The roots of Chasmanthera dependens were studied to determine their active constituents and antimicrobial activity. A phytochemical investigation of C. dependens using chloroform and methanol extracts led to the isolation and identification of the following secondary metabolites; alkaloids, flavonoids, tannins, phenolics, carbohydrates, reducing sugars, terpenoids, steroids, saponins. The antimicrobial activities of these extracts were possibly linked to the presence of secondary metabolites mentioned above. Agar well diffusion techniques and macrobroth dilution methods were used to screen the methanol and chloroform root extract of the medicinal plant (C.dependens) for antimicrobial activity against the following bacteria pathogens: Escherichia coli, Enterococcus specie, Bacillus specie, Klebsiella pneumonia, Pseudomonas aeruginosa, Staphylococcus aureus. The chloroform extract showed inhibition against the following pure culture, Staphylococcus aureus(12.5 ± 2.12), Escherichia coli (12.0 ± 2.83) and Pseudomonas aeruginosa(12.0 ± 1.41) while the methanol extract showed inhibition against Staphylococcus aureus(6.75 ± 0.36), Escherichia coli (8.5 ± 0.71) and Pseudomonas aeruginosa(No Zone of Inhibition)in the concentration of 50 mg/ml. The Minimum Inhibitory concentration (MIC) of C.dependens(methanol extract)ranged from 6.3mg/ml to 100mg/ml while MIC of the antibiotics (ciprofloxacin) ranged from 7.8µg/ml to 250µg/ml.Theresults of this study indicated that the roots of C.dependens have great activity on some bacteria, thus confirming some of the therapeutic effects of the plant.

Keywords: Phytochemicals, antimicrobial activity, chasmenthera dependens, dilution, bacteria and zone of Inhibition