Antimicrobial activity of the ethanol extract and fractions of the seeds of Garcinia kola Heckel (Guttiferae)

The crude ethanol extract, aqueous and chloroform fractions of the seeds of Garcinia kola Heckel (Guttiferae) was investigated for antimicrobial activity. Agar well diffusion and minimum inhibitory concentration determinations were the methods employed for the study. Clinical bacterial and fungal isolates were used as indicator organisms while standard antimicrobial agents were included in the study. The crude ethanol extract showed significant inhibitory activity against clinical isolates of both Gram positive and Gram negative organisms. It was active against Staphylococcus aureus, Bacillus subtilis, Streptococcus viridans, Escherichia coli, Pseudomonas aeroginosa and Klebsiella pneumonia. It also showed significant inhibitory activity against fungi like Penicillium notatum, Aspergillus niger and Candida albicans. Both the aqueous and chloroform fractions showed activity against the clinical isolates of S. aureus, E. coli and P. aeruginosa. The MIC values obtained ranged between 2.5 and 7.5 mg/ml for bacteria and fungi isolates. The results showed that the crude ethanol extract has broad spectrum of activity, while the fractions exhibited narrow spectrum of activity, since they were active against S. aureus, E. coli, and P. aeruginosa only. These observations could be the basis for the usefulness of the seeds of G. kola in the treatment remedies for microbial infections.