Historical Insights Into the Purification of Polyphenol Oxidase From Plants

Over the past 50 years, different methods have been developed to purify polyphenol oxidase (PPO), a key enzyme involved in the oxidation of phenolic compounds in plants. This review presents a comprehensive summary of the advances in purification techniques, highlighting the evolution of the methods used over the years to achieve partially purified or pure enzymes, while also discussing their advantages and limitations. Furthermore, this review examines the biochemical properties of PPO that are most significant for its potential biotechnological applications. A comparison of the amino acid sequences and tertiary structures of crystallized PPO is also included, enabling the identification of structural similarities among PPO from different species. Finally, this review has been written as a guide for decision-making regarding the selection of an appropriate PPO purification strategy, taking into account the required level of purification and the enzyme's source.