枯草芽孢杆菌对金针菇发酵液蛋白质降解研究

Study on the Degradation of Protein in Flammulina velutipes Fermentation Broth by Bacillus subtilis

探究枯草芽孢杆菌对发酵液中金针菇子实体蛋白降解规律,为开发金针菇为原料的益生菌保健品提供理论支持。以金针菇子实体为主要原料配制发酵培养液,接入枯草芽孢杆菌纯培养物种子液,25℃,35℃和45℃下分别进行发酵培养,动态监测0~96 h内发酵液中蛋白质含量变化。结果表明,发酵温度对发酵液中子实体蛋白降解率有明显影响,发酵至96 h时发酵液中子实体蛋白降解率分别为51.20%,69.07%和79.91%,子实体蛋白的降解程度随发酵温度的提高而增大,且发酵温度决定了降解程度的峰值。在0~96 h的测试时间范围内,高温发酵菌体数量变化幅度远远大于低温条件,35℃,45℃的发酵条件菌体数量呈先增加后降低再次增加而后降低的二次增长现象,而25℃发酵未呈现二次增殖现象。高温发酵温度有利于提高金针菇发酵液中蛋白质等大分子的降解率,缩短发酵时间,提高发酵生产效率。

The rule degradation of protein in Flammulina velutipes fermentation broth of Bacillus subtilis was studied in order to provide theoretical support for the development of probiotic health care products of raw materials. Access pure culture of the Bacillus subtilis to Flammulina velutipes as the main raw material preparation of culture liquid, in 25℃, 35 ℃ and 45 ℃ respectively by fermentation, the protein content and Bacillus subtilis colony number in fermentation liquid 0-90 h were determined. The results showed that the fermentation temperature had a significant effect on the degradation rate of protein in Flammulina velutipes. The degradation rate of protein in fermentation broth at 96 h was 51.20%, 69.07% and 79.91%. The fermentation temperature determined the peak value of the degree of degradation. Sporophore protein degradation degree increased with the increase of fermentation temperature and fermentation temperature determined the degree of degradation of the peak. In 0--96 h test time range, the change amplitude of bacteria quantity was far greater under high temperature fermentation than under low temperature. 35 ℃, 45 ℃ fermentation conditions of bacteria quantity were increased firstly and decreased after increased again and then decreased secondary growth phenomenon, and 25 ℃ fermentation did not show the phenomenon of secondary growth. The higher fermentation temperature was beneficial to improve the degradation rate of protein and other macromolecules in Flammulina velutipes fermentation broth, shorten the fermentation time and improve the production efficiency.