酶解刺参内脏蛋白制备抗氧化肽的研究

对刺参内脏所含的内源蛋白酶的性质进行了初步研究,在此基础上分析和比较了利用内源蛋白酶和外源蛋白酶酶解内脏蛋白制备抗氧化肽的工艺。刺参内脏主要含有四种内源蛋白酶,最适pH分别为2.0、5.0、8.0和12.0。以羟自由基和超氧阴离子自由基清除率为指标,比较了内源蛋白酶和八种外源蛋白酶酶解内脏蛋白制备抗氧化肽的效果,结果表明菠萝蛋白酶为最佳用酶;用正交实验L9(34)对其水解条件进行优化,确定最佳酶解条件为:pH7.8、温度35℃、加酶量5.0g/100g、酶解时间1h,在此条件下所得酶解液对羟自由基和超氧阴离子自由基的清除率分别为79.15%和28.57%。 

Study on the preparation of antioxidant peptide from sea cucumber ( Stichopus japonicus) visceral protein by enzymolysis

Proteases from sea cucumber (Stichopus japonicus) viscera have been studied.Casein digestion assay revealed acidic proteases with optimum activity at pH2.0 and pH 5.0, and alkaline proteases with optimal activity at pH8.0 and 12.0, respectively.Sea cucumber visceral protein were hydrolyzed by endogenous proteases alone or one of eight different exogenous proteases (flavourzyme, bromelain, papain, neutral protease, alkaline protease, trypsin, acid protease and pepsin) to produce the antioxidative hydrolysates.Bromelain has shown efficient hydrolysis for sea cucumber visceral protein to obtain the hydrolysates possessing the highest radical scavenging activity, and its optimum hydrolysis conditions were determined by orthogonal experimental design method as follows: pH value 7.8, temperature 35℃, dosage of enzyme 5.0g /100g, and time 1h, under which the scavenging rate of hydroxyl radical and superoxide anion radical were 79.15% and 28.57%, respectively.