Evaluation of the Astragalus exscapus L. subsp. transsilvanicus Roots’ Chemical Profile, Phenolic Composition and Biological Activities

Novel and natural molecules for pharmaceutical applications are a contemporary preoccupation in science which prompts research in underexplored environments. Astragalus exscapus ssp. transsilvanicus (Schur) Nyár. (ASTRA) is a plant species endemic to Transylvania, having a very similar root system with that of A. membranaceus (Fisch.) Bunge, known for its health promoting properties. The present study endeavored to perform basic characterization of the ASTRA roots by proximate analysis, to investigate the fatty acid profile of the lipids extracted from the ASTRA roots, to examine the phenolic composition of the root extracts by liquid chromatography, and to evaluate the biological activities through determination of the antioxidant, antimicrobial and cytotoxic capacities of the extracts. The primary compounds found in the ASTRA roots were carbohydrates and lipids, and the fatty acid composition determined by GC-MS showed linoleic acid as preponderant compound with 31.10%, followed by palmitic, oleic and α-linolenic acids with 17.30%, 15.61% and 14.21%, respectively. The methanol extract of the ASTRA roots presented highest phenolic content, Astragaloside IV being the predominant compound with 425.32 ± 0.06 µg/g DW. The antimicrobial assay showed remarkable antimicrobial potential of the extract at a concentration of 0.356 and 0.703 mg ASTRA root powder (DW)/mL, highlighting its efficacy to inhibit S. aureus and S. epidermidis bacterial strains. Furthermore, the cell proliferation assessment showed the noteworthy proficiency of the treatment in inhibiting the proliferation of B16F10 melanoma cells.