Studies on the molecular mechanisms of anti-oxidation and anti- inflammation by tea and phyto-polyphenolic compounds

• Main Authors: Lin, Yu-Li, 林郁里
• Other Authors: Lin Jen-Kun
• Format: Others
• Language: zh-TW
• Published: 1997
• Online Access: http://ndltd.ncl.edu.tw/handle/32921712742067125689

博士 === 國立臺灣大學 === 生化學研究所 === 85 === The polyphenols in ten eifferent types of commercial tea (manufactured tea) were analyzed by HPLC. Ten different types of commercial tea, includiogunfermented, semifermented and fermented tea, were analyzed for theirpolyphenol compounds, and it was foynd that both yields of solids in teawater extracts (TWEs), and the amount of EGCG in these products, variedwith different tea leaves and processiog methods. Longjing tea (unfermentedgreen tea) contained the highest concentration of EGCG and polyphenols,whereas Assam black tea (most fermented) contained the least. We also foundthat green tea polyphenols (GTPs) and EGCG strongly inhibited peroxyl- radical generation. The evidence suggests that the strong antioxidativeactivity of Longjing TWEs and GTPs are mainly due to the higher contents oftea polyphenols. In the animal study, Wistar rats were fed 2.5% green tea leaves (Longjingtea). At the 27 and 63 weeks, the change of AST, ALT, r-GT, and creatinine were not significant in treated group as compared with control group. Thesesuggested that eating of green tea leaves were not damage to the liver and kidney. Serum triglyceride, total-cholesterol, and LDL-C were decreased.Interesting, the dieatry intake of the two group were similary, but the bodyweight of green tea leaves group were decreased 10%~18% than the controlgroup. Additionally, the superoxide dismutase (SOD) activity in the serumwas increased in treated group. The activities of antioxidant enzyme (SODand catalase) and phase 2 enzyme (GST) and glutathione concentration in theliver of Wistar rats were higher in treated group than in control group. Thesignificance of these resylts can be implicated in relation to the cancerchemopreventive effects of green tea against the induction of tumors.