缢蛏蛋白肽制备工艺优化及其清除羟自由基作用

Optimization of the preparation of bioactive peptides from Sinonovacula constricta and its hydroxyl free radical scavenging activity

以缢蛏为试验材料,采用羟自由基清除率为评价指标,从胰蛋白酶、胃蛋白酶、木瓜蛋白酶、碱性蛋白酶和中性蛋白酶5种蛋白酶中筛选最适水解用酶,在单因素试验基础上使用响应面法优化酶解工艺条件,考察缢蛏蛋白肽的羟自由基清除能力并通过Sephadex G-15凝胶层析测定其分子质量分布。结果表明,碱性蛋白酶酶解制备的缢蛏蛋白肽清除羟自由基能力明显强于其他蛋白酶,优化后的碱性蛋白酶水解缢蛏蛋白工艺条件为底物浓度6mg/ml、加酶量3%、pH8.0、温度55℃、酶解时间4h,蛋白肽的羟自由基清除率为76.60%,IC50值为1.89mg/ml,蛋白肽中80%以上是分子质量小于1500Da的小分子肽。

Using Sinonovacula constricta as raw materials, optimum enzyme was selected from trypsin, pepsin, papain, alcalase and neutrase based on the hydroxyl free radical scaven- ging activity. Based on the single factor experiment, optimization of the hydrolysis conditions was conducted by the response surface methodology. The scavenging activity of hydroxyl free radical was investigated and the molecular weight of the enzymatic hydrolysates of S. constricta proteins was determined by a Sephadex G-15 gel column. The results showed that alcalase had the best hydrolytic effect and the optimum conditions for hydrolysis by alcalase were as follows. 6 mg/ml substrate,3% enzyme, pH 8.0,55 ℃, 4 h. The scavenging activity of hydroxyl free radical of enzymatic hydrolysates was 76.60% and the ICs0was 1.89 mg/ml. The molecular weight of over 80% bioactive peptides from S. constricta was less than 1 500 Da.