摘要
经（ＮＨ４）２ＳＯ４分级沉淀、透析等步骤，使肥城桃多酚氧化酶部分纯化，纯化倍数为５．１１倍。该酶对邻苯二酚、焦酚和ＤＬ──二羟基苯丙氨酸显示活性，其中焦酚是最佳底物。这种多酚氧化酶的最适ｐＨ值为６．８，在３５℃下放置３０ｍｉｎ其活性不会降低。以不同的化合物作为抑制剂对该酶的催化反应进行试验，结果表明，硫脲和Ｎａ２Ｓ２Ｏ３·５Ｈ２Ｏ的抑制作用很强，在０．４３ｍＭ浓度下，抑制率分别为８０．５％和１００％。
Polyphenol oxidase (PPO) has been partially purified from P. persica (Feicheng peach). At the end of the (NH4)2SO4 precipitation and dialysis step, 5.11-fold purification was achieved. The enzyme was active in catechol,pyrogallol or DL-DOPA among of which pyrogallol was the best substrate. The optimum pH for the PPO was 6.8. The PPO activity at 35℃ did not decrease in 30 min. The effects of various compounds as inhibitors of the reaction catalysed by the enzyme were tested. These results revealed that the inhibitory effects of thiourea and Na2S2O3·5H2O were very strong,the inhibition at 0. 43 mM were 80. 5% and 100% respectively
出处
《山东农业大学学报（自然科学版）》
CSCD
1996年第1期87-92,共6页
Journal of Shandong Agricultural University：Natural Science Edition
关键词
桃
多酚氧化酶
纯化
性质
Prunus persica
polyphenol oxidase
purification
characterization
