蚕蛹蛋白抗氧化肽的制备及其纯化

以DPPH自由基清除率为指标,采用正交试验,优化Alcalase酶解蚕蛹蛋白制备抗氧化肽的工艺条件;采用超滤、DEAE-52纤维素柱层析,以及Sephadex G-50柱层析分离纯化蚕蛹蛋白抗氧化肽。试验结果表明,酶解液制备蚕蛹蛋白抗氧化肽的最优工艺条件为:酶解温度30℃,pH值7.5,时间20min,底物质量分数3%,加酶量3.5%。Mr≤5ku时,组分有很强的体外抗氧化活性,从Mr≤5ku组分中获得了5个抗氧化肽组分,它们的体外抗氧化活性大小依次为:组分Ⅱ>组分Ⅲ>组分Ⅰ>组分Ⅴ>组分Ⅳ。

Preparation and Purification of Antioxidant Peptides from Silkworm Pupae Protein

Alcalase enzymolysis technology for production of antioxidant peptides from silkworm pupae protein,in which scavenging 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical is taken as response value,is optimized with orthogonal test methodology.Furthermore,the antioxidant peptides are separated and purificated from Alcalase hydrolysates of silkworm pupae protein by ultrafiltration,DEAE-52 cellulose column chromatography and Sephadex G-50 column chromatography.The results show that the optimum conditions of Alcalase hydrolysis are temperature 30 ℃,pH 7.5,time 20 min,substrate concentration 3%,enzyme dosage 3.5%.Ultrafiltration results show that the Alcalase hydrolysate of molecular weight (Mr) ≤5 ku has strong in vitro antioxidant activitives.Five fractions (fractionⅠ,fraction Ⅱ,fraction Ⅲ,fraction Ⅳ and fraction Ⅴ) with in vitro antioxidant activitives are obtained from the Alcalase hydrolysate of Mr≤5 ku,and their in vitro antioxidant activitives is decreased in the following order: fraction Ⅱ>fraction Ⅲ>fractionⅠ>fraction Ⅴ>fraction Ⅳ.