【摘要】 为了降低木质纤维素水解液发酵抑制剂对乙醇发酵的负影响,采用混合菌种对木质纤维素稀酸水解液乙醇发酵方式进行了研究。对批式发酵、补料批式发酵和间隔补料批式发酵3种发酵方式进行了比较。实验结果表明,间隔补料批式发酵可以有效地减弱水解液中抑制因子对菌种的影响,乙醇产量明显高于其他两种发酵方式,利用酿酒酵母(Saccaromyces cerevisiae 2.535)和嗜鞣管囊酵母(Pachysolen tannophilis ATCC 32728)混合发酵,乙醇产量最终达到14.4g/L,乙醇产率(Yp/s)为0.47g/g,相当于最大理论产率的92.2%。利用酿酒酵母和重组大肠杆菌混合菌种发酵,乙醇产量达到了14.5g/L。对木质纤维素稀酸水解液采用间隔补料批式乙醇发酵方法,可进一步减少抑制剂对乙醇发酵的影响,使发酵顺利进行。更多还原

【Abstract】 In order to reduce negative effect of inhibitory compounds in bioconversion process of diluted-acid hydrolysis of lignocellulose to ethanol the fermentations were carried out with cocultures and batch,fed-batch and intermittent fed-batch fermentation methods.By the intermittent fed-batch fermentation,fermenting with coculture Saccaromyces cerevisiae 2.535 and Pachysolen tannophilis ATCC 32728,the ethanol concentration was 14.4g/L,and the ethanol yield(Yp/s)was 0.47g ethanol/g sugar,corresponding to 92.2% of theoretical ethanol yield.Fermenting with coculture Saccaromyces cerevisiae 2.535 and recombinant Escherichia coli,the ethanol concentration was 14.5g/L.The demonstration indicates that the new method results in higher ethanol yield than that of other two methods and reduces the impact inhibitory concentration effectively.更多还原