带鱼ACE抑制肽的酶法制备及分离纯化

Enzymatic Preparation,Isolation and Purification of ACE Inhibitory Peptide from Hairtail

为有效利用带鱼资源,制备优质的血管紧张素转换酶(ACE)抑制肽,以ACE抑制率和水解度为评价指标,筛选出制备带鱼ACE抑制肽的最适蛋白酶。通过单因素和响应面优化蛋白酶的酶解工艺条件,分析优化后的带鱼ACE抑制肽的分子质量和氨基酸组成。采用超滤和Prep-HPLC对ACE抑制肽分离纯化,获得具有最高ACE抑制率的活性组分。结果表明,复合蛋白酶是制备带鱼ACE抑制肽的最佳蛋白酶,优化后的最佳酶解参数为水解时间3 h,温度45℃,加酶量5000 U/g,p H 7.0。在此条件下带鱼ACE抑制肽的理论抑制率为80.15%,实际值为80.43%,IC50为0.33 mg/mL,相对分子质量主要分布在1000 u以下。带鱼ACE抑制肽的氨基酸组成模式合理,鲜味氨基酸和疏水性氨基酸含量较高。经Prep-HPLC分离得到6个组分,其中组分5的ACE抑制活性最高,IC_(50)为0.11 mg/mL。本研究为带鱼ACE抑制肽的制备提供了技术支持。

In order to utilize the hairtail resources effectively and prepare high-quality angiotensin-converting enzyme(ACE)inhibitory peptide,the most suitable protease for the preparation of hairtail ACE inhibitory peptide was screened using ACE inhibition rate and hydrolysis degree as evaluation indexes.The enzymatic process conditions were optimized by single factor and response surface.The optimized hairtail ACE inhibitory peptide was analyzed for molecular weight and amino acid composition.The ACE inhibitory peptide was further purified by ultrafiltration and Prep-HPLC,and the active fraction with the highest ACE inhibition rate was obtained.The results showed that the protemax was the best protease for the preparing ACE inhibitory peptide,and the optimized process parameters were obtained as follows:enzymatic hydrolysis time of 3 h,hydrolysis temperature of 45°C,enzyme dosage 5000 U/g and pH 7.0.Under this condition,the theoretical ACE inhibition rate was 80.15%,the actual value was 80.43%,and the IC50was 0.33 mg/mL.The relative molecular weight of the ACE inhibitory peptide was mainly distributed below 1000 u.The amino acid composition pattern of the hairtail ACE inhibitory peptide was reasonable,with high content of fresh and hydrophobic amino acids.The six fractions were separated by ultrafiltration and Prep-HPLC,and the highest activity was obtained for fraction 5 with an IC50of 0.11 mg/mL.This study provides a theoretical basis for the application of hairtail in functional foods for hypertension.