Susceptibility Profiles of Enterococcus faecalis to Selected Antibiotics
This study was conducted in order to determine the susceptibility of Enterococcus faecalis to the antibiotics penicillin, erythromycin, tetracycline, chloramphenicol and gentamicin through measuring the zone of inhibition. The susceptible, intermediate and resistant categories were assigned on the basis of the critical points recommended by the Clinical and Laboratory Standards Institute. E. faecalis was susceptible to tetracycline as low as 20 μg/20 μl. Starting at a dose of 60 μg/20 μl and 200 μg/20 μl, the bacterium was susceptible to penicillin and erythromycin, respectively. The bacterium was resistant to chloramphenicol even at the highest dosage of 400 μg/20 μl. Meanwhile, from 5 to 100 μg/20 μl, the bacterium was resistant to gentamicin and the classification was changed into intermediate starting at 200 μg/20 μl.
Keywords: Enterococcus faecalis, antibiotics, susceptibility
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