Theaflavin digallate
Encyclopedia
Theaflavin digallate is an antioxidant polyphenol found in black tea
, and a theaflavin
derivative.
Black tea
Black tea is a variety of tea that is more oxidized than the oolong, green, and white varieties.All four varieties are made from leaves of the shrub Camellia sinensis. Black tea is generally stronger in flavor and contains more caffeine than the less oxidized teas. Two principal varieties of the...
, and a theaflavin
Theaflavin
Theaflavin and its derivatives, known collectively as theaflavins, are antioxidant polyphenols that are formed from flavan-3-ols such as in tea leaves during the enzymatic oxidation of tea leaves, such as in black tea. Theaflavins are types of thearubigins, and are therefore reddish in color...
derivative.
Health
- TF-3 is a potent scavenger of superoxideSuperoxideA superoxide, also known by the obsolete name hyperoxide, is a compound that possesses the superoxide anion with the chemical formula O2−. The systematic name of the anion is dioxide. It is important as the product of the one-electron reduction of dioxygen O2, which occurs widely in nature...
, even more so than EGCGEpigallocatechin gallateEpigallocatechin gallate , also known as epigallocatechin 3-gallate, is the ester of epigallocatechin and gallic acid, and is a type of catechin....
. - Tea polyphenols including theaflavin TFDG are found to reduce angiogenesisAngiogenesisAngiogenesis is the physiological process involving the growth of new blood vessels from pre-existing vessels. Though there has been some debate over terminology, vasculogenesis is the term used for spontaneous blood-vessel formation, and intussusception is the term for the formation of new blood...
, which is implicated in non-liquid cancers, an area of intense current research, by decreasing vascular endothelial growth factorVascular endothelial growth factorVascular endothelial growth factor is a signal protein produced by cells that stimulates vasculogenesis and angiogenesis. It is part of the system that restores the oxygen supply to tissues when blood circulation is inadequate....
production and receptor phosphorylation. - Epigallocatechin gallateEpigallocatechin gallateEpigallocatechin gallate , also known as epigallocatechin 3-gallate, is the ester of epigallocatechin and gallic acid, and is a type of catechin....
(EGCG), a catechin in green tea, binds to gp120Gp120Envelope glycoprotein GP120 is a glycoprotein exposed on the surface of the HIV envelope. The 120 in its name comes from its molecular weight of 120 kilodaltons...
, which works in conjunction with gp41Gp41gp41 is a subunit of the envelope protein complex of retroviruses, including Human immunodeficiency virus and Simian-Human immunodeficiency virus. This glycoprotein subunit remains non-covalently-bound to gp120, and provides the second step by which HIV enters the cell...
, itself blocked by TF-3, both receptors of which HIV hijacks to enter into healthy human immune cells. Therefore, former and latter compounds have considerable potential to block HIV entry, though in real life situations other factors may complicate matters. More studies need to be done. as well as inhibit 3CLPro of severe acute respiratory syndromeSevere acute respiratory syndromeSevere Acute Respiratory Syndrome is a respiratory disease in humans which is caused by the SARS coronavirus . Between November 2002 and July 2003 an outbreak of SARS in Hong Kong nearly became a pandemic, with 8,422 cases and 916 deaths worldwide according to the WHO...
(SARS).