Abstract

The antibacterial properties of ethanolic, dichloromethane (DCM) and acetone ofZanthoxylum chalybeum stem bark were evaluated with the gram negative bacteria (Escherichia coli, Salmonella typhi, Pseudomonas aeruginosa) and gram-positive bacteria (Staphylococcus aureus) and Candida albicans. All tested bacteria have been shown to be resistant to the acetone extracts whereas, only S. aureus growth has been inhibited by DCM extract (14 mm). Moreover, the ethanolic extract inhibited growth of S. typhi, (17 mm)P. aeruginosa (23 mm) S. aureus (16 mm) around agar well. However, E. coli and C. albicans have not been inhibited by ethanolic extract. For minimum inhibitory concentrations (MICs) determination, acetone extract has no activity against all microorganisms tested whereas both ethanol and DCM exhibited strong activity to the S. aureus at 32 µg/ml of MIC value. The ethanol extract has exhibited low activity against S. typhi, and P. aeruginosawith respectively 250 and 500 µg/ml of MIC values.

Key words: Zathoxylum chalybeum, antimicrobial activity, crude extracts.