Abstract: The antioxidant activity of tea polyphenols (TP) and the cooperative antioxidant activity of TP and other natural antioxidants were determined by using ferric reducing /antioxidant power assay(FRAP) established by Benzie and Strain. The results showed that it showed the highest antioxidant activity when the concentration of EGCG in tea catechins was 40%~50%. The cooperative antioxidant activity of antioxidants was related to the antioxidant activity of antioxidants themselves and the effective concentration of antioxidants. A weak activity was showed when the effective concentration of antioxidants was low, and as the concentration increased, the cooperative activity was increasing until the maximum synergizing effect, and then, the synergizing effect on antioxidant activity declined.

Key words: FRAP, tea polyphenol (TP), synergy of antioxidant