Tutor

The present Ph. D. thesis is focused on the characterization of unusual aminoacidic derivatives (-glutamyl amino acids, lactoyl amino acids, pyroglutamyl amino acids), collectively named Non Proteolytic Aminoacyl Derivatives (NPADs), present in Parmigiano Reggiano cheese, considering in particular their structural characterization, the origin and biological-functional properties. After a general introduction concerning cheese peptidomics approaches, bioactive peptides, peptides synthesis/analysis and previous results about NPADs, the first part deals with the use of NPADs as a marker of cheese ripening, through appropriate statistical analysis. The enzymatic production and degradation of NPADs are then examined in depth in the third chapter, indicating which enzymes in cheese might be responsible for their production and eventual degradation. Also bioaccessibility was evaluated, demonstrating the resistance of NPADs to gastrointestinal digestion and blood serum. Also the bioavailability of -Glutamyl-Phenylalanine, the most important representative of NPADs, was studied using Caco-2 model. The last part reports the first studies about the immunomodulatory and antioxidant properties of NPADs