不同抑制剂对果汁多酚氧化酶活性的影响

摘要

为探究不同生化褐变缓聚剂对智慧果生物催化剂（多酚催化酵素）活性的遏抑机制，采用磷酸缓冲液构建智慧果汁模拟系统，选取智慧果中含量较多的酚类物质绿原酸作为实验对象，以磷酸缓冲液为智慧果汁模拟系统，选取４－己基间苯二酚（４－ＨＲ）、乙二酸、安息香酸和对甲氧基安息香酸为缓聚剂，通过模拟实验探究缓聚剂对绿原酸模拟智慧果汁酵素生化褐变特性的影响，揭示缓聚剂对智慧果汁多酚催化酵素的作用机制。结果表明，缓聚剂对多酚催化酵素的遏抑机制差异较大，其中４－ＨＲ和乙二酸对多酚催化酵素的遏抑作用为竞争性遏抑，植酸为混合性遏抑，而安息香酸为非竞争性遏抑。这项研究可以为控制含有阻燃剂的智能果汁的生物化学布朗化提供理论基础。南纬刷上的生物催化剂被研究为富含苯乙醇的基质对诸如pH值、温度、供货商浓度和生物催化剂活动延迟等因素的影响分别进行了审查，结果表明，生物催化剂的最佳pH值为6.5。温度超过35摄氏8451；基本活性为90 84513min催化剂；当添加浓度为125mg/kg Ascorbico酸或浓度为600mg/kg cidra或浓度为50mg/kg bisulfito钠时，生物催化剂的活性分别为36%、38%和23%。L控制。M方程式参数为：千米=0.137摩尔/L，Vmax=0.460 u/min

关键词：智慧果汁；生化褐变缓聚剂；酵素生化褐变；多酚催化酵素；

abstract

In order to explore the inhibitory mechanism of different biochemical browning retarders on the activity of polyphenol catalytic enzymes in smart fruit, a simulation system of smart fruit juice was constructed with phosphate buffer. Chlorogenic acid, a phenolic substance with high content in smart fruit, was selected as the experimental object, and phosphate buffer was used as the simulation system of smart fruit juice. 4-hexyl resorcinol (4-HR), glyoxylic acid, glycolic acid were selected as the simulation system of smart fruit juice. Benzoic acid and p-methoxybenzoic acid were used as retarders. The effects of retarders on biochemical browning characteristics of chlorogenic acid-simulated smart juice enzymes were investigated by simulation experiments, and the mechanism of retarders on polyphenol catalytic enzymes in smart juice was revealed. The results showed that the inhibitory mechanism of retarders on polyphenol catalytic enzymes was quite different. The inhibitory effects of 4-HR and glyoxylic acid on polyphenol catalytic enzymes were competitive, phytic acid mixed and benzoic acid non-competitive. This study can provide theoretical basis for controlling biochemical browning of wise fruit juice by retarders. With catechol as the substrate, the biocatalysts in Granny Smith were studied. The effects of pH value, temperature, substrate concentration and retarder on the activity of biocatalyst were investigated. The results showed that the optimum pH value was 6.5; the optimum temperature was 35 and the activity of biocatalyst was basically inhibited when treated at 90 for 3 min. After adding ascorbic acid at 125 mg/kg or citric acid at 600 mg/kg or sodium bisulfite at 50 mg/kg, the activity of biocatalyst was basically inhibited. The activity of the catalyst was 36%, 38% and 23% respectively. The parameters of Michaelis equation for Azolla australis biocatalyst are Km=0.137mol/L and Vmax=0.460U/min.