产朊假丝酵母培养条件的优化研究

Optimization of Culture Conditions of Candida utilis

利用摇瓶发酵优化产朊假丝酵母的培养条件,并放大至5L发酵罐进一步优化,旨在获得更高的菌体量。摇瓶发酵试验结果表明:产朊假丝酵母的最适接种量为5%,(NH4)2SO4和KH2PO4的最佳浓度分别为5g/L和10g/L,发酵温度为28℃。此外,通过对5L发酵罐的进一步优化发现:当初始葡萄糖浓度为30g/L,发酵时间为10h时,以100mL/h的速度连续流加浓度为90g/L的葡萄糖母液10h,产朊假丝酵母的生物量及收率达到最大值,分别为24.01g/L和0.49g/g,明显高于分批发酵模式的16.39g/L和0.44g/g。

Flask fermentation is utilized to optimize culture conditions of Candida =tills, and then 5-L fermenter is optimized to acquire more biomass. The results of flask fermentation show that the highest biomass is only obtained if 5% inoculum is cultured at 28℃with the addition of 5 g/L （NH4）=SO4 and 10 g/L KH, PO4. On the other hand, the study of fed-batch fermentation in 5-L fermenter reveal that the biomass of 24.01 g/L and the yield of 0. 49 g/g are achieved only on a certain condition, where 30 g/L glucose is added to initialize and sustain the fermentation for 10 h, and then 90 g/L glucose is fed with another 10 h at the feeding rate of 100 mL/h. The data are much higher than those using batch fermentation as only 16.39 g/L biomass and 0.44 g/g yield.