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，〖JP2〗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15.0 μmol/(min〖DK〗·g)、〖JP〗β-葡萄糖苷酶用量为30.0 μmol/(min〖DK〗·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 %。
Abstract
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〖DK〗·g) cellualse and 30.0 μmol/(min〖DK〗·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.
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基金
收稿日期：2011-07-04修回日期：2011-09-16基金项目：国家林业局林业公益性行业科研专项项目（201004001）；江苏省高校科技创新团队资助项目；国家自然科学基金项目（31070523,31070513）；江苏省高校自然科学重大基础研究项目（10KJA22019，200904017）〖ZK）〗作者简介：陈牧（1974—），实验师。Email：chenmu-74@hotmail.com。
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