红枣多酚氧化酶酶学特性及其钝化动力学研究  

Study on the Polyphenoloxidase (PPO) Characteristics and Deactivation Kinetics Extracted from Chinese Date

作　　者：宋丽军[1,2] 张丽[1,2] 侯旭杰[1,2] 李述刚[1,2] 

机构地区：[1]塔里木大学生命科学学院,新疆阿拉尔843300 [2]南疆特色农产品深加工兵团重点实验室,新疆阿拉尔843300

出　　处：《塔里木大学学报》2013年第3期1-8,共8页Journal of Tarim University

基　　金：塔里木大学校长基金项目(TDZKSSZD201101);新疆生产建设兵团项目(2010GG61);新疆生产建设兵团优秀青年创新资金专项(2010JC32)

摘　　要：本实验以新疆骏枣为原料，邻苯二酚为底物，采用分光光度法研究了红枣中多酚氧化酶（PPO）的酶学特性。结果表明：红枣PPO最适温度为45℃，最适pH值为6．8-7．2，最适底物浓度为0．402mol／L；最大反应速度Vmax=7．164U／min，Km=0．6714mM；当温度大于55℃时，热处理对PPO的钝化效果比较显著，80℃处理20min即可完全钝化红枣PPO；热处理对红枣PPO的钝化符合一级反应动力学，其ZT：32．78℃，Ea=29．658KJ／mol。In this paper, the enzymatic characteristics of polyphenoloxidase in Chinese date was studied by spectrophotometric method, using Xinjiang Jun Jujube as raw material, and pyrocatechol as substrate. The results showed that, for the PPO of Jun Jujube, the optimal temperature of the was 45 ℃, the optimal pH was 6.8 - 7.2 and the optimal concentration of substrate was 0.402 mol/L, the maximum velocity of PPO in Jun Jujube was 7. 164 U/min and Km was 0.6714 mM, the passivation effect was significant when the temperature is over 55℃ ,and the PPO was completely passivated treated 20 min at 80 %. The passivation of PPO by heat treatment fitted the first - order kinetics, the ZT was 32.78 ℃ and the Ea was 29. 658 K J/mol.

关 键 词：红枣 多酚氧化酶 酶学特性 抑制动力学 

分 类 号：TS201.5[轻工技术与工程—食品科学]