荞麦淀粉的真菌淀粉酶酶解动力学研究  

Kinetics of buckwheat starch enzymatic hydrolysis with fungal-α-amylase

作　　者：张国权[1] 史一一[1] 魏益民[1] 欧阳韶晖[1] 

机构地区：[1]西北农林科技大学食品科学与工程学院,杨凌712100

出　　处：《农业工程学报》2007年第5期42-46,共5页Transactions of the Chinese Society of Agricultural Engineering

基　　金：西北农林科技大学校重点科研项目(20030203085)

摘　　要：为掌握真菌α-淀粉酶对荞麦淀粉的酶解特性，该文研究了不同底物浓度、酶浓度、pH值及温度对水解反应速率的影响，运用米氏方程对水解动力学过程进行描述和拟合，用Lineweaver—Burk和Wilkinson统计法求解动力学参数。结果表明，真菌α-淀粉酶对荞麦淀粉的水解反应初期遵循一级反应规律，可用米氏方程对水解动力学过程进行描述和拟合，在酶浓度为0．5U／mL、pH值5．5、温度为55℃时米氏常数Km为5．470mg／mL，最大反应速率Vm为1．587mg／（mL·min）。确立的包括底物浓度、酶浓度、水解温度在内的荞麦淀粉酶水解动力学模型，在303．15～333．15K的温度范围内适用。In order to master the enzymatic hydrolysis characteristics of buckwheat starch by fungal-α-amylase, the effects of substrate concentration, enzymatic concentration, pH value and temperature on reaction velocity were determined. The kinetics of the hydroly- sis reaction were described with the Michaelis-Menten equation, and the kinetic parameters were calculated by the Lineweaver-Burk and Wilkinson methods. The results show that buckwheat starch hydrolysis by fungal-α-amylase obeys the classical first-order reaction rate, and the kinetics can be modeled by Michaelis-Menten equation. In the condition of 55℃ and pH 5.5, the Minchaeli constant （Km） and maximum rate（Vm） for 0.5 U/mL of fungal-α-amylase are 5.470 mg/mL and 1. 587 mg/（mL · min）. The kinetic model, including the parameters such as substrate concentration, enzymatic concentration and temperature, is suit for the hydrolysis under the temperature range from 303.15 K to 333.15 K.

关 键 词：荞麦淀粉 真菌Α-淀粉酶 酶解 动力学 

分 类 号：TS201.25[轻工技术与工程—食品科学]