一株豆粕发酵高产蛋白酶芽孢杆菌的筛选及特性研究OA

Soybean peptide made from soybean meal is a new protein modification product with better quality,which is widely used in pharmaceutical,food,cosmetics,feed preparation,and plant cultivation.At present,the production of soybean peptides by microbial fermentation is regarded as the most advanced method.In this study,a Bacillus strain with high protease production was selected from the intestinal contents of sea cucumber,and the conditions of protease production and liquid fermentation of soybean meal were optimized.The results showed that the strain was Bacillus velezensis(Bacillus DLH-1).When the medium composition was 2%beef paste,0.75%yeast powder and 1%NaCl,the culture temperature was 35℃,the initial pH 7.0,the inoculation amount was 5%and the culture time was 33 h,the proteinase-producing activity was 131.309 U/mL,which was 1.94 times higher than that before optimization.It was found that the soybean meal could be effectively hydrolyzed under the conditions of 4%inoculation amount,1:10 ratio of material to water,36 h fermentation hydrolysis time,45℃fermentation hydrolysis temperature and initial pH 6.0,and the polypeptide content was 1.76 times higher than that before optimization.The aim of this study was to provide high performance bacteria source for soybean meal fermentation to produce protein feed or fertilizer,and provide help for the development and utilization of soybean meal and the improvement of economic benefits of related enterprises.