树干毕赤酵母对玉米秸秆蒸汽爆破水解液及其蒸馏釜底液中木糖的发酵  

Fermentation of Steam-exploded Corn Stover Hydrolysate and ItsDistillation Residue by Pichia stipitis

作　　者：赵晨[1] 方浩[1] 孔端男[1] 朱均均[1] 余世袁[1] 

机构地区：[1]南京林业大学林木遗传与生物技术省部共建教育部重点实验室,江苏南京210037

出　　处：《林产化学与工业》2013年第4期37-42,共6页Chemistry and Industry of Forest Products

基　　金：国家林业局林业公益性行业科研专项(201004001);国家自然科学基金资助项目(31100432);江苏省自然科学基金资助项目(BK2011819)

摘　　要：为了能够高效地利用木质纤维素水解液中的糖,采取了一种新的工艺路线:玉米秸秆水解液中的葡萄糖先被酿酒酵母转化为乙醇,并通过蒸馏将发酵液中的乙醇去除,然后再用驯化过的树干毕赤酵母将蒸馏釜底液中的木糖转化为乙醇。结果表明,蒸馏后的水解液中84.4 g/L木糖经过48 h发酵的乙醇得率和木糖利用率分别为80.4%和89.7%;高浓度抑制物的蒸馏釜底液中木糖的利用可以通过提高初始pH值的方法加以改善。初始pH值为5.5,蒸馏釜底液中乙酸为3.2 g/L时木糖利用率和乙醇得率分别为91.0%和76.3%(以木糖计)。由此充分表明,通过这种工艺路线酿酒酵母发酵液中的木糖可以被有效利用,从而较为经济地解决了木质纤维素制备燃料乙醇过程中木糖的利用问题。In order to utilize sugars in lignocellulosic hydrolysate efficiently, a novel technology was applied in present study. The glucose in the corn stover hydrolysate was converted to ethanol by Saccharomyces cerevisiae and the ethanol in the fermentation broth was removed by distillation. Then the xylose in the distillation residue was fermented to produce ethanol by an adapted Pichia stipitis. The results showed that the ethanol yield and xylose consumption ratio of 84.4 g/L xylose fermentation in the dis- tilled hydrolysate were 80.4% and 89.7%, respectively, after 48 h fermentation. The utilization of xylose in distillation residue with higher inhibitor concentration could be improved by higher initial pH. The ethanol yield and xylose consumption ratio were 80.2% （76.3%） and 94.8% （91.0%） , respectively, when the initial pH was 5.5 and the acetic acid in the distillation resi- due was 3.2 g/L. This fully indiacted that xylose in S. cerevisiae culture broth can be effectively utilized by adapted P. stipitis by using this novel technological route. This novel method solved the problem of xylose utilization efficaciously in the process of etha- nol production from lignocellulosic materials.

关 键 词：树干毕赤酵母 木质纤维素水解液 乙醇 发酵抑制物 乙酸 

分 类 号：TQ351[化学工程] TQ92[轻工技术与工程—发酵工程]