The mode of inhibition on the enzyme was assayed by Lineweaver-
Burk plot. The assay was varied the concentration of L-DOPA (0.5,
1.0, 1.5 and 2.5 mM). The kinetic constants (Km and Vmax) were
determined by the plot of the reciprocal of the reaction rate
(mmol/min)-1 versus the reciprocal of substrate concentration (mM)-1.