Phytochemical profile and bioactivities of hydroethanolic extracts of Pteleopsis suberosa and Piliostigma thonningii used in traditional medicine in Togo.

The increasing prevalence of multidrug-resistant pathogens has intensified the search for alternative sources of bioactive compounds. This study evaluated the antimicrobial and antioxidant potential of Pteleopsis suberosa and Piliostigma thonningii, two medicinal plants traditionally used in Togo to treat vaginal, respiratory, gastrointestinal, and skin infections. Hydroethanolic extracts from different plant organs were prepared by cold maceration. Phytochemical screening was performed using standard qualitative tests, while total flavonoid content was determined spectrophotometrically. Antioxidant activity was assessed using the phosphomolybdate reduction and ferric reducing antioxidant power (FRAP) assays. Antimicrobial activity was evaluated by agar well diffusion and broth microdilution methods. The highest extraction yield was obtained from the stem bark of P. thonningii (22.67%). Phytochemical analysis revealed the presence of tannins, saponins, alkaloids, phenolic compounds, triterpenes, and reducing sugars. The leaves of P. thonningii exhibited the highest total flavonoid content (313.82 µg Eq R/mg DE), whereas the leaves of P. suberosa showed the strongest antioxidant activity, reaching 90.70 mg Eq AA/g DE and 430.50 µmol Eq FeSO₄/mg DE in the phosphomolybdate and FRAP assays, respectively. The largest inhibition zone (20 mm) was produced by the stem bark extract of P. thonningii against Candida albicans. In addition, the stem bark extract of P. suberosa and both leaf and stem bark extracts of P. thonningii exhibited a minimum inhibitory concentration (MIC) of 1.562 mg/mL against S. aureus n0689. These findings provide preliminary in vitro evidence supporting the traditional use of both species. Although their antioxidant and antimicrobial activities were low, further studies are needed to isolate the active constituents, elucidate their mechanisms of action, and evaluate their safety before therapeutic application.