Abstract

Concoctions of Azadirachta indica Linn (Neem) and Garcinia kola Heckel (Bitter kola) are commonly used for medicinal purposes in most Nigerian rural communities, because they are believed to possess some healing properties. The antibacterial activity of both neem and bitter kola was evaluated by agar well diffusion method against Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, Staphylococcus aureus and Streptococcus pneumoniae. Both neem and bitter kola leaf extracts in varying concentrations showed moderate antibacterial activity against the clinical pathogens. Cold water and hot water extracts showed better activity as compared to the methanol and ethanol extracts. Gram positive bacteria (S. aureus and S. pneumoniae) were more susceptible to the plant extracts than the Gram negative pathogens (K. pneumoniae and P. aeruginosa). The MICs of the plant extracts were determined at varying effectiveness of 25 and 12.5 mg/ml. The results obtained in this study give credence to the traditional use of neem and bitter kola in the treatment of infectious diseases in Nigerian rural communities.

Key words: Azadirachta indica Linn., Garcinia kola Heckel, clinical pathogens, resistance, Nigeria.