Variations in IC50 Values with Purity of Mushroom Tyrosinase

Variations in IC50 Values with Purity of Mushroom Tyrosinase

The effects of various inhibitors on crude, commercial and partially purified commercial mushroom tyrosinase were examined by comparing IC(50) values. Kojic acid, salicylhydroxamic acid, tropolone, methimazole, and ammonium tetrathiomolybdate had relatively similar IC(50) values for the crude, commercial and partially purified enzyme. 4-Hexylresorcinol seemed to have a somewhat higher IC(50) va...

Purification of Tyrosinase from Edible Mushroom

Study of stereospecificity in mushroom tyrosinase.

This paper reports experiments on the stereospecificity observed in the monophenolase and diphenolase activities of mushroom tyrosinase. Several enantiomorphs of monophenols and o-diphenols were assayed: L-tyrosine, D,L-tyrosine, D-tyrosine; L-alpha-methyltyrosine, D,L-alpha-methyltyrosine; L-dopa, D,L-dopa, D-dopa; L-alpha-methyldopa, D,L-alpha-methyldopa; L-isoprenaline, D,L-isoprenaline and ...

The inhibition effects of melon on mushroom tyrosinase activity

The  inhibition effects seed and peel of melon on diphenolase activity of mashroom tyrosinase were investigated. The IC50 values and Ki values of seed and peel of melon were evaluated. increased the Km value and decreased the Vm value so it show mixed type inhibition on mushroom tyrosinase when L-DOPA was used as a substrate.

Physicochemical and kinetic properties of mushroom tyrosinase.

Tyrosinase (o-diphenol: O2 oxidoreductase, EC 1.10.3.1) has been purified from a commercial lyophilized powder prepared from edible mushrooms. Specific activities toward DL-dihydroxyphenylalanine and catechol, homogeneity, molecular weight, absorption spectrum, amino acid composition, and copper content of the preparation are comparable to other purified samples of tyrosinase prepared from fres...