Variations in IC(50) 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) value using crude extracts, compared to commercial or purified tyrosinase. Some inhibitors (NaCl, esculetin, biphenol, phloridzin) showed variations in IC(50) values between the enzyme samples. In contrast, hydroquinone, lysozyme, Zn(2+), and anisaldehyde showed little or no inhibition in concentration ranges reported to be effective inhibitors. Organic solvents (DMSO and ethanol) had IC(50) values that were similar for some of the tyrosinase samples. Depending of the source of tyrosinase and choice of inhibitor, variations in IC(50) values were observed.
Neeley
Elizabeth
E
Department of Chemistry and Physics, Indiana State University, Terre Haute, IN 47809, USA.
Fritch
George
G
Department of Chemistry and Physics, Indiana State University, Terre Haute, IN 47809, USA.
Fuller
Autumn
A
Department of Chemistry and Physics, Indiana State University, Terre Haute, IN 47809, USA.
Wolfe
Jordan
J
Department of Chemistry and Physics, Indiana State University, Terre Haute, IN 47809, USA.
Wright
Jessica
J
Department of Chemistry and Physics, Indiana State University, Terre Haute, IN 47809, USA.
Flurkey
William
W
Department of Chemistry and Physics, Indiana State University, Terre Haute, IN 47809, USA.
D000363:Agaricales / Q000201:enzymology; D057075:Enzyme Assays; D004791:Enzyme Inhibitors / Q000737:chemistry*; D005656:Fungal Proteins / Q000037:antagonists & inhibitors / Q000737:chemistry* / Q000302:isolation & purification; D006873:Hydroquinones / Q000737:chemistry; D014442:Monophenol Monooxygenase / Q000037:antagonists & inhibitors / Q000737:chemistry* / Q000302:isolation & purification; D014443:Tyrosine / Q000737:chemistry; D014468:Umbelliferones / Q000737:chemistry
D004791:Enzyme Inhibitors; D005656:Fungal Proteins; D006873:Hydroquinones; D014468:Umbelliferones; D014443:Tyrosine; D014442:Monophenol Monooxygenase; C007628:esculetin; C031927:hydroquinone