大麦发芽过程中多酚氧化酶酶学特性初步研究  

Study on the enzymatic characteristics of polyphenol oxidase in malting barley

作　　者：孙丽华[1] 李秀琳[1] 徐凯[1] 孙俊[1] 张天雪[1] 赵长新[1] 

机构地区：[1]大连工业大学生物与食品工程学院,辽宁大连116034

出　　处：《中国酿造》2008年第4期35-38,共4页China Brewing

基　　金：国产大麦指纹图谱库的建立(2004ln-fj-004)

摘　　要：通过研究反应速率与底物浓度之间的关系,确定大麦多酚氧化酶(PPO)的米氏常数Km为1.89×10-3mol/L。利用双因素全面性实验测定大麦PPO作用的最适条件,结果表明,80℃、pH8.4为大麦PPO最适作用条件。建立分光光度法测定大麦发芽过程中PPO活性变化的方法,最适测定条件为酶添加量<5mL,反应时间4min,检测波长450nm。PPO在沸水中处理9min即可有效抑制其活性。Through the relation between the reaction rate and the concentration of substrate, the determinate Michaelis constant Km of the polyphenol oxidase （PPO） of barley was 1.89 × 10^-3mol/L Utilizing the double factors general experiment to determine the optimal assay conditions and the optimal conditions are as followings： the temperature 80℃ and pH 8.4, the enzyme solution 5 ml, reaction for 4 min, 450 nm absorption wave length. In the boiling stabilization aspect, treating 9 min can effectively inhibit the activity of PPO. According to the results as before, the activity of PPO was determined during the germination of barley by spectrometry.

关 键 词：多酚氧化酶 大麦 米氏常数 

分 类 号：Q55[生物学—生物化学]