Evaluation of Antibacterial Activity of Some Medicinal Plants Used in Sudanese Folk Medicine for Treatment of Gastrointestinal Tract Infections

Abstract

Punica granatum, Citrullus colocynthes, Curcuma long, Albizia lebbeckandAzardirachta indicaare used in traditional medical practice in Sudan for the treatment of gastrointestinal tract infections. The methanol and aqueous extracts from different plant parts (Peel of fruits, rhizome, fruits, leaves, and Gum) respectively at a concentration of 100 mg/ml, were evaluated against 20 clinical isolates (2 were Salmonella typhi,5 Proteus mirabilis,4 Escherichia coli,5 Pseudomonas aeruginosa,3 Staphylococcus aureus, one was Salmonella para typhi B) and 5 standard bacterial strains (Staphylococcusaureus ATCC 25923), Bacillus subtilis (NCTC 8236), Escherichia coli (ATCC 25922), Salmonella typhi (ATCC1319106) and Klebsiella pneumoniae (ATCC 35657) were tested for their antibacterial properties using the Agar Diffusion Technique in vitro. Of all plants methanolic and aqueous extracts of Punica granatum were the most active with clinical isolates and standard bacterial strains showed relatively high antibacterial activity against most of the tested microorganisms with the diameter of inhibition zones ranging between 14 and 24 mm, whereas the methanolic extract of Curcuma long showed high antibacterial activity againstProteus mirabilis clinical isolate (1Z = 20 mm). Most susceptible Gram-negative clinical Isolates bacteria were Escherichia coli and Proteusmirabilis. Most susceptible Gram negative standard bacteria were Bacillus subtilis (NCTC 8236) and Escherichia coli (ATCC 25922) and least susceptible Gram negative bacterium was Klebsiella pneumoniae (ATCC 35657).In Gram positive standard bacteria, most susceptible was S.aureus (ATCC 25923).Antibiotics was used as standards drug for antibacterial assay. The results obtained appeared to confirm the antibacterial potential of the plants investigated, and their usefulness in the treatment of gastrointestinal tract infections.