Comparison of the Prevention of Aflatoxin B1-Induced Genotoxicity by Quercetin and Quercetin Pentaacetate

Earlier work carried out in our laboratory highlighted the mode of action of acetoxy 4-methylcoumarins in preventing the genotoxicity of aflatoxin B1 (AFB1). We have in this report extended the observations to quercetin pentaacetate (QPA), which unlike quercetin (Q) has demonstrated time-dependent inhibition of liver microsome catalysed AFB1 epoxidation as measured by AFB1 binding to DNA. The action of QPA is similar to that of the acetoxy 4-methylcoumarins in that they are acted upon by microsomal transacetylase leading to modulation of catalytic activities of certain enzymes (such as P-450 enzymes, NADPH cytochrome C reductase and glutathione S-transferase) possibly by way of protein acetylation. In the present work, we have documented the transacetylase-mediated action of QPA in preventing genotoxicity due to AFB1.