Green tea extracts

Green tea extracts show anti-radiation property on white rats in radioactive isotope experiments.

In addition, green tea extracts also contain a wide-ranged anti-inflammation characteristic, so it may be helpful in treating chronic inflammatory states. The bactericidal activity against S.mutans is conspicuous in Japanese green tea extracts, and the maltose level in mouth is consistently lower after drinking tea. Therefore, green tea extracts may be effective in oral hygiene maintenance.

Moreover, the anti-cancer property make the green tea extracts a hotspot in recent scientific researches. In many experiments, green tea extracts show inhibitory effects on cancer cells. In vitro assays, Catechin and caffeine, which are main components in green tea extracts, block the cell cycle of cancer cells (cytotoxicity) and induce programmed cell death; in vivo, green tea extracts also inhibits prostatic carcinoma transplanted in nude mice.

Green tea extracts exhibit stronger antioxidant protection for human body than vitamin C and vitamin E. Scavenging effect of lipid free-radicals (one antioxidant property) of polyphenols in green tea extracts can be clearly observed in experiments. The ability of GTP in green tea extracts to eliminate lipid-derived free radicals is noticeably stronger (almost 50 times) than that of ginkgo biloba extracts. Further investigations indicate that the boosting level of superoxide dismutase (SOD) and glutathione dismutase (GSHPx) may account for the inhibitory effect of GTC against lipid oxidation. It should be mentioned that from the antioxidant perspective, green tea extracts are, generally speaking, more effective than black tea extracts due to the better preservation of catechins.

The biochemical properties of green tea extracts can be generally divided into four aspects antioxidant, anti-cancer, anti-inflammation, and anti-radiation.

In a high temperature environment, GTC is not stable: an epimerization change is likely to occur, because heating results in the conversion from EGCG to GCG. Thus it is considered inappropriate to infuse green tea or its extracts with overheated water.

In alkaline solutions (pH > 8) GTC (green tea catechins) is rather unstable; in acidic solutions (pH < 4), however, GTC shows excellent stability. The stability in alkaline solutions varies between four components of GTC in green tea extracts. Recent study demonstrates that EGCG and EGC is more unstable than EC and ECG in a basic solution, giving an explanation to the fact that EGCG and EGC does not circulated in the basic sodium phosphate buffer fluid of human body

Green tea extract is 20 times more antioxidant-active than Vitamin C. The main attribution is supposed to be EGCG

Green tea extract