Effect of Phloroglucinol and Resorcinol on the Clingstone Peach Polyphenol Oxidase-catalyzed Oxidation of 4-Methylcatechol 1
AUTOR(ES)
Wong, Thomas C.
RESUMO
Phloroglucinol and resorcinol are not substrates for clingstone peach (Prunus persica) polyphenol oxidase, but they react with 4-methyl-o-quinone, produced either enzymatically or nonenzymatically, to give an intense red or red-brown color with a maximal absorption at about 470 nanometers. Several colored products were isolated from an ethyl acetate extract of the reaction by two-dimensional thin layer chromatography. Based on thin layer chromatographic and spectral studies of the enzymatic and nonenzymatic reactions, polyphenol oxidase does not play a role in the reaction between 4-methyl-o-quinone and phloroglucinol, resorcinol, d-catechin, or orcinol. In such reactions, the function of polyphenol oxidase is the formation of 4-methyl-o-quinone which then reacts nonenzymatically with the above phenols. Activation energies of both enzymatic and nonenzymatic reactions were determined.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=396793Documentos Relacionados
- Isolation and Characterization of Polyphenol Oxidase Isozymes of Clingstone Peach 1
- Polyphenol Oxidation by Vicia faba Chloroplast Membranes: STUDIES ON THE LATENT MEMBRANE-BOUND POLYPHENOL OXIDASE AND ON THE MECHANISM 1 OF PHOTOCHEMICAL POLYPHENOL OXIDATION
- Construction of Chimeric Catechol 2,3-Dioxygenase Exhibiting Improved Activity against the Suicide Inhibitor 4-Methylcatechol
- Activation of Polyphenol Oxidase of Chloroplasts 1
- Studies on Polyphenol Content, Activities and Isozymes of Polyphenol Oxidase and Peroxidase During Air-Curing in Three Tobacco Types 1
