脱脂米糠抗氧化肽的制备工艺研究

Preparation of antioxidant peptide from defatted rice bran

为了得到脱脂米糠抗氧化肽的最佳制备工艺,研究了胰蛋白酶、胃蛋白酶、中性蛋白酶、碱性蛋白酶、木瓜蛋白酶酶解脱脂米糠蛋白的进程特性以及不同的酶解条件对脱脂米糠抗氧化肽活性的影响。从5种蛋白酶中筛选出最合适的酶,通过单因素实验考察了底物浓度、加酶量、pH、温度以及时间对酶解产物水解度和ABTS自由基清除率的影响,在单因素实验的基础上,以酶解产物的ABTS自由基清除率为响应值,进行Box-Behnken中心组合实验。结果表明:选用碱性蛋白酶制备脱脂米糠抗氧化肽效果最好;最佳酶解工艺条件为加酶量1.8%、温度50℃、时间276 min、pH9.0、底物浓度5%;在最佳酶解工艺条件下,所得脱脂米糠抗氧化肽对ABTS自由基清除率可达71.85%。

In order bran, the progress to obtain the optimal preparation conditions of antioxidant peptide from defatted rice characteristics of Papain and the effect of enzymatic enzymatic hydrolysis with Trypsin, Pepsin, Neutrase, Alcalase and hydrolysis conditions on antioxidation activity of antioxidant peptide from defatted rice bran were investigated. The best protease was chosen from these proteases and the effects of substrate concentration, enzyme dosage, pH, temperature and time on the degree of hydrolysis and the scavenging rate on ABTS radical were studied by single factor experiment. Based on single factor experiment, response surface methodology was designed with the scavenging rate of hydrolysate on ABTS radical as indicator. The results showed that Alcalase was the optimal protease for preparation of antioxidant peptide from defatted rice bran and the optimal enzymatic hydrolysis conditions were obtained as fol- lows： enzyme dosage 1.8%, temperature 50℃, time 276 min, pH 9. 0, substrate concentration 5%. Under these conditions, the antioxidant peptide from defatted rice bran exhibited strong scavenging activity on ABTS radical and the scavenzinz rate reached up to 71.85%.