Zhongguo youzhi (Apr 2024)
酶解法制备核桃谷蛋白-1 ACE抑制肽的工艺优化Preparation of ACE inhibitory peptide from walnut glutelin-1 by enzymatic hydrolysis
Abstract
为获得优质的核桃蛋白血管紧张素转化酶(ACE)抑制肽的制备原料及优化其制备工艺,采用连续提取法从脱脂核桃粕中依次分离出清蛋白、球蛋白、醇溶蛋白、谷蛋白-1和谷蛋白-2 5种组分蛋白,测定5种组分蛋白的占比及ACE抑制率,以ACE抑制率最大的组分蛋白作为原料采用酶解法制备ACE抑制肽,在筛选出最适酶解用酶基础上,采用单因素试验与响应面试验优化酶解制备核桃蛋白ACE抑制肽的工艺。结果表明:5种组分蛋白中谷蛋白-1占比仅次于谷蛋白-2,且其ACE抑制率最高,以核桃谷蛋白-1为原料,在筛选出胃蛋白酶作为酶解用酶基础上,经工艺优化得到最优的酶解法制备核桃谷蛋白-1 ACE抑制肽的工艺条件为酶解温度46 ℃、酶解时间6 h、酶用量4.2%(以底物质量计)、酶解pH 1.6,在该条件下所得核桃谷蛋白-1 酶解液的ACE抑制率为(50.08±2.34)%。因此,核桃谷蛋白-1经胃蛋白酶酶解可生产ACE抑制活性较高的核桃多肽。In order to obtain high-quality raw materials for the preparation of angiotensin converting enzyme (ACE) inhibitory peptide from walnut protein and optimize its preparation process, five component proteins including albumin, globulin, prolamin, glutelin-1 and glutelin-2 were separated from defatted walnut meal using continuous extraction method in turn. The proportion and ACE inhibition rates of the five component proteins were determined.The component protein with the largest ACE inhibition rate was used as raw material to prepare ACE inhibitory peptide by enzymatic hydrolysis. On the basis of selecting the optimal enzyme, the enzymatic conditions for the preparation of walnut protein ACE inhibitory peptide were optimized by single factor experiment combined with response surface methodology.The results showed that the proportion of glutelin-1 in the five component proteins was second only to glutelin-2, and its ACE inhibition rate was the highest. With walnut glutelin-1 as raw material and pepsin as enzyme, the optimal enzymatic hydrolysis preparation conditions of walnut glutelin-1 ACE inhibitory peptide were obtained as follows: enzymolysis temperature 46 ℃, enzymolysis time 6 h, enzyme dosage 4.2%(based on the mass of substrate), and enzymolysis pH 1.6. The ACE inhibition rate of the enzymatic hydrolysate obtained under the optimal conditions was (50.08±2.34)%. Enzymatic hydrolysis of walnut glutelin-1 by pepsin can produce walnut polypeptides with higher ACE inhibitory activity.
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