响应面法优化核桃降压肽的酶解工艺研究

Optimization of enzymatic hydrolysis of ACE in inhibition peptides from walnut protein by response surface method

本研究以低温脱脂核桃粕为原料,采用碱溶酸沉提蛋白后,分别用碱性蛋白酶、中性蛋白酶、木瓜蛋白酶和风味蛋白酶制备核桃多肽,以血管紧张素转化酶(Angiotensin-I-Converting Enzyme,ACE)抑制率和水解度为指标,选出酶解效果最好的酶,并且对其底物质量浓度、加酶量、酶解温度、酶解时间和p H进行单因素实验,在此基础上采用响应面实验优化其制备核桃降压肽的最佳水解工艺。结果表明:在底物质量浓度30g/L、加酶量8000U/g、酶解温度57℃和p H8.6的条件下水解3h,ACE抑制率可达64.32%,此时酶解液的水解度为21.57%。

In this paper,walnut protein, extracted form defatted walnut meal and then was separated by alkaline extraction-isoelectric precipitation technique, was hydrolyzed by four protease (alkaline protease, neutral protease,papain and flavor protease)for production of antihypertensive peptides.As an index,ACE inhibitory rate and the degree of hydrolysis were determined to select the proper enzyme with best enzymatic effect.Then single factor experiments were carried out to research the effects of the factors such as substrate concentration(g/L), enzyme dosage ( U/g ), hydrolysis time ( h ), hydrolysis temperature (℃) and pH. The response surface methodology was used to optimize conditions of the enzymatic hydrolysis.The results showed that the optimum conditions were substrate concentration 30g/L, enzyme dosage 8000U/g, temperature 57℃, pH8,6 and time of enzymatic hydrolysis 3h.The ACE inhibition rate could reach 64.32% and the degree of hydrolysis was 21.57%.