| The mold contamination of animal feed is very common because feeds can provideexisting environment for molds. The molds will produce mycotoxins, which are usuallydiffused by contaminated feeds and persist to exist in these feeds. Mold will bring twokinds of endangerment to the contaminated feed. One is feed deterioration caused by mold,and the other is animal intoxication caused by mycotoxins. Mycotoxins in animal feed mayalso bring harm to human health through food chain. Mold contamination will reduceutilization value of feed, even made the commercial value of feed lost completely. Thesevere problem of mold contamination has caused huge economy loss to feed industry.Research on moldy feed treatment is very popular nowadays, which helps combatfeed poison and anti-nourishment factors. There are several methods for detoxifying moldyfeed, among them are chemical methods (usually treating moldy feed with sodium hydrate,ammonia, sodium hypochlorite, chlorine), microbial degradation methods, enzymedegradation methods and physical adsorption methods.This study was focused on mechanisms of detoxification of a mycotoxin antidote,which was a new product developed in the research group.1. Test of adsorbent capability of the feed mycotoxin antidoteThe experiment evaluated detoxication efficiency of the mycotoxin antidote. AFB1adsorbing capacity of antidote SAL was evaluated by ELISA.①AFB1 adsorbing rate to SAL was 95.48%;②When concentration of SAL was between 300-500 ppm, aflatoxin B1 detoxifyingefficiency of SAL enhanced with increasing SAL concentration. When SAL concentrationwas above 500 ppm, the detoxification efficiency was no longer improved.2. Function mechanism of the feed mycotoxins antidoteThe experiment was conducted to study the adsorption area and adsorption mechanism of feed mycotoxin antidote SAL prepared with glycol or Grant method. The experimentgave the following results.①The maximum adsorption area of antidote SAL was 872 m2/g.②The A G of the antidote was -33.2 kJ/mol, the A Hads was -42.6 kJ/mol. Referring tothe research by Stumm (1992) and Gu (1994), we could designate the types of antidote'sadsorption according to the free energy change(△G) and adsorption entropy change (△Hads).△G=0 characterized a physical adsorption, so△G＞0 meant a chemical adsorption.△Hads＜20kJ/mol characterized a physical adsorption while△Hads＞20 kJ/tool reflected a chemicaladsorption. For reasons given above, the mechanism of mycotoxin adsorption to antidote isdesignated as "charge receptor" mediated physical adsorption.3. Ultra-Microstructure analysis of SALMolecular (or crystal) structures of SAL were compared with regular materials and thefollowing results were reached.①Molecular structure of SAL was porous while the regular material was usuallyspheroid and solid. The pore size was uniform, regardless of the size of SAL.②Area of inside surface of SAL was much bigger than the outer surface area, so insidesurface was efficiency deciding in detoxification.③According to chemical composition, detoxification function of SAL depended on"the electron accepter adsorption mechanism"4. The effect of Shenweijig on the vitaminsAbsorptive capacity of Shenweijing to OTA was measured with HPLC. Effect of Vc and Ve onabsorptive ability of Shenweijing to OTA was also analyzed. The study showed that Shenweijing owns aconsiderable capacity of absorption to OTA, the amount of which to be absorbed has a positivelinearized relationship with OTA concentration. The study also showed that the absorptive capacity ofShenweijing to OTA was not influenced by Vc or Ve. The absorption of Shenweijing to OTA is selective in nature.5. Application to broiler production900 AA broilers of 1 day old were selected to determine the effect of SAL onproduction efficiency.①Aflatoxin B1 could reduce the growth rate and feed conversion rate of broilerssignificantly. Adding SAL to feed could alleviate negative effects of aflatxion on weightgain and feed transform rate.②The amount of aflatoxin B1 in broiler liver would increase when the amount or timeof aflatoxin B1 in feed increased. Adding SAL into the feed could reduce the accumulationof aflatoxin B1 in the liver but could not make a complete clearance.6. Application to pig production180 hybrid pigs of 30 day old were selected to determine the effect of SAL on pigproduction. The following were main results.①Aflatoxin could significantly reduce food intake and growth rate of the animals.Aflatoxin could also reduce feed conversion rate.②SAL in pig feed could alleviate or remove the negative effects of mycotoxins on dailygain and feed conversion rate. It was also found that SAL could improve the weight gainand feed conversion efficiency significantly.
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