Synergistic antioxidant activity among polyphenols by response surface methodology

DPPH free radical clearance was used as the evaluation index of antioxidant activity. Because tea polyphenols, catechins, chlorogenic acid and gallic acid had stronger antioxidant, they were selected as influencing factors. The synergistic antioxidant activity of the mixture of polyphenols was analyzed by the response surface methodology.Tea polyphenols, catechins, chlorogenic acid, gallic acid had significant effect on the capacity of scavenging DPPH free radicals.The capacity of scavenging DPPH free radicals was as follows: gallic acid, catechin, tea polyphenols, chlorogenic acid. There were interactions between polyphenols, but the interaction was not significant for the capacity of scavenging DPPH free radicals ( except gallic acid and tea polyphenols) . Except the first experiment and the thirteen experiment, the collaborative SE of other response surface experiments were less than 1, and the synergy of polyphenols was not obvious.