甘蔗渣的酸催化常压甘油有机溶剂预处理及其酶解

预处理可以打破木质纤维素原料纤维素、半纤维素和木质素三大组分间的顽抗结构，从而提升纤维素基质可酶解性。本文针对目前常压甘油有机溶剂预处理花费时间过长的问题，尝试开展酸催化的常压甘油有机溶剂预处理研究以缩短预处理时间。实验通过单因素选择和响应面Box-Behnken设计优化，获得酸催化常压甘油有机溶剂预处理的最佳条件为：预处理温度245℃，预处理时间38min，硫酸添加质量0.1%。在此条件下获得基质48h酶解率的响应面预测值为94.0%，实际值为91.4%。结果表明响应面优化方案和回归模型适用于本实验，预处理显著提高了基质可酶解性。高浓度基质（15%～20%）酶解进一步证明了预处理后基质具有突出的可酶解性，20%浓度基质在酶载量5FPU/g干基质条件下批次酶解72h，酶解率达60%，葡萄糖浓度达83.4g/L。酸催化常压甘油有机溶剂酸预处理在明显缩短预处理时间的同时，能显著提高木质纤维素基质可酶解性，使后续工业化意义的浓醪酶解糖化成为可能。

Acid-catalyzed atmospheric glycerol organosolv pretreatment of sugarcane bagasse and its enzymatic hydrolysis

Pretreatment tends to disrupt the recalcitrant structure of lignocellulosic biomass consisting predominantly of cellulose, hemicellulose and lignin, thereby improving the enzymatic hydrolyzability of the substrate. To avoid too long pretreatment time during the current atmospheric glycerol organosolv pretreatment process, acid was taken as catalyst in the pretreatment process to shorten the pretreatment time. The acid-catalyzed atmospheric glycerol organosolv (ac-AGO) pretreatment was optimized by single factor selection and response surface Box-Behnken design optimization as below:pretreatment temperature 245℃, pretreatment time 38min, sulfuric acid addition 0.1% (mass yatio). Under optimized condition, the prediction value of 48h enzymatic hydrolysis yield was 94.0%, and the practical value was 91.4%. Results showed that the response surface optimization scheme and regression model was fit. The ac-AGO pretreatment significantly improved the substrate hydrolyzability. Enzymatic hydrolysis of substrate at high solid concentration (15%—20%) underlined the outstanding enzymatic hydrolysability of substrate, with 72h enzymatic hydrolysis yield being 60% and glucose titer being 83.4g/L at 20% of solid content and 5FPU/g dry substrate of the enzyme loading. The ac-AGO pretreatment can significantly improve the enzymatic hydrolysis of lignocellulose substrate, making it possible to afford downstream ethanol fermentation industry with high-titer fermentable sugars.