食品科学 ›› 2011, Vol. 32 ›› Issue (21): 86-90.doi: 10.7506/spkx1002-6630-201121018

• 基础研究 • 上一篇    下一篇

表没食子儿茶素没食子酸酯(EGCG)在超声场中热稳定性的动力学

许 楠1,卓 雅1,曹雁平1,2,*,肖俊松1,2,吴葛洋1   

  1. 1.北京工商大学食品学院 2.食品添加剂与配料北京市高校工程研究中心
  • 出版日期:2011-11-15 发布日期:2011-11-11
  • 基金资助:
    “十二五”国家科技支撑计划项目(2011BAD23B02)

Kinetic Modeling of the Thermal Stability of EGCG in an Ultrasonic Filed

XU Nan1,ZHUO Ya1,CAO Yan-ping1,2,*,XIAO Jun-song1,2,WU Ge-yang1   

  1. (1. School of Food and Chemical Engineering, Beijing Technology and Business University, Beijing 100048, China; 2. Beijing Higher Institution Engineering Research Center of Food Additives and Ingredients, Beijing 100048, China)
  • Online:2011-11-15 Published:2011-11-11

摘要: 研究弱酸环境下pH值对表没食子儿茶素没食子酸酯(epigallocatechin gallate,EGCG)的影响,以及在非超声场和0.25W/cm2、135kHz超声场中EGCG的稳定性,利用高效液相色谱对其进行定量分析。结果显示:温度为20℃、相同pH值时超声场中EGCG的稳定性均低于非超声场;pH6.2、超声40min时EGCG的损失率为10.70%,是非超声场的5.63倍。通过线性回归计算,确定EGCG在非超声场及超声场中的反应均符合一级反应动力学规律。超声场中,EGCG的反应速率常数为0.00228min-1,是非超声场的4.3倍;反应活化能为22861.13kJ/mol,比非超声场降低了14.0%;指前因子为28.30s-1,比非超声场提高了13.5%。

关键词: 表没食子儿茶素没食子酸酯, 超声, 稳定性, 化学动力学, 模型

Abstract: In this study the stability of epigallocatechin gallate (EGCG) in a weakly acidic environment alone and in combination with an ultrasonic filed of 0.25 W/cm2 and 135 kHz was quantitatively analysis by high performance liquid chromatography. It was shown that under 20 ℃ and the same pH conditions, ultrasonic treatment caused a decrease of the stability of EGCG, and the loss rate of EGCG was 10.70 %, after 40 min exposure to pH 6.2 with ultrasonic treatment, exhibiting a 5.63-fold increase compared to the absence of ultrasonic. Linear regression indicated that the reaction of EGCG in an ultrasonic field and in a nonultrasonic field followed first-order kinetics. The rate constant was 0.00228 min-1 in the presence of ultrasonic, the activation energy 22861.13 kJ/mol, and the pre-exponential factor 28.30 s-1, which were increased 4.3 times, decreased by 14.0% and increased by 13.5%, respectively.

Key words: epigallocatechin gallate, ultrasonic, stability, chemical dynamics, kinetic model

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