Epigallocatechin gallate

"EGCG" redirects here. For the software, see Extended GCG.
Epigallocatechin gallate
Structural formula of epigallocatechin gallate
Space-filling model of the epigallocatechin gallate molecule
Names
IUPAC name
[(2R,3R)-5,7-dihydroxy-2-(3,4,5-trihydroxyphenyl)chroman-3-yl] 3,4,5-trihydroxybenzoate
Preferred 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 gallate
Identifiers
989-51-5 N
ChEBI CHEBI:4806 YesY
ChEMBL ChEMBL297453 YesY
ChemSpider 58575 YesY
7002
Jmol interactive 3D Image
MeSH Epigallocatechin+gallate
PubChem 65064
Properties
C22H18O11
Molar mass 458.372 g/mol
Appearance
soluble (33.3-100 g/L)[1]
Solubility soluble in ethanol, DMSO, dimethyl formamide[1] at about 20 g/l[2]
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Infobox references

Epigallocatechin gallate (EGCG), also known as epigallocatechin-3-gallate, is the ester of epigallocatechin and gallic acid, and is a type of catechin.

EGCG, the most abundant catechin in tea, is a polyphenol under basic research for its potential to affect human health and disease. EGCG is used in many dietary supplements.

Food sources

Tea

It is found in high content in the dried leaves of white tea (4245 mg per 100 g), green tea (7380 mg per 100 g) and, in smaller quantities, black tea.[3] During black tea production, the catechins are mostly converted to theaflavins and thearubigins.[4] via polyphenol oxidases.

Other

Trace amounts are found in apple skin, plums, onions, hazelnuts, pecans and carob powder (at 109 mg per 100 g).[3]

Bioavailability

When taken orally, EGCG has poor bioavailability even at such a high amount of daily intake equivalent to 8-16 cups of tea (800 mg), a dose causing mild adverse effects, such as nausea or heartburn.[5] After consumption, EGCG blood levels peak within 1.7 hours, then are excreted into the urine over 3-15 hours.[6]

Research on potential therapeutic uses

EGCG has been the subject of a number of basic and clinical research studies investigating its potential use as a therapeutic for a broad range of disorders.[7][8][9] As of 2015, however, these effects remain unsubstantiated in humans and there are no approved health claims for EGCG in the United States or Europe.[8][9] The US Food and Drug Administration has issued warning letters against marketers of products claiming that EGCG provides anti-disease effects or overall health benefits.[10][11]

See also

References

  1. 1 2 http://chemicalland21.com/lifescience/foco/%28-%29-EPIGALLOCATECHIN%20GALLATE.htm
  2. ↑ http://www.caymanchem.com/pdfs/70935.pdf
  3. 1 2 "USDA Database for the Flavonoid Content of Selected Foods, Release 3" (PDF). US Department of Agriculture. 2011. Retrieved 18 May 2015.
  4. ↑ Lorenz M, Urban J (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.
  5. ↑ Chow HH, Cai Y, Hakim IA, Crowell JA, Shahi F, Brooks CA, Dorr RT, Hara Y, Alberts DS (2003). "Pharmacokinetics and safety of green tea polyphenols after multiple-dose administration of epigallocatechin gallate and polyphenon E in healthy individuals". Clin Cancer Res 9 (9): 3312–9. PMID 12960117.
  6. ↑ Lee MJ, Maliakal P, Chen L, Meng X, Bondoc FY, Prabhu S, Lambert G, Mohr S, Yang CS (2002). "Pharmacokinetics of tea catechins after ingestion of green tea and (-)-epigallocatechin-3-gallate by humans: formation of different metabolites and individual variability". Cancer Epidemiol Biomarkers Prev 11 (10 Pt 1): 1025–32. PMID 12376503.
  7. ↑ Fürst, R; Zündorf, I (2014). "Plant-derived anti-inflammatory compounds: hopes and disappointments regarding the translation of preclinical knowledge into clinical progress". Mediators Inflamm 2014: 146832. doi:10.1155/2014/146832. PMID 24987194.
  8. 1 2 "Green tea". MedlinePLus, US National Library of Medicine. 9 June 2015. Retrieved 15 September 2015.
  9. 1 2 "Scientific Opinion on the substantiation of health claims related to Camellia sinensis (L.) Kuntze (tea), including catechins in green tea, and improvement of endothelium-dependent vasodilation (ID 1106, 1310), maintenance of normal blood pressure (ID 1310, 2657), maintenance of normal blood glucose concentrations (ID 1108), maintenance of normal blood LDL cholesterol concentrations (ID 2640), protection of the skin from UV-induced (including photo-oxidative) damage (ID 1110, 1119), protection of DNA from oxidative damage (ID 1120, 1121), protection of lipids from oxidative damage (ID 1275), contribution to normal cognitive function (ID 1117, 2812), “cardiovascular system” (ID 2814), “invigoration of the body” (ID 1274, 3280), decreasing potentially pathogenic gastro-intestinal microorganisms (ID 1118), “immune health” (ID 1273) and “mouth” (ID 2813) pursuant to Article 13(1) of Regulation (EC) No 1924/2006". EFSA Journal (European Food Safety Authority) 9 (4). 2011. doi:10.2903/j.efsa.2011.2055.
  10. ↑ "Inspections, Compliance, Enforcement, and Criminal Investigations: Warning Letter to Sharp Labs Inc". Food and Drug Administration. 9 July 2008. Retrieved 15 September 2015.
  11. ↑ "Inspections, Compliance, Enforcement, and Criminal Investigations: Warning Letter to Fleminger Inc". Food and Drug Administration. 22 February 2010. Retrieved 6 January 2015.
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