Structure elucidation of transformation products of toxic plant alkaloids in stored or processed foods

该研究项目旨在阐明食品污染物吡咯里西啶生物碱（PA）、托烷生物碱（TA）和秋水仙碱（COL）的潜在转化产物。这些有毒植物的生物碱产品可能在受污染的食品或原料的储存或进一步加工过程中产生。在此，该项目的重点是储存，热处理（烘焙）和微生物发酵对相关食品基质蜂蜜，面包和牛奶或酸奶中有毒生物碱PA，TA和COL的影响。具体而言，该项目旨在研究蜂蜜储存对PA-N-氧化物的影响，面包烘烤对TA的影响以及酸奶发酵对PA和COL的影响。为此，必须建立所需的分析方法，并从上述食品基质中制备人工污染样品。在蜂蜜储存期间或在烘焙面包和将牛奶发酵成酸奶的过程中，定期检查PA、TA和COL含量。在PA、TA和COL的初始含量预期降低的情况下，通过使用高分辨率质谱（LC QToF-HRMS）结合多变量数据分析对天然材料样品和产品样品进行非靶向分析，鉴定有毒生物碱的潜在转化产物。对天然生物碱化合物的降解以及转化产物的形成的影响通过工艺参数的变化来确定。最后，从PA，TA和COL确定的转化产物的可能形成途径进行了假设与所获得的数据。

The research project aims to elucidate potential transformation products of the food contaminats pyrrolizidine alkaloids (PA), tropane alkaloids (TA) and colchicine (COL). Products of these toxic plants alkaloids can arise during the storage or further processing of contaminated food or raw materials. Herein, the project focuses on the effects of storage, thermal processing (baking) and microbial fermentation on the toxic alkaloids PA, TA and COL in the relevant food matrices honey, bread and milk or yoghurt, respectively. In detail, the project aims to examine the effects of honey storing on PA-N-oxides, baking of bread on TA and fermentation of yogurt on PA and COL.For this, the required analytical methods have to be established, and artificially contaminated samples from the above mentiones food matrices have to be produced. The PA, TA and COL contents are examined at regular intervals during the storage of honey or during the process of baking bread and fermenting milk into yoghurt. In case of the expected decrease of the initial contents of PA, TA and COL, potential transformation products of the toxic alkaloids are identified by untargeted analysis of the native material samples and product samples, using high-resolution mass spectrometry (LC QToF-HRMS) combined with multivariate data analysis. Effects on the degradation of the native alkaloid compounds as well as the formation of transformation products are determined via a variation of process parameters. Finally, possible formation pathways of identified transformation products from PA, TA and COL are postulated with the obtained data .