The phytochemical analysis and antibacterial effects of stem bark extracts of Brachystegia eurycoma harms
Plant based antimicrobials represent a vast potential of untapped sources of medicines. Antimicrobial sensitivity patterns change over time due to resistance developed by microorganisms, underpinning the great need for search of novel antimicrobial drugs. Phytochemical and antibacterial effects of crude aqueous (hot and cold) and alcohol extracts of stem bark of Brachystegia eurycoma was investigated using standard methods. The preliminary phytochemical screening revealed the presence of saponins, alkaloids, steroids and tannins as major components. Also, of the three different extracts tested against four pathogenic bacteria (Sphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa and Proteus vulgaris), only the cold aqueous extract showed a mild zone of inhibition (3mm) against Escherichia coli, with an MIC of 12.5mg/ml and MBC of 25mg/ml. This suggests that cold aqueous extract of B. eurycoma has antibacterial activity, which might account for its inclusion in traditional herbal preparations in the treatment of wounds and infections.
Key words: Brachystegia eurycoma, phytochemical, stem bark, antibacterial, extracts