摘要
试验旨在从人工养殖的黄鳝体内分离高产蛋白酶菌株,为后续微生物蛋白酶的制备和微生态制剂的开发提供菌种资源,以解决黄鳝摄食率低、消化不完全及水体氮污染等问题。通过采用脱脂奶粉培养基透明圈法初筛和Folin-酚法测定酶活复筛相结合的方式筛选人工养殖黄鳝肠道中的高产蛋白酶菌株,通过溶血试验与药敏试验检测菌株安全性,并进行常规生化和分子生物学鉴定。通过单因素和正交试验优化其发酵条件,筛选到一株高产蛋白酶、产过氧化氢酶的菌株Ma-4,初步鉴定其为阿氏芽孢杆菌(Bacillus aryabhattai)。该菌株最适产酶条件为发酵时间48 h、发酵温度36℃、可溶性淀粉添加量15 g/L、牛肉浸粉添加量15 g/L和pH值6.0。优化后菌株酶活力为288.14 U/mL,较优化前提高了3.34倍。研究表明,菌株Ma-4为高产蛋白酶、产过氧化氢酶、不溶血、不耐药的阿氏芽孢杆菌,该菌株为开发黄鳝微生态制剂开拓了菌种资源。
In order to solve the problems of the low feeding rate,incomplete digestion of Monopterus albus,and nitrogen pollution of water,the study aimed to isolate high-yield protease producing strains from artificially cultivated Monopterus albus,which will provide strain resources for the production of microbial proteases and the development of probiotics in the future.High-yield protease producing strains were preliminarily isolated from the artificially cultivated Monopterus albus by the combination of the transparent circle method of skimmed milk powder culture medium for primary screening and the Folin-phenol method for secondary screening to measure protease activity.The safety of the strains was tested through a hemolysis test and a drug sensitivity test,and the strains were identified by adopting a combination method of the physiological and biochemical characteristics of the strain.The fermentation conditions for protease production were optimized through single factor and orthogonal experiments.A high-yield protease producing strain named Ma-4 was screened,and it was identified as Bacillus aryabhattai,which can also produce the hydrogen peroxide enzyme.Its optimal enzyme production conditions were the fermentation time of 48 h,the fermentation temperature of 36℃,the optimal amount of soluble starch of 15 g/L,the optimal amount of beef powder of 15 g/L,and the pH value of 6.0.After optimization,the enzyme activity increased to 288.14 U/mL,representing a 3.34-fold improvement.The study indicates that the strain Ma-4 is a high protease-producing,catalase-producing,non-hemolytic and drug-resistant Bacillus aryabhattai,which can provide strain resources for the development of micro-ecological preparations of Monopterus albus.
作者
郑菲菲
何鑫
尹丽
张靖悦
祝东梅
高坚
宋玉峰
赵玉华
ZHENG Fei-fei;HE Xin;YIN Li;ZHANG Jing-yue;ZHU Dong-mei;GAO Jian;SONG Yu-feng;ZHAO Yu-hua
出处
《饲料研究》
CAS
北大核心
2024年第3期73-78,共6页
Feed Research
基金
国家自然科学基金面上项目(项目编号:32273156)
湖北省大学生创新创业训练计划项目(项目编号:S202110504216)。
关键词
黄鳝
阿氏芽孢杆菌
筛选鉴定
安全性评价
发酵条件优化
Monopterus albus
Bacillus aryabhattai
screening and identification
safety evaluation
optimization of fermentation conditions
