碳、氮源对纳豆芽孢杆菌R127发酵产维生素K2的影响

Effects of carbon and nitrogen source on vitamin K2 production by Bacillus subtilis natto R127

维生素K2是一类重要的脂溶性凝血维生素,在凝血、抗骨质疏松等方面具有重要作用。以本实验室自主筛选的纳豆芽孢杆菌(Bacillus subtilis natto)R127发酵生产维生素K2,考察不同含量的碳源、氮源对纳豆芽孢杆菌生长、底物消耗和维生素K2合成能力的影响,并探究了维生素K2的分泌情况。结果表明,50 g/L甘油质量浓度最佳,K2产量达到15.8 mg/L;氮源浓度与生物量成反比,与维生素K2合成量呈正比;此外,在发酵过程中,一部分维生素K2以水溶性的形式分泌到细胞外,分泌率约68.8%。

Vitamin K2 is an essential lipid-soluble coagulation vitamin that plays an important role in blood clotting and anti-osteoporosis. We studied the effects of different content of carbon and nitrogen source on the growth of Bacillus subtilis natto,a Vitamin K2 producer screened by our laboratory.Factors studied include substrate consumption and secretion of vitamin K2.Results show that the optimal glycerol concentration was 50 g/L, and the yield of vitamin K2 reached 15. 8 mg/L. An inverse correlation was observed between biomass and the concentration of nitrogen source,whereas the yield of vitamin K2 was proportional to the nitrogen concentration. In addition, vitamin K2 was a water-soluble compound metabolite in the fermentation process,the secretory rate was about 68. 8%.