Polyphenols from green tea

Challa, A., Katiyar, S.K., Cooper, K.D., and Mukhtar, H., Inhibition of UV-radiation-caused induction of oxidative stress and immunosuppression in C3H/HeN mice by polyphenols from green tea, J. Investigative Dermatol, accepted, 1998. 

HAQQI T M, ANTHONY D D, GUPTA S, AHMAD N, LEE M S, KUMAR G K and MUKHTAR H (1999) Prevention of coUagen-induced arthritis in mice by a polyphenolic fraction from green tea , Proc Natl Acad Sci USA, 96 (8), 4524-9. 

KATIYAR s K, MATSUI M s, ELMETS c A and MUKHTAR H (1999) Polyphenolic antioxidant epigallocatechin gallate from green tea reduces UVB-induced inflammatory responses and infiltration of leukocytes in human skin , Photochem Photobiol, 69, 148-53. 

PhIP. The inhibition by tea of these two tests, which are indicators of genotoxicity, suggests that naturally occurring plant extracts can modify metabolic activation of HAAs. Tea polyphenols, epigallocatechin gallate from green tea and theaflavin gal-late from black tea, display similar inhibiting action in both tests (see ref. 318). 

This added one more bit of data to the argument that the benefits of red wine come from the type of antioxidants termed polyphenols and flavonoids. Those chemical substances never get into white wine, since grape skins are removed at the start of the fermentation process. But one can very easily get those polyphenols and flavonoids from red grape juice or pomegranate juice. Or, for that matter, from green tea and a wide variety of fruits and vegetables. Or from beer. 

Zhang, L., Chow, M. S. S., and Zuo, Z. 2006. Effect of the co-occurring components from green tea on the intestinal absorption and disposition of green tea polyphenols in Caco-2 monolayer model. J. Pharm. Pharmacol. 58 37-44. 

The majority of the biological functions of teas may be attributed to their poly-phenolic components (see figures 9.1 and 9.2) the chemical structures of the main polyphenols isolated from green, black, oolong, and pu-erh teas are structurally related but not identical. The monomeric catechins from green tea may be considered the precursors of the more complex polyphenols found in other teas as a result of fermentation. 

Haqqi,TM.,Anthony, D.D., Gupta, S.,Ahmad,N., Lee, M.S., Kumar, G.K., and Mukhtar, H. (1999) Prevention of CoUagen-Induced Arthritis in Mice by a Polyphenolic Fraction from Green Tea, Proc. Nat. Acad. Sci. USA 96,4524-A529. 

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