Polyphenolic Characterization, Antioxidant and Antihyperglycemic Activities of Crataegus spp. Fruit Extracts.

Crataegus L. (Rosaceae) comprises several species rich in nutrients and bioactive compounds with nutraceutical relevance. The present study aimed to investigate the polyphenolic profile, antioxidant activity, and in vitro antihyperglycemic-related activity of fruits from 11 Crataegus taxa collected in Western Sicily, a region characterized by a high diversity of this genus. Total polyphenol quantification indicated that, among the tested extracts, Crataegus laciniata exhibited the highest content (25.54 mg GAE/g). Using high-resolution Orbitrap Q-Exactive PLUS ESI-MS instrument (Thermo Fisher Scientific, Waltham, MA, USA), a comprehensive phytochemical characterization was performed. Hyperoside quantification revealed that Crataegus aff. insengae, Crataegus zichichii, and Crataegus drepanensis are rich in this bioactive compound (1.47, 1.22, 1.22 mg/g DW). Multivariate analysis, including principal component analysis (PCA), highlighted hyperoside and vitexin as the main contributors to sample differentiation. Additionally, Crataegus laciniata, Crataegus drepanensis, and Crataegus aff. insengae showed the highest antioxidant activity in chemical assays (DPPH, ABTS, and FRAP) and in Caco-2 and H9c2 cell models through the modulation of intracellular reactive oxygen species (ROS). Regarding antihyperglycemic-related activity, Crataegus laciniata, Crataegus azarolus var. azarolus, and Crataegus drepanensis extracts showed the best inhibitory activity against α-glucosidase and α-amylase. Overall, the study highlights the value of Crataegus fruits as sources of bioactive compounds for food and nutraceutical research and supports their further valorization.