Titolo della tesi: Lipidomic Profiling and Bioactivity Evaluation in Complex Matrices.
The work reported in the present PhD thesis is based on the evaluation of the lipidomic profile in several matrices. The aim of the thesis was to establish an analytical platform for the investigation and identification of polar lipids, ranging from sample preparation to lipids identification. First of all, the optimization of chromatographic and mass spectrometric conditions, by applying reversed phase liquid chromatography coupled with high resolution mass spectrometry, was performed. Moreover, the attention was focused on two poorly characterized polar lipid classes in spirulina microalgae, namely glycerophospholipids and sulfolipids. In addition, Lipostar, one of the most comprehensive lipidomic software tool, was implemented to extend the lipid class coverage for sulfolipids. Subsequently, an enrichment method, as selective as possible for these two main lipid classes, was developed by comparing two solid phase extraction, namely graphitized carbon black (GCB) and weak anion exchange (WAX). The final protocol was applied on several matrices i.e. spirulina microalgae, extra virgin olive oil and Cannabis sativa. The last part of the thesis describes the work undertaken during the period abroad. The analytical investigation was enlarged, by evaluating the applicability of supercritical fluid chromatography hyphenated to high resolution mass spectrometry to separate the most representative plasma metabolites with a wide range of polarity. In conclusion, the optimized protocol was applied to plasma samples.