ABSTRACT
OBJECTIVE To investigate the combined effect of cefoperazone/sulbactam with levofloxacin(group 1) and polymyxin B with rifampin(group 2) on 43 isolates of multi-drug-resistant Pseudomonas aeruginosa. METHODS The minimal inhibitory concentration(MIC) of all the antibiotics mentioned above was determined by agar dilution method.Fractional inhibitory concentration(FIC) index was calculated for all the selected isolates with all combinations,and the activities of antibiotics alone and in combination against the selected strains were evaluated. RESULTS The MIC of all the combined antimicrobials was reduced significantly(P
ABSTRACT
A preparation of water soluble components(EA) was made from carpophores of Elfvingia applanata(Pers.) Karst and its in vitro antibacterial activity on a number of bacterial species was examined by macrobroth dilution assay. Among 16 species of bacteria tested, the most potent antibacterial activity was observed against Staphylococcus epiderrnidis and Proteus vulgaris, of which MICs were 1.25 mg/ml. To investigate the antibacterial effects in combinations of EA with quinolone antibiotics, such as ciprofloxacin, enoxacin, lomefloxacin, norfloxacin, and ofloxacin, the fractional inhibitory concentrations(FICs) and the fractional inhibitory concentration indices(FICIs) for four bacterial strains were determined by macrobroth dilution checkerboard assay. Combinations of EA and quinolones exhibited either additive or indifferent effects of antibacterial activity in most instances. However, both synergistic and antagonistic effects were not observed in any cases.