Author
Voss, Kenneth | |
RYU, DOJIN - University Of Idaho | |
JACKSON, LAUREN - Us Food & Drug Administration (FDA) | |
Riley, Ronald | |
GELINEAU-VAN WAES, JANEE - Creighton University |
Submitted to: Journal of Agricultural and Food Chemistry
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 1/27/2017 Publication Date: 8/23/2017 Citation: Voss, K.A., Ryu, D., Jackson, L., Riley, R.T., Gelineau-Van Waes, J. 2017. Reduction of fumonisin toxicity by extrusion and nixtamalization (Alkaline Cooking). Journal of Agricultural and Food Chemistry. 65:7088-7096. DOI: 10.1021/acs.jafc.6b05761. Interpretive Summary: Fumonisin B1 and other fumonisins are fungal toxins found in corn and corn-based foods. They are toxic to animals, cause cancer in rodents, and neural tube defects in mice. Reducing their concentrations in corn-based foods is therefore desirable. The effectiveness of two commonly used cooking methods, extrusion and nixtamalization (alkaline cooking method for making masa and tortillas) was therefore tested by means of bioassays. Rats were fed fumonisin contaminated corn before or after cooking by extrusion, extrusion with sugar supplementation, or nixtamalization. A third bioassay compared the developmental toxicity of fumonisin B1 and its degradation product, hydrolyzed fumonisin B1 when given to pregnant mice. Cooking by extrusion and nixtamalization reduced toxicity and the effectiveness of extrusion improved with the sugar supplementation. In the mouse bioassay, fumonisin B1 caused serious birth defects known as neural tube defects in the fetuses whereas no neural tube defects were found in fetuses of mice exposed to hydrolyzed fumonisin B1. Together these findings show that the toxicity of fumonisins in corn is reduced when the corn is cooked by extrusion or nixtamalization. Technical Abstract: Fumonisins are found in corn. They are toxic to animals, cause cancer in rodents, and neural tube defects in LM/Bc mice. Reducing their concentrations in corn-based foods is therefore desirable. Chemical analysis or in vitro bioassays of food extracts might not detect toxic fumonisin reaction products that are unknown or unextractable from food matrices, thus potentially underestimating in vivo toxicity. The effectiveness of two common cooking methods, extrusion (with and without sugar supplementation) and nixtamalization (alkaline cooking), to reduce the toxicity of fumonisin contaminated corn grits (extrusion) and whole kernel corn (nixtamalization) was demonstrated by means of rat feeding bioassays using fumonisin-specific kidney biochemical and pathological effects as indicators of potential toxicity. A third bioassay showed that in contrast to fumonisin B1 (FB1), hydrolyzed fumonisin B1 (HFB1: formed from FB1 during nixtamalization) did not cause neural tube defects when administered to LM/Bc mice. The findings indicate that both extrusion (without and more effectively with sugar supplementation) and nixtamalization effectively reduce the potential toxicity of FB1 contaminated corn. |