Phytochemical Markers of Cydonia oblonga Mill. Cultivars of Ukrainian Breeding

Abstract

Quince (Cydonia oblonga Mill.), one of the earliest domesticated fruit crops, combines high adaptability with stable productivity, making it a promising source of bioactive compounds. This study aimed to compare three Ukrainian quince cultivars (Maria, Darunok Onuku, and Kharkivska) with respect to their total flavonoid content and antioxidant activity in fruit extracts. The plants were grown in 2024 at the M.M. Gryshko National Botanical Garden of the National Academy of Sciences of Ukraine (Kyiv). Total flavonoid content was determined spectrophotometrically using the reaction with AlCl₃. The antioxidant activity of the extracts was determined by the 2,2-diphenyl-1-picrylhydrazyl free radical assay. Significant differences in total flavonoid content were observed among the studied cultivars, ranging from 1.19 ±0.08 to 2.48 ±0.07 mg RE g⁻¹ fresh weight, with the highest values recorded in cv. Maria. Antioxidant activity, assessed using EC₅₀ values, also varied among cultivars and followed a similar pattern. The lowest EC₅₀ value (18.49 ±1.6 mg) was observed for cv. Maria, indicating the highest antioxidant capacity, whereas higher values were obtained for cv. Kharkivska (20.59 ±1.8 mg) and cv. Darunok Onuku (23.68 ±1.8 mg). A clear relationship between flavonoid content and antioxidant activity was observed. Since all cultivars were grown under identical conditions, the detected differences can be attributed primarily to genotypic variation. The results highlight the potential of the studied cultivars, particularly cv. Maria is a promising source of natural antioxidants for use in food and nutraceutical applications.