Establishment Of A Method For Detection And Detoxification Of Alternaria Toxins In Feed

Alternaria toxins produced by Alternaria spp.are often found in feeds and raw mate-rials（corn,wheat,etc.）.Affected by environmental temperature,humidity,p H and other factors,it is easy to be polluted.Not only will it result in reduced crop yields,but feeding animals may also cause animal diseases and economic losses.What’s more,human con-sumption of livestock and poultry products contaminated with toxins can also cause food safety problems and harm human health.Therefore,it is important to detect and monitor the content of Alternaria toxins in feeds from the source and to use effective adsorbent to adsorb Alternaria toxins in feeds for the development of livestock and poultry farming industry.In this paper,the kinds of hazards of Alternaria toxins are summarized,and the pre-treatment techniques,detection methods and common detoxification methods of samples are introduced.Based on solid phase extraction technology,an UPLC-MS/MS analysis method was established to detect the content of six kinds of Alternaria toxins at the same time,and the adsorption mechanism of two different types of adsorbents on Alternaria tox-ins was studied.Specific research contents and results are as follows:（1）To establish a SPE-UPLC-MS/MS method for simultaneous determination of six kinds of streptomycin（AOH,AME,ATX-I,Te A and TEN）in feed.The feed samples were extracted twice by 1.0%acetonitrile formate（84+16）and purified by HLB extraction col-umn.Gradient elution was performed using Waters ACQUITY UPLC HSS T3 column with1 mmol NH₄HCO₃-H₂O solution（A）and CH₃OH（B）as mobile phases.The linear relation-ship of the method was good in the range of 1μg/L to 200μg/L,the correlation coefficients R² were all greater than 0.9995,the detection limits were 0.11μg/kg to 1.67μg/kg,and the limits of quantitation were 0.38μg/kg to 5.57μg/kg.At low,medium and high concentra-tions of 20μg/kg to 100μg/kg,the recoveries of the six targets ranged from 65.65%to117.36%,and RSD ranged from 2.55 to 8.29.The experimental results show that this method is simple,rapid,accurate and accurate for the detection of Alternaria mycotoxin in feed.（2）The adsorption mechanisms of 2 different types of adsorbents,montmorillonite（MMT）andβ-glucan（β-Dex）,on Alternaria toxins mycotoxins were investigated.After isothermal adsorption studies and kinetic studies,it was found that the adsorption of 6 Al-ternaria mycotoxin mycotoxins by the 2 adsorbents was more consistent with the Freun-dlich model,with R² values ranging from 0.9501 to 0.9988 for MMT and from 0.9685 to0.9976 forβ-Dex,and the use of MMT adsorbent was more favorable for the adsorption.The results of the fitting using adsorption kinetic model showed that the adsorption pro-cesses of both adsorbents were more consistent with the quasi-secondary reaction kinetic model,where the R² values of MMT ranged from 0891 to 0.9859 and the Q_e values ranged from 212.50 ng/mg to 1172.83 ng/mg;the R² values ofβ-Dex ranged from 08175 to 0.9954and the Q_e values ranged from 137.44 ng/mg to 1537.87 ng/mg.It indicates that the adsorp-tion occurs as two complex and integrated adsorption processes,surface adsorption and in-ternal diffusion,which are both physical and chemical adsorption.The effects of adsorbent dosing,time,temperature and p H on the adsorption of six Alternaria mycotoxin in feed by two adsorbents were investigated by single-factor experiments.The adsorption effect ofβ-Dex is slightly higher than that of MMT under the same dosage,adsorption time and ad-sorption p H,while the adsorption temperature of MMT is wider.Taken together,the adsorp-tion characteristics of the two adsorbents on the adsorption of the six Alternaria mycotoxin did not show significant differences,and the actual feed sample conditions explored also showed that the differences in the removal rates of Alternaria toxins between the two were small,and both could be practically applied in livestock breeding to reduce the interference of streptavidin,reduce the damage to animal bodies and maintain animal health.