The role of nitroaromatic compounds in the direct‐acting mutagenicity of diesel particle extracts

Abstract

The Salmonella mutation assay has been adapted to a number of experimental procedures used to characterize the chemical components and molecular mechanisms involved in the direct-acting mutagenicity of diesel particle extracts. The mutagens were found to be unreactive towards purified DNA. Mutagenic activity was decreased in nitroreductase-deficient bacteria and increased in the absence of oxygen, suggesting that bacterial enzymes active the mutagens. The extract was fractionated by thin layer chromatography using both normal and reverse phase silica gel plates. On normal silica plates, a separation was made between unsubstituted PAH, nitro-PAH and the more polar aromatic compounds. About a third of the mutagenic activity in the particle extract was recovered in fractions containing monosubstituted nitro-PAH compounds. The absorption spectra and reverse phase chromatographic properties indicate 1-nitropyrene is a predominant component but not the only mutagen in these fractions. The remaining activity was in the more polar fractions, and mutagenicity assays using anaerobic conditions and nitro-reductase-deficient bacteria suggest they contain other nitro-substituted compounds.

A Comparative Study of Physiological Activity and Ingredient Analysis of Glycyrrhiza uralensis Fischer Stems and Leaves Cultivated with Different Wavelength of LED Lights

“…적이고, 경량이면서 수명이 길고, 전력이 적게 소모된다 (Cho et al, 2005) Table 1과 같다 (Pederson et al, 1981). 있는 연구를 진행할 예정이다.…”

Temporal Patterns of Bacterial Mutagenicity on Ambient Aerosols in Southeastern Michigan

“…Fractions 1-4 (Fr 1-4) contained mostly polar compounds, Fr 5-8 the oxygenated or substituted PAH compounds, Fr 9-10 the PAH compounds, and Fr 11-16 the aliphatic compounds. Details of the procedures have been described in our earlier reports (Siak et al, 1985;Wolff et al, 1986b;Pederson and Siak, 1981a). Because of the sample mass requirements of the in vitro mutagenicity assay and the availability of other concurrent air quality data, only 24 out of the 56 pairs of day/night samples (including a data set of 10 consecutive days) were judged to be acceptable for detailed mutagenicity analysis.…”

“…A nitroreductase deficient strain of TA98, TA98/DNP6, was also used in the Ames mutagenicity assays since this strain is resistant to many nitroaromatic mutagens. Chemical separation by thin-layer chromatography provided a means to examine the mutagenicity profile for each extract, and determine the contribution from each of the polar, nonpolar, or nitroaromatic fractions (Pederson and Siak, 1981a). T h s procedure can be used to allocate the biological activities to nitrated-PAH or similar compounds such as oxygenated, nitrated, and other organic compounds.…”

Consensus report: mutagenicity and carcinogenicity of car exhausts and coal combustion emissions

“…Recently, attention has been focused on nitration of PAH since this may give rise to highly mutagenic compounds such as dinitropyrenes, which have been identified in car exhaust particles. Several independent investigators (33,(37)(38)(39)(40) have reported that nitrated PAHs (e.g., 1-nitropyrene) account for a significant portion of the direct acting mutagenicity of diesel particle extracts in Salmonella (TA 98). Another approach to identification of the mutagenic components of diesel particle organics has employed direct estimation of the mutagenic contribution from chemical analysis of the composition of the organics together with bioassay studies of identified compounds.…”