Abstract:The marine protein oligopeptides were obtained by complex enzymatic hydrolysis method, and their physicochemical properties, amino acid composition and molecular weight distribution were analyzed. The antioxidant activity of marine protein oligopeptides was analyzed from four aspects including hydroxyl radicals, DPPH free radicals, superoxide anion radical scavenging ability and reducing ability. In addition, from the ACE inhibitory activity, their ability to lower blood pressure was explored. Marine protein oligopeptides had strong in vitro antioxidant capacity, and the semi-inhibitory concentrations (IC50 values) of hydroxyl radicals, DPPH free radicals and superoxide anion radicals were approximately 2.75, 4.7 mg/mL and 18.2 mg/mL, respectively. The reducing ability at the concentration of 20 mg/mL was equivalent to the ascorbic acid VC concentration of 0.04 mg/mL. In addition, marine protein oligopeptides showed a higher ACE inhibitory ability with the IC50 value of approximately 0.75 mg/mL. This experiment clarified that marine protein oligopeptides have good anti-oxidation and antihypertensive activities, which provided a certain reference basis for the development and utilization of nutrition and health food.