Antioxidant capacity of different types of tea products Karori, S. M.1, Wachira, F. N. 1*, Wanyoko, J. K.2 and Ngure, R. M.1 1
Department of Biochemistry and Molecular Biology, Egerton University, P.O Box 536, Njoro, Kenya. Department of Chemistry, Tea Research Foundation of Kenya (TRFK), P.O Box 820 Kericho, Kenya.
2
Accepted 14 June, 2007
In the present study, twelve different types of commercial tea samples were assayed to determine their phenolic composition and antioxidant activity. Reverse phase high performance liquid chromatography using a binary gradient system was used for the identification and quantification of individual catechins. Subsequently, total phenolic content was determined spectrophotometrically according to the Folin-ciocalteus method. Total theaflavins and thearubigins were also determined. The radical scavenging behavior of the polyphenols on 2,2-diphenyl-1-picrylhydrazyl radical (DPPH) was also studied spectrophotometrically. The results showed that total polyphenols, total catechins and antioxidant activity were significantly (P
