Table 2. IC₅₀ and K_i values of MH against human CYP isoforms compared with that of specific inhibitors reported in literature.

CYP	Activity	IC50 (µM)		Ki (µM)
		MH	Specific inhibitor/reported valuesa	MH	Specific inhibitor/reported valuesa
CYP1A2	Phenacetin O-deethylation	4.47(3.10,6.23)b	FUR/1.4 [27]	4.56	FUR/3 [28]
CYP2A6	coumarin 7-hydroxylation	>100	TRA/0.42±0.07 [29]	-	TRA/0.17 [29]
CYP2C9	tolbutamide 4-hydroxylation	>100	SUL/0.3–1.5 [27], [30]	-	SUL/0.3 [28]
CYP2D6	metoprolol α-hydroxylation	>100	QUI/0.02–0.68 [27], [30]	-	SUL/0.027–0.4 [28], [31], [32]
CYP2E1	chlorzoxazone 6-hydroxylation	>100	DIE/21.30 [27]	-	CHL/12 [33]
CYP2C19	S-Mephenytoin 4-hydroxylation	10.91(8.84,13.45)b	TCL/0.52–1.6 [30]	42.65	TCL/1.2±0.5 [28]
CYP3A4	midazolam 1-hydroxylation	>100	KET/0.08–0.24 [28]	–	KET/0.015 [28]

^a IC₅₀ and K_i values of specific inhibitors were referred to the reported literatures. ^b represents 95% confidence interval. “–”represents the data that is not calculated. FUR, furafylline; TRA, trans-2-phenylcyclopropylamine hydrochloride; SUL, sulfaphenazole; QUI, quinidine; CHL, chlormethiazole hydrochloride; TIC, ticlopidine hydrochloride; KET, ketoconazole; DIE: diethyldithiocarbamate.