作　　者： ; ; ; ; ;

机构地区： 山东省环境保护科学研究设计院

出　　处： 《造纸科学与技术》 2013年第2期13-17,72,共6页

摘　　要： 木质纤维素原料生产燃料乙醇的主要步骤包括:预处理,纤维素酶解成可发酵糖,乙醇发酵,酒精提取,其中预处理是关键的一个步骤。普遍认为预处理后物料中大量木质素的存在会在纤维素酶解阶段对纤维素酶产生吸附作用,降低纤维素酶的作用效率。本文从预处理前后的玉米秸秆中提取了磨木木素。预处理前后的玉米秸秆中提取的磨木木素在化学性质上有很大的差异,预处理后磨木木素的分子量从约28000增加到约88000,但分子量的分散度降低。磨木木素中的β-β’结构和脂肪族中的–OH、C=O结构有所增加,木质素中亚结构β-1,β-5,β-O-4,5-5’,G-型等结构在稀酸预处理过程中得到了不同程度的降解。从吸附时间内蛋白变化的SDS-PAGE图中可见,木素对纤维素酶的吸附是随着时间逐渐增加的。说明预处理对木素对纤维素酶的吸附有很大的影响。从预处理后秸秆中提取的磨木木素要比从预处理前秸秆中提取的磨木木素多吸附15%的酶蛋白。 The process of bioethanol production contains four main steps ： pretreatment, enzyme hydrolysis of cellu- lose, fermentation, ethanol distillation. The most important step is pretreatment of lignocellulosic materials. During dilute acidic pretreatment process, very little lignin can be moved out. It is not good for the enzyme hydrolysis process as the existence of lignin can adsorb cellulase to deactivate it. Milled wood lignins （MWL） were extracted from corn stover before and after diluted acid pretreatment. There were a lot of differences in chemical features be- tween the MWLs. The molecular weight of MWL was increased from about 28000 to about 88000 after diluted acid pretreatment. From the results of NMR analysis, it was concluded that, after pretreatment, the sub-structure of β-β＇, C=O and aliphatic - OH was increased, while β-1, β-5, β-O-4, 5-5＇, G was decreased. From the SDS - PAGE results of cellulase changes, we can conclude that cellulase adsorption to milled wood lignin was increased with time and the milled wood lignin from corn stover after diluted acid pretreatment can absorb more protein than the milled wood lignin from corn stover before diluted acid pretreatment. According to the protein con- centration changes, it showes that diluted acid pretreatment has a great impact on cellulase adsorption to lignin. The milled wood lignin from corn stover after diluted acid pretreatment can absorb 15% more protein than the milled wood lignin from corn stover before diluted acid pretreatment.

关 键 词： 磨木木素 分子量 木质素亚结构 吸附 纤维素酶

领　　域： [动力工程及工程热物理]