产蛋白酶波茨坦短芽孢杆菌的鉴定及产酶条件优化

Identification of a Protease Producing Brevibacillus borstelensis Strain and Optimization of Enzyme Production Conditions

摘要:

该研究旨在提高一株环境分离菌株的产酶效率，为后续菌株及其蛋白酶的应用提供前期实验基础。通过水解圈法初步检测菌株S8的产蛋白酶能力，并通过16S rRNA序列比对确认其为波茨坦短芽孢杆菌。通过单因素试验确定了最佳培养条件和培养基添加成分。并采用Plackett-Burman设计和最陡爬坡试验对培养条件和培养基进行响应面优化。优化结果显示，在发酵时间为38.70 h、菌液接种量为1.84%（V/V）、发酵温度为35 ℃、酵母粉添加量为23.70 g/L、胰蛋白胨添加量为11.70 g/L、MgSO4添加量为20.20 g/L的条件下，菌株的产酶活力可达到114.79 U/mL，相比优化前提升了209.70%。研究结果为该菌株的后续发酵应用提供了科学数据。

Abstract:

In order to improve the enzyme production efficiency of an environmentally isolated strain, and provide a preliminary experimental basis for the subsequent application of the strain and its protease, the protease production ability of strain S8 was preliminarily detected using the hydrolysis circle method, and its identity as Brevibacillu sborstelensis was confirmed by comparing the 16S rRNA sequences. The optimal culture conditions and medium components were determined through single-factor experiments. Finally, the culture conditions and medium were further optimized using response surface methodology with the help of Plackett-Burman design and the steepest ascent method. The optimization results showed that the optimal conditions are as follows: a fermentation time of 38.70 h, an inoculum size of 1.84% (V/V), a fermentation temperature at 35 ℃, a yeast powder addition of 23.70 g/L, a pancreatic digest of casein addition of 11.70 g/L, and a MgSO4 addition of 20.20 g/L. The resulting enzyme production activity of the strain reached 114.79 U/mL, which was 209.70% higher than that under non-optimized conditions. The results of this study provide scientific data for the subsequent fermentation application of this strain.