紫甘薯多酚氧化酶性质研究

Research on the Characterization of Polyphenoloxidase from Purple Sweet Potato

采用含有30 mmol/L Vc的0.01 mol/L磷酸盐缓冲液从紫甘薯中提取多酚氧化酶(PPO),用分光光度法对紫甘薯中多酚氧化酶的酶学特性进行了系统的研究,其中包括PPO的活力测定、热稳定性、pH稳定性以及pH、温度、抑制剂对PPO活力的影响。实验结果表明,多酚氧化酶催化反应的最佳条件为:温度25℃,pH 7.0,NaHSO3和Vc对酶活力有很强的抑制作用。

PPO ofpurple sweet potato was extracted by 0.01mol/L sodium phosphate buffer （pH 7.0）, contained 30 mmol/g ascorbic acid. This article made a systematic and deep research on the characterization of potato polyphenol oxidase by spectrophotometry, including the activity of polyphenoloxidase, heat stability, pH stability as well as the effects of pH, temperature, inhibitors on PPO activity. The result showed that the optimum pH and temperature were 7.0 and 25℃, ascorbic acid, Sodium Bisulfate showed a strong inhitory effect on activity of polyphenol oxidase.