Polyphenol oxidases (PPOs) are a group of metalloenzymes containing copper plastid that can catalyze the oxidation of polyphenols, which widely exist in plants, animals, and microorganisms. On the one hand, they play an important role in the physiological functions of plants; on the other hand, they also cause a decline in fruit and vegetable quality, thereby resulting in a large number of economic losses. In this paper, the physiological function, extraction and purification, and enzymatic properties of PPOs, as well as the different methods for inhibiting PPO acticity for enzymatic browning ...
