米根霉发酵生产L-乳酸钙条件的优化

摘要

Rhizopus oryzae strain As 3.3462 was applied to ferment lactate acid from glucose,and L-lactate acid calcium was produced using CaCO3 as neutralizer.The production process of L-lactate acid calcium was optimized.The results showed that when inoculation dose of spore was 1.8×104 ind.spore/mL and rotation speed at 200 r/min,the growth state of mycelium was well.The optimal fermentation conditions for higher L-lactate calcium were original glucose content in culture medium at 80 g/L and fermentation temperature at 34 ℃.According to pilot test,the productivity yield under the optimized conditions was very close to the theoretical value.The purification of the final L-lactate acid calcium product was higher than 99％; and the optical purity was 96％.%采用米根霉(Rhizopus oryzae)As 3.3462菌株发酵葡萄糖生产乳酸,以CaCO3为中和剂制备L-乳酸钙,优化种子培养的发酵条件.结果表明,孢子接种量1.8×104个孢子/mL、摇床转速为200 r/min时所得菌体生长形态较好.发酵培养基初始葡萄糖浓度80 g/L、发酵温度34℃时具有比较高的葡萄糖转化率.中试结果显示优化的发酵条件下L-乳酸钙产率与理论产率非常接近,得到的L-乳酸钙成品纯度高于99％,光学纯度达到96％.