库尔勒梨多酚氧化酶的酶学特性  

Enzymatic Properties of Polyphenol Oxidase from Kuerle Pear

作　　者：朱路英[1] 吴伟伟[1,2] 孙杰[1] 都婷婷[1] 

机构地区：[1]鲁东大学生命科学学院,山东烟台264025 [2]河北农业大学动物科技学院,河北保定071001

出　　处：《食品科学》2010年第21期275-278,共4页Food Science

基　　金：鲁东大学校基金项目(LY20063307);鲁东大学学科建设经费资助项目

摘　　要：以邻苯二酚为底物,采用分光光度法对库尔勒梨多酚氧化酶(PPO)的酶学特性进行研究。结果表明:库尔勒梨PPO的最适pH值为5.7,最适温度为42℃;短时间高温能显著抑制PPO酶活力;PPO催化的酶促褐变反应符合米氏动力学方程,该酶促反应的最大速率为169.49U/min,Km值为0.152mol/L;与柠檬酸、NaCl和EDTA-2Na相比,抗坏血酸对库尔勒梨PPO的抑制效果较好。Enzymological characterization of the polyphenol oxidase（PPO） from Kuerle pear towards catechol as a substrate was conducted using spectrophotometry method.The results showed that the optimal pH and temperature for this enzyme was 5.7 and 42 ℃.High temperature treatment could inhibit PPO activity.The kinetics of PPO reaction was in accord with the Michaelis-Menten equation,with Km and Vmax values of 0.152 mol/L and 169.49 U/min,respectively.Ascorbic acid exhibited stronger inhibition effect on PPO activity than citric acid,NaCl and EDTA-2Na.

关 键 词：库尔勒梨 多酚氧化酶 酶学特性 抑制效应 

分 类 号：Q554.1[生物学—生物化学]