Studies on the Enzymic Browning of Apples II. Properties of Apple Polyphenoloxidase

Abstract

The properties of a particulate polyphenoloxidase preparation from young apple fruit have been investigated. Chlorogenic acid, D-catechin, and hydrocaffeic acid were found to be the substrates most rapidly oxidized by this preparation, but its action on a number of other phenolic compounds was also investigated. The inhibition of the oxidation of phenolic compounds by cysteine and other thiol compounds was studied in detail.