摘要
从大学食堂污水中筛选出1株高产蛋白酶菌株CL-10,通过生理生化实验以及16S rRNA测序鉴定为解淀粉芽孢杆菌。以廉价菜籽粕为氮源,以蛋白酶活力为指标,通过对培养基成分单因素试验探讨不同因素对发酵产蛋白酶的影响,在此基础上,通过响应面优化菜籽粕、玉米粉、麸皮的含量。结果表明:最优产酶条件为菜籽粕质量分数6.1%、玉米粉质量分数4.4%、麸皮质量分数3.2%、吐温20体积分数0.7%、ZnSO4·7H2O质量分数0.2%,在此条件下,蛋白酶活力的验证值为6385.1 U/mL,相比基础发酵培养基酶活力提高了1.35倍,平均氮源成本降低了54.6%。该工艺具有酶活高、成本低、操作简单的特点,为蛋白酶的生产和菜籽粕的资源化利用提供一定的指导。
In this study,a strain with the capability of producing a high yield of protease,named CL-10,was isolated from the sewage of a canteen in Nanchang University and was identified as Bacillus amyloliquefaciens through physiological and biochemical tests and 16S rRNA sequencing.Rapeseed meal was used as a cheap nitrogen source to produce protease by the strain.The selection and optimization of medium constituents as well as their levels for improved production of protease were carried out using one-factor-at-a-time(OFAT)method combined with response surface methodology(RSM).Rapeseed meal,corn meal and wheat bran levels were selected as independent variables for Box-Behnken design.As a result,the optimal levels for rapeseed meal,corn flour,wheat bran,Tween 20 and ZnSO4·7H2O were determined as 6.1%,4.4%,3.2%,0.7%(V/V),and 0.2%,respectively.Confirmatory experiments performed under these conditions yielded a maximum protease activity of 6385.1 U/mL,which was increased 2.35-fold compared with the basal fermentation medium,accompanied by a 54.6%reduction in the average cost of nitrogen source.The established process had the advantages of producing high enzymatic activity,low cost,and simple operation.Our results can guide the resource utilization of rapeseed meal for the production of protease.
作者
陈茏
杨俊
马毛毛
吴莎莎
余平
曾哲灵
CHEN Long;YANG Jun;MA Maomao;WU Shasha;YU Ping;ZENG Zheling(School of Food Science and Technology,Nanchang University,Nanchang 330031,China;State Key Laboratory of Food Science and Technology,Nanchang University,Nanchang 330047,China;School of Environmental and Chemical Engineering,Nanchang University,Nanchang 330031,China)
出处
《食品科学》
EI
CAS
CSCD
北大核心
2021年第4期115-121,共7页
Food Science
基金
国家自然科学基金青年科学基金项目(31701651)
国家重点实验室目标导向项目(SKLF-ZZA-201610)
南昌大学研究生创新专项(CX2018111)。
关键词
菌种筛选
蛋白酶
解淀粉芽孢杆菌
菜籽粕
响应面优化
strain screening
protease
Bacillus amyloliquefaciens
rapeseed meal
response surface optimization
