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a preliminary investigation of anticholinesterase activity of some iranian medicinal plants commonly used in traditional medicine.the aim of this study was to evaluate acetylcholinesterase inhibitory activity of some commonly used herbal medicine in iran to introduce a new source for management of alzheimer's disease. a total of 18 aqueous-methanolic extract (1:1; v/v) from the following plants: brassica alba, brassica nigra, camellia sinensis, cinchona officinalis, citrus aurantifolia, citrus x aurantium, ferula assafoetida, humulus lupulus, juglans regia, juniperus sabina, myristica fragrans, pelargonium graveolens, pist ...201424401532
effects of plant extracts on the reversal of glucose-induced impairment of stress-resistance in caenorhabditis elegans.enhanced blood glucose levels are a hallmark of diabetes and are associated with diabetic complications and a reduction of lifespan. in order to search for plant extracts that display preventive activities in such a scenario, we tested 16 extracts used in human nutrition for their survival enhancing activities in the nematode caenorhabditis elegans. nematodes were exposed for 48 h to 10 mm glucose in the absence or presence of 0.1% extract. thereafter, survival was measured at 37 °c. extracts ma ...201424390728
association of tea consumption and the risk of oral cancer: a meta-analysis.epidemiological studies evaluating the association of tea consumption and the risk of oral cancer risk have produced inconsistent results. thus, we conducted a meta-analysis to assess the relationship between tea consumption and oral cancer risk.201424389399
extraction of al, cu, fe, mn, ni and zn--polyphenol complexes from black tea infusions by amberlite resins.metals can be present in tea infusion as ions or as complexes with endogenous bioligands naturally occurring in tea, especially with polyphenols. their chemical form, i.e. free or metal complexes, can affect their actual bioavailability, gastrointestinal absorption and possible toxicity.201424374716
white tea as a promising antioxidant medium additive for sperm storage at room temperature: a comparative study with green tea.storage of sperm under refrigeration reduces its viability, due to oxidative unbalance. unfermented teas present high levels of catechin derivatives, known to reduce oxidative stress. this study investigated the effect of white tea (wtea) on epididymal spermatozoa survival at room temperature (rt), using green tea (gtea) for comparative purposes. the chemical profiles of wtea and gtea aqueous extracts were evaluated by (1)h nmr. (-)-epigallocatechin-3-gallate was the most abundant catechin, bein ...201424372402
exogenous abscisic acid significantly affects proteome in tea plant (camellia sinensis) exposed to drought stress.tea [camellia sinensis (l.) o. kuntze] is an important economic crop, and drought is the most important abiotic stress affecting yield and quality. abscisic acid (aba) is an important phytohormone responsible for activating drought resistance. increased understanding of aba effects on tea plant under drought stress is essential to develop drought-tolerant tea genotypes, along with crop management practices that can mitigate drought stress. the objective of the present investigation is evaluation ...201427076915
green tea extract induces the resistance of caenorhabditis elegans against oxidative stress.epidemiological studies on the effects of green tea consumption (camellia sinensis) have demonstrated a reduction for the risk of age-related diseases. the investigation of the in vivo and in vitro antioxidant properties of an aqueous extract of green tea (gte) was the aim of the current study. 2,2-diphenyl-1-picrylhydrazyl (dpph(•)) and superoxide anion radical (o₂(•-)) assays were used to estimate the gte antioxidant activity. to investigate the protective effects of gte against oxidative stre ...201426784668
maillard reaction of pidan white as inhibited by chinese black tea extract (camellia sinensis) in the pickling solution.changes in maillard reaction of pidan white were monitored with a294, fluorescence intensity, and browning intensity during pickling in the absence and presence of chinese black tea extract (camellia sinensis) at levels of 2% and 5% together with 0.2% zncl2 or 0.2% cacl2 up to 3 wk, followed by ageing for another 3 wk. browning intensity and a294 of pidan white increased with increasing pickling/ageing, while fluorescence intensity decreased during ageing (p<0.05), irrespective of treatments. at ...201426761277
varietal identification of tea (camellia sinensis) using nanofluidic array of single nucleotide polymorphism (snp) markers.apart from water, tea is the world's most widely consumed beverage. tea is produced in more than 50 countries with an annual production of approximately 4.7 million tons. the market segment for specialty tea has been expanding rapidly owing to increased demand, resulting in higher revenues and profits for tea growers and the industry. accurate varietal identification is critically important to ensure traceability and authentication of premium tea products, which in turn contribute to on-farm con ...201426504544
coffee and beverages are the major contributors to polyphenol consumption from food and beverages in japanese middle-aged women.food and beverages rich in polyphenols have been shown to reduce the risk of non-communicable diseases. the present study estimated polyphenol levels and consumption from food and beverages in japanese women. randomly recruited housewives living in the area around tokyo (n 109; aged 21-56 years; group 1) recorded all beverages and foods they ingested for 7 d, and the total polyphenol (tp) consumption was estimated based on the tp content of each item measured with a modified folin-ciocalteu meth ...201426101616
effect of white tea (camellia sinensis (l.)) extract in the glycolytic profile of sertoli cell.many health benefits have been attributed to tea (camellia sinensis (l.)), and tea infusions are used as dietary agent and included in food supplements. herein, we report the effect of a white tea (wtea) extract in sertoli cell (sc) metabolism. the sc is responsible for the nutritional support of the developing germ cells.201424363139
evaluation of the protective effect of ilex paraguariensis and camellia sinensis extracts on the prevention of oxidative damage caused by ultraviolet radiation.we evaluated the effects green and mate teas on oxidative and dna damages in rats exposed to ultraviolet radiation. were utilized 70 adult male wistar rats that received daily oral or topic green or mate tea treatment during exposed to radiation by seven days. after, animals were killed by decapitation. thiobarbituric acid-reactive species levels, protein oxidative damage were evaluated in skin and dna damage in blood. our results show that the rats exposed to ultraviolet radiation presented dna ...201424361697
a comparative study of the antioxidant scavenging activity of green tea, black tea and coffee extracts: a kinetic approach.the antioxidant activities of three beverages, coffee, black tea and green tea, along with their major components, were investigated in terms of their reaction with the stable radical 2,2'-diphenyl-2-picrylhydrazyl (dpph). we used a kinetic approach in parallel with quantification methods based on a fixed end-point to determine the scavenging efficiency of compounds abundant in these beverages during their reaction with dpph using a stopped-flow spectrophotometer-based method. ascorbic acid, (+) ...201424360473
development of liquid chromatography-tandem mass spectrometry method for analysis of polyphenolic compounds in liquid samples of grape juice, green tea and coffee.a simple and fast method for the analysis of a wide range of polyphenolic compounds in juice, tea, and coffee samples was developed using liquid chromatography-tandem mass spectrometry (lc-ms/ms). the method was based on a simple sample preparation "dilute and shoot" approach, and lc-ms/ms quantification using genistein-d4 as an internal standard. the performance of six different syringeless filter devices was tested for sample preparation. the method was evaluated for recoveries of polyphenols ...201424360423
influence of cytokinins in combination with ga₃ on shoot multiplication and elongation of tea clone iran 100 (camellia sinensis (l.) o. kuntze).the use of in vitro culture has been accepted as an efficient technique for clonal propagation of many woody plants. in the present research, we report the results of a number of experiments aimed at optimizing micropropagation protocol for tea (camellia sinensis (l.) o. kuntze) (clone iran 100) using nodal segments as the explant. the effect of different combinations and concentrations of plant growth regulators (pgr) (bap, tdz, ga₃) on shoot multiplication and elongation was assessed. the infl ...201424605069
determination of quality constituents in the young leaves of albino tea cultivars.albino tea has received increased attention due to its brisk flavour. to identify changes in the key chemical constituents conveying important qualities to albino tea, the metabolite profiles of four albino cultivars and one green tea cultivar were analysed. compared to the green tea control, significantly decreased contents of chlorophyll (chl) (p<0.01), total carotenoids (p<0.05), caffeine (p<0.01), and total catechins (p<0.05) were found in albino tea leaves with a few exceptions, whereas inc ...201424594160
catechin concentrates of garden tea leaves (camellia sinensis l.): extraction/isolation and evaluation of chemical composition.solid-liquid (sle) and liquid-liquid (lle) extraction techniques were applied to extract catechins and caffeine from quick mechanically expelled tea leaf juice (qmetlj) and freeze-dried (fd)-qmetlj of camellia sinensis l. the concentrates obtained were analyzed for total polyphenol content and antioxidant activity (dpph(•) inhibition, frap and phosphomolybdenum assay). catechins were identified and quantified using hplc.201424585505
effects of single dose and regular intake of green tea (camellia sinensis) on dna damage, dna repair, and heme oxygenase-1 expression in a randomized controlled human supplementation study.regular intake of green tea (camellia sinensis) lowers dna damage in humans, but molecular mechanisms of genoprotection are not clear. protection could be via direct antioxidant effects of tea catechins, but, paradoxically, catechins have pro-oxidant activity in vitro, and it is hypothesized that mechanisms relate to redox-sensitive cytoprotective adaptations. we investigated this hypothesis, focusing particularly on effects on the dna repair enzyme human oxoguanine glycosylase 1 (hogg1), and he ...201424585444
dentin biomodification potential depends on polyphenol source.although proanthocyanidins (pacs) modify dentin, the effectiveness of different pac sources and the correlation with their specific chemical composition are still unknown. this study describes the chemical profiling of natural pac-rich extracts from 7 plants using ultra high pressure/performance liquid chromatography (uhplc) to determine the overall composition of these extracts and, in parallel, comprehensively evaluate their effect on dentin properties. the total polyphenol content of the extr ...201424574140
green tea (camellia sinensis) extract inhibits both the metastasis and osteolytic components of mammary cancer 4t1 lesions in mice.green tea (camellia sinensis, cs), a kind of chinese tea commonly consumed as a healthy beverage, has been demonstrated to have various biological activities, including antioxidation, antiobesity and anticancer. our study aims to investigate the antitumor, antimetastasis and antiosteolytic effects of cs aqueous extract both in vitro and in vivo using metastasis-specific mouse mammary carcinoma 4t1 cells. our results showed that treatment of 4t1 cells with cs aqueous extract resulted in significa ...201424561153
tea and coffee consumption and risk of esophageal cancer: the european prospective investigation into cancer and nutrition study.epidemiological data regarding tea and coffee consumption and risk of esophageal cancer (ec) is still inconclusive. we examined the association of tea and coffee consumption with ec risk among 442,143 men and women without cancer at baseline from 9 countries of the european prospective investigation into cancer and nutrition. tea and coffee intakes were recorded using country-specific validated dietary questionnaires. cox regression models were used to analyze the relationships between tea and c ...201424535727
multiresidue method for the fast determination of pesticides in nutraceutical products (camellia sinensis) by gc coupled to triple quadrupole ms.a method based on quechers (quick, easy, cheap, effective, rugged, and safe) has been developed and validated for the determination and quantification of more than 140 pesticides in nutraceutical products obtained from green tea (camellia sinensis). extraction was performed with acidified acetonitrile (acetic acid 1%, v/v) and a clean-up step using primary secondary amine (50 mg), graphitized black carbon (100 mg) and magnesium sulfate (200 mg) was needed. pesticide determination was achieved ut ...201424532456
tea, coffee, and milk consumption and colorectal cancer risk.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.201424531002
tea consumption and prostate cancer: an updated meta-analysis.tea is supposed to have chemopreventive effect against various cancers. however, the protective role of tea in prostate cancer is still controversial. the aim of this study is to elucidate the association between tea consumption and prostate cancer risk by meta-analysis.201424528523
effects of hemp (cannabis sativa l.) seed oil press-cake and decaffeinated green tea leaves (camellia sinensis) on functional characteristics of gluten-free crackers.a mixture, simplex centroid, 2 components experimental design was used to evaluate the addition of hemp seed oil press-cake and decaffeinated green tea leaves, as functional ingredients to assess nutritional characteristics and antioxidant properties of gluten-free crackers. all samples with added hemp flour had much better nutritional qualities than the brown rice flour crackers in terms of higher protein, crude fibers, minerals, and essential fatty acids content. likewise, all samples with add ...201424527987
pharmacokinetics and biotransformation of tea polyphenols.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 attra ...201424527703
interaction of some commercial teas with some carbohydrate metabolizing enzymes linked with type-2 diabetes: a dietary intervention in the prevention of type-2 diabetes.this study is aimed at assessing the inhibitory effect of teas on key enzymes (α-amylase and α-glucosidase) linked with type-2 diabetes and their antioxidant properties. four samples of three brands were used; infusions of green tea (gt), 2 brands of black tea (bt), and a formulated herbal preparation for diabetes (adt) (white tea, radix puerariae, radix ophiopogonis, hawthorn berry, chinese yam, and fragrant solomon seal rhizome) were prepared and subsequently analyzed for their total phenol, a ...201424527218
caffeine in tea camellia sinensis--content, absorption, benefits and risks of consumption.therapeutic properties of tea camellia sinensis are of particular interest since it has been consumed for ages and was always regarded as safe beverage. tea is most popular beverage in the world because of its attractive aroma, exceptional taste, health promoting and pharmaceutical potential. current results showed that antioxidative, antibacterial and other health effects are attributed to its caffeine content and caffeine - polyphenols interactions. an overview is given on caffeine content in ...201424522465
quantification of antioxidants by using chlorpromazine hydrochloride: application of the method to food and medicinal plant samples.chlorpromazine hydrochloride (cph) (3-(2-chloro-phenothiazine-10-yl)-propyl] dimethylamine hydrochloride) has been the subject of a large number of studies employing a broad spectrum of oxidants, and chosen to examine the course of electron transfer reactions. we report on a method to determine the antioxidant activity of some food and medicinal plants using the oxidation of cph by chromium(vi) to form a stable cph radical in the 1:1 orthophosphoric acid-ethyl alcohol (opa-etoh) medium. the pink ...201424521912
assessment of exogenous pigmentation in colourless elastic ligatures.the aim of this study was to evaluate colour alteration of transparent elastic ligatures submitted to exogenous pigmentation.201424521746
diet patterns and risk of squamous cell oesophageal carcinoma: a case-control study in uruguay.oesophageal cancer presents high incidence rates in the so-called brazilian-uruguayan belt.201424761898
induction of apoptosis and cytotoxic activities of iranian orthodox black tea extract (bte) using in vitro models.plant-derivate therapeutic agents can perform cancer chemotherapeutic activity through triggering apoptotic cell death. our aim was to investigate the cytotoxic effects, induction of apoptosis, and the mechanism of cell death of iranian orthodox black tea extracts (btes) and hydro methanolic purified fractions (40, 60, 80 and 100%) in kb cells (oral squamous cell carcinoma).201424754009
crystal structures of β-primeverosidase in complex with disaccharide amidine inhibitors.β-primeverosidase (pd) is a disaccharide-specific β-glycosidase in tea leaves. this enzyme is involved in aroma formation during the manufacturing process of oolong tea and black tea. pd hydrolyzes β-primeveroside (6-o-β-d-xylopyranosyl-β-d-glucopyranoside) at the β-glycosidic bond of primeverose to aglycone, and releases aromatic alcoholic volatiles of aglycones. pd only accepts primeverose as the glycone substrate, but broadly accepts various aglycones, including 2-phenylethanol, benzyl alcoho ...201424753293
coffee, alcohol and other beverages in relation to cirrhosis mortality: the singapore chinese health study.limited experimental and epidemiologic data suggest that coffee may reduce hepatic damage in chronic liver disease. the association between consumption of coffee and other beverages and risk of cirrhosis mortality was evaluated in the singapore chinese health study. this is a prospective population-based cohort of 63,275 middle-aged and older chinese subjects who provided data on diet, lifestyle, and medical histories through in-person interviews using a structured questionnaire at enrollment be ...201424753005
colour stainability of indirect cad-cam processed composites vs. conventionally laboratory processed composites after immersion in staining solutions.the aim of this study was to determine, by using a spectrophotometer device, the colour stainability of two indirect cad/cam processed composites in comparison with two conventionally laboratory-processed composites after being immersed 4 weeks in staining solutions such as coffee, black tea and red wine, using distilled water as control group.201424746713
the characterization of caffeine and nine individual catechins in the leaves of green tea (camellia sinensis l.) by near-infrared reflectance spectroscopy.near-infrared reflectance spectroscopy (nirs) was used to determine the contents of caffeine and nine individual catechins in tea leaves. a total of 665 samples were scanned by nirs, and also by high performance liquid chromatography coupled to a diode array detector to determine the contents of caffeine and nine individual catechins. the calibration models for caffeine, egc, c, egcg, ec, ecg, and total catechins had high r(2) (more than 0.90) and rsp (the ratio of standard deviation of referenc ...201424731354
the use of green tea (<i>camellia sinensis</i>) as a phytogenic substance in poultry diets.this review examined the use of green tea (camellia sinensis) in the diets of poultry. research findings were obtained from various recent studies, where much attention was focused on the role of green tea in the promotion of both animal and human health. the review involved some of the currently available information about green tea, pertaining to its chemical composition, anticoccidial and antimicrobial effect, effect on broiler and layer performance and on blood and egg yolk constituents. to ...201428235287
aroma changes of black tea prepared from methyl jasmonate treated tea plants.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. ...201424711352
the red spider mite, oligonychus coffeae (acari: tetranychidae): its status, biology, ecology and management in tea plantations.oligonychus coffeae nietner (acari: tetranychidae), the red spider mite (rsm), is a major pest of tea (camellia sinensis) in most tea-producing countries. nymphs and adults of rsm lacerate cells, producing minute characteristic reddish brown marks on the upper surface of mature leaves, which turn red in severe cases of infestation, resulting in crop loss. the pest is present on tea all the year round, although numbers vary depending on season. their number increases as the weather warms up and d ...201424705870
interactions among chemical components of cocoa tea (camellia ptilophylla chang), a naturally low caffeine-containing tea species.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 ...201424699984
application of derivative and derivative ratio spectrophotometry to simultaneous trace determination of rhodamine b and rhodamine 6g after dispersive liquid-liquid microextraction.two novel methods, first derivative spectrophotometric method ((1)d) and first derivative ratio spectrophotometric method ((1)dr), have been developed for the simultaneous trace determination of rhodamine b (rhb) and rhodamine 6g (rh6g) in food samples after dispersive liquid-liquid microextraction (dllme). the combination of derivative spectrophotometric techniques and dllme procedure endows the presented methods with enhanced sensitivity and selectivity. under optimum conditions, the linear ca ...201424691361
construction of a ssr-based genetic map and identification of qtls for catechins content in tea plant (camellia sinensis).catechins are the most important bioactive compounds in tea, and have been demonstrated to possess a wide variety of pharmacological activities. to characterize quantitative trait loci (qtls) for catechins content in the tender shoots of tea plant, we constructed a moderately saturated genetic map using 406 simple sequence repeat (ssr) markers, based on a pseudo-testcross population of 183 individuals derived from an intraspecific cross of two camellia sinensis varieties with diverse catechins c ...201424676054
the effect of green tea on blood pressure and lipid profile: a systematic review and meta-analysis of randomized clinical trials.many different dietary supplements are currently marketed for the management of hypertension, but the evidence for effectiveness is mixed. the aim of this systematic review was to evaluate the evidence for or against the effectiveness of green tea (camellia sinensis) on blood pressure and lipid parameters.201424675010
rapid and sustained systemic circulation of conjugated gut microbial catabolites after single-dose black tea extract consumption.gut microbial catabolites of black tea polyphenols (btps) have been proposed to exert beneficial cardiovascular bioactivity. this hypothesis is difficult to verify because the conjugation patterns and pharmacokinetics of these catabolites are largely unknown. the objective of our study was to identify, quantify, and assess the pharmacokinetics of conjugated btp metabolites in plasma of healthy humans by means of an a priori untargeted lc-ms-based metabolomics approach. in a randomized, open, pla ...201424673575
differential expression of micrornas in dormant bud of tea [camellia sinensis (l.) o. kuntze].expression analysis of mirnas and understanding their target genes function in dormant tea bud might be used to identify molecular network panel and novel approaches for modulating dormancy in tea. tea [camellia sinensis (l) o. kuntze, theaceae] is an important commercial beverage crop manufactured from the apical bud and two leaves immediately below the bud. the yield and quality of tea depend on the vegetative growth of shoots and bud dormancy. the dormancy of bud is being regulated by many fa ...201424658841
the resonance rayleigh light scattering spectral investigation on the interaction of dna with camellia sinensis in the presence of cpc and its analytical application.a novel method with high sensitivity was designed for the determination of trace nucleic acids by using cationic surfactant cetylpyridinium chloride (cpc) and camellia sinensis (cs) as resonance rayleigh light scattering (rls) probes. it was found dna could combine with cs and cpc in tris-hcl buffer (ph=7.4). under optimum conditions, the rls intensity of dna can be enhanced by cpc-cs obviously at 294nm, and the enhanced rls intensity was directly proportional to dna concentration in the range f ...201424637271
tea consumption and the risk of five major cancers: a dose-response meta-analysis of prospective studies.we conducted a dose-response meta-analysis of prospective studies to summarize evidence of the association between tea consumption and the risk of breast, colorectal, liver, prostate, and stomach cancer.201424636229
biosynthesis of catechin components is differentially regulated in dark-treated tea (camellia sinensis l.).tea (camellia sinensis l.) is a crop with both commercial and medicinal value with remarkably high polyphenol content in the form of catechins. to understand the molecular regulation of catechin biosynthesis in tea, we treated the tea plants with darkness. we used qrt-pcr to validate the expression of genes involved in catechin biosynthesis. it indicated that dark treatment displayed different effects on the genes participating in tea flavonoid (fl) pathway. the early genes of fl biosynthesis pa ...201424632491
black tea extract and its thearubigins relieve the sildenafil-induced delayed gut motility in mice: a possible role of nitric oxide.in this study we hypothesize that a standardized black tea aqueous extract (bte) and thearubigins, its main polyphenolic pigments, will improve sildenafil-induced delay in gastric emptying (ge) and small intestinal transit (sit) in mice. twenty groups of mice (n = 8) were given a phenol red meal, and three sets of experiments were performed. in the first and second sets, effects of different concentrations of bte, thearubigins (trs), and sildenafil (sld), alone and in combinations, on ge and sit ...201424895242
metabolic variation and antioxidant potential of malus prunifolia (wild apple) compared with high flavon-3-ol containing fruits (apple, grapes) and beverage (black tea).secondary metabolic variation of wild apple (malus prunifolia) was compared with fruits that contained high flavan-3-ol like grapes (gr), apple (app) and the beverage, black tea (bt). the polyphenol contents in wild apple was higher than in gr and app but less than bt. the identified phenolic acids (gallic, protocatechuic, chlorogenic, p-coumaric and ferulic acids) and flavonoids (quercetin and myricetin) indicate that wild apple was higher than that of app. among all the samples, bt had highest ...201424912694
high-quality green tea leaf production by artificial cultivation under growth chamber conditions considering amino acids profile.the current study focused on the tea plant (camellia sinensis) as a target for artificial cultivation because of the variation in its components in response to light conditions. we analyzed its sensory quality by multi-marker profiling using multicomponent data based on metabolomics to optimize the conditions of light and the environment during cultivation. from the analysis of high-quality tea samples ranked in a tea contest, the ranking predictive model was created by the partial least squares ...201424915994
identification of novel homologous series of polyhydroxylated theasinensins and theanaphthoquinones in the sii fraction of black tea thearubigins using esi/hplc tandem mass spectrometry.thearubigins are the most abundant phenolic pigments found in black tea, produced by enzymatic oxidation of green tea flavan-3-ols in tea fermentation of until recently unknown composition. in this study electrospray ionization tandem lc-ms(n) experiments have been applied for the characterization of crude thearubigins isolated from black tea not exceeding 1000 da. the aim of this study is to confirm the oxidative cascade hypothesis of tea fermentation. the data revealed the presence of two nove ...201425263270
organochlorine pesticides and pyrethroids in chinese tea by screening and confirmatory detection using gc-nci-ms and gc-ms/ms.one hundred and one tea samples including green tea, dark tea, scented tea, black tea, and oolong tea were screened and confirmed for the contamination of 31 organochlorine pesticides (ocps) and 19 pyrethroids (pys) by gas chromatography-negative chemical ionization-mass spectrometry (gc-nci-ms) and gas chromatography-tandem mass spectrometry (gc-ms/ms). 50 pesticides, 3 deuterium-labeled pys, and 24 (13)c-labeled ocps were separated well with the limits of detection (lods) ranging from 0.02 to ...201424964290
effectiveness of green tea mouthwash in comparison to chlorhexidine mouthwash in patients with acute pericoronitis: a randomized clinical trial.the objective of this study was to evaluate the effectiveness of green tea mouthwash in controlling the pain and trismus associated with acute pericoronitis in comparison to chlorhexidine (chx) mouthwash. ninety-seven patients with acute pericoronitis underwent debridement and received 5% green tea mouthwash (study group) or 0.12% chx mouth rinse (control group). pain (visual analogue scale; vas), number of analgesics, maximum mouth opening (mmo), and number of patients with trismus were determi ...201424954134
anti-inflammatory activity and molecular mechanism of oolong tea theasinensin.oolong tea theasinensins are a group of tea polyphenols different from green tea catechins and black tea theaflavins, and they are considered as bioactive compounds in oolong tea. in the present study, based on the properties of theasinensin and information about inflammatory processes, we investigated the anti-inflammatory activity and molecular mechanisms of theasinensin a (tsa) in both cell and animal models. in the cell model, tsa reduced the levels of pro-inflammatory mediators including in ...201424947273
tea consumption and risk of ischemic stroke: a brief review of the literature.stroke is an important cerebrovascular disease which causes chronic disability and death in patients. despite of its high morbidity and mortality, there are limited available effective neuroprotective agents for stroke. in recent years, the research aimed at finding novel neuroprotective agents from natural origins has been intensified. camellia sinensis l. (tea) is the second most consumed beverage worldwide, after water. it is classified into green and white, oolong, black and red, and pu-erh ...201424938891
residues and contaminants in tea and tea infusions: a review.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 ...201425164107
tea derived galloylated polyphenols cross-link purified gastrointestinal mucins.polyphenols derived from tea are thought to be important for human health. we show using a combination of particle tracking microrheology and small-angle neutron scattering that polyphenols acts as cross-linkers for purified gastrointestinal mucin, derived from the stomach and the duodenum. both naturally derived purified polyphenols, and green and black tea extracts are shown to act as cross-linkers. the main active cross-linking component is found to be the galloylated forms of catechins. the ...201425162539
black hairy tongue syndrome.black hairy tongue (bht) is a benign medical condition characterized by elongated filiform lingual papillae with typical carpet-like appearance of the dorsum of the tongue. its prevalence varies geographically, typically ranging from 0.6% to 11.3%. known predisposing factors include smoking, excessive coffee/black tea consumption, poor oral hygiene, trigeminal neuralgia, general debilitation, xerostomia, and medication use. clinical presentation varies but is typically asymptomatic, although aes ...201425152586
effects of tea intake on blood pressure: a meta-analysis of randomised controlled trials.the effect of tea intake on blood pressure (bp) is controversial. we performed a meta-analysis of randomised controlled trials to determine the changes in systolic and diastolic bp due to the intake of black and green tea. a systematic search was conducted in medline, embase and the cochrane controlled trials register up to may 2014. the weighted mean difference was calculated for net changes in systolic and diastolic bp using fixed-effects or random-effects models. previously defined subgroup a ...201425137341
epigalloccatechin-3-gallate inhibits ocular neovascularization and vascular permeability in human retinal pigment epithelial and human retinal microvascular endothelial cells via suppression of mmp-9 and vegf activation.epigalloccatechin-3-gallate (egcg) is the main polyphenol component of green tea (leaves of camellia sinensis). egcg is known for its antioxidant, anti-inflammatory, antiviral, and anti-carcinogenic properties. here, we identify egcg as a new inhibitor of ocular angiogenesis and its vascular permeability. matrix metalloproteinases (mmps) and vascular endothelial growth factor (vegf) play a key role in the processes of extracellular matrix (ecm) remodeling and microvascular permeability during an ...201425123184
effects of a pre-and post-workout protein-carbohydrate supplement in trained crossfit individuals.the purpose was to assess effects of a pre- and a post-workout protein-carbohydrate supplement on crossfit-specific performance and body composition.201425110627
simultaneous and enantioselective determination of cis-epoxiconazole and indoxacarb residues in various teas, tea infusion and soil samples by chiral high performance liquid chromatography coupled with tandem quadrupole-time-of-flight mass spectrometry.a novel and sensitive method for simultaneous enantiomeric analysis of two pesticides-cis-epoxiconazole and indoxacarb-in various teas, black tea infusion, and soil samples has been developed. the samples were initially subjected to acetonitrile extraction followed by cleanup using lab-made florisil/graphitized carbon black mixed solid phase extraction (spe) column (for the different teas and soil samples) and a bondelut c18-spe column (for the black tea infusion samples). separation of the anal ...201425108768
oolong, black and pu-erh tea suppresses adiposity in mice via activation of amp-activated protein kinase.it is well known that tea has a variety of beneficial impacts on human health, including anti-obesity effects. it is well documented that green tea and its constituent catechins suppress obesity, but the effects of other types of tea on obesity and the potential mechanisms involved are not yet fully understood. in this study, we investigated the suppression of adiposity by oolong, black and pu-erh tea and characterized the underlying molecular mechanism in vivo. we found that the consumption of ...201425098399
molecular cloning and expression analysis of tea plant aquaporin (aqp) gene family.the role of aquaporin proteins (aqps) has been extensively studied in plants. however, the information of aqps in the tea plant (camellia sinensis) is unclear. in this manuscript, we isolated 20 full-length aqp cdnas from the tea plant, and these sequences were classified into five subfamilies. the genes in these subfamilies displayed differential expression profiles in the studied tissues. the csaqp expression patterns correlated with flower development and opening (fdo) and bud endodormancy (b ...201425093260
rna-seq-mediated transcriptome analysis of actively growing and winter dormant shoots identifies non-deciduous habit of evergreen tree tea during winters.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 sho ...201425090269
rutin attenuates ethanol-induced neurotoxicity in hippocampal neuronal cells by increasing aldehyde dehydrogenase 2.rutin is derived from buckwheat, apples, and black tea. it has been shown to have beneficial anti-inflammatory and antioxidant effects. ethanol is a central nervous system depressant and neurotoxin. its metabolite, acetaldehyde, is critically toxic. aldehyde dehydrogenase 2 (aldh2) metabolizes acetaldehyde into nontoxic acetate. this study examined rutin's effects on aldh2 activity in hippocampal neuronal cells (ht22 cells). rutin's protective effects against acetaldehyde-based ethanol neurotoxi ...201425084483
plant growth-promoting rhizobacterial strain-mediated induced systemic resistance in tea (camellia sinensis (l.) o. kuntze) through defense-related enzymes against brown root rot and charcoal stump rot.induction of systemic resistance in host plants through microbes and their bioactive metabolites are attaining popularity in modern agricultural practices. in this regard, individual application of two strains of pseudomonas, rrlj 134 and rrlj 04, exhibited development of induced systemic resistance in tea plants against brown root rot and charcoal stump rot under split root experiments. the experimental findings also confirmed that the cuttings treated with fungal test pathogen and plant growth ...201425082766
the effect of black tea on blood pressure: a systematic review with meta-analysis of randomized controlled trials.epidemiological evidence has linked consumption of black tea, produced from camellia sinensis, with a reduced risk of cardiovascular diseases. however, intervention studies on the effects of tea consumption on blood pressure (bp) have reported inconsistent results. our objective was to conduct a systematic literature review with meta-analysis of controlled human intervention studies examining the effect of tea consumption on bp.201425079225
meta-analysis of black tea consumption and breast cancer risk: update 2013.black tea is a commonly consumed beverage in the world, comprising approximately 80% of all tea consumed. we sought to examine the association between black tea consumption and risk of breast cancer, using all available epidemiologic evidence to date. pubmed, embase, isi web of science, chinese national knowledge infrastructure database, and china biological medicine database were used to search for citations using the mesh terms as "breast neoplasm" and "black tea." then we performed a meta-ana ...201425077380
overexpression of camellia sinensis h1 histone gene confers abiotic stress tolerance in transgenic tobacco.overexpression of cshis in tobacco promoted chromatin condensation, but did not affect the phenotype. it also conferred tolerance to low-temperature, high-salinity, aba, drought and oxidative stress in transgenic tobacco. h1 histone, as a major structural protein of higher-order chromatin, is associated with stress responses in plants. here, we describe the functions of the camellia sinensis h1 histone gene (cshis) to illustrate its roles in plant responses to stresses. subcellular localization ...201425063323
the effect of iron and fat in a diet containing green tea extract (camellia sinensis) on the antioxidant capacity of some organs and the mrna expression of specific genes in mice.the hypothesis that iron and fat in the diet may affect green tea extract (gte) bioactivity, in particular antioxidant capacity and gene expression, was proposed and tested in mice. thirty mice were randomly assigned to have for 37 days free access to standard or high-fat diets with or without gte and ferrous lactate. mice were euthanized and specific organs were removed. total antioxidant capacity (tac) was measured using the ferric reducing antioxidant power (frap) and oxygen radical absorbanc ...201425055080
fermentation characteristics, tannin contents and in vitro ruminal degradation of green tea and black tea by-products ensiled at different temperatures.green and black tea by-products, obtained from ready-made tea industry, were ensiled at 10°c, 20°c, and 30°c. green tea by-product silage (gts) and black tea by-product silage (bts) were opened at 5, 10, 45 days after ensiling. fermentation characteristics and nutrient composition, including tannins, were monitored and the silages on day 45 were subjected to in vitro ruminal fermentation to assess anti-nutritive effects of tannins using polyethylene glycol (peg) as a tannin-binding agent. result ...201425050034
relationship between bladder cancer and total fluid intake: a meta-analysis of epidemiological evidence.epidemiological findings regarding the association between total fluid intake and bladder cancer risk have yielded varying results. our objective is to examine the possible associations between total fluid intake and bladder cancer risk.201425033957
green tea, black tea, and oolong tea polyphenols reduce visceral fat and inflammation in mice fed high-fat, high-sucrose obesogenic diets.green tea (gt) and caffeine in combination were shown to increase energy expenditure and fat oxidation, but less is known about the effects of black tea (bt) and oolong tea (ot). this study investigated whether decaffeinated polyphenol extracts from gt, bt, and ot decrease body fat and inflammation in male c57bl/6j mice fed high-fat/high-sucrose [hf/hs (32% energy from fat, 25% energy from sucrose)] diets. mice were fed either an hf/hs diet with 0.25% of polyphenol from gt, ot, or bt or a low-fa ...201425031332
[microbiological properties of two endophytic bacteria isolated from tea (camellia sinensis l.)].we investigated biological activities, physiological and biochemical properties of two endophytic bacteria isolated from fresh leaves of tea plants.201425007655
evaluation of plant phenolic metabolites as a source of alzheimer's drug leads.epidemiological studies have proven an association between consumption of polyphenols and prevention of alzheimer's disease, the most common form of dementia characterized by extracellular deposition of amyloid beta plaques. the aim of this study is pharmacological screening of the aqueous alcohol extract of markhamia platycalyx leaves, schotia brachypetala leaves and stalks, and piceatannol compared to aqueous alcohol extract of camellia sinensis leaves as potential alzheimer's disease drugs. l ...201424999480
molecular cloning, computational and expression analysis of anthocyanidin reductase in tea (camellia sinensis).tea [camellia sinensis (l.) o. kuntze] is one of the most popular non-alcoholic beverages rich in phenolic compounds, which includes epigallocatechin gallate (egcg), epigallocatechin (egc), epicatechin gallate (ecg), epicatechin (ec) and catechin (c). anthocyanidin reductase (anr) is responsible for catechin biosynthesis in plants, and analysis of its protein sequences and structures will be valuable for further research in the field. we have screened our dormant bud-specific complementary dna ( ...201424997573
compositional variation among black tea across geographies and their potential influence on endothelial nitric oxide and antioxidant activity.black tea (c. sinensis) consumption is well associated with enhanced endothelial function (ef) and reduced cardiovascular (cv) risk. this clinical end benefit is endorsed to flavonoids in tea. the black tea flavonoid composition varies across geographies and may impact its health benefits. moreover, the underlying functional species and a precise working mechanism responsible for the observed health benefit also remain to be investigated. in this article, we investigated the effect of black teas ...201424990074
l-theanine healed nsaid-induced gastric ulcer by modulating pro/antioxidant balance in gastric ulcer margin.l-theanine is a unique non-protein-forming amino acid present in tea [camellia sinensis (l.) o. kuntze]. in the present work, we evaluated the healing effect of l-theanine on nsaid (indomethacin)-induced gastric ulcer. histology of the stomach tissues revealed maximum ulceration on the third day after indomethacin administration (18 mg/kg, single dose p.o.) which was accompanied by increased lipid peroxidation; protein carbonylation; th1 cytokine synthesis, and depletion of thiol, mucin, prostag ...201424981317
antagonistic effects of black tea against gamma radiation-induced oxidative damage to normal lymphocytes in comparison with cancerous k562 cells.the potential of naturally occurring antioxidants to reduce the cellular oxidative damage induced by ionizing radiation has been studied for more than a decade for their pharmacological application during cancer treatment. it is already known that radioprotective efficacy of phytochemicals might influence various end points of radiation damage. flavonoids are well-known natural radioprotectors, and their biological effects depend upon their chemical structure. in the present study, radioprotecti ...201424981250
new phenylpropanoid-substituted flavan-3-ols from pu-er ripe tea.pu-er ripe tea is a special microbial post-fermented tea made from pu-er raw tea, a kind of green tea produced from the leaves of camellia sinensis var. assamica. it is one of the most consumed teas in the past two decades in china, due to its special flavor, taste, and beneficial effects. this work aimed to obtain diverse catechin structures from pu-er ripe tea, which led to the isolation of four new phenylpropanoid-substituted flavan-3-ols, puerins c-f (1-4), together with four known flavan-3- ...201425233599
metabolic stability and inhibitory effect of o-methylated theaflavins on h2o2-induced oxidative damage in human hepg2 cells.seven new o-methylated theaflavins (tfs) were synthesized by using o-methyltransferase from an edible mushroom. using tfs and o-methylated tfs, metabolic stability in pooled human liver s9 fractions and inhibitory effect on h(2)o(2)-induced oxidative damage in human hepg2 cells were investigated. in o-methylation of theaflavin 3'-o-gallate (tf3'g), metabolic stability was potentiated by an increase in the number of introduced methyl groups. o-methylation of tf3,3'g did not affect metabolic stabi ...201425229848
tmdb: a literature-curated database for small molecular compounds found from tea.tea is one of the most consumed beverages worldwide. the healthy effects of tea are attributed to a wealthy of different chemical components from tea. thousands of studies on the chemical constituents of tea had been reported. however, data from these individual reports have not been collected into a single database. the lack of a curated database of related information limits research in this field, and thus a cohesive database system should necessarily be constructed for data deposit and furth ...201425224438
cytochrome p450 3a4 and 2d6-mediated metabolism of leisure and medicinal teas.thirty-five commercially available camellia sinensis (black and green) and herbal leisure teas and an assortment of traditional chinese medicinal teas were randomly selected and examined for their potential to inhibit the drug metabolizing enzyme cytochrome p450 3a4 (cyp3a4). the study was then extended to examine cyp2d6*1 and cyp2d6*10.201425224344
transcriptome analysis of indole-3-butyric acid-induced adventitious root formation in nodal cuttings of camellia sinensis (l.).tea (camellia sinensis l.) is a popular world beverage, and propagation of tea plants chiefly depends on the formation of adventitious roots in cuttings. to better understand potential mechanisms involved in adventitious root formation, we performed transcriptome analysis of single nodal cuttings of c. sinensis treated with or without indole-3-butyric acid (iba) using the illumina sequencing method. totally 42.5 million rna-seq reads were obtained and these were assembled into 59,931 unigenes, w ...201425216187
discrimination of chinese teas with different fermentation degrees by stepwise linear discriminant analysis (s-lda) of the chemical compounds.this study aimed to construct objective and accurate analytical models of tea categories based on their polyphenols and caffeine. a total of 522 tea samples of 4 commonly consumed teas with different fermentation degrees (green tea, white tea, oolong tea, and black tea) were analyzed by high-performance liquid chromatography (hplc) coupled with spectrophotometry, utilizing iso 14502, as analytical tools. the content of polyphenols and caffeine varied significantly according to differently fermen ...201425211192
determination of catechin content in representative chinese tea germplasms.to understand tea germplasms better and to use them effectively for production and breeding, the catechin content of 403 accessions of representative tea germplasms collected from various locations in china were studied using hplc. the catechin content of these tea germplasms varied from 56.6 to 231.9 mg/g and averaged 154.5 ± 18.1 mg/g. one germplasm with low total catechin (tc) content (<60 mg/g) and three with high tc (>200 mg/g) contents were found. averages of the tc content of the three va ...201425204786
tea consumption and lung cancer risk: a meta-analysis of case-control and cohort studies.recent epidemiologic studies, especially cohort and case-control studies, have yielded inconsistent findings regarding the association between tea consumption and risk for lung cancer. the aim of this study was to assess a potential relationship between tea consumption and the incidence of lung cancer worldwide.201425194612
the antimicrobial possibilities of green tea.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 antimicrobi ...201425191312
occurrence of 15 + 1 eu priority polycyclic aromatic hydrocarbons (pah) in various types of tea (camellia sinensis) and herbal infusions.for the analysis of 15 + 1 eu priority pah in tea and herbal infusions, an online-spe-lvi-gc-ms method was developed. this method includes sample extraction of the tea and herbal infusions with saponification followed by an automated spe clean-up step. for brews a liquid-liquid extraction with cyclohexane was performed before an automated spe clean-up. gas chromatographic separation was done using an agilent j&w select pah (15 m × 0.15 mm × 0.10 µm) column, which allows the separation of the thr ...201425186127
antimutagenic and anticancer activity of darjeeling tea in multiple test systems.darjeeling tea, a most popular variety of black tea, though consumed by the people in different parts of world but its beneficial health effects have not been investigated in details. in this study, the antimutagenic and anticancer effect of darjeeling tea extract (dte) has been evaluated.201425183356
the galloyl catechins contributing to main antioxidant capacity of tea made from camellia sinensis in china.total polyphenol content, catechins content, and antioxidant capacities of green, dark, oolong, and black teas made from camellia sinensis in china were evaluated. the total polyphenol content of 20 samples of tea was in the range of 7.82-32.36%. total catechins content was in the range of 4.34-24.27%. the antioxidant capacity of tea extract was determined by the oxygen radical absorbance capacity (orac) test and the 1,1-diphenyl-2-picrylhydrazyl (dpph) radical-scavenging test. total polyphenol ...201425243234
comparison of the inhibition of monoamine oxidase and butyrylcholinesterase activities by infusions from green tea and some citrus peels.this study sought to investigate the effect of infusions from green tea (camellia sinensis) and some citrus peels [shaddock (citrus maxima), grapefruit (citrus paradisi), and orange (citrus sinensis)] on key enzymes relevant to the management of neurodegenerative conditions [monoamine oxidase (mao) and butyrylcholinesterase (bche)]. the total phenol contents and antioxidant activities as typified by their 2,2(')-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) (abts) radicals scavenging abiliti ...201425243093
a phase ii clinical trial of a natural formulation containing tea catechins for xerostomia.previous animal studies indicated catechins from the tea plant (camellia sinensis) may modulate salivary function and possess a therapeutic effect for xerostomia. the objective of this study was to evaluate a natural formulation containing tea catechins in 60 patients with xerostomia, including patients with sjögren syndrome.201425240992
effect of black tea consumption on blood cholesterol: a meta-analysis of 15 randomized controlled trials.the results of the studies that have investigated the effects of black tea on blood cholesterol are inconsistent. the aim of this study is to quantitatively assess the effects of black tea on cholesterol concentrations.201425237889
molecular mechanisms by which white tea prevents oxidative stress.the flavonoid content of tea (camellia sinensis) has beneficial properties in the prevention of diseases. however, the mechanisms by which white tea can protect against oxidative stress remain unclear. to shed light on this issue, rats were given distilled water (controls), 0.15 mg/day (dose 1) or 0.45 mg/day (dose 2) of solid tea extract/kg body weight for 12 months. all the animals received an injection of adriamycin (adr; 10 mg/kg body weight), except half of the control group, which were giv ...201425255956
camellia sinensis (l.) kuntze extract ameliorates chronic ethanol-induced hepatotoxicity in albino rats.the goal of this study was to investigate the hepatoprotective effects of aqueous extract of camellia sinensis or green tea extract (aqgte) in chronic ethanol-induced albino rats. all animals were divided into 4 groups in the study for a 5-week duration. 50% ethanol was given orally to the rats with two doses (5 mg/kg bw and 10 mg/kg bw) of aqgte. ethanol administration caused a significant increase in the levels of plasma and serum enzymatic markers, alanine aminotransferase (alt), aspartate am ...201425254057
the role of phytochemicals as micronutrients in health and disease.intake of dietary phytochemicals has frequently been associated with health benefits. noninfectious diseases including cardiovascular disease (cvd), cancer and diabetes are major causes of death, whereas dementia cases are also increasing to 'epidemic' proportion. this review will focus on recent progress on mechanisms underlying the potential role of dietary phytochemicals in cvd, diabetes, cancer and dementia, with consideration of the latest clinical data.201425252018
assessment of anti-nutritive activity of tannins in tea by-products based on in vitro rumen fermentation.nutritive values of green and black tea by-products and anti-nutritive activity of their tannins were evaluated in an in vitro rumen fermentation using various molecular weights of polyethylene glycols (peg), polyvinyl pyrrolidone (pvp) and polyvinyl polypyrrolidone as tannin-binding agents. significant improvement in gas production by addition of peg4000, 6000 and 20000 and pvp was observed only from black tea by-product, but not from green tea by-product. all tannin binding agents increased nh ...201425358316
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