Abstract:In order to study the antioxidant activities of different Tartary buckwheat polypeptides，to develop related products and increase the added value of Tartary buckwheat.In this experiment，Tartary buckwheat protein was extracted by alkali extraction，acid sinking enzyme assisted method，and then hydrolyzed by trypsin and alkaline protease.The double enzymatic hydrolysis conditions were optimized by response surface methodology and set as following：the protein concentration of 5 mg/mL，enzyme dosage of 0.1%，mass ratio of alkaline protease to trypsin was 1∶3，pH was 7.5，enzymolysis temperature of 55℃and enzymolysis time of 3 h.The antioxidant activity of the double enzymolysis products was detected.The results showed that the scavenging rates of superoxide anion radical of chuanqiao NO.1 and yunku NO.3 were 97.23% and 96.45%，respectively.However，chuanqiao NO.1 and miqiao showed high scavenging ability on ABTS+and DPPH free radicals.The scavenging rates on ABTS+were 51.54% and 54.41%，respectively，and those on DPPH were 87.35% and 84.91%，respectively.The scavenging rates of hydroxyl radical of diku NO.2 and chuanqiao NO.1 were 90.47% and 91.32%，respectively.