Bioactive compounds analysis in food matrices and waste products

Food and nutrition research have grown exponentially over the past two decades, changing the way food is considered. In fact, it is no longer considered simply energy for the body but provides components with specific functions and nutritional properties, which include potential benefits, as well as possible harmful effects on health; among these, fatty acids, vitamins, phenolic acids, and flavonoids have been studied in recent years. In recent years, proteins, peptides and lipids have also played an important role in the study of components with high nutritional value, giving way to a new branch of the omic sciences, namely nutritional proteomics (nutriproteomics) and lipidomics. The study of bioactive peptides present in various food products represents a new field of research and field of application of proteomic analysis. Some peptides are able to trigger physiological activities that promote skin health, such as stimulating collagen synthesis, controlling angiogenesis and melanogenesis and modulating cell proliferation. Peptides are often classified as multifunctional peptides, i.e. they are capable of inducing more than one physiological activity. These characteristics make them suitable for use as therapeutic agents in the pharmaceutical field or as functional compounds, food additives, bio-preservatives in the field of nutraceuticals. These peptides can be released in different ways: they can be naturally present (i.e. endogenous) in matrices due to the presence of enzymes or bacteria, they can be released during gastrointestinal digestion, they can be formed following processes that occur in foods such as maturation, fermentation, storage or cooking, or by in vitro hydrolysis with the selection of a specific and appropriate enzyme. Except in the case in which the digestion is carried out in vitro by site-specific proteases, the obtained peptides can have a wide range of terminal amino acids and sizes. Of interest are both the bioactive peptides derived from enzymatic digestion, but also the short peptides naturally present within the matrix. Another very interesting class of molecules, not widely studied but specifically analyzed in this work are: seleno-amino acids. These compounds regulate many biological activities, and are important against various diseases. Another important goal is the study of waste. This type of product is normally seen as a problem for the economy and the environment, because it must be disposed of waste could be better used, though, not only as feed for animals but, for example, as a source of bioactive compounds. Therefore, the purpose of this doctoral project was to develop effective and innovative analytical strategies for the study of bioactive molecules and identification of compounds not abundant or not yet identified in different food matrices.