Abstract:In order to improve the resource utilization of mung bean protein, the waste produced in the mung bean starch production, the optimal conditions for preparing mung bean antioxidant peptides by enzymatic method were studied, and their antioxidant activity was also investigated. The enzymatic hydrolysis of mung bean protein was optimized by different proteases or their complex enzymes, with other factors examined including the reaction time and the enzyme amount. The antioxidant capacity of the hydrolyzed polypeptide was tested by in vitro antioxidant experiment. The optimal reaction conditions were finally established as follows: 2% of neutral protease and 3% of substrate were used for 3 h hydrolysis at pH 7 and 50 ℃. The resulted mung bean peptide solution had a DPPH free radical scavenging rate of （91.58±2.44）% with a mass concentration of 5 mg/mL, showing strong reducing ability. Five separated fractions were obtained by purification using gel chromatography column. The small molecule peptide component 5 had the strongest antioxidant capacity, which was higher than other large molecule peptides and unseparated peptides.
