Submitted to: Toxicologist
Publication Type: Abstract Only
Publication Acceptance Date: 1/15/2003
Publication Date: 3/1/2003
Citation: VOSS, K.A., NORRED, W.P., MEREDITH, F.I., RILEY, R.T., BACON, C.W., SAUNDERS, D.S. 2003. EFFECTS OF COOKING ON THE BIOLOGICAL ACTIVITY OF FUMONISINS. TOXICOLOGIST. v.77. Abstract p.252. Interpretive Summary: Abstract only
Technical Abstract: Fumonisin (FB) mycotoxins are found in corn and corn-based foods. Cooking decreases FB concentrations under some conditions, but little is known about how cooking effects its biological activity. Baked cornbread (BCB), pan-fried corn cakes (PFC), and deep fried corn fritters (DFF) were made from corn meal spiked with Fusarium verticillioides culture material (FCM) and fed to male rats (n=5) for 2 weeks at high (1% w/w FCM equivalents) or low (0.1 % FCM equivalents) doses. Controls were fed 1% w/w sound corn. Toxic response to BCB, PFC, DFF, and FCM included decreased body weight gain (1% diets only), decreased kidney weight, and microscopic kidney and liver lesions of the type caused by FB. FB concentration (FB1 + FB2) in the 1% w/w PFC diet (92.2 ppm) was slightly, but not significantly (p<0.05) lower than those of the 1% w/w BCB (132.2 ppm), DFF (120.3 ppm) and FCM (130.5 ppm) diets. In a second experiment, 10 g of corn, masa made from the corn, and tortilla chips made from the masa were extracted twice with 50 ml acetonitrile/water (1:1). Extracts were combined, dried, and redissolved in 1.0 ml DMSO. Vero cells were dosed with 4 ul of the redissolved extracts for 48 hr. The corn extract inhibited ceramide synthase as indicated by significantly increased cell sphinganine (Sa) concentrations (mean=132 pmole/well), whereas Sa was unaffected by the masa, baked chip and fried chip extracts (mean Sa 14-24 pmole/well). FB1 concentrations of the masa and chips (3.6-6.7 ug/g) were likewise reduced 80-90% compared to the corn (32 ug/g). In summary, baking and frying had no significant effect on the biological activity or concentration of FB in corn-based foods while, in contrast, nixtamalization reduced both biological activity and FB concentration in masa. Furthermore, these studies provided no evidence for the formation of unknown, biologically active FB during cooking.