纤维素在离子液体-水介质中酶解的研究

Enzymatic hydrolysis of cellulose in aqueous ionic liquid solution

在20%1-乙基-3-甲基咪唑醋酸盐离子液体([Emim]Ac)和水的混合溶液中,用纤维素酶和纤维二糖酶协同降解纤维素生产葡萄糖和其它还原糖,检验了2种酶的酶活比对纤维素降解的影响以及离子液体对2种酶的酶活的影响.结果表明,在适当的酶活比(如0.19)下,纤维素酶和纤维二糖酶可以有效协同纤维素的酶解,并显著提高葡萄糖(35.2%,72 h)和还原糖的产率(86.5%,72 h).葡萄糖和还原糖的生产在72 h后仍然持续增加.纤维素酶和纤维二糖酶的活性在[Emim]Ac中都会受到不同程度的影响.纤维二糖酶的酶活在反应初始的3 h陡降66.5%,但是随后会显示出在低酶活水平上的稳定性.

Cellulose was enzymatically hydrolyzed to glucose and reducing sugars in 20% 1-ethyl-3-methylimidazolium acetate( [Emim]Ac)-aqueous solution.Cellulase and cellobiase were both used to catalyze cellulose hydrolysis,and the influence of activity ratio between these two enzymes on cellulose degradation and the influence of ionic liquid on the activities of enzymes were studied.The results indicated a synergetic catalysis on cellulose hydrolysis by cellulase and cellobiase at a proper enzymatic activity ratio such as 0.19,which significantly improved the yield of glucose( 35.2% at 72 h) and reducing sugars( 86.5% at 72 h).The production of glucose and reducing sugars was still increasing after 72 h reaction.The activities of cellulase and cellobiase were affected by[Emim]Ac with different degrees. The activity of cellobiase dropped by 66.5% at the first 3 h,but remained fairly constant at relatively low activity in the subsequent time period.