الملخص

In this study, the sensitivity and resistance of six types of bacterial isolates, Escherichia coli, pseudomonas aeruginosa, Staphylococcus aureus, Proteus vulgaris, Proteus mirabilis, and Klebsiella pneumoniae, against 10 antibiotics were tested for 10 antibiotics, Ciprofloxicine (CF) 25 g / ml Amoxicillin (AX) 50 g / ml, Ampicillin (Am) 50 µg / ml, Erythromycin (Ery) 15 µg / ml, Gentamycin ( GN) 25 g / ml, Rifampicin (RA) 50 µg / ml, Streptomycin (Sm) 25 µg / ml, Tetracyline (TE) 15 µg / ml Trimethprim (Tri) 10 µg / ml Nalidixic acid (Nal) 30 µg / ml. The bacterial isolates showed different resistance to most antibiotics. One isolate of each bacterium was selected for subsequent experiments. The aqueous and ethanol extracts of Citrus aurantium L fruit were prepared. The inhibitory effect of the prepared plant extracts on the selected bacteria was investigated by using the Agar diffiuision method and the Turbidity method. The prepared plant extracts showed a clear growth inhibitory activity, which was estimated by measuring the inhibition zone with a millimeter of studied bacteria. The results obtained showed that the value of the growth inhibitory activity increased with increasing the concentration of the extracts. Sub minimum inhibition concentration of plant extracts was used as a curing to remove antibiotic resistance of the bacterial species under study. Varying values ​​for the percentage loss of antibiotic resistance were obtained as a result of the efficacy of the extracts, but some extracts did not show curing efficacy. The results of the curing experiments were supported by the characterization of the plasmid DNA on the agarose gel of the curing isolates. Electrophoresis showed the disappearance of the plasmid DNA bundles from the agarose gel for most of the bacteria under study compared to the non-curing isolates.