EXPLORING THE HIGH THROUGHPUT POTENTIAL OF MICROEXTRACTION TECHNIQUES FOR THE ISOLATION OF LOW-MOLECULAR WEIGHT POLYPHENOLS IN DIFFERENT FOOD MATRICES

Polyphenols are widespread constituents of several foods matrices, including fruits, vegetables, cereals, olive and legumes, juices and beverages such as tea, coffee, beer and wine. Despite their wide distribution, the health effects of dietary polyphenols have come to the attention of nutritionists namely in recent years. The preventive effects of these secondary plant metabolites in terms of cardiovascular, neurodegenerative diseases and cancer are deduced from epidemiologic data as well as in vitro and in vivo studies. The selection of the proper analytical strategy for studying phenolics in food matrices depends on the purpose of the study as well as the nature of the sample and the target analyte. Conventional extraction techniques, as solid-phase extraction andor liquid-liquid extraction, represented for long time the gold standard for sample preparation. However, during the last decade, downstream analytical procedures evolved very significantly, making sample preparation a serious bottleneck in the analytical workflow. In this sense, extraction and characterization of dietary polyphenols will be explored as a case study to demonstrate how modern microextraction strategies solutions, as MEPS, m-SPEed and m-QuEChERS, are fostering the whole analytical workflow and performance. The potentialities of new sorbents and nanomaterials tailored for microextration of specific compounds will be also addressed.