1. Department of Food Chemistry, University of Wuerzburg, Am Hubland, Wuerzburg, Germany; Department of Medicine II, Division of Gastroenterology, University of Wuerzburg, Wuerzburg, Germany; and Food Chemistry and Toxicology, Molecular Nutrition, University of Kaiserslautern, Erwin-Schroedinger-Strasse 52, 67663 Kaiserslautern, Germany