An inhibitory effect of aqueous garlic extract on 12 drug resistant clinical isolates Staphylococcus aureus and Pseudomonas aeruginosa growth was evaluated. The antimicrobial effect of aqueous garlic extract in different concentrations 60%, 50%, 40%, 30%, 20% and 10% was examined by well diffusion method and the antimicrobial sensitivity test for selected group of antimicrobial agents was examined by disc diffusion method. The results revealed that antibacterial activity of aqueous garlic extract at60%, 50% and 40% concentration characterized by clear inhibition effect on Staphylococcus aureus growth with range of diameter of inhibition zone was 14 mm. For Pseudomonas aeruginosa, high concentration of 60% gave an inhibition zone of 10 mm, while 50%, 40% and 30% concentrations gave a diameter of 9 mm. The results of antimicrobial sensitivity test revealed that 50% of isolates were sensitive to ciprofloxacin, whereas the resistance of the isolates for cefuroxime sodium, cefotaxime, amoxicillin/clavulanic acid and lincomycin were 100%, 92%, 83% and 67% respectively. The study concluded that the resistant and multiple antimicrobial agents resistant were common in the isolates, whereas all isolates tested were sensitive to aqueous garlic extract that could be used as an antibiotic for treatment of bacterial infections.
