Liquid Chromatographic Determination of Fumonisins B1 and B2 in Corn and Corn Products

Abstract

A liquid chromatographic (LC) method is described for determining fumonisin B1 (FB1) and fumonisin B2 (FB2), metabolites of Fusarium moniliforme, in corn and corn products. The metabolites are extracted with methanol-water (3 + 1), and the extract is added to a disposable strong anion exchange column. After the FB1 and FB2 are eluted from the column with methanol-acetic acid (199-1-1) and the eluate is evaporated to dryness, the metabolites are derivatized with o-phthaldialdehyde and 2- mercaptoethanol to make highly fluorescent derivatives. Reversed-phase LC with fluorescence detection is used for the final separation and determination. The estimated limit of quantitation is 10 ng/g for each metabolite. The average recoveries from corn were 67% for FB1 and 71% for FB2, with relative standard deviations of 5% for FB1 and 3% for FB2. The identities of the fumonisins were confirmed by mass spectrometry. Applications of the method include the analyses of corn meal and breakfast cereals.