Phytochemical Composition and Antimicrobial and Antioxidant Activity of Hedysarum semenowii (Fabaceae)

This paper provides a comprehensive phytochemical analysis of extracts obtained from the leaves and roots of Hedysarum semenowii using HPLC/PDA-ESI-QToF/MS-MS techniques. The study identified 53 compounds, with flavones and isoflavones as the primary polyphenols. Notably, flavones were predominant in the leaves, while isoflavones were found mainly in the roots, potentially serving as chemotaxonomic markers. Medicarpin and its glucoside were confirmed in the roots, while mangiferin and its derivatives were identified for the first time in both the roots and leaves. Isoflavones like formononetin, calycosin, and afrormosin, along with their glucosides, were exclusive to the roots. Flavonols such as quercetin and its glycosides were abundant in the aboveground parts. Our study also identified flavones like luteolin, flavanones (naringenin), and chalcones (liquiritigenin) in various parts. Additionally, the phenolic acids gallic and ferulic acids, as well as the organic acids malic and citric acid, were also detected. The extracts demonstrated differential antimicrobial and antifungal activities in a microbroth dilution assay, with the aerial part extracts showing superior efficacy, particularly against Staphylococcus epidermidis and Pseudomonas aeruginosa. Both aerial and underground parts exhibited comparable antifungal activity against Candida species. Antioxidant activity in the 1,1-diphenyl-2-picrylhydrazyl (DPPH^•) radical scavenging test varied significantly, with ethanolic extracts from the aerial parts showing the highest potential (Antioxidant Activity Index (AAI) 2.07 ± 0.13). In contrast, root extracts had consistently low antioxidant activity. The results highlight the aerial parts of H. semenowii as a more promising source of biologically active compounds with antimicrobial and antioxidant properties compared to the roots.