46I-7 |
Liquid chromatographic method for moniliformin determination in corn tortillas and fate of the mycotoxin during corn tortilla processing |
A. CAPUTO, Food Science and Nutrition, Chapman University, One University Drive, Orange, CA 92866 and C. Munimbazi. Moniliformin is a fungal metabolite produced by many Fusarium molds, which commonly contaminate cereal grains including corn. The metabolite is acutely toxic to many animals and some scientists suggested that the toxin might be an etiological factor in a heart disease called Keshan Disease. Many analytical methods for moniliformin determination in cereal grains have been developed. However, no suitable analytical method for moniliformin determination in heat-processed corn-based products such as corn tortillas is available. The objective of this study was to develop an analytical method for moniliformin determination in corn tortillas and to study the fate of the toxin during simulated corn tortilla processing. Moniliformin was effectively extracted and ion-paired in a mixture of acetronitrile and 1% tetrabutylammonium hydrogen sulfate solution (30:70). Paired moniliformin was partitioned into dichloromethane, which was evaporated to near dryness. The residue was dissolved in HPLC-grade water and purified on SAX solid-phase extraction column. The toxin was separated from co-extracted impurities by ion-pair reversed-phase chromatography and determined by UV measurement at 229 nm. Recovery rates ranged from 76 to 100% for 0.025 to 1 µg/g of added moniliformin. The developed method was used to determine moniliformin in 14 samples of commercially available corn tortillas. Results showed that 12 samples contained detectable amounts of moniliformin ranging from 0.022 µg/g to 0.1 µg/g. The fate of moniliformin during simulated corn tortilla processing was studied. Analysis of moniliformin before and after the processing indicated a 70% decrease in moniliformin concentration in processed tortillas. Results from this study indicated that, although corn tortillas processing decreased significantly moniliformin content in finished product, it is still possible to detect the toxin in commercially available products.
Session 46I, Toxicology & Safety Evaluation
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