الملخص

ABSTRACT Out of 50 samples obtained from humans of different environments, 18 were diagnosed as Staphylococcus aureus. 6 out of these diagnosed isolates were tested for elimination of resistance to antibiotics by chloroform and acetone extracts of the plant Olivera dicumbens. Bacterial isolates were treated with subminimum inhibitory concentrations (sub-MIC) of the above mentioned extracts. Percentage of loss of resistance of colonies to antibiotics was measured. Chloroform extract at the concentration 250 mg/ml was found to be the most effective concentration inducing resistance of this bacteria to the antibiotic Ciprofloxacin. Highest percentage loss of resistance (38%) was found in the 5th isolate. For loss of resistance to the antibiotic Ampicillin, highest resistance (36%) was found in the 6th isolate. On the other hand, the least loss of resistance was found against the antibiotic Nalidixic acid in the 5th isolate. No clear effect was obtained with the acetone extract. It can, therefore, be concluded that the chloroform extract may have acted as mutagenic, eliminating the resistance of certain Staphylococcus aureus isolates to some antibiotics.