In vitro enantioselective inhibition of key human CYP450 enzymes by the chiral fungicide penconazole.

Penconazole (PEN) is a chiral triazole fungicide widely used in vineyards. Despite its detection in human urine and documented toxicological effect in non-targeted organisms, data on PEN's effects in humans is scarce. This study investigated the in vitro inhibitory effects of racemic PEN and its isolated enantiomers on major CYP450 isoforms using human liver microsomes.

Enantioselective in vitro metabolism of the fungicide penconazole by human liver microsomes and in vitro-in vivo extrapolation of hepatic clearance.

Contamination by chiral compounds may cause enantioselective toxicity and bioaccumulation. For chiral pesticides like penconazole (PEN), while using a mixture containing equal amounts of enantiomers is cost-effective, chiral effects may impact both targeted and non-targeted organisms. Enantioselective toxicity has been observed during PEN exposure to albino rats and various cell types, as well as differences in fungicidal activity.

Enantioselective in vitro metabolism of the herbicide diclofop-methyl: Prediction of toxicokinetic parameters and reaction phenotyping.

Human exposure to contaminants of emerging concern, like pesticides, has increased in the past decades. Diclofop-methyl (DFM) is a chiral herbicide that is employed as a racemic mixture (rac-DFM) in soybean and other crops against wild oats. Studies have shown that DFM has enantioselective action (higher for R-DFM), degradation (faster for S-DFM), and metabolism, producing diclofop (DF) which is also a pesticide.