Aromatic hydrocarbon

About: Aromatic hydrocarbon is a research topic. Over the lifetime, 5814 publications have been published within this topic receiving 55499 citations. The topic is also known as: arene & arenes.

Synchronous fluorescence spectroscopy and its application to indigenous and petroleum-derived hydrocarbons in Lacustrine sediments

Abstract: A comparison of conventional fluorescence emission spectra and spectra produced by synchronously scanning both excitation and emission monochromators is made on a series of standard oils to demonstrate the increased resolution achieved by the synchronous technique. Greater information on the aromatic content of the oils is obtained by separating the aromatic hydrocarbon fractions by liquid-solid column chromatography prior to fluorescence analysis. Fluorescence spectroscopy, in particular the synchronous method, is used to characterize the indigenous and petroleum-derived aromatic hydrocarbons in sediments of Lake Washington, Wash.

Effect-directed analysis of mutagens and ethoxyresorufin-o-deethylase inducers in aquatic sediments.

Abstract: Sediment extracts from a creek in the Neckar river basin (Germany), which received the discharge of treated hospital wastewater, were found to exhibit strong aromatic hydrocarbon (Ah) receptor-mediated effects in a rainbow trout liver cell line (RTL-W1) as well as high mutagenicity in the Salmonella/microsome assay after fractionation. The crude extract did not exhibit a clear mutagenic response. Apparently, cleanup or fractionation before mutagenicity testing is necessary to minimize the risk of false-negative results. Effect-directed fractionation and analysis were applied to characterize and identify the toxicants that cause these effects. Major ethoxyresorufin-O-deethylase induction potency and mutagenicity were detected in different polyaromatic fractions, indicating different sets of toxicants that induce metabolic activation and mutagenicity. Dioxin-like halogenated aromatic hydrocarbons, including polychlorinated biphenyls, naphthalenes, dibenzo-p-dioxins and furans, and priority polycyclic aromatic hydrocarbons, contributed to Ah receptor-mediated activity only to a minor extent. Benzo[a]pyrene, benzo[a]fluoranthene, and perylene could be confirmed as important contributors to mutagenicity. The nonpriority pollutants 11H-indeno[2,1,7-cde]pyrene, a methylbenzo[e]pyrene, and a methylperylene were tentatively identified as major components, representing 82% of the peak area of a highly mutagenic fraction of the sediment extract. This suggests that hazard and risk assessment of complex environmental mixtures should make increasing attempts to identify and consider hazardous key pollutants rather than focusing on a priori-selected key pollutants alone.

Metabolism of Naphthalene by the Cyanobacterium Oscillatoria sp., Strain JCM

Abstract: SUMMARY: Oscillatoria sp., strain JCM grown photoautotrophically in the presence of naphthalene oxidized the aromatic hydrocarbon to cis-1,2-dihydroxy-1,2-dihydronaphthalene, 4-hydroxy-1-tetralone and 1-naphthol. The major metabolite was 1-naphthol. Each product was isolated and shown to have ultraviolet and mass spectra identical to those of authentic compounds. In addition, each metabolite had properties identical to those of authentic compounds when analysed by thin-layer, high-pressure liquid and gas-liquid chromatography. Experiments with [14C]naphthalene showed that, over a 24 h period, the organism oxidized 4.8 % of the added naphthalene. The ratio of organic-soluble to water-soluble metabolites was 41:59. Incubation of whole organisms with naphthalene and 18O2 led to the isolation of 1-naphthol that contained 18O. The organism oxidized 1-[14C]naphthol to 4-hydroxy-1-tetralone. The mechanism of naphthalene oxidation by this cyanobacterium is discussed.