TABLE 3

Allosteric effects of berberine on MDZ hydroxylation in HLMs

Values denote means ± S.D. of four separate experiments. Km and Ki are given in micromolar; Vmax is in picomoles per minute per milligram microsomal protein; Vmax/Km is in microliters per minute per milligram protein.

Berberine (μM)1′-Hydroxy MDZ4-Hydroxy MDZ
KmVmaxVmax/KmKiKmVmaxVmax/Km
02.29 ± 0.292110 ± 380930 ± 220315 ± 9221.1 ± 4.41260 ± 22060.8 ± 9.4
51.63 ± 0.412080 ± 3801330 ± 370301 ± 8625.3 ± 6.21150 ± 23048.3 ± 16.5
251.58 ± 0.122280 ± 3301450 ± 210202 ± 2826.6 ± 4.5960 ± 18037.1 ± 10.1
501.22 ± 0.182010 ± 2201680 ± 300156 ± 1728.8 ± 6.5680 ± 13026.6 ± 7.9
1001.06 ± 0.151880 ± 1201810 ± 310130 ± 1723.2 ± 4.3450 ± 6020.0 ± 3.6