酵母菌利用糖蜜发酵产麦角甾醇的工艺条件优化  

Improving ergosterol production from molasses by Saccharomyces cerevisiae

作　　者：王绍杰[1,2] 郭雪娜[1] 何秀萍[1] 张博润[1] 

机构地区：[1]中国科学院微生物研究所酵母菌分子遗传与育种实验室,北京100101 [2]中国科学院大学,北京100049

出　　处：《生物工程学报》2013年第11期1676-1680,共5页Chinese Journal of Biotechnology

基　　金：中国科学院微生物研究所科技成果转化基金资助~~

摘　　要：麦角甾醇是由酵母菌产生的具有重要经济价值的代谢产物。为了提高酵母菌利用糖蜜发酵生产麦角甾醇的产量,通过响应面分析法优化了发酵培养基配方,并在5 L发酵罐对发酵过程pH控制和底物流加补料方式进行了优化。结果表明,利用优化后的发酵培养基,即糖蜜总糖40 g/L,KH2PO41 g/L,K2HPO41.86 g/L,CuSO4·5H2O 17.5 mg/L,FeSO4·7H2O 13.9 mg/L,MgSO4·5H2O 12.3 mg/L,玉米浆10 mL/L,麦角甾醇产量比优化前提高了29.5%;利用恒定pH控制策略,在5 L发酵罐进行分批发酵,使麦角甾醇产量提高了62.1%;进一步采用底物流加补料策略,使麦角甾醇产量达到1 953.85 mg/L,是分批发酵的3.2倍,而且麦角甾醇产率比分批发酵提高了42.7%。为酵母菌发酵糖蜜产麦角甾醇的产业化应用奠定了基础。Ergosterol is an economically important metabolite produced by yeast. To improve the production of ergosterol by Saccharomyces cerevisiae YEH56 （pHXA42） from molasses, a cheap and regenerative material, different strategies were applied. First, Plackett-Burman design and central composite design were applied to screen the significant factors in fermentation medium using ergosterol yield （g/L） as the response value. Ergosterol yield reached 371.56 mg/L by using the optimal fermentation medium in shake-flask culture （total sugar in molasses 40 g/L, KH2PO4 1 g/L, K2HPO4 1.86 g/L, CuSOa.5H20 17.5 mg/L, FeSO4＂7H20 13.9 mg/L, MgSOa＇5H20 12.3 rag/L, corn steep liquor 10 mL/L）, which was increased by 29.5% compared with the initial culture. Second, ergosterol yield was increased by 62.1% using a pH-control strategy in a 5-L bioreactor. Third, ergosterol production was improved further by using molasses feeding strategy. After 38 h fermentation, ergosterol yield reached 1 953.85 rag/L, which was 3.2 times of that in batch fermentation. Meanwhile,ergosterol production rate was increased by 42.7% compared with that in the batch culture.

关 键 词：酿酒酵母 糖蜜 麦角甾醇 响应面分析法 底物流加补料 

分 类 号：TS249.3[轻工技术与工程—制糖工程]