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Abstract
Tea contains several phenolic / polyphenolic components which are antioxidant in nature, and many studies have shown that tea possesses the ability to prevent oxidant-induced cellular damage.The antioxidant activity of green tea has recently been reported however, information on the relationship between antioxidant activity and phenolic content and composition of green tea is still not sufficient. Therefore, the present study aims to: Determine the contents of total phenolics in green tea. Study the effect of different preparing methods on the phenolic compounds content of green tea. The effect of using phenolic extracts chemoprevention of cancer will be in the scope of this study. The obtained data could be summarized as follow: A noticeable decreasing was observed in antioxidant activity with the elongation of boiling time treatment. While a slightly decreasing was observed with the elongation of soaking in cold water time treatment. After 48 h of soaking in cold water treatment antioxidant activity was decreased by 7 . A remarkable decrease was observed with the elongation of soaking in boiled water . After 10 min of soaking in boiled water.Electrophortic pattern of nucleic acids, (DNA, RNA) in human leukocytes treated with Benzo(a)Pyrene and green tea. indicated that benzo(a)Pyrene induced DNA damage Pre-treatment, simultaneous, and post-treatment reduced the DNA damage . The leukocytes treated with Green tea the peak intensity of DNA fragmentation was decreased with value of 7 when compared with control. Pre- treatment with Green tea (boiled 2 min ) decreased the mean of peak intensity where as the treatment with B(a)P only increased the mean of peak intensity of fragmentation DNA. Effect of green tea on the genotoxicity induced by benzo(a)pyrere [B(a)P], [B(a)P]-DNA adduct formation using thin layer chromatography (TLC). Showed that a high intenity band was appear treatment of B(a)P while the intensity of the band that reflect the adduction of B(a)P with nucleic acids was reduced in simultaneous treatment then in post- and pre-treatments, respectively.