Table 2.

Oxidation of flavanone by human P450 enzymes

P450	Flavanone oxidation
	Formation of flavone and hydroxylated products (nmol/min/nmol P450)
	Flavone	6OHF	7OHF	6OHFva	7OHFva	2´-OHFva	3´-OHFva	4’´-OHFva
CYP1A1	0.053 ± 0.003	0.002 ± 0.001	<0.001	0.058 ± 0.008	0.007 ± 0.003	0.008 ± 0.004	0.004 ± 0.002	0.074 ± 0.002
CYP1A2	0.008 ± 0.001	<0.001	0.002 ± 0.002	0.19 ± 0.02	0.009 ± 0.001	0.074 ± 0.012	0.117 ± 0.023	0.33 ± 0.05
CYP1B1	0.046 ± 0.002	0.002 ± 0.001	<0.001	0.33 ± 0.05	0.003 ± 0.001	0.046 ± 0.009	0.013 ± 0.002	0.19 ± 0.04
CYP2A6	0.72 ± 0.06	0.003 ± 0.001	<0.001	1.29 ± 0.08	<0.001	4.76 ± 0.32	0.031 ± 0.003	0.20 ± 0.01
CYP2A13	0.29 ± 0.02	0.004 ± 0.001	<0.001	0.17 ± 0.01	0.005 ± 0.001	0.027 ± 0.002	0.011 ± 0.004	0.013 ± 0.001
CYP2C9	0.009 ± 0.002	<0.001	<0.001	0.091± 0.001	<0.001	0.012 ± 0.001	0.003± 0.001	0.040± 0.001
CYP3A4	0.057 ± 0.011	<0.001	<0.001	<0.001	<0.001	<0.001	<0.001	<0.001

Abbreviations used: 6OHF, 6-hydroxyflavone; 7OHF, 7-hydroxyflavone; 6OHFva, 6-hydroxyflavanone; 7OHFva, 7-hydroxyflavanone 2´OHFva, 2´-hydroxyflavanone; 3´OHFva, 3´-hydroxyflavanone; 4´OHFva, 4´-hydroxyflavanone.

Data are presented as means and SD (range) of duplicate determinations.