摘要:采用0.2mol/L磷酸鹽緩沖溶液勻漿法從雞腿菇和白靈菇中提取多酚氧化酶(PPO)，并對該多酚氧化酶的酶學特性進行了研究。實驗結果表明，以鄰苯二酚為底物，白靈菇中的多酚氧化酶的最適pH值為5.6，最適溫度為40℃，Km值為9.36×10-3mol/L，Vmax值為8.11×10-3U/min，100℃熱處理1.5min、95℃熱處理2.5min或90℃熱處理3.5min可完全鈍化PPO的活性，10mmol/L的異VC鈉能有效抑制PPO的酶活性；雞腿菇中的多酚氧化酶的最適pH值為4.4，最適溫度為35℃，Km值為13.5×10-3mol/L，Vmax值為8.97×10-3U/min，100℃熱處理1.5min、95℃熱處理3min或90℃熱處理4min可完全鈍化PPO的活性，10mmol/L的L-半胱氨酸能有效抑制PPO的酶活性。 

關鍵詞：白靈菇；雞腿菇；多酚氧化酶；特性

Abstract:The polyphenol oxidase (PPO) of Pleurotus Nebrodensis and Coprinus comatus were extracted by 0.2 mol/L phosphate buffer and its properties was analysed. Experimental results showed that the Pleurotus Nebrodensis optimal pH and temperature were 5.6 and 40℃ respectively, and the Km value and Vmax value with catechol substrate were 9.36×10-3mol/L   and 8.11×10-3 U/min respectively, and the PPO would be inactive in 1.5 min, 2.5 min or 3.5min, when the water tempreture was 100℃, 95℃, 90℃individually. D-Isoascorbic acid was strong inhibitors, and the effective concentration of the inhibitor was 10mmol/L.And that the Coprinus comatus optimal pH and temperature were 4.4 and 35℃ respectively, and the Km value and Vmax value with catechol substrate were 13.5×10-3mol/L and 8.97×10-3U/min respectively, and the PPO would be inactive in 1.5 min, 3 min or 4 min, when the water tempreture was 100℃,95℃,90℃, individually. L-cysteine was strong inhibitors, and the effective concentration of the inhibitor was 10mmol/L.

Keywords: Pleurotus Nebrodensis; Coprinus comatus; PPO ; Property