THE SYNERGISTIC EFFECT OF AMPICILLIN AND GENTAMICIN ON STAPHYLOCOCCUS AUREUS AND ESCHERICHIA COLI

This project work investigated the synergistic effect of ampicillin and gentamicin on Staphylococcus aureus and Escherichia coli. Samples were collected from Ozoro in Isoko North Local Government Area of Delta State. The media used were prepared according to the manufacturers instructions into a conical flask plugged with cotton wool wrapped in aluminium foil and sterilized in an autoclave at 121OC for 15 minutes. The effect of ampicillin and gentamicin at different concentrations were tested on four (4) isolates of Staphylococcus aureus and Escherichia coli. Ampicillin was diluted to 25mg/ml and gentamicin was diluted to 8mg/ml. Escherichia coli had the highest organisms in O2 which is (8.6 x 103) and O1 (5.6 x 10)3, Staphylococcus aureus occurred lowest in both samples N1 (4.0 x 103) and N2 (3.0 x 103). Furthermore, the combined effects of ampicillin and gentamycin respectively. The highest zone of inhibition was 12mm while the lowest zone of inhibition was 2mm. Generally, the combined effect of gentamycin and ampicillin on resistant isolates was effective.