1. Alfred Wegener Institute for Polar and Marine Research, Research Department Potsdam, Telegrafenberg A45, 14473 Potsdam, Germany
2. Helmholtz Centre Potsdam, GFZ German Research Centre for Geosciences, Sektion 4.3, Organic Geochemistry, Telegrafenberg, B 423, 14473 Potsdam, Germany
3. Rheinische Friedrich-Wilhelms-Universität Bonn, Institute of Nutrition and Food Sciences, Department of Food Microbiology and Hygiene, Meckenheimer Allee 168, 53115 Bonn, Germany