Effects of mushroom tyrosinase on anisaldehyde.

Anisaldehyde (p-methoxybenzaldehyde) was previously reported to inhibit the tyrosinase-catalyzed oxidation of L-3,4-dihydroxyphenylalanine (L-DOPA) noncompetitively as long as the enzyme activity was monitored by measuring dopachrome formation. However, anisaldehyde did not inhibit this oxidation if a longer reaction time was observed, although it suppressed the initial rate of oxidation to a certain extent. Anisaldehyde significantly suppressed the rate of enzymatic oxidation of L-tyrosine.