摘要
以邻苯二酚（C6H6O2）为底物，采用分光光度法在波长398nm下测定鸡腿菇Coprinus comaus多酚氧化酶（PPO）活性，分析其pH值、温度及底物浓度等因素对PPO活性的影响。结果表明，鸡腿菇PPO活性的最适pH值4.0～5．0，最适温度20℃，在沸水浴30s后酶基本被钝化。鸡腿菇酶促褐变反应的动力学符合米氏方程，米氏常数k为0.64mol·L^-1，最大反应速度vmax为0.08U·min^-1。对鸡腿菇不同部位的PPO活性分析表明，菌盖PPO活性〉菌柄（上）〉菌柄（下）。
Polyphenol oxidase （PPO） activities of Coprinus comaus were spectrophotometrically determined at 398nm with catechol as substrate in different pH,temperatures and substrate concentrations and so on. The results showed that the optimal pH and temperature of PPO activity were pH 4. 0 - 5.0 and 20℃respectively, and the PPO was inactivated at 100℃ for 30s. The reaction kinetics of enzymatic browning was accordant with Michaelis-Menten,the Km and vmax were 0.64mol·L^-1 and 0. 08U ·min^-1 respectively. This paper also studied the difference of PPO activity in different parts of Coprinus comaus, the results showed that the PPO activity of pileus 〉 the stipe （top） 〉 the stipe （below）.
出处
《山地农业生物学报》
2007年第1期43-47,共5页
Journal of Mountain Agriculture and Biology
基金
福建省产学研联合开发基金资助项目[闽财指(2003)462]
关键词
鸡腿菇
多酚氧化酶
动力学特性
温度影响
Coprinus comaus
polypbenol oxidase
reaction kinetic characteristics
temperature affect
