|Kim, Eun Kyung|
Submitted to: Association of Official Analytical Chemists International Symposium
Publication Type: Abstract Only
Publication Acceptance Date: September 18, 2003
Publication Date: N/A
Technical Abstract: Corn silage is a popular feed source for growing ruminants. Several mycotoxins are known to exist in corn, raising the possibility they might survive ensiling and constitute a potential hazard to animals. Fumonisins are a structurally related group of water soluble mycotoxins mainly produced by Fusarium verticillioides (formerly F. moniliforme) and Fusarium proliferatum, and frequently contaminate corn. A liquid chromatography method for determining fumonisin B1, B2 and B3 in corn silage was developed. The corn silage was extracted with 0.1 M ethylenediaminetetraacetic acid (EDTA, tetra sodium salt), and the filtrate applied to a FumoniTest immunoaffinity column. Fumonisins were derivatized with naphthalene-2,3-dicarboxaldehyde (NDA), separated on a C18 LC column, and detected using fluorescence (excitation 268 nm, emission cutoff 470 nm). Under these conditions, retention times of fumonisins were 23.7 min for FB1, 42.9 min for FB3 and 45.2 min for FB2. The detection limits for FB1, FB2 and FB3 were 50, 25 and 25 ng/g, respectively. Recoveries of FB1, FB2 and FB3 from wet and dried corn silage spiked over the range of 100-5000 ng/g were 91-106%. The method was applied to corn silage samples collected from the Midwestern area of the United States. Of 89 corn silage samples, FB1, FB2 and FB3 were found in 86 (97%), 64 (72%) and 51 (57%) of samples. The mean positive levels of FB1, FB2 and FB3 were 615 ng/g, 93 ng/g and 51 ng/g, respectively.