Effet chez le porcelet d'une exposition à un régime co-contaminé en ...

INTRODUCTION4) Hydrogen peroxide/sodium bicarbonateAs mentioned above, the addition of oxidizing agents, such as hydrogen peroxide, is an effectivehelp in nixtamalization. Some studies have shown that hydrogen peroxide/sodium bicarbonate aloneis effective for simultaneous degradation/detoxification of aflatoxins and fumonisins, therebyreducing toxicity (Lopez-Garcia et al., 1999).Abd Alla (1997) investigated the efficiency of hydrogen peroxide for detoxification ofcontaminated corn with zearalenone. A degradation level of 84% was achieved with a treatmentwith 10% H 2 O 2 for 16 hours at 80 0 C.5) Sodium bisulfiteThe use of sodium bisulfite as a detoxification reagent is worth special mention as it is a commonfood additive. In maize, sodium bisulfite treatments used at 0.5% and 2% destroy 80% and 90% ofaflatoxin B1 respectively (Doyle et al., 1982). The main product of reaction is a sulfonate, AFB1-S,formed by addition of bisulfite to the furan ring present in AFB1 and AFG1, but not in AFB2 and AFG2.Piva et al. (1995) considered that although this process is less efficient than ammoniation, itovercomes some of the typical disadvantages of ammonia method (less hazardous to handle for thestaff, no undesirable brown color of treated feed or no impact on nutrient value) and is muchcheaper.Sodium bisulfite also destroys deoxynivalenol in maize. Indeed, Young et al. (1987) reported thatDON in contaminated maize was reduced by 85% through treatment with sodium bisulfite solutions.The greatest reductions (up to 95%) were achieved when the contaminated corn was autoclaved for1h at 121°C in the presence of 8.33% aqueous sodium bisulfite. In the same study, the authorsperformed two toxicological trials in order to assess the safety of this process; the first one consistedto a 7 days feeding trial in pigs with treated-contaminated corn (7.2 ppm DON), and the second onewith DON-sulfonate (the by-product obtained after treatment) which was administered orally toswine at the same level (molar equivalent) at which nonderivatized DON caused severe emesis (seeTable 7). However, some authors indicated that DON-sulfonate is stable in acid but hydrolyzed toDON under alkaline conditions.6) Reducing sugarsThe primary amine group in the fumonisin B1 molecule is responsible for its toxicity (Fernandez-Surumay et al., 2004). Transformation of FB1 into a FB1-reducing sugar adduct through anonenzymatic browning reaction (65 °C for 48 h) reduces significantly the toxicity of the native FB165