白毫早鲜叶茶多酚氧化酶酶学特性  

Features of Polyphenol Oxidase in Baihaozao Fresh Tea Leaves

作　　者：孙慕芳[1,2] 张洁[1,2] 郭桂义[1,2] 

机构地区：[1]信阳农林学院茶学系,河南省高校信阳毛尖茶产业工程技术研究中心,信阳市茶产业基础研究重点实验室,河南信阳464000 [2]安徽省大别山区农林特色产业协同创新中心,安徽合肥230061

出　　处：《贵州农业科学》2014年第6期140-143,共4页Guizhou Agricultural Sciences

基　　金：河南省教育厅科学技术研究重点项目资助计划"适制信阳红茶的品种筛选及品质改良研究"(14A210022);河南省科技攻关项目"茶园环保型专用肥及配套施肥技术的研究"(112102110142);信阳农林学院校级青年科学基金项目"信阳高抗寒性茶树种质资源的研究"

摘　　要：为了解白毫早鲜叶中的PPO酶学特性,采用分光光度法,研究底物浓度、温度和pH对白毫早鲜叶PPO活性的影响以及PPO的热稳定性。结果表明:PPO活性随着温度、pH的增大呈先增大后减少的钟形曲线关系,其最适温度为40℃,最适pH为6.0;其耐热性较强,于80℃处理1min可钝化酶活力。酶促反应在温度37℃、pH 5.6柠檬酸-磷酸缓冲液、邻苯二酚为底物条件下,Km值和Vmax分别为0.621 7mol/L和4.46U/min。In order to explore the enzymatic characteristics of PPO in Baihaozao fresh tea leaves, spectrophotometric method was employed to study the effects of substrate concentration,temperature and pH on PPO activity and its thermal stability.Results：PPO activity first increased and then decreased with temperature and pH increasing.The suitable temperature and pH was 40℃ and 6.0 respectively;The thermal stability was strong,and the enzyme activity could be passivated after treated at 80℃ for one minute.Values of Km and Vmax were respectively 0.6217 mol/L and 4.46 U/min under the following conditions：temperature 37℃,pH 5.6 and substrate of catechol.

关 键 词：白毫早 鲜叶 多酚氧化酶 特性 

分 类 号：S571.1[农业科学—茶叶生产加工]