Bacterial wax esters in recent fluvial sediments

Autor(en)

Vesna Micic Batka, Michael Kruge, Bert Engelen, Jürgen Köster, Thilo Hofmann

Abstrakt

Intensive anthropogenic activities may periodically induce a high nutrient and/or contaminant input to rivers. These fluctuations in environmental conditions affect aquatic organisms and might cause temporary algal blooms, but can also enforce some prokaryotes to accumulate storage compounds as a hedge against starvation. Such an environmental stress can be documented in the molecular record of river sediments.
We investigated the molecular record in Danube River surface and core sediments and identified wax esters (WE) with 28 to 34 carbon atoms, being most likely of bacterial origin.
The identified WE consist of various combinations of linear (n), iso (i), anteiso (ai) aliphatic acid and alcohol moieties, showing different isomeric distributions for compounds with odd and even carbon numbers.

WE concentrations in surface sediments vary from 0 to 741 µg kg-1 with a significant enrichment recorded at locations with high concentrations of organic nitrogen and total phosphorus and a relative high proportion of aquatic vs. terrestrial organic matter, all pointing to high primary productivity. In a 70 cm long core of rapidly deposited sediment WE concentrations decrease significantly with depth following first-order kinetics, suggesting a loss of WE within few years’ time.
Cluster analysis of DGGE band patterns revealed different bacterial community compositions in up- and downstream surface sediments.
WE have seldom been investigated in rivers, but we speculate that they are markers for environmental stress. Which environmental conditions encountered in these sediments cause bacteria to generate wax esters remains, however, unclear.

Organisation(en)

Externe Organisation(en)

Carl von Ossietzky Universität Oldenburg, Montclair State University

Band

89-90

Anzahl der Seiten

12

DOI

https://doi.org/10.1016/j.orggeochem.2015.10.003

Publikationsdatum

12-2015

ÖFOS 2012

104015 Organische Chemie, 104023 Umweltchemie, 104002 Analytische Chemie, 105906 Umweltgeowissenschaften

Schlagwörter

ASJC Scopus Sachgebiete

Geochemistry and Petrology

Link zum Portal

https://ucrisportal.univie.ac.at/de/publications/bacterial-wax-esters-in-recent-fluvial-sediments(17f4dc0d-a16b-4edd-9a45-83bc1e1e588b).html