In vitro oxidation promoted by chlorpyrifos residues on myosin and chicken breast proteins.

Organophosphate pesticides are frequently used to eliminate or prevent insects in poultry. However, their residues may continue in meat after slaughtering. In this study, proteomics and peptidomics approaches were used to evaluate their oxidative impact on myosin and chicken breast proteins under in vitro conditions. Myosin protein was exposed to diazinon and chlorpyrifos showing an increase in its oxidation by increasing times, especially with chlorpyrifos. Then, chicken breast was contaminated with chlorpyrifos to evaluate carbonylation and the effect of simulated gastrointestinal digestion. Proteins were isolated using size-exclusion-chromatography and identified by mass spectrometry in tandem. Myosin, β-enolase, CK-M-type and actin were identified as main proteins susceptible to oxidation. Also, oxidised peptides obtained before and after simulated gastrointestinal digestion were identified. Collagen peptides the most susceptible to oxidation. These results suggest that the presence of chlorpyrifos residues on meat could have a negative effect on its final quality and nutritional value.