Table 1

Glucuronidation of entacapone and tolcapone (500 μM) by different UGT sources at 50 μM and 2 mM UDP-glucuronic acid

UGT Source	Entacapone Activity		Tolcapone Activity		Control Activity
UGT Source	50 μM	2 mM	50 μM	2 mM	Substrate (500 μM)	2 mM
	nmol min⁻¹mg⁻¹		nmol min⁻¹ mg⁻¹			nmol min⁻¹ mg⁻¹
UGT1A1	0.002	0.036, 0.026^1-a	N.D.	N.D.	Octylgallate	0.81
UGT1A6	N.D.	N.D.	N.D.	N.D.	1-Naphthol	1.4
UGT1A9	0.17	1.3	0.010	0.73	Propofol	0.78
UGT2B7	0.006	0.073	0.002	0.034	4-Hydroxyestrone	0.45
UGT2B15	0.003	0.045	0.001	N.D.	8-Hydroxyquinoline	0.36
HLM	0.14	2.0	0.008	0.69
HKM	0.08	2.3	0.015	0.76

N.D., not detectable; HLM, human liver microsomes; HKM, human kidney microsomes.
↵1-a Two peaks detected.