富士苹果中多酚氧化酶特性的研究  

Characters of Polyphenol Oxidase in Fuji Apple

作　　者：田兰兰[1] 郭玉蓉[1] 牛鹏飞[1] 马萍[1] 刘婧琳[1] 

机构地区：[1]陕西师范大学食品工程与营养科学学院,陕西西安710062

出　　处：《农产品加工（下）》2011年第3期20-23,39,共5页Farm Products Processing

基　　金：现代苹果产业技术体系建设(nycytx-08)

摘　　要：以富士苹果为原料,从中提取多酚氧化酶粗提液,通过底物筛选,从不同的pH值、温度和抗氧化剂对PPO酶的影响等方面进行研究。结果表明,PPO酶对4种底物催化活性不同,由高到低的顺序依次为:邻苯二酚,DL-半胱氨酸,苯甲酸,山梨酸;PPO酶的最适pH值为5.0,最适温度30℃,最佳酶浓度0.25mol/L,最佳底物浓度0.6mol/L;当VC浓度达到150mmol/L,90%的PPO酶活性被抑制。Polyphenols oxidase is one of the main reasons for the discoloration,Fuji apple as the materials in this study,from which extract the crude polyphenols oxidase liquid,select the variant substrate and different pH value,temperature,the effects of anti-oxidants on PPO enzymes.The results show that the order of different substrate specificities is o-dihydroxy benzeneDL-CysteineBenzoic acidsorbic acid,the optimum pH for PPO is 5.0,the optimum temperature for PPO is 30 ℃,the best enzyme concentration is 0.25 mol/L;the best substrate concentration is 0.6 mol/L;When the VC concentration up to 150 mmol/L,90% PPO enzyme activity is restrained.

关 键 词：多酚氧化酶 底物 邻苯二酚 抗氧化剂 

分 类 号：TS255.1[轻工技术与工程—农产品加工及贮藏工程]