果胶对多酚氧化酶活性及热稳定性的影响  

Effects of Pectin on the Activity and Thermal Stability of Polyphenoloxidase

作　　者：廖滔 周磊[1,2] 刘军平 邹立强[1] 刘成梅[1] 刘伟[1,3] Liao Tao;Zhou Lei;Liu Junping;Zou Liqiang;Liu Chengmei;Liu Wei(State Key Laboratory of Food Science and Technology,Nanchang University,Nanchang 330047;School of Life Sciences,Nanchang University,Nanchang 330031;National R&D Center for Freshwater Fish Processing,Jiangxi Normal University,Nanchang 330022)

机构地区：[1]南昌大学食品科学与技术国家重点实验室,南昌330047 [2]南昌大学生命科学学院,南昌330031 [3]江西师范大学国家淡水鱼加工技术研发专业中心,南昌330022

出　　处：《中国食品学报》2021年第5期67-74,共8页Journal of Chinese Institute Of Food Science and Technology

基　　金：中国博士后科学基金项目(2019M652288);国家自然科学基金项目(31860452);江西省青年科学基金项目(20181BAB214019)。

摘　　要：本文分别利用紫外分光光度计和荧光分光光度计探究0~20 mg/mL果胶对PPO酶促反应活性、热钝化动力学、热失活构象变化及抑制剂作用的影响。结果表明:PPO活性随果胶质量浓度的上升而下降,当果胶质量浓度为20 mg/mL时,PPO活性下降约20%;热钝化动力学显示,果胶能显著提高PPO的热稳定性;热处理使PPO三级结构发生明显改变,而果胶能增强PPO在热钝化下构象的稳定;有机酸对PPO活性的抑制作用因果胶的加入而有1.5%~25.7%的增强。本研究结果为果蔬制品酶促褐变的控制提供理论参考。In this paper,the effects of 0-20 mg/mL pectin on polyphenoloxidase(PPO)enzymatic activity,thermal passivation kinetics,thermal passivation conformational changes and inhibitor action were investigated by ultraviolet spectrophotometer and fluorescence spectrophotometer,respectively.The results showed that PPO activity decreased with the increase of pectin mass concentration.When pectin mass concentration was 20 mg/mL,PPO activity decreased nearly 20%.The thermal passivation kinetics showed that pectin could significantly improve the thermal stability of PPO.Thermal treatment significantly changed the tertiary structure of PPO,while pectin could enhance the conformational stability of PPO under thermal passivation.The inhibitory effect of organic acids on PPO activity was increased by 1.5%-25.7%with the addition of pectin.The results of this study provide theoretical reference for the control of enzymatic browning of fruit and vegetable products.

关 键 词：多酚氧化酶 果胶 活性 热钝化动力学 稳定性 

分 类 号：TS255.1[轻工技术与工程—农产品加工及贮藏工程]