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coffee and black tea consumption and breast cancer mortality in a cohort of swedish women.coffee and black tea contain a mixture of compounds that have the potential to influence breast cancer risk and survival. however, epidemiologic data on the relation between coffee and black tea consumption and breast cancer survival are sparse.201222836509
black tea polyphenols reverse epithelial-to-mesenchymal transition and suppress cancer invasion and proteases in human oral cancer cells.epithelial-to-mesenchymal transition (emt) in cancer cells is considered to be a prerequisite for acquiring invasive/migratory phenotype and subsequent metastasis. this study provides molecular evidence associated with the antimetastatic effect of black tea polyphenol extracts (bte), which contain polyphenols including gallic acid, gallocatechin, catechin, epigallocatechin-3-gallate, epicatechin-3-gallate, and theaflavin 3,3'-digallate, in an an oral squamous cell culture system by showing a nea ...201222827697
natural products: a safest approach for obesity.obesity is recognized as a social problem, associated with serious health risks and increased mortality. numerous trials have been conducted to find and develop new anti-obesity drugs through herbal sources to minimize adverse reactions associated with the present anti-obesity drugs. the use of natural products as medicine has been documented for hundreds of years in various traditional systems of medicines throughout the world. this review focuses on the medicinal plants such as achyranthus asp ...201222821661
green and black tea intake in relation to prostate cancer risk among singapore chinese.tea is one of the most commonly consumed beverages worldwide. to date, observational data from prospective cohort studies investigating the relationship between green and black tea intake and prostate cancer risk are sparse and equivocal. in a population-based, prospective cohort study of chinese men in singapore, we investigated the relationship between green and black tea intake and prostate cancer risk.201222864870
changes of growth, photosynthesis and alteration of leaf antioxidative defence system of tea [camellia sinensis (l.) o. kuntze] seedlings under aluminum stress.tea [camellia sinensis (l.) o. kuntze] is an aluminum (al) hyperaccumulator plant and is commercially important due to its high content of antioxidants. although al induced growth is well-known for the plants growing in acid soil, yet the cause underlying the stimulatory effect of al has not been fully understood. to investigate the possible role of al in growth induction, we studied morphological, physiological as well as biochemical changes of tea plant under different al concentrations (0-4,0 ...201222850809
green tea polyphenols for the protection against renal damage caused by oxidative stress.green tea, prepared from the leaves of camellia sinensis l., is a beverage that is popular worldwide. polyphenols in green tea have been receiving much attention as potential compounds for the maintenance of human health due to their varied biological activity and low toxicity. in particular, the contribution of antioxidant activity to the prevention of diseases caused by oxidative stress has been focused upon. therefore, in this study, we investigated the effects of (-)-epigallocatechin 3-o-gal ...201222844338
polymeric black tea polyphenols modulate the localization and activity of 12-o-tetradecanoylphorbol-13-acetate-mediated kinases in mouse skin: mechanisms of their anti-tumor-promoting action.polymeric black tea polyphenols (pbps) have been shown to possess anti-tumor-promoting effects in two-stage skin carcinogenesis. however, their mechanisms of action are not fully elucidated. in this study, mechanisms of pbp-mediated antipromoting effects were investigated in a mouse model employing the tumor promoter 12-o-tetradecanoylphorbol-13-acetate (tpa). compared to controls, a single topical application of tpa to mouse skin increased the translocation of protein kinase c (pkc) from cytoso ...201222841871
evaluation of anti-inflammatory effects of green tea and black tea: a comparative in vitro study.the present study was conducted to evaluate and compare the anti-inflammatory effects of aqueous extracts of green tea and black tea leaves (camellia sinensis) against the denaturation of protein in vitro. the test extracts at different concentrations were incubated with egg albumin under controlled experimental conditions and subjected to determination of absorbance to assess the anti-inflammatory property. diclofenac sodium was used as the reference drug. the present results exhibited a concen ...201222837963
synthesis of silver nanoparticles by using tea leaf extract from camellia sinensis.the development of the biological synthesis of nanoparticles using microorganisms or plant extracts plays an important role in the field of nanotechnology as it is environmentally friendly and does not involve any harmful chemicals. in this study, the synthesis of silver nanoparticles using the leaves extract of chinese tea from camellia sinensis is reported. the synthesized nanoparticles were characterized using uv-vis spectroscopy, x-ray diffraction (xrd), transmission electron microscopy (tem ...201222904632
evidence that the ceratobasidium-like white-thread blight and black rot fungal pathogens from persimmon and tea crops in the brazilian atlantic forest agroecosystem are two distinct phylospecies.the white-thread blight and black rot (wtbr) caused by basidiomycetous fungi of the genus ceratobasidium is emerging as an important plant disease in brazil, particularly for crop species in the ericales such as persimmon (diospyros kaki) and tea (camellia sinensis). however, the species identity of the fungal pathogen associated with either of these hosts is still unclear. in this work, we used sequence variation in the internal transcribed spacer regions, including the 5.8s coding region of rd ...201222888299
antioxidant activities of extracts from teas prepared from medicinal plants, morus alba l., camellia sinensis l., and cudrania tricuspidata , and their volatile components.the antioxidant activity of essences of teas prepared from mulberry ( morus alba l.), camellia sinensis l., and cudrania tricuspidata (carr.) burea plant was examined using two antioxidant assays. selected volatile chemicals identified in these plants were also tested for antioxidant activity. all extracts exhibited antioxidant activity with a clear dose response in the aldehyde/carboxylic acid and the malonaldehyde/gas chromatography (ma/gc) assays. antioxidant activity of extracts at the level ...201222871255
coffee and tea consumption and risk of lung cancer: a dose-response analysis of observational studies.results from the recent meta-analysis suggested a favorable effect of green tea consumption and risk of lung cancer, while no significant association was found between black tea consumption and risk of lung cancer. besides, a significantly positive association was found between coffee consumption and risk of lung cancer. however, the relationship of green tea and coffee consumption is unclear. thus the dose-response relationship was assessed by restricted cubic spline model and multivariate rand ...201222964413
antioxidant capacity of teas and herbal infusions: polarographic assessment.hydrogen peroxide scavenging (hps) activity of unfermented (green, yellow, and white), partially fermented (oolong), and completely fermented (black) tea ( camellia sinensis ), maté ( ilex paraguariensis ), and various herbal infusions, as well as individual compounds (flavan-3-ols, flavonols, cinnamic and benzoic acids, and methylxanthines), was assessed by recently developed direct current (dc) polarographic assay. correlations of tea and herbal infusion hps activity with total phenolic conten ...201222950743
growth inhibition of walker carcinosarcoma 256 with alcoholic extract of green tea leaves (camellia sinensis).to evaluate the antitumor activity of alcoholic extracts of green tea (camella sinensis).201222936089
l-theanine attenuates abstinence signs in morphine-dependent rhesus monkeys and elicits anxiolytic-like activity in mice.l-theanine, 2-amino-4-(ethylcarbamoyl) butyric acid, an amino acid found in green tea (camellia sinensis), is sold in the united states as a dietary supplement to reduce stress and improve cognition and mood. the observations that l-theanine has been shown to inhibit caffeine's stimulatory effects and that caffeine produces precipitated withdrawal signs in opioid-addicted monkeys and some opioid withdrawal signs in some normal monkeys, suggest that l-theanine may suppress opioid withdrawal signs ...201222935630
[assessment of stimulant use especially caffeine intake in selected group of the breastfeeding women].taking into account the negative impact of stimulants, including alcohol, nicotine and excessive consumption of caffeine on the baby and his mother, a very important is to stop or to restrict their use, especially during pregnancy and lactation.201222928364
determination of cd (ii), cu (ii), and pb (ii) in some foods by faas after preconcentration on modified silica gels with thiourea.this study describes preconcentration method for determination of cd (ii), cu (ii), and pb (ii) in some food samples. silica gel was modified with thiourea and characterized by ir and c, h, n, s elemental analysis. modified silica gel was used as a solid phase extraction for determination of cd (ii), cu (ii) and pb (ii) in tuna fish, biscuit, black tea, rice, kaşar cheese, honey, tomato paste, and margarine samples. the analytical conditions including eluent type, ph of sample solutions, flow ra ...201222924612
impedance study of tea with added taste compounds using conducting polymer and metal electrodes.in this study the sensing capabilities of a combination of metals and conducting polymer sensing/working electrodes for tea liquor prepared by addition of different compounds using an impedance mode in frequency range 1 hz-100 khz at 0.1 v potential has been carried out. classification of six different tea liquor samples made by dissolving various compounds (black tea liquor + raw milk from milkman), (black tea liquor + sweetened clove syrup), (black tea liquor + sweetened ginger syrup), (black ...201223035436
in vitro screening of medicinal plants used in mexico as antidiabetics with glucosidase and lipase inhibitory activities.this work shows the inhibitory effect on glucosidase and lipase enzymes of 23 medicinal plants described as traditional treatments for diabetes in several mexican sources. hydroalcoholic extracts of selected plants were evaluated at 1 mg/ml for glucosidase and 0.25 mg/ml for lipase inhibitory activities, respectively. camellia sinensis, acarbose, and orlistat were used as positive controls. dose-response curves were done with the most active species. sixty percent of all tested extracts inhibite ...201223082084
gut microbial metabolism of polyphenols from black tea and red wine/grape juice is source-specific and colon-region dependent.the colonic microbial degradation of a polyphenol-rich black tea extract (bte) and red wine/grape juice extract (rwge) was compared in a five-stage in vitro gastrointestinal model (twinshime). microbial metabolism of bte and rwge polyphenols in the twinshime was studied subsequently in single- and continuous-dose experiments. a combination of liquid or gas chromatography with mass spectrometry (lc-ms or gc-ms) and nmr-based metabolic profiling was used to measure selected parent polyphenols, the ...201223072624
planar solid phase extraction clean-up for pesticide residue analysis in tea by liquid chromatography-mass spectrometry.efficient clean-up is indispensable for preventing matrix effects in multi-residue analysis of pesticides in food by liquid and gas chromatography (lc and gc) coupled to mass spectrometry (ms). high-throughput planar solid phase extraction (htpspe) was recently introduced as a new clean-up concept in residue analysis of pesticides in fruit and vegetables (c. oellig, w. schwack, 2011 [45]). thin-layer chromatography (tlc) was used to completely separate pesticides from matrix compounds and to foc ...201222981507
characterisation of volatile and non-volatile metabolites in etiolated leaves of tea (camellia sinensis) plants in the dark.aroma is an essential factor affecting the quality of tea (camellia sinensis) products. while changes of volatile compounds during tea manufacturing have been intensively studied, the effect of environmental factors on volatile contents of fresh tea leaves has received less attention. we found that c. sinensis var. yabukita kept in darkness by shading treatment for 3 weeks developed etiolated leaves with significantly increased levels of volatiles, especially volatile phenylpropanoids/benzenoids ...201222980801
incompatibility between propericiazine oral solution and tea-based drink.here, we studied the incompatibility between an oral solution of propericiazine (pcz), an antipsychotic drug, and various commercially available bottled tea-based drinks. when 0.5 ml of the pcz oral solution (10 mg/ml) was mixed with 16.5 ml of a tea-based drink (such as green tea, oolong tea, and black tea), the residual pcz content declined to approximately 50% in some mixed solutions. after mixing with other tea-based drinks, the residual pcz content declined to approximately 30%, while in ot ...201222976331
hypoglycemic and antilipidemic properties of kombucha tea in alloxan-induced diabetic rats.diabetes has become a serious health problem and a major risk factor associated with troublesome health complications, such as metabolism disorders and liver-kidney dysfunctions. the inadequacies associated with conventional medicines have led to a determined search for alternative natural therapeutic agents. the present study aimed to investigate and compare the hypoglycemic and antilipidemic effects of kombucha and black tea, two natural drinks commonly consumed around the world, in surviving ...201222591682
optimizing the orosensory properties of model functional beverages: the influence of novel sweeteners, odorants, bitter blockers, and their mixtures on (+)-catechin.the use of flavor-modifying strategies are important to improving the sensory profile of some excessively bitter and astringent functional ingredients, such as (+)-catechin (cat). two bitter blockers (ß-cyclodextrin [cyclo], homoeriodictyol sodium salt [hed]), two sweeteners (sucrose [suc], rebaudioside a [reb]), and two odorants (vanillin [van], black tea aroma [tea]) were assessed for their efficacy at modifying the bitterness and astringency of cat in model aqueous solutions. the intensity of ...201222582876
effect of salt treatment on theanine biosynthesis in camellia sinensis seedlings.theanine synthetase (ts) is an enzyme involved in theanine biosynthesis in tea plants. recent studies have revealed that theanine biosynthesis, derived from nitrogen metabolism in tea (camellia sinensis l.) plants, could be influenced by salt treatment. we have characterized csts at the molecular and biochemical level. the expression pattern of csts protein was examined by western blot using a self-prepared polyclonal antibody with high specificity and sensitivity. the effect of salt treatment o ...201222579942
slimquick™ - associated hepatotoxicity in a woman with alpha-1 antitrypsin heterozygosity.green tea (camellia sinensis)-associated hepatotoxicity is reported. however, the presence of alpha-1 antitrypsin mz phenotype as a predisposing factor to green tea-associated drug-induced liver injury (dili) is unknown. a previously healthy woman with alpha-1 antitrypsin mz phenotype who took slimquick™, an herbal supplement containing green tea extract, developed severe hepatotoxicity requiring corticosteroid treatment. green tea-associated hepatotoxicity is reviewed and alpha-1 antitrypsin mz ...201222567188
identification of drought tolerant progenies in tea by gene expression analysis.understanding the genes that govern tea plant (camellia sinensis) architecture and response to drought stress is urgently needed to enhance breeding in tea with improved water use efficiency. field drought is a slow mechanism and the plants go through an adaptive process in contrast to the drastic changes of rapid dehydration in case of controlled experiments. we identified a set of drought responsive genes under controlled condition using ssh, and validated the identified genes and their patter ...201222562548
tiadinil, a plant activator of systemic acquired resistance, boosts the production of herbivore-induced plant volatiles that attract the predatory mite neoseiulus womersleyi in the tea plant camellia sinensis.plants respond with various defense mechanisms to pathogenic or herbivorous attack. some chemicals called plant activators that induce the plant defense response against pathogens have been commercially used to protect plants. here we studied the effects of tiadinil (tdl) on defense mechanisms against herbivores. tdl suppresses pathogenic fungi on tea leaves by inducing defense mechanisms. we used one of the major trophic systems in tea consisting of the herbivorous mite, tetranychus kanzawai, a ...201222669277
determination of essential and non-essential elements in various tea leaves and tea infusions consumed in turkey.tea is one of the most popular beverages in the world. thus, the chemical components in tea are of great interest, especially in relation to health. in this study, 12 tea samples (10 black, 1 white and 1 green) and 5 herbal tea samples were purchased from supermarkets in izmir, turkey. sample preparation has been performed using wet and microwave digestion procedures. the elemental content (fe, zn, cu, mn, ni, na and k) in the digests and infusions has been analysed. generally, elemental content ...201224779742
evaluation of ultrasound and light sources as bleaching catalysts - an in vitro study.to evaluate the efficacy of tooth bleaching with high concentration agents, varying the catalyst sources and exposure times.201222645732
flavor characteristics of seven grades of black tea produced in turkey.seven grades of black tea [high-quality black tea (grades 1-3) and low-quality black tea (grades 4-7)], processed by çaykur tea processing plant (rize, turkey), were compared for their differences in descriptive sensory analysis (dsa), aroma-active compounds (volatile compounds), and taste-active compounds (sugar, organic acid, and free amino acid compositions). ten flavor attributes such as 'after taste', 'astringency', 'bitter', 'caramel-like', 'floral/sweet', 'green/grassy', 'hay-like', 'malt ...201222642545
theaflavin ameliorates behavioral deficits, biochemical indices and monoamine transporters expression against subacute 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (mptp)-induced mouse model of parkinson's disease.evidence from clinical and experimental studies indicates that degeneration of nigrostriatal dopaminergic neurons is a pathological hallmark of parkinson's disease (pd). the present study was designed to investigate the neuroprotective potential of theaflavin (tf) on oxidative stress, monoamine transporters and behavioral abnormalities in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (mptp)-induced neurodegeneration. tf, a black tea polyphenol, has been known to possess neuroprotective effects ag ...201222634505
polyphenolic compounds are novel protective agents against lipid membrane damage by α-synuclein aggregates in vitro.cumulative evidence now suggests that the abnormal aggregation of the protein α-synuclein (αs) is a critical factor in triggering neurodegeneration in parkinson's disease (pd). in particular, a fundamental pathogenetic mechanism appears to involve targeting of neuronal membranes by soluble oligomeric intermediates of αs, leading to their disruption or permeabilisation. therefore, a model assay was developed in which fluorophore-loaded unilamellar vesicles were permeabilised by soluble oligomers, ...201222634381
inhibition of eph receptor-ephrin ligand interaction by tea polyphenols.tea contains a variety of bioactive chemicals, such as catechins and other polyphenols. these compounds are thought to be responsible for the health benefits of tea consumption by affecting the function of many cellular targets, not all of which have been identified. in a high-throughput screen for small molecule antagonists of the epha4 receptor tyrosine kinase, we identified five tea polyphenols that substantially inhibit epha4 binding to a synthetic peptide ligand. further characterization of ...201222750215
evaluation of dextrose water, black tea and orange juice on histopathologic recovery of surgery-induced intestinal damage in rabbits.the increase in intestinal permeability following damage to the intestinal mucosa in any surgical procedure, trauma or fasting is well- known.201224350105
black tea polyphenols induce human leukemic cell cycle arrest by inhibiting akt signaling: possible involvement of hsp90, wnt/β-catenin signaling and foxo1.tea polyphenols have potent biological activities against human cancer cells. a major causative factor in malignancies is disregulation of cell-cycle kinetics. in this study, we observed that black tea polyphenols, theaflavins (tf) and thearubigins (tr) induced cell-cycle arrest at the g(0) /g(1) phase in human leukemic u937 and k562 cells. our objective was to understand the underlying molecular mechanism of cell-cycle inhibition by tf and tr. during elucidation, we observed that both tf and tr ...201222715906
evaluation of oral subchronic toxicity of pu-erh green tea (camellia sinensis var. assamica) extract in sprague dawley rats.pu-erh green tea, originally produced in the yunnan province of p.r. china for about 1700 years, is believed to be beneficial to health in asian countries. the potential toxicity of pu-erh green tea when administered at high doses via concentrated extract, however, has not been completely investigated.201222710291
regular black tea habit could reduce tobacco associated ros generation and dna damage in oral mucosa of normal population.tobacco and tea habit are very common in world wide. in the present study, an attempt was made to evaluate the effect of regular drinking of black tea on reactive oxygen species (ros) generation and dna damage in buccal cells of normal subjects with or without tobacco habit. expression of ros associated proteins iκb, nf-κb as well as dna repair associated proteins p53, mlh1 were also analyzed. exfoliated buccal cells were collected from 308 healthy individuals and classified according to age, to ...201222705326
a minireview of analytical methods for the geographical origin analysis of teas (camellia sinensis).chemical compositions in tea leaves are influenced by their growing surrounding, and the content of these components are related to the quality of teas. the determination of the concentration of chemical composition in teas will predict the ranking of teas and indicate the geographical origins. this overview concerns an investigation of analytical methods that are being used for the determination of the geographical origin of tea. the analytical approaches have been subdivided into three groups: ...201222698268
tea consumption and the risk of overall and grade specific prostate cancer: a large prospective cohort study of scottish men.tea may be a potentially modifiable and highly prevalent risk factor for the most common cancer in men, prostate cancer. however, associations between black tea consumption and prostate cancer in epidemiological studies have been inconsistent, limited to a small number of studies with small numbers of cases and short follow-up periods and without grade-specific information. we conducted a prospective cohort study of 6,016 men who were enrolled in the collaborative cohort study between 1970 and 1 ...201222697604
medicinal flowers. xxxiii. anti-hyperlipidemic and anti-hyperglycemic effects of chakasaponins i-iii and structure of chakasaponin iv from flower buds of chinese tea plant (camellia sinensis).effects of principal saponins, chakasaponins i-iii, from the flower buds of camellia sinensis cultivated in fujian province, china on plasma triglyceride (tg) and glucose levels in olive oil or sucrose-loaded mice were examined. chakasaponins i-iii at 50 and 100 mg/kg significantly inhibited increases in plasma tg and glucose levels. furthermore, they prevented gastric emptying, suggesting that the former inhibitory effect is partly dependent on the inhibition of gastric emptying. in addition, t ...201222689407
triterpene saponins with hyaluronidase inhibitory activity from the seeds of camellia sinensis.the meoh extract of the seeds of camellia sinensis (l.) kuntze gave twelve new saponins (1-12) along with ten known saponins (13-22). these saponins (1-22) showed stronger hyaluronidase inhibitory activity than the positive control, rosmarinic acid.201222689399
black tea and blood pressure: did the blood pressure fall or rise? 201222688998
determination of theanine and gamma-aminobutyric acid in tea by high performance- liquid chromatography with precolumn derivatization.a method of precolumn derivatization-high performance liquid chromatography (hplc) for the determination of theanine and gamma-aminobutyric acid (gaba) in tea was established. o-phthalaldehyde (opa) and n-acetyl-l-cysteine (nac) were chosen as the derivatization reagents. the effects of teapolyphenol (tp), proline (pro) and vitamin c (vc) on derivatization yields were investigated. the results indicated that vc not only stabilized the stock solution of opa, but also enhanced the yield of gaba de ...201222679834
discoloration of manually fabricated resins and industrially fabricated cad/cam blocks versus glass-ceramic: effect of storage media, duration, and subsequent polishing.this study determined the discoloration of five cad/cam resins, four manually polymerized resins, and glass-ceramic as control group. specimens were divided into three groups (n=300, n=30) to be stored in coffee, black tea and red wine (n=10). the discoloration was measured using a spectrophotometer after 1, 7, 29, 90, 180 days storage. all tested groups showed color change (δe) at all time points. the manually polymerized resin composites gd (gradia) and cm (cronmix k), and the cad/cam resin co ...201222673470
preparation and application of steeps of tea as new simulations of urine for the performance testing programme of 14c.(14)c is one of the radionuclides for which the canadian nuclear safety commission has developed performance testing programmes (ptps). during the ptp exercises, clients receive samples of natural urine containing spiked radionuclides, for testing. in these programmes, urine has disadvantages. these include (1) slow collection times from donors, (2) unpleasant smell and (3) potential to transmit diseases. to assist in solving some of these problems, the canadian national calibration reference ce ...201222451164
health-promoting effects of green tea.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 egc ...201222450537
diversity of catechin in northeast indian tea cultivars.tea (camellia sinensis l.) leaf contains a large amount of catechins (a group of very active flavonoids) which contribute to major quality attributes of black tea. based on morphological characters tea plants were classified as assam, china, and cambod varieties. the present study is an attempt for biochemical fingerprinting of the tea varieties based on catechin composition in green leaf of cultivars grown in northeast india. assam variety cultivars contained the highest level of catechins foll ...201222448135
protective effect of theaflavins on neuron against 6-hydroxydopamine-induced apoptosis in sh-sy5y cells.theaflavins, the oxidation products of tea polyphenols are important biologically active components of black tea. 6-hydroxydopamine is a pro-parkinsonian neurotoxin. theaflavins could inhibit the auto-oxidation of 6-hydroxydopamine in a dose-dependent manner from 0.5 µg/ml to 25 µg/ml. here we investigated the protective effect of theaflavins on 6-hydroxydopamine induced sh-sy5y cells against apoptosis (within this concentration range). it was found that pretreating sh-sy5y cells with 0.5 µg/ml ...201222448094
epicatechin: endothelial function and blood pressure.epidemiological studies indicate an inverse relationship between flavanol intake and the risk of cardiovascular disease. potential mechanisms include their effects on endothelial function and hypertension. a number of studies have shown that flavanol-rich cocoa reduces blood pressure and endothelial dysfunction, whereas black tea may have opposite effects. these results highlight the importance of the different effects of the multitude of phytochemical constituents in these foods and the need fo ...201222440087
a new norisoprenoid and other compounds from fuzhuan brick tea.fuzhuan brick tea, a kind of dark tea consumed mainly in the border regions of southwestern and northwestern china since the 1860s, is produced from the leaves of camellia sinensis var. sinensis by microbial fermentation. from this special fermented tea, a new norisoprenoid, 3r,9r-oxido-5-megastigmene, was isolated, together with α-linolenic acid, strictin, isovitexin, astragalin, (+)-catechin, (-)-epicatechin, (-)-epicatechin gallate, (+)-gallocatechin, (-)-epigallocatechin, (-)-epigallocatechi ...201222430120
chemical analysis and acetylcholinesterase inhibitory effect of anthocyanin-rich red leaf tea (cv. sunrouge).the purpose of this study was to evaluate the effects of leaf order or crop season on anthocyanins and other chemicals in the anthocyanin-rich tea cultivar 'sunrouge' (camellia sinensis x c. taliensis) by using high-performance liquid chromatography, and to study the effect of 'sunrouge' extract on acetylcholinesterase (ache) activity in human neuroblastoma sk-n-sh cells.201222419270
inhibition of acetylcholinesterase by green and white tea and their simulated intestinal metabolites.by 2034 it is forecast that 5% of the global population will be aged 85 years or over--approximately two and half fold increase on present day figures--which will inevitably lead to an increase in age-associated disorders such as alzheimer's disease. there is mounting evidence that green tea (camellia sinensis) possesses numerous health-promoting properties, and may potentially be beneficial to those suffering from alzheimer's and other diseases, including cardiovascular disease and cancer. thes ...201222418730
the effects of green tea polyphenols on drug metabolism.tea, made from the dried leaves of the plant camellia sinensis theaceae, is a very popular beverage consumed worldwide. recently, green tea extract-based dietary supplements have also been widely consumed for the acclaimed beneficial health effects, such as weight reduction. although tea consumption is considered to be innocuous, the potential interactions between tea polyphenols and drugs have been demonstrated in studies in vitro and in vivo.201222509899
maldi-tof mass spectrometry: avoidance of artifacts and analysis of caffeine-precipitated sii thearubigins from 15 commercial black teas.thearubigins are the quantitatively major phenolic compounds in black tea, accounting for some 60-70% of the solids in a typical black tea infusion. maldi-tof mass spectra for caffeine-precipitated sii thearubigins (sii ctrs) from 15 different commercial teas support previous conclusions that sii ctrs are polyhydroxylated oligomers (rather than polymers) of catechins and catechin gallates in redox equilibrium with their quinone counterparts. some 4500 peaks were revealed in a mass range from m/z ...201222509842
mining for ssrs and fdms from expressed sequence tags of camellia sinensis.simple sequence repeats (ssrs) developed from expressed sequence tags (ests), known as est-ssrs are most widely used and potentially valuable source of gene based markers for their high levels of crosstaxon portability, rapid and less expensive development. the est sequence information in the publicly available databases is increasing in a faster rate. the emerging computational approach provides a better alternative process of development of ssr markers from the ests than the conventional metho ...201222493533
a shared response of thaumatin like protein, chitinase, and late embryogenesis abundant protein3 to environmental stresses in tea [camellia sinensis (l.) o. kuntze].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 plan ...201222543414
csnam-like protein encodes a nuclear localized protein and responds to varied cues in tea [camellia sinensis (l.) o. kuntze].abiotic stress possesses serious threat to plant distribution and production. in response to stress, plants induce the expression of many genes that function to protect the cellular machinery from stress-induced damages. these genes are largely regulated by specific transcription factors (tfs). nac family proteins are plant specific tfs implicated in diverse processes including development, and biotic and abiotic stress responses. the present work described (i) cloning of csnam-like protein gene ...201222543018
determination of catechins and flavonol glycosides in chinese tea varieties.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 compositi ...201226434273
pyridine metabolism in tea plants: salvage, conjugate formation and catabolism.pyridine compounds, including nicotinic acid and nicotinamide, are key metabolites of both the salvage pathway for nad and the biosynthesis of related secondary compounds. we examined the in situ metabolic fate of [carbonyl-(14)c]nicotinamide, [2-(14)c]nicotinic acid and [carboxyl-(14)c]nicotinic acid riboside in tissue segments of tea (camellia sinensis) plants, and determined the activity of enzymes involved in pyridine metabolism in protein extracts from young tea leaves. exogenously supplied ...201222527843
a review of phytotherapy of acne vulgaris: perspective of new pharmacological treatments.this review focuses on plants currently used and those with a high potency for the future development of anti-acne products.201222521501
effects of (-)-epigallocatechin gallate on the motility and penetrability of frozen-thawed boar spermatozoa incubated in the fertilization medium.epigallocatechin gallate (egcg) is the major polyphenol in green tea (camellia sinensis) and is known for its antioxidant effects. the objective of the present study was to examine the effects of egcg during in vitro fertilization (ivf) on the sperm quality and penetrability into oocytes. in the first experiment, the effects of concentration and incubation period of egcg on the motility and penetrability of spermatozoa were examined. when frozen-thawed spermatozoa were incubated in ivf medium su ...201222299777
isolation and identification of spermidine derivatives in tea (camellia sinensis) flowers and their distribution in floral organs.recently, tea (camellia sinensis) flowers have attracted increasing interest because of their content of bioactive compounds such as catechins. the aim of this study was to investigate the occurrence of some characteristic compounds in tea flowers.201222298050
post desiccation germination of mature seeds of tea (camellia sinensis l.) can be enhanced by pro-oxidant treatment, but partial desiccation tolerance does not ensure survival at -20°c.the maximal potential desiccation tolerance (mpdt) of tea (camellia sinensis) seeds has been a matter of debate for decades. here we assessed the ability of tea seeds from three sites in china to germinate after desiccation. desiccation tolerance was greatest in kunming, followed by puer and lincang, with kunming seeds tolerating drying to 8% moisture content (mc), or ∼0.5 water activity (a(w)). such tolerance was observed in lincang seeds only when hydrogen peroxide (h₂o₂) at 0.5 or 1m was appl ...201222284708
simultaneous determination of polyphenols and major purine alkaloids in greek sideritis species, herbal extracts, green tea, black tea, and coffee by high-performance liquid chromatography-diode array detection.herein, a high-performance liquid chromatography-diode array detection method has been developed for the simultaneous determination of 15 phenolic antioxidants: flavan-3-ols, (-)-epigallocatechin, (+)-catechin, (-)-epigallocatechin gallate, (-)-epicatechin, (-)-epicatechin gallate, (-)-gallocatechin, a phenolic acid (gallic acid), a hydroxycinnamic acid (chlorogenic acid), flavones (apigenin), flavonols (kaempferol, quercetin, and myricetin), and purine alkaloids (caffeine theophylline, theobrom ...201222282422
development of a methodology using gas chromatography-combustion-isotope ratio mass spectrometry for the determination of the carbon isotope ratio of caffeine extracted from tea leaves (camellia sinensis).compound-specific isotope analysis (csia) of the extracted caffeine can be used to determine the authenticity of the origin of tea. elemental analysis-isotope ratio mass spectrometry (ea-irms), which is widely used to measure the carbon isotope ratio of caffeine, has a strict requirement for the purity of the extracted caffeine. to obtain high-purity caffeine from tea leaves, the conventional extraction process has to be repeated and usually takes about 5-6 h. to improve the measurement of the c ...201222396035
green tea (camelia sinensis) mediated suppression of ige production by peripheral blood mononuclear cells of allergic asthmatic humans.recent studies in our laboratory demonstrated the suppression of immunoglobulin e (ige) production by green tea extract (gte) in u266 cells. however, the effects of gte or one of its components (egcg) on ige production by human peripheral blood mononuclear cells (pbmc) are unknown. pbmc (1.5 × 10⁶) obtained from serum ige+, allergic asthmatic patients, were cultured ± gte (1-100 ng/ml) or purified egcg (0.5-50 ng/ml), and ige levels were determined on day 10 by enzyme-linked immunosorbent assay ...201222670643
effects of black tea on blood pressure: a randomized controlled trial. 201222271130
turbidimetric and photometric determination of total tannins in tea using a micro-flow-batch analyzer.both turbidimetric and photometric determinations of total tannins in samples of green and black tea, using a micro-flow-batch analyzer (μfba) were studied. the miniaturized system was formed using photocurable urethane-acrylate resin and ultraviolet lithography technique. the turbidimetric method was based on the precipitation reaction of cu (ii) with tannins in acetate medium at a ph of 4.5. the photometric method was based on the complexation reaction of tannins with ferrous tartrate. the tur ...201222265564
polyphenolic content and comparative antioxidant capacity of flavoured black teas.the content of selected flavonoids and phenolic acids of 12 commercial flavoured black tea infusions was determined by high-performance liquid chromatography with tandem mass spectrometry in the negative electrospray ionization mode. assays for the evaluation of their antioxidant capacity were carried out by cupric ion reducing antioxidant capacity, folin-ciocalteu assay, cyclic voltammetry and potentiometry. flavonoids were predominantly present as glycosides in the studied infusions. only quer ...201222260547
reduction of matrix effects in liquid chromatography-electrospray ionization-mass spectrometry by dilution of the sample extracts: how much dilution is needed?in this study, the relationship between matrix concentration and suppression of electrospray ionization (matrix effects) was investigated. ion suppression of pesticides present in quechers extracts was used as an example. residue-free extracts of four different commodities, avocado, black tea, orange, and rocket (arugula), were fortified with 39 pesticides each. for many of the resulting 156 pesticide/matrix combinations, considerable matrix effects were observed if the coextracted matrix of 8 m ...201222243135
potential role of green tea catechins in various disease therapies: progress and promise.green tea (from the plant camellia sinensis), a beverage whose consumption started 5000 years ago in china, has important biological and pharmacological properties. the beneficial effects of green tea have been attributed to the presence of phenolic compounds that are powerful anti-oxidants and free iron scavengers. of all the catechins found in green tea, namely (-)-epicatechin-3-gallate, (-)-epigallocatechin, (-)-epicatechin and (-)-epigallocatechin-3-gallate (egcg), egcg is the most abundant ...201222229384
cardiovascular effects of black tea and nicotine alone or in combination against experimental induced heart injury.the present study was designed to elucidate the outcome of subchronic co-administration of black tea and nicotine on cardiovascular performance and whether these substances could modulate the isoproterenol-induced cardiac injury. animal groups were control, black tea, nicotine and black tea plus nicotine. test groups received nicotine (2 mg/kg s.c.) and black tea brewed (p.o.) each alone and in combination for 4 weeks. on the 28th day, myocardial damage was induced by isoproterenol (50 mg/kg i.p ...201222228381
molecular regulation of catechins biosynthesis in tea [camellia sinensis (l.) o. kuntze].catechins are bioprospecting molecules present in tea and any effort towards metabolic engineering of this important moiety would require knowledge on gene regulation. these are synthesized through the activities of phenylpropanoid and flavonoid pathways. expression regulation of various genes of these pathways namely phenylalanine ammonia-lyase (cspal), cinnamate 4-hydroxylase (csc4h), p-coumarate:coa ligase (cs4cl), flavanone 3-hydroxylase (csf3h), dihydroflavonol 4-reductase (csdfr) and antho ...201222226811
black tea (camellia sinensis) decoction shows immunomodulatory properties on an experimental animal model and in human peripheral mononuclear cells.black tea (camellia sinensis) has been used as a daily beverage for time immemorial. immunomodulatory effects of tea are recognized as it stimulates the proliferation of cultured human peripheral blood mononuclear cells. anti-inflammatory effects of tea have also been depicted in the available literature. therefore, we designed this study to examine the potential immunemodulatory and anti-inflammatory activities of black tea in a rat model and in human peripheral mononuclear cells.201222224056
magnesium nutrition on accumulation and transport of amino acids in tea plants.free amino acids in young tea shoots are important chemical constituents, remarkably influencing the quality of green teas. nutrient solution, soil pot and field experiments were conducted to investigate the effect of magnesium nutritional status on accumulation and transport of free amino acids in tea plants (camellia sinensis (l.) o. kuntze).201222083631
differential gene expression in tea (camellia sinensis l.) calli with different morphologies and catechin contents.tea (camellia sinensis) is a commercially important crop that contains valuable secondary metabolites. to understand the molecular regulation of secondary metabolism in tea, we selected and analyzed two cell lines of tea callus (yunjing63y and yunjing63x) that showed different morphological characteristics and catechin contents. yunjing63y callus was yellow and tight, while yunjing63x callus was white and loose. hplc analyses showed that yunjing63y contained 3.71 times higher levels of catechins ...201222078995
epicatechin-3-o-(3″-o-methyl)-gallate content in various tea cultivars (camellia sinensis l.) and its in vitro inhibitory effect on histamine release.it has been reported that epigallocatechin-3-o-(3″-o-methyl)-gallate (egcg3″me) and the egcg3″me-rich green tea ( camellia sinensis l.) cultivar 'benifuuki' exhibit antiallergic effects. the objective of this study was to investigate the effect of various tea leaf catechins on histamine release from murine bone marrow mast cells (bmmc). at a dose of 50 μg/ml, the rank order of histamine release inhibition was observed to be epicatechin-3-o-(3″-o-methyl)-gallate (ecg3″me) > gallocatechin-3-o-(3″- ...201222339247
an improved protocol for the isolation of rna from roots of tea (camellia sinensis (l.) o. kuntze).tea, a beverage crop, is a rich source of polyphenols and polysaccharides which greatly attribute to its importance. however, oxidation and precipitation of these compounds during nucleic acids extraction is a limitation to molecular biology and genomic studies. on isolation of total rna from root tissue using established protocols, difficulties were encountered in terms of purity and quantity of isolated rna or some of the methods were time-consuming and also yields were low. the present commun ...201222144070
characterization of l-phenylalanine metabolism to acetophenone and 1-phenylethanol in the flowers of camellia sinensis using stable isotope labeling.acetophenone (ap) and 1-phenylethanol (1pe) are the two major endogenous volatile compounds in flowers of camellia sinensis var. yabukita. until now no information has been available on the biosynthesis of ap and 1pe in plants. here we propose that ap and 1pe are derived from l-phenylalanine (l-phe), based on feeding experiments using stable isotope-labeled precursors l-[(2)h(8)]phe and l-[(13)c(9)]phe. the subacid conditions in the flowers result in more hydrogenation than dehydrogenation in th ...201222209218
ameliorative effect of black tea on nicotine induced cardiovascular pathogenesis in rat.regarding the role of nicotine in the development of cardiovascular complications of smoking, we investigated whether black tea has a modulatory effect on cardiovascular pathogenesis of nicotine in rat. animals were randomized to control, tea, nicotine and tea plus nicotine groups. test groups received black tea brewed (adding 400 ml boiling water to 10 g lipton black tea for 5 min) orally alone or with nicotine 2 mg/kg/day, s.c. separately or combined for four weeks. on 28th day, lipids profile ...201227418907
oxalate content of different drinkable dilutions of tea infusions after different brewing times.the aims of this study were to determine the effect of different brewing times and diluting on oxalate content of loose-packed black teas consumed in tabriz, iran.201224688937
aminobenzenesulfonamide functionalized sba-15 nanoporous molecular sieve: a new and promising adsorbent for preconcentration of lead and copper ions.a rapid method for the extraction and monitoring of nanogram level of pb2+ and cu2+ ions using uniform silanized mesopor (sba-15) functionalized with aminobenzenesulfonamide groups and flame atomic absorption spectrometry (faas) is presented. aminobenzenesulfonamide functionalized sba-15 was synthesized according to procedure in the literature and the presence of organic groups in the silica framework was demonstrated by ft-ir spectra. the functionalized product showed the bet surface area 110 m ...201223513457
analysis of camellia sinensis green and black teas via ultra high performance liquid chromatography assisted by liquid-liquid partition and two-dimensional liquid chromatography (size exclusion × reversed phase).green and black teas (camellia sinensis) contain compounds ranging from simple phenolics to complex glycosides, many of which have well-recognized health benefits. here, we describe two methodologies aiming to achieve a comprehensive analysis of hydro-alcoholic extracts of c. sinensis. in the first step, the extracts were partitioned in water, n-butanol, ethyl acetate and chloroform to separate the compounds according to their polarity, yielding less complex samples to be analyzed by ultra high ...201222204932
operation 'p53 hunt' to combat cancer: theaflavins in action.with phytochemicals executing a plethora of anti-tumor mechanisms, targeting the 'guardian angel' p53 appears to be a critical strategy to energize the process of cancer therapeutics. regulation of anti-tumor p53 functions by dietary plant polyphenols particularly black tea and its active component theaflavins has gained immense recognition from the point of view of both efficacy and safety. this review highlights the complexities of p53 functions, molecular mechanisms of its inactivation in can ...201222202062
the effect of black tea on risk factors of cardiovascular disease in a normal population.a prospective randomized controlled clinical trial determined the effect of mauritian black tea consumption on fasting blood plasma levels of glucose, lipid profiles and antioxidant status in a normal population.201222198621
adsorption kinetics of rhodamine-b on used black tea leaves.rhodamine b (rh-b) is one of the most common pollutants in the effluents of textile industries effluents in developing countries. this study was carried out to evaluate the applicability of used black tea leaves (ubtl) for the adsorptive removal of rh-b from aqueous system by investigating the adsorption kinetics in batch process. the effects of concentration and temperature on adsorption kinetics were examined. first-, second- and pseudo-second order kinetic equations were used to investigate t ...201223369452
determination of lead, cadmium and arsenic in infusion tea cultivated in north of iran.tea is one of the most common drinks in all over the world. rapid urbanization and industrialization in recent decades has increased heavy metals in tea and other foods. in this research, heavy metal contents such as lead (pb), cadmium (cd) and arsenic (as) were determined in 105 black tea samples cultivated in guilan and mazandaran provinces in north of iran and their tea infusions. the amount of heavy metals in black tea infusions were analyzed using inductively coupled plasma atomic emission ...201223369381
spatial distribution and management of isolated woody plants traditionally used as farmland boundary markers in ibaraki prefecture, japan.although noncrop woody plants in crop field landscapes serve multiple functions, the modernization of agriculture has threatened their preservation. in this study, isolated woody plants used as farmland boundary markers were investigated in ibaraki prefecture in the eastern kanto region. a total of 2001 individuals of 50 species were found around 177 equidistantly spaced points. the most frequently used species was deutzia crenata (60.7%), and the main subordinate species were pourthiaea villosa ...201223420389
electroantennogram responses of the tea slug moth, iragoides fasciata to some plant volatiles associated with tea, camellia sinensis.electroantennogram responses to a wide range of plant volatile compounds that have been identified in tea plants camellia sinensis l. (ericales: theaceae) were recorded from males and females of the tea slug moth, iragoides fasciata moore (lepidoptera: limacodidae). the responses to 26 compounds, belonging to several chemical classes, and two mixtures were evaluated. the results showed significantly different electroantennogram responses to the different chemicals, as well as significantly diffe ...201223414096
effect of electrolyzed reduced water on chiral theanine and polyphenols in tea.pure d/l-theanine enantiomers were synthesized separately, and sem was used for their crystal-structure observation. the novel enantiomeric separating method by hplc was established using the chiral selector of β-cd in the mobile phase. green tea, white tea, oolong tea, black tea and pu-erh tea were tested for theanine enantiomers by different degrees of fermentation. the significantly higher d-enantiomeric proportion of theanine was found in white tea than the others, which was probably due to ...201223442618
synergetic downregulation of 67 kda laminin receptor by the green tea (camellia sinensis) secondary plant compound epigallocatechin gallate: a new gateway in metastasis prevention?in traditional chinese medicine, green tea is considered to have a life-prolonging effect, possibly as a result of its rich content of antioxidant tea polyphenols, and hence has the potential to prevent cancer. this study investigated the role of the major tea secondary plant compound epigallocatechin gallate (egcg) for its inhibitory effects on the metastasis-associated 67 kda laminin receptor (67lr).201223249430
phosphorylation of hepatic amp-activated protein kinase and liver kinase b1 is increased after a single oral dose of green tea extract to mice.we have previously shown that green and black tea extracts increase the phosphorylation of amp-activated protein kinase (ampk) and hmg-coa reductase in rat hepatoma cells in culture, concomitant with a decrease in cholesterol synthesis. in the present study, we evaluated the ability of a single oral dose of green or black tea extract to promote the phosphorylation of ampk, liver kinase b1 (lkb1, an ampk-kinase), and hmg-coa reductase in mouse liver. green tea extract administered by gavage at 50 ...201223244544
nitric oxide participates in cold-inhibited camellia sinensis pollen germination and tube growth partly via cgmp in vitro.nitric oxide (no) plays essential roles in many biotic and abiotic stresses in plant development procedures, including pollen tube growth. here, effects of no on cold stress inhibited pollen germination and tube growth in camellia sinensis were investigated in vitro. the no production, no synthase (nos)-like activity, cgmp content and proline (pro) accumulation upon treatment with no scavenger cptio, nos inhibitor l-nna, no donor dea nonoate, guanylate cyclase (gc) inhibitor odq or phosphodieste ...201223272244
nutritional status assessment of minodar residence in qazvin city, iran: vitamin d deficiency in sunshine country, a public health issue.nutrition has main effect on health or disease and results of nutrition assessment can be used in health planning of communities. therefore we aimed to conduct the nutrition assessment especially vitamin d statue of an urban region in qazvin city.201223283050
the effect of camellia sinensis (green tea) mouthwash on plaque-induced gingivitis: a single-blinded randomized controlled clinical trial.background and the purpose of the studycomplementary medicine received high attention during last decades. we aimed to assess the efficacy of green tea mouthwash on plaque-induced gingivitis as the most common form of periodontal disease.201223351842
effect of beverages on bovine dental enamel subjected to erosive challenge with hydrochloric acid.this study evaluated by an in vitro model the effect of beverages on dental enamel previously subjected to erosive challenge with hydrochloric acid. the factor under study was the type of beverage, in five levels: sprite® zero low-calorie soda lime (positive control), parmalat® ultra high temperature (uht) milk, ades® original soymilk, leão® ice tea zero ready-to-drink low-calorie peach-flavored black teaand prata® natural mineral water (negative control). seventy-five bovine enamel specimens we ...201223207851
tea creaming in nonfermented teas from camellia sinensis and ilex vomitoria.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. ...201223148671
effects of saponin extracts on air emissions from steers.a series of experiments were conducted to quantify the effects of saponin extracts from quillaja saponaria molina (qs), yucca schidigera roezl ex ortgies (ys), and camellia sinensis (l.) kuntze (ts) on gaseous emissions from steers (bos taurus). during exp. 1, a control diet [c1, corn (zea mays l.) and corn silage basal diet] was compared with ys1 (c1 + 0.64% dietary dm of ys) and qs1 (c1 + 1.5% dietary dm of qs), with 4 replicates per treatment. during exp. 2, the control diet (c2, corn and cor ...201222665675
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