Inhibitory Effect of Mutagenic Activity of Benzo[α]pyrene by Asphalt Tar Inhibition of Benzo[α]pyrene-3-Hydroxylase

Abstract

The effects of asphalt tar and its components on the mutagenic activity of benzo[α]pyrene (B[α]P) were studied. The mutagenic activity of B[α]P was inhibited significantly by the addition of asphalt tar and its components especially by those containing neutral polycyclic aromatic hydrocarbon which was obtained by the fractionation according to the method of Hoffmann et al. The above effects seemed to be due to the inhibition of the activating enzyme of B[α]P and it was demonstrated that the activity of B[α]P-3-hydroxylase was inhibited strongly by the neutral polycyclic aromatic hydrocarbon fraction of the asphalt tar in a competitive manner (K₁=4μg/ml).