氨水中和Lactobacillus delbrueckiisubsp. lactis BME5-18M发酵生成L-乳酸铵的研究

Study on Fermentation of Lactobacillus delbrueckii subsp. lactis BME5-18M with Ammonia as a Neutralizer

实验确定了Lactobacillusdelbrueckiisubsp lactisBME5 1 8M接种的最佳种龄为 2 4h。以氨水取代传统的中和剂碳酸钙中和发酵生成的乳酸、调控发酵液的pH ,考察了不同pH值对菌体生长和产酸的影响 ,确定了菌种生长和产酸的较适pH值为 6 5。考察了底物流加速度对菌种生长和产酸的影响 ,对间歇和流加发酵时菌体的生长量和产酸量进行了动力学关联。在较适pH值 6 5和较佳流加速度 2 5mL/h条件下 ,乳酸的产量可达到 1 36 8g/L ,产率为 1 71g /(L·h)。

The optimal inoculums age of Lactobacillus delbrueckii subsp lactis BME5 18M is 24h Fermentation processes of Lactobacillus delbrueckii subsp lactis BME5 18M with ammonia as a Neutralizer were developed Effects of pH on the production of biomass and lactic acid in batch culture were studied at first, and the microorganism can gain the highest biomass density andlactic acid production at pH 6 5 The appropriate fed batch speed of glucose(600 g/L) is 25 mL/h at pH 6 5 Kinetics functions between lactic acid production and biomass density are presented for batch fermentation and fed batch fermentation at pH 6 5 respectively The production and productivity of lactic acid can reach 136 8g/L and 1 71 g/(L·h) at the preferable condition of pH 6 5 and 25 mL/h fed batch speed