氢氧化钙预处理对3种秸秆酶解糖化效率的影响

摘要

Corn straw,rice straw and wheat straw were chosen as the substrates,and the effect of lime pretreatment time and temperature were comparatively examined by determination of the enzymatic transformation ratio.Results showed the yield of reducing sugar of wheat straw and rice straw could reach 60.38% and 46.77% respectively after lime pretreatment of 2 h at the temperature of 90 ℃.In contrast,corn straw needed more higher pretreated temperature of 121 ℃ for 1 h,whose yield of reducing sugar reached 56.82%.Wheat straw was more suitable for the pretreatment using lime.Further microstructural analysis of the straw samples was investigated by infrared spectrum,results showed that lime pretreatment could significantly degrade lignin in wheat straw.The selective degradation of lignin promoted the destruction of the spatial structure barrier of lignocellulosic macromolecules,retained more cellulose for later enzymatic saccharification, and improved straw enzymatic saccharification efficiency.%选取玉米秸秆、稻草秸秆和小麦秸秆为原料,研究不同氢氧化钙预处理条件对3种秸秆酶解糖化效率的影响.结果表明,小麦秸秆和稻草秸杆的最高还原糖转化率分别为60.38%和46.77%(90 ℃条件下预处理2 h),玉米秸秆达到最高还原糖转化率(56.82%)则需进一步提高预处理温度(121 ℃条件下预处理1 h),3种秸秆中小麦秸秆较适合使用氢氧化钙预处理方式.对预处理秸秆木质纤维素各成分与红外微观结构分析表明,氢氧化钙预处理能显著降解小麦秸秆中的木质素,木质素选择性降解促进了木质纤维素大分子空间结构屏障的破坏,保留了更多纤维素以供后期酶解糖化利用,进而提升了秸秆酶解糖化效率.