Innovaciones en plataformas analíticas empleando estrategias metabolómicas para la determinación de micotoxinas y otros contaminantes en muestras biológicas y alimentos

Abstract

Metabolomics consists of an exhaustive and quantitative analysis of all metabolites in a system, metabolites being those molecules with a molecular mass of less than 1500 Da. The applications of metabolomics to food analysis are known as "foodomics”, a science that allow the monitoring of changes in food composition in terms of compositional analysis, food safety, food classification and traceability. The development of efficient methods that allow a reliable assessment of hazardous substances or components that may endanger the safety and quality of food has recently been a major challenge in the field of analytical chemistry. In this sense, foodomics has established itself as a recognized discipline to raise and ensure food safety standards, highlighting its applications in the control of mycotoxins in food. Mycotoxins are toxic compounds resulting from the secondary metabolism of several filamentous fungi, mainly Fusarium, Aspergillus, Penicillium and Alternaria species. These compounds can occur naturally in cereals, nuts, spices, cocoa, coffee, fruits and vegetables susceptible to fungal contamination, affecting the health of humans and animals. Therefore, their levels in food are strictly restricted by European legislation. However, there is a group of mycotoxins known as emerging mycotoxins, for which there is no established legislation, and it is of great importance to provide studies on their occurrence in order to facilitate their future legislation. Considering the low concentration levels at which these toxins are found and the matrix effect due to the samples, it is essential to develop new analytical methods of high sensitivity and selectivity. Sample treatment is a crucial step in the development of an analytical method. For this reason, research in the field of analytical chemistry has recently focused on the development of miniaturized sample preparation techniques. These techniques are jointly aimed at achieving preconcentration of the analytes of interest and simplifying the matrix, which is in line with the principles of Green Analytical Chemistry. Microextraction techniques arise from the development of miniaturized techniques that allow the extraction and preconcentration of analytes. In these techniques, the quantities of extractant phase used are of the order of micrograms or microliters, depending on whether they take place in solid or liquid phase. In this Doctoral Thesis, miniaturized sample treatments have been developed for the control of mycotoxins, mainly emerging mycotoxins, in samples little explored to date, including paprika, pâté and animal feed samples. Another significant objective within the field of metabolomics and foodomics is the exploration of bioactive compounds. Therefore, in this PhD Thesis, targeted and untargeted strategies have allowed to evaluate the metabolization of propyl propane thiosulfonate (PTSO), and the behavior of other bioactive compounds present in citrus and avocado. Finally, foodomics is used as a tool to establish similarities and differences between food products, thus providing essential information on the sensory and nutritional properties of foods, as well as to determine the spectral fingerprint and authenticity of the same. In this sense, in the last chapters of this Thesis, foodomics strategies have been applied for the monitoring of volatile organic compounds to study and establish the quality of certain foods such as olive oil or honey. For this purpose, detectors such as MS or ion mobility spectrometry (IMS) have been coupled to GC using headspace injection (HS) to minimize sample treatment, allowing the characterization of the profile of volatile organic compounds with high selectivity and sensitivity.