Polyphenol oxidase potentials of three wild mushroom species harvested from Lişer High Plateau, Trabzon

Abstract

Crude enzyme extracts were prepared from Armillaria mellea ( A. mellea), Lepista nuda ( L. nuda) and Hypholoma fasciculare ( H. fasciculare), which were harvested from the Lişer High Plateau-Maçka (Trabzon, Turkey). The crude polyphenol oxidase (PPO) extracts from each mushroom were highly active against 4-methylcatechol. Native polyacrylamide gel electrophoresis, stained by L-3,4-dihydroxyphenylalanine, showed the polyphenol oxidase potentials. The optimum pH value, for each enzyme, was 7.0. When enzyme extracts were incubated at pH 7.0 for 24 h at 4 °C, it was observed that L. nuda and H. fasciculare enzyme activities decreased by about 26% and 18%, respectively, but, A. mellea enzyme activity increased by about 11%. The temperature optima of A. mellea, L. nuda and H. fasciculare were, respectively, 30, 30 and 20 °C. Cr 3+ and Cu 2+ ions inhibited each activity. Also, sodium metabisulphite and ascorbic acid were strong inhibitors of the enzyme activities.