超声波对多酚氧化酶酶活力的影响及其机理  

Effect and Mechanisms of Ultrasonic Treatment on Polyphenol Oxidase Activity

作　　者：王文宗[1] 李琳[1] 林鸿佳[1] 陈玲[1] 李冰[1] 

机构地区：[1]华南理工大学轻工与食品学院,广东广州510640

出　　处：《食品科学》2010年第17期331-334,共4页Food Science

基　　金：国家"863"计划重点项目(2007AA100405);广东省教育厅产学研基地科技成果转化重大项目(cgzhzd0704);科技部国际科技合作计划项目(2009DFA32070)

摘　　要：以多酚氧化酶(PPO)为对象,研究不同超声波条件对PPO酶活力的影响及其机理。结果表明:PPO酶活力随着超声时间增加而降低,随着超声波功率增大先略增大然后逐渐降低;在超声波作用下PPO的稳定温度和pH值分别为40℃和6.8;经超声波处理后的PPO,其动力学参数米氏常数Km增大、最大反应速率Vmax减小;PPO二级结构中β-转角相对减少。The effects of different ultrasonic treatment conditions on polyphenol oxidase （PPO） activity were investigated.Meanwhile,related mechanisms were explored.The results indicated that with prolonged ultrasonic treatment time,PPO activity initially increased,followed by a decrease.Higher ultrasonic power resulted in a slight increase followed by a gradual decrease.The stable temperature and pH for PPO treated by ultrasonic were respectively 40 ℃ and 6.8,respectively.After ultrasonic treatment,an increase in the Km of PPO and a decrease in its Vmax were simultaneously observed,and the content of β-turn secondary structures decreased.

关 键 词：PPO 超声波 酶活力 

分 类 号：TS255.44[轻工技术与工程—农产品加工及贮藏工程]