Chemical structure Epigallocatechin gallate(EGCG), also known as epigallocatechin 3-gallate, is the ester of epigallocatechin and gallic acid, and is a type of catechin.
Molecular formula C22H18O11
Molar mass 458.37 g mol-1
EGCG is the most abundant catechin in tea and is a potent antioxidant that may have therapeutic applications in the treatment of many disorders (e.g. cancer). It is found in green - but not black - tea, as EGCG is converted into thearubigins in black teas. In a high temperature environment, an epimerization change is more likely to occur; however as exposure to boiling water for 30 straight minutes only leads to a 12.4% reduction in the total amount of EGCG, the amount lost in a brief exposure is insignificant. In fact, even when special conditions were used to create temperatures well over that of boiling water, the amount lost scaled up only slightly.EGCG can be found in many supplements.EGCG and HIV
has been research investigating the benefit
of EGCG from green tea in the treatment
of HIV infection, where EGCG has been
shown to reduce plaques related to AIDS-related
dementia in the laboratory, as well as
block gp120. However, these
effects have yet to be confirmed in live
human trials, and it does not imply that
green tea will cure or block HIV infection,
but it may help regulate viral load as
long as it is not involved in adverse
drug reactions. The concentrations of
EGCG used in the studies could not be
reached by drinking green tea. More study
into EGCG and HIV is currently underway. There
is increasing evidence to show that EGCG
along with other flavonoids can be beneficial
in treating brain, prostate, cancers. EGCG has been shown to bind and
inhibit the anti-apoptotic protein Bcl-xl, which has been implicated
in both cancer cell and normal cell survival.
EGCG and endometriosis
Xu et al. found that antiangiogenic effects of EGCG inhibits the growth of blood vessels and thus reduces lesion size in experimental endometriosis (mouse model).>Drug Interactions.
A recent study using mouse models at the University of Southern California showed that, in contrast to the myriad benefits commonly associated with green tea and green tea extract (GTE), EGCG binds with the anti-cancer drug Velcade, significantly reducing its bioavailability and thereby rendering it therapeutically useless. Dr. SchÃ¶nthal, who headed the study, suggests that consumption of green tea and GTE products be strongly contraindicated for patients undergoing treatment for multiple myeloma and mantle cell lymphoma. EGCG has a slight stimulatory effect due to it increasing adrenaline levels. Epigallocatechin-3-gallate, may reduce the bioavaialbilty of the drug sunitinib when they are taken together.EGCG was, among other tea polyphenols, found to be a strong topoisomerase inhibitor, similar to some chemotherapeutic anticancer drugs, for example, etoposide and doxorubicin. This property may be responsible for anticarcinogenic however also a carcinogenic potential of the substance. High intake of polyphenolic compounds during pregnancy is suspected to increase risk of neonatal leukemia. Bioflavonoid supplements should not be used by pregnant women.A strong association between high intake of tea during pregnancy and elevated risk of childhood malignant central nervous system (CNS) tumours was found.