枯草芽孢杆菌利用玉米秸秆水解液生产乙偶姻

Production of acetoin from corn stover hydrolysate by Bacillus subtilis

玉米秸秆作为可再生农林业资源,其富含木质纤维素,被酸水解后可产生木糖、葡萄糖、阿拉伯糖等糖类,可作为碳源用于枯草芽孢杆菌发酵生产乙偶姻,在开发新能源和环境保护等方面具有重要的经济效益和社会效益。通过响应面设计研究了水解酸浓度、水解温度、水解时间对玉米秸秆水解液中糖类物质得率的影响,得到最优的预处理条件为:温度120℃,硫酸体积分数1.0%,水解时间1 h,在得到较多糖类物质的前提下减少了对玉米秸秆纤维结构的破坏,以枯草芽孢杆菌利用混合玉米秸秆水解液和LB培养基在5^(th) L自动发酵罐发酵至第5天,乙偶姻产量达到最大值10.4 g/L,其水解残渣可用于造纸,协同提高玉米秸秆的综合利用率。

As a renewable agroforestry resource,corn stover is rich in lignocellulose,which can produce xylose,glucose,arabinose and other sugars after being hydrolyzed by acid.These sugars can be used as a carbon source for the fermentation of Bacillus subtilis to produce acetoin,which has important economic and social benefits in the development of new energy and environmental protection.The effects of hydrolysis acid concentration,hydrolysis temperature and hydrolysis time on the yield of sugars in corn stover hydrolysate were investigated by response surface design,and the optimal pretreatment conditions were 120℃,sulfuric acid concentration of 1.0%and hydrolysis time of 1 h,under which the damage to the fiber structure of corn stover was reduced while obtaining more sugars.The yield of acetoin reached the maximum of 10.4 g/L until the 5^(th)day by the fermentation of B.subtilis in the 5 L automatic fermenter with the mixture of hydrolyzate of corn stover and LB medium.And the hydrolyzate residue could be used in papermaking,synergistically improving the comprehensive utilization of corn stover.