44G-22 |
Efficacy and safety evaluation of ozone to degrade aflatoxin in corn |
A. D. PRUDENTE, JR. and J. M. King. Department of Food Science, Louisiana State University Agricultural Center, 111 Food Science Bldg., Louisiana State University, Baton Rouge, LA 70803 The presence of aflatoxins in food and feeds pose serious problems in human and animal health. Aflatoxin B1, the most potent of four naturally occurring aflatoxins, is both hepatotoxic and carcinogenic. Ozonation, a physical/chemical oxidation method, has been recently developed for the decontamination of aflatoxins in grains. This study aimed to determine the safety and efficacy of the ozonation procedure to reduce aflatoxin hazards in corn. Clean and contaminated corns were treated with ozone (10-12 wt%) at a rate of 2L/min for 96hrs. Permanency of the decontamination process was evaluated by exposing ozonated samples to acidic condition. Extraction and quantitation of aflatoxins followed the AOAC Multifunctional column method. Mutagenic potential of the extracts were evaluated by Ames assay using TA98 and TA100 strains. Fatty acid composition was determined by GC. Results showed that ozone reduced the level of AFB1 from 586 ppb to 47 ppb and no reversion to parent compound was observed. Extracts, with and without hexane clean-up, failed to show mutagenic potential in the Ames assay compared to pure AFB1. But further clean-up using Mycosep column increased the mutagenicity of the extracts. This indicated that anti-mutagen compounds in corn inhibited the mutagenicity of extracts. This was confirmed when mutagenicity of AFB1+hexane extracts were lower in contrast with AFB1, but hexane extracts from ozonated corn had less inhibitory effect than from non-ozonated corn. This suggested that either ozone destroyed anti-mutagens in corn or toxic products were formed from ozone-aflatoxin reaction. Changes in levels of fatty acids were observed after ozonation. Unsaturated fatty acids were oxidized to a greater extent in contaminated corn than in clean corn. Reductions were 0.5% and 3.4% for clean and contaminated corn, respectively. This study indicated the effectiveness of ozone in decontaminating AFB1 in corn. Further study should be done to evaluate the ozone-aflatoxin reaction products.
Session 44G, Toxicology & Safety Evaluation
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