山药多酚氧化酶部分特性的研究

采用分光光度法测定波长410nm处山药多酚氧化酶（PPO）的活性，研究了pH、温度、底物浓度、vmax和Km值以及抑制剂对山药PPO活性的影响．结果表明。山药PPO的最适pH=6．0，最适温度为35℃，底物浓度低于0．06moL·L^-1时。山药PPO活性与底物浓度呈线性关系，其Km=0．078moL·L^-1，Vmax=0．259（△OD·min^-1），抑制剂柠檬酸、苹果酸、L-抗坏血酸对山药PPO活性均有抑制作用．

Study on Partial Characteristics of Polyphenol Oxidase in Rhizoma Dioscoreae

With Spectrophotometric the activity of Polyphenol Oxidase（PPO） in Rhizoma Dioscoreae using 410nm wavelength were determined. The influence of pH temperature, substrate concentration, the vmax and the Km,inhibitor on PPO in Rhizoma Dioscoreae were studied. The results indicated that the optimum pH was 6. 0, the optimum temperature was 35℃ of PPO, substrate concentration below 0. 06moL·L^-1,PPO activity and substrate concentration is linear,the vmax and the Km for PPO was 0. 259 （△OD·L^-1） and 0. 078moL·L^-1 ,the activity of PPO was inhibited by the inhibitor of citric acid, malic acid, L-- ascorbic acid.