Javascript är avstängt eller blockerat i din webbläsare. Detta kan leda till att vissa delar av vår webbplats inte fungerar som de ska. Sätt på javascript för optimal funktionalitet och utseende.

Webbläsaren som du använder stöds inte av denna webbplats. Alla versioner av Internet Explorer stöds inte längre, av oss eller Microsoft (läs mer här: * https://www.microsoft.com/en-us/microsoft-365/windows/end-of-ie-support).

Var god och använd en modern webbläsare för att ta del av denna webbplats, som t.ex. nyaste versioner av Edge, Chrome, Firefox eller Safari osv.

Johan Lindgren

Johan Lindgren

Universitetslektor

Johan Lindgren

Occurrence and fate of fatty acyl biomarkers in an ancient whale bone (Oligocene, El Cien Formation, Mexico)

Författare

  • Volker Thiel
  • Martin Blumenberg
  • Steffen Kiel
  • Tim Leefmann
  • Katharina Liebenau
  • Johan Lindgren
  • Peter Sjovall
  • Tina Treude
  • Thomas Zilla

Summary, in English

The taphonomic and diagenetic processes by which organic substances are preserved in animal remains are not completely known and the originality of putative metazoan biomolecules in fossil samples is a matter of scientific discussion. Here we report on biomarker information preserved in a fossil whale bone from an Oligocene phosphatic limestone (El Cien Fm., Mexico), with a focus on fatty acyl compounds. Extracts were quantitatively analysed using gas chromatography-mass spectrometry (GC-MS) and, to identify macromolecular-linked remains, demineralised extraction residues were subjected to catalytic hydropyrolysis (HyPy). To better recognise potential authentic (i.e. animal-derived) lipids, the data from the ancient bone were compared with those obtained from (i) the adjacent host sediment of the fossil and (ii) a recent whale (Phocoena phocoena) vertebra. In addition, the spatial distribution of organic and inorganic species was observed at the mu m level by imaging MS (time-of-flight-secondary ion mass spectrometry, ToF-SIMS). Our results revealed a rather even distribution of hydrocarbon-, O- and N-containing ions in the trabecular network of the ancient bone. A different, more patchy arrangement of organic compounds was evident in the former marrow cavities that were partly cemented by clotted micrites of putative microbial origin. The concentration of fatty acids (FAs) in the ancient bone was in the permil range of the amount extracted from the recent whale vertebra. Endogenous compounds, including monoenoic n-C-16 and n-C-18 as well as branched FAs, were identified in the fossil bone by comparison with the host sediment. Ca. 80% of the prevalent n-C-16 and n-C-18 moieties in the ancient bone were extractable as FAs, whereas ca. 20% were covalently bound in the non-saponifiable kerogen fraction. Ample pyrite precipitates, distinctive 10-methyl branched FAs and microbial microborings ("tunneling") indicate that sulfate reducers and collagen-degrading actinomycetes were central players in the microbial decomposition of the bone. Similarities with reported microbial FA patterns suggest that the FAs in the fossil bone were largely contributed by these microbial "last eaters". The results highlight some of the degradation and preservation mechanisms during marine FA diagenesis in the "natural laboratory" of bones, and therefore the processes that lead to either degradation, preservation, or introduction of these widespread biomolecules in the fossils of ancient marine animals. (C) 2013 Elsevier Ltd. All rights reserved.

Avdelning/ar

  • Berggrundsgeologi

Publiceringsår

2014

Språk

Engelska

Sidor

71-81

Publikation/Tidskrift/Serie

Organic Geochemistry

Volym

68

Dokumenttyp

Artikel i tidskrift

Förlag

Elsevier

Ämne

  • Geology

Status

Published

ISBN/ISSN/Övrigt

  • ISSN: 1873-5290