14C-Ethion residues in soybean seeds: metabolic pathway, effect of processing, bioavailability, toxicity and protective action of artichoke leaf powder towards rats

Abstract

The metabolic fate of ethion labeled with 14C-at the ethyl ester groups in soybean seeds following topical application to leaves was studied. Chromatographic analysis of soybean oil revealed the presence of the parent compound together with four metabolites which were identified as ethion monooxon, ethion dioxon, O-ethyl phosphorothioate and O,O-diethyl phosphorothioate. The effect of processing on ethion residues in soybean oil was investigated. The refined oil contained small amounts of the 14C-residues originally present (37.5%). Upon feeding rats with the cake containing ethion bound residues, a substantial amount of 14C-residues was eliminated in the urine (73%), and about 6% excreted with the feces. About 5% of the radioactive residues were distributed among various organs. Mature male Wistar rats were fed on soybean seeds containing ethion residues (1.93 ppm), and on artichoke leaves powder (1% W/W) for four weeks. At the end of the experimental period, the ethion-treated group had a significantly higher alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP) activity, urea, creatinine, total cholesterol (TC), triglycerides (TG), and very low density lipoprotein (VLDL) levels. The ethion-treated rats also had a lower total serum protein and albumin levels, as well as acetyl cholinesterase (AChE), catalase (CAT), and glutathione-S-transferase (GST) activity as compared with controls. Moreover, concomitant treatment with artichoke leaf powder improved, at least partially, all the biochemical parameters that were altered by ethion.