Background: Salmonella infection remains endemic in northern Nigeria, with rising antimicrobial resistance. While Acacia nilotica has been widely studied, research has focused mainly on bark and roots.
Aims: this study provides novel clinical evidence on the antibacterial activity of its leaf extracts against Salmonella isolates from patients in Kano.
Methods: Four hundred stool samples from patients screened for typhoid were enriched in Selenite F broth and cultured on selective media. Presumptive Salmonella isolates were identified phenotypically by morphology, Gram staining, and biochemical profiling. Leaves of A. nilotica were extracted with water and ethanol. Phytochemical screening was performed, and antibacterial activity was assessed by agar diffusion at graded concentrations. MIC and MBC were determined by broth dilution.
Result; Fourteen isolates (3.5%) were identified as Salmonella phenotpically. Phytochemical analysis revealed abundant tannins, alkaloids, saponins, steroids, and glycosides. Both extracts exhibited concentration-dependent inhibition against a subset of isolates, with ethanol showing higher activity (zones up to 20 mm at 50 mg/mL) than water. MICs ranged from 25–50 mg/mL, and MBCs were typically 50 mg/mL for susceptible isolates. Activity was substantially lower than ciprofloxacin.
Conclusion: A. nilotica leaves possess measurable but modest anti-Salmonella activity. While weaker than reports for bark and roots, the leaf-based approach offers sustainability and safety advantages. Further molecular identification is warranted, with tannins, alkaloids, and saponins prioritized for bioassay-guided isolation.

Background of study: Antimicrobial resistance (AMR) has emerged as a critical global health threat, diminishing the efficacy of existing antibiotics and complicating the management of infectious diseases. Medicinal plants remain an invaluable source of new antimicrobial agents. The Fabaceae family is abundantly represented across Northern Nigeria and forms a cornerstone of ethnomedicine for treating bacterial and fungal infections. However, scientific evidence on their antimicrobial activities remains fragmented.
Aim and scope of paper: This systematic review synthesizes evidence (2018–2025) on the antimicrobial activities of selected Fabaceae species found in Northern Nigeria.
Methods: Using PRISMA 2020 guidelines, electronic searches were conducted in PubMed, Scopus, Web of Science, Google Scholar, ScienceDirect, AJOL, and SpringerLink. Peer-reviewed experimental studies evaluating antimicrobial activities of Fabaceae plants native to or present in Northern Nigeria were included. Data were narratively synthesized due to methodological heterogeneity.
Results: Thirty eligible studies were identified, covering Parkia biglobosa, Tamarindus indica, Acacia senegal, Acacia nilotica, Prosopis juliflora, Senna alata, Erythrina senegalensis, Tephrosia vogelii, Cassia fistula, Pterocarpus erinaceus, Pterocarpus tinctorius, and Bauhinia species. Extracts especially methanolic and ethanolic showed significant antibacterial and antifungal activities, with inhibition zones ranging from 12–30 mm and minimum inhibitory concentrations (MICs) between 0.25–4 mg/mL. Some species exhibit exhibits and virulence-attenuating effects.
Conclusion: Fabaceae plants in Northern Nigeria demonstrate substantial antimicrobial potential and warrant deeper investigation for drug development. Future research should focus on bioactive compound isolation, mechanistic elucidation, toxicity assessment, and in vivo validation.