本研究以玉米秸秆水解液为原料,通过萃取发酵技术生产燃料丁醇,以提高丁醇产量,降低生产成本。通过对萃取剂的筛选与条件优化,确定纤维丁醇发酵的萃取剂为油醇,添加时间为发酵0 h,添加比例为1:1 (V/V)。该条件下发酵32 g/L糖浓度的玉米秸秆水解液,丁醇和总溶剂产量分别为3.28 g/L和4.72 g/L,比对照分别提高958.1%和742.9%。以D301树脂脱毒后5%总糖浓度的玉米秸秆水解液进行丁醇萃取发酵,丁醇和总溶剂产量分别达到10.34 g/L和14.72 g/L,发酵得率为0.31 g/g,与混合糖发酵结果相当。研究结果表明萃取发酵技术能够显著提高原料的利用率和丁醇产量,为纤维丁醇工业化生产提供了技术支撑。
Butanol production from corn stover hydrolysates (CSH) with in-situ liquid-liquid extraction was studied to enhance the production and reduce the fermentation cost. Oleyl alcohol was selected as the suitable solvent and added at the initial fermentation time with the ratio of 1:1 (oleyl alcohol: fermentation broth, V/V). Under this condition, butanol and ABE from CSH with 32.1 g/L total sugars were 3.28 and 4.72 g/L, which were 958.1% and 742.9% higher than those of the controls, respectively. Butanol and ABE production from CSH of 49.7 g/L total sugars after detoxification by ion exchange resin D301 coupled with extraction fermentation were 10.34 g/L and 14.72 g/L with an ABE yield of 0.31 g/g (g ABE/g utilized sugar), which were equal to those of glucose and xylose mixture fermentation. The detoxification and extraction fermentation technology of cellulosic butanol production would provide a crucial technical support to the industrialized production of cellulosic butanol.