Abstract
The antibacterial and antifungal activity of Garcinia kola of small and large seeds varieties were extracted in ethanol and water (cold and hot) and tested against some selected clinical bacterial and fungal isolates; Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, Bacillus subtilis and Pseudomonas aeruginosa at concentrations of 10, 20, and 30 mg/ml. The same concentrations were used against the fungi Candida albicans and Aspergillus niger. Agar well diffusion method was employed to determine the antimicrobial activity of the extracts against test microorganisms. The results showed that the small seed ethanol and aqueous (hot water) extracts exhibited more antimicrobial activity at a concentration of 30 mg/ml, with zones of inhibition ranging from 17 to 23mm for ethanol. The aqueous (hot water) extracts showed zones of inhibition ranging from 20 to 27mm. The extracts also showed antifungal activity against Aspergillus niger. The minimum inhibitory concentration (MIC) showed antimicrobial activity at lowest concentration of 0.008mg/ml and maximum concentration of 5.0mg/ml against Staphylococcus aureus. There were presence of phytochemical compounds such as flavonoids, tannins, saponins, steroids, cardiac glycosides, and reducing sugars. The results imply that the ethanol and aqueous extracts of Garcinia kola seed posses strong antibacterial and antifungal properties when compared with standard antibiotics amoxicillin; ciproxin; tetracycline and streptomycin used during the investigation, and hence its potential as a useful chemotherapeutic agent in the treatment of bacterial and fungal infections in humans.