德氏乳杆菌QS306细胞壁蛋白酶的提取及纯化  

Extraction and Purification of Cell Envelope Protease from Lactobacillus Delbrueckii QS306

作　　者：于紫薇 双全[1] YU Ziwei;SHUANG Quan(College of Food Science and Engineering,Inner Mongolia Agricultural University,Hohhot 010018,China)

机构地区：[1]内蒙古农业大学食品科学与工程学院,内蒙古呼和法特010018

出　　处：《食品科技》2021年第5期8-13,共6页Food Science and Technology

基　　金：内蒙古自治区科技计划项目(2019GG362)。

摘　　要：以德氏乳杆菌QS306为研究对象,以酶活性为评价指标,通过单因素和正交试验,确定菌株QS306产细胞壁蛋白酶(Cell envelope protease,CEP)的最佳提取条件,并通过超滤浓缩、Sephadex G-75凝胶层析对CEP进行纯化。结果表明:在溶菌酶添加量为2 mg/mL、裂解温度为53℃、裂解时长为4.5 h的条件下菌株QS306的CEP活性达到最高,其酶活性为8.40 U/mL。在此最优提取条件下获得的粗酶液,经超滤浓缩及Sephadex G-75凝胶层析后,其比活力可达到109.02 U/mg,纯化倍数为3.74。用纯化后的CEP水解牛乳蛋白,水解液的血管紧张素转换酶抑制率(Angiotensin converting enzyme inhibition,ACEI)为31.50%。In this experiment,the cell envelope protease was extracted from Lactobacillus delbrueckii QS306.Taking enzyme activity as the evaluation index,orthogonal test analysis was carried out on the basis of single factor test to determine the best extraction conditions for CEP produced by Lactobacillus delbrueckii QS306.The CEP was purified by ultrafiltration concentration and Sephadex G-75 gel chromatography.The results showed that:Under the conditions of lysozyme dosage of 2 mg/mL,pyrolysis temperature of 53 ℃ and pyrolysis time of 4.5 h,the maximum CEP activity of Lactobacillus delbrueckii QS306 was 8.40 U/mL.The crude enzyme solution obtained under the optimal extraction conditions was concentrated by ultrafiltration,and after Sephadex G-75 gel chromatography,its specific activity reached 109.02 U/mg,and the purification multiple was 3.74.The purified CEP was used to hydrolyze milk protein,and the hydrolyzate ACE inhibition rate was 31.50%.

关 键 词：德氏乳杆菌 细胞壁蛋白酶 分离纯化 ACE抑制率 

分 类 号：TS201.3[轻工技术与工程—食品科学]