Study on enzymatic characteristics of Polyphenol Oxidase( PPO) in pomelo

Using catechol as substrates,the characteristics of polyphenol oxidase( PPO) extracted from pomelo were studied by spectrophotometer. The results showed that the maximum absorption wavelength of PPO was422nm,the optimum range of temperature and pH of PPO were 50~70℃ and 6.0~6.6 respectively.K m was 0.947mol /L,V max was 0.375U /min.The PPO was inactivated when the temperature was higher than 80℃.