Publications

sharing a bowl of tea.	soshitsu sen's keynote speech before a symposium on population and the environment is summarized unofficially by the editorial staff. the instability of human thinking is given as the cause for the present destruction of the environment. in a visit to the his majesty king of sweden, sen remarked that stabilizing human minds can be achieved within the tea ceremony through "serving tea heartily, receiving it with gratitude, and offering it to another." in this way, the spirit of concern for oth ...	1993	12286476
oolong tea polyphenols inhibit experimental dental caries in spf rats infected with mutans streptococci.	an extract of oolong tea (semifermented tea leaves of camellia sinensis) and its chromatographically isolated polyphenolic compound was examined for in vitro inhibitory effects on glucosyltransferases (gtases) of mutans streptococci and on caries development in sprague-dawley rats infected with mutans streptococci. the samples showed no detectable effect on the growth of mutans streptococci. however, insoluble glucan synthesis from sucrose by the gtases of streptococcus mutans mt8148r and strept ...	1993	8319255
inhibition of iron absorption prolongs the life span of drosophila.	the life span of drosophila melanogaster (oregon r) males was found to be proportional to the logarithm of the iron content of the diet. life span was also shown to be proportional to the rate of iron accumulation for drosophila, mice and man. the total body iron content was found to correlate with the total calcium content of adult drosophila. iron content during the developmental stages, however, remained relatively constant and did not change with changes in the calcium concentrations. dietar ...	1993	8326745
isolation of camelliaside c from "tea seed cake" and inhibitory effects of its derivatives on arachidonate 5-lipoxygenase.	a new flavonol glycoside, camelliaside c, was isolated from "tea seed cake" prepared from the defatted seeds of camellia sinensis o. kuntze. the structure was determined as kaempferol 3-o-beta-d-galactopyranosyl-(1-->2)-beta-d-glucopyranoside by spectroscopic methods (fab-ms, uv, ir, 1h- and 13c-nmr) and the enzymatic transformation of camelliaside c to astragalin. camelliaside c showed an inhibitory effect on the arachidonate 5-lipoxygenase of rbl-1 cells (ic50:1.4 x 10(-4)m) as did camelliasid ...	1993	8370116
inhibitory effect of tea catechins on collagenase activity.	a major purpose of this study was to examine inhibitory effect of the catechin derivatives from japanese green tea camellia sinensis on collagenase activity. the crude tea catechins, which contain (+)-catechin (c), (-)-epicatechin (ec), (+)-gallocatechin (gc), (-)-epigallocatechin (egc), (-)-epicatechin gallate (ecg), and (-)-epigallocatechin gallate (egcg), were tested for their ability to inhibit the prokaryotic and eukaryotic cell derived collagenase activities. among the tea catechins tested ...	1993	8396176
k and ca content of fresh green tea, black tea, and tea residue determined by x-ray fluorescence analysis.	x-ray fluorescence (xrf) can be successfully used for the qualitative and quantitative elemental analysis of various agricultural products. its simplicity, high throughput and the possibility of automation make it useful for screening large numbers of samples. the k and ca content of 138 samples of fresh green tea, black tea and black tea residues were determined by applying the xrf system. such a method of mineral analysis of food products is not very common. tea from different tea-growing area ...	1993	8438623
inhibitory effects of tea extracts and (-)-epigallocatechin gallate on dna synthesis and proliferation of hepatoma and erythroleukemia cells.	polyphenols extracted from green or black tea with ethyl acetate were strongly inhibitory for dna synthesis in htc rat hepatoma cells and ds19 mouse erythroleukemia cells at concentrations of 0.1-0.2 mg/ml. there was less inhibition with a subsequent black tea fraction extracted with butanol and with the residual water-soluble fraction. although cell proliferation was inhibited by (-)-epigallocatechin gallate and the tea extracts, there were only marginal effects on differentiation of ds19 cells ...	1993	8443796
enhancement of gap junctional intercellular communication in tumor promoter-treated cells by components of green tea.	green tea (camellia sinensis) has been reported to inhibit tumor promotion in vivo and in vitro. many tumor promoters inhibit gap junctional intercellular communication (gjic) which may be an important mechanism of promotion. in the present study, we hypothesized that green tea would enhance gjic in promoter-treated cells. an aqueous extract of green tea (gte) and several of its constituents were tested for their effects on gjic in p,p'-dichlorodiphenyltrichloroethane (ddt)-, 12-o-tetradecanoylp ...	1993	8481889
gastro-intestinal availability of aluminium from tea.	the in vitro speciation of aluminium (al) in black tea infusion (ph 4.8) was assessed using 3000, 10,000 and 30,000 da cut-off ultrafilters, and the effect of adding human gastric juice (ph 2.3) and then raising the ph to 6.5 were also studied. 78% al in the tea infusion passed through the 3000-da ultrafilter; this percentage increased to more than 90% with the addition of gastric juice at ph 2.3, but then reduced to approximately 5% when the incubate was adjusted to ph 6.5. the breakdown of tea ...	1993	8514217
tea and cancer.	tea is one of the most popular beverages consumed worldwide. the relationship between tea consumption and human cancer incidence is an important concern. this topic has been studied in different populations by many investigators, but no clear-cut conclusion can be drawn. whereas some studies have shown a protective effect of tea consumption against certain types of cancers, other studies have indicated an opposite effect. our purpose is to provide a critical review of this topic, covering basic ...	1993	8515490
effects of shooting period, times within shooting periods and processing systems on the extract, caffeine and crude fiber contents of black tea.	the extract, caffeine and crude fibre contents of black tea, from different shooting periods, different times within each shooting period and processed by five different commercial rolling methods, were examined. the extract and crude fibre contents of black tea were significantly (p < 0.01) affected by all these factors and their interactions. the caffeine content of black tea was affected by the shooting period and times within the shooting period. it was determined that processing methods did ...	1993	8249478
experimental studies on the treatment of frostbite in rats.	the effect of treatment by high dose of vitamin c, rapid rewarming by 37 degrees c water alone and with vitamin c, rapid rewarming by 37 degrees c decoction of indian black tea alone and with vitamin c for experimentally produced frostbite was evaluated in 6 groups (25 each) of rats. frostbite was produced experimentally in the hind limbs by exposing the animals at -15 degrees c for 1h using the harness technique. the degree of injury was assessed and classified on the basis of tissue necrosis a ...	1993	8262579
the inhibitory effect of chinese tea and its polyphenols on in vitro and in vivo n-nitrosation.	the objective of this study is to evaluate the possible role of chinese tea as a natural inhibitor of n-nitrosation, and to compare the relative inhibitory potency of various kinds of chinese tea in vitro and in vivo. studies on the inhibitory effect of 145 samples of chinese tea on the formation of n-nitrosomorpholine (nmor) showed that the inhibitory potency of the 7 types of chinese tea differed greatly, the average blocking rate of green tea (89.04%, n = 60), crush, tear, and curl (ctc) blac ...	1993	8292269
effects of seed saponins of thea sinensis l. (ryokucha saponin) on alcohol absorption and metabolism.	we evaluated the effects of the seed saponins of thea sinensis l. on alcohol absorption and metabolism in rats and mice. an ethanolic extract from the seeds of t. sinensis was orally administered to the rats 1 hr before or 0.5 hr after administration of ethanol (2 g/kg), and the blood ethanol assayed 0.5, 1, 2, 3, and 4 hr after ethanol administration. the ethanol level decreased after both pre- and post-administration of the extract. the extract was further purified to obtain a saponin fraction ...	1993	8147976
prognostic significance of selected lifestyle factors in urinary bladder cancer.	to examine the prognostic significance of lifestyle factors in urinary bladder cancer, we conducted a follow-up study of 258 incident bladder cancer patients, who were originally recruited in a case-control study in metropolitan nagoya. information on individual survivals was obtained from the computer data-file of the tumor registry of the nagoya bladder cancer research group. univariate analyses revealed significant associations of 5-year survivorship with educational attainment, marital statu ...	1993	8294212
[determination of minerals and trace elements in selenium tea from the enschi district, people's republic of china, and in its infusions using inductively coupled plasma-atomic emission spectrometry, graphite furnace atomic absorption spectrometry and instrumental neutron activation analysis].	the enschi district in hubei province, peoples republic of china is geochemically one of the two seleniferous regions, producing both selenium (se) black tea and the se green tea. three samples of green tea with different se contents and one non-se tea were analysed. the following mineral and trace elements were determined by inductively coupled plasma-atomic emission spectrometry (icp-aes): k, ca, mg, na, p, s, al, mn, fe, ba, sr, co, ni, cu, zn, mo, and cr. except for mo, co, and cr, all other ...	1993	8273425
[contents of aluminum and manganese in tea leaves and tea infusions].	we measured the contents of aluminum and manganese in tea leaves and tea infusions by means of various standardized infusion conditions, and by using flameless atomic absorption spectrophotometry, and investigated the influence of infusion conditions on the elution of aluminum and manganese into the tea infusions. furthermore, we tried to estimate the daily intake of aluminum and manganese due to drinking tea infusions. the content of aluminum in tea leaves was 1420 micrograms/g in case of wulon ...	1993	8254994
determination of flavone c-glycosides in tea.	an hplc method for the determination of flavone c-glycosides (fcg) from black tea has been developed. sample clean-up was accomplished by means of polyamide column chromatography, followed by enzyme hydrolysis of interfering compounds such was flavonol glycosides and a second polyamide column chromatographic step. using hplc with gradient elution and photodiode array detection eight fcg were separated. seven fcg were isolated by means of preparative hplc. identification was carried out using co- ...	1993	8237118
the influence of dietary factors on the risk of urinary stone formation.	the action of various beverages and foods on the composition of the urine in the circadian rhythm and in the 24-hour urine has been investigated under standardized conditions. orange juice leads to a significant increase of urinary ph and citric acid excretion. black tea leads to a raised excretion of oxalic acid by only 7.9%. in the short term, beer increases diuresis, but afterwards leads to a compensatory antidiuresis with increased risk of stone formation. depending on their composition, min ...	1993	8146611
geranyl 6-o-beta-d-xylopyranosyl-beta-d-glucopyranoside isolated as an aroma precursor from tea leaves for oolong tea.	a new geranyl glycoside, geranyl 5-o-beta-d-xylopyranosyl-beta-d-glucopyranoside was isolated as an aroma precursor from tea leaves (camellia sinensis var. sinensis cv shuixian) for oolong tea. the isolation was guided by a two-phase acid hydrolysis and/or an enzymatic hydrolysis followed by gc and gc-ms analyses.	1993	7763947
bactericidal catechins damage the lipid bilayer.	the mode of antibacterial action of, the green tea (camellia sinensis) extracts, (-)-epigallocatechin gallate (egcg) and (-)-epicatechin (ec) was investigated. strong bactericidal egcg caused leakage of 5,6-carboxyfluorescein from phosphatidylcholine liposomes (pc), but ec with very weak bactericidal activity caused little damage to the membrane. phosphatidylserine and dicetyl phosphate partially protected the membrane from egcg-mediated damage when reconstituted into the liposome membrane with ...	1993	8466924
organochlorine pesticide residues in black tea, camomile, and linden.		1993	8467130
antioxidant properties of fractions and polyphenol constituents from green, oolong and black teas.	green, oolong and black teas were extracted with water, and then the water extracts were extracted separately with three types of solvent, chloroform, ethyl acetate and butanol, to obtain eight fractions. major flavanol was extracted by etoac, while most of the alkaloid was in the chloroform fraction. thearubigin was greatest in the butanol fraction, and most of the amino acid remained in the water fraction. all fractions were systematically analyzed by uv spectrophotometer and reverse phase hpl ...	1993	7809277
a multi-institute case-control study on the risk factors of developing pancreatic cancer.	a multi-institute, hospital-based, case-control study on pancreatic cancer was carried out to examine its association with preceding diseases, cigarette smoking, alcohol drinking and dietary factors. analyses were based on 124 newly diagnosed exocrine pancreatic cancer cases and sex-, age- and institute-matched hospital controls in seven hospitals in japan. cigarette smoking showed a positive association with the risk of developing pancreatic cancer. especially among smokers, a risk enhancing ef ...	1992	1434027
tea components: antimutagenic and anticarcinogenic effects.	tea from the camellia sinensis species of the theaceae family is one of the most ancient and, next to water, the most widely consumed beverage in the world. since tea contains several polyphenols and since several other naturally occurring dietary polyphenols have shown antimutagenic effects in bacteria and anticarcinogenic effects in animal bioassay systems, we studied whether polyphenols extracted from chinese green tea (gtp) also possess antimutagenic and anticarcinogenic effects.	1992	1614996
green tea composition, consumption, and polyphenol chemistry.	tea is grown in about 30 countries but is consumed worldwide, although at greatly varying levels. it is the most widely consumed beverage aside from water with a per capita worldwide consumption of approximately 0.12 liter per year. tea is manufactured in three basic forms. green tea is prepared in such a way as to preclude the oxidation of green leaf polyphenols. during black tea production oxidation is promoted so that most of these substances are oxidized. oolong tea is a partially oxidized p ...	1992	1614995
physiological and pharmacological effects of camellia sinensis (tea): first symposium. new york city, march 4-5, 1991.		1992	1352045
micropropagation of an elite darjeeling tea clone.	shoot cultures of camellia sinensis (l.) o. kuntz var. t-78, an elite darjeeling tea clone, were established from cotyledonary nodes and shoot tips of germinated seedlings as well as from nodal explants of field grown plants. shoot multiplication rate ranged from 4x in nodal explants to 35x in cotyledonary nodes after 18 weeks of culture. rooting was achieved in 80-90% micro-shoots by either placing them on an inductive medium for 10 d and then transferring shoots to hormone-free medium, or by t ...	1992	24213495
preparation of congou black tea from stale green tea.		1992	27280839
site-specific dna cleavage by mammalian dna topoisomerase ii induced by novel flavone and catechin derivatives.	four naturally occurring flavones (baicalein, quercetin, quercetagetin and myricetin) and two novel catechins [(-)-epicatechin gallate and (-)-epigallocatechin gallate, from the tea plant camellia sinensis], which are known inhibitors of reverse transcriptase, were shown to induce mammalian topoisomerase ii-dependent dna-cleavage in vitro. the flavones differed from the catechins in causing unwinding of duplex dna, but both classes of compound induced enzymic dna breakage at the same sites on dn ...	1992	1313232
[protective activity of tea and catechins against bordetella pertussis].	we examined the bactericidal activity of tea and catechins against bordetella pertussis. green tea, black tea and coffee showed marked bactericidal activity at their concentrations in beverages, while pu-erh tea killed the bacteria in a moderate way. (-) epigallocatechin gallate (egcg) and theaflavin digallate (tf3) showed also marked bactericidal activity. green tea and black tea also effectively blocked the adhesion of b. pertussis to hela and cho cells, whereas ecgg and tf3 could not. egcg an ...	1992	1402092
[antimicrobial and microbicidal activities of tea and catechins against mycoplasma].	we examined tea extracts, (-) epigallocatechin gallate (egcg) and theaflavin digallate (tf3) for their antimicrobial and microbicidal activities against mycoplasma. green tea and black tea showed antimicrobial activities against m. pneumoniae. at a concentration of 0.2% green tea and black tea showed microbicidal activities against m. pneumoniae and m. orale but not against m. salivarium. extracts of pu-erh tea showed a slight microbicidal activity against m. pneumoniae and m. orale. egcg purifi ...	1992	1402093
(-)-epigallocatechin-3-gallate in camellia sinensis leaves from himalayan region of sikkim: inhibitory effects against biochemical events and tumor initiation in sencar mouse skin.	recently, we and others showed that the components of green tea may be useful cancer chemopreventive agents. it has been suggested that (-)-epigallocatechin-3-gallate (egcg), the major constituent in green tea, may possess antitumor-promoting and/or anticarcinogenic effects in rodent tumor bioassay systems. during the chemical analysis of various green tea products, we found a traditionally preserved preparation of green tea used by tribes in the himalayan region of sikkim, india that was rich i ...	1992	1408948
antioxidative effect of polyphenol extract prepared from various chinese teas.	methods. twelve different types of chinese teas, including green, semifermented, and black tea, were studied for their antioxidant activities and active components. compositions of (-)-epicatechin, (-)-epigallocatechin, (-)-epicatechin gallate, (-)-epigallocatechin gallate, and gallic acid were identified by fast atom bombardment-mass spectrometry and high-performance liquid chromatography-mass spectrometry and quantified by high-performance liquid chromatography. antioxidant activities in lard ...	1992	1409493
[microbial contamination of twenty drugs of plant origin].	twenty drugs of plant origin were analysed in order to determine the microbial contamination level. a light homogenizing method was used to avoid an increase in the antimicrobial capacity of certain drugs, which would falsify the analytical results. the total viable aerobic count (tvc) varied from 10(1) to 10(7) cfu/g and in 11 samples out of 21 was equal to or higher than 10(5) cfu/g. the number of fungi varied from one drug to another, but was generally lower than the aerobic tvc to the power ...	1992	1438458
inhibition of n-nitrosodiethylamine- and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone-induced tumorigenesis in a/j mice by green tea and black tea.	the effect of p.o. administration of tea on nitrosamine-induced carcinogenesis was investigated. female a/j mice were given n-nitrosodiethylamine (ndea) (10 mg/kg) p.o. once a week for 8 weeks and were killed 16 weeks after the last dose. more than 90% of the mice had forestomach and lung tumors. the animals had an average of 8.3 forestomach and 2.5 lung tumors/mouse. with 0.63 or 1.25% green tea infusion (12.5 g green tea leaves brewed with 1 liter of boiling water) as the sole source of drinki ...	1992	1551122
the effects of chinese tea on the occurrence of esophageal tumors induced by n-nitrosomethylbenzylamine in rats.	based on previous studies on the blocking effect of chinese tea in the formation of n-nitroso compounds in rats and humans, experiments were carried out to study the effects of chinese tea on the occurrence of esophageal tumors induced by n-nitrosomethylbenzylamine (nmbza) in rats.	1992	1615000
cytotoxicity of coffee in human intestinal cells in vitro and its inhibition by peroxidase.	the cytotoxic effects of dried preparations of nine different beverages, including alcoholic drinks, on human embryonic intestinal cells in vitro and the cytoprotective effects of several enzymes were examined. instant coffee and green tea were the most cytotoxic beverages (id(50) value 0.016 ml equivalents/ml). peroxidase (0.015 units/ml) completely nullified the cytotoxic effects of instant coffee, green tea and black tea; catalase had a less protective effect. in contrast, superoxide dismutas ...	1992	20732140
anticaries effects of polyphenolic compounds from japanese green tea.	the dental caries inhibiting effect of the extract from japanese green tea, one of the most popular drinks in japan, was studied both in vitro and in vivo. the crude tea polyphenolic compounds (designated sunphenon) from the leaf of camellia sinensis were found to effectively inhibit the attachment of streptococcus mutans strain jc-2 (serotype c) to saliva-coated hydroxyapatide discs. sunphenon was also inhibitory to water-insoluble glucan formation from sucrose by crude glucosyltransferase of s ...	1991	1667297
the inhibitory effect of plant extracts on the collagenolytic activity and cytotoxicity of human gingival fibroblasts by porphyromonas gingivalis crude enzyme.	it is well known that plant extracts inhibit some enzymatic activities. the present study examined the inhibitory effects of natural plant extracts against the collagenolytic activity of porphyromonas gingivalis. the enzyme was isolated from a culture supernatant of p. gingivalis 381. the aqueous and 50% ethanolic extracts of ginkgo biloba, mosla chinensis, salvia officinalis, cinnamomum cassia, and a catechin extract of camellia sinensis exhibited strong inhibitory effects on collagenolytic act ...	1991	1668071
inhibition of rotavirus and enterovirus infections by tea extracts.	epigallocatechin gallate from green tea and theaflavin digallate from black tea inhibited infections of cultured rhesus monkey kidney ma 104 cells with rotaviruses and enteroviruses. their antiviral effects were maximally induced when directly added to virus, and their pre- and post-treatment of the cells produced much weak antiviral activity. antiviral activity of the extracts therefore seems to be attributable to interference with virus adsorption.	1991	1668240
dietary nicotine: a source of urinary cotinine.	foods, principally from plants in the family solanaceae, and a number of teas were examined for the presence of nicotine. dietary nicotine would give rise to cotinine in urine and compromise estimates of exposure to tobacco smoke that depend on urinary cotinine. all foods were homogenized, extracted and analysed for nicotine and cotinine by gas chromatography with nitrogen-sensitive detection (gc) and/or gc/ms (mass spectrometry). weak acid and aqueous extracts of the teas were analysed in a sim ...	1991	1765327
niacin, thiamin, iron and protein status of humans as affected by the consumption of tea (camellia sinensis) infusions.	the objective of the project was to determine the effects of tea (camellia sinensis) leaf beverage consumption on the apparent utilization of niacin, thiamin, and protein in human subjects. during two randomly arranged experimental periods of 14 days each, 10 adult female human subjects were fed a constant (same foods each day), measured, laboratory-controlled diet. tea was fed during one period while no tea was allowed during the other period. a dehydrated black tea infusion product (instant te ...	1991	1796091
tea tannin components modify the induction of sister-chromatid exchanges and chromosome aberrations in mutagen-treated cultured mammalian cells and mice.	the modifying effects of tannin components extracted from green tea and black tea on mutagen-induced sces and chromosome aberrations were studied. these tannin components did not affect spontaneous sces and chromosome aberrations in cultured chinese hamster cells. the frequency of sces and chromosome aberrations induced by mitomycin c (mmc) or uv was enhanced by the posttreatment with tea tannin components. when cells were post-treated with tea tannin components in the presence of metabolic enzy ...	1991	1899132
mutagenicity and carcinogenicity of tea, camellia sinensis.	aqueous, caffeine free and tannin fractions of commercial tea and tannic acid were tested for mutagenicity in ames test. tea fractions of tannic acid were non mutagenic in strains ta 100, ta 98, ta 1535 and ta 1538 of salmonella typhimurium with or without metabolic activation (rat-s9 mix) at different doses tested. in strain ta 98 the above tea fractions and tannic acid inhibited the s9 mix mediated mutagenicity of tobacco in a dose dependent manner. the different tea fractions at 60 degrees c, ...	1991	1916936
inhibition of platelet activation and endothelial cell injury by flavan-3-ol and saikosaponin compounds.	the effects of flavan-3-ol and saikosaponin compounds on platelet aggregation, platelet thromboxane biosynthesis and h2o2-induced endothelial cell injury were studied. seven flavan-3-ol compounds isolated from camellia sinensis l. var sinensis o. kuntze (theaceae) and three saikosaponin compounds isolated from bupleurum falcatum l. (umbelliferae) were used. among the 10 compounds tested, only epigallocatechin and saikosaponin a significantly inhibited human platelet aggregation induced by adp, a ...	1991	1946562
the protective activity of tea against infection by vibrio cholerae o1.	extracts of black tea exhibited bactericidal activity against vibrio cholerae o1. the tea extract inhibited the haemolysin activity of v. cholerae o1, el tor and the morphological changes of chinese hamster ovary cells induced by cholera toxin. tea extract also reduced fluid accumulation induced by cholera toxin in sealed adult mice and by v. cholerae o1 in ligated intestinal loops of rabbits. these findings suggest that tea has protective activity against v. cholerae o1.	1991	2019547
[quantitative analysis of (-)-epigallocatechin gallate in tea leaves by high-performance liquid chromatography].	the quantitative analysis of (-)-epigallocatechin gallate (egcg) in tea (camellia sinensis l.) was performed by high-performance liquid chromatography (hplc) with a c-18 reversed-phase column. egcg was then eluted within 20 min by using methanol-water-acetic acid (20:75:5 (v/v/v)) as an eluent. as an internal standard, tryptophan was used. the content of egcg in five kinds of green tea (sencha, gyokuro, bancha, matsucha and oolong tea) and in a cup of those was determined by both the extraction ...	1991	1806661
inhibitory effect of chinese tea on n-nitrosation in vitro and in vivo.	the inhibitory effect of 145 samples of chinese tea on the formation of n-nitrosomorpholine was studied in vitro. the rates of inhibition by green tea, crush, tear, curl (ctc) black tea, brick tea, jasmine tea, oolong tea, sun-dried tea and black tea were positively correlated with their polyphenol contents. an inhibitory effect of green and black tea on endogenous n-nitrosation was also confirmed in humans. drinking tea after a meal had a greater effect than drinking it before a meal.	1991	1855915
two flavonol glycosides from seeds of camellia sinensis.	two novel flavonol triglycosides, camelliaside a and b, have been isolated from seeds of camellia sinensis. the structures were determined to be kaempferol 3-o-[2-o-beta-d- galactopyranosyl-6-o-alpha-l-rhamnopyranosyl]-beta-d-glucopyranoside and kaempferol 3-o-[2-o-beta- d-xylopyranosyl-6-o-alpha-l-rhamnopyranosyl]-beta-d-glucopyranoside on the basis of spectroscopic, chemical and enzymatic studies. these types of interglycosidic linkages, gal(1----2)[rha(1----6)]glc and xyl(1----2)[rha(1----6)] ...	1991	1368184
flavonol triglycosides containing galactose in tea.	the isolation and structural elucidation of new quercetin and kaempferol triglycosides from camellia sinensis is described. their structures were determined as quercetin and kaempferol 3-glucosyl(1----3) rhamnosyl(1----6)galactosides. the content of quercetin glucosylrhamnosylgalactoside ranged between 0 and 87 mg per 100 g, and that of the kaempferol homologue between 0 and 119 mg per 100 g dry wt.	1991	1367342
[fluoride content of deciduous teeth after regular intake of black tea].	continuous intake of black tea rich in fluorides leads to distinct increase of fluoride content of temporary teeth. this is to consider analogous a caries prophylaxis.	1990	2268641
production of theanine and other γ-glutamyl derivatives by camellia sinensis cultured cells.	the maximum theanine production by camellia sinensis cultured cells was achieved by culturing in the modified ms medium containing 2 mg/l indole-3-butyric acid, 0.1 mg/l kinetin, 0 mm nh4no3 and 39.6 mm kno3 with 40 mm ethylamine hydrochloride or 20 mm ethylamine hydrochloride and 10 mm l-glutamic acid. other primary amines, such as methylamine, n-butylamine, 2-hydroxyethylamine, 2cyanoethylamine, aniline, benzylamine and phenylethylamine, were also biotransformed to n(5)-alkyl-l-glutamine deriv ...	1990	24226431
counter-current chromatography of black tea infusions.	counter-current chromatography using a multilayer coil planet centrifuge, with solvent system ethyl acetate-butanol-water, permits the separation of black tea infusions into fractions which include pure sii and a mixture of si and sia thearubigins. good resolution of several components of the infusion may be achieved in elution times of 1 to 2 h. the appearance of chromatograms is altered on decaffeinating the infusion. the effect of stationary phase composition is considered. resolution of the ...	1990	2355066
[a case control study of cancer of the pancreas].	we report the findings of a case-control study of cancer of the pancreas, which was conducted in hokkaido prefecture. seventy-one patients with pancreatic cancer were matched on sex and age (+/- 3 years) to 142 community-based controls. the latter had telephone interviews. we questioned all subjects about demographic factors, diet, beverage consumption, and medical and surgical history. significantly decreased risks were associated with consumption of raw vegetables and green tea. the risk incre ...	1990	2313889
[the effect of a black tea extract on the tumor-like growth of the fungus fusarium bulbigenum var. blasticola].	the antiblastogenic activity of black tea is predicted with a 98% credibility basing on the observation of its inhibitory or preventive effect on spontaneous or carcinogen-induced tumor development in the culture of mycelial fungus fusarium bulbigenum var. blasticola.	1990	2316201
[anti-caries effects of polyphenol compound from camellia sinensis].	polyphenol compound (designated sunphenon) from leaf of camellia sinensis have been partially purified by extraction of the boiling water with ethyl acetate. the effect of sunphenon on cariogenic streptococcus mutans groups (serotype c and g) was studied in both in vitro and in vivo. the summary of results were described as follows; 1) addition of sunphenon to s. mutans jc-2 (c) caused a decrease in cell viability. the activity of sunphenon showed that multiple application are required for killi ...	1990	2135607
effect of tea polyphenols on glucan synthesis by glucosyltransferase from streptococcus mutans.	in the course of our studies on the development of anti-plaque agents for prevention of dental caries, we investigated effects of some of tea preparations and their individual components on the glucan synthesis catalyzed by glucosyltransferase (gtf) from streptococcus mutans. extracts of green tea and black tea, and polyphenol mixtures showed appreciable inhibition in the synthesis of insoluble glucan. among the components isolated from tea infusions, theaflavin and its mono- and digallates had ...	1990	2140716
differential inhibitory effects of some catechin derivatives on the activities of human immunodeficiency virus reverse transcriptase and cellular deoxyribonucleic and ribonucleic acid polymerases.	the two components of camellia sinensis (tea plant) [i.e., (-)-epicatechin gallate and (-)-epigallocatechin gallate] were found to differentially inhibit the activities of reverse transcriptase and cellular dna and rna polymerases. under the assay conditions optimized for each enzyme species, the strongest inhibition by these compounds was observed with reverse transcriptase. the concentrations of (-)-epicatechin gallate and (-)-epigallocatechin gallate required for 50% inhibition of the activit ...	1990	1693287
differential inhibition of hiv-reverse transcriptase and various dna and rna polymerases by some catechin derivatives.	the two components of camellia sinensis (green tea) (i.e., (-)-epigallocatechin gallate and (-)-epicatechin gallate were found to differentially inhibit the activities of reverse transcriptase and cellular dna and rna polymerases. the strongest inhibition by these compounds was observed with reverse transcriptase. dna polymerases alpha and beta were also strongly inhibited. the mode of the inhibition of reverse transcriptase and other dna polymerases was competitive with respect to the template. ...	1989	2481838
crude tea extracts decrease the mutagenic activity of n-methyl-n'-nitro-n-nitrosoguanidine in vitro and in intragastric tract of rats.	the effects of tea extracts and their ingredients, catechins and l-ascorbic acid (asa), on the mutagenicity of n-methyl-n'-nitro-n-nitrosoguanidine (mnng) were examined in vitro and in the stomachs of rats using e. coli wp2 and s. typhimurium ta100. the extracts of green tea and black tea leaves decreased the mutagenic activity of mnng to e. coli wp2 in vitro in a desmutagenic manner. catechins such as (-)-epigallocatechin from green tea leaves and the low-molecular-weight tannin fraction isolat ...	1989	2642597
effect of consumption of green and black tea on the level of various enzymes in rats.	drinking of both green and black tea as the only liquid ingested resulted in significant decreases in the activity of transketolase in whole blood of rats both before and after the in vitro addition of thiamin diphosphate. liver transketolase activity was decreased only by green tea. mucosal transketolase activity was not affected by either type of tea. the activity of lactate dehydrogenase (ldh) was not affected by either type of tea, while whole blood ldh was decreased by both green and black ...	1989	2912766
chromosome aberrations induced by aflatoxin b1 in rat bone marrow cells in vivo and their suppression by green tea.	aflatoxin b1 (afb1)-induced chromosome aberrations (ca) in rat bone marrow cells consisted mainly of gaps and breaks. cells with exchanges and multiple ca were observed infrequently. the incidence of aberrant cells and the number of aberrations per cell were at their maximum levels 18 h after the afb1 injection. they were dependent on the administered dose of afb1. rats given the hot water extract from green tea (gte) 24 h before they were injected with afb1 displayed considerably suppressed afb ...	1989	2922009
characteristics of past smokers.	we studied characteristics of past smokers according to the duration of cessation of smoking based on data from a population-based survey. lifestyle, prevalences of various symptoms and diseases and other factors were compared among current smokers (8507 males and 2012 females), past smokers (4423 males and 684 females) and non-smokers (2431 males and 12,859 females) aged 40 years and over. compared to current smokers, past smokers consumed more bread, milk, vegetables, fruit and black tea, and ...	1989	2788628
factors related to late menopause and early menarche as risk factors for breast cancer.	to investigate underlying factors of late menopause and early menarche which are regarded as risk factors for breast cancer, we analyzed the relationships between ages at menarche and menopause, and other environmental and physical factors using the data of a population-based survey conducted in aichi prefecture, japan. the analysis on menopause was based on 3,148 women aged 55 or more and the analysis on menarche was based on 16,392 women aged 40 or more. these subjects were grouped into three ...	1988	3130350
folklore therapeutic indigenous plants in periodontal disorders in india (review, experimental and clinical approach).	though a number of plants and their parts are used for dental ailments among population in rural and urban areas of developing countries, in india however, the most common house-hold, road-side plants are mango (mangifera indica), neem (azadirachta indica; melia azadirachta), ocimum (ocimum basilicum), tea-dust (camellia sinensis) and uncommonly murayya, i.e., currey leaf (murayya koenigi) [chopra et al. 1958, kirtikar and basu 1935, nadakarni 1954, satyavati 1984]. the leaves of these plants ar ...	1988	3042642
iron, copper and zinc metabolism of rats fed various levels and types of tea.	the effects of tea and components in tea on mineral metabolism were investigated in a series of studies. in studies a and b weanling rats were fed diets containing various levels (0, 0.35, 1.17 or 3.50%) of a commercially prepared instant tea and diets containing 0 or 1.17% catechin. in study c anemic rats were fed diets containing 0 or 2.31% desiccated green or black tea infusions for 23 d. in study d rats were fed a diet containing 2.31% desiccated black tea infusions for 16 d, were fed the te ...	1988	3335939
[effect of six edible plants on the development of afb1-induced gamma-glutamyltranspeptidase-positive hepatocyte foci in rats].	six edible plants, green tea (gt), black tea (bt), lentinus edodes (berk) sing (le), hericium erinaceus (bull. ex fr.) pers. (he), mixture of ganoderma lucidum (ley ss ex fr.) karst et ganoderma japanium (fr.) lloyd (mglj) and mung bean (mb), were tested for the effect on the development of afb1-induced gamma-glutamyltranspeptidase positive hepatocyte foci (gamma-gt foci) using an in vivo short-term test model in rats. the rats received intraperitoneally 12 doses of initiator afb1, 400 microgram ...	1987	2443327
[the structures of two new flavonoid glycosides from bai-shui-cha, a kind of camellia sinensis l].		1987	3661207
black tea consumption and cancer risk: a prospective study.	in a prospective cohort study, men of japanese ancestry were clinically examined from 1965 to 1968. for 7,833 of these men, data on black tea consumption habits were recorded. since 1965, newly diagnosed cancer incidence cases have been identified: 152 colon, 151 lung, 149 prostate, 136 stomach, 76 rectum, 57 bladder, 30 pancreas, 25 liver, 12 kidney and 163 at other (miscellaneous) sites. compared to almost-never drinkers, men habitually drinking black tea more than once/day had an increased re ...	1986	3778808
pesticide residues in black tea.	an investigation of residues of organochlorine and organophosphorous pesticides, as well as of a number of fungicides and of inorganic bromide in 99 samples of black tea taken on the danish market is reported. the type of pesticide residues involved appear to be very uniform within each country of origin, whereas there are distinct differences between individual countries. tea from sri lanka seems to contain less and fewer residues than tea from the other big tea producing countries. a great man ...	1986	3751325
protein conversion efficiencies of four test diets based on milk, two milk and tea treatments, and casein.	milk consumption in 80 households in western kenya averaged .25 to 1.00 l per family per day. most of this milk was processed into a milk and tea beverage. polyphenols, the major determinants of tea flavor and character, form soluble complexes with casein when black tea infusions are mixed with milk. test diets were prepared from the following treatments: a) casein reference diet; b) milk, no tea leaves; c) milk added after heat treatment; and d) traditional kenyan-style tea (i.e., milk and tea ...	1986	3722539
mutagens in coffee and other beverages.	a cup of coffee contains mutagens which produce about 5 x 10(4)-10(5) revertants of salmonella typhimurium ta 100 without s9 mix. one of the mutagens was identified to be methylglyoxal. methylglyoxal was present in various beverages such as black tea, whisky, and brandy. methylglyoxal itself induced tumors in rats when administered by subcutaneous injection. however, the mutagenic properties of coffee were different from those of methylglyoxal. the mutagenicity of coffee was suppressed by catala ...	1986	3757962
detection and chemical identification of natural bio-antimutagens. a case of the green tea factor.	a bio-antimutagen, isolated from japanese green tea (leaves of camellia sinensis), reduced high spontaneous mutations due to altered dna-polymerase iii in a mutator strain of bacillus subtilis. chemical studies showed that the factor was epigallo-catechin-gallate (egcg).	1985	3923334
case-control study of urinary bladder cancer in metropolitan nagoya.	we conducted a population-based case-control study of patients with bladder cancer and of controls drawn randomly from the general population of metropolitan nagoya and interviewed both groups. the incidence rates of bladder cancer were 2.42 and 7.05/100,000 for females and males, respectively. the analysis, based on 293 patients and 589 controls who were frequency matched for age, sex, and residence, provided the following major findings. age-adjusted relative risks of 1.89 (1.15-3.10) and 3.53 ...	1985	3834338
[renal fluoride secretion following the drinking of black tea].		1984	6730563
[fluorides--black tea--health].		1984	6523919
natural antioxidants. i. antioxidative components of tea leaf (thea sinensis l.).		1984	6467480
diphenylamine, an antihyperglycemic agent from onion and tea.	diphenylamine has been isolated as one of the active antihyperglycemic agents of onion. it was identified by ir, uv, cmr, pmr, and mass spectra. it attained the highest percentage in mature onion bulbs; other onion organs contained diphenylamine in lower percentages. green and black teas were found to contain relatively high percentages of diphenylamine, being higher in the former. cooking was found to decrease the diphenylamine content.	1984	6512531
the influence of dietary tea, coffee and cocoa on protein and energy utilization of soya-bean meal and barley in rats.	two series of balance experiments were performed with growing rats to test the effect of black tea, green tea, coffee and cocoa on protein and energy utilization. in expt 1 soya-bean meal was fed as a basal diet and supplemented with freeze-dried materials from 11 black tea, green tea or coffee/500 g dry matter. cocoa powder, corresponding to 11 of the beverage, was also added to the basal diet. in expt 2 the procedure was repeated with a barley-based diet. in both experiments both tea varieties ...	1983	6684477
folacin content of tea.	total folacin and free folacin activities of 22 commercial tea samples, involving 5 types and 14 brands, were determined by a microbiological assay, using lactobacillus casei (atcc 7469). substantially higher amounts of folacin were found in tea leaves than had been reported previously, due to an improved assay method with added ascorbic acid to protect the labile folate forms. tea brews made from green and black teas contained approximately three to four times more folacin than the brews made f ...	1983	6853937
mutagenicity of various japanese foodstuffs treated with nitrite.	mutagenic activities of various japanese foodstuffs treated with nitrite at ph 4.2 for 10 min (37 degrees c) were tested using salmonella typhimurium ta 100, ta 1535 and also a streptomycin(sm)-dependent strain of salmonella typhimurium ta 100. among 46 common food samples tested, smoked ham, red wines, black teas, soybean pastes and instant coffee powder gave greatly increased numbers of his+ revertants or sm-independent colonies when treated with nitrite. vegetables, soybean-seasonings and a v ...	1982	7141563
prophylactic effect of tea on pathogenic microorganism infections to humans and animals. (ii). protozoacidal effect on toxoplasma gondii in vitro and mice.	the trophozoites of toxoplasma gondii strain (rh) obtained from the peritoneal exudate of infected mice were treated with tea in various concentrations of 0.5, 1, 3 and 5% for 0.5, 1 and 3 hours, respectively. after treatment, they were intraperitoneally inoculated into the mice to observe the protozoacidal effect of tea. the results obtained are as follows: 1) oolong tea and green tea had stronger protozoacidal effect than black tea. 2) the lowest and effective concentration of tea tested to ki ...	1982	7169306
[effect of triterpene glycosides and polyene antibiotics on cell membrane permeability for k+ ions and uv-absorbing substances].	the effect of triterpene glycosides (cauloside c from caulophyllum robustum, theasaponine from thea sinensis, cucumarioside g from cucumaria fraudatrix stichoposide a from stichopus japonicus s., holothurines a and b from holothuria mexicana, holothurine c from bohadschia sp.) on the membrane permeability for k+ ions and uv-absorbing substances was compared with that of polyene antibiotics, viz., amphotericine b and nystatine. as a biological model fertilized eggs of sea urchin strongylocentrotu ...	1981	7198783
mutagenicity of hydrolysates of tea infusions.	hydrolysates of infusions of green tea and black tea were mutagenic by the ames test. the tea infusions were prepared by a regular method and were hydrolysed with 1 m hcl, hesperidinase, naringinase and human intestinal bacteria. the hydrolysates were successively extracted with chloroform, diethyl ether and ethyl acetate. the mutagenicities of the extracts were assayed by the ames test, and the mutagens were analysed by gc-ms. the ether extracts of the hydrolysates of infusions of both green te ...	1981	7019686
inhibition of passive cutaneous anaphylaxis by compounds of camellia sinensis.		1981	7255570
prophylactic effect of tea on pathogenic micro-organism infection to human and animals. (1). growth inhibitive and bacteriocidal effect of tea on food poisoning and other pathogenic enterobacterium in vitro.	0.5% tea powder of oolong tea, green tea and black tea, respectively added to tryptic soy agar (tsa) plates prepared non aseptically could inhibit the growth of colonies of st. aureus and airborne bacteria, but only very few fungi colonies. 0.5% tea powder of oolong tea, green tea and black tea, respectively added to tryptic soy agar (tsa) plates prepared non aseptically could also inhibit the colonial growth of v. cholerae, v. parahaemorrhagiae, sal. dysenteriae, sal. typhi, sal. paratyphi a an ...	1980	7251263
effect of feeding coffee and its lipids on regenerating and intact liver.	liver regeneration was stimulated in partially hepatectomized rats fed diets supplemental with up to 7.0% by weight of ground green and roasted brazilian or hawaiian (kona) coffee in a basal powdered ration but was little influenced by decaffeinated or african robusta coffee diets over a period of 10 days. the causative agent occurred in the total lipids from the active ground coffee batches and could be concentrated in the unsaponifiable portion as was also noted with the product from robusta c ...	1980	7403660
mutagens in coffee and tea.	coffee prepared in the usual way for drinking contains a substance(s) that is mutagenic to salmonella typhimurium ta100 without mammalian microsomal enzymes. one cup of coffee (200 ml) contains mutagen(s) inducing 1.4-4.6 x 10(5) revertants under standard conditions. instant coffee too is mutagenic to ta100 and one cup of instant coffee prepared from 1 g of coffee powder and 200 ml of water induced 5.6-5.8 x 10(4) revertants of ta100. caffeine-free instant coffee also has similar mutagenicity. a ...	1979	390384
[fluorine content in the urine and in the serum of hydrofluoric acid workers as an index of health administration (author's transl)].	the behavior of fluoride ion level in the urine and in the serum was measured as an index for health care of workers exposed to hydrofluoric acid, the effect of fluorine-containing foodstuff intake by the workers being considered at the same time. for this study, 250 hydrofluoric acid workers and as a control group 1,600 non-hydrofluoric-acid workers were examined. all workers, ranging in age from 15 to 59 years old, came from the same electronics factory. fluorides in the biological fluids were ...	1979	537219
[effect of triterpene glycosides on plasma membrane permeability for uv-absorbing substances in saccharomyces carlsbergensis yeast cells].	the effect of triterpene glycosides of cauloside c from caulophyllum robustum m, stichoposide a from stichopus japonicus s. and theasaponine from thea sinensis z. on permeability of plasmic membranes of saccharomyces carlsbergensis for uv-absorbing substances was studied. it was found that incorporation of 14c-uridine from the endocellular pool into the yeast acid-insoluble fraction decreased under the effect of the triterpene glycosides as a result of the precursor leakage from the cell into th ...	1979	34359
[the effect of rooibos tea on iron absorption].	a study was carried out to determine if rooibos tea (aspalathus linearis) has a deleterious effect on iron absorption similar to that of ordinary tea (camellia sinensis). three groups of volunteers, each consisting of 10 healthy young men comparable with regard to iron status and body dimensions, were studied. after ingestion of 1 muci 59fe and 16 mg of elemental iron, group a drank rooibos tea, group b ordinary tea and group c boiled water. iron absorption was measured 14 days later with a whol ...	1979	462276
caffeine content of common beverages.	tea, coffee, carbonated and chocolate beverages were analyzed for caffeine, and results compared in terms of usual serving sizes. significant differences in caffeine levels were found to result from the preparation method of coffee or brewing time of tea. it is possible for a cup of tea, instant coffee, or can of cola beverage to have similar caffeine content (55 to 65 mg.); however, the mean values per cup of black tea (28 to 46 mg.) are considerably lower than for brewed coffee (107 to 151 mg. ...	1979	762339
[nickel, cobalt, iron, manganese, zinc and chromium content of black tea and the distribution of these metals between prepared infusion and the extracted tea leaves (author's transl)].	twentytwo samples of black tea were examined for nickel, cobalt, iron, manganese and chromium by atomic absorption spectro-photometry. the amounts of these metals in the tea beverage as well as the amount remaining in the tea leaf residue was determined in duplicate experiments. from these results the proportion of each metal extracted may be calculated, as well as its concentration in the tea beverage prepared under defined conditions.	1978	695959
[effect of triterpene glycosides on the plasma membrane permeability for amino acids in saccharomyces carlsbergensis yeast cells].	the effect of triterpen glycosides, such as cauloside c from caulophyllum robustum, stichoposide a from stichopus japonicus s and the asaponine from thea sinensis l on permeability of the plasmic membranes for amino acids was studied. it was shown that the glycosides induced higher levels of liberation of the amino acids with positively or negatively charged molecules from the cells of saccharomyces carlsbergensis as compared to the control. the transport of the non-polar amino acids was least a ...	1978	623450
[effect of triterpene glycosides on the biosynthesis of sterols and fatty acids by the yeast saccharomyces carlsbergensis].	the effect of cauloside c from caulophyllum robustum m., theasaponine from thea sinensis l. and stichoposide a from stichopus japonicus s. on the biosynthesis of sterols and fatty acids by the yeast saccharomyces carlsbergensis was studied. in in vivo and in vitro experiments cauloside c and theasaponine inhibited ergosterol biosynthesis at the stage of squalene-to-lanosterol transformation. in in vivo experiments stichoposide a inhibited squalene biosynthesis. the triterpene glycosides tested s ...	1978	724665
[effect of triterpene glycosides on rna biosynthesis in a yeast cell culture of saccharomyces carlsbergensis].	the effect of triterpen glycosides of cauloside c from caulophyllum robustum, theasaponine from thea sinensis ahd stichoposide a from stichopus japonicus on multiplication and biosynthesis of rna in the cells of a 7-hour culture of saccharomyces carlsbergensis was studied. it was shown that cauloside c, theasaponine and stichoposide a in concentrations of 7.5 gamma/ml inhibited multiplication of the yeast cells by 65, 10 and 90 per cent respectively. the summation rna of the yeast cells is divid ...	1977	911157
carcinogenicity of camellia sinensis (tea) and some tannin-containing folk medicinal herbs administered subcutaneously in rats.	in an attempt to correlate the high incidence of esophageal carcinoma in natives of certain places with their habit of using herbaceous folk medicines, we performed bioassays of several plant extracts and the fractions prepared from them. fourteen extracts and fractions from 6 plants were injected sc into nih black rats. the tannin fractions from quercus falcata pagodaefolia, diospyros virginiana, and camellia sinensis were very active and produced tumors at the injection site in 66% or more of ...	1976	187761
metabolism of methionine and biosynthesis of caffeine in the tea plant (camellia sinensis l.).	1. caffeine biosynthesis was studied by following the incorporation of 14c into the products of l-[me-14c]methionine metabolism in tea shoot tips. 2. after administration of a 'pulse' of l-[me-14c]methionine, almost all of the l-[me-14c]methionine supplied disappeared within 1 h, and 14c-labelled caffeine synthesis increased throughout the experimental periods, whereas the radioactivities of an unknown compound and theobromine were highest at 3 h after the uptake of l-[me-14c]methionine, followe ...	1976	1008848
further investigation of the biosynthesis of caffeine in tea plants (camellia sinensis l.). methylation of transfer ribonucleic acid by tea leaf extracts.	1. the trna methyltransferase activity in vitro of leaves, cotyledons and roots of 85-day-old tea seedlings was studied. 2. the activity of extracts prepared from tea leaves with polycar at (insoluble polyvinylpyrrolidine) had optimum ph7.7 and was greatly influenced by thiol compounds, but only slightly by metal ions and ammonium acetate. 3. the activities of extracts, expressed per mg of protein, were as follows: roots greater than leaves greater than cotyledons. the only methylated base isola ...	1976	12749