Catechin (polyphenol) in tea
Epigallocatechin gallate Names IUPAC name (2R ,3R )-3′,4′,5,5′,7-Pentahydroxyflavan-3-yl 3,4,5-trihydroxybenzoate
Systematic IUPAC name (2R ,3R )-5,7-Dihydroxy-2-(3,4,5-trihydroxyphenyl)-3,4-dihydro-2H -1-benzopyran-3-yl 3,4,5-trihydroxybenzoate
Other names(-)-Epigallocatechin gallateR ,3R )-3′,4′,5,5′,7-pentahydroxyflavan-3-yl gallate
Identifiers ChEBI ChEMBL ChemSpider ECHA InfoCard 100.111.017 KEGG MeSH Epigallocatechin+gallate UNII InChI=1S/C22H18O11/c23-10-5-12(24)11-7-18(33-22(31)9-3-15(27)20(30)16(28)4-9)21(32-17(11)6-10)8-1-13(25)19(29)14(26)2-8/h1-6,18,21,23-30H,7H2/t18-,21-/m1/s1
Y Key: WMBWREPUVVBILR-WIYYLYMNSA-N
Y InChI=1/C22H18O11/c23-10-5-12(24)11-7-18(33-22(31)9-3-15(27)20(30)16(28)4-9)21(32-17(11)6-10)8-1-13(25)19(29)14(26)2-8/h1-6,18,21,23-30H,7H2/t18-,21-/m1/s1
Key: WMBWREPUVVBILR-WIYYLYMNBM
Properties C 22 H 18 O 11 Molar mass 458.372 g/mol soluble (5 g/L)[vague [ 1] Solubility soluble in ethanol, DMSO, dimethyl formamide[ 1] Except where otherwise noted, data are given for materials in their
standard state (at 25 °C [77 °F], 100 kPa).
Chemical compound
Epigallocatechin gallate (EGCG ), also known asepigallocatechin-3-gallate , is theester ofepigallocatechin andgallic acid , and is a type ofcatechin .
EGCG – the most abundant catechin intea – is apolyphenol underbasic research for its potential to affect human health and disease. EGCG is used in manydietary supplements .
It is found in high content in the dried leaves ofgreen tea (7380 mg per 100 g),white tea (4245 mg per 100 g), and in smaller quantities,black tea (936 mg per 100 g).[ 2] theaflavins andthearubigins viapolyphenol oxidases .[which? [ 3]
Trace amounts are found inapple skin,plums ,onions ,hazelnuts ,pecans , andcarob powder (at 109 mg per 100 g).[ 2]
When taken orally, EGCG has poor absorption even at daily intake equivalent to 8 to 16 cups of green tea, an amount causingadverse effects such asnausea orheartburn .[ 4] [ 5] plasma half-life is around 5 hours,[ 5] urine over 0 to 8 hours.[ 5] [ 6]
Well-studied inbasic research , EGCG has variousbiological effects in laboratory studies.[ 7] [ 8] [ 9] [ 10]
A 2011 analysis by theEuropean Food Safety Authority found that acause and effect relationship could not be shown for a link between tea catechins and the maintenance of normal blood LDL-cholesterol concentration.[ 11] LDL cholesterol .[ 12]
A 2018 review showed that excessive intake of EGCG may causeliver toxicity .[ 13] European Food Safety Authority stated that daily intake of 800 mg or more could increase risk of liver damage.[ 14]
Taken as a capsule or tablet 338 mg per day of EGCG is considered safe, whereas 704 mg per day is safe if consumed as a tea beverage.[ 13] mL of green tea contains about 70.2 mg of EGCG (about 165 mg per cup).[ 14]
Over 2008 to 2017, the USFood and Drug Administration issued severalwarning letters to manufacturers of dietary supplements containing EGCG for violations of theFederal Food, Drug, and Cosmetic Act . Most of these letters informed the companies that their promotional materials promoted EGCG-based dietary supplements in the treatment or prevention of diseases or conditions that cause them to be classified as drugs under theUnited States code ,[ 15] [ 16] [ 17] [ 18] new drugs ", without approval as required under the Act.[ 17]
^a b "(−)-Epigallocatechin gallate" .Chemicalland21.com .^a b Bhagwat, Seema; Haytowitz, David B.; Holden, Joanne M. (September 2011).USDA Database for the Flavonoid Content of Selected Foods, Release 3 (PDF) (Report). Agricultural Research Service, U.S. Department of Agriculture. pp. 2,98– 103. Retrieved18 May 2015 . ^ Lorenz, Mario; Urban, Janka; Engelhardt, Ulrich; Baumann, Gert; Stangl, Karl; Stangl, Verena (January 2009). "Green and Black Tea are Equally Potent Stimuli of NO Production and Vasodilation: New Insights into Tea Ingredients Involved".Basic Research in Cardiology .104 (1):100– 110.doi :10.1007/s00395-008-0759-3 .PMID 19101751 .S2CID 20844066 . ^ Chow, H.-H. Sherry; Cai, Yan; Hakim, Iman A.; Crowell, James A.; Shahi, Farah; Brooks, Chris A.; Dorr, Robert T.; Hara, Yukihiko; Alberts, David S. (15 August 2003)."Pharmacokinetics and safety of green tea polyphenols after multiple-dose administration of epigallocatechin gallate and polyphenon E in healthy individuals" .Clinical Cancer Research .9 (9):3312– 3319.PMID 12960117 . ^a b c Lee, Mao-Jung; Maliakal, Pius; Chen, Laishun; Meng, Xiaofeng; Bondoc, Flordeliza Y.; Prabhu, Saileta; Lambert, George; Mohr, Sandra; Yang, Chung S. (October 2002)."Pharmacokinetics of tea catechins after ingestion of green tea and (−)-epigallocatechin 3-gallate by humans: formation of different metabolites and individual variability" .Cancer Epidemiology, Biomarkers & Prevention .11 (10 Pt 1):1025– 1032.PMID 12376503 . ^ Manach, C; Williamson, G; Morand, C; Scalbert, A; Rémésy, C (January 2005)."Bioavailability and bioefficacy of polyphenols in humans. I. Review of 97 bioavailability studies" .The American Journal of Clinical Nutrition .81 (1 Suppl):230S – 242S .doi :10.1093/ajcn/81.1.230S PMID 15640486 . ^ Fürst, Robert; Zündorf, Ilse (May 2014)."Plant-derived anti-inflammatory compounds: hopes and disappointments regarding the translation of preclinical knowledge into clinical progress" .Mediators of Inflammation .2014 146832.doi :10.1155/2014/146832 PMC 4060065 PMID 24987194 . 146832. ^ Granja, Andreia; Frias, Iúri; Neves, Ana Rute; Pinheiro, Marina; Reis, Salette (2017)."Therapeutic Potential of Epigallocatechin Gallate Nanodelivery Systems" .BioMed Research International .2017 :1– 15.doi :10.1155/2017/5813793 ISSN 2314-6133 .PMC 5534279 PMID 28791306 . ^ Wu, Dayong; Wang, Junpeng; Pae, Munkyong; Meydani, Simin Nikbin (2012). "Green tea EGCG, T cells, and T cell-mediated autoimmune diseases".Molecular Aspects of Medicine .33 (1):107– 118.doi :10.1016/j.mam.2011.10.001 .ISSN 0098-2997 .PMID 22020144 . ^ Riegsecker, Sharayah; Wiczynski, Dustin; Kaplan, Mariana J.; Ahmed, Salahuddin (2013)."Potential benefits of green tea polyphenol EGCG in the prevention and treatment of vascular inflammation in rheumatoid arthritis" .Life Sciences .93 (8):307– 312.doi :10.1016/j.lfs.2013.07.006 .PMC 3768132 PMID 23871988 . ^ EFSA NDA Panel (EFSA Panel on Dietetic Products, Nutrition and Allergies) (2011)."Scientific Opinion on the substantiation of health claims related toCamellia sinensis (L.) Kuntze (tea), including catechins in green tea, and improvement of endothelium-dependent vasodilation (ID 1106, 1310), maintenance of normal blood pressure" .EFSA Journal .9 (4): 2055.doi :10.2903/j.efsa.2011.2055 ^ Momose Y; et al. (2016). "Systematic review of green tea epigallocatechin gallate in reducing low-density lipoprotein cholesterol levels of humans".International Journal of Food Sciences and Nutrition .67 (6):606– 613.doi :10.1080/09637486.2016.1196655 .PMID 27324590 .S2CID 39704366 . ^a b Hu, J; Webster, D; Cao, J; Shao, A (2018)."The safety of green tea and green tea extracts consumption in adults – Results of a systematic review" .Regulatory Toxicology and Pharmacology .95 :412– 433.doi :10.1016/j.yrtph.2018.03.019 PMID 29580974 . ^a b Younes, Maged; Aggett, Peter; Aguilar, Fernando; et al. (18 April 2018)."Scientific opinion on the safety of green tea catechins" .EFSA Journal .16 (4): e05239.doi :10.2903/j.efsa.2018.5239 PMC 7009618 PMID 32625874 . ^ "Sharp Labs Inc: Warning Letter" .Inspections, Compliance, Enforcement, and Criminal Investigations . Food and Drug Administration. 9 July 2008. Archived fromthe original on 23 October 2016. Retrieved15 September 2015 .^ "Fleminger Inc.: Warning Letter" .Inspections, Compliance, Enforcement, and Criminal Investigations . Food and Drug Administration. 22 February 2010. Archived fromthe original on 23 October 2016. Retrieved6 January 2015 .^a b "LifeVantage Corporation: Warning Letter" .Inspections, Compliance, Enforcement, and Criminal Investigations . Food and Drug Administration. 17 April 2017. Archived fromthe original on April 26, 2017. Retrieved30 September 2017 .^ "N.V.E. Pharmaceuticals, Inc.: Warning Letter" .Inspections, Compliance, Enforcement, and Criminal Investigations . Food and Drug Administration. 22 July 2013. Archived fromthe original on March 10, 2014. Retrieved30 September 2017 .
Food antioxidants Fuel antioxidants Measurements
Flavan-3-ols O-methylated flavan-3ols Glycosides Acetylated Gallate esters Misc.
ER Tooltip Estrogen receptor
Agonists Steroidal: 2-Hydroxyestradiol 2-Hydroxyestrone 3-Methyl-19-methyleneandrosta-3,5-dien-17β-ol 3α-Androstanediol 3α,5α-Dihydrolevonorgestrel 3β,5α-Dihydrolevonorgestrel 3α-Hydroxytibolone 3β-Hydroxytibolone 3β-Androstanediol 4-Androstenediol 4-Androstenedione 4-Fluoroestradiol 4-Hydroxyestradiol 4-Hydroxyestrone 4-Methoxyestradiol 4-Methoxyestrone 5-Androstenediol 7-Oxo-DHEA 7α-Hydroxy-DHEA 7α-Methylestradiol 7β-Hydroxyepiandrosterone 8,9-Dehydroestradiol 8,9-Dehydroestrone 8β-VE2 10β,17β-Dihydroxyestra-1,4-dien-3-one (DHED) 11β-Chloromethylestradiol 11β-Methoxyestradiol 15α-Hydroxyestradiol 16-Ketoestradiol 16-Ketoestrone 16α-Fluoroestradiol 16α-Hydroxy-DHEA 16α-Hydroxyestrone 16α-Iodoestradiol 16α-LE2 16β-Hydroxyestrone 16β,17α-Epiestriol (16β-hydroxy-17α-estradiol) 17α-Estradiol (alfatradiol )17α-Dihydroequilenin 17α-Dihydroequilin 17α-Epiestriol (16α-hydroxy-17α-estradiol) 17α-Ethynyl-3α-androstanediol 17α-Ethynyl-3β-androstanediol 17β-Dihydroequilenin 17β-Dihydroequilin 17β-Methyl-17α-dihydroequilenin Abiraterone Abiraterone acetate Alestramustine Almestrone Anabolic steroids (e.g.,testosterone andesters ,methyltestosterone ,metandienone (methandrostenolone) ,nandrolone andesters , many others; via estrogenic metabolites)Atrimustine Bolandiol Bolandiol dipropionate Butolame Clomestrone Cloxestradiol Conjugated estriol Conjugated estrogens Cyclodiol Cyclotriol DHEA DHEA-S ent -EstradiolEpiestriol (16β-epiestriol, 16β-hydroxy-17β-estradiol) Epimestrol Equilenin Equilin ERA-63 (ORG-37663) Esterified estrogens Estetrol Estradiol Estramustine Estramustine phosphate Estrapronicate Estrazinol Estriol Estrofurate Estrogenic substances Estromustine Estrone Etamestrol (eptamestrol) Ethinylandrostenediol Ethinylestradiol Ethinylestriol Ethylestradiol Etynodiol Etynodiol diacetate Hexolame Hippulin Hydroxyestrone diacetate Lynestrenol Lynestrenol phenylpropionate Mestranol Methylestradiol Moxestrol Mytatrienediol Nilestriol Norethisterone Noretynodrel Orestrate Pentolame Prodiame Prolame Promestriene RU-16117 Quinestradol Quinestrol Tibolone Xenoestrogens: Anise -related (e.g.,anethole ,anol ,dianethole ,dianol ,photoanethole )Chalconoids (e.g.,isoliquiritigenin ,phloretin ,phlorizin (phloridzin) ,wedelolactone )Coumestans (e.g.,coumestrol ,psoralidin )Flavonoids (incl.7,8-DHF ,8-prenylnaringenin ,apigenin ,baicalein ,baicalin ,biochanin A ,calycosin ,catechin ,daidzein ,daidzin ,ECG ,EGCG ,epicatechin ,equol ,formononetin ,glabrene ,glabridin ,genistein ,genistin ,glycitein ,kaempferol ,liquiritigenin ,mirificin ,myricetin ,naringenin ,penduletin ,pinocembrin ,prunetin ,puerarin ,quercetin ,tectoridin ,tectorigenin )Lavender oil Lignans (e.g.,enterodiol ,enterolactone ,nyasol (cis -hinokiresinol) )Metalloestrogens (e.g.,cadmium )Pesticides (e.g.,alternariol ,dieldrin ,endosulfan ,fenarimol ,HPTE ,methiocarb ,methoxychlor ,triclocarban ,triclosan )Phytosteroids (e.g.,digitoxin (digitalis ),diosgenin ,guggulsterone )Phytosterols (e.g.,β-sitosterol ,campesterol ,stigmasterol )Resorcylic acid lactones (e.g.,zearalanone ,α-zearalenol ,β-zearalenol ,zearalenone ,zeranol (α-zearalanol) ,taleranol (teranol, β-zearalanol) )Steroid -like (e.g.,deoxymiroestrol ,miroestrol )Stilbenoids (e.g.,resveratrol ,rhaponticin )Synthetic xenoestrogens (e.g.,alkylphenols ,bisphenols (e.g.,BPA ,BPF ,BPS ),DDT ,parabens ,PBBs ,PHBA ,phthalates ,PCBs )Others (e.g.,agnuside ,rotundifuran ) MixedSERMs Tooltip Selective estrogen receptor modulators ) Antagonists Coregulator-binding modulators: ERX-11
GPER Tooltip G protein-coupled estrogen receptor
Agonists Antagonists Unknown
Transporter
EAATs Tooltip Excitatory amino acid transporters vGluTs Tooltip Vesicular glutamate transporters
Enzyme
GAH Tooltip Glutamine aminohydrolase (glutaminase) AST Tooltip Aspartate aminotransferase ALT Tooltip Alanine aminotransferase GDH Tooltip Glutamate dehydrogenase GS Tooltip Glutamine synthetase GAD Tooltip Glutamate decarboxylase
Common
General Culture
History Production and
Preparation Health Tea-based See also
