摘要
对金银花叶多酚氧化酶(PPO)的酶学特性进行研究。以新鲜金银花叶片为原料,采用溶剂法从中提取多酚氧化酶粗液,研究不同的温度、pH值、底物浓度、抑制剂等因素对PPO活性的影响,建立酶促褐变动力学方程。研究结果表明,金银花叶PPO的最适温度45℃,最适pH6.5,安全、经济的褐变抑制剂柠檬酸;当以邻苯二酚为底物时,金银花叶PPO活性与底物浓度关系符合米氏方程的酶促反应动力学规律,最大反应速度Vmax=313U/min,Km=0.0197mol/L。
To study the enzymatic characteristics of polyphenol oxidase（PPO） in Lonicera japonica leaves in this paper. The flesh Lonicera japonica leaves as the materia, crude PPO was extracted by buffer solution. The effect of the different temperature、 pH、 substrate concentration and inhibitors on PPO activity were studied and the reaction kinetic equation was established. The results showed that the optimum temperature, pH and inhibitors were 45 ℃, pH 6.5, and citric acid respectively. Catechol as substrate, Lonicera japonica leaves polyphenol oxidase-catalyzed reaction comply with the law of Michaelis equation The V max and K m value were 313 U/min -1 and 0.0197 mol/L, respectively.
出处
《中国食品学报》
EI
CAS
CSCD
北大核心
2012年第11期59-63,共5页
Journal of Chinese Institute Of Food Science and Technology
基金
国家自然科学基金项目(31060226)
江西省科技支撑项目(20122BBF60080)
关键词
金银花叶
多酚氧化酶
酶学特性
Lonicera japonica leaves
polyphenol oxidase
enzymatic properties
