Comparative Evaluation of Total Phenolic Content and Antioxidant Capacity in Aronia melanocarpa, Crataegus orientalis spp, and Cornus mas L. fruits

This study comparatively evaluated the total phenolic content (TPC) and antioxidant capacity of three phenolic-rich fruit species: Aronia melanocarpa (cv. Nero and Viking), Crataegus orientalis (hawthorn), and Cornus mas (cv. Yalçınkaya 77). Fully mature fruits were harvested during the 2024 growing season and analyzed using standardized Folin–Ciocalteu and ABTS assays. The experiment was conducted in a completely randomized design, and data were analyzed by analysis of variance (ANOVA) followed by LSD mean separation. Highly significant species effects were detected (p < 0.001). Aronia cultivars exhibited markedly higher phytochemical richness, with TPC values of 2594.44 mg GAE 100 g⁻¹ FW for cv. Viking and 2397.58 mg GAE 100 g⁻¹ FW for cv. Nero, clearly exceeding those of hawthorn (847.71 mg GAE 100 g⁻¹ FW) and cornelian cherry (821.45 mg GAE 100 g⁻¹ FW). Antioxidant capacity followed a similar pattern, with Viking (80.26%) and Nero (78.33%) showing significantly greater ABTS•⁺ radical-scavenging activity than hawthorn (49.28%) and cornelian cherry (51.60%). A strong linear relationship between TPC and antioxidant capacity (R2 = 0.9996) indicates that phenolic compounds are the principal contributors to antioxidant behavior across species. Overall, the results highlight the relatively higher antioxidant potential of A. melanocarpa and confirm hawthorn and cornelian cherry as valuable natural sources of antioxidants for functional food and nutraceutical applications.