添加外源物对蒸汽爆破玉米秸秆酶水解性能的影响

Effect of exogenous additives on enzymatic hydrolysis of steam exploded corn stover

研究了8种添加物辅助单、双酶水解蒸汽爆破玉米秸秆的效果和规律。结果表明,在8种外源物中,添加Tween-80对β-葡萄糖苷酶和纤维素酶水解的促进作用最佳,可显著提高酶水解得率和酶活的稳定性。在底物纤维素质量浓度为50 g/L、纤维素酶用量为15.0μmol/(min.g)、β-葡萄糖苷酶用量为30.0μmol/(min.g)的条件下,添加4.0 g/L Tween-80反应48 h,纤维素水解生成葡萄糖和总还原糖的酶解得率分别达到86.85%和93.45%,较空白对照分别提高了7.34%和9.59%,其中可发酵性葡萄糖占总还原糖的92.94%。进一步考察该酶解条件下的蛋白质和酶活回收率,结果表明:添加Tween-80后可溶性总蛋白质的回收率提高了56.83%,β-葡萄糖苷酶和纤维素酶酶活回收率分别提高了16.87%和40.04%。

The hydrolysis effects and disciplination of steam exploded corn stover catalyzed by cellulose and/or β-glucosidase assisted with exogenous additives were investigated in this paper.Test results showed that Tween-80 was the best exogenous additive for its excellent improvement on the enzymatic hydrolysis yield and enzymes stability.At the Tween-80 loading of 4.0 g/L,the glucose yield and total reduced sugar yield reached 86.85 % and 93.45 % with improved by 7.34 % and 9.59 % compared with the control respectively as steam exploded corn stover was hydrolyzed for 48 h with 15.0 μmol/（min·g） cellualse and 30.0 μmol/（min·g） β-glucosidase,and in this hydrolysate the fermentable glucose accounted to 92.94 % of the total reduced sugar.Under this reaction conditions,56.83 % of the soluble enzymatic protein,16.87 % of the β-glucosidase activity and 40.04 % of the cellulase activity could be recovered from the enzymatic hydrolysate of steam exploded corn stover as Tween-80 additives was used.