木质素对蔗渣酶水解的影响

采用机械活化方法对蔗渣进行处理，研究在原料可及性变化时木质素对蔗渣酶解的影响，用牛血清蛋白（BSA）预先使原料中木质素吸附饱和的方法来测定木质素对酶的吸附情况、用X-射线衍射和扫描电镜来测定蔗渣结晶结构、表面形态来表征原料可及性，从而分析影响的可能机制。结果表明木质素对蔗渣酶水解的影响与蔗渣可及性有关，原料可及性越高，影响越小。当蔗渣可及性相对较低时，此时木质素影响蔗渣酶水解转化率的两种方式（木质素与纤维素、半纤维素组成的致密结构限制纤维素对酶的可及性及木质素对纤维素酶的无效吸附作用）同时存在。当原料的可及性增加到一定程度后（如机械活化2h的蔗渣），木质素对纤维素酶的吸附作用几乎消除，木质素对蔗渣酶水解的影响主要表现为对酶的可及性的限制。

The effect of lignin in bagasse enzyme hydrolysis

The mechanical activation method was employed to process bagasse. The effect of lignin on enzymatic hydrolysis was studied effect when the raw material accessibility changed. The X-ray diffraction and scanning electron microscopy(SEM)were used to determine the crystal structure and surface morphology of bagasse,to characterize the raw material accessibility,and analyze the influence of the possible mechanisms. The results showed that the effect of lignin on bagasse enzyme hydrolysis was related to bagasse accessibility. The higher raw material availability was,the smaller the effect was. When the accessibility of bagasse was relatively low,lignin affected the rate of enzymatic hydrolysis of bagasse in two ways (limiting cellulose accessibility and unproductive binding of the enzymes) simultaneously. When the availability of raw material increased to a certain level (for example,2 hours by mechanical activation of bagasse) and lignin adsorption of cellulose was virtually eliminated. The main effect of Lignin on bagasse enzymatic hydrolysis was limiting enzyme accessibility.