Potentials of leaf extracts of Anogeissus leiocarpa (DC.) Guill. & Perr. Against two pathogenic microbes

Plants have long served as dependable sources of therapeutic agents, and their contribution to drug discovery continues to attract widespread global attention. Anogeissus leiocarpa (DC.) Guill. & Perr. possesses considerable ethnobotanical relevance for the management of various ailments. This study evaluated the phytochemical composition and antibacterial activity of the ethanolic leaf extract of A. leiocarpa against Salmonella typhimurium and Escherichia coli. Phytochemical screening and antibacterial assays were conducted using validated analytical procedures. The results revealed the presence of tannins, phenols, glycosides, steroids, alkaloids, flavonoids, saponins, terpenoids, carbohydrates, and resins in varying concentrations. Quantitative analysis showed alkaloids (39.00 mg/g) as the most abundant phytochemical, while phenols (12.90 mg/g) were the least abundant. The ethanolic leaf extract of A. leiocarpa (EtLEAL) exhibited significant (p < 0.05) zones of inhibition against the test organisms in a concentration-dependent manner. The minimum inhibitory concentrations (MICs) of EtLEAL were ≤ 6.25 mg/mL for S. typhimurium and 12.5 mg/mL for E. coli, while the minimum bactericidal concentrations (MBCs) were 100 mg/mL and > 100 mg/mL, respectively. The calculated MBC/MIC ratios of 16.0 and 8.0 indicated a comparatively weaker bacteriostatic effect of the extract against S. typhimurium than E. coli. These findings suggested the need for further studies employing higher extract concentrations, different plant parts, and alternative extraction solvents to enhance antibacterial activity.