海地瓜蛋白酶解物类蛋白反应修饰及其对ACE活性的影响

Research on plastein reaction-basic modification of Acaudina molpadioidea protein hydrolysates and its effects on ACE activity

目的研究海地瓜酶解物类蛋白反应修饰及其对ACE活性的影响。方法采用复合酶酶解海地瓜体壁蛋白,得到具有降血压活性的酶解物,利用类蛋白反应进行修饰,考察酶的种类、底物浓度、温度、酶添加量对类蛋白反应的影响,得到不同修饰程度的产物,测定其ACE抑制活性。结果与结论经过类蛋白反应修饰后,显著提高了酶解液的ACE抑制活性。体系中游离氨基的减少量呈不规则变化,修饰产物的IC50值也呈不规则下降,其中反应1h和4h的修饰产物IC50值最低,分别是0.62mg.mL-1和0.75mg.mL-1。分析体系中游离氨基酸的组成,发现脯氨酸的结合能显著提高海地瓜体壁蛋白酶解物的ACE抑制活性。

Objective To investigate the plastein reaction-basic modification of Acaudina molpadioidea protein hydrolysates and its effects on ACE activity.Methods Acaudina molpadioidea protein hydrolysates with ACE inhibitory activity were prepared by complex enzymes and modified by plastein reaction.The effects of different kinds of enzymes and the addition level of enzymes,the concentration of Acaudina molpadioidea protein hydrolysates,temperature and time on the plastein reaction of hydrolysates were studied.Acaudina molpadioidea protein hydrolysates with different modification extents were prepared and the value of their ACE inhibitory activities were determined.Results and Conclusion The results indicated that the ACE inhibitory activity of Acaudina molpadioidea protein hydrolysates was improved significantly after being modified by plastein reaction.Modified Acaudina molpadioidea protein hydrolysates had a decrease in free amino groups irregularly and their IC50 decreased to 0.62 mg·mL-1 and 0.75 mg·mL-1 in 1 h and 4 h,respectively.The decrease of proline in the reaction system could significantly increase the ACE inhibitory activity of Acaudina molpadioidea protein hydrolysates.