Fig. 5

Dixon plots showing the reciprocal of the velocity (1/υ) of the mushroom tyrosinase reaction against the inhibitor 0–10 mM gallic acid (a) or gallic acid glucoside (b). Various substrate concentrations of l-DOPA (0.1, 0.5, 1.0, 5.0 mM) were applied to obtain the Dixon plots. A475 represents an increase in the absorbance at 475 nm