臭氧降解污染小麦中呕吐毒素的效果及降解产物推测

Efficacy of Deoxynivalenol Detoxification by Ozone Treatment in Wheat and Prediction of Degradation Products

利用臭氧降解小麦中的呕吐毒素,通过超高效液相色谱-串联四极杆飞行时间质谱(ultra performance liquid chromatography quadrupole time-of-flight mass spectrometry,UPLC Q-TOF MS)测定了纯水体系中呕吐毒素的臭氧降解产物。结果表明:全麦粉中的呕吐毒素降解率显著高于小麦籽粒。当小麦水分含量为20.10%,臭氧质量浓度为100 mg/L,处理60 min后,呕吐毒素含量由3.89 mg/kg 降到了0.83 mg/kg。建立的一级动力学方程显示臭氧反应速率为k_(100 mg/L)>k_(75 mg/L)>k_(50 mg/L)>k_(25 mg/L)。根据UPLC Q-TOF MS得到离子碎片信息提出了可能的离子碎片生成途径并推测了臭氧降解产物结构,5种主要产物的m/z分别为344.948 1、329.205 0、311.191 8、311.190 7和346.240 4。

In this study, we used ozone to reduce deoxynivalenol（DON） in contaminated wheat, and the ozonation products were deduced using ultra performance liquid chromatography quadrupole time-of-flight mass spectrometry （UPLC Q-TOF MS）. The results showed that DON content in whole wheat flour decreased more quickly than in wheat kernels. For wheat with a moisture content of 20.10%, DON content was reduced from 3.89 mg/kg to 0.83 mg/kg after 100 mg/L ozone treatment for 60 min. The kinetic model constants with different ozone concentrations showed the decreasing order of k100 mg/L〉k75 mg/L〉k50 mg/L〉k25 mg/L, which was consistent with the experimental results. According to the mass spectral and ion fragmentation information from UPLC Q-TOF, possible ozonation products were proposed. The m/z of the major products were 344.948 1, 329.205 0, 311.191 8, 311.190 7 and 346.240 4, respectively.