关键词: 草鱼鱼鳞, 酶解, 多肽, 抗氧化性, 胃肠消化

Abstract: [Objective] In this paper, antioxidant peptides were hydrolyzed from grass carp fish scale by the alkaline protease,and its stability was discussed. [Merhods] Optimum hydrolysis condition of alcalase enzyme was investigated with single factor experiment and orthogonal exper- iment and antioxidant peptides obtained by enzymatic hydrolysis were tested in vitro gastrointestinal digestion expetiment. [Results]The results showed that the optimum values of temperature, enzyme dosage, solid-to-water ratio and reaction time were 60 ℃, 1:15(g/m L), 800 U/g and 4 h. The polypeptide content’s scavenging rates against hydroxyl free radicals was 87.51% under these conditions. Compared with Vc, the research studied the different concentrations of antioxidant peptide DPPH radical scavenging capacity, superoxide anion radical scavenging capacity. Results showed that with the increase of antioxidant peptide concentration, the DPPH radical scavenging ability and the ultra oxygen anionremoval capacity increased. When the concentration was 0.5 mg/mL, scale antioxidant peptide on DPPH radical scavenging capacity reached 81.1% of Vc an d its clearance rates against superoxideanion free radicals was 98.97%. In the gastrointestinal digestion process, the first 4 h, gastrointes-tinal digestion was beneficial tosuper oxygen anion scavenging ability, and the scacenging activity was 100%, after 4 h, the ultra oxygen anion clearance rate dropped significantly, and in the whole process of gastrointestinal digestion, the hydroxyl radical scavenging ability was bad. [Conclusion] Antioxidant peptides preparaed by alkaline protease hydrolysis of grass carp fish scales had good antioxidant activity and stability.

Key words: Grass carp fish scales, hydrolysis, polypeptide, antioxidant activity, gastrointestinal digestion