添加芽孢杆菌对豆粕固体发酵的影响

以豆粕为主要发酵材料，枯草芽孢杆菌JK2为发酵菌种，进行豆粕固体发酵。为了分析添加芽孢杆菌对发酵豆粕营养特性及细菌多样性的影响，发酵过程检测豆粕的温度和pH，及发酵前后豆粕的C/N、棕榈酸、亚油酸和细菌群落的变化。结果表明，添加芽孢杆菌可以促进豆粕发酵升温，降低pH，提高棕榈酸含量，增加发酵豆粕中细菌的数量和种类。细菌多样性分析显示：厚壁菌门细菌是发酵豆粕中的优势菌；发酵后的豆粕中，乳杆菌属的鼠李糖乳杆菌（Lactobacillus rhamnosus）、桥乳杆菌（L. pontis）和发酵乳杆菌（L. fermentum）的相对含量升高，成为发酵豆粕的优势菌。添加芽孢杆菌能提高豆粕中乳酸菌的含量和多样性，降低肠杆菌属、葡萄球菌属和明串珠菌属等条件致病菌的含量。

Effects of Bacillus on solid state fermentation of soybean meal

With Bacilus subtitles JK2 as the fermentation bacteria, the solid state fermentation of soybean meal was carried out. The main objective of this study was to investigate the effects of the addition of bacillus on the nutritional properties and bacterial diversity of fermented soybean meal. In the light of the above considerations, temperature and pH of the soybean meal during the fermentation process was detected every day. Changes of C/N, palmitic acid, linoleic acid and bacterial communities were also overserved. The results show that bacillus JK2 can promote the rising of fermentation temperature, reduce pH and increase the content of palmitic acid in solid state fermentation of soybean meal. At the same time, the richness and diversity of bacteria also increased. The result of high-throughput sequencing showed that phylum Firmicutes was the dominant bacteria, Lactobacillus rhamnosus, L. pontis and L. fermentum were the predominant bacteria in fermented soybean meal. soybean meal fermented with B. subtitles JK2 can improve the content and diversityof lactic acid bacteria, meanwhile reduce the content of pathogenic bacteria such as Enterococus, Staphylococcus and Leuconostoc.