摘要：Polyphenol oxidases are found both in prokaryotic and eukaryotic microorganisms, in mammals, invertebrates andplants. Most plants have multiple forms of PPO. The more recent articles regarding the polyphenol oxidases fro mdifferent plants arereviewed. The main characteristics considered were the sources, structure and properties ofpolyphenol oxidase (PPO) as well as the inhibitors of this enzyme. The polyphenol oxidase was extracted and purifiedfrom different plants such as parsley, banana,grapes, durum wheat, etc and it was achieved a fold p urification in therange 3.32–259 with a recovery between 5.11–44.3% The optimum pH and temperature for polyphenol oxidasesfrom various sources of plants were in the rangeof4.0–8.5 and 30oC-80oC. The affinity o f the enzyme varieddepending on the substrate used, thus the polyphenol oxidases fro m plants had the highest affinity for 4-methylcatechol,catechol and p yrogallol. For the inhibition studies, there were tested many substances but the most effective inhibitorsfor almost every PPO were: ascorbic acid, citric acid, L-cysteine and sodium metabisulfite
