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influence of different fermentation raw materials on pyrolyzates of pu-erh tea theabrownin by curie-point pyrolysis-gas chromatography-mass spectroscopy.in this study, pu-erh tea was prepared by solid-state fermentation of the sun-dried green tea, short-fermentation black tea, and black tea. ultraviolet-visible spectroscopy, infrared spectroscopy and curie-point pyrolysis-gas chromatography-mass spectroscopy (cp-py-gc/ms) were used to study the characteristics and chemical compositions of the tb formed in these pu-erh teas.201323270831
travelling with tea: a tuckerella's tale.tuckerella japonica ehara appears strongly associated with tea (camellia sinensis (l.) kuntze, theaceae) and, due to certain cultural practices in tea production, has in fact become a world traveller, accompanying the greatly coveted tea plant as it spread across the planet. the history of tea production and culture, and its arrival in the usa, provides the backdrop for this traveller's tale. tuckerella japonica is morphologically similar to t. flabellifera miller, described from tasmania in aus ...201323266716
compositional analysis of leaf cuticular membranes isolated from tea plants (camellia sinensis l.).chemical constituents of cuticular membranes (cms) isolated from three tea cultivars (camellia sinensis (l.) o. kuntze cvs. yabukita, samidori and gokou) were compared. all cms from the adaxial side of the leaves showed higher accumulation of wax, cutin and polysaccharide, while those from the abaxial side were abundant in cutan, showing the adaptation of the adaxial side to abiotic stresses, such as wind and rain, in contrast to the abaxial side, which provides defence against pathogens. yabuki ...201323265489
the effect of green tea extract on fat oxidation at rest and during exercise: evidence of efficacy and proposed mechanisms.green tea is made from the leaves of the camellia sinensis l plant, which is rich in polyphenol catechins and caffeine. there is increasing interest in the potential role of green tea extract (gte) in fat metabolism and its influence on health and exercise performance. a number of studies have observed positive effects of gte on fat metabolism at rest and during exercise, following both shorter and longer term intake. however, overall, the literature is inconclusive. the fact that not all studie ...201323493529
the effect of black tea and caffeine on regional cerebral blood flow measured with arterial spin labeling.black tea consumption has been shown to improve peripheral vascular function. its effect on brain vasculature is unknown, though tea contains small amounts of caffeine, a psychoactive substance known to influence cerebral blood flow (cbf). we investigated the effects on cbf due to the intake of tea components in 20 healthy men in a double-blinded, randomized, placebo-controlled study. on separate days, subjects received a single dose of 184 mg caffeine (equivalent to one strong espresso coffee), ...201323486295
inhibitory activity of green tea (camellia sinensis) extract on some clinically isolated cariogenic and periodontopathic bacteria.to determine the in vitro inhibitory activity of green tea extract on some clinically isolated cariogenic and periodontopathic bacteria.201323485656
characterization and activity of anthocyanins in zijuan tea (camellia sinensis var. kitamura).zijuan tea is a new cultivar produced in yunnan province of china. unlike most tea cultivars, zijuan tea is anthocyanin-rich. the composition and antioxidant activities of anthocyanins of zijuan tea were studied for the first time in this paper. anthocyanins were extracted with acidified methanol and quantified as 707 ± 28 μg/g of dry weight (cyanidin-3-o-β-d-glucoside equivalent) by high-performance liquid chromatography (hplc) analysis. four anthocyanins were successfully identified after ambe ...201323477682
serum urate levels and consumption of common beverages and alcohol among chinese in singapore.western studies suggest that beverages may affect serum urate (su) levels, but data from asian populations are scarce. we evaluated the associations between beverages and su levels in singaporean chinese.201323463601
development and validation of an efficient automated method for the analysis of 300 pesticides in foods using two-dimensional liquid chromatography-tandem mass spectrometry.in this study, a fully automated system was developed for the determination of more than 300 different pesticides from various food commodities. the samples were extracted with acetonitrile prior to the injection into the two-dimensional lc-system. no manual clean-up was needed. the separation of analytes and matrix compounds was carried out by a ymc-pack diol (2.1 mm×100 mm; 5 μm; 120å) hilic column in the first dimension. all analytes eluted within one small fraction at the beginning of the ru ...201323462110
doxorubicin cardiotoxicity and cardiac function improvement after stem cell therapy diagnosed by strain echocardiography.doxorubicin (dox) is one of the most effective chemotherapeutic agents; however, it causes dose-dependent cardiotoxicity. evaluation of left ventricular function relies on measurements based on m-mode echocardiography. a new technique based on quantification of myocardial motion and deformation, strain echocardiography, has been showed promising profile for early detection of cardiac dysfunction. different therapy strategies, such as flavonoid plant extracts and stem cells, have been investigate ...201323459697
effect of green tea (camellia sinensis) extract on healing process of surgical wounds in rat.green tea (camellia sinensis) has anti-oxidant and anti-inflammatory properties and may enhance wound healing process. the present study, therefore, was aimed to examine the effect of green tea ethanolic extract on wound healing process. for this experimental study, 36 healthy male wistar rats were randomly designated to three groups of a, b, and c which, respectively treated with, vaseline + 0.6% green tea extract, vaseline and normal saline for 21 days. wounds' length and area were measured by ...201323459184
tea and health: studies in humans.tea, next to water is the cheapest beverage humans consume. drinking the beverage tea has been considered a healthpromoting habit since ancient times. the modern medicinal research is providing a scientific basis for this belief. the evidence supporting the health benefits of tea drinking grows stronger with each new study that is published in the scientific literature. tea plant camellia sinensis has been cultivated for thousands of years and its leaves have been used for medicinal purposes. te ...201323448443
influence on longevity of blueberry, cinnamon, green and black tea, pomegranate, sesame, curcumin, morin, pycnogenol, quercetin, and taxifolin fed iso-calorically to long-lived, f1 hybrid mice.phytonutrients reportedly extend the life span of caenorhabditis elegans, drosophila, and mice. we tested extracts of blueberry, pomegranate, green and black tea, cinnamon, sesame, and french maritime pine bark (pycnogenol and taxifolin), as well as curcumin, morin, and quercetin for their effects on the life span of mice. while many of these phytonutrients reportedly extend the life span of model organisms, we found no significant effect on the life span of male f1 hybrid mice, even though the ...201323432089
green tea extract supplementation induces the lipolytic pathway, attenuates obesity, and reduces low-grade inflammation in mice fed a high-fat diet.the aim of this study was to evaluate the effects of green tea camellia sinensis extract on proinflammatory molecules and lipolytic protein levels in adipose tissue of diet-induced obese mice. animals were randomized into four groups: cw (chow diet and water); cg (chow diet and water + green tea extract); hw (high-fat diet and water); hg (high-fat diet and water + green tea extract). the mice were fed ad libitum with chow or high-fat diet and concomitantly supplemented (oral gavage) with 400 mg/ ...201323431242
biological clues to potent dna-damaging activities in food and flavoring.population differences in age-related diseases and cancer could stem from differences in diet. to characterize dna strand-breaking activities in selected foods/beverages, flavorings, and some of their constituent chemicals, we used p53r cells, a cellular assay sensitive to such breaks. substances testing positive included reference chemicals: quinacrine (peak response, 51×) and etoposide (33×); flavonoids: egcg (19×), curcumin (12×), apigenin (9×), and quercetin (7×); beverages: chamomile (11×), ...201323402862
purification, characterization and anticoagulant activity of the polysaccharides from green tea.the crude tea polysaccharides were extracted from the leaves of camellia sinensis using deionized water. the tea polysaccharides (tps) were further separated and purified by anion exchange chromatograph on deae sepharose cl-6b column to afford tps-1, tps-2, tps-3 and tps-4. the high performance gel permeation chromatograph analysis showed that the average molecular weight of polysaccharides (tps-1, tps-2 and tps-3) were 20,760, 24,230 and 250,643, respectively. tps-4 was 689, 113 and 4150, sugge ...201323399132
monitoring of some pesticides residue in consumed tea in tehran market.tea is an agricultural product of the leaves, leaf buds, and internodes of various cultivars and sub-varieties of the camellia sinensis plant, processed and vulcanized using various methods. tea is a main beverage in iranian food basket so should be free from toxic elements such as pesticides residue. there is no data bank on the residue of pesticides in the consumed black tea in iran. the present study is the first attempt for monitoring of 25 pesticide residues from different chemical groups i ...201323369650
correlation between catechin content and nf-κb inhibition by infusions of green and black tea.this study investigates whether infusions of green and black tea inhibit the nf-κb driven transcription in human epithelial gastric ags cells. water extracts were prepared from different brands of green and black tea available on the italian market. teas with or without caffeine were studied. an industrially prepared freeze-dried water extract of green tea was also tested. catechin and caffeine contents were measured by hplc analysis. the decrease in phenol and catechin content three months afte ...201323636906
neurochemical and behavioral effects of green tea (camellia sinensis): a model study.being rich in polyphenolic compounds such as flavonoids, green tea is suggested to be a potential candidate for the treatment of obesity, stress, depression, parkinson's and other disorders. since serotonin has an important role in the pathophysiology of these disorders, present study was designed to monitor the effects of green tea in rats. green tea extract was provided to the male albino wistar rats for 5 weeks, and effects on behaviors were monitored. results show a decrease in food intake a ...201323625424
protective effects of keemun black tea polysaccharides on acute carbon tetrachloride-caused oxidative hepatotoxicity in mice.this study was designed to investigate chemical characterization of the water-soluble polysaccharides extracted from keemun black tea (kbtp), and their antioxidant and hepatoprotective effects against ccl4-induced oxidative damage in mice. hplc analysis revealed that kbtp is the typical acidic heteropolysaccharides and consisted of nine monosaccharides. furthermore, kbtp showed highly ferric-reducing antioxidant power and scavenging effects against dpph, oh and o2(-) in vitro. administration of ...201323623843
chemical composition, plant secondary metabolites, and minerals of green and black teas and the effect of different tea-to-water ratios during their extraction on the composition of their spent leaves as potential additives for ruminants.this study characterized the chemical composition of green and black teas as well as their spent tea leaves (stl) following boiling in water with different tea-to-water ratios. the green and black tea leaves had statistically similar (g/kg dry matter (dm), unless stated otherwise) dm (937 vs 942 g/kg sample), crude protein (240 vs 242), and ash (61.8 vs 61.4), but green tea had significantly higher (g/kg dm) total phenols (231 vs 151), total tannins (204 vs 133), condensed tannins (176 vs 101), ...201323621359
two new oleanane-type triterpenes isolated from japanese post-fermented tea produced by anaerobic microbial fermentation.four triterpenes were isolated from a traditional japanese tea product produced by anaerobic microbial fermentation of heated green tea leaves (camellia sinensis). two of the compounds were novel and characterized by spectroscopic investigation to be 13,26-epoxy-3β,11α-dihydroxyolean-12-one and 3β,11α,13β-trihydroxyolean-12-one. two known triterpenes were identified as taraxastane-3β,20β-diol and taraxastane-3β,20α-diol. these triterpenes were not detected in the original green tea leaves.201323615533
impact of thearubigins on the estimation of total dietary flavonoids in the european prospective investigation into cancer and nutrition (epic) study.thearubigins (tr) are polymeric flavanol-derived compounds formed during the fermentation of tea leaves. comprising ∼70% of total polyphenols in black tea, tr may contribute majorly to its beneficial effects on health. to date, there is no appropriate food composition data on tr, although several studies have used data from the us department of agriculture (usda) database to estimate tr intakes. we aimed to estimate dietary tr in the european prospective investigation into cancer and nutrition ( ...201323612513
development of tea extracts and chitosan composite films for active packaging materials.the effects of 0.5%, 1% and 2% green tea extracts (gte) and black tea extracts (bte) on the physical, structural and antioxidant properties of chitosan films were investigated. results showed that the addition of tea extracts significantly decreased water vapour permeability and increased the antioxidant ability of films. the dpph radical scavenging ability of gte films was stronger than that of bte films in all food simulants (0%, 20%, 75% and 95% ethanol). the equilibration time in different f ...201323603075
evaluation of reproductive and developmental toxicities of pu-erh black tea (camellia sinensis var. assamica) extract in sprague dawley rats.pu-erh black tea, which is obtained by first parching crude green tea leaves and followed by secondary fermentation with microorganisms, has been believed to be beneficial beverages for health in pr china. but its potential toxicity when administered at a high dose as concentrated extract has not been completely investigated.201323602733
cross-sectional dietary deficiencies among a prison population in papua new guinea.to investigate the dietary adequacy of prisoners of beon prison, madang, papua new guinea in response to a report of possible nutritional deficiency.201323601963
selective speciation of inorganic antimony on tetraethylenepentamine bonded silica gel column and its determination by graphite furnace atomic absorption spectrometry.a speciation system for antimony (iii) and antimony (v) ions that based on solid phase extraction on tetraethylenepentamine bonded silica gel has been established. antimony was determined by graphite furnace atomic absorption spectrometry (gf-aas). analytical conditions including ph, sample volume, etc., were studied for the quantitative recoveries of sb (iii) and sb (v). matrix effects on the recovery were also investigated. the recovery values and detection limit for antimony (iii) at optimal ...201323598207
dose-response plasma appearance of green tea catechins in adults.tea is an infusion of the camellia sinensis leaves. the most prevalent bioactive compounds in green tea are catechins (c), which are of great interest for their potential health-promoting effects. however, metabolism and bioavailability of c are not fully understood.201323589502
inhibition of camellia sinensis (l.) o. kuntze on microcystis aeruginosa and isolation of the inhibition factors.low concentration of tea (camellia sinensis (l.) o. kuntze) was shown to inhibit the growth of the toxic cyanobacterium microcystis aeruginosa. the inhibition efficiency was 40% at 0.1 g dry tea/l and 90% at 0.2 g/l after a 12-day culture. all varieties of tea used in the test could inhibit microcystis growth, in which the inhibitory effect of green tea was greater than that of black tea. antialgal allelochemicals were isolated from tea by solvent extraction, gel-chromatography and high performa ...201323584804
flavonol glycosides with lipid accumulation inhibitory activity and simultaneous quantitative analysis of 15 polyphenols and caffeine in the flower buds of camellia sinensis from different regions by lcms.a simultaneous quantitative analytical method for 15 major polyphenols, e.g. five catechins (1-5) and 10 flavonols (6-15), as functional constituents in the extracts of "tea flowers", the flower buds of camellia sinensis (theaceae), has been developed. the content of caffeine (16), which showed similar chromatographic behaviour under the analytical conditions, was also determined. to approve the validity of the newly developed protocol, thirteen extracts of the plant's flower buds collected from ...201323578653
black tea lowers the rate of blood pressure variation: a randomized controlled trial.measures of blood pressure variation have been associated with cardiovascular disease and related outcomes. the regular consumption of black tea can lower blood pressure, but its effects on blood pressure variation have yet to be investigated.201323553154
chemopreventive and therapeutic potential of tea polyphenols in hepatocellular cancer.the prophylactic and therapeutic properties of tea have been attributed to green tea catechins and black tea theaflavins besides several other polyphenolic compounds. tea polyphenols possess potent antioxidant and antiinflammatory properties and modulate several signaling pathways. these biochemical facets of tea polyphenols are responsible for its anticancer properties. several lethal cancers, such as liver cancer, develop within a background of oxidative stress and inflammation. liver cancer, ...201323530632
analysis of the inhibition of pai-1 by metal theaflavin complexes and their degradation products.the inhibition of elements of the plasminogen activator system [urokinase (upa), tissue plasminogen activator (tpa) and plasminogen activator inhibitor-1 (pai-1)] plays an important role in human diseases. pai-1 is overexpressed in obesity and diabetes, and the inhibition of this protein has been postulated to alleviate the symptoms of both disorders. we found that two theaflavins (tfs) from black tea inhibit pai-1 and we suggest that the beneficial effects of drinking tea may be associated with ...201323525250
studies on black tea (camellia sinensis) extract as a potential antioxidant and a probable radioprotector.positive health effects of tea (camellia sinensis) on a wide range of physiological problems and diseases are well known and are in part due to its copious antioxidant content. the effect of black tea extract (bte), which is rich in polyphenolic antioxidants, against the consequences of radiation exposure has not been properly identified. the functional properties of bte were analyzed and its radioprotective effect on v79 cells was explored in the present study. bte scavenged free radicals and i ...201323519756
epimerization of green tea catechins during brewing does not affect the ability to poison human type ii topoisomerases.(-)-epigallocatechin gallate (egcg) is the most abundant and biologically active polyphenol in green tea (camellia sinensis) leaves, and many of its cellular effects are consistent with its actions as a topoisomerase ii poison. in contrast to genistein and several related bioflavonoids that act as interfacial poisons, egcg was the first bioflavonoid shown to act as a covalent topoisomerase ii poison. although studies routinely examine the effects of dietary phytochemicals on enzyme and cellular ...201323514406
black tea, green tea and risk of breast cancer: an update.previous meta-analysis indicated conflicting results in case-control versus cohort studies on the association of green tea with breast cancer risk, and conflicting results were also found in case-control versus cohort studies in another meta-analysis on the association of black tea with breast cancer risk. many studies were published after the previous meta-analysis. besides, the dose-response relationship of tea consumption with breast cancer risk is unclear. thus the association of tea consump ...201323750333
what is under the hump? mass spectrometry based analysis of complex mixtures in processed food--lessons from the characterisation of black tea thearubigins, coffee melanoidines and caramel.in this contribution we review our work on the characterisation of processed food. we review novel methods and analysis strategies developed to account for the composition of extraordinarily complex materials such as black tea thearubigins, coffee melanoidines and thermally treated carbohydrates. our methods are mainly based on modern mass spectrometry and are introduced and critically discussed. a series of novel previously unpublished data interpretation strategies are presented as well. final ...201323748630
the use of green tea extract in cosmetic formulations: not only an antioxidant active ingredient.green tea (gt) extracts contain polyphenols, known to be effective free radical scavengers, and other ingredients that could also provide benefits to the skin. this is a report on clinical studies using objective, noninvasive methods to evaluate the effects of cosmetic formulations containing gt. experimental formulations were supplemented or not (vehicle) with 6% camellia sinensis glycolic leaf extracts (gt). these formulations were applied to the forearm skin of 24 volunteers, and their effect ...201323742288
phenolics metabolism in boron-deficient tea [camellia sinensis (l.) o. kuntze] plants.modification in the metabolism of phenolic compounds under boron (b) deficiency conditions was studied in tea plants. plants were grown from seed, treated with low b in hydroponic medium under environmentally controlled conditions for six weeks. dry matter production and b content of plants were significantly declined under b deficiency conditions. boron starvation resulted in rising phenylalanine ammonia lyase activity in the young leaves and declining polyphenol oxidase activity in the roots. ...201323739888
application of green zero-valent iron nanoparticles to the remediation of soils contaminated with ibuprofen.zero-valent iron nanoparticles (nzvis) are often used in environmental remediation. their high surface area that is associated with their high reactivity makes them an excellent agent capable of transforming/degrading contaminants in soils and waters. due to the recent development of green methods for the production of nzvis, the use of this material became even more attractive. however, the knowledge of its capacity to degrade distinct types of contaminants is still scarce. the present work des ...201323738986
tea consumption and the risk of oral cancer incidence: a case-control study from china.to evaluate the relation of tea consumption with the risk of oral cancer incidence.201323731795
dietary flavonoid intake, black tea consumption, and risk of overall and advanced stage prostate cancer.flavonoids are natural antioxidants found in various foods, and a major source is black tea. some experimental evidence indicates that flavonoids could prevent prostate cancer. we investigated the associations between flavonoid intake, black tea consumption, and prostate cancer risk in the netherlands cohort study, which includes 58,279 men who provided detailed baseline information on several cancer risk factors. from 1986 to 2003, 3,362 prostate cancers were identified, including 1,164 advance ...201323722011
active extracts of black tea (camellia sinensis) induce apoptosis of pc-3 prostate cancer cells via mitochondrial dysfunction.cancer of the prostate gland is the most common invasive malignancy and the second leading cause of cancer-related death in human males. many studies have shown that black tea reduces the risk of several types of cancer. we studied the effects of active extracts of black tea and the black tea polyphenols theaflavins (tfs), on the cellular proliferation and mitochondria of the human prostate cancer cell line pc-3. our studies revealed that yinghong black tea extracts (ybt), assam black tea extrac ...201323715786
effect of tea (camellia sinensis) and olive (olea europaea l.) leaves extracts on male mice exposed to diazinon.the present study was aimed to evaluate the effects of tea and olive leaves extracts and their combination in male mice intoxicated with a sublethal concentration of diazinon. exposure of mice to 6.5 mg/kg body weight of diazinon for seven weeks resulted in statistical increases of serum alanine aminotransferase, aspartate aminotransferase, gamma glutamyl transferase, alkaline phosphatase, creatine kinase, creatinine, glucose, triglycerides, and cholesterol, while the value of serum total protei ...201323691503
zinc modulates drought-induced biochemical damages in tea [camellia sinensis (l) o kuntze].zinc (zn) is an essential micronutrient that affects the growth and productivity of tea plant. drought stress causes various biochemical and physiological damages in plants. the present study aims at understanding the role of zn in modulating drought stress induced growth and biochemical damages in tea plant. the results of the present investigation demonstrated that drought-induced decrease in relative water content (rwc), dry mass of leaf, and antioxidants such as ascorbate and glutathione in ...201323682650
ethosomes in hair dye products as carriers of the major compounds of black tea extracts.this study describes a novel carrier, the ethosome-based system, which is composed of non-ionic surfactants, ethanol, and water.201323676188
prevalence, awareness and risk factors of hypertension in a large cohort of iranian adult population.there is considerable variation in hypertension prevalence and awareness, and their correlates, across different geographic locations and ethnic groups. we performed this cross-sectional analysis on data from the golestan cohort study (gcs).201323673348
a review on botanical species and chemical compounds with appetite suppressing properties for body weight control.as obesity has reached epidemic proportions, the management of this global disease is of clinical importance. the availability and popularity of natural dietary supplements for the treatment of obesity has risen dramatically in recent years. the purpose of this paper was to review the effect of commonly available over the counter plant-derived supplements used to suppress appetite for obesity control and management. the data were obtained from the electronic databases pubmed, springerlink, googl ...201323666454
[a case-control study on tea consumption and the risk of lung cancer].to investigate the association between tea consumption and lung cancer.201323654095
cross-sectional and longitudinal associations of lifestyle factors with depressive symptoms in ≥ 53-year old taiwanese - results of an 8-year cohort study.the objective of this study is to determine the concurrent and longitudinal associations of lifestyle factors including smoking, alcohol drinking, betel quid chewing, tea (camellia sinensis) drinking and physical activity with depressive symptoms in older taiwanese.201323651861
bioactive-rich sideritis scardica tea (mountain tea) is as potent as camellia sinensis tea at inducing cellular antioxidant defences and preventing oxidative stress.in several countries, tea (hot-water infusions of dried camellia sinensis (cs) leaves) is a major source of antioxidant flavonoids, and its consumption has been associated with several favourable outcomes. other plants used for the preparation of herbal teas are sources of phenolic antioxidant compounds; among them sideritis scardica (ss) is used for the preparation of a popular drink throughout eastern and central europe. we have compared the effects of an ss extract to a cs extract in hepg2 ce ...201323649594
tissue-specific, development-dependent phenolic compounds accumulation profile and gene expression pattern in tea plant [camellia sinensis].phenolic compounds in tea plant [camellia sinensis (l.)] play a crucial role in dominating tea flavor and possess a number of key pharmacological benefits on human health. the present research aimed to study the profile of tissue-specific, development-dependent accumulation pattern of phenolic compounds in tea plant. a total of 50 phenolic compounds were identified qualitatively using liquid chromatography in tandem mass spectrometry technology. of which 29 phenolic compounds were quantified bas ...201323646127
prevention of chronic diseases by tea: possible mechanisms and human relevance.tea, made from leaves of the plant camellia sinensis, theaceae, has been used by humans for thousands of years, first as a medicinal herb and then as a beverage that is consumed widely. for the past 25 years, tea has been studied extensively for its beneficial health effects, including prevention of cancer, reduction of body weight, alleviation of metabolic syndrome, prevention of cardiovascular diseases, and protection against neurodegenerative diseases. whether these effects can be produced by ...201323642203
heterogeneous fenton-like oxidation of monochlorobenzene using green synthesis of iron nanoparticles.iron nanoparticles (fe nps) were synthesized using tea extracts as a catalyst for the fenton-like oxidation of monochlorobenzene (mcb), where 69%, 53%, and 39% of mcb were, respectively, degraded by fe nps synthesized using green tea extracts, oolong tea extracts, and black tea extracts. fe nps synthesized using green tea extracts (gt-fe nps) demonstrated the best degradation since green tea contains a high concentration of caffeine/polyphenols used as both reducing and capping agents in the syn ...201324034218
tea polyphenols as novel and potent inhibitory substances against renin activity.renin inhibitory activities of three tea products were investigated for the first time in this work. water extracts from fermented oolong and black tea showed strong renin inhibitory activities. by the means of ultrafiltration, gradient high performance liquid chromatography and spectroscopic analysis, four active compounds were separated from aqueous black tea extract and identified as theasinensin b, theasinensin c, strictinin, and a hexose sulfate with a galloyl moiety, which had ic50 values ...201324028635
variation of photosynthesis, fatty acid composition, atpase and acid phosphatase activities, and anatomical structure of two tea (camellia sinensis (l.) o. kuntze) cultivars in response to fluoride.the changes of photosynthetic parameters, water use efficiency (wue), fatty acid composition, chlorophyll (chl) content, malondialdehyde (mda) content, atpase and acid phosphatase activities, fluoride (f) content, and leaf anatomical structure of two tea cultivars, "pingyangtezao" (py) and "fudingdabai" (fd), after f treatments were investigated. the results show that net photosynthetic rate (p(n)), stomatal conductance (g(s)), and transpiration rate (e) significantly decreased in both cultivars ...201324023526
stability of a cosmetic multiple emulsion loaded with green tea extract.multiple emulsions are excellent and exciting potential systems for the delivery of useful cosmetic agents. the work describes stability of a multiple emulsion for cosmetic purpose, loaded with extract of camellia sinensis l. (theaceae) in concentration of 5%. the formulation constitutes of cetyl dimethicone copolyol and polyoxyethylene (20) cetyl ether as emulsifiers and was characterised and monitored for various physicochemical aspects. centrifugation has no devastating effect on physical des ...201324058284
quantitative analysis of catechin, flavonoid, and saponin constituents in "tea flower", the flower buds of camellia sinensis, from different regions in taiwan.using the recently developed two analytical protocols, distributions were analyzed of five catechins (1-5), ten flavonoids (6-15), caffeine (16), and nine saponins (17-25) in 12 samples of flower buds of camellia sinensis (l.) o. kuntze, collected at different points in taiwan. characteristic tendencies with respect to the distribution of these constituents were observed according to the region of collection. among the catechins, (-)-epigallocatechin 3-o-gallate (5) was the major constituent in ...201324427940
trace level voltammetric determination of heavy metals and total mercury in tea matrices (camellia sinensis).an analytical procedure regarding the voltammetric determination of mercury(ii), copper(ii), lead(ii), cadmium(ii) and zinc(ii) by square wave anodic stripping voltammetry (swasv) in matrices involved in food chain is proposed. in particular, tea leaves were analyzed as real samples. the digestion of each matrix was carried out using a concentrated hcl-hno3-h2so4 acidic attack mixture; 0.01 mol l(-1) edta-na2+ 0.15 mol l(-1) nacl + 0.5 mol l(-1) hcl was employed as the supporting electrolyte. th ...201324416778
effect of different drying methods on chemical composition and bioactivity of tea polysaccharides.four polysaccharides (tps-f, tps-v, tps-s and tps-m) were obtained from tea (camellia sinensis) leaves by freeze-drying, vacuum-drying, spray-drying and microwave-vacuum drying, respectively. their chemical composition and biological properties were comparatively studied. the results showed these tps were similar in ir, uv absorption and distribution of molecular weight. however, they showed significant differences (p<0.05) in yields of crude polysaccharides and contents of protein and total pol ...201324120964
effects of hibiscus sabdariffa l. on serum lipids: a systematic review and meta-analysis.prevention of cardiovascular disease by modifying its major risk factors, including serum cholesterol levels, is an important strategy. hibiscus sabdariffa l. has been promoted for reducing cholesterol levels, but its reported impact on cholesterol levels has been inconsistent. the study aimed to assess systematically the evidence and quality of current research on the effect of hibiscus sabdariffa l. on blood lipids and its adverse effects.201324120746
simultaneous determination of four aflatoxins and ochratoxin a in ginger and related products by hplc with fluorescence detection after immunoaffinity column clean-up and postcolumn photochemical derivatization.ginger, a widely used spice and traditional chinese medicine, is prone to be contaminated by mycotoxins. a simple, sensitive, and reproducible method based on immunoaffinity column clean-up coupled with hplc and on-line postcolumn photochemical derivatization with fluorescence detection was developed for the simultaneous determination of aflatoxins (afs) b1 , b2 , g1 , g2 , and ochratoxin a (ota) in 25 batches of gingers and related products marketed in china for the first time. the samples were ...201324115567
identification of mirnas and their targets in tea (camellia sinensis).micrornas (mirnas) are endogenous small rnas playing a crucial role in plant growth and development, as well as stress responses. among them, some are highly evolutionally conserved in the plant kingdom, this provide a powerful strategy for identifying mirnas in a new species. tea (camellia sinensis) is one of the most important commercial beverage crops in the world, but only a limited number of mirnas have been identified. in the present study, a total of 14 new c. sinensis mirnas were identif ...201324101208
purification, characterization and biological activities in vitro of polysaccharides extracted from tea seeds.three polysaccharide fractions (ntsps, atsps1-1 and atsps2) were isolated and purified from the water extract of tea (camellia sinensis) seeds with yields of 32.74%, 25.22%, and 11.09%, respectively. the average molecular weight of ntsps, atsps1-1 and atsps2 was determined by hpgpc system, with an mw of 4.588, 500 and 100 kda, respectively. monosaccharide analysis by ion chromatography revealed they differed from each other in monosaccharide kinds and molar ratio. furthermore, atsps1-1 and atsps ...201324099943
green tea (camellia sinensis) administration induces expression of immune relevant genes and biochemical parameters in rainbow trout (oncorhynchus mykiss).present study elucidates the efficacy of green tea (camellia sinensis) on growth performance, immune and antioxidant systems and cytokine gene expression in rainbow trout tissues. green tea was supplemented at 20, 100, and 500 mg kg(-1) diet and fed to fish (average weight: 23.5 g) for 35 days. no remarkable changes in growth performance were observed among all test groups. lower lipid peroxidation product and higher superoxide dismutase activity were noted in fish received the medium dose of gr ...201324096104
soluble antioxidant compounds regenerate the antioxidants bound to insoluble parts of foods.this study aimed to investigate the regeneration potential of antioxidant capacity of an insoluble food matrix. investigations were performed in vitro with several food matrices rich in dietary fiber (df) and bound antioxidants. after removal of the soluble fraction, the antioxidant capacity (ac) of the insoluble fraction was measured by the quencher procedure using abts(•+) or dpph(•) radicals. after measurement, the insoluble residue was washed out to remove the excess of radicals and treated ...201324093663
going green: the role of the green tea component egcg in chemoprevention.tea is one of the most consumed beverages worldwide, and green tea is the least processed from the buds of the camellia sinensis plant. the most abundant component of green tea is (-)-epigallocatechin-3-gallate (egcg), which has been the focus of many cell culture, animal and clinical trials, revealing that egcg possesses antiproliferative, antimutagenic, antioxidant, antibacterial, antiviral and chemopreventive effects. in this review we briefly summarize the mechanism of action(s) of the green ...201324077764
human studies on the absorption, distribution, metabolism, and excretion of tea polyphenols.recent research on the bioavailability of flavan-3-ols after ingestion of green tea by humans is reviewed. glucuronide, sulfate, and methyl metabolites of (epi)catechin and (epi)gallocatechin glucuronide reach peak nanomolar per liter plasma concentrations 1.6-2.3 h after intake, indicating absorption in the small intestine. the concentrations then decline, and only trace amounts remain 8 h after ingestion. urinary excretion of metabolites over a 24-h period after green tea consumption correspon ...201324172307
does tea prevent cancer? evidence from laboratory and human intervention studies.tea (camellia sinensis) is a widely consumed beverage and has been extensively studied for its cancer-preventive activity. both the polyphenolic constituents as well as the caffeine in tea have been implicated as potential cancer-preventive compounds; the relative importance seems to depend on the cancer type. green tea and the green tea catechin have been shown to inhibit tumorigenesis at a number of organ sites and to be effective when administered either during the initiation or postinitiatio ...201324172300
cellular targets for the beneficial actions of tea polyphenols.green and black teas contain different biologically active polyphenolic compounds that might offer protection against a variety of human diseases. although promising experimental and clinical data have shown protective effects, limited information is available on how these beneficial effects of tea polyphenols are mediated at the cellular level. evidence is accumulating that catechins in green tea as well as theaflavins and thearubigins from black tea are the substances responsible for the physi ...201324172299
interactions of black tea polyphenols with human gut microbiota: implications for gut and cardiovascular health.epidemiologic studies have convincingly associated consumption of black tea with reduced cardiovascular risk. research on the bioactive molecules has traditionally been focused on polyphenols, such as catechins. black tea polyphenols (btps), however, mainly consist of high-molecular-weight species that predominantly persist in the colon. there, they can undergo a wide range of bioconversions by the resident colonic microbiota but can in turn also modulate gut microbial diversity. the impact of b ...201324172295
time-resolved in-situ observation of starch polysaccharide degradation pathways.analytical challenges in the direct time-resolved observation of starch metabolism have been addressed by using optimized multidimensional nmr experiments. starch provides the main source of human dietary energy intake and is a raw material for beverage and renewable fuel production. use of direct in situ observations of starch remodeling pathways could facilitate our understanding and control of processes of biotechnological, medical, and environmental relevance. processes involving starch synt ...201324166781
graphite furnace atomic absorption spectrometric detection of vanadium in water and food samples after solid phase extraction on multiwalled carbon nanotubes.vanadium(v) ions as 8-hydroxyquinoline chelates were loaded on multiwalled carbon nanotubes (mwnts) in a mini chromatographic column. vanadium was determined by graphite furnace atomic absorption spectrometry (gfaas). various analytical parameters including ph of the working solutions, amounts of 8-hydroxyquinoline, eluent type, sample volume, and flow rates were investigated. the effects of matrix ions and some transition metals were also studied. the column can be reused 250 times without any ...201324148394
antimutagenic activity and preventive effect of black tea on buccal mucosa cancer.a black tea product was evaluated for anti-mutagenic and in vivo anticancer effects. at concentrations of 1.25 and 2.5 mg/plate, black tea exhibited anti-mutagenicity with n-methyl-n'-nitro-n-nitrosoguanidine (mnng) in the salmonella typhimurium ta100 strain. a kunming (km) mouse buccal mucosa cancer model was established by injecting mice with u14 squamous cell carcinoma cells. following injection, the wound at the injection site was smeared with black tea. it was observed that the tumor volume ...201324137377
identification of native catechin fatty acid esters in green tea (camellia sinensis).catechins are potent antioxidants and make up the primary class of polyphenols present in tea (camellia sinensis). they are especially abundant in the less-fermented green teas that have been employed in various foods to enhance shelf life stability (senanayake, n. j. funct. foods 2013, in press. gramza, a.; korczak, j. trends food sci. 2005, 16, 351-358). the antioxidative activity of native (polar) catechins has proven to be useful in foods of relatively high polarity, while mixed results have ...201324251649
green tea (camellia sinensis) supplementation to diabetic rats improves serum and hepatic oxidative stress markers.diabetes is one of the most common metabolic disorders and is interrelated to oxidative stress-induced diseases. according to the role of dietary antioxidants in control and prevention of diabetes, this study was aimed to evaluate the effect of green tea extract on serum glucose levels and serum and hepatic total antioxidant capacity (tac) and lipid (mda) in diabetic rats. experimental diabetes in rats was induced by intraperitoneal injection of streptozotocin (55 mg/kg). alcoholic extract of gr ...201324250578
oxidative stress reduced by a green tea concentrate and capsicum combination: synergistic effects.reactive oxygen species that are produced by aerobic metabolism and signaling cascades have the potential to play important roles in maintaining homeostatic redox and cell proliferation. when the balance between the production and elimination of reactive oxygen species is perturbed toward production, the result is oxidative stress. high levels of oxidative stress are a general characteristic of cancer. the altered redox state within a tumor microenvironment confers a growth advantage through inc ...201324237187
l-theanine (suntheanin): effects of l-theanine, an amino acid derived from camellia sinensis (green tea), on stress response parameters. 201324304633
floral transcriptome sequencing for ssr marker development and linkage map construction in the tea plant (camellia sinensis).despite the worldwide consumption and high economic importance of tea, the plant (camellia sinensis) is not well studied in molecular biology. under the few circumstances in which the plant is studied, c. sinensis flowers, which are important for reproduction and cross-breeding, receive less emphasis than investigation of its leaves or roots. using high-throughput illumina rna sequencing, we analyzed a c. sinensis floral transcriptome, and 26.9 million clean reads were assembled into 75,531 unig ...201324303059
dynamic changes in catechin levels and catechin biosynthesis-related gene expression in albino tea plants (camellia sinensis l.).tea (camellia sinensis (l.) o. kuntze) leaves are a major source of flavonoids that mainly belong to the flavan-3-ols or catechins and are implicated in a wide range of health benefits. although the catechins in tea leaves were identified long ago, the regulatory mechanisms governing catechin biosynthesis remain unclear. in the present work, the dynamic changes of catechin levels and the expression profiles of catechin-related genes in albino tea plants were intensively examined. the amounts of ...201323911731
amelioration of iron toxicity: a mechanism for aluminum-induced growth stimulation in tea plants.tea plants (camellia sinensis) are well adapted to acid soils with high al availability. these plants not only accumulate high leaf al concentrations, but also respond to al with growth stimulation. decreased oxidative stress has been associated with this effect. why tea plants not exposed to al suffer from oxidative stress has not been clarified. in this study, hydroponically grown tea plants treated with 0 to 300 μm al were analyzed for growth, al and fe accumulation, and al distribution by me ...201323910825
effect of kombucha, a fermented black tea in attenuating oxidative stress mediated tissue damage in alloxan induced diabetic rats.diabetic complications associated with increased oxidative stress can be suppressed by antioxidants. in the present study we investigated the antidiabetic and antioxidant effects of kombucha (kt), a fermented black tea, in comparison to that of unfermented black tea (bt), in alx-induced diabetic rats. alx exposure lowered the body weight and plasma insulin by about 28.12% and 61.34% respectively and elevated blood glucose level and glycated hb by about 3.79 and 3.73 folds respectively. the oxida ...201323907022
advanced phytochemical analysis of herbal tea in china.herbal tea is a commonly consumed beverage brewed from the leaves, flowers, seeds, fruits, stems and roots of plants species rather than camellia sinensis l., which has been widely used for health care and diseases prevention for centuries. with the increasing consumption of herbal tea, a number of public health issues e.g., efficacy, safety and quality assurance have attracted concern. however, to date, there is no a review focus on herbal tea. phytochemical analysis, as a key step to investiga ...201323906802
comparison of the dissipation behaviour of three neonicotinoid insecticides in tea.the dissipation behaviour of three neonicotinoids - thiamethoxam, imidacloprid and acetamiprid - was compared in tea shoots, in chinese green and black tea, and after tea infusion in hot water. the simple and rapid analytical procedures for the quantification of these three residues in these matrices were developed using hplc with ultraviolet (uv) detection. degradation rates in tea shoots of neonicotinoids applied in either recommended or double dosages followed first-order kinetics, with half- ...201323906092
effect of repeated wuniu early tea administration on the cyp450 activity using a cocktail method.wuniu early tea (camellia sinensis) is an important beverage consumed in china. up to date, a lot of methods for identifying and chemical analysing have been done. however, there is no report on the effects of wuniu early tea on cytochrome p450 isozymes. therefore, the present objective of our study was to evaluate the potential effects of wuniu early tea on cytochrome p450 isozymes p2c9, p1a2, p2c19 and p2b6 in rats with a cocktail approach including, matching probe drugs of tolbutamide, phenac ...201323901167
[application of black tea as a negative oral contrast in magnetic resonance cholangiopancreatography (mrcp)].to investigate the feasibility of using black tea as a gastrointestinal oral negative contrast agent to null the signal from fluid in bowel during mr cholangiopancreatography (mrcp).201323898539
treatment of oral mucositis in hematologic patients undergoing autologous or allogeneic transplantation of peripheral blood stem cells: a prospective, randomized study with a mouthwash containing camelia sinensis leaf extract.oral mucositis is an important side effect of hematopoietic stem cell transplantation (hcst), mainly due to toxicity of conditioning regimens. it produces significant pain and morbidity. the present study reports a prospective, randomized, non-blinded study testing the efficacy of a new mouthwash, called baxidil onco(®) (sanitas farmaceutici srl, tortona, italy) in 60 hematologic patients undergoing hcst (28 autologous, 32 allogeneic). baxidil onco(®), used three times a day from day -1 to day + ...201323888242
chromatographic analysis of methylglyoxal and other α-dicarbonyls using gas-diffusion microextraction.many α-dicarbonyl compounds such as methylglyoxal, diacetyl and pentane-2,3-dione are important quality markers of processed foods. they are produced by enzymatic and chemical processes, the maillard reaction is the most known chemical route for α-dicarbonyl formation. in the case of methylglyoxal, there are obstacles to be overcome when analysing this compound due to its high reactivity, low volatility and low concentration. the use of extraction techniques based on the volatilization of methyl ...201323883921
in vitro hypoglycaemic and hypolipidemic potential of white tea polyphenols.the leaves at different processing stages of a single tea cultivar in order to obtain white (wt), green (gt) and black tea (bt) samples, were analysed. the capacities of tea polyphenolics to influence the glucose and lipid metabolism in hepg2 cell lines were evaluated. wt appeared the most active in reducing the glucose and cholesterol uptake (+17.7% and +32.4% in the glucose and cholesterol cell medium concentration, respectively). incubation with wt enhanced ldl receptor binding activity by 40 ...201323870971
monitoring tea fermentation/manufacturing by direct analysis in real time (dart) mass spectrometry.factors such as fermentation methods, geographical origin and season can affect the biochemical composition of tea leaves (camellia sinensis l.). in this study, the biochemical composition of oolong tea during the manufacturing and fermentation process was studied using a non-targeted method utilising ambient ionisation with a direct analysis in real time (dart) ion source and mass spectrometry (ms). caffeine dominated the positive ionisation spectra throughout the manufacturing process, while t ...201323870928
the effect of camellia sinensis on wound healing potential in an animal model.camellia sinensis (tea) is reported to have health benefits, including the building of healthy skin. this study evaluated the effects of topical application of camellia sinensis extract on the rate of wound closure and the histology of wound area. a uniform area of 2.00 cm in diameter was excised from the neck of adult male sprague dawley rats. the animals were topically treated with 0.2 ml of vehicle (cmc), intrasite gel (positive control), or 200 and 400 mg/ml of extract. wounds dressed with t ...201323864889
screening of tea (camellia sinensis) for trait-associated molecular markers.this study was done to identify random amplified polymorphic dna (rapd) markers that may associate with seven important traits in tea. sixty rapd primers were first screened using 18 cultivars under each of the 7 traits, followed by confirmatory screening of 20 promising primers with 32 tea cultivars. six rapd primers generated a total of nine specific bands that associated with six desired traits: black tea quality and tolerance to drought, high temperature, low temperature, phomopsis theae, an ...201323852798
genoprotection and genotoxicity of green tea (camellia sinensis): are they two sides of the same redox coin?regular intake of green tea associates with lower dna damage and increased resistance of dna to oxidant challenge. however, in vitro pro-oxidant effects of green tea have been reported. both effects could be mediated by hydrogen peroxide (h2o2) which is generated by autoxidation of tea catechins. in large amounts, h2o2 is genotoxic, but low concentrations could activate the redox-sensitive antioxidant response element (are) via the keap-1/nrf2 redox switch, inducing genoprotective adaptations. o ...201323849339
green tea catechins: defensive role in cardiovascular disorders.green tea, camellia sinensis (theaceae), a major source of flavonoids such as catechins, has recently shown multiple cardiovascular health benefits through various experimental and clinical studies. these studies suggest that green tea catechins prevent the incidence of detrimental cardiovascular events, and also lower the cardiovascular mortality rate. catechins present in green tea have the ability to prevent atherosclerosis, hypertension, endothelial dysfunction, ischemic heart diseases, card ...201323845542
a comparative study of volatile components in green, oolong and black teas by using comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometry and multivariate data analysis.the difference of volatile components in green, oolong and black teas was studied by using comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometry (gc×gc-tofms). simultaneous distillation extraction was proved to be a suitable technique to extract the analytes with interest. a total of 450 compounds were tentatively identified with comparison to the standard mass spectra in available databases, retention index on the first dimension and structured chromatogram. 33 tea s ...201323838302
fuzhuanins a and b: the b-ring fission lactones of flavan-3-ols from fuzhuan brick-tea.fuzhuan brick-tea is a special dark tea prepared from the leaves of camellia sinensis var. sinensis. its production involves a fungal fermentation stage, which forms the unique flavors and functions by a series of biochemical reactions. our phytochemical research of the material led to the isolation of two new b-ring fission lactones of flavan-3-ols, fuzhuanins a (1) and b (2). in addition, three other flavan-3-ol derivatives (3-5), three flavone c-glycosides (6-8), eight flavonoid o-glycosides ...201323837839
a hair growth-promoting effect of chinese black tea extract in mice.chinese black tea extract (cbte) fermented with aspergillus sp. significantly promoted hair growth after 2 weeks of topical application in shaved 6 week-old male c3h/he mice. the hair growth-promoting effect of cbte was potentiated synergistically by capsaicin, which has no effect on hair growth by itself. cbte displayed an affinity for estrogen receptor (er)α, with an ic50 value of 74.8 µg/ml. this effect of cbte might be mediated by the ers, since a similar effect induced by orally administere ...201323832356
adsorption of methylene blue onto activated carbon produced from tea (camellia sinensis l.) seed shells: kinetics, equilibrium, and thermodynamics studies.tea (camellia sinensis l.) seed shells, the main byproduct of the manufacture of tea seed oil, were used as precursors for the preparation of tea activated carbon (tac) in the present study. a high yield (44.1%) of tac was obtained from tea seed shells via a one-step chemical method using zncl2 as an agent. the brunauer-emmett-teller (bet) surface area and the total pore volumes of the obtained tac were found to be 1530.67 mg(2)/g and 0.7826 cm(3)/g, respectively. the equilibrium adsorption resu ...201323825151
transgenic tobacco overexpressing tea cdna encoding dihydroflavonol 4-reductase and anthocyanidin reductase induces early flowering and provides biotic stress tolerance.flavan-3-ols contribute significantly to flavonoid content of tea (camellia sinensis l.). dihydroflavonol 4-reductase (dfr) and anthocyanidin reductase (anr) are known to be key regulatory enzymes of flavan-3-ols biosynthesis. in this study, we have generated the transgenic tobacco overexpressing individually tea cdna csdfr and csanr encoding for dfr and anr to evaluate their influence on developmental and protective abilities of plant against biotic stress. the transgenic lines of csdfr and csa ...201323823500
effect of increasing levels of zinc fortificant on the iron absorption of bread co-fortified with iron and zinc consumed with a black tea.iron (fe) and zinc's (zn) interaction at the absorptive level can have an effect on the success of co-fortification of wheat flour with both minerals on iron deficiency prevention. the aim of the study was to determine the effect of increasing levels of zinc fortificant on the iron absorption of bread co-fortified with iron and zinc consumed with a black tea. twelve women aged 33-42 years participated in the study. they received on four different days 200 ml of black tea and 100 g of bread made ...201323821315
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