1. Institute of Animal Nutrition and Nutrition Physiology; Justus-Liebig-University Giessen; Heinrich-Buff-Ring 26-32 35392 Giessen Germany
2. Institute of Clinical Chemistry and Laboratory Medicine; University Hospital of Regensburg; Franz-Josef-Strauss-Allee 11 93053 Regensburg Germany
3. Institute of Food Chemistry and Food Biotechnology; Justus-Liebig-University Giessen; Heinrich-Buff-Ring 17 35392 Giessen Germany
4. Fraunhofer Institute for Molecular Biology and Applied Ecology; Winchester Str. 2 35394 Giessen Germany