【摘要】 分别以邻苯二酚、愈创木酚为底物,采用分光光度计测定氧化产物的方法对香蕉皮多酚氧化酶(PPO)和过氧化物酶(POD)的性质进行研究。结果表明,PPO最适温度为30℃、最适pH5.5、Km=22.42mmol/L、Vmax=0.027OD420/min,75℃水浴处理5min基本完全失活,100℃水浴处理20s可钝化PPO活性,并且香蕉皮PPO有同工酶;香蕉皮过氧化物酶(POD)的最适pH6.0、最适温度30℃,其在80℃下处理5min后基本失活,在沸水浴25s后酶被钝化。更多还原

【Abstract】 Taking catechol and guaiacol as substrates respectively,the characteristics of polyphenol oxidase (PPO) and peroxidase(POD) from banana peel were studied by spectrophotometer. The results showed that the optimum temperature and pH of PPO were 30℃ and 5.5 respectively, Km was 22.42mmol/L, Vmax was 0.027OD420/min. The PPO was inactivated at 75℃ for 5min and the extinct condition of PPO was 20s at 100℃. In addition, the PPO isoenzymes in its mixture. The optimum temperature and pH of POD were 30℃ and 6.0, the POD was inactivated at 80℃ for 5min and the extinct condition of POD was 25s at 100℃.更多还原