Fig. 4.

Chromatograms are the result of product Total Ion Current (TIC) of thiabendazole (TBZ) or oxfendazole (OxBZ) parental drug and its metabolites identified in the supernatant of cultures of C. elegans benzimidazole resistant allele CB3474 ben-1(e1880)III (shown in green) or of adult H. contortus drug sensitive MHco3(ISE) allele (shown in orange). The first (top) chromatogram corresponds to the culture containing benzimidazole but no nematodes. The second chromatogram corresponds to the culture containing either C. elegans or H. contortus respectively, exposed to the benzimidazole. The third chromatogram corresponds to the control culture containing C. elegans or H. contortus but with no benzimidazole. C. elegans was exposed to 56.5 μM BZ for 3 days, and H. contortus was exposed to 10 μM BZ for 16 h respectively. LC-MS/MS fragmentation patterns identified in supernatant of the TBZ-treated C. elegans or adult H. contortus cultures. These fragmentation patterns were extracted from a Total Ion Current (TIC) and resulted from a fragmentor setting of 150 V and a collision energy of 30eV. A. TIC scan of C. elegans exposed to thiabendazole (TBZ), B. TIC scan of H. contortus exposed to thiabendazole (TBZ), C. Metabolite 8 and its LC-MS/MS fragmentation pattern, D. TIC scan of C. elegans exposed to oxfendazole (OxBZ), E. TIC scan of H. contortus exposed to oxfendazole, F. Proposed structure of metabolite 8. (For interpretation of the references to color in this figure legend, the reader is referred to the Web version of this article).