Peptide conjugates of benzene and toluene metabolites in English ryegrass

Metabolic Fate of [14C] Chlorophenols in Radish (Raphanus sativus), Lettuce (Lactuca sativa), and Spinach (Spinacia oleracea)

“…In addition, numerous glycosyltransferases have been shown to be involved in the detoxification of endogenous substrates with parallel activity toward xenobiotics including pesticides and pollutants such as 2,4,5-trichlorophenol and 3,4-dichloroaniline − . Transformation by conjugation with low molecular mass peptides has been described in plants such as maize, pea, and English ryegrass for phenols and benzoic acid , , but no such compound could be identified in our study. We detected acetyl glycoside conjugates as main compounds in the metabolism of 4-CP in radish, 2,4-DCP in all three plants, and 2,4,5-TCP in lettuce ( Table ).…”

“…Peak 4 accounted for 70.4 ( 3.5% of the TER and was further analyzed by ESI-MS. Using both negative and positive ionization modes, the quasi-molecular species (i.e., [M-H]at m/z 501 and [M+Li] + at m/z 509, respectively, for the 35 Cl 3 isotopomer) were consistent with a structure corresponding to 2,4,5-TCP conjugated to a hexose and a C 5 H 5 O 5 moiety (Table 1). This metabolite was also submitted to 1 H NMR spectroscopy analysis, which confirmed the occurrence of a 2,4,5-TCP-O-βglucose conjugate (Table 2).…”

“…All analyses were performed under automatic gain control conditions using helium as damping as well as collision gas for MS/MS experiments. Unless specified in the text, all tandem mass spectrometric experiments were performed on the 35 Cl, 35 Cl2, and 35 Cl3 monoisotopic peaks of 4-CP, 2,4-DCP, and 2,4,5-TCP metabolites, respectively. Nuclear Magnetic Resonance Spectroscopy (Table 2).…”

“…The peak was submitted to MS analysis, which revealed the presence of two metabolites. The major compound displayed an [M-H]ion at m/z 399 for the 35 Cl 3 isotopomer, for which MS/MS analysis gave a unique fragment ion at m/z 195 corresponding to the 2,4,5-TCP moiety. On the same basis as for 2,4-DCP, this metabolite was identified as the 2,4,5-TCP-(O-acetyl)-glucoside (Table 1).…”