马铃薯多酚氧化酶酶学性质及酶促合成茶黄素能力对比  

Enzymatic Properties of Potato Polyphenol Oxidase and Comparison of Enzymatic Synthesis Ability of Theaflavins

作　　者：李东 张诗琪 陶迎梅 郝旺 李静雅 李宇豪 LI Dong;ZHANG Shi-qi;TAO Ying-mei;HAO Wang;LI Jing-ya;LI Yu-hao(College of Biological Engineering,Sichuan University of Science&Engineering,Yibin 644005,China)

机构地区：[1]四川轻化工大学生物工程学院,四川宜宾644005

出　　处：《中国调味品》2023年第2期188-194,共7页China Condiment

基　　金：四川苗子工程项目(2021084);四川省科技厅项目(2017NFP1068,2018NZYF0116)。

摘　　要：多酚氧化酶(polyphenol oxidase, PPO)在儿茶素转化生成茶黄素(theaflavins, TFs)的过程中起着关键作用。在酶促制备茶黄素中,不同PPO对儿茶素的催化作用导致TFs的合成量有所差异。文章分别从5个品种(黄心、黑美人、大牛角、红玫瑰、大白花)马铃薯中对PPO进行提取,用于研究不同PPO酶学性质及茶黄素的酶促制备能力。结果表明,5个品种马铃薯PPO最适反应温度为30~40℃,最适pH为6.0~7.2,最适反应底物浓度为50~60 mmol/L,在此范围内马铃薯PPO均表现出较高酶活力。在5个品种中黄心马铃薯PPO虽酶活力低于大牛角PPO,但其酶蛋白含量最高且催化合成TFs能力最强,TFs含量为129.71μg/mL,同时生成最强单体TFDG含量显著高于其他4个品种,可作为制备茶黄素最佳酶源。对比不同来源马铃薯PPO可知其酶学性质及催化合成TFs的合成量存在差异,为马铃薯PPO分离纯化提供了适宜环境和工业化生产茶黄素的酶促原料提供了参考。Polyphenol oxidase(PPO) plays a key role in the transformation process of catechins into theaflavins(TFs). In the enzymatic preparation of theaflavins, the catalytic effects of different PPOs on catechins lead to the differences in the synthesis amount of TFs. In this paper, PPO is extracted from five varieties of potatoes(yellow heart, black beauty, big bull horn, red rose, big white flower) to study the enzymatic properties of different PPOs and the enzymatic preparation ability of theaflavins. The results show that the optimal reaction temperature of PPO from the five varieties of potatoes is 30~40 ℃, the optimal pH is 6.0~7.2, and the optimal reaction substrate concentration is 50~60 mmol/L. Within this range, the potato PPOs all show higher enzyme activity. Among the five varieties, although the enzyme activity of yellow heart potato PPO is lower than that of big bull horn PPO, yellow heart potato PPO has the highest enzyme protein content and the strongest catalytic synthesis ability of TFs, with the TFs content of 129.71 μg/mL. Meanwhile, the content of the strongest monomer TFDG produced by yellow heart potato PPO is significantly higher than that of the other four varieties, which can be used as the best enzyme source for preparation of theaflutins. By comparing PPOs from different sources of potatoes, it can be found that there are differences in the enzymatic properties and the catalytic synthesis amount of TFs, which has provided a suitable environment for the separation and purification of potato PPO and references for enzymatic raw materials for the industrial production of theaflutins.

关 键 词：马铃薯多酚氧化酶 茶黄素 酶促反应 酶学性质 

分 类 号：TS201.25[轻工技术与工程—食品科学]