小麦中呕吐毒素臭氧降解机制及产物安全性评价

Deoxynivalenol (DON) is a common mycotoxin in grain and its strong toxicity, difficult degradation and high bioaccumulation can severely damage the health of human and animals. At present, the degradation methods of DON are of low efficiency, high costs and being easy to influence the quality of raw materials and difficult for industrialization application. This project is based on the ozone treatment efficiency on DON-polluted wheat in previous studies and it is found that this treatment has no influence on the quality of wheat powder, so it owns a bright application prospect. However, ozone degradation mechanism of DON is still not clear currently and there are few studies on the safety of degraded products. Thus, all these have been a bottleneck to the application to DON degradation in wheat.. This study plans to take DON in wheat as object and study DON degradation behaviors and degradation kinetics under the effects of ozone. Preparative liquid chromatography will be adopted to screen the degradation products of DON at each level in the ozone system and DON product structure and classification can be identified the dynamic changes of products can be traced by aid of mass spectroscopy and nuclear magnetic resonance so as to illustrate the detailed process and mechanism of the oxydative degradation of DON. Through Ames test and cytotoxicity model, the safety of ozone degradation products can be evaluated and new safe and effective DON degradation methods in wheat also will be explored and established. The implementation of this project aims at providing favorable theoretical guidance and practical basis for ozone-based DON degradation in grain.

呕吐毒素（DON）是粮食中常见真菌毒素，具有毒性强、降解难、生物蓄积性高等特征，严重危害人和动物的健康。目前DON降解方法效率低、成本高，容易影响原料品质，难以产业化应用。本项目基于前期研究臭氧处理DON污染小麦的有效性，且对小麦加工成粉的品质无影响，具有良好应用前景。但目前对DON臭氧降解机制尚不明确，也缺乏降解产物安全性研究，这成为其应用于降解DON污染小麦中的瓶颈。.本研究以小麦中DON为对象，研究臭氧作用下DON降解行为及降解动力学特征；采用液相制备色谱筛查DON在臭氧体系中的各级降解产物，并基于质谱和核磁共振技术鉴定DON产物结构及分类，追踪产物动态变化，阐明DON氧化降解的详细历程和机制；通过Ames试验和细胞毒性模型，评估DON臭氧降解产物安全性，探索和建立降解小麦中DON安全而有效的新方法。通过本项目的实施，以期为臭氧降解DON污染粮食提供良好的理论指导和实践依据。

呕吐毒素（Deoxynivalenol，DON）是真菌产生的一种次级代谢产物，能致畸、致突变，且具有极大的毒性。由于气候、储存条件等因素，小麦等粮食极易受DON污染。目前降解DON的方法主要有物理、化学及生物法三种。物理法降解毒素效率较低，化学法易残留，生物法成本较高。因此，寻找安全经济高效的DON降解方式非常必要。臭氧可自动分解成氧气，无残留，不会污染原料，本项目比较了臭氧降解不同体系中DON的效果，采用超高效液相色谱串联四级杆飞行时间质谱、核磁共振等分析了DON的臭氧降解产物，并阐明了产物的生成途径和降解机制，探究了臭氧对小麦中DON的降解效果，建立了相应的DON降解动力学模型，并通过体外体内毒性实验评价了DON降解产物安全性。该研究为臭氧降解DON的应用提供了理论和实践依据。