响应面优化超声波辅助酶解法制备金针菇ACE抑制肽

Optimization of ultrasonic-assisted enzymatic hydrolysis for preparation of ACE inhibitory peptides from Flammulina velutipes by response surface methodology

以金针菇(Flammulina velutipes)为原料,采用超声波辅助酶解法制备血管紧张素转化酶(ACE)抑制肽,为金针菇的深加工提供依据。筛选制备金针菇ACE抑制肽的酶,优化等电点沉淀法分离活性肽的最适pH。以ACE抑制率为响应值,开展液料比、超声时间、酶添加量等5个因素的单因素试验,设计四因素三水平的响应面试验。结果表明,制备金针菇ACE抑制肽的最佳蛋白酶为胰蛋白酶,沉淀活性肽的最佳pH为6.5。ACE抑制肽最佳制备条件为超声功率250 W,酶解温度37℃,酶解pH 8,液料比40∶1(mL/g),超声时间5 min,酶添加量为金针菇样品量的1.2%(g/g),酶解时间90 min。通过超滤分离法对ACE抑制肽进行了分级,并分析其活性。在此条件下,金针菇肽的ACE抑制率为(65.36±1.53)%;截留分子质量<3 kDa的肽ACE抑制率最高。

Angiotensin converting enzyme(ACE)inhibitory peptide was prepared from Flammulina velutipes by ultrasonic-assisted enzymolysis,providing the basis for further processing of Flammulina velutipes.The enzyme for preparing ACE inhibitory peptide of Flammulina velutipes was screened,and the optimal pH for separating active peptide by isoelectric point precipitation was optimized.With ACE inhibition rate as the response value,a single factor test was carried out with five factors,including liquid to material ratio,ultrasonic time,and enzyme dosage,and a response surface test with four factors and three levels was designed.The results showed that the best protease for preparing ACE inhibitory peptide of Flammulina velutipes was trypsin,and the best pH for precipitating active peptide was 6.5.The optimal preparation condition of ACE inhibitory peptide was as follows:ultrasonic power of 250 W,enzymolysis temperature of 37 ℃,enzymolysis pH of 8,liquid to material ratio of 40∶1(mL/g),and ultrasonic time of 5 min.Enzyme addition was 1.2%(g/g)of Flammulina velutipes sample,and enzymolysis time was 90 min.ACE inhibitory peptides were classified and their activity was analyzed using ultrafiltration separation method.Under this condition,the ACE inhibitory rate of Flammulina velutipes peptide was(65.36 ± 1.53)%;peptides with a molecular weight of <3 kDa had the highest ACE inhibition rate.