Phytochemical Screening and Antibacterial Efficacy of Albizia anthelmintica and Vepris glomerata Leaves

Introduction Medicinal plants are important sources of bioactive compounds used in traditional and modern medicine. Albizia anthelmintica Brongn. and Vepris glomerata (F. Hoffm.) Engl. are commonly used in Ethiopian traditional medicine to treat bacterial infections, fever, and inflammation, but scientific evidence of their antibacterial activity is limited. Objective This study aims to evaluate the phytochemical composition and in vitro antibacterial activity of leaf extracts of A. anthelmintica and V. glomerata using solvents of varying polarity. Methods Leaf powders of each plant were successively extracted with petroleum ether, chloroform, acetone, and methanol. The extracts were screened for major phytochemicals such as alkaloids, flavonoids, phenolics, saponins, tannins, terpenoids, steroids, and glycosides using standard qualitative methods. Antibacterial activity was determined by the agar well diffusion method against Staphylococcus aureus (ATCC 25923), Escherichia coli (ATCC 25922), Klebsiella pneumoniae (ATCC 700603), and Pasteurella multocida (clinical isolate, EPHI) at concentrations of 25, 50, and 100 mg/mL. Ciprofloxacin was used as the positive control, and 1% DMSO served as the negative control. Results Phytochemical screening revealed a range of secondary metabolites in both species, with variations depending on solvent polarity. The chloroform and acetone extracts of A. anthelmintica exhibited the strongest antibacterial activity against Klebsiella pneumoniae (29.5 ± 0.36 mm) and P. multocida (25.4 ± 0.62 mm). Likewise, the petroleum ether and chloroform extracts of V. glomerata showed notable inhibition against K. pneumoniae (29.7 ± 0.46 mm) and P. multocida (23.1 ± 0.53 mm). All extracts demonstrated concentration-dependent antibacterial effects, with statistical analysis (ANOVA, p < 0.05) confirming significant differences among them. Conclusion A. anthelmintica and V. glomerata leaves exhibit potent antibacterial activity against Gram-positive and Gram-negative bacteria, likely due to multiple bioactive phytochemicals. These findings support the traditional use of these plants and suggest potential for the development of plant-based antimicrobials.