Chemical Composition and Antioxidant, Anti-Inflammatory, and Enzyme Inhibitory Activities of an Endemic Species from Southern Algeria: Warionia saharae

Warionia saharae Benth. & Coss. (Asteraceae) is an endemic species of North Africa naturally grown in the southwest of the Algerian Sahara. In the present study, this species’ hydromethanolic leaf extract was investigated for its phenolic profile characterized by ultra-high-performance liquid chromatography coupled with a diode array detector and an electrospray mass spectrometer (UHPLC-DAD-ESI/MS). Additionally, the chemical composition of W. saharae was analyzed by gas chromatography–mass spectrometry, and its antioxidant potential was assessed through five in vitro tests: DPPH(●) scavenging activity, ABTS(●+) scavenging assay, galvinoxyl scavenging activity, ferric reducing power (FRP), and cupric reducing antioxidant capacity. The UHPLC-DAD-ESI/MS analysis allowed the detection and quantification of 22 compounds, with taxifolin as the dominant compound. The GC–MS analysis allowed the identification of 37 compounds, and the antioxidant activity data indicate that W. saharae extract has a very high capacity to capture radicals due to its richness in compounds with antioxidant capacity. The extract also showed potent α-glucosidase inhibition as well as a good anti-inflammatory activity. However, weak anti-α-amylase and anticholinesterase activities were recorded. Moreover, an in silico docking study was performed to highlight possible interactions between three significant compounds identified in W. saharae extract and α-glucosidase enzyme.