选育耐受复合抑制剂酿酒酵母提高乙醇产量

Accelerated Ethanol Production by a Tolerant Saccharomyces cerevisiae to Inhibitor Mixture of Furfural,Acetic Acid and Phenol

能够耐受纤维素预处理中抑制剂的酿酒酵母对高效、经济生产纤维素乙醇至关重要。利用诱变结合驯化工程选育了一株可耐受复合抑制剂(1.3g/L糠醛、5.3g/L乙酸及1.0g/L苯酚)的工业酿酒酵母YYJ003。在p H 4.0的含有抑制剂的培养基中,耐受菌株乙醇产率是原始菌株的7.8倍,糠醛转化速率提高了5倍。在p H 5.5的复合抑制剂条件下,YYJ003发酵时间(16h)比野生菌株发酵时间(22h)缩短6h。在p H 4.0的未脱毒的玉米秸秆水热法预处理水解液中YYJ003的乙醇产率达到0.50g/g(乙醇/葡萄糖),乙醇产速达到4.16g/(L·h),而对照菌株无乙醇产出。

Construction of tolerant yeast to the inhibitory compounds from the pretreatment of lignocelluloses is quite required for efficient and economical cellulosic ethanol production. An industrial Saccharomyces cerevisiae strain YYJ003 was developed to be tolerant to mixed inhibitors,including 1. 3g / L furfural,5. 3g / L acetic acid and 1. 0g / L phenol. Compared with parent strain S,YYJ003 strain exhibited 7. 8-fold ethanol productivity and a6-fold conversion rate of furfural in the presence of inhibitor cocktail at p H 4. 0. At p H 5. 5 with inhibitor cocktails,the fermentation time for strain YYJ003 was shortened to 16 hours while 22 hours for S strain,respectively. Furthermore,YYJ003 achieved the ethanol yield of 0. 50 g / g glucose,and ethanol productivity of4. 16 g /（ L·h） in liquid hot water pretreated corn stover hydrolysate without detoxification at p H 4. 0 while strain S failed to ferment.