Preliminary phytochemical screening and in vitro antimicrobial investigation of the stem bark petroleum ether extract of Croton zambesicus Muell Arg.
The petroleum ether extract of Croton zambesicus Muell Arg. was subjected to preliminary Phytochemical screening and in vitro antimicrobial tests. The Phytochemical tests were conducted using standard methods of analysis and the extract revealed the presence of cardiac glycosides and steroids. Antimicrobial effects of the plant extract were assayed using the plate-hole agar disc diffusion and nutrient dilution techniques. Test micro-organisms were Shigella dysenteriae, Staphylococcus aureus, Streptococcus pyogenes, Escherichia coli, Pseudomonas aeruginosa, Proteus vulgaris and Candida albicans, were all clinical isolates. The extract inhibited all the tested organisms at various concentrations except Proteus vulgaris and C. albicans. It showeda minimum inhibitory concentration (MIC) of 25 mg/ml against S. dysenteriae, S. aureus and E. coli while MIC against S. pyogenes and p.aeruginosa were 100 and 50 mg/ml respectively. The minimum bacterial concentration (MBC) was 50 mg/ml against S. dysenteriae, S. aureus and E. coli while MBC against S. pyogenes and P. aeruginosa was 100 mg/ml. Therefore it was concluded that this study laid credibility for the use of the plant against stomach and urinary tract infections whose causative agents are most of the organisms used in this study.