期刊
FOOD CONTROL
卷 12, 期 2, 页码 85-90出版社
ELSEVIER SCI LTD
DOI: 10.1016/S0956-7135(00)00026-8
关键词
apple; 'Jonagored'; polyphenoloxidase
Polyphenoloxidase (PPO) was extracted from apple (cv. Jonagored) with addition of 2% PVP and 0.25% Triton X100 to the extraction buffer containing phenolic adsorbents. Experiments were performed to evaluate the affinity and specificity towards several substrates. 'Jonagored' apple PPO was found to have higher specificity (lower K-m) towards L-dopa, 4-methylcatechol and (+) catechin than other phenols tested, but the highest activity level was obtained with p-cresol. The ratio V-max/K-m indicates that p-cresol followed by L-dopa and 4-methylcatechol are the best substrates for 'Jonagored' apple PPO. The enzyme activity showed two pH optima, at 5.0 and 7.5, at room temperature, with the main peak at pH 7.5 and the secondary one at pH 5.0 when catechol was the substrate. (C) 2000 Elsevier Science Ltd. All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据