Phytochemical Profile, Fatty Acid Composition, Mineral Content, and α-Amylase/α-Glucosidase Inhibitory Activities of Date Seed Extracts from Four Moroccan Varieties Grown in the Figuig Oasis

Date palm (Phoenix dactylifera L.) seeds, often discarded as by-products during date fruit processing, represent approximately 6–20% of the fruit’s mass depending on cultivar and maturity stage. Although traditionally used for producing activated charcoal and in environmental remediation, their pharmacological potential remains underexplored. This study aimed to evaluate the chemical composition, biological activity, and potential commercial value of seeds from four widely consumed Saharan cultivars (Assiane, Boufegouss, Aziza, and Majhoul) collected in the Figuig region. Soxhlet extraction was employed to obtain seed extracts, which were subsequently characterized by qualitative and quantitative phytochemical screening. The analyses revealed the presence of polyphenols, flavonoids, terpenoids, steroids, alkaloids, and other secondary metabolites. The Aziza and Boufegouss varieties were particularly rich in flavonoids (82.09–139.61 mg quercetin equivalents/100 g dry matter) and total polyphenols (69.81–1183.96 mg gallic acid equivalents/100 g dry matter). Mineral profiling confirmed the occurrence of essential trace elements, including Zn, Cu, Fe, and Co. To investigate their antidiabetic potential, in vitro assays of α-glucosidase and α-amylase inhibition were performed. Acetone extracts demonstrated significant inhibitory activity against both enzymes, suggesting a promising role of P. dactylifera seed extracts as natural agents for the management of type 2 diabetes mellitus.