Characterization of polyphenol oxidase activity in Ataulfo mango.
Crude extracts of Ataulfo exhibited polyphenol oxidase (PPO) activity with pyrogallol, 3-methylcatechol, catechol, gallic acid, and protocatechuic acid. The substrate dependent pH optima ranged from pH 5.4 to 6.4 with Michaelis-Menten constants between 0.84 ± 0.09 and 4.6 ± 0.7 mM measured in MES or phosphate buffers. The use of acetate buffers resulted in larger Michaelis-Menten constants, up to 14.62 ± 2.03 mM. Sodium ascorbate, glutathione, and kojic acid are promising inhibitors to prevent enzymatic browning in Ataulfo. PPO activity increased with ripeness and was always higher in the skin compared to the pulp. Sodium dodecyl sulphate (SDS) enhanced PPO activity, with pulp showing a stronger increase than skin. SDS-PAGE gels stained for catecholase activity showed multiple bands, with the most prominent bands at apparent molecular weights of 53, 112, and 144 kDa.
['Cheema|Summervir|S|', 'Sommerhalter|Monika|M|']
D001205:Ascorbic Acid D004156:Catechol Oxidase D004591:Electrophoresis, Polyacrylamide Gel D004791:Enzyme Inhibitors D005978:Glutathione D007700:Kinetics D031022:Mangifera D008970:Molecular Weight D010936:Plant Extracts D011485:Protein Binding D011753:Pyrones D012967:Sodium Dodecyl Sulfate
Polyphenol oxidase Ataulfo mango Enzyme Enzyme activity