瑞士乳杆菌蛋白酶水解乳清蛋白制备ACE抑制肽的条件优化

Optimization of Hydrolysis Conditions for Production of Angiotensin-I Converting Enzyme (ACE) Inhibitory Peptide from Whey Protein Using Proteinases of Lactobacillus helveticus

目的:本实验以WPC-80乳清浓缩蛋白为原料,对瑞士乳杆菌蛋白酶水解乳清蛋白产生血管紧张素转移酶(ACE)抑制肽工艺条件进行研究。方法:通过单因素条件和响应面方法研究水解pH值、水解温度、酶与底物比、底物浓度和水解时间对水解度和ACE抑制率的影响。结果:研究发现,五个工艺条件对ACE抑制肽的产生都有影响,通过响应面法分析,确定瑞士乳杆菌蛋白酶酶解乳清蛋白的最佳水解条件为:[E]/[S]0.6%、底物浓度6%、pH9.18、温度38.90℃,时间8.0h,在此条件下水解,产物ACE抑制率达到92.21%,IC50为0.375mg/ml,水解度为18.76%。结论:应用响应面方法优化水解工艺条件是可行的。

Objective： To optimize the preparation technology of ACE inhibitory peptide from WPC-80 whey protein concentrate hydrolyzed by the proteases produced by Lactobacillus helveticus using response surface methodology. Methods： Through single-factor test and response surface methodology, the effects of five enzymatic hydrolysis conditions including temperature, pH, enzyme to substrate （[E]/[S]） ratio, substrate concentration and time on the degree of hydrolysis （DH） of WPC-80 whey protein concentrate and the ACE inhibitory activity were investigated. Results： All of five factors affected the production of ACE inhibitory peptide, and among them temperature, pH and [E]/[S] ratio were the key factors. The optimum temperature, pH, [E]/[S] ratio, substrate concentration and time were 38.90℃, 9.18, 0.6%, 6% and 8.0 h, respectively. Under these conditions, the ACE inhibitory activity was 92.21%, its IC50 was 0.375mg/ml, and the DH was 18.76%. Conclusion： The response surface methodology is feasible to optimize the enzymatic hydrolysis conditions for ACE inhibitory pepfide preparation.