Evaluation of antimicrobial activity of various bark extracts of bombax malabaricum

Abstract

This study was carried out with an objective to investigate the antibacterial and antifungal potential of Bark of Bombax malabaricum. Antibacterial activity of successive extracts (petroleum ether, chloroform, acetone, alcohol, water) of bark were carried out against two Gram positive bacteria – Bacillus Subtilis and Staphylococcus aureus and two Gram negative bacteria – Escherichia coli, Pseudomonas aeruginosa. The antifungal activity of the extracts was evaluated on two common pathogenic fungi – Aspergillus niger and Candida albicans. The testing was done by the agar diffusion method. Zones of inhibition of extracts were compared with that of standard Amoxycillin for antibacterial activity and Ketoconazole for antifungal activity. The extracts showed antibacterial and anti-fungal activities comparable with that of standard against the organisms tested. The results showed that the Petroleum ether and chloroform extracts showed no activity while the alcoholic extract showed more activity than the acetone and aqueous extracts. The highest inhibitory activity was determined for alcoholic extract against E.coli (19.50 ± 0.5000 mm, inhibition zone diameter). On the other hand, the weakest inhibitory activity was determined against P. aeruginosa for aqueous extract (7.00 ± 0.5774 mm, inhibition zone diameter).