Separation and characterization of gall bladder bile metabolites from speckled trout, Salvelinus fontinalis, exposed to individual polycyclic aromatic compounds

Abstract

Speckled trout, Salvelinus fontinalis, were orally exposed to individual polycyclic aromatic compounds (PACs) represented by benzo[a]pyrene, carbazole, chrysene, dibenzofuran, dibenzothiophene, fluorene, phenanthrene, and pyrene. Fish were sacrificed 7 d after exposure and the gall bladder removed for bile analysis. High pressure liquid chromatography (HPLC) with fluorescence (F) and ultraviolet (UV) detection was used to determine the presence of PAC derivatives in the bile without pretreatment. Glucuronide conjugates were predominant in all exposures with variable amounts (0-53%) of phenols and starting material. Identification of compounds was confirmed by selective extraction of less polar nonconjugated PACs and enzymatic hydrolysis of water-soluble material. This was followed by HPLC and/or gas chromatography-mass spectrometry (GCMS) characterization of the produced phenols. Total metabolite levels varied widely among compounds.

Analysis of pyrene metabolites in marine snails by liquid chromatography using fluorescence and mass spectrometry detection

“…This transition and the absence of product ions characteristic of the glucuronic acid moiety at m/z 175 and m/z 131 indicate a somewhat different gas phase fragmentation of PYOG than has been previously reported [40,53]. This difference was verified using PYOG from a laboratory reference fish bile obtained in a previous study [35]. This difference reinforces the importance of verifying MS system specific fragmentation of a compound before beginning MRM measurements.…”

“…The retention time of this standard did not match that of PYOG in a fish bile sample from a previous study [35] and was determined by LC-MS to be a methylated derivative of PYOG ([M−H] − = m/z 407). Stirring 0.95 g of this material in 10 mL methanol with excess KOH for 21 h gave complete conversion to PYOG, as determined by LC-FLD.…”

“…These provided superior sensitivity and good selectivity for the target analytes present in the whelk tissue extracts. Compared with 260/380 nm ex/em, a wavelength pair previously used for analysis of PY and its metabolites [34,35], 235/388 shows a general increase in sensitivity of about fourfold for PY, PYOH, PYOS and PYOG without an increase in interfering background from fluorescent natural products present in tissue extracts. By collecting chromatograms at both of these wavelength pairs, the relative fluorescence response can be used as a tool for identifying PY metabolites in complex extracts, especially in the absence of a scanning fluorescence detector.…”

“…As no chromatographic separation is used, analysis by the first two more frequently used techniques is not specific to the structure of phase II conjugates. In urine, bile and tissue extracts, liquid chromatography with fluorescence detection (LC-FLD) is a commonly used method to measure PYOH, PYOG and other metabolites [34][35][36]. The non-volatile nature of these metabolites and their sensitive fluorescence detection makes LC-FLD a highly suitable technique to analyze mixtures of PAH and their derivatives.…”

Protective effect of erdosteine against naphthalene-induced oxidative stress in rats

“…As a result of the release of petroleum oils to the sea PAHs are now ubiquitous contaminants of aquatic ecosystems (1). Some of these chemicals have been demonstrated to have mutagenic/carcinogenic (2, 3), genotoxic (4) and cytotoxic (5) properties (6).…”