壳聚糖酶解的随机进攻动力学模型

Random Attacking Model for Enzymatic Hydrolysis of Chitosan

在假设里氏木霉ATCC56764产生的壳聚糖酶水解壳聚糖是以唯一内切方式随机进攻 b -1,4糖苷键的基础上,结合终产物非竞争性抑制的M-M动力学,建立了壳聚糖降解的数学模型,并用四阶Runge-Kutta方法结合Powell优化方法对模型中各个动力学参数进行了优化。模型计算结果与实验数据的比较表明,建立的数学模型能够合理地描述和解释壳聚糖降解的动力学过程,有助于加深对壳聚糖酶法降解机理的认识,对生产特定聚合度的壳聚糖具有指导意义。

Assuming the degradation of polysaccharide chains of chitosan is solely caused by endochitosanase which will randomly cleavage the β-1, 4 glycosidic bond of chitosan, a mathematical model named Random Attacking Model for chitosan hydrolysis was proposed. The model is based on Michaelis-Menten kinetics considering noncompetitive inhibition by end product - D-glucosamine. The model parameters were correlated by a Powell optimization program from the experimental data of enzymatic hydrolysis of chitosan. The good agreement between the experimental data and the calculated results indicated that the model was capable to simulate the enzymatic hydrolysis of soluble chitosan by chitosanase from Trichoderma reesei ATCC56764 for various initial chitosan concentration and chitosanase activity.