Table 4.

Kinetic analysis of compounds 1c, 1h, and 2a.

	1c			1h			2a
	Vmax (mM·min−1)	KM (mM)	Ki (M)	Vmax (mM·min−1)	KM (mM)	Ki (M)	Vmax (mM·min−1)	KM (mM)	Ki (M)
2.5	-	-	-	3.1 × 10−2	5.64	4.1 × 10−7	-	-	-
5 μM	-	-	-	3.1 × 10−2	13.92	3.0 × 10−7	-	-	-
10 μM	2.7 × 10−2	12.54	1.9 × 10−6	3.1 × 10−2	26.97	3.0 × 10−7	2.9 × 10−2	7.83	3.4 × 10−6
20 μM	2.7 × 10−2	22.24	1.9 × 10−6	-	-	-	2.9 × 10−2	15.07	3.1 × 10−6
40 μM	2.7 × 10−2	41.56	2.0 × 10−6	-	-	-	2.9 × 10−2	32.42	2.6 × 10−6

Data were obtained from Lineweaver-Burk plots of mushroom tyrosinase activities. Michaelis Menten constant (K_M), V_max, and inhibitor constant (K_i) values were determined at 10, 20, or 40 μM for 1c and 2a and at 2.5, 5, or 10 μM for 1h. Data are presented as the mean values of three independent experiments conducted using L-tyrosine concentrations of 1.0, 2.0, 4.0, or 8.0 mM.