EGC, EGCG, EC, and ECG to 74, 54, 82, and 45% respectively. Juice preparation resulted in the highest recovery of any formulation for EGC (81-98%), EGCG (56-76%), EC (86-95%), and ECG (30-55%). These data provide evidence that tea consumption practices and formulation factors likely impact catechin digestive recovery and may result in diverse physiological profiles.
Gouvea, Alfredo de; Bertoldo, Guilherme; Alves, Luis F A
Mite infestations to the culture of mate-tea frequently causes losses by the premature fall of the leaves. So, it is necessary to monitor the population of these arthropods, and to adopt management strategies for their control. The objective of this research was to evaluate the trustworthiness of presence-absence sampling for Oligonychus yothersi (McGregor) on mate-tea orchard. This study was conducted in Cascavel, Paraná State, from April 2001 to July 2000, in a mate-tea tree commercial plantation. Biweekly sampling of 240 leaves were collected in different parts of 10 plants, and the number of mites was counted. The aggregation pattern was determined through the coefficients a and b of Taylor's power law. The proportion of infested leaves and the number of required samples were estimated through mathematical model. The mite O. yothersi presented aggregate distribution. The proportion of infested leaves calculated by means of mathematical model showed to be a trustworthy parameter to estimate the population density of the mite. The number of required samples was small, making feasible the practical application of the presence-absence sampling method for O. yothersi in the culture of mate-tea.
Li, Lanhai; Fu, Qing-Long; Achal, Varenyam; Liu, Yonglin
Heavy metals and Al in tea products are of increasing concern. In this study, contents of Al, Cd, Co, Cr, Cu, Ni, and Pb in commercially available green tea and its infusions were measured by ICP-MS and ICP-AES. Both target hazard quotient (THQ) and hazard index (HI) were employed to assess the potential health risk of studied metals in tea leaves and infusions to drinkers. Results showed that the average contents of Al, Cd, Co, Cr, Cu, Ni, and Pb in tea leaves were 487.57, 0.055, 0.29, 1.63, 17.04, 7.71, and 0.92 mg/kg, respectively. Except for Cu, metal contents were within their maximum limits (1, 5, 30, and 5 mg/kg for Cd, Cr, Cu, and Pb, respectively) of current standards for tea products. Concentrations of metals in tea infusions were all below their maximum limits (0.2, 0.005, 0.05, 1.0, 0.02, and 0.01 mg/L for Al, Cd, Cr(VI), Cu, Ni, and Pb, respectively) for drinking water, and decreased with the increase of infusion times. Pb, Cd, Cu, and Al mainly remained in tea leaves. The THQ from 2.33 × 10(-5) to 1.47 × 10(-1) and HI from1.41 × 10(-2) to 3.45 × 10(-1) values in tea infusions were all less than 1, suggesting that consumption of tea infusions would not cause significant health risks for consumers. More attention should be paid to monitor Co content in green tea. Both THQ and HI values decreased with the increase of infusion times. Results of this study suggest that tea drinkers should discard the first tea infusion and drink the following infusions.
Chou, C C; Lin, L L; Chung, K T
Bacillus subtilis, Escherichia coli, Proteus vulgaris, Pseudomonas fluorescens, Salmonella sp. and Staphylococcus aureus were used to test the antimicrobial activity of tea flush extract and extracts of various tea products. Among the six test organisms, P. fluorescens was the most sensitive to the extracts, while B. subtilis was the least sensitive. In general, antimicrobial activity decreased when the extents of tea fermentation increased. The antimicrobial activities of tea flush extract and extracts of tea products with different extents of fermentation varied with test organisms. Tea flush and Green tea, the unfermented tea, exerted the strongest antimicrobial activity followed by the partially fermented tea products such as Longjing, Tieh-Kuan-Ying, Paochung, and Oolong teas. On the other hand, Black tea, the completely fermented tea, showed the least antimicrobial activity. It was also noted that extracts of Oolong tea prepared in summer exhibited the strongest antimicrobial activity, followed by those prepared in spring, winter and fall.
Fan, Dong-Mei; Fan, Kai; Yu, Cui-Ping; Lu, Ya-Ting; Wang, Xiao-Chang
Polyphenols are one of the most important secondary metabolites, and affect the decomposition of litter and soil organic matter. This study aims to monitor the mass loss rate of tea leaf litter and nutrient release pattern, and investigate the role of tea polyphenols played in this process. High-performance liquid chromatography (HPLC) and classical litter bag method were used to simulate the decomposition process of tea leaf litter and track the changes occurring in major polyphenols over eight months. The release patterns of nitrogen, potassium, calcium, and magnesium were also determined. The decomposition pattern of tea leaf litter could be described by a two-phase decomposition model, and the polyphenol/N ratio effectively regulated the degradation process. Most of the catechins decreased dramatically within two months; gallic acid (GA), catechin gallate (CG), and gallocatechin (GC) were faintly detected, while others were outside the detection limits by the end of the experiment. These results demonstrated that tea polyphenols transformed quickly and catechins had an effect on the individual conversion rate. The nutrient release pattern was different from other plants which might be due to the existence of tea polyphenols.
Fan, Dong-mei; Fan, Kai; Yu, Cui-ping; Lu, Ya-ting; Wang, Xiao-chang
Polyphenols are one of the most important secondary metabolites, and affect the decomposition of litter and soil organic matter. This study aims to monitor the mass loss rate of tea leaf litter and nutrient release pattern, and investigate the role of tea polyphenols played in this process. High-performance liquid chromatography (HPLC) and classical litter bag method were used to simulate the decomposition process of tea leaf litter and track the changes occurring in major polyphenols over eight months. The release patterns of nitrogen, potassium, calcium, and magnesium were also determined. The decomposition pattern of tea leaf litter could be described by a two-phase decomposition model, and the polyphenol/N ratio effectively regulated the degradation process. Most of the catechins decreased dramatically within two months; gallic acid (GA), catechin gallate (CG), and gallocatechin (GC) were faintly detected, while others were outside the detection limits by the end of the experiment. These results demonstrated that tea polyphenols transformed quickly and catechins had an effect on the individual conversion rate. The nutrient release pattern was different from other plants which might be due to the existence of tea polyphenols. PMID:28124839
Leung, L K; Su, Y; Chen, R; Zhang, Z; Huang, Y; Chen, Z Y
Green tea catechins, including (-)-epicatechin (EC), (-)-epicatechin gallate (ECG), (-)-epigallocatechin (EGC) and (-)-epigallocatechin gallate (EGCG), are oxidized and dimerized during the manufacture of black tea and oolong tea to form orange-red pigments, theaflavins (TF), a mixture of theaflavin (TF1), theaflavin-3-gallate (TF2A), theaflavin-3'-gallate (TF2B) and theaflavin-3,3'-digallate (TF3). The present study was designed to compare the antioxidant activities of individual TF with that of each catechin using human LDL oxidation as a model. All catechins and TF tested inhibited Cu(+2)-mediated LDL oxidation. Analysis of the thiobarbituric acid-reactive substances (TBARS) and conjugated dienes produced during LDL oxidation revealed that the antioxidant activity was in the order: TF3 > ECG > EGCG > or = TF2B > or = TF2A > TF1 > or = EC > EGC. Four TF derivatives also demonstrated a dose-dependent antioxidant activity in Cu(+2)-mediated LDL oxidation at concentrations of 5-40 micromol/L. These results demonstrate that the TF present in black tea possess at least the same antioxidant potency as catechins present in green tea, and that the conversion of catechins to TF during fermentation in making black tea does not alter significantly their free radical-scavenging activity.
Zhou, Yi-Bin; Wan, Xiao-Chun; Shang, Yan-Yan; Hu, Jing-Wei; Shao, Lei; Chen, Wei; Li, Da-Xiang
Metabolic profiles of broiler chickens were examined after the ingestion of green tea, tea polyphenols, and (-)-epigallocatechin-3-gallate (EGCG). Solid-phase extraction of serum and litters yielded free catechins and their metabolites, which were then identified and quantified by liquid chromatography-tandem mass spectrometry. In plasma samples, (-)-gallocatechin, (+)-catechin, and EGCG were detected in the green tea group; pyrogallol acid, (epi)catechin-O-sulfate, 4'-O-methyl-(epi)gallocatechin-O-glucuronide, and (epi)catechin-3'-O-glucuronide were detected in the tea polyphenols group; and EGCG, (-)-gallocatechin gallate (GCG), and 4'-O-methyl-(epi)gallocatechin-O-glucuronides were detected in the EGCG group. In litters, gallic acid, EGCG, GCG, and ECG were detected in the green tea and tea polyphenols groups; EGCG and ECG were detected in the EGCG group. The conjugated metabolites, 4'-O-methyl-(epi)gallocatechin-O-glucuronide, (epi)catechin-3'-glucuronide, and 4'-O-methyl-(epi)catechin-O-sulfate, were identified in the green tea group; 4'-O-methyl-(epi)catechin-O-sulfate and 4'-O-methyl-(epi)gallocatechin-O-sulfate were identified in the tea polyphenols group; only 4'-O-methyl-(epi)gallocatechin-O-sulfate was detected in the EGCG group. The excretion of tea catechins was 95.8, 87.7, and 97.7% for the green tea, tea polyphenols, and EGCG groups, respectively.
Gao, Guanwei; Chen, Hongping; Liu, Pingxiang; Hao, Zhenxia; Ma, Guicen; Chai, Yunfeng; Wang, Chen; Lu, Chengyin
Residues of polycyclic aromatic hydrocarbons (PAHs) in green tea and tea infusion were determined using gas chromatography-tandem mass spectrometry to study their dissipation pattern during green tea processing and infusion. Concentration and evaporation of PAHs during tea processing were the key factors affecting PAH residue content in product intermediates and in green tea. PAH residues in tea leaves increased by 2.4-3.1 times during the manufacture of green tea using the electric heating model. After correction to dry weight, PAH residue concentrations decreased by 33.5-48.4% during green tea processing because of PAH evaporation. Moreover, spreading and drying reduced PAH concentrations. The transfer rates of PAH residues from green tea to infusion varied from 4.6% to 7.2%, and PAH leaching was higher in the first infusion than in the second infusion. These results are useful for assessing exposure to PAHs from green tea and in formulating controls for the maximum residue level of PAHs in green tea.
Miyazaki, Hideo; Yamaguchi, Kouzou; Uchino, Toshitaka
Kamairicha (pan fired tea), Tama-ryokucha (steamed tea) and Sencha were made from same raw leaves of tea and their chromatic characteristics were analyzed. The luster of crude tea and the infusion color of three types of tea were evaluated by measuring spectral reflectance and transmittance, respectively. The spectral reflectance of crude tea of Sencha was highest over the wave length and was followed by that of Tama-ryokucha. Comparing with Sencha, L* and b* values of Kamairicha were both lower whereas a* value was higher. While ,these color values of Tama-ryokucha were lower than those of Sencha and a* value was almost same. As for the tea season, L* and b* values of the second crop of tea were higher than the first crop. In addition, there were significant interactions between covering and tea type (tea manufacturing process) in L* and a* values. The spectral transmittance of infusion color of Kamairicha was highest over the wave length. L* value of Kamairicha was significantly higher than that of other two types of tea, and conversely b* value was lower. The comparison on between Tama-r yokucha and Sencha showed no significant difference in L*, a* and b* values of the infusion color.
Jenkins, Amanda J.; Llosa, Teobaldo; Montoya, Ivan
The consumption of coca tea is a common occurrence in many South American countries. The tea is often packaged in individual servings as tea bags which contain approximately 1 g of plant material. The consumption of coca tea leads to ingestion of cocaine and other alkaloids: however, there is little information available regarding the pharmacological or toxicological effects that result from consumption of coca tea. We performed a series of studies with coca tea bags from two South American countries, Peru and Bolivia. The alkaloidal content of the ‘coca leaf’ in coca tea bags was determined by two different extraction methods: Soxhlet extraction with methanol (exhaustive extraction), and mechanical agitation with methanol. Extracts were purified by solid-phase extraction (SPE) followed by analysis by gas chromatography/mass spectrometry (GC/MS). Coca tea prepared from Peruvian and Bolivian coca tea bags was also analyzed by SPE-GC/MS assay. In addition, urine specimens were analyzed from an individual who consumed one cup of Peruvian coca tea and one cup of Bolivian coca tea on separate occasions. Urine samples were analyzed by immunoassay (TDxR) and SPE-GC/MS. Analysis of coca tea bags and coca tea indicated that cocaine, benzoylecgonine, ecgonine methyl ester and trans-cinnamoylcocaine were present in varying quantities. With exhaustive extraction, an average of 5.11 mg, and 4.86 mg of cocaine per tea bag were found in coca leaf from Peru and Bolivia, respectively. The average amounts of benzoylecgonine and ecgonine methyl ester in Peruvian coca leaf were 0.11 and 1.15 mg, and in Bolivian coca leaf were 0.12 and 2.93 mg per tea bag, respectively. trans-Cinnamoylcocaine was found in trace amounts in Peruvian tea bags and 0.16 mg/tea bag of Bolivian tea. When tea was prepared, an average of 4.14 mg of cocaine was present in a cup of Peruvian coca tea and 4.29 mg of cocaine was present in Bolivian tea. Following the consumption of a cup of Peruvian tea by one
Jenkins, A J; Llosa, T; Montoya, I; Cone, E J
The consumption of coca tea is a common occurrence in many South American countries. The tea is often packaged in individual servings as tea bags which contain approximately 1 g of plant material. The consumption of coca tea leads to ingestion of cocaine and other alkaloids; however, there is little information available regarding the pharmacological or toxicological effects that result from consumption of coca tea. We performed a series of studies with coca tea bags from two South American countries, Peru and Bolivia. The alkaloidal content of the 'coca leaf' in coca tea bags was determined by two different extraction methods: Soxhlet extraction with methanol (exhaustive extraction), and mechanical agitation with methanol. Extracts were purified by solid-phase extraction (SPE) followed by analysis by gas chromatography/mass spectrometry (GC/MS). Coca tea prepared from Peruvian and Bolivian coca tea bags was also analyzed by SPE-GC/MS assay. In addition, urine specimens were analyzed from an individual who consumed one cup of Peruvian coca tea and one cup of Bolivian coca tea on separate occasions. Urine samples were analyzed by immunoassay (TDx) and SPE-GC/MS. Analysis of coca tea bags and coca tea indicated that cocaine, benzoylecgonine, ecgonine methyl ester and trans-cinnamoylcocaine were present in varying quantities. With exhaustive extraction, an average of 5.11 mg, and 4.86 mg of cocaine per tea bag were found in coca leaf from Peru and Bolivia, respectively. The average amounts of benzoylecgonine, ecgonine methyl ester in Peruvian coca leaf were 0.11 and 1.15 mg, and in Bolivian coca leaf were 0.12 and 2.93 mg per tea bag, respectively. trans-cinnamoylcocaine was found in trace amounts in Peruvian tea bags and 0.16 mg/tea bag of Bolivian tea. When tea was prepared, an average of 4.14 mg of cocaine was present in a cup of Peruvian coca tea and 4.29 mg of cocaine was present in Bolivian tea. Following the consumption of a cup of Peruvian tea by one
Rosal, Lorenca Consuelo; And Others
A teachers' guide is presented that accompanies the video production of "The Other Boston Tea Party," a play used to teach about the U.S. Constitution and American legal and political systems. The play combines a comedy of manners with an historical approach to the issues surrounding the Federalist/Anti-Federalist debate over…
Presents statistics on the most commonly held stereotypes in Germany of Britain and the British including drinking a lot of tea, eating bacon and eggs for breakfast, consumption of whiskey and beer, and the occurrence of fog in England. Suggests these stereotypes were developed in the early 1950s and are not as prevalent today. (BK)
Rosal, Lorenca Consuelo; And Others
A teachers' guide is presented that accompanies the video production of "The Other Boston Tea Party," a play used to teach about the U.S. Constitution and American legal and political systems. The play combines a comedy of manners with an historical approach to the issues surrounding the Federalist/Anti-Federalist debate over…
The Teacher Center at the University of Houston-Clear Lake (Texas) invites public school supervisors who work with their student teachers, and any other teachers who are interested in supervising student teachers, to a High Tea/inservice program each semester. In planning the inservice program, the organizers first look at evaluations from…
Lursmanashvili, L; Gulua, L; Turmanidze, T; Enukidze, M; Machavariani, M; Sanikidze, T
The purpose of our study was to determine effects of green tea extracts on the Jurkat cells incubated under oxidative stress conditions. The research was conducted on leukemic human mature T cells (Jurkat cells). For the modelling of oxidative stress 30% hydrogen peroxide (H2O2) (Sigma) (10 μl, 25 μl 50 μl and 100 μl) was added to Jurkat cell suspension with subsequent incubation for 4, 6, 8 and 24 h. Control group was represented by intact Jurkat cells. The assessment of cells proliferation activity (viability) was performed by MTT test. The viability of Jurkat cells incubated for 24 hours under acquit oxidative stress conditions dose-depenently, monotonically decreased (irreversibly at 100 μM of H2O2 and reaches the 30% of intact Jurkat cells viability level at 50 μM of H2O2). Low doses of H2O2 (10 μl, 25 μl H2O2) revealed cytotoxicity only within short term (8 hours) of the incubation, afterward the viability of Jurkat cells monotonically increased and after 24 hours it reached 43% and 56% of control level, respectively. Vitamins C and E revealed cytotoxic effect on intact Jurkat cells, while the C+V vitamins complex induced 2-fold stimulation of Jurkat cells viability. Under a moderate oxidative stress condition (25 μl of H2O2) the complex of C + E vitamins revealed cytoprotective effect on Jurkat cells which may be related to ability of vitamin C to induce regeneration and to transform E vitamin tocopheroxyl free radicals into tocopherol. Green tea had no effect, green tea catechins revealed stimulatory effect, while green tea pectin - weak cytotoxic effect on intact Jurkat cells. Green tea and especially extracted catechins (but not pectin) revealed stimulatory effect on the viability of the Jurkat cells incubated under an oxidative stress condition. Our study results confirm the opinion that the natural compounds (green tea extracts) are harmless for normal cellular metabolism. Their differential effects on the "diseased", incubated under an
Fisler, Marie; Lecointre, Guillaume
The aim of this study is to explore whether matrices and MP trees used to produce systematic categories of organisms could be useful to produce categories of ideas in history of science. We study the history of the use of trees in systematics to represent the diversity of life from 1766 to 1991. We apply to those ideas a method inspired from coding homologous parts of organisms. We discretize conceptual parts of ideas, writings and drawings about trees contained in 41 main writings; we detect shared parts among authors and code them into a 91-characters matrix and use a tree representation to show who shares what with whom. In other words, we propose a hierarchical representation of the shared ideas about trees among authors: this produces a "tree of trees." Then, we categorize schools of tree-representations. Classical schools like "cladists" and "pheneticists" are recovered but others are not: "gradists" are separated into two blocks, one of them being called here "grade theoreticians." We propose new interesting categories like the "buffonian school," the "metaphoricians," and those using "strictly genealogical classifications." We consider that networks are not useful to represent shared ideas at the present step of the study. A cladogram is made for showing who is sharing what with whom, but also heterobathmy and homoplasy of characters. The present cladogram is not modelling processes of transmission of ideas about trees, and here it is mostly used to test for proximity of ideas of the same age and for categorization.
Datta, Abhinandya; Grün, Ingolf U; Kwasniewski, Misha T; Fernando, Lakdas N
Bitterness reduction, especially of foods and beverages containing phytonutrients, is one of the biggest challenges in the food industry because bitterness has a deleterious effect on the taste profile of foods and beverages. Neem (Azadirachta indica A. Juss) is a medicinal tree, indigenous to the Indian-subcontinent, whose medicinal properties have led to it being heralded as the tree which is the "panacea for all diseases". However, neem leaf is extremely bitter, in large part due to its limonoid content, making it unpalatable. The objective of this study was to apply two adsorbent based strategies, namely solid phase extraction (SPE) and Amberlite XAD-16 (AMB) resin, to achieve de-bittering of neem tea and to determine the effects of the de-bittering on the bio-active, color and volatile properties. The solid SPE treatment completely removed the flavonol, quercetin, from neem tea while in Amberlite XAD-16 treated tea (AMB) it was only insignificantly (p > 0.05) reduced. We also observed decreases in total phenolic content and consequently anti-oxidant activities after de-bittering. A 62% mean reduction of limonoid aglycones indicated diminished levels of bitterness. The loss of phenolics lead to a visually appreciable color changes in the treated teas. The de-bittering also leads to a loss of sesquiterpenes, ketones and acids from neem tea. In conclusion, we found that while SPE cartridges were more efficient in removing bitterness, they caused a greater reduction in bio-active compounds than AMB XAD-16 resins, which may ultimately affect the health properties of neem tea.
Zhou, Quan; Li, Hui; Zhou, Jian-Guo; Ma, Yuan; Wu, Tao; Ma, Hu
Several studies have assessed the association between green and black tea consumption and the risk of endometrial cancer (EC) and have yielded inconsistent results. The purpose of this meta-analysis is to systematically analyze the effect of green tea and black tea on EC risk. PubMed, Embase, Cochrane Library and China Biological Medicine Database were searched through February 2, 2015 to identify studies that met pre-stated inclusion criteria. Overall relative risk (RR) was estimated based on the highest and lowest levels of green/black tea consumption. Dose-response relationships were evaluated with the data from categories of green/black tea intake in each study. For green tea, the summary RR indicated that the highest green tea consumption was associated with a reduced risk of EC (RR 0.78, 95 % CI 0.66-0.92). Furthermore, an increase in green tea consumption of one cup per day was associated with an 11 % decreased risk of developing EC. (RR 0.89, 95 % CI 0.84-0.94). For black tea, no statistically significant association was observed in the meta-analysis (highest versus non/lowest, RR 0.99, 95 % CI 0.79-1.23; increment of one cup/day, RR 0.99, 95 % CI 0.94-1.03). The power of the estimate of green tea and black tea with risk of EC was 84.33 and 5.07 %, respectively. The quality of evidence for the association between green and black tea with EC risk was moderate and very low, respectively. The results from this meta-analysis indicate that green tea, but not black tea, may be related to a reduction of EC risk. Large population-based randomized controlled trials and large prospective cohort studies are required to obtain a definitive conclusion and determine the mechanisms underlying this association.
Vogt, Peter R.
Nature often replicates her processes at different scales of space and time in differing media. Here a tree-trunk cross section I am preparing for a dendrochronological display at the Battle Creek Cypress Swamp Nature Sanctuary (Calvert County, Maryland) dried and cracked in a way that replicates practically all the planform features found along the Mid-Oceanic Ridge (see Figure 1). The left-lateral offset of saw marks, contrasting with the right-lateral ``rift'' offset, even illustrates the distinction between transcurrent (strike-slip) and transform faults, the latter only recognized as a geologic feature, by J. Tuzo Wilson, in 1965. However, wood cracking is but one of many examples of natural processes that replicate one or several elements of lithospheric plate tectonics. Many of these examples occur in everyday venues and thus make great teaching aids, ``teachable'' from primary school to university levels. Plate tectonics, the dominant process of Earth geology, also occurs in miniature on the surface of some lava lakes, and as ``ice plate tectonics'' on our frozen seas and lakes. Ice tectonics also happens at larger spatial and temporal scales on the Jovian moons Europa and perhaps Ganymede. Tabletop plate tectonics, in which a molten-paraffin ``asthenosphere'' is surfaced by a skin of congealing wax ``plates,'' first replicated Mid-Oceanic Ridge type seafloor spreading more than three decades ago. A seismologist (J. Brune, personal communication, 2004) discovered wax plate tectonics by casually and serendipitously pulling a stick across a container of molten wax his wife and daughters had used in making candles. Brune and his student D. Oldenburg followed up and mirabile dictu published the results in Science (178, 301-304).
Tamaru, Shizuka; Ohmachi, Kazuhiro; Miyata, Yuji; Tanaka, Takashi; Kubayasi, Takashi; Nagata, Yasuo; Tanaka, Kazunari
Fermented mixed tea made with third-crop green tea leaves and camellia leaves by a tea-rolling process has been developed. The objective of this study was to investigate hypotriglyceridemic potential of the mixed tea in rats. The mixed tea contained theasinensins and theaflavins. Rats fed the mixed tea extract at the level of 1% exerted significantly lower body weight and adipose tissue weight compared to animals fed third-crop green tea or camellia tea extract alone for 4 weeks. Serum and hepatic triglyceride was significantly and dose-dependently decreased by the mixed tea. This decrease was associated with lowered lipogenic enzyme activities in the liver. Furthermore, an oral administration of 4 or 8% of the mixed tea extract followed by fat emulsion suppressed the increment of serum triglyceride level. These results suggest that the mixed tea has hypotriglyceridemic action, partially via delaying triglyceride absorption in the small intestine and repressing hepatic lipogenic enzymes.
E. Gregory McPherson; Paula J. Peper
This paper describes three long-term tree growth studies conducted to evaluate tree performance because repeated measurements of the same trees produce critical data for growth model calibration and validation. Several empirical and process-based approaches to modeling tree growth are reviewed. Modeling is more advanced in the fields of forestry and...
Kevin T. Smith
Landscape trees have real value and contribute to making livable communities. Making the most of that value requires providing trees with the proper care and attention. As potentially large and long-lived organisms, trees benefit from commitment to regular care that respects the natural tree system. This system captures, transforms, and uses energy to survive, grow,...
Boyd, Amy E.; Cooper, Jim
Tree rings can be used not only to look at plant growth, but also to make connections between plant growth and resource availability. In this lesson, students in 2nd-4th grades use role-play to become familiar with basic requirements of trees and how availability of those resources is related to tree ring sizes and tree growth. These concepts can…
Boyd, Amy E.; Cooper, Jim
Tree rings can be used not only to look at plant growth, but also to make connections between plant growth and resource availability. In this lesson, students in 2nd-4th grades use role-play to become familiar with basic requirements of trees and how availability of those resources is related to tree ring sizes and tree growth. These concepts can…
Truong, S. K.; Karim, R.
The chief objectives of this experiment are to distinguish which type of tea of four variants, pomegranate blackberry green, green, lemon chamomile (herbal), and earl grey (black), are capable of chelating the most iron (III) chloride (FeCl3) through titration. We hypothesized that if each tea variety chelates differing amounts of iron chloride, and if we conduct an experiment in which four different teas are mixed in the same amount of water, iron chloride, and iron chloride indicator EDTA, then the pomegranate blackberry green tea will bind to the most iron due to its large amount of fruit antioxidants. To summarize our methodology, we prepared three solutions of each tea, dissolved with 1 gram of FeCl3 to test three trials per tea variety. The chelation process took place overnight as teas cooled. Six drops of iron chloride indicator added to each solution began the titration. The necessary amount of 0.1M EDTA (ethylenediaminetetraacetic acid) drops required for each solution to turn to a universal amber color from its original dark tone indicates how many free iron molecules were left unbound by the tea solution. After careful analysis of the data, we discovered that blackberry pomegranate green tea possessed the best chelating abilities with 97.48% of FeCl3 adsorbed. Green tea followed with 96.67%. Herbal tea chelated 94.24% of the iron while earl grey absorbed the least amount at 93.43%. From our conclusion, we drew that since blackberry pomegranate green tea contained the highest amount of polyphenols and antioxidants as well as epigallocatechin gallate (EGCG) found in green teas, it was able to chelate the most amount of iron. The substances mentioned in blackberry pomegranate green tea possess the ability to form strong bonds with multiple heavy metals, such as iron (III) chloride atoms. Overall, each variety of tea contains different organic substances. Each of these substances possesses a unique chelating ability, determining how well the type of tea can
Ma, Junfeng; Li, Zhe; Xing, Shu; Ho, Wanting Tina; Fu, Xueqi; Zhao, Zhizhuang Joe
Tea is widely consumed all over the world. Studies have demonstrated the role of tea in prevention and treatment of various chronic diseases including diabetes and obesity, but the underlying mechanism is unclear. PTP1B is a widely expressed tyrosine phosphatase which has been defined as a target for therapeutic drug development to treat diabetes and obesity. In screening for inhibitors of PTP1B, we found that aqueous extracts of teas exhibited potent PTP1B inhibitory effects with an IC50 value of 0.4 to 4 g dry tea leaves per liter of water. Black tea shows the strongest inhibition activities, followed by oolong and then by green tea. Biochemical fractionations demonstrated that the major effective components in tea corresponded to oxidized polyphenolic compounds. This was further verified by the fact that tea catechins became potent inhibitors of PTP1B upon oxidation catalyzed by tyrosinases. When applied to cultured cells, tea extracts induced tyrosine phosphorylation of cellular proteins. Our study suggests that some beneficial effects of tea may be attributed to the inhibition of PTP1B. PMID:21371422
Green tea contains high concentrations of tea polyphenols that have shown inhibitory effects against the development, progress, and growth of carcinogen-induced tumors in animal models at different organ sites, including the esophagus and lung. Green tea polyphenols also have shown to suppress cell proliferation and induce apoptosis. Besides antioxidative property, green tea polyphenols have pro-oxidative activities under certain conditions and modulate phase II metabolic enzymes that can enhance the detoxification pathway of environmental toxicants and carcinogens. Although epidemiological studies have provided inconclusive results on the effect of green tea consumption against the development of esophageal and lung cancers in humans overall, the inverse association between green tea intake and risk of esophageal cancer risk is more consistently observed in studies with adequate control for potential confounders. Epidemiological studies also have demonstrated an inverse, albeit moderate, association between green tea consumption and lung cancer, especially in non-smokers. This article reviews data on the cancer-preventive activities of green tea extract and green tea polyphenols and possible mechanisms against the esophageal and lung carcinogenesis in experimental animals, and summarizes the current knowledge from epidemiological studies on the relationship between green tea consumption and esophageal and lung cancer risk in humans. PMID:21538848
Yuan, Jian-Min; Sun, Canlan; Butler, Lesley M.
Experimental studies have consistently shown the inhibitory activities of tea extracts on tumorigenesis in multiple model systems. Epidemiologic studies, however, have produced inconclusive results in humans. A comprehensive review was conducted to assess the current knowledge on tea consumption and risk of cancers in humans. In general, consumption of black tea was not associated with lower risk of cancer. High intake of green tea was consistently associated with reduced risk of upper gastrointestinal tract cancers after sufficient control for confounders. Limited data support a protective effect of green tea on lung and hepatocellular carcinogenesis. Although observational studies do not support a beneficial role of tea intake on prostate cancer risk, phase II clinical trials have demonstrated an inhibitory effect of green tea extract against the progression of prostate pre-malignant lesions. Green tea may exert beneficial effects against mammary carcinogenesis in premenopausal women and recurrence of breast cancer. There is no sufficient evidence that supports a protective role of tea intake on the development of cancers of the colorectum, pancreas, urinary tract, glioma, lymphoma, and leukemia. Future prospective observational studies with biomarkers of exposure and phase III clinical trials are required to provide definitive evidence for the hypothesized beneficial effect of tea consumption on cancer formation in humans. PMID:21419224
Sano, M; Suzuki, M; Miyase, T; Yoshino, K; Maeda-Yamamoto, M
Two catechin derivatives (C-1 and C-2) with potent antiallergic activity were isolated from Taiwanese oolong tea by HPLC techniques. From NMR and FAB-MS analyses, the structures of C-1 and C-2 were elucidated as (-)-epigallocatechin 3-O-(3-O-methyl)gallate and (-)-epigallocatechin 3-O-(4-O-methyl)gallate, respectively. The oolong tea leaves contained 0.34% (dry weight) C-1 and 0.20% C-2. Traces of C-2 were detected in only 1 of 15 varieties of green tea tested. C-1 was detected in 13 of 15 green tea varieties; C-1 was most concentrated in tea cultivars classified as Assam hybrids (0. 50-0.82% of dry weight). Quantitative analyses of green tea, oolong tea, and black tea manufactured from same batches of tea leaves showed that neither catechin derivative was produced during the fermentation process. Oral doses of C-1 and C-2 (5-50 mg/kg) significantly inhibited type I allergic (anaphylactic) reactions in mice sensitized with ovalbumin and Freund's incomplete adjuvant. These inhibitory effects exceeded that of the major tea catechin, (-)-epigallocatechin 3-O-gallate, which has known antiallergic properties.
Malir, Frantisek; Ostry, Vladimir; Pfohl-Leszkowicz, Annie; Toman, Jakub; Bazin, Ingrid; Roubal, Tomas
Ochratoxin A (OTA) is nephrotoxic, hepatotoxic, immunotoxic, neurotoxic, reprotoxic, teratogenic, and carcinogenic (group 2B), being characterized by species and sex differences in sensitivity. Despite the fact that OTA is in some aspects a controversial topic, OTA is the most powerful renal carcinogen. The aim of this study was to make a small survey concerning OTA content in black tea, fruit tea, and ground roasted coffee, and to assess OTA transfer into beverages. OTA content was measured using a validated and accredited HPLC-FLD method with a limit of quantification (LOQ) of 0.35 ng/g. The OTA amount ranged from LOQ up to 250 ng/g in black tea and up to 104 ng/g in fruit tea. Black tea and fruit tea, naturally contaminated, were used to prepare tea infusions. The transfer from black tea to the infusion was 34.8% ± 1.3% and from fruit tea 4.1% ± 0.2%. Ground roasted coffee naturally contaminated at 0.92 ng/g was used to prepare seven kinds of coffee beverages. Depending on the type of process used, OTA transfer into coffee ranged from 22.3% to 66.1%. OTA intakes from fruit and black tea or coffee represent a non-negligible human source. PMID:25525684
Green, Chadwick John; de Dauwe, Palina; Boyle, Terry; Tabatabaei, Seyed Mehdi; Fritschi, Lin; Heyworth, Jane Shirley
Data regarding the effects of tea, coffee, and milk on the risk of colorectal cancer are inconsistent. We investigated associations of tea, coffee, and milk consumption with colorectal cancer risk and attempted to determine if these exposures were differentially associated with the risks of proximal colon, distal colon, and rectal cancers. Data from 854 incident cases and 948 controls were analyzed in a case-control study of colorectal cancer in Western Australia during 2005-07. Multivariable logistic regression was used to analyze the associations of black tea (with and without milk), green tea, herbal tea, hot coffee, iced coffee, and milk with colorectal cancer. Consumption of 1 or more cups of herbal tea per week was associated with a significantly decreased risk of distal colon cancer (adjusted odds ratio, 0.37; 95% CI, 0.16-0.82; PTrend = 0.044), and consumption of 1 or more cups of iced coffee per week was associated with increased risk of rectal cancer (adjusted odds ratio, 1.52; 95% CI, 0.91-2.54; PTrend = 0.004). Neither herbal tea nor iced coffee was associated with the risk of proximal colon cancer. Hot coffee was associated with a possible increased risk of distal colon cancer. Black tea (with or without milk), green tea, decaffeinated coffee, and milk were not significantly associated with colorectal cancer risk. Consumption of herbal tea was associated with reduced risk of distal colon cancer, and consumption of iced coffee was associated with increased rectal cancer risk.
Green tea contains high concentrations of tea polyphenols that have shown inhibitory effects against the development, progress, and growth of carcinogen-induced tumors in animal models at different organ sites, including the esophagus and lung. Green tea polyphenols also have shown to suppress cell proliferation and induce apoptosis. Besides antioxidative property, green tea polyphenols have pro-oxidative activities under certain conditions and modulate phase II metabolic enzymes that can enhance the detoxification pathway of environmental toxicants and carcinogens. Although epidemiological studies have provided inconclusive results on the effect of green tea consumption against the development of esophageal and lung cancers in humans overall, the inverse association between green tea intake and risk of esophageal cancer risk is more consistently observed in studies with adequate control for potential confounders. Epidemiological studies also have demonstrated an inverse, albeit moderate, association between green tea consumption and lung cancer, especially in non-smokers. This article reviews data on the cancer-preventive activities of green tea extract and green tea polyphenols and possible mechanisms against the esophageal and lung carcinogenesis in experimental animals, and summarizes the current knowledge from epidemiological studies on the relationship between green tea consumption and esophageal and lung cancer risk in humans.
Wang, Rong; Zhou, Weibiao
A green tea extract (GTE) was incorporated into bread as a source of tea catechins. The stability of tea catechins in the breadmaking process including unfrozen and frozen dough was studied. A method was developed for the separation and quantification of tea catechins in GTE, dough, and bread samples using a RP-HPLC system. The separation system consisted of a C18 reversed-phase column, a gradient elution system of water/methanol and formic acid, and a photodiode array UV detector. Tea catechins were detected at 275 nm. GTEs at 50, 100, and 150 mg per 100 g of flour were formulated. The results obtained showed that green tea catechins were relatively stable in dough during freezing and frozen storage at -20 degrees C for up to 9 weeks. There were no further detectable losses of tea catechins in bread during a storage of 4 days at room temperature. It was also revealed that (-)-epigallocatechin gallate (EGCG) and (-)-epigallocatechin (EGC) were more susceptible to degradation than (-)-epicatechin gallate (ECG) and (-)-epicatechin (EC). (-)-EGCG and (-)-ECG were normally selected as the quality indices of green tea catechins, and their retention levels in freshly baked bread were ca. 83 and 91%, respectively. One piece of bread (53 g) containing 150 mg of GTE/100 g of flour will provide 28 mg of tea catechins, which is approximately 35% of those infused from one green tea bag (2 g).
Malir, Frantisek; Ostry, Vladimir; Pfohl-Leszkowicz, Annie; Toman, Jakub; Bazin, Ingrid; Roubal, Tomas
Ochratoxin A (OTA) is nephrotoxic, hepatotoxic, immunotoxic, neurotoxic, reprotoxic, teratogenic, and carcinogenic (group 2B), being characterized by species and sex differences in sensitivity. Despite the fact that OTA is in some aspects a controversial topic, OTA is the most powerful renal carcinogen. The aim of this study was to make a small survey concerning OTA content in black tea, fruit tea, and ground roasted coffee, and to assess OTA transfer into beverages. OTA content was measured using a validated and accredited HPLC-FLD method with a limit of quantification (LOQ) of 0.35 ng/g. The OTA amount ranged from LOQ up to 250 ng/g in black tea and up to 104 ng/g in fruit tea. Black tea and fruit tea, naturally contaminated, were used to prepare tea infusions. The transfer from black tea to the infusion was 34.8% ± 1.3% and from fruit tea 4.1% ± 0.2%. Ground roasted coffee naturally contaminated at 0.92 ng/g was used to prepare seven kinds of coffee beverages. Depending on the type of process used, OTA transfer into coffee ranged from 22.3% to 66.1%. OTA intakes from fruit and black tea or coffee represent a non-negligible human source.
Hernández Figueroa, Tania T; Rodríguez-Rodríguez, Elena; Sánchez-Muniz, Francisco J
Tea (Camellia sinensis) has been used for centuries as a medical drink. Around two-thirds of the world's population drink tea. It is originated from southern China and entensive cultivated in Asia and in central African countries. Tea can be grouped into three main types, black, oolong, and green tea. Green tea is not fermented and is a major beverage consumed in Asian countries. Green tea is produced from freshly harvest leaves of the tea plant and they contain water, proteins, carbohydrates, minerals, vitamins and polyphenols of the flavonoid type. The major flavonoids in green tea are catechins which constitute about one third of its total dry weight. The major catechin present is epigallocatechin gallate (>50%). New data have increased the interest in green tea or its catechins and its role in treatment of cardiovascular disease (CHD) risk factors. The aim of the present paper is to review some studies that have found a relationship between green tea and CHD risk factors. From some of them it can be summarized that of green tea and its catechins consumptions (i) decrease body weight by interfering within the sympathoadrenal system and fatty acid synthesis, (ii) decrease cholesterol absorption and plasma levels, (iii) have strong free radical-scavenging activity inhibiting LDL oxidation, (iv) reduce the adhesion molecule expression, (v) have antitrombotic activities by inhibiting platelet aggregation and (vi) decrease systolic and diastolic blood pressures. The positive effects found suggest that a daily intake of 7 cups of green tea (3.5 g catechins) is a good choose for CHD prevention; however, it is still necessary more studies to check the action of the green tea and its catechins in humans in order to recommended its use in the general population or only in target subjects.
Lee, S M; Lee, H-S; Kim, K-H; Kim, K-O
Green tea has been widely consumed for its mild flavors and its health benefits, yet caffeine in green tea has been a limitation for those who want to avoid it. The limitation brought increase in need for decaffeinated products in the green tea market. Most of the conventional decaffeination techniques applied in food use organic solvents. However, supercritical carbon dioxide fluid extraction (SC-CO2) method is gaining its intension as one of the future decaffeination methods that overcomes the problems of conventional methods. The purpose of this study was to identify sensory characteristics of decaffeinated green teas applied with SC-CO2 method and to observe the relationship with consumer acceptability to elucidate the potentiality of applying SC-CO2 technique in decaffeinated green tea market. Descriptive analysis was performed on 8 samples: green teas containing 4 caffeine levels (10%, 35%, 60%, and 100%) infused at 2 infusing periods (1 or 2 min). It was found that the SC-CO2 process not only reduced caffeine but also decreased some important features of original tea flavors. Two groups were recruited for consumer acceptability test: one (GP I, N = 52), consuming all types of green teas including hot/cold canned teas; and the other (GP II, N = 40), only consuming the loose type. While GP II liked original green tea the most, GP I liked highly decaffeinated green teas. Although the SC-CO2 method had limitations of losing complex flavors of green teas, it appeared to have future potential in the decaffeinated green tea market within or without the addition of desirable flavors.
Robert E. Keane
The Tree Data (TD) methods are used to sample individual live and dead trees on a fixed-area plot to estimate tree density, size, and age class distributions before and after fire in order to assess tree survival and mortality rates. This method can also be used to sample individual shrubs if they are over 4.5 ft tall. When trees are larger than the user-specified...
Liu, Zhibin; Chen, Zhichao; Guo, Hongwen; He, Dongping; Zhao, Huiru; Wang, Zhiyao; Zhang, Wen; Liao, Lan; Zhang, Chen; Ni, Li
Tea consumption has been identified to have an anti-obesity effect. Whether it is associated with gut microbiota modulation is investigated in this study. Phenolic profiles of infusions of green tea, oolong tea and black tea were comprehensively compared first, by utilizing ultra-performance liquid chromatography-electrospray ionization-quadrupole time-of-flight mass spectrometry (UPLC-ESI-Q-TOFMS). Subsequently, high-fat-diet induced obese C57BL/6J mice were orally administered these three types of tea infusions for 13 weeks to evaluate their anti-obesity and gut microbiota modulatory effects. In general, 8 phenolic acids, 12 flavanols, 9 flavonols, 2 alkaloids and 1 amino acid were identified from the three types of tea infusions. Though they possess diverse phenolic compounds, no significant differences in the prevention of the development of obesity in high-fat-fed mice were discovered among the three types of tea. Based on high-throughput MiSeq sequencing and multivariate statistical analysis, it was revealed that tea infusion consumption substantially increased diversity and altered the structure of gut microbiota. The linear discriminant analysis effect size algorithm identified 30 key phylotypes in response to high-fat diet and tea, including Alistipes, Rikenella, Lachnospiraceae, Akkermansia, Bacteroides, Allobaculum, Parabacteroides, etc. Moreover, Spearman's correlation analysis indicated that these key phylotypes might have a close association with the obesity related indexes of the host. This study provides detailed information regarding the impact of tea consumption on gut microbiota, which may be helpful in understanding the anti-obesity mechanisms of tea.
Huang, Hsiu-Chen; Lin, Jen-Kun
Although green tea extract has been reported to suppress hyperlipidemia, it is unclear how tea extracts prepared from green, oolong, black and pu-erh teas modulate fatty acid synthase expression in rats fed on a high-fructose diet. In this animal study, we evaluated the hypolipidemic and hypoleptinemia effect of these four different tea leaves fed to male Wistar rats for 12 weeks. The results showed that a fructose-rich diet significantly elevated serum triacylglycerols, cholesterol, insulin, and leptin concentrations, as compared with those in the control group. Interestingly, consuming tea leaves for 12 weeks almost normalized the serum triacylglycerols concentrations. Again, rats fed with fructose/green tea and fructose/pu-erh tea showed the greatest reduction in serum TG, cholesterol, insulin and leptin levels. In contrast, serum cholesterol and insulin concentrations of the fructose/oolong tea-fed rats did not normalize. The relative epididymal adipose tissue weight was lower in all rats supplemented with tea leaves than those fed with fructose alone. There was molecular evidence of improved lipid homeostasis according to fatty acid synthase (FAS) protein expression. Furthermore, supplementation of green, black, and pu-erh tea leaves significantly decreased hepatic FAS mRNA and protein levels, and increased AMPK phosphorylation, compared with those of rats fed with fructose only. These findings suggest that the intake of green, black, and pu-erh tea leaves ameliorated the fructose-induced hyperlipidemia and hyperleptinemia state in part through the suppression of FAS protein levels and increased AMPK phosphorylation.
Korir, M W; Wachira, F N; Wanyoko, J K; Ngure, R M; Khalid, R
Several studies have demonstrated that tea flavonoids protect cells and tissues against free radicals which have been implicated in the etiology of oxidative stress-related disease disorders. However, black tea is commonly consumed with additives that could otherwise affect the bioavailability of the active tea molecules. In this study, the biochemical parameters of Kenyan teas were determined and the effect of added milk and sweeteners on the antioxidant activity of Kenyan teas was investigated. The effect of tea antioxidants on glutathione (GSH) was also evaluated in vivo in a time series study using Swiss mice. Green teas had the highest levels of total polyphenols, total and individual catechins, while black teas had high levels of total thearubigins, total theaflavins and theaflavin fractions. The antioxidant activity was high in green teas though some of the black teas were as efficacious as the green teas. The addition of milk, sugar and honey significantly (p<0.05) decreased the antioxidant activity of tea in a concentration-dependent manner. Addition of the sweetener, stevia (Stevia rebaudiana Bertoni), showed no significant (p>0.05) influence on the antioxidant activity of tea and therefore can be recommended as a preferred sweetener for tea. Significantly (p<0.001) higher levels of GSH were observed in plasma than in other tissues. GSH levels were generally highest 2h after tea consumption, which indicates the need to repeatedly take tea every 2h to maximise its potential health benefits.
Haidong, Liang; Fang, Yu; Zhihong, Tong; Changle, Ren
Microencapsulation of ethanol extract of tea was performed in this study. In order to microencapsulate, β-cyclodextrin was used as wall material. Ethanol extract of tea was used as the core material. Microcapsules in the solid form were obtained by drying the emulsions. RSM showed that optimal processing parameters were as followings: core material/wall material 1/4, β-cyclodextrin content 16%, stirring time 30 min and stirring temperature 200°C. Pharmacological activities of β-cyclodextrin encapsulation tea extract were determined. It was found that β-cyclodextrin encapsulation tea extract could enhance BMD, BMC and bone Ca, Zn and Cu contents. In addition, β-cyclodextrin encapsulation tea extract could still reduce blood Ca contents. These results indicated that β-cyclodextrin encapsulation tea extract was useful for improving bone quality in aged animals.
Huang, Wen-Ying; Lin, Yu-Ru; Ho, Ruei-Fen; Liu, Ho-Yen
This study investigates the effects of water solutions on the antioxidant content of green tea leaf extracts. Green teas prepared with tap water and distilled water were compared with respect to four antioxidant assays: total phenol content, reducing power, DMPD assay, and trolox equivalent antioxidant capacity assay. The results indicate that green tea prepared with distilled water exhibits higher antioxidant activity than that made with tap water. The high performance liquid chromatography showed that major constituents of green tea were found in higher concentrations in tea made with distilled water than in that made with tap water. This could be due to less calcium fixation in leaves and small water clusters. Water solutions composed of less mineralisation are more effective in promoting the quality of green tea leaf extracts. PMID:23997676
Stoeckle, Mark Y.; Gamble, Catherine C.; Kirpekar, Rohan; Young, Grace; Ahmed, Selena; Little, Damon P.
Appearance does not easily identify the dried plant fragments used to prepare teas to species. Here we test recovery of standard DNA barcodes for land plants from a large array of commercial tea products and analyze their performance in identifying tea constituents using existing databases. Most (90%) of 146 tea products yielded rbcL or matK barcodes using a standard protocol. Matching DNA identifications to listed ingredients was limited by incomplete databases for the two markers, shared or nearly identical barcodes among some species, and lack of standard common names for plant species. About 1/3 of herbal teas generated DNA identifications not found on labels. Broad scale adoption of plant DNA barcoding may require algorithms that place search results in context of standard plant names and character-based keys for distinguishing closely-related species. Demonstrating the importance of accessible plant barcoding, our findings indicate unlisted ingredients are common in herbal teas. PMID:22355561
Stoeckle, Mark Y; Gamble, Catherine C; Kirpekar, Rohan; Young, Grace; Ahmed, Selena; Little, Damon P
Appearance does not easily identify the dried plant fragments used to prepare teas to species. Here we test recovery of standard DNA barcodes for land plants from a large array of commercial tea products and analyze their performance in identifying tea constituents using existing databases. Most (90%) of 146 tea products yielded rbcL or matK barcodes using a standard protocol. Matching DNA identifications to listed ingredients was limited by incomplete databases for the two markers, shared or nearly identical barcodes among some species, and lack of standard common names for plant species. About 1/3 of herbal teas generated DNA identifications not found on labels. Broad scale adoption of plant DNA barcoding may require algorithms that place search results in context of standard plant names and character-based keys for distinguishing closely-related species. Demonstrating the importance of accessible plant barcoding, our findings indicate unlisted ingredients are common in herbal teas.
Einöther, Suzanne J; Martens, Vanessa E
Tea has historically been associated with mood and performance benefits, such as relaxation and concentration. This review summarizes the research on the acute effects of tea, and its ingredients theanine and caffeine, on attention and mood. Consistent with abundant research on the benefits of caffeine, the performance benefits of tea were identified in a number of studies, with particularly consistent evidence for improved attention. Tea consumption also consistently improved self-reported alertness and arousal, whereas effects on pleasure or relaxation were less consistent. In addition to the research on caffeine in real-life performance, 2 recent studies have provided a broader perspective on tea's effects on psychological function in that they showed beneficial effects in related areas such as work performance and creativity. These studies showed the validity of laboratory findings by supporting the idea that tea consumption has acute benefits on both mood and performance in real-life situations.
de Mejia, Elvira Gonzalez; Ramirez-Mares, Marco Vinicio; Puangpraphant, Sirima
Tea is one of the most widely consumed beverages worldwide. Several studies have suggested that catechins and theaflavins found in tea may reduce the risk of various types of cancers. Major advances have been made to understand the molecular events leading to cancer prevention; however, the evidence is not conclusive. Evidence from pre-clinical and clinical studies also suggests that persistent inflammation can progress to cancer. Several possible mechanisms of action may explain the cancer preventive aspects of tea components specifically anti-inflammatory effects. In regards to brain health, green tea catechins have been recognized as multifunctional compounds for neuroprotection with beneficial effects on vascular function and mental performance. Theanine, a unique amino acid in tea, enhances cognition in humans and has neuroprotective effects. Human interventional studies with well characterized tea products are needed.
Wang, Yu; Ho, Chi-Tang
Tea and coffee, the most popular beverages in the world, have been consumed for thousands of years for their alluring flavors and health benefits. Polyphenols, particularly flavonoids and phenolic acids, are of great abundance in tea and coffee and contribute a lot to their flavor and health properties. This paper reviews the polyphenol chemistry of tea and coffee, specifically their stability, and scavenging ability of reactive oxygen species (ROS) and reactive carbonyl species (RCS). During the manufacturing and brewing process, green tea and black tea polyphenols undergo epimerization and oxidation, respectively. Meanwhile, the lactonization and the polymerization of chlorogenic acid are the major causes for the degradation of polyphenols in coffee. Tea catechins, besides having antioxidant properties, have the novel characteristic of trapping reactive carbonyl species. The A ring of the catechins is the binding site for RCS trapping, whereas the B ring is the preferred site for antioxidation.
Chung, Fung-Lung; Schwartz, Joel; Herzog, Christopher R; Yang, Yang-Ming
The role of tea in protection against cancer has been supported by ample evidence from studies in cell culture and animal models. However, epidemiological studies have generated inconsistent results, some of which associated tea with reduced risk of cancer, whereas others found that tea lacks protective activity against certain human cancers. These results raise questions about the actual role of tea in human cancer that needs to be addressed. This article is intended to provide a better perspective on this controversy by summarizing the laboratory studies in animals and humans with emphasis on animal tumor bioassays on skin, lung, mammary glands and colon, and the molecular and cellular mechanisms affected by tea. Finally, a recent small pilot intervention study with green tea in smokers is presented.
The health benefits of green tea for a wide variety of ailments, including different types of cancer, heart disease, and liver disease, were reported. Many of these beneficial effects of green tea are related to its catechin, particularly (-)-epigallocatechin-3-gallate, content. There is evidence from in vitro and animal studies on the underlying mechanisms of green tea catechins and their biological actions. There are also human studies on using green tea catechins to treat metabolic syndrome, such as obesity, type II diabetes, and cardiovascular risk factors. Long-term consumption of tea catechins could be beneficial against high-fat diet-induced obesity and type II diabetes and could reduce the risk of coronary disease. Further research that conforms to international standards should be performed to monitor the pharmacological and clinical effects of green tea and to elucidate its mechanisms of action. PMID:20370896
Li, Yun-Shan; Kawasaki, Yuya; Tomita, Isao; Kawai, Kazuaki
Green tea ('Sencha'), made from the leaves of Camellia sinensis, is the most well-researched antioxidant beverage. The major source of its antioxidant activity is polyphenols, consisting mainly of catechins (flavan-3-ols). However, little is known about the physiological effects of green tea aroma, which lacks catechins. In the present study, we performed inhalation experiments with green tea aroma to evaluate its antioxidant activity in mice. As a result, the urinary 8-hydroxydeoxyguanosine levels were significantly decreased in comparison with those of the non-treated group, and the serum antioxidant capacity was significantly increased by the inhalation administration of green tea aroma. Furthermore, the increase in the urinary 8-hydroxydeoxyguanosine levels due to whole-body X-ray irradiation was significantly suppressed by the inhalation of green tea aroma. This is the first study to show the antioxidant activity of green tea aroma in vivo.
Mary Torsello; Toni McLellan
The goals of hazard tree management programs are to maximize public safety and maintain a healthy sustainable tree resource. Although hazard tree management frequently targets removal of trees or parts of trees that attract wildlife, it can take into account a diversity of tree values. With just a little extra planning, hazard tree management can be highly beneficial...
AFRL-RH-WP-TR-2015-0076 Performance Assessment of Communication Enhancement Devices: TEA HI Threat Headset Hilary L. Gallagher...of Communication Enhancement Devices: TEA HI Threat Headset 5a. CONTRACT NUMBER FA8650-14-D-6501 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER...technology in military applications. Objective performance data provided an assessment of the performance of these devices. The TEA HI Threat headset
Green Tea for Prostate Cancer Prevention PRINCIPAL INVESTIGATOR: Hasan Mukhtar, Ph.D. CONTRACTING ORGANIZATION: University of...Nanoformulated Green Tea for Prostate Cancer Prevention 5b. GRANT NUMBER W81XWH-10-1-0245 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Principal...chemopreventive properties green tea has shown promise in preclinical, epidemiological and initial clinical studies. However, absolute clinical success
Goenka, Puneet; Sarawgi, Aditi; Karun, Vinayak; Nigam, Anant G; Dutta, Samir; Marwah, Nikhil
Tea is one of the most commonly consumed beverages with bioactive compounds like polyphenols-flavonoids-catechins, which are thought to be responsible for the health benefits that have traditionally been attributed to the tea. These compounds have multi-dimensional effects such as antibacterial action, inhibitory action on the bacterial and salivary amylase and inhibition of acid production. This article outlines the possible role of these compounds coupled with the presence of high fluoride content in tea to exhibit an anticariogenic effect.
This project aimed to define the effects of green tea polyphenols (GTPs) on cell signaling pathways and on mammary tumorigenesis in MMTV/c-neu...transgenic mice. The studies showed that the major polyphenol in green tea , EGCG, did not impair erbB-2 tyrosine phosphorylation or EGF-dependent activation...of MAP kinase in transformed or untransformed MCFlOA cells, and that orally administered green tea or GTPs did not inhibit mammary tumorigenesis
Butler, Ricky W.; Boerschlein, David P.
Fault-Tree Compiler (FTC) program, is software tool used to calculate probability of top event in fault tree. Gates of five different types allowed in fault tree: AND, OR, EXCLUSIVE OR, INVERT, and M OF N. High-level input language easy to understand and use. In addition, program supports hierarchical fault-tree definition feature, which simplifies tree-description process and reduces execution time. Set of programs created forming basis for reliability-analysis workstation: SURE, ASSIST, PAWS/STEM, and FTC fault-tree tool (LAR-14586). Written in PASCAL, ANSI-compliant C language, and FORTRAN 77. Other versions available upon request.
Fisler, Marie; Lecointre, Guillaume
The aim of this study is to explore whether matrices and MP trees used to produce systematic categories of organisms could be useful to produce categories of ideas in history of science. We study the history of the use of trees in systematics to represent the diversity of life from 1766 to 1991. We apply to those ideas a method inspired from coding homologous parts of organisms. We discretize conceptual parts of ideas, writings and drawings about trees contained in 41 main writings; we detect shared parts among authors and code them into a 91-characters matrix and use a tree representation to show who shares what with whom. In other words, we propose a hierarchical representation of the shared ideas about trees among authors: this produces a “tree of trees.” Then, we categorize schools of tree-representations. Classical schools like “cladists” and “pheneticists” are recovered but others are not: “gradists” are separated into two blocks, one of them being called here “grade theoreticians.” We propose new interesting categories like the “buffonian school,” the “metaphoricians,” and those using “strictly genealogical classifications.” We consider that networks are not useful to represent shared ideas at the present step of the study. A cladogram is made for showing who is sharing what with whom, but also heterobathmy and homoplasy of characters. The present cladogram is not modelling processes of transmission of ideas about trees, and here it is mostly used to test for proximity of ideas of the same age and for categorization. PMID:23950877
Catephen (Kora Corporation Ltd) is a herbal medicinal product consisting predominantly of catechins (sinecatechins) extracted from Camellia sinensis (L.) O. Kuntze folium (green tea leaf) formulated as a topical preparation for the treatment of external genital and perianal warts (condylomata acuminata).(1) Marketing authorisation for an ointment containing 0.1g of green tea extract per gram (10%) was granted by the Medicines and Healthcare products Regulatory Agency (MHRA) under the mutual recognition procedure in February 2015.(2) Here, we consider the evidence for Catephen ointment in the management of external genital and perianal warts and its place within current management strategies. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.
Seyani, Chitsa; Green, Peregrine; Daniel, Lisa; Pegden, Amanda
We present an unusual cause of respiratory arrest resulting from sole ingestion of home-brewed opium tea. A 64-year-old woman was found unresponsive and in respiratory arrest by a first responder. There were no obvious signs of regular recreational drug use. On presentation to the local district general hospital, the patient was in extremis, with severe physiological and biochemical derangements. A naloxone infusion was commenced and she later made a good recovery. It was subsequently discovered that she had brewed opium tea from opium buds she had picked from a nearby commercial poppy farm, a practice she had learnt while in Afghanistan. © BMJ Publishing Group Ltd (unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.
Song, Yoon Ju; Kristal, Alan R; Wicklund, Kristine G; Cushing-Haugen, Kara L; Rossing, Mary Anne
Associations of coffee, tea, and other caffeinated beverages with ovarian cancer risk remain uncertain. In a population-based study in Washington State, 781 women with epithelial ovarian cancer diagnosed in 2002 to 2005 and 1,263 controls completed self-administered questionnaires detailing consumption of caffeinated and noncaffeinated coffee, teas, and colas and in-person interviews regarding reproductive and hormonal exposures. We assessed risk associated with coffee, tea, and cola drinking and with total caffeine consumption using logistic regression to calculate odds ratios and 95% confidence intervals. Neither caffeinated nor decaffeinated coffees were associated with ovarian cancer risk; also, we observed no association of total caffeine with risk using a combined index that summed intake from coffee, tea, and carbonated soft drinks. Among teas, neither herbal/decaffeinated nor black teas were associated with risk; however, women who reported drinking >or=1 cup/d of green tea had a 54% reduction in risk (P trend = 0.01). Associations of green tea with risk were similar when invasive and borderline cases were considered separately and when Asian women were excluded from analysis. Green tea, which is commonly consumed in countries with low ovarian cancer incidence, should be further investigated for its cancer prevention properties.
Marzuki, A.; Suryanti, V.; Virgynia, A.
This paper reports the analysis of UV-VIS-NIR absorption spectra of different concentrations of green tea (Camellia sinensis) leaf extract in two different solvent systems (chloroform and ethyl acetate). In those solvents, two different peaks characterizing green tea are observed at different wavelengths, namely 296 nm and 329 nm (extracted in chloroform) and 391 nm and 534 nm (extracted in ethyl acetate). We then investigated the absorption spectra change as function of green tea concentration in both solvents. We found that light absorption increases linearly with the increase of green tea concentration. Different wavelengths, however, respond this change differently. However, the way it changes is wavelength dependence.
Siddiqui, Imtiaz A; Adhami, Vaqar M; Saleem, Mohammad; Mukhtar, Hasan
Tea, next to water, is the most widely consumed beverage in the world. Depending upon the level of fermentation, tea can be categorized into three types: green (unfermented), oolong (partially fermented), and black (highly to fully fermented). In general, green tea has been found to be superior to black and oolong tea in terms of antioxidant and health promoting benefits owing to the higher content of (-)-epigallocatechin-3-gallate. Tea polyphenols comprise about one-third of the weight of the dried leaf, and they exhibit biochemical and pharmacological activities including antioxidant activities, inhibition of cell proliferation, induction of apoptosis, cell cycle arrest and modulation of carcinogen metabolism. Several studies demonstrate that most tea polyphenols exert their effects by scavenging reactive oxygen species (ROS) since excessive production of ROS has been implicated in the development of a variety of ailments including cancer of the prostate gland (CaP). Using cell culture and animal model systems, molecular targets for these remarkable beneficial effects of green tea drinking on CaP prevention and therapy have been defined. Geographical and case-control studies are showing that green tea drinking could afford CaP chemopreventive effects in human population. In this review we attempt to summarize the experimental as well as the epidemiological basis for the possible role of tea and its polyphenols for chemoprevention and chemotherapy of CaP.
Chatterjee, Anirban; Saluja, Mini; Agarwal, Gunjan; Alam, Mahtab
Green tea is particularly rich in health-promoting flavonoids (which account for 30% of the dry weight of a leaf), including catechins and their derivatives. The most abundant catechin in green tea is epigallocatechin-3-gallate, which is thought to play a pivotal role in the green tea's anticancer and antioxidant effects. Catechins should be considered right alongside of the better-known antioxidants like vitamins E and C as potent free radical scavengers and health-supportive for this reason. It has been suggested that green tea also promotes periodontal health by reducing inflammation, preventing bone resorption and limiting the growth of certain bacteria associated with periodontal diseases. PMID:23055579
Islam, Mohammed A
Recently, there is a growing interest in the cardiovascular beneficial effects of green tea. Epidemiological and clinical studies have suggested that consumption of green tea is inversely associated with the risk of developing cardiovascular diseases. Catechins, the major flavonoid constituents of green tea, exert cardioprotective effects through diverse mechanisms that include reversal of endothelial dysfunctions, decreasing inflammatory biomarkers, and providing antioxidant, antiplatelet and antiproliferative effects. Moreover, dietary consumption of green tea catechins has beneficial effects on blood pressure and lipid parameters. This review will focus on discussing the latest research on the cardioprotective effects of green tea catechins and their underlying molecular mechanisms. Several recent patents pertinent to green tea and cardiovascular health will also be discussed. It is noteworthy that clinical studies involving green tea are fraught with multiple complexity and confounding factors. Therefore, a rigorous assessment of the effects of green tea catechins in well-controlled human trials will be required for better understanding of the effects of green tea in cardiovascular health.
Watanabe, S; Haba, R; Terashima, K; Arai, Y; Miura, T; Chiba, H; Takamatsu, K
Antioxidative activity of isoflavones has not been shown in humans. Newly-developed isoflavone-rich soya hypocotyl tea contains about 12 mg isoflavones per liter. 15 tea drinkers and 23 control young female students were randomly selected from volunteers, and underwent physical examination, blood chemistry and urinary analysis before and after one month of tea drinking. A three-day dietary record was taken before each physical examination. The tea drinkers showed a lower level of phosphatidylcholine hydroperoxide (PCOOH) and phosphatidyl-ethanolamine hydroperoxide (PEOOH) in the red blood cells and a significant reduction of 8-hydroxydeoxyguanine (8ohdG) in the urine compared to the controls.
Polyphenolic compounds in green tea have been implicated in the prevention of cancer, but their effects on cell signalling pathways are unknown. The...cancers in mice. Using the EGF dependent growth of MCF1OA epithelial cells as a model, we found that the major polyphenol in green tea , EGCG, inhibited...inhibitory effect of green tea or tea polyphenols on c-neu induced mammary tumorigenesis in mice, suggesting that c-neu signals in a way that resists the effects of such compounds.
Mahdavi, Reza; Lotfi Yagin, Neda; Liebman, Michael; Nikniaz, Zeinab
Because of the postulated role of increased dietary oxalate intake in calcium oxalate stone formation, the effect of different brewing times on soluble oxalate contents of loose-packed black tea and tea bags was studied. The oxalate content of 25 different samples of loose-packed black teas after brewing at 5, 10, 15, 30, and 60 min and of ten brands of tea bags after infusion for 1, 2, 3, 4, and 5 min was measured by enzymatic assay. The oxalate concentration resulting from different brewing times ranged from 4.3 to 6.2 mg/240 ml for loose-packed black teas and from 2.7 to 4.8 mg/240 ml for tea bags. There was a stepwise increase in oxalate concentration associated with increased brewing times.
Dutta, Jintu; Handique, Pratap J; Thakur, Debajit
In the present study, 217 rhizobacterial isolates were obtained from six different tea estates of Assam, India and subjected to preliminary in vitro plant growth promotion (PGP) screening for indole acetic acid (IAA) production, phosphate solubilization, siderophore production and ammonia production. Fifty isolates showed all the PGP traits and five isolates did not exhibit any PGP traits. These 50 potential isolates were further analyzed for quantitative estimation of the PGP traits along with the aminocyclopropane-1-carboxylate (ACC) deaminase, protease and cellulose production. After several rounds of screening, four rhizobacteria were selected based on their maximum ability to produce in vitro PGP traits and their partial 16S rRNA gene sequence analysis revealed that they belong to Enterobacter lignolyticus strain TG1, Burkholderia sp. stain TT6, Bacillus pseudomycoides strain SN29 and Pseudomonas aeruginosa strain KH45. To evaluate the efficacy of these four rhizobacteria as plant growth promoters, three different commercially important tea clones TV1, TV19, and TV20 plants were inoculated with these rhizobacteria in greenhouse condition and compared to the uninoculated control plants. Though, all the rhizobacterial treatments showed an increase in plant growth compared to control but the multivariate PCA analysis confirmed more growth promotion by TG1 and SN29 strains than the other treatments in all three clones. To validate this result, the fold change analysis was performed and it revealed that the tea clone TV19 plants inoculated with the E. lignolyticus strain TG1 showed maximum root biomass production with an increase in 4.3-fold, shoot biomass with increase in 3.1-fold, root length by 2.2-fold and shoot length by 1.6-fold. Moreover, two way ANOVA analysis also revealed that rhizobacterial treatment in different tea clones showed the significant increase (P < 0.05) in growth promotion compared to the control. Thus, this study indicates that the