Tea: The infusion of leaves of CAMELLIA SINENSIS (formerly Thea sinensis) as a beverage, the familiar Asian tea, which contains CATECHIN (especially epigallocatechin gallate) and CAFFEINE.Camellia sinensis: Camellia sinensis L. (formerly Thea sinensis) is an evergreen Asiatic shrub of the THEACEAE family. The infusion of leaves of this plant is used as Oriental TEA which contains CAFFEINE; THEOPHYLLINE; and epigallocatechin gallate.Catechin: An antioxidant flavonoid, occurring especially in woody plants as both (+)-catechin and (-)-epicatechin (cis) forms.Tea Tree Oil: Essential oil extracted from Melaleuca alternifolia (tea tree). It is used as a topical antimicrobial due to the presence of terpineol.Polyphenols: A large class of organic compounds having more than one PHENOL group.Phenols: Benzene derivatives that include one or more hydroxyl groups attached to the ring structure.Tetraethylammonium: A potassium-selective ion channel blocker. (From J Gen Phys 1994;104(1):173-90)Plant Extracts: Concentrated pharmaceutical preparations of plants obtained by removing active constituents with a suitable solvent, which is evaporated away, and adjusting the residue to a prescribed standard.Tetraethylammonium CompoundsBeverages: Liquids that are suitable for drinking. (From Merriam Webster Collegiate Dictionary, 10th ed)Flavonoids: A group of phenyl benzopyrans named for having structures like FLAVONES.Coffee: A beverage made from ground COFFEA beans (SEEDS) infused in hot water. It generally contains CAFFEINE and THEOPHYLLINE unless it is decaffeinated.Biflavonoids: Dimers (homo and hetero) of FLAVONOIDS.Gallic Acid: A colorless or slightly yellow crystalline compound obtained from nutgalls. It is used in photography, pharmaceuticals, and as an analytical reagent.Anticarcinogenic Agents: Agents that reduce the frequency or rate of spontaneous or induced tumors independently of the mechanism involved.Phytotherapy: Use of plants or herbs to treat diseases or to alleviate pain.

*  Learn About Green Tea - Buy Green Tea Supplements - Nutrition Express
Green tea boosts metabolism and increases fat burning*. Green tea has become a very popular ingredient in weight loss formulas ... A green tea catechin called epigallocatechin gallate (EGCG), when combined with caffeine, was shown to boost metabolism beyond ... Green tea protects the brain Green tea boosts fat burning Green tea targets belly fat Lose fat and weight with green tea Green ... Green tea extract may reduce body fat and improve endurance Weight loss and green tea: stirring the (tea) pot Burn fat with ...
*  Tea It Up
Green tea has more of this compound than other teas because of how it is processed. Black and oolong tea are made from ... Green tea supplements in pill form are not the same thing as brewing and drinking tea. The research is done on the actual tea, ... but black tea is also very good! Both green tea and black tea are full of flavonoids, a type of antioxidant of antioxidant that ... Do you need to buy specialty tea or is grocery store tea in the bag just fine? What kind of nutrients does it have and how much ...
*  OZslimmingtea provides healthy tea leaves that are effective for weight loss: Lawrence Mease Releases
OZ slimming tea has come up with loose tea leaves that are pure and are very effective when it comes to weight loss. The tea ... This kind of tea tends to be strong in taste when compared with the cooked tea removes the toxins that could harm the health. ... Healthy tea are ones that are finely broken and are not steeped into the bags. Fresh loose tea tends to provide better taste ... OZslimming tea is a company based in Australia and has been providing loose tea for a long time. They have come up with ...
*  Full text of "The book of tea"
The Schools of Tea The three stages of the evolution of Tea - The Boiled Tea, the Whipped Tea, and the Steeped Tea, ... The tea- room is made for the tea-master, not the tea-master for the tea-room. It is not intended for posterity and is there- ... who with tea amused the evening, with tea solaced the midnight, and with tea Bvelcomed the morning." 17 THE BOOK OF TEA Charles ... Full text of "The book of tea" See other formats # THE BOOK OF TEA I THE BOOK OF TEA Cv^- BY OKAKURA-KAKUZO G. P. PUTNAM'S SONS ...
*  Medical Advisor Journals, Kyle J. Norton Site, Health Tips for Better Living and Living Health: Green tea on weight maintenance
1) "Effects of green tea on weight maintenance after body-weight loss" by Kovacs EM, Lejeune MP, Nijs I, Westerterp-Plantenga ... In the investigation of whether green tea may improve weight maintenance by preventing or limiting weight regain after weight ... The result showed that in the green tea treatment, habitual high caffeine consumption was associated with a higher weight ... of 4 weeks followed by a weight-maintenance period of 13 weeks in which the subjects received green tea or placebo. ...
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Absorption Omega-3 Oils Daily Essential Fatty Acids Green Tea Fat Metabolizer combines a highly concentrated form of green tea ... Green Tea Fat Metabolizer maximizes powerful thermogenic action in fast-acting Liquid Soft-Gels.* For optimum results, use in ... The thermogenic combination of green tea extract and natural caffeine, while not actually melting fat, helps to oxidize fat and ... Green Tea Fat Metabolizer 150 Softgels Kick Start Your Fat Burning Ability* BioPerine Enhanced ...
*  Do green tea weight loss supplements work - moscowtorex.ru
Green tea is prepared by steaming and pan-frying these leaves and then drying them. Other teas such as black tea and oolong tea ... Consuming green tea or taking green tea extract containing to mg of green tea catechins, an antioxidant found in green tea, ... GREEN TEA AND CAFFEINE DIET PILLS - REVIEW. Does green tea help you lose weight? More specifically, does Mega T Green Tea help ... people drink green tea as a beverage. How does it work? The effect of green tea on weight loss seems to be Green tea extract ...
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*  Pennsylvania Tea Parties
Join your fellow Pennsylvania Tea Party activists and start a discussion or post an announcement of your local event. ... Pennsylvania Tea Parties is a Restricted Group with 64 members.. *Pennsylvania Tea Parties ...
*  Tea Party protests - Wikipedia
For protests in colonial America, see Boston Tea Party, Chestertown Tea Party, Edenton Tea Party and Philadelphia Tea Party. ... "Time for a Tea Party", The Washington Times, July 3, 2009.. *^ "TEA Party activists rally at Capitol - CNN.com". CNN. July 4, ... "Tea Party Attendance 268,000+". MSNBC. April 16, 2009.. *^ a b "Tea Party Nonpartisan Attendance Estimates: Now 300,000+". ... Signs of the Tea-Party Protests, photo essay by Time magazine. *"12 Tea Party leaders to watch", National Journal, February 4, ...
*  Boston Tea Party - Wikipedia
Heiss, Mary Lou; Heiss, Robert .J (2007). "A History of Tea: The Boston Tea Party". The Story of Tea: A Cultural History and ... Because the Tea Act made legally imported tea cheaper, it threatened to put smugglers of Dutch tea out of business.[44] ... John Adams and many other Americans considered tea drinking to be unpatriotic following the Boston Tea Party. Tea drinking ... Labaree, Tea Party, 6-7.. *^ Labaree, Tea Party, 13; Thomas, Townshend Duties, 26-27. This kind of refund or rebate is known as ...
*  Earnings Tea Leaves
Earnings season is here again. There are company estimates, consensus numbers and actual numbers being reported daily. From the beginning to end, they vary greatly. Christine Short, associate director at S&P Capital IQ, said third quarter estimates for S&P 500 … Continue reading →
*  Tea - Baltimore Sun
... or tea) as her family completes the registration process at the Ifo refugee settlement in Kenya's Dadaab Refugee Camp. ... A child drinks from a cup of chai (or tea) as her family completes the registration process at the Ifo refugee settlement in ... A child drinks from a cup of chai (or tea) as her family completes the registration process at the Ifo refugee settlement in ... A child drinks from a cup of chai (or tea) as her family completes the registration process at the Ifo refugee settlement in ...
*  Tea leaf grading - Wikipedia
"Tea grades". Tea grades. House of Tea. Retrieved 14 November 2012.. *^ Campbell Ronald Harlers (1973), ""Tea Production"", The ... "Peet's Coffee & Teas. Retrieved 2006-12-12.. *^ Barnes & Watson Fine Teas (2006). "Leaf Grades". Barnes & Watson Fine Teas. ... In the tea industry, tea leaf grading is the process of evaluating products based on the quality and condition of the tea ... Olde Wyndham Tea Company (2002). "Grades of Gourmet Tea". Olde Wyndham Tea Company. Archived from the original on 2006-12-09. ...
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*  Tocklai Tea Research Institute - Wikipedia
The beginning of a new era of tea research in India was marked by the establishment of the Scientific Department of Indian Tea ... Tocklai Tea Research Institute. টোকলাই চাহ গৱেষণা কেন্দ্ৰ. Tocklai Tea Research Institute ... Research on all aspects of tea cultivation and processing is carried out at the Tocklai Tea Research Institute, Jorhat, the ... Tocklai Tea Research Institute TRA [1]. This article about a scientific organization is a stub. You can help Wikipedia by ...
*  Tea fungus
Has anyone tasted such tea? I know that ordinary black tea (or red tea or orange tea) is made with the tea plant's own ... Tea fungus. George W. Chang changlab at nature.berkeley.edu Thu Aug 18 21:55:40 EST 1994 *Previous message: Tea fungus ... tea fungus' used to ferment cold sweetened black tea , to a supposedly extraordinary beverage. , , All I can recall is that it ... However the cake-like 'Puh Er' or 'Poo Nay' tea has a decided actinomycete taste. Does anyone know what is responsible for that ...
*  North Bengal Tea Industry - Wikipedia
Darjeeling tea Tea Board of India Indian Tea Association Assam Tea "Cold weather clouds tea crop prospects in Assam, Bengal". ... The youngest tea gardens are Chinchula Tea Estate,Raimatang Tea Estate and Kalchini Tea Estate all of which are 72 years old. ... The largest tea garden is Samsing Tea Estate of 1256.60 hectares. Most of the tea gardens in the Dooars region are members of ... Bought-leaf factories are units that buy these tea leaves and convert them into the processed tea. Generally, 6000 tea bushes ...
*  Clip art - Tea 8: Animations
Tea 8: Animations. Please note: If you arrived at this page direct from a search engine or other web site, please see the Cat- ... All users must post a prominent linkback or credit to Cat-Tea Clips on their web sites or other materials. ... All materials contained herein Copyright 1997-2006 The Cat-Tea Corner/JPB unless otherwise noted. All rights reserved. For ... Send us your URL to list here under our Web sites decorated with Cat-Tea Clips. ...
*  Labrador tea | plant | Britannica.com
Labrador tea: Common name for two species of low-growing, perennial evergreen shrubs in the Rhododendron genus of the heath ... Labrador tea, common name for two species of low-growing, perennial evergreen shrubs in the Rhododendron genus of the heath ... The fragrant leaves, which are sometimes used for making tea, are smooth-edged and elliptical and have a rusty "wool" on the ...
*  Category:Krasnodar tea - Wikimedia Commons
Media in category "Krasnodar tea". The following 2 files are in this category, out of 2 total. ... Retrieved from "https://commons.wikimedia.org/w/index.php?title=Category:Krasnodar_tea&oldid=192265167" ...
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(1/1351) ESR study on the structure-antioxidant activity relationship of tea catechins and their epimers.

The purpose of this study is to examine the relationship between the free radical scavenging activities and the chemical structures of tea catechins ((-)-epigallocatechin gallate (EGCG), (-)-epigallocatechin (EGC) and (-)-epicatechin (EC)) and their corresponding epimers ((-)-gallocatechin gallate (GCG), (-)-gallocatechin (GC) and (+)-catechin ((+)-C)). With electron spin resonance (ESR) we investigated their scavenging effects on superoxide anions (O-.2) generated in the irradiated riboflavin system, singlet oxygen(1O2) generated in the photoradiation-hemoporphyrin system, the free radicals generated from 2,2'-azobis(2-amidinopropane)hydrochloride (AAPH) and 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radical. The results showed that the scavenging effects of galloylated catechins (EGCG and GCG) on the four free radicals were stronger than those of nongalloylated catechins (EGC, GC, EC, (+)-C), and the scavenging effects of EGC and GC were stronger than those of EC and (+)-C. Thus, it is suggested that the presence of the gallate group at the 3 position plays the most important role in their free radical-scavenging abilities and an additional insertion of the hydroxyl group at the 5' position in the B ring also contributes to their scavenging activities. Moreover, the corresponding phenoxyl radicals formed after the reaction with O-.2 were trapped by DMPO and the ESR spectra of DMPO/phenoxyl radical adducts were observed (aN=15.6 G and aHbeta=21.5 G). No significant differences were found between the scavenging effects of the catechins and their epimers when their concentrations were high. However, significant differences were observed at relatively low concentrations, and the lower their concentrations, the higher the differences. The scavenging abilities of GCG, GC and (+)-C were stronger than those of their corresponding epimers (EGCG, EGC and EC). The differences between their sterical structures played a more important role in their abilities to scavenge large free radicals, such as the free radicals generated from AAPH and the DPPH radical, than to scavenge small free radicals, such as O-.2 and 1O2, especially in the case with EGCG and GCG with more bulky steric hindrance.  (+info)

(2/1351) 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, followed by a steady decrease. There was also slight incorporation of the label into 7-methylxanthine, serine, glutamate and aspartate, disappearing by 36 h after the absorption of L-[Me-14C]methionine. 3. The radioactivities of nucleic acids derived from L-[Me-14C]methionine increased rapidly during the first 12 h incubation period and then decreased steadily. Sedimentation analysis of nucleic acids by sucrose-gradient centrifugation showed that methylation of nucleic acids in tea shoot tips occurred mainly in the tRNA fraction. The main product among the methylated bases in tea shoot tips was identified as 1-methyladenine. 4. The results indicated that the purine ring in caffeine is derived from the purine nucleotides in the nucleotide pool rather than in nucleic acids. A metabolic scheme to show the production of caffeine and related methylxanthines from the nucleotides in tea plants is discussed.  (+info)

(3/1351) Inhibition of benzo[a]pyrene-induced mutagenesis by (-)-epigallocatechin gallate in the lung of rpsL transgenic mice.

Epigallocatechin gallate (EGCG) is a major water-soluble component of green tea. The antimutagenic activity of EGCG against benzo[a]pyrene (B[a]P)-induced mutations was assessed by using transgenic mice carrying the rpsL gene as a monitor of mutations. Seven-week-old male mice were given drinking water containing EGCG for 3 weeks. On day 7, mice were treated with a single i.p. injection of B[a]P (500 mg/kg body wt). Two weeks after the injection, the mutations in the rpsL gene were analyzed. B[a]P treatment resulted in an approximately 4-fold increase of mutation frequency at the rpsL gene in the lung. An approximately 60% reduction in the B[a]P-induced mutations in the lung was observed when mice were given EGCG at concentrations >0.005%. B[a]P-induced mutations mainly occurred at G:C basepairs in the several specific nucleotide sequences of the rpsL gene. These were AGG, CGG, CGT, TGG, TGC and GGT: all of them contained a guanine residue. Mutations seen similarly in the human Ki-ras codon 12 or p53 codons 157, 248, and 273 of lung tumor were also found in the rpsL gene, and the mutations were suppressed by the EGCG treatment. In conclusion, the antimutagenic effects of EGCG for B[a]P-induced mutagenesis in vivo suggest that drinking green tea may reduce the tumor-initiating potency of B[a]P in the lung.  (+info)

(4/1351) Methylation of tea catechins by rat liver homogenates.

Methylation of (-)-epigallocatechin (EGC), (-)-epicatechin gallate (ECg), and (-)-epigallocatechin gallate (EGCg) was carried out with a rat liver homogenate and S-adenosyl-L-methionine. A structural analysis of the reaction products by MS and NMR showed that 4'-O-methyl EGC, 4"-O-methyl ECg, and 4"-O-methyl EGCg had been formed from EGC, ECg, and EGCg, respectively. These results suggest that methylation may be one of the metabolic pathways to the catechins.  (+info)

(5/1351) Epigallocathechin-3 gallate selectively inhibits the PDGF-BB-induced intracellular signaling transduction pathway in vascular smooth muscle cells and inhibits transformation of sis-transfected NIH 3T3 fibroblasts and human glioblastoma cells (A172).

Enhanced activity of receptor tyrosine kinases such as the PDGF beta-receptor and EGF receptor has been implicated as a contributing factor in the development of malignant and nonmalignant proliferative diseases such as cancer and atherosclerosis. Several epidemiological studies suggest that green tea may prevent the development of cancer and atherosclerosis. One of the major constituents of green tea is the polyphenol epigallocathechin-3 gallate (EGCG). In an attempt to offer a possible explanation for the anti-cancer and anti-atherosclerotic activity of EGCG, we examined the effect of EGCG on the PDGF-BB-, EGF-, angiotensin II-, and FCS-induced activation of the 44 kDa and 42 kDa mitogen-activated protein (MAP) kinase isoforms (p44(mapk)/p42(mapk)) in cultured vascular smooth muscle cells (VSMCs) from rat aorta. VSMCs were treated with EGCG (1-100 microM) for 24 h and stimulated with the above mentioned agonists for different time periods. Stimulation of the p44(mapk)/p42(mapk) was detected by the enhanced Western blotting method using phospho-specific MAP kinase antibodies that recognized the Tyr204-phosphorylated (active) isoforms. Treatment of VSMCs with 10 and 50 microM EGCG resulted in an 80% and a complete inhibition of the PDGF-BB-induced activation of MAP kinase isoforms, respectively. In striking contrast, EGCG (1-100 microM) did not influence MAP kinase activation by EGF, angiotensin II, and FCS. Similarly, the maximal effect of PDGF-BB on the c-fos and egr-1 mRNA expression as well as on intracellular free Ca2+ concentration was completely inhibited in EGCG-treated VSMCs, whereas the effect of EGF was not affected. Quantification of the immunoprecipitated tyrosine-phosphorylated PDGF-Rbeta, phosphatidylinositol 3'-kinase, and phospholipase C-gamma1 by the enhanced Western blotting method revealed that EGCG treatment effectively inhibits tyrosine phosphorylation of these kinases in VSMCs. Furthermore, we show that spheroid formation of human glioblastoma cells (A172) and colony formation of sis-transfected NIH 3T3 cells in semisolid agar are completely inhibited by 20-50 microM EGCG. Our findings demonstrate that EGCG is a selective inhibitor of the tyrosine phosphorylation of PDGF-Rbeta and its downstream signaling pathway. The present findings may partly explain the anti-cancer and anti-atherosclerotic activity of green tea.  (+info)

(6/1351) Prevention of collagen-induced arthritis in mice by a polyphenolic fraction from green tea.

Identification of common dietary substances capable of affording protection or modulating the onset and severity of arthritis may have important human health implications. An antioxidant-rich polyphenolic fraction isolated from green tea (green tea polyphenols, GTPs) has been shown to possess anti-inflammatory and anticarcinogenic properties in experimental animals. In this study we determined the effect of oral consumption of GTP on collagen-induced arthritis in mice. In three independent experiments mice given GTP in water exhibited significantly reduced incidence of arthritis (33% to 50%) as compared with mice not given GTP in water (84% to 100%). The arthritis index also was significantly lower in GTP-fed animals. Western blot analysis showed a marked reduction in the expression of inflammatory mediators such as cyclooxygenase 2, IFN-gamma, and tumor necrosis factor alpha in arthritic joints of GTP-fed mice. Histologic and immunohistochemical analysis of the arthritic joints in GTP-fed mice demonstrated only marginal joint infiltration by IFN-gamma and tumor necrosis factor alpha-producing cells as opposed to massive cellular infiltration and fully developed pannus in arthritic joints of non-GTP-fed mice. The neutral endopeptidase activity was approximately 7-fold higher in arthritic joints of non-GTP-fed mice in comparison to nonarthritic joints of unimmunized mice whereas it was only 2-fold higher in the arthritic joints of GTP-fed mice. Additionally, total IgG and type II collagen-specific IgG levels were lower in serum and arthritic joints of GTP-fed mice. Taken together our studies suggest that a polyphenolic fraction from green tea that is rich in antioxidants may be useful in the prevention of onset and severity of arthritis.  (+info)

(7/1351) Cancer chemopreventive mechanisms of tea against heterocyclic amine mutagens from cooked meat.

Cooking meat and fish under normal conditions produces heterocyclic amine mutagens, several of which have been shown to induce colon tumors in experimental animals. In our search for natural dietary components that might protect against these mutagens, it was found that green tea and black tea inhibit the formation of heterocyclic amine-induced colonic aberrant crypt foci (ACF) in the rat. Since ACF are considered to be putative preneoplastic lesions, we examined the inhibitory mechanisms of tea against the heterocyclic amines. In the initial studies using the Salmonella mutagenicity assay, green tea and black tea inhibited according to the concentration of tea leaves during brewing and the time of brewing; a 2-3-min brew of 5% green tea (w/v) was sufficient for >90% antimutagenic activity. N-hydroxylated heterocyclic amines, which are direct-acting mutagens in Salmonella, were inhibited by complete tea beverage and by individual components of tea, such as epigallocatechin-3-gallate (EGCG). Inhibition did not involve enhanced mutagen degradation, and EGCG and other catechins complexed only weakly with the mutagens, suggesting electrophile scavenging as an alternative mechanism. Enzymes that contribute to the metabolic activation of heterocyclic amines, namely microsomal NADPH-cytochrome P450 reductase and N, O-acetyltransferase, were inhibited by tea in vitro. Studies in vivo established that tea also induces cytochromes P450 and Phase II enzymes in a manner consistent with the rapid metabolism and excretion of heterocyclic amines. Collectively, the results indicate that tea possesses anticarcinogenic activity in the colon, and this most likely involves multiple inhibitory mechanisms.  (+info)

(8/1351) Involvement of endothelium/nitric oxide in vasorelaxation induced by purified green tea (-)epicatechin.

The present study investigated the involvement of endothelial nitric oxide in relaxation induced by purified green tea (-)epicatechin in rat isolated mesenteric arteries. (-)Epicatechin caused both endothelium-dependent and -independent relaxation. NG-Nitro-L-arginine methyl ester (L-NAME, 100 microM) and methylene blue (10 microM) significantly attenuated (-)epicatechin-induced relaxation in endothelium-intact tissues. L-Arginine (1 mM) partially antagonized the effect of L-NAME. (-)Epicatechin-induced relaxation was inhibited by Rp-guanosine 3',5'-cyclic monophosphothioate triethylamine. In contrast, indomethacin and glibenclamide had no effect. (-)Epicatechin (100 microM) significantly increased the tissue content of cyclic GMP and NG-nitro-L-arginine (100 microM) or removal of the endothelium abolished this increase. (-)Epicatechin (100 microM) induced an increase in intracellular Ca2+ levels in cultured human umbilical vein endothelial cells. Iberiotoxin at 100 nM attenuated (-)epicatechin-induced relaxation in endothelium-intact arteries and this effect was absent in the presence of 100 microM L-NAME. In summary, (-)epicatechin-induced endothelium-dependent relaxation is primarily mediated by nitric oxide and partially through nitric oxide-dependent activation of iberiotoxin-sensitive K+ channels. In addition, there may be a causal link between increased Ca2+ levels and nitric oxide release in response to (-)epicatechin.  (+info)