Labeled Fumonisins: Production and Use of Fumonisin B1 Containing Stable Isotopes

Abstract

Fumonisin B1 (FB1) labeled on the branch methyl groups with deuterium was produced in liquid cultures, and methyl-D3-labeled methionine was added. The isolated FB1 had 90% incorporation of 6 deuterium atoms and 9% incorporation of 3 deuterium atoms. The labeled FB1 was used as an internal standard for 2 analytical methods to measure FB1 in extracts of corn, corn products, and cultures. One method was hydrolysis followed by gas chromatography/mass spectrometry (GC/MS) of the derivatized backbone, and the other was analysis by fast atom bombardment MS (FAB/MS). Incorporation of labeled FB1 into samples resulted in a GC/MS method with improved precision and accuracy and allowed for a quantitative FAB/MS method.