Publications

antiproliferative and apoptosis inducing effect of lactoferrin and black tea polyphenol combination on hamster buccal pouch carcinogenesis.	combination chemoprevention using tea polyphenols as one of the components has received growing consideration in recent years. the present study was designed to evaluate the antiproliferative and apoptosis inducing effects of bovine lactoferrin (blf) and black tea polyphenol (polyphenon-b: p-b) combination on 7,12-dimethylbenz[a]anthracene (dmba)-induced hamster buccal pouch (hbp) carcinogenesis. topical application of dmba for 14 weeks induced buccal pouch tumours that showed aberrant expressio ...	2006	16905260
correlation between the in vitro antioxidant activity and polyphenol content of aqueous extracts from bulgarian herbs.	the water phase antioxidant activity of extracts from 23 bulgarian medicinal plants was studied in relation to their polyphenol content in comparison with mate, black tea, honeybush and rooibos foreign species. antioxidant activity was measured by the abts (2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid)) cation radical decolorization assay, and the total polyphenol content was assayed according to the folin-ciocalteu method. five bulgarian plant extracts exhibited higher antioxidant activ ...	2006	16906640
metabonomics approach to determine metabolic differences between green tea and black tea consumption.	the purpose of this study was to compare the effects of black and green tea consumption on human metabolism. seventeen healthy male volunteers consumed black tea, green tea, or caffeine in a randomized crossover study. twenty-four-hour urine and blood plasma samples were analyzed by nmr-based metabonomics, that is, high-resolution 1h nmr metabolic profiling combined with multivariate statistics. green and black tea consumption resulted in similar increases in urinary excretion of hippuric acid a ...	2006	16939360
determination of trace elements in herbal tea products and their infusions consumed in thailand.	nineteen elements, mg, al, ca, v, cr, mn, fe, co, ni, cu, zn, se, sr, sb, ba, as, cd, hg, and pb, were determined in three types of popular herbal tea products, gynostemma pentaphyllum, camellia sinensis, and morus alba. these herbal tea products, both imported and locally made products, are widely consumed in thailand and worldwide. microwave-assisted acid digestion was used for all of the samples, and the element contents were determined by icp-ms. the concentrations of all elements varied amo ...	2006	16939361
a comparative study on the antimutagenic properties of aqueous extracts of aspalathus linearis (rooibos), different cyclopia spp. (honeybush) and camellia sinensis teas.	antimutagenic activity of aqueous extracts of the south african herbal teas, aspalathus linearis (rooibos) and cyclopia spp. (honeybush) was compared with that of camellia sinensis (black, oolong and green) teas in the salmonella mutagenicity assay using aflatoxin b(1) (afb(1)) and 2-acetylaminofluorene (2-aaf) as mutagens. the present study presents the first investigation on antimutagenic properties of c. subternata, c. genistoides and c. sessiliflora. the herbal teas demonstrated protection a ...	2006	16949333
differentially expression of tua1, a tubulin-encoding gene, during flowering of tea plant camellia sinensis (l.) o. kuntze using cdna amplified fragment length polymorphism technique.	the complementary dna (cdna) amplified fragment length polymorphism technique was used to isolate transcript-derived fragments corresponding to genes involved in the flowering of tea plant. comparative sequence analysis of an approximately 300 bp differential fragment amplified by primer combination e11m11 revealed 80%-84% similarity to the corresponding part of an a-tubulin gene of other species. the complete cdna sequence of this a-tubulin was cloned by the rapid amplification of cdna ends tec ...	2006	16953305
phenolic acids in berries, fruits, and beverages.	the contents of soluble and total phenolic acids were analyzed in samples of 29 berries and berry products, 24 fruits and fruit peels, and 12 beverages. variation of phenolic acids in berries was also studied. soluble phenolic acids were extracted with methanolic acetic acid, and a tentative quantification was performed by high-performance liquid chromatography (hplc). the total phenolic acid content was determined by hplc after alkaline and acid hydrolyses. the content of total phenolic acids a ...	2006	16968082
peracetylation as a means of enhancing in vitro bioactivity and bioavailability of epigallocatechin-3-gallate.	(-)-epigallocatechin-3-gallate (egcg) is the widely studied catechin in green tea (camellia sinensis). previously, we have reported the low bioavailability of egcg in rats and mice. as a means of improving the bioavailability of egcg, we have prepared a peracetylated egcg derivative (acegcg) and herein report its growth inhibitory activity and cellular uptake in vitro, as well as bioavailability in mice. acegcg exhibited enhanced growth inhibitory activity relative to egcg in both kyse150 human ...	2006	16997910
pro-oxidative effects of tea and polyphenols, epigallocatechin-3-gallate and epigallocatechin, on g6pd-deficient erythrocytes in vitro.	glucose-6-phosphate dehydrogenase (g6pd)-deficient subjects are vulnerable to chemical-induced hemolysis if exposed to oxidative agents. recent studies reported that green tea and its constituents might act as pro-oxidants. our objective was to investigate effects of tea and its polyphenolic components on the oxidative status of human g6pd-deficient erythrocytes. erythrocytes of g6pd-deficient (n = 8) and normal (n = 8) subjects were incubated with water extracts of 3 types of tea samples (black ...	2006	17016632
glucose-lowering effect of powder formulation of african black tea extract in kk-a(y)/tajcl diabetic mouse.	we observed the suppressive effect of a powder formulation of african black tea extract prepared from the leaves of camellia sinensis on type 2 non-insulin dependent diabetic mice, kk-a(y)/tajcl. black tea extract significantly showed suppressive effect of the elevation of blood glucose on oral glucose tolerance test of 8 week-old kk-a(y)/tajcl mice (p < 0.05). long-term treatment with black tea extract showed significant suppression of post-prandial blood glucose and obesity (p < 0.05). the wei ...	2006	17024853
[impact of green tea on oxidative stress induced by ammonium metavanadate exposure in male rats].	transitional metals, as vanadium, are known to exert noxious effects by generating oxidative stress. addition of antioxidants in the diet could decrease the cytotoxic effect related to the oxidative stress. the present study, carried out in wistar rats, is a contribution to the evaluation of protective effects of green tea camellia sinensis, which is known to be rich in antioxidant compounds (polyphenols...). rats were divided into four groups: (c) was control, (v) was given ammonium metavanadat ...	2006	17027638
in vivo and in vitro effects of tea extracts on enterotoxigenic escherichia coli-induced intestinal fluid loss in animal models.	enterotoxigenic escherichia coli (etec) infection is a major cause of dehydrating diarrhoea in infants and early-weaned piglets living under subhygienic conditions. we studied the effect of different tea types and subfractions on the intestinal fluid and electrolyte losses involved in etec diarrhoea.	2006	17033520
natural health products that inhibit angiogenesis: a potential source for investigational new agents to treat cancer-part 1.	an integrative approach for managing a patient with cancer should target the multiple biochemical and physiologic pathways that support tumour development and minimize normal-tissue toxicity. angiogenesis is a key process in the promotion of cancer. many natural health products that inhibit angiogenesis also manifest other anticancer activities. the present article focuses on products that have a high degree of anti-angiogenic activity, but it also describes some of the many other actions of the ...	2006	17576437
natural health products that inhibit angiogenesis: a potential source for investigational new agents to treat cancer-part 2.	the herbalist has access to hundreds of years of observational data on the anticancer activity of many herbs. laboratory studies are expanding the clinical knowledge that is already documented in traditional texts. the herbs that are traditionally used for anti-cancer treatment and that are anti-angiogenic through multiple interdependent processes (including effects on gene expression, signal processing, and enzyme activities) include artemisia annua (chinese wormwood), viscum album (european mi ...	2006	17576449
protective effect of black tea extract on the levels of lipid peroxidation and antioxidant enzymes in liver of mice with pesticide-induced liver injury.	sub-acute hepatotoxicity was induced in mice by exposure to pesticides. the effect of pretreatment with aqueous black tea extract on lipid peroxidation and antioxidants in the liver was investigated. administering a combination dose of chlorpyriphos and cypermethrin (20 mg kg(-1) each) on alternate days over a 15-day period to male mice resulted in induction of sub-acute toxicity as reflected by elevated levels of liver damage marker enzymes alkaline phosphatase(alp), aspartate transaminase(ast) ...	2006	15991261
cytotoxic and apoptogenic effect of tea (camellia sinensis var. assamica) root extract (tre) and two of its steroidal saponins ts1 and ts2 on human leukemic cell lines k562 and u937 and on cells of cml and all patients.	the anticancer activity of di- and tri-terpenes and other polyphenolic compounds present in tea is already reported. we evaluated the cytotoxic and apoptogenic effect of tea root extract (tre) and two of its steroidal saponins named as ts1 and ts2, on human cell lines and on cells from leukemic patients. it was found that tre, ts1 and ts2 significantly decreased cell count and that tre caused apoptosis, as confirmed morphologically by confocal microscopy and by flow-cytometric analysis using ann ...	2006	16197994
dose-dependent levels of epigallocatechin-3-gallate in human colon cancer cells and mouse plasma and tissues.	epigallocatechin-3-gallate (egcg; molecular formula: c22h18011)is the most abundant catechin in green tea (camellia sinensis theaceae). both egcg and green tea have been shown to have cancer-preventive activity in a number of animal models, and numerous mechanisms have been proposed based on studies with human cell lines. egcg has been shown to undergo extensive biotransformation to yield methylated and glucuronidated metabolites in mice, rats, and humans. in the present study, we determined the ...	2006	16204466
biosorption of heavy metals on aspergillus fumigatus immobilized diaion hp-2mg resin for their atomic absorption spectrometric determinations.	a solid phase extraction procedure based on biosorption of copper(ii), lead(ii), zinc(ii), iron(iii), nickel(ii) and cobalt(ii) ions on aspergillus fumigatus immobilized diaion hp-2mg has been investigated. the analytical conditions including amounts of a. fumigatus, eluent type, flow rates of sample and eluent solutions were examined. good recoveries were obtained to the spiked natural waters. the influences of the concomitant ions on the retentions of the analytes were also examined. the detec ...	2006	18970890
[thermostabilities of plant phenol oxidase and peroxidase, determining the technology of their use in food industry].	stabilities of phenol oxidase and peroxidase from tea plant (camellia sinensis l.) clone kolkhida leaves, apple (malus domestica l.) cultivar kekhura fruits, walnut (juglans regia l.) green pericarp, and horseradish (armoracia lapathifolia gilib) roots were studied using different storage temperature modes and storage duration. it was demonstrated that both enzymes retained residual activities (approximately 10%) upon 20-min incubation at 80 degrees c. phenol oxidases from tea, walnut, and, espe ...	2006	15859458
the screening analysis of antiradical activity of some plant extracts.	there is a need for screening studies in order to select plant extracts or plant raw materials with strong antiradical activity which could be used as medicines or substances to protect food from oxidation. in this paper the antiradical activities of some plant raw materials were investigated.	2006	17115006
[the roots of cha and gambir].	this article attempts to trace the origin of tea. the author believes the ancient chinese tea, "chia", is either jicha (water extract from the pith of acacia catechu that grows naturally in the mountainous border between the yunnan province of china and southern asian countries) or jicha-kagikazura (water extract from the young branches and leaves of uncaris gambir, originally found in india/sri lanka). both were pulverized after being kiln-dried and then mixed with water to produce a thick susp ...	2005	17152831
antioxidant activity of various teas against free radicals and ldl oxidation.	tea is a widely consumed beverage throughout the world. we assessed the antioxidant activity of six teas, including the aqueous extracts of green tea and oolong tea (camellia sinensis), tochu (eucommia ulmoides), gymnema sylvestre, japanese mugwort (artemisia princeps), and barley (hordeum vulgare), against 1,1-diphenyl-2-picrylhydrazyl (dpph) radicals and ldl oxidation, and examined the association of ldl oxidizability with the plasma catechin levels in 10 healthy volunteers with a single dose ...	2005	16296404
antimicrobial properties of green tea catechins.	extracts of leaves from the tea plant camellia sinensis contain polyphenolic components with activity against a wide spectrum of microbes. studies conducted over the last 20 years have shown that the green tea polyphenolic catechins, in particular (-)-epigallocatechin gallate (egcg) and (-)-epicatechin gallate (ecg), can inhibit the growth of a wide range of gram-positive and gram-negative bacterial species with moderate potency. evidence is emerging that these molecules may be useful in the con ...	2005	19844590
keemun black tea extract contains potent fatty acid synthase inhibitors and reduces food intake and body weight of rats via oral administration.	the inhibitory effects of a black tea extract on fatty acid synthase were measured through inhibition kinetics. the keemun black tea extract showed more potent inhibitory activity on fatty acid synthase than green tea extract. additionally, the inhibitory ability of the black tea extract depended on the extracting solvent and the conditions used. only 10-23% of the inhibitory activity from the black tea was extracted by the general method of boiling with water. the results suggested that the mai ...	2005	16206829
hepatoprotective effect of green tea (camellia sinensis) extract against tamoxifen-induced liver injury in rats.	tamoxifen citrate (tam), is widely used for treatment of breast cancer. it showed a degree of hepatic carcinogenesis. the purpose of this study was to elucidate the antioxidant capacity of green tea (camellia sinensis) extract (gte) against tam-induced liver injury. a model of liver injury in female rats was done by intraperitoneal injection of tam in a dose of 45mg kg(-1) day(-1), i.p. for 7 successive days. gte in the concentration of 1.5 %, was orally administered 4 days prior and 14 days aft ...	2005	16202236
camellia sinensis: historical perspectives and future prospects.	as the source of brewed tea preparations, camellia sinensis has operated for centuries at the interface of agriculture, politics, and biology. the purpose of this review is to present an inter-disciplinary survey of issues surrounding cultivation, processing, and consumption of the tea plant. particular attention is given to the biologic effects of tea: first, assessing at the level of human physiology its value as a chemopreventive and chemotherapeutic agent; second, examining effects of produc ...	2005	16236672
flavor characteristics of lapsang souchong and smoked lapsang souchong, a special chinese black tea with pine smoking process.	the major volatile constituents of lapsang souchong, smoked lapsang souchong, and smoked souchong, a group of special black teas in china, were analyzed with gc and gc-ms analyses. forty-nine constituents were identified. longifolene and alpha-terpineol were the most abundant compounds in the aroma. due to its special production process, the compounds longifolene, longicyclene, guaiacol, 4-methylguaiacol, 4-ethylguaiacol, etc., were identified only in this kind of black tea. the aroma constituen ...	2005	16248572
induction of apoptosis in human leukemia cells by black tea and its polyphenol theaflavin.	treatment of human leukemic cell lines hl-60 and k-562 with extracts of green and black tea and their polyphenols epigallocatechin gallate and theaflavins, respectively, showed a dose dependent inhibition of growth as a result of cytotoxicity and suppression of cell proliferation. based on the ic50 values obtained from cytotoxicity data it was clearly evident that black tea was as efficient as green tea. analysis of polyphenol contents of tea extracts revealed that not only epigallocatechin gall ...	2005	16253767
[rapd analysis on genetic diversity of the preconcentrated core germplasms of camellia sinensis in china].	the study was to evaluate the genetic diversity of 69 tea cultivars of the preconcentrated core germplasms of camellia sinensis in china by the random amplified polymorphic dna (rapd). among 50 arbitrary primers, 32 primers could generate enough amplified bands for all the strains in this study. among a total of 348 bands observed, 328 (94.3%)bands were polymorphic in the 69 cultivars tested except additional 20 cultivars. genetic distances between the cultivars varied from 0.223 to 0.723. the s ...	2005	16257906
oral administration of a decaffeinated green tea (camellia sinensis) extract did not alter urinary 8-epi-prostaglandin f(2 alpha), a biomarker for in-vivo lipid peroxidation.	oxidative stress is involved in the pathogenesis of numerous chronic human diseases. the objective of this study was to determine whether administration of a decaffeinated green tea extract providing 844 mg flavonoids daily reduced the urinary excretion of 8-epi-prostaglandin f(2 alpha) (8-epi-pgf(2 alpha)), a product of lipid peroxidation in cellular membranes and of low-density lipoprotein (ldl). nine healthy male and female subjects were studied at baseline and after 14 days of green tea supp ...	2005	16259767
in vitro and in vivo antimicrobial action of tea: the commonest beverage of asia.	the methanolic extract of leaves of camellia sinensis (l) o. kuntze was screened for antimicrobial property against 111 bacteria comprising 2 genera of gram positive and 7 genera of gram negative bacteria. most of these strains were inhibited by the compound at 10-50 microg/ml level and few strains were sensitive even at lower concentrations (5 microg/ml). the bacteria could be arranged in the decreasing order of sensitivity towards the compound in the following manner: staphylococcus aureus, vi ...	2005	16272702
ameliorative effects of black tea extract on aflatoxin-induced lipid peroxidation in the liver of mice.	we have evaluated the ameliorative effect of black tea extract on aflatoxin-induced lipid peroxidation in the liver of mice. adult male albino mice were orally administered with 25 and 50 microg of aflatoxin in 0.2 ml olive oil/animal/day for 30 days. results revealed dose-dependent and significantly (p<0.05) higher lipid peroxidation in the liver of aflatoxin-treated mice than that of vehicle control. as compared with vehicle control, the levels of non-enzymatic antioxidants such as glutathione ...	2005	15582201
dissipation behavior of propargite--an acaricide residues in soil, apple (malus pumila) and tea (camellia sinensis).	propargite, recently introduced in india, is an effective acaricide on a large number of crops most of which are consumed by human beings directly or after processing. therefore, it has become important to check the dissipation behavior of propargite in edible raw commodities, processed products and in the environment. in the present study, dissipation of residue of this acaricide in soil, apple fruit and tea (green tea leaves, manufactured tea, infusion and spent leaves) was studied. analysis w ...	2005	15621197
anti-inflammatory activity of indian black tea (sikkim variety).	in this study, the anti-inflammatory (in reference to the cardinal signs of inflammation) and other related pharmacological activities of the hot water extract of black tea (camellia sinensis, sikkim variety) were evaluated along with certain standard drugs. the extract showed significant inhibitory activity against carrageenin, histamine, serotonin and prostaglandin-induced pedal inflammation. the extract inhibited exudative inflammation. the tea extract also inhibited cotton pellet-induced gra ...	2005	15629264
variations of main quality components of tea genetic resources [camellia sinensis (l.) o. kuntze] preserved in the china national germplasm tea repository.	the variations of the main quality components of tea, tea polyphenols, catechins, amino acids, caffeine, and water extract of 596 accessions chinese tea genetic resources, preserved in the china national germplasm tea repository (cngtr), were analyzed. tea polyphenols content on a dry weight basis varied from 13.6 to 47.8%, averaging 28.4%. the tea polyphenols content increases gradually from northern and eastern provinces to southern provinces, the highest is in yunnan tea resources. the conten ...	2005	15898357
black tea polyphenols suppress cell proliferation and induce apoptosis during benzo(a)pyrene-induced lung carcinogenesis.	one of the most promising strategies for cancer prevention is chemoprevention by daily used food and beverages. black tea, the most widely consumed beverage, is a source of compounds with antioxidative, antimicrobial, antimutagenic and anticarcinogenic properties. lung cancer is the most common cause of cancer deaths in both men and women worldwide. over one million people around the world are likely to be killed by lung cancer due to increased tobacco smoking and environmental pollutants, espec ...	2005	15901989
black tea theaflavins suppress dioxin-induced transformation of the aryl hydrocarbon receptor.	dioxins cause various adverse effects through transformation of aryl hydrocarbon receptor (ahr). in this study, we investigated whether black tea extract and its components, theaflavins, suppress ahr transformation in vitro. first, we confirmed that black tea extract strongly suppressed ahr transformation compared to green and oolong tea, although the catechin contents did not change significantly among the extracts. then we isolated four theaflavins as active compounds from black tea leaves. th ...	2005	15914905
determination of some organochlorine compounds in herbal colouring agent henna (lawsonia inermis) and in tea (thea sinensis).	henna (lawsonia inermis) has been used for centuries as a herbal hair and skin dye, but very little is known about its additives and contaminants that could adversely affect human health. an analytical method was developed to determine organochlorine compounds in henna, as they are still widely used in the areas where henna is grown. samples were sonicated with n-hexane, extracts cleansed on florisil sorbent and analysed using gas chromatography with electron capture detection. the overall recov ...	2005	15969202
molecular definition of black tea taste by means of quantitative studies, taste reconstitution, and omission experiments.	recently, bioresponse-guided fractionation of black tea infusions indicated that neither the high molecular weight thearubigens nor the theaflavins, but a series of 14 flavon-3-ol glycopyranosides besides some catechins, might be important contributors to black tea taste. to further bridge the gap between pure structural chemistry and human taste perception, in the present investigation 51 putative taste compounds have been quantified in a black tea infusion, and their dose-over-threshold (dot) ...	2005	15969522
phytoestrogenic effects of black tea extract (camellia sinensis) in an oophorectomized rat (rattus norvegicus) model of osteoporosis.	the adverse side effects of currently available anti-osteoporotic agents warrant the search for compounds with less toxic effects. in this study, we assessed the phytoestrogenic potentiality of whole aqueous extract of black tea (bte) in a bilaterally oophorectomized rat model (2.5%, 1 ml/100 g body weight/day for 28 days). although the supplementation was given for 28 days but, sign of revival of copulation period (estrous stage) from non-receptive diestrous stage was first noticed after 21 day ...	2005	15996685
epigallocatechin gallate (egcg) (teavigo) does not impair nonhaem-iron absorption in man.	a number of studies have shown that tea catechins can inhibit intestinal iron absorption, mostly iron in the nonhaem form. this randomized, double-blind, placebo-controlled, 3-periods cross-over study examined the degree of inhibition of nonhaem iron absorption by pure crystalline epigallocatechin gallate (egcg). the study was designed to show the maximum inhibitory action of egcg by selecting 30 healthy women with low iron stores. treatments were 150 mg, 300 mg egcg and placebo each for 8 conse ...	2005	16008116
addition of milk does not alter the antioxidant activity of black tea.	tea is a polyphenol-rich beverage like wine and catechins are its chief polyphenols. catechins have cardio-protective effects as they can scavenge free radicals and inhibit lipid peroxidation. epidemiological studies indicate an inverse relation between tea consumption and the risk of cardiovascular and other chronic diseases. addition of milk to black tea has been reported to adversely affect its beneficial effects, but the data are not unequivocal. therefore, we assessed the effect of the addi ...	2005	16020939
cosmeceuticals containing herbs: fact, fiction, and future.	modern medicine is rooted in ethnobotanical traditions using indigenous flora to treat symptoms of human diseases or to improve specific aspects of the body condition. herbal medicine is now used by over half of the american population. yet the american medical community generally lacks knowledge of the function, metabolism, interaction, adverse reactions, and preparation of herbal products.	2005	16029681
use of black tea in modulating clastogenic effects of arsenic in mice in vivo.	the concentration of arsenic in drinking water has far exceeded the permissible limit of 0.001 mg/l and has reached epidemic proportions, with a maximum of 3.7 mg/l in several districts of west bengal and in the adjoining bangladesh. because inorganic arsenic is a documented human carcinogen, arsenic in drinking water may cause 200,000-270,000 deaths per year from cancer in india alone. tea has a protective effect against the clastogenicity of arsenic. we investigated whether tea extracts could ...	2005	16050804
black tea extract can modulate protein expression of h-ras, c-myc, p53, and bcl-2 genes during pulmonary hyperplasia, dysplasia, and carcinoma in situ.	lung cancer has emerged as one of the leading causes of cancer death in most developed and many developing countries of the world. in the absence of effective screening and early detection methods of lung cancer and overall poor prognosis, the 5-year survival following treatment has not improved significantly over the last two decades. it is hoped that the risk of the disease can be minimized by preventive measures. one aspect of lung cancer prevention emphasizes the cessation of tobacco smoking ...	2005	16050805
supplementation of waste tea fungal biomass as a dietary ingredient for broiler chicks.	the waste tea fungal biomass produced during black tea fermentation was investigated as a dietary ingredient in poultry feeds. a small portion of fungal mat was used as starter culture for the next cycle while the major portion is discarded as waste. hence a trial study was carried out to utilize the waste fungal biomass as a supplementary diet for broiler chicks. the fungal biomass contained 179.38 g of crude protein, 120 g crude fibre, 4.82 g phosphorus, 6.56 g of calcium and 8.92 mj metaboliz ...	2005	16051080
inhibitory effects of various beverages on ritodrine sulfation by recombinant human sulfotransferase isoforms sult1a1 and sult1a3.	ritodrine is known to undergo extensive presystemic sulfation in the intestinal mucosa, and its bioavailability is as low as 30%. accordingly, inhibition of intestinal sulfation may lead to an increase in the bioavailability of ritodrine. in this study, we aimed to investigate the activities of ritodrine sulfation by sult1a1, which is expressed predominantly in the liver, and sult1a3, which is expressed predominantly in the intestine, as well as the inhibitory effects of beverages on their activ ...	2005	16078151
synergistic antimicrobial activity of tea & antibiotics.	tea leaves are known for its antibacterial activity against many microorganisms. in this study we attempted to describe the synergistic antimicrobial activity of tea and antibiotics against enteropathogens. antimicrobial activity of boiled water tea extract and organic solvent extract were studied against salmonella typhimurium 1402/84, s. typhi, s. typhi ty2a, shigella dysenteriae, yersinia enterocolitica c770, and escherichia coli (epec p2 1265) determining minimum inhibitory concentration (mi ...	2005	16106094
protective effects of black tea extract on testosterone induced oxidative damage in prostate.	since ancient times, antipyretic, anti-inflammatory, antimicrobial and antioxidative properties of tea have been recognized. black tea (camellia sinensis) contains a variety of polyphenolic ingredients including the theaflavins (tf), thearubigins (tg) and catechins. components from black tea have been accounted to play an important role in scavenging free radicals generated by mutagens and carcinogens. androgens are the key factors in either the initiation or progression of prostate cancer (pca) ...	2005	16112415
hplc analysis of naturally occurring methylated catechins, 3' '- and 4' '-methyl-epigallocatechin gallate, in various fresh tea leaves and commercial teas and their potent inhibitory effects on inducible nitric oxide synthase in macrophages.	(-)-epigallocatechin-3-gallate (egcg), a major polyphenol of green tea, undergoes substantial biotransformation to species that includes the methylated compounds. recent studies have demonstrated that the methylated egcg has many biological activities. in this study, we have investigated the composition of the three o-methylated egcg derivatives, (-)-epigallocatechin-3-o-(3-o-methyl)gallate (3' '-me-egcg), (-)-epigallocatechin-3-o-(4-o-methyl)gallate (4' '-me-egcg) and (-)-4'-methyl epigallocate ...	2005	16131108
inhibitory effects of epigallocatechin gallate on compound 48/80-induced mast cell activation and passive cutaneous anaphylaxis.	epigallocatechin gallate (egcg) is a principle phenolic antioxidant found in a variety of plants, including green and black tea. the anti-allergic effect of egcg is unknown. the purpose of this study is to investigate the effects of egcg on compound 48/80-induced mast cell activation and passive cutaneous anaphylaxis. for this, the influences of egcg on the compound 48/80-induced cutaneous reaction were measured in vivo and the effects of egcg on the compound 48/80-induced mast cell activations ...	2005	16155406
novel treatments for obesity and osteoporosis: targeting apoptotic pathways in adipocytes.	obesity and osteoporosis have grave consequences for human health, quality of life, and even the efficiency of the labor force and economy. however, these pathologies share a common cell progenitor, revealing a surprising target for drug research and development. recent findings show that high adipocyte count in bone marrow is directly related to bone loss, as fat cells replace osteoblasts (or bone-forming cells). the objective of this review is to examine the importance of adipocyte apoptosis i ...	2005	16178781
effect of herbal polyphenols on atherogenic transcriptome.	the ancient indian system of medicine supports the antiatherogenic properties of some herbs. the crosstalk amongst the genes coding for ldlr, lxralpha, ppars (alpha,gamma), cd-36 and c-myc may be important in atherogenesis because these genes control lipid metabolism, cytokine production and cellular activity within the arterial wall. hence, we attempted for the first time to explore whether or not the polyphenols extracted from medicinal herbs had any effect on the transcription of these genes. ...	2005	16180103
floratheasaponins a-c, acylated oleanane-type triterpene oligoglycosides with anti-hyperlipidemic activities from flowers of the tea plant (camellia sinensis).	the methanolic extract and its n-butanol-soluble fraction from the flowers of the tea plant (camellia sinensis) were found to suppress serum triglyceride elevation in olive oil-treated mice. from the n-butanol-soluble fraction, three new acylated oleanane-type triterpene oligoglycosides, floratheasaponins a-c (1-3), were isolated together with several flavonol glycosides and catechins. the structures of 1-3 were elucidated on the basis of chemical and physicochemical evidence as 21-o-angeloyl-22 ...	2005	16180814
oxidative deamination of benzylamine and lysine residue in bovine serum albumin by green tea, black tea, and coffee.	oxidative deamination by various polyphenolic compounds is presumed to be due to the oxidative conversion of polyphenols to the corresponding quinones through autoxidation. here we examined the oxidative deamination by the polyphenol-rich beverages green tea, black tea, and coffee at a physiological ph and temperature. green tea, black tea, and coffee extracts oxidatively deaminated benzylamine and the lysine residues of bovine serum albumin to benzaldehyde and alpha-aminoadipic delta-semialdehy ...	2005	16190665
modulation of mpp+ uptake by tea and some of its components in caco-2 cells.	the entry of most xeno/endobiotics into the organism is limited by their intestinal absorption. the interference of certain foods with the therapeutic efficacy of drugs or with chemical toxicity is becoming evident and growing attention is being given to these subjects. the aim of this work was to study the effect of green tea (gt) and black tea (bt), as well as some of their components, on the transport of organic cation molecules. for this purpose, 3h-mpp+ (radiolabeled 1-methyl-4-phenylpyridi ...	2005	16193318
mediation of the in vitro cytotoxicity of green and black tea polyphenols by cobalt chloride.	the effects of co2+ (as cocl2) on the cytotoxicity of green tea polyphenol (gtp) and black tea polyphenol (btp) extracts towards proliferation of immortalized human gingival epithelial-like s-g cells were studied. the 24 h potencies of gtp and btp extracts, as determined with the neutral red (nr) cell viability assay, were greatly reduced in the presence of 250, but not of 50, microm co2+. the cytotoxicities of the gtp and btp extracts were due, in part, to their generation of hydrogen peroxide ...	2005	15585375
in vitro studies of baicalin alone or in combination with salvia miltiorrhiza extract as a potential anti-cancer agent.	traditional chinese herbal medicines (tcm) that for centuries have been used in disease prevention and treatment are finding use as alternatives to western cancer therapies. from a panel of tcm, we chose four compounds representing two functional classes of botanicals, the purified plant flavins scutellarin (a circulatory stimulant) and baicalin (antipyretic), and two extracts purified from salvia miltiorrhiza (sm-470, circulatory stimulant) and camellia sinensis (cam-300, antipyretic), and exam ...	2005	15586243
comparative studies on the hypolipidemic and growth suppressive effects of oolong, black, pu-erh, and green tea leaves in rats.	the four major commercial teas, oolong, black, pu-erh, and green teas, have been manufactured in southeast asia. in this study, we evaluated the growth suppressive and hypolipidemic effect of these four different tea leaves by oral feeding to male sprague-dawley rats for 30 weeks. the results showed that the suppression of body weights of tea leaves-fed groups were in the order: oolong tea > pu-erh tea > black tea > green tea. pu-erh tea and oolong tea could lower the levels of triglyceride more ...	2005	15656692
tea and circulating estrogen levels in postmenopausal chinese women in singapore.	the role of tea in the etiology of breast cancer is controversial. we recently provided the first set of human evidence that breast cancer risk is significantly inversely associated with tea intake, largely confined to intake of green tea. since black tea and green tea possess comparable levels of the total tea polyphenols that possess antioxidative activities, reasons for the paradoxical effects of green tea and black tea on breast cancer protection are not apparent. some limited evidence sugge ...	2005	15661801
paradoxical effects of green tea (camellia sinensis) and antioxidant vitamins in diabetic rats: improved retinopathy and renal mitochondrial defects but deterioration of collagen matrix glycoxidation and cross-linking.	we tested the hypothesis that green tea prevents diabetes-related tissue dysfunctions attributable to oxidation. diabetic rats were treated daily with tap water, vitamins c and e, or fresh japanese green tea extract. after 12 months, body weights were decreased, whereas glycated lysine in aorta, tendon, and plasma were increased by diabetes (p < 0.001) but unaffected by treatment. erythrocyte glutathione and plasma hydroperoxides were improved by the vitamins (p < 0.05) and green tea (p < 0.001) ...	2005	15677510
short-term administration of (-)-epigallocatechin gallate reduces hepatic steatosis and protects against warm hepatic ischemia/reperfusion injury in steatotic mice.	hepatic steatosis increases the extent of cellular injury incurred during ischemia/reperfusion (i/r) injury. (-)-epigallocatechin gallate (egcg), the major flavonoid component of green tea (camellia sinensis) is a potent antioxidant that inhibits fatty acid synthase (fas) in vitro. we investigated the effects of egcg on hepatic steatosis and markers of cellular damage at baseline and after i/r injury in ob/ob mice. animals were pretreated with 85 mg/kg egcg via intraperitoneal (ip) injection for ...	2005	15719408
inhibition of benzo[a]pyrene induced mutagenicity and genotoxicity by black tea polyphenols theaflavins and thearubigins in multiple test systems.	this study investigated the antimutagenic and anticlastogenic effects of black tea polyphenols, theaflavins (tf) and thearubigins (tr) in salmonella assay in vitro and in vivo in bone marrow cells of mice as measured by chromosomal aberrations (ca) and sister chromatid exchange (sce) against a known carcinogen, benzo[a]pyrene (b[a]p). a significant decrease in mutagenicity in salmonella assay and both ca and sce were observed in all the different concentrations of tf and tr plus b[a]p treated se ...	2005	15721207
genetic diversity of upasi tea clones (camellia sinensis (l.) o. kuntze) on the basis of total catechins and their fractions.	tea leaf catechins and the ratio of dihydroxylated to trihydroxylated catechin fractions were analysed to identify the genetic diversity of 26 upasi released tea clones. principal component analysis (pca) based on regression factor separated tea clones into five groups according to their jats (jats are region based rays for e.g., assam, china and cambod origin) as well as their quality constituents (such as total polyphenols, total catechins, amino acids in the green leaves and liquor characteri ...	2005	15721948
nuclear magnetic resonance spectroscopic based studies of the metabolism of black tea polyphenols in humans.	epidemiological studies indicate that a high intake of flavonoids is associated with an improved health status. tea is one of the most abundant sources of flavonoids in the human diet. the bioavailability and biotransformation of tea flavonoids are, however, not clearly understood. the aim of the present study was to investigate the metabolism of black tea via a nonspecific screening method. (1)h nuclear magnetic resonance (nmr) spectroscopy was used to obtain nonselective profiles of urine samp ...	2005	15740018
inhibition of lung tumorigenesis by tea.	tea and tea constituents have been shown by different investigators to inhibit lung tumorigenesis in different animal model systems. this includes lung tumorigenesis in a/j mice induced by 4-(methylnitrosamino)-1-(3pyridyl)-1-butanone (nnk), n-nitrosodiethylamine, benzo[a]pyrene, n-nitrosomethylurea, or cisplatin. inhibition of lung tumorigenesis has also been demonstrated in c3h mice treated with n-nitrosodiethylamine. in most of these experiments, reduction in tumor number and tumor size has b ...	2005	15765923
in vitro antimycotic activity of some plant extracts towards yeast and yeast-like strains.	as part of screening aimed at the selection of novel antimycotic compounds of vegetable origin, leaf extracts of camellia sinensis l., cupressus sempervirens l. and pistacia lentiscus l. and the seed extract of glycine soja sieb. et zucc. were tested against yeast and yeast-like species implicated in human mycoses. of the extracts only those of c. sinensis (obtained from a commercial preparation of green tea) exhibited broad activity towards candida glabrata, clavispora lusitatiae, cryptococcus ...	2005	15798996
green tea intake, ace gene polymorphism and breast cancer risk among chinese women in singapore.	experimental and epidemiological data have implicated a potential chemoprotective role of green tea polyphenols and a potential enhancing role of angiotensin ii in the development of breast cancer in humans. angiotensin ii is converted from its precursor by angiotensin-converting enzyme (ace). women with low-activity genotype of the ace gene had a reduced risk of breast cancer compared with those possessing high-activity ace genotype. experimental data showed that green tea polyphenols could inh ...	2005	15802301
effects of tea constituents on cell cycle progression of human leukemia u937 cells.	tea and tea constituents are known to induce apoptosis in a variety of cancerous cells, suggesting their beneficial effects as chemopreventive agents. previous studies have shown that low molecular weight constituent catechins and high molecular weight fractions of tea have the apoptosis-inducing activity, but that their action mechanisms may be different. since cell cycle arrest is known to be one of the underlying mechanisms of apoptosis, we examined the effects of these tea constituents on ce ...	2005	15806977
effect of certain bioactive plant extracts on clinical isolates of beta-lactamase producing methicillin resistant staphylococcus aureus.	ethanolic extracts and some fractions from 10 indian medicinal plants, known for antibacterial activity, were investigated for their ability to inhibit clinical isolates of beta-lactamase producing methicillin-resistant staphylococcus aureus (mrsa) and methicillin-sensitive s. aureus (mssa). synergistic interaction of plant extracts with certain antibiotics was also evaluated. the mrsa test strains were found to be multi-drug resistant and also exhibited high level of resistance to common beta-l ...	2005	15812867
theaflavin derivatives in black tea and catechin derivatives in green tea inhibit hiv-1 entry by targeting gp41.	theaflavin derivatives and catechin derivatives are the major polyphenols in black tea and green tea, respectively. several tea polyphenols, especially those with galloyl moiety, can inhibit hiv-1 replication with multiple mechanisms of action. here we showed that the theaflavin derivatives had more potent anti-hiv-1 activity than catechin derivatives. these tea polyphenols could inhibit hiv-1 entry into target cells by blocking hiv-1 envelope glycoprotein-mediated membrane fusion. the fusion in ...	2005	15823507
potent suppressive effect of green tea polyphenols on tobacco-induced mutagenicity.	antimutagenic activity of green tea (camellia sinensis) was studied using salmonella typhimurium strains (ta 102) (ames test). aqueous tobacco extract was found to be mutagenic to s. typhimurium ta 102 at concentration of 50 mg/plate. green tea polyphenols was found to inhibit the mutagenicity of tobacco in a concentration-dependent manner. concentrations needed for 50% inhibition of mutagen-induced revertant formation was found to be 5 mg/plate. green tea polyphenols was also found to inhibit t ...	2005	15830844
inhibitory effect(s) of polymeric black tea polyphenols on the formation of b(a)p-derived dna adducts in mouse skin.	the biological activities and chemopreventive properties of green tea polyphenols have been demonstrated, while similar information regarding newly formed major polymeric polyphenols in black tea are not available. cancer chemoprevention may be achieved by the inhibition of any stage of carcinogenesis. in the present study, we investigated the anti-initiating effects of five polymeric black tea polyphenol (pbp) fractions, by determining their effects on the formation of [3h]-b(a)p-derived dna ad ...	2005	15831081
black tea protects thymocytes in tumor-bearing animals by differential regulation of intracellular ros in tumor cells and thymocytes.	the accumulated in vitro evidence indicates that many tumors induce t-cell apoptosis as a mechanism of inhibiting antitumor activity. this downregulation of cell-mediated immune functions occurring at the late stages of the disease may be causally related to the thymic involution, because the thymus is the major site of t-cell maturation, extensive proliferation, and differentiation. our results showed that in erhlich's ascites carcinoma cell (eac)-bearing mice, the number of eac was inversely p ...	2005	15831082
antioxidant potential of black tea against 7,12-dimethylbenz(a)anthracene- induced oxidative stress in swiss albino mice.	oxygen free radicals and related reactive species have been implicated in the etiology of many diseases, such as atherosclerosis, neurodegenerative disorders, and cancer. antioxidant enzymes exist in cells to protect against the effects of these free radicals and other oxygen-derived species, which are produced during the oxidative stress. tea (camellia sinensis) is the most commonly consumed beverage worldwide. both green and black tea are known to possess many pharmacological properties, inclu ...	2005	15831083
black tea (camellia sinensis) as a chemopreventive agent in oral precancerous lesions.	oral carcinoma is the most common malignancy found in adult indian men and the third most common in adult indian women. about half of all cases are found to be associated with precancerous lesions, chiefly leukoplakia. we wanted to explore the possible benefits of black tea (camellia sinensis) administered to patients with oral leukoplakia. eighty-two subjects with oral leukoplakia underwent micronuclei and chromosomal assays on exfoliated oral mucosal epithelium, after which they received black ...	2005	15831086
the theaflavin fraction is responsible for the facilitatory effect of black tea at the skeletal myoneural junction.	the effect of various fractions of black tea [(camellia sinensis) (l) o. kuntze (theaceae)] on the function of mammalian skeletomotor apparatus was studied. the theaflavin fraction (tfs) produced a concentration- dependent facilitation of indirect twitch responses of the rat phrenic nerve diaphragm preparation and the facilitation was dependent on the amount of calcium present in the bathing fluid. nifedipine reduced the facilitatory effect of tfs as a function of its concentration. tfs failed t ...	2005	15850600
[relationship between plant community succession and fertility variation of mountain yellow soil in east chongqing].	based on the analyses of soil physical and chemical properties, this paper studied the relationship between plant community succession and fertility variation of mountain yellow soil in east chongqing. the results showed that the values of integrated soil fertility index of pinus massoniana, cunninghamia lanceolata, deciduous oak, camellia sinensis and evergreen broad-leaved forest soils were 0.1256, 0.2085, 0.3514, 0.2479 and 0.9329, respectively, implying that soil development had a close rela ...	2005	15852912
black and green teas equally inhibit diabetic cataracts in a streptozotocin-induced rat model of diabetes.	green and black teas were given at 1.25% in the drinking water to streptozotocin-induced diabetic rats for 3 months. normal and diabetic control groups were also studied. as expected, diabetic animals had significantly increased glucose in lens and plasma. lens and red blood cell sorbitol were significantly increased as a result of the aldose reductase pathway activation. plasma and lens lipid thiobarbituric acid-reactive substances and protein glycation were also significantly elevated. both te ...	2005	15853424
ilex paraguariensis extracts are potent inhibitors of nitrosative stress: a comparative study with green tea and wines using a protein nitration model and mammalian cell cytotoxicity.	due to the increasing importance of nitrosative stress in pathology and the efficacy displayed by flavonoids in cancelling the effects of peroxynitrite, we decided to conduct a comparative study of three commonly used beverages with the highest polyphenol contents and proven antioxidant properties: mate (ilex paraguariensis); green tea (camelia sinensis) extracts and white and red wines of the main varietals. we directly evaluated and compared the extracts and wines as protein nitration inhibito ...	2005	15878361
p38 mitogen-activated protein kinase activates enos in endothelial cells by an estrogen receptor alpha-dependent pathway in response to black tea polyphenols.	black tea has been shown to improve endothelial function in patients with coronary artery disease and recent data indicate the polyphenol fraction of black tea enhances endothelial nitric oxide synthase (enos) activity through p38 map kinase (p38 mapk) activation. because the mechanisms for this phenomenon are not yet clear, we sought to elucidate the signaling events in response to black tea polyphenols. bovine aortic endothelial cells (baecs) exposed to black tea polyphenols demonstrated enos ...	2005	15879307
pesticide-induced alteration in mice hepato-oxidative status and protective effects of black tea extract.	this study investigates the role of black tea extract in protection against oxidative damage induced in mice by a subacute oral dose of a combination of pesticides.	2005	15885683
differential display-mediated identification of three drought-responsive expressed sequence tags in tea [camellia sinensis (l.) o. kuntze].	there is no information on drought-modulated gene(s) in tea [camellia sinensis (l.) o. kuntze], a woody and perennial plant of commercial importance. using differential display of mrna, three drought-modulated expressed sequence tags (ests) were identified. northern and blast analysis revealed that clone dr1 (drought-responsive), induced only by drought but not by aba, showed significant scores with pr-5 (pathogenesis related) family of pr-protein gene. another clone dr2, repressed by drought bu ...	2005	15886459
heteroactivation of cytochrome p450 1a1 by teas and tea polyphenols.	we studied 7-ethoxyresorufin deethylase as an index of cytochrome p4501a1 (cyp1a1) activity in liver microsomes from rats pretreated with 3-methylcholanthrene. the enzyme had complex kinetics compatible with a multisite model. at 1 microm substrate, brewed black, green and white teas had complex effects on enzyme activity consisting of activation at low concentrations and inhibition at higher concentrations. data fit well to a two-site model that allowed us to determine maximal activation (% inc ...	2005	15895106
coq9 potentiates green tea antioxidant activities in wistar rats.	green tea (camellia sinensis), and coq(9 )when given to wistar rats produced a partial reversal on reserpine induced oxidative stress and liver damage. green tea, with its abundant polyphenol (-)epigallocatechin 3-gallate (ecgc) and other catechins, is known for its antioxidative characteristics influencing lipid metabolism. ubiquinone, abundant in heart muscle, is also a potent antioxidant with known effects in numerous pathologies. however the combined effect of ecgc and ubiquninone has not be ...	2005	16873954
bactericidal and anti-adhesive properties of culinary and medicinal plants against helicobacter pylori.	to investigate the bactericidal and anti-adhesive properties of 25 plants against helicobacter pylori (h. pylori).	2005	16437723
maximum residue limit and risk assessment of spiromesifen (bay bsn 2060; oberon 240sc) on tea (camellia sinensis (l) o' kuntze).		2005	16400559
effect of polymeric black tea polyphenols on benzo(a)pyrene [b(a)p]-induced cytochrome p4501a1 and 1a2 in mice.	the chemopreventive activity of green tea polyphenols (gtps) is, in part, due to modulation of cytochrome p450s (cyps). to investigate the enzyme modulatory properties of major black tea polyphenols, the effect of decaffeinated black tea extract (dbte) or polymeric black tea polyphenol (pbp) mix was studied on cyp1a1 and cyp1a2 in mouse tissues. animals receiving 2.5% dbte or 1% pbp mix or drinking water (15 days) were challenged with single oral benzo(a)pyrene (b(a)p) (1 mg/mouse) treatment on ...	2005	16316927
a clinical study: melaleuca, manuka, calendula and green tea mouth rinse.	a novel mouthrinse (ind 61,164) containing essential oils and extracts from four plant species (melaleuca alternifolia, leptospermum scoparium, calendula officinalis and camellia sinensis) were tested. this study aimed to evaluate the safety, palatability and preliminary efficacy of the rinse. fifteen subjects completed the phase i safety study. seventeen subjects completed the phase ii randomized placebo-controlled study. plaque was collected, gingival and plaque indices were recorded (baseline ...	2005	16317652
bioactive saponins and glycosides. xxiii. triterpene saponins with gastroprotective effect from the seeds of camellia sinensis--theasaponins e3, e4, e5, e6, and e7.	the saponin fraction from the seeds of the tea plant [camellia sinensis (l.) o. kuntze (theaceae)] was found to exhibit potent protective effects on ethanol- and indomethacin-induced gastric mucosal lesions in rats. five new triterpene saponins, theasaponins e3 (1), e4 (2), e5 (3), e6 (4), and e7 (5), were isolated together with 11 known saponins from the saponin fraction. the chemical structures of 1-5 were elucidated on the basis of chemical and physicochemical evidence. among the isolated sap ...	2005	16327189
changing diversity of hymenopteran parasitoids from organically and conventionally managed tea-ecosystem of north bengal, india.	tea, camellia sinensis (l.) o. kuntze, is grown conventionally (application of chemical fertilizer and pesticides) as well as organically in darjeeling hills and adjoining plains. studies on parasitic hymenoptera gain relevance due to their effective role as biocontrol agents for maintenance of ecological balance and as biological indicators of health of tea agro-ecosystem. diversity of the hymenopterans was studied using shannon-weaver index (1963) both at morphospecies and family levels. the a ...	2005	16334289
ethyl acetate extract from black tea prevents neuromuscular blockade by botulinum neurotoxin type a in vitro.	botulinum neurotoxin produced by clostridium botulinum is the strongest neurotoxin and causes botulism in mammals. the current study aimed to find an inactivator for botulinum neurotoxin in black, oolong, roasted, and green teas. the ability of the four teas to inactivate the neuromuscular blocking action of botulinum neurotoxin was determined. water extracts from black, oolong, and roasted teas protected against the toxicity of botulinum neurotoxin type a in mouse phrenic nerve-diaphragm prepar ...	2005	16638658
clinical studies to determine the effectiveness of a whitening toothpaste at reducing stain (using a forced stain model).	two single centre, randomized single-blind, crossover studies were performed, to compare the effect of a test toothpaste with a conventional fluoride paste in the inhibition and removal of extrinsic dental stain promoted by repeated chlorhexidine/tea rinses.	2005	16451374
comparison of the antioxidant activity of roasted tea with green, oolong, and black teas.	although the antioxidant properties of green, oolong, and black teas have been well studied, antioxidant activity has not been examined in roasted tea. therefore, in the current studies, we investigated the antioxidant activity of roasted tea in comparison with those of green, oolong, and black teas. using water extracts of the various teas, we examined the total phenolic content as well as the antioxidant activities, including the reducing power, the 1,1-diphenyl-2-picrylhydrazyl (dpph) radical ...	2005	16638659
inhibition of sars-cov 3c-like protease activity by theaflavin-3,3'-digallate (tf3).	sars-cov is the causative agent of severe acute respiratory syndrome (sars). the virally encoded 3c-like protease (3cl(pro)) has been presumed critical for the viral replication of sars-cov in infected host cells. in this study, we screened a natural product library consisting of 720 compounds for inhibitory activity against 3cl(pro). two compounds in the library were found to be inhibitive: tannic acid (ic(50) = 3 microm) and 3-isotheaflavin-3-gallate (tf2b) (ic(50) = 7 microm). these two compo ...	2005	15937562
tea (camellia sinensis (l.) o. kuntze) clone with lower period of winter dormancy exhibits lesser cellular damage in response to low temperature.	there is no literature available on the response of tea plant to low temperature. we studied the effect of low temperature on two clones of tea with contrasting periods of winter dormancy, a phenomenon in which the growth of apical shoots of tea is diminished during winter months. clone 'teenali 17/154' (tnl) showed shorter periods of winter dormancy than clone 'kangra jat' (knj). low temperature (5 degrees c) resulted in increase of metabolic superoxide (o2*-) content and cellular damage (as me ...	2005	15907690
water deficit induced oxidative damage in tea (camellia sinensis) plants.	when the tea (camellia sinensis) leaf water potential was -1.1 mpa (moderate water deficit), there was 58% inhibition of photosynthesis accompanied by increased zeaxanthin, malondialdehyde, oxidized proteins and superoxide dismutase activity. when the leaf water potential was -2mpa (severe water deficit), there was nearly complete inhibition of photosynthesis apart from a decrease in chlorophylls, beta-carotene, neoxanthin and lutein. water deficit at this level caused further conversion of viol ...	2005	15900883
black tea induces tumor cell apoptosis by bax translocation, loss in mitochondrial transmembrane potential, cytochrome c release and caspase activation.	recently the anti-cancer role of black tea has gained immense importance. nevertheless, the signaling pathways underlying black tea-induced tumor cell death are still unknown. previously we reported that black tea induces ehrlich's ascites carcinoma (eac) cell apoptosis by changing the balance between pro-and anti-apoptotic proteins. it is now well accepted that many cell death pathways converge at the mitochondria to decrease mitochondrial transmembrane potential (mtp) thereby releasing apoptog ...	2005	15880367
meal-based intake assessment tool: relative validity when determining dietary intake of fe and zn and selected absorption modifiers in uk men.	a computer-based dietary assessment tool, the meal-based intake assessment tool (mbiat), is described. in the current study, dietary intakes of fe and zn fractions (total fe, non-haem fe, haem fe, meat fe, total zn) and dietary components that influence fe and zn absorption (vitamin c, phytate, ca, grams of meat/fish/poultry, black tea equivalents, phytate:zn molar ratio) were assessed. the relative validity of the mbiat was determined in forty-eight uk men aged 40 years and over by comparing it ...	2005	15877881
effects of structure on radical-scavenging abilities and antioxidative activities of tea polyphenols: nmr analytical approach using 1,1-diphenyl-2-picrylhydrazyl radicals.	tea (camellia sinensis) leaves contain various antioxidants such as ascorbic acid (1) and polyphenols. this study tries to clarify the molecular mechanisms underlying the antioxidative and radical-scavenging activities of these antioxidants, and the reactivities of each antioxidant have been compared against that of the stable free radical 1,1-diphenyl-2-picrylhydrazyl (dpph, 2) using nuclear magnetic resonance (nmr) analysis. catechol (3) and (+)-taxifolin (4) were oxidized to o-quinone by 2. h ...	2005	15853407