ANTIOXIDANT, ANTI-INFLAMMATORY, AND BIOLOGICAL PROPERTIES OF HYDROALCOHOLIC EXTRACTS FROM CYDONIA OBLONGA AND MELA ROSA MARCHIGIANA PULP CALLUS

In this doctoral thesis, we investigated some biological activities and protective potentialities of hydroalcoholic extracts derived from the fruit pulp calluses of two apple varieties, namely Cydonia oblonga and Mela Rosa Marchigiana. Callus culture, an innovative method for generating secondary metabolites (SMs) from plant material, served as the basis for this investigation. Antioxidant activities were assessed using chemical methods such as DPPH, ABTS, and ORAC assays. Additionally, the evaluation involved quantifying the production of reactive oxygen species (ROS) in the hydrogen peroxide and tert-butyl hydroperoxide (TBHP)-injured human keratinocyte (HaCaT) cell line. The functional activities of the callus extracts were explored in murine macrophage (RAW 264.7) and HaCaT cell lines. Specifically, anti-inflammatory activity was examined in lipopolysaccharides (LPS)-treated RAW 264.7 cells through the Griess test. In LPS-treated HaCaT human keratinocytes, the study focused on the expression of genes associated with the oxidative stress and the inflammatory process, including Heme Oxygenase-1 (HO-1), inducible Nitric Oxide Synthase (iNOS), Interleukin-6 (IL-6), Interleukin-1 beta (IL-1β), inhibitor kappa B-alpha (ikBα) and Intercellular Adhesion Molecule (ICAM). With Mela Rosa Marchigiana callus extract it was applied a transition toward a system that mimics an in vitro gastrointestinal digestion for a more accurate and complex representation of physiological dynamics. In addition to the aforementioned activities, extracts from Cydonia oblonga and Mela Rosa Marchigiana calluses exhibited inhibitory effects on the activity of α-glucosidase, α-amylase, and lipase enzymes. The results presented in this thesis indicate that both Cydonia oblonga and Mela Rosa Marchigiana callus hydroalcoholic extracts possess anti-inflammatory, antioxidant activities both tested in cell-free and cell-based models and can downregulate the activity of digestive key enzymes involved in carbohydrate and lipid metabolism. These findings suggest their potential application in delaying and preventing acute or chronic diseases associated with aging, a physiological state in which oxidation and inflammation play a primary role. Finally, this work holds significance for the future development of a nutraceutical approach to managing hyperglycemia and dyslipidemia.