This is the first report of a metabolic conversion in animals of zearalenone to zearalanols. Zearalenone was labeled with deuterium by base-catalyzed isotope exchange. The labeled zearalenone, in the form of its β-cyclodextrin inclusion complex, was administered orally and intravenously to sheep. In addition to deuteriozearalenone glucuronide, analysis of the urine revealed the presence of deuteriated α- and β-zearalenol and α- and β-zearalanol glucuronides. No zearalanone was detected in the urine. The problem of cis−trans isomerization of zearalenone in the presence of sunlight is also discussed. Keywords: Zeranol; zearalanol; zearalenone; zearalenol; metabolism; residue; Fusarium; mycotoxin

It is well-known that 2D dried blood spots on paper offer a facile sample collection, storage, and transportation of blood. However, large volume requirements, possible analyte instability, and difficult sample recovery plague this method, lowering confidence in analyte quantification. For the first time, we demonstrate a new approach using 3D dried blood spheroids for stabilization of small volume blood samples, mitigating these effects without cold storage. Blood spheroids form on hydrophobic paper, preventing interaction between the sample and paper substrate, eliminating all chromatographic effects. Stability of the enzyme alanine transaminase and labile organic compounds such as cocaine and diazepam were also shown to increase in the spheroid by providing a critical radius of insulation. On-surface analysis of the dried blood spheroids using paper spray mass spectrometry resulted in sub-ng/mL limits of detection for all illicit drugs tested, representing 1 order of magnitude improvement compared with analysis from 2D dried blood spots.

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Crystals isolated from the bile of sheep affected by hepatogenous photosensitization after grazing Panicum dichotomiflorum or Panicum schinzii were soluble in acetic acid but essentially insoluble in common organic solvents. The main component of the crystals was identified by acidic and enzymatic hydrolysis, GC-MS, LSIMS, TLC, and 13C NMR spectroscopy, and X-ray analysis as the calcium salt of epismilagenin /S-D-glucuronide. The 13C NMR spectrum was fully assigned, and the structure confirmed by comparison with model compounds (17-oxoetiocholan-3a-ol glucuronide and epismilagenin). Only saponins derived from diosgenin were detected in the foliage of P. dichotomiflorum and P. schinzii. A metabolic pathway for conversion of P. dichotomiflorum and P. schinzii saponins into the major bile crystal component is proposed.

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