Phytochemical Profiling and Biological Activities of Stachys cataonica Bhattacharjee et Hub.-Mor. Extracts: An...

The genus Stachys L. genus is in the Lamiaceae family; comprises many numerous medicinally important taxa traditionally used in Anatolia for nutritional and therapeutic purposes. Many Stachys taxa Stachys species have been employed in folk medicine for respiratory, gastrointestinal, inflammatory, metabolic, and skin disorders, as well as wound healing. Despite their recognized ethnopharmacological importance, the chemical composition and biological activities of several endemic Stachys taxa remain insufficiently characterized. Stachys cataonica Bhattacharjee et Hub.-Mor. is an endemic species of Türkiye, for which detailed ethnopharmacological information is limited. Therefore, this study aimed to investigate the biological activities and chemical composition of S. cataonica extracts and to provide a preliminary characterization of its bioactive compounds. Petroleum ether, chloroform, and methanol extracts of S. cataonica were prepared. These extracts were evaluated for antioxidant, antimicrobial, anticholinesterase, and anti-urease activities. An LC-MS/MS-based metabolite profiling approach was subsequently applied to characterize the chemical constituents of the bioactive methanolic extract. Among the tested extracts, the methanolic extract exhibited the strongest DPPH radical-scavenging activity (IC₅₀: 0.026 mg/mL), ferric reducing antioxidant power (FRAP: 4.741 mM FeSO₄ equivalents/mg extract), cupric ion-reducing antioxidant capacity (CUPRAC: 3.758 mM Trolox equivalents/mg extract), anti-urease activity (35.661% inhibition), and antimicrobial activity. Detailed phytochemical analysis revealed that verbascoside was the predominant annotated metabolite in the methanolic extract, accounting for 41.05% of the normalized peak area, followed by caffeic acid (16.71%) and 8,8'-methylenebiscatechin (8.63%), tentatively annotated as a methylene-linked flavan-3-ol dimer. These findings provide preliminary evidence of the bioactive potential of S. cataonica and highlight its methanolic extract as a rich source of phenolic and proanthocyanidin-related metabolites. The identified compounds may contribute to the observed biological activities and support further investigation of S. cataonica as a potential source of bioactive natural products with pharmacological and biotechnological applications. The metabolite profile obtained in this study expands the phytochemical knowledge of this endemic species and provides a basis for mechanistic and bioactivity-guided studies.