Thiouracil-Forming Bacteria Identified and Characterized upon Porcine In Vitro Digestion of Brassicaceae Feed

摘要: In recent years, the frequent detection of banned thyreostat thiouracil (TU) in livestock urine has been related to endogenous TU formation following digestion glucosinolate-rich Brassicaceae crops. Recently, it was demonstrated that, upon vitro Brassicaceae, fecal bacteria induce (porcine > bovines). Therefore, present study intended isolate and identify involved this intestinal gain more insight into underlying mechanism porcine livestock. Twenty inocula (gilts multiparous sows) were assessed through static colonic-digestion simulations with rapeseed. After derivatization extraction suspensions, analyzed using liquid chromatography-tandem mass spectrometry (LC-MS(2)). On average, lower concentrations observed colonic gilts (8.35 ng g(-1) rapeseed ± 3.42 [mean standard deviation]) than sows (52.63 16.17), which correlates maturation gut microbial population age. Further exploration showed cell-dependent activity conversion sustained TU-forming after subjection inoculum moderate heat over a time span up 30 min. Finally, nine TU-producing bacterial species successfully isolated identified by combination biochemical molecular techniques as Escherichia coli (n = 5), Lactobacillus reuteri 2), Enterococcus faecium 1), Salmonella enterica subsp. arizonae 1). This report demonstrates that is induced occurs under conditions most likely myrosinase-like enzyme expressed different common species.