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Enzymatic Synthesis of Epoxidized Metabolites of Docosahexaenoic, Eicosapentaenoic, and Arachidonic Acids
Published on: June 28, 2019
Characterization of an abundant and novel methyl- and methoxy-substituted brominated diphenyl ether isolated from
Maria Unger1, Lillemor Asplund, Göran Marsh
1Department of Applied Environmental Science (ITM), Stockholm University, Sweden.
Abstract:
A previously unidentified yet abundant substituted polybrominated diphenyl ether (PBDE) was isolated from a northern bottlenose whale (Hyperoodon ampullatus) found dead in the Skagerrak, North Sea. A combination of gas chromatography, high and low resolution mass spectrometry and nuclear magnetic resonance spectroscopy (NMR) ((1)H, (1)H-(1)H and (1)H-(13)C) after isolation with preparative capillary gas chromatography (PCGC) lead to the identification of the unknown substance as 6-MeO-5-Me-2,2',3,4'-tetrabromo diphenyl ether (6-MeO-5-Me-BDE42). To our knowledge this is only the second time PCGC has been used to isolate individual organohalogen compounds present in trace amounts for identification with NMR. The concentration of this novel bioaccumulated compound was estimated to be about 100 ng g(-1) lipid, which was 2.5 times higher compared with the most abundant MeO-PBDE congeners.
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