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Bioresour Technol. 2013 Feb;130:757-62. doi: 10.1016/j.biortech.2012.12.122. Epub 2012 Dec 23.
A new model for enzymatic hydrolysis of lignocellulosic biomass distinguishes causal influences from enzyme deactivation and restrictions on the accessibility of cellulose. It focuses on calculating the amount of unreacted cellulose at cessation of enzyme activity, unlike existing models that were constructed for calculating the time dependence of conversion. There are three adjustable parameters: (1) 'occluded cellulose' is defined as cellulose that cannot be hydrolysed regardless of enzyme loading or incubation time, (2) a 'characteristic enzyme loading' is sufficient to hydrolyse half of the non-occluded cellulose, (3) a 'mechanism index' measures deviations from first-order kinetics. This model was used to predict that the optimal incubation temperature is lower for lignocellulosics than for pure cellulose. For steam-exploded pine wood after 96h incubation, occluded cellulose was 24% and 26% at 30°C and 50°C, and the characteristic enzyme loadings were 10 and 18FPU/g substrate, respectively.
一种用于木质纤维素生物质酶水解的新模型区分了因果影响、酶失活以及纤维素可及性限制。与现有的用于计算转化率时间依赖性的模型不同，它侧重于计算酶活性停止时未反应纤维素的量。有三个可调参数：（1）“封闭纤维素”定义为无论酶负载或孵育时间如何，都无法水解的纤维素，（2）“特征酶负载”足以水解一半的非封闭纤维素，（3）“机制指数”衡量偏离一级动力学的程度。该模型用于预测木质纤维素的最佳孵育温度低于纯纤维素。对于 96 小时孵育后的蒸汽爆破松木，30°C 和 50°C 时封闭纤维素分别为 24%和 26%，特征酶负载分别为 10 和 18FPU/g 底物。
