Bergamottin is a competitive inhibitor of CYP1A1 and is antimutagenic in the Ames test

► Grape fruit components inhibit Cytochrome P450 enzymes. ► Bergamottin and dihydroxybergamottin inhibit the activity of CYP1A and CYP2B subfamilies. ► Naringine is not an inhibitor of Cytochrome P450 enzymes under this experimental conditions. ► Bergamottin and dihydroxybergamottin are antimutagenic against 3-methylcholanthrene and benzo[a]pyrene promutagens. ► Bergamottin is a competitive inhibitor of CYP1A1.