Untargeted Metabolomic Profiling and Bioactivity Insights into Alkanna corcyrensis

This study aimed to characterize the chemical composition and evaluate the biological activities of the aerial parts of Alkanna corcyrensis Hayek (AC), an endemic Greek species not previously studied. Phytochemical analysis of the methanolic extract was performed using UHPLC-ESI-Q-TOF–MS/MS combined with molecular networking analysis. Additionally, the total phenolic content (TPC) and total flavonoid content (TFC) were determined. Chromatographic separations were carried out to isolate major compounds, and the antioxidant capacity, along with enzyme inhibitory activity, was assessed. The analysis led to the tentative identification of 86 compounds, including 67 phenolic compounds (mainly caffeic acid derivatives and flavonoid glycosides), 10 pyrrolizidine alkaloids of trachelanthamidine, platynecine, and retronecine types, and nine organic and fatty acid derivatives. Among these, one flavonol glycoside (kaempferol-O-malonyl methyl ester hexoside) and three pyrrolizidine alkaloids (9-sarracinoyl-trachelanthamidine/isoretronecanol, retronecine-pentoside, and trachelanthamidine/isoretronecanol-hexoside) were reported for the first time. The extract exhibited high TPC (74.45 mg GAE/g extract) and TFC (46.66 mg GAE/g extract). Chromatographic separations resulted in the isolation of five major metabolites, namely rosmarinic acid, danshensu, kaempferol-3-O-glucoside, kaempferol-3-O-galactoside, and quercetin-3-O-glycoside. Biological evaluation revealed considerable antioxidant activity and inhibitory effects against α-glucosidase (6.65 mmol ACAE/g extract). Overall, this study highlights the remarkable phytochemical diversity and richness of AC among alkanet species and demonstrates its promising antioxidant potential, laying the foundation for further investigations towards its future exploitation.