A cytochrome P450 monooxygenase involved in the metabolism of various endogenous substrates, including fatty acids, steroid hormones and vitamins. Mechanistically, uses molecular oxygen inserting one oxygen atom into a substrate, and reducing the second into a water molecule, with two electrons provided by NADPH via cytochrome P450 reductase (NADPH--hemoprotein reductase). Catalyzes the hydroxylation of carbon-hydrogen bonds. Exhibits high catalytic activity for the formation of hydroxyestrogens from estrone (E1) and 17beta-estradiol (E2), namely 2-hydroxy E1 and E2. Metabolizes cholesterol toward 25-hydroxycholesterol, a physiological regulator of cellular cholesterol homeostasis. May act as a major enzyme for all-trans retinoic acid biosynthesis in the liver. Catalyzes two successive oxidative transformation of all-trans retinol to all-trans retinal and then to the active form all-trans retinoic acid. Primarily catalyzes stereoselective epoxidation of the last double bond of polyunsaturated fatty acids (PUFA), displaying a strong preference for the (R,S) stereoisomer. Catalyzes bisallylic hydroxylation and omega-1 hydroxylation of PUFA. May also participate in eicosanoids metabolism by converting hydroperoxide species into oxo metabolites (lipoxygenase-like reaction, NADPH-independent). Plays a role in the oxidative metabolism of xenobiotics. Catalyzes the N-hydroxylation of heterocyclic amines and the O-deethylation of phenacetin. Metabolizes caffeine via N3-demethylation. an organic molecule + O2 + reduced [NADPH--hemoprotein reductase] = an alcohol + H(+) + H2O + oxidized [NADPH--hemoprotein reductase] 17beta-estradiol + O2 + reduced [NADPH--hemoprotein reductase] = 2-hydroxy-17beta-estradiol + H(+) + H2O + oxidized [NADPH--hemoprotein reductase] 17beta-estradiol + O2 + reduced [NADPH--hemoprotein reductase] = 4-hydroxy-17beta-estradiol + H(+) + H2O + oxidized [NADPH--hemoprotein reductase] estrone + O2 + reduced [NADPH--hemoprotein reductase] = 2-hydroxyestrone + H(+) + H2O + oxidized [NADPH--hemoprotein reductase] estrone + O2 + reduced [NADPH--hemoprotein reductase] = 4-hydroxyestrone + H(+) + H2O + oxidized [NADPH--hemoprotein reductase] cholesterol + O2 + reduced [NADPH--hemoprotein reductase] = 25-hydroxycholesterol + H(+) + H2O + oxidized [NADPH--hemoprotein reductase] all-trans-retinol + O2 + reduced [NADPH--hemoprotein reductase] = all-trans-retinal + H(+) + 2 H2O + oxidized [NADPH--hemoprotein reductase] all-trans-retinal + O2 + reduced [NADPH--hemoprotein reductase] = all-trans-retinoate + 2 H(+) + H2O + oxidized [NADPH--hemoprotein reductase] (5Z,8Z,11Z,14Z)-eicosatetraenoate + O2 + reduced [NADPH--hemoprotein reductase] = (14R,15S)-epoxy-(5Z,8Z,11Z)-eicosatrienoate + H(+) + H2O + oxidized [NADPH--hemoprotein reductase] (5Z,8Z,11Z,14Z)-eicosatetraenoate + O2 + reduced [NADPH--hemoprotein reductase] = (14S,15R)-epoxy-(5Z,8Z,11Z)-eicosatrienoate + H(+) + H2O + oxidized [NADPH--hemoprotein reductase] (5Z,8Z,11Z,14Z,17Z)-eicosapentaenoate + O2 + reduced [NADPH--hemoprotein reductase] = (17R,18S)-epoxy-(5Z,8Z,11Z,14Z)-eicosatetraenoate + H(+) + H2O + oxidized [NADPH--hemoprotein reductase] (4Z,7Z,10Z,13Z,16Z,19Z)-docosahexaenoate + O2 + reduced [NADPH--hemoprotein reductase] = (19R,20S)-epoxy-(4Z,7Z,10Z,13Z,16Z)-docosapentaenoate + H(+) + H2O + oxidized [NADPH--hemoprotein reductase] (5S)-hydroperoxy-(6E,8Z,11Z,14Z)-eicosatetraenoate = 5-oxo-(6E,8Z,11Z,14Z)-eicosatetraenoate + H2O (12S)-hydroperoxy-(5Z,8Z,10E,14Z)-eicosatetraenoate = 12-oxo-(5Z,8Z,10E,14Z)-eicosatetraenoate + H2O (15S)-hydroperoxy-(5Z,8Z,11Z,13E)-eicosatetraenoate = 15-oxo-(5Z,8Z,11Z,13E)-eicosatetraenoate + H2O (13S)-hydroperoxy-(9Z,11E)-octadecadienoate = 13-oxo-(9Z,11E)-octadecadienoate + H2O (5Z,8Z,11Z,14Z)-eicosatetraenoate + O2 + reduced [NADPH--hemoprotein reductase] = 13-hydroxy-(5Z,8Z,11Z,14Z)-eicosatetraenoate + H(+) + H2O + oxidized [NADPH--hemoprotein reductase] (5Z,8Z,11Z,14Z)-eicosatetraenoate + O2 + reduced [NADPH--hemoprotein reductase] = 19-hydroxy-(5Z,8Z,11Z,14Z)-eicosatetraenoate + H(+) + H2O + oxidized [NADPH--hemoprotein reductase] (9Z,12Z)-octadecadienoate + O2 + reduced [NADPH--hemoprotein reductase] = 11-hydroxy-(9Z,12Z)-octadecadienoate + H(+) + H2O + oxidized [NADPH--hemoprotein reductase] Cofactor metabolism; retinol metabolism. Steroid metabolism; cholesterol metabolism. Lipid metabolism; arachidonate metabolism. Interacts with PGRMC1; the interaction requires PGRMC1 homodimerization. By 3-methylcholanthrene (3MC). Belongs to the cytochrome P450 family.