Evaluation of Bioactive Properties of Ultrasound-Assisted Extracts from Prokupac Grape Skins for Functional Foods

The phenolic compounds present in wine industry by-products are a valuable source of biologically active ingredients that could be used in the development of functional foods. This manuscript investigates the potential of ultrasound-assisted extracts from Prokupac grape skins-a wine industry by-product-as functional food ingredients. Four extracts were prepared using different solvents and evaluated for their antioxidant, anti-inflammatory, and antimicrobial properties. Antioxidant activity was assessed through DPPH, ABTS, and FRAP assays, as well as EPR spectroscopy. Phenolic composition was determined via HPLC analysis, and anti-inflammatory potential was evaluated using a lipoxygenase inhibition assay. Results indicated that the extracts PSE3 (ethyl acetate) and PSE0 (direct extraction with 50% ethanol) exhibited superior antioxidant and anti-inflammatory activities, which can be attributed to their high polyphenolic content. Additionally, the extracts demonstrated antimicrobial effects against the tested microorganisms. These findings suggest that Prokupac grape skin extracts, particularly PSE3 and PSE0, could be valuable additions to functional foods, offering health benefits through their bioactive properties.