Abstract

The antibacterial activity of chloramphenicol was tested using some potential human pathogens, which are Streptococcus pyogen, Staphylococcus aureus and Salmonella typhi. The concentration of chloramphenicol used were 100mg/ml, 200mg/ml, 300mg/ml 500mg/ml. using agar well diffusion techniques, S. pyogen has the highest susceptibility to chloramphenicol with a mean zone of inhibition 29.58mm while the least mean zone of inhibition was recorded for S. aureus with 15.45mm. In the comparison of S. pyogen to S. aureus, S. pyogen to S. typhi and S. typhi to S. aureus at 100mg/ml to 500mg/ml was 55.67%, 51.57% and 7.64% at 100mg, at 200mg it was 51.42%, 40.44%, and 18.44% at 300mg it was 49.69%, 31.52%, 26.51%, at 500mg it was 18.94%, 1.21% and 36.354% respectively. S. pyogen showed to be more susceptible compare with the remaining two.

Key words: Chloramphenicol, Staphylococcus aureus, Streptococcus pyogen, Salmonella typhi