Activity of synergistic combination Amoxy-cassia against Salmonella
Ali, N.Hassan.; Kazmi, S.Urooj.; Faizi, S.
Pakistan Journal of Pharmaceutical Sciences 20(2): 140-145
2007
ISSN/ISBN: 1011-601X PMID: 17416570 Document Number: 606455
A study was conducted to formulate a new, cost effective antimicrobial combination for Multi-Drug Resistant (MDR) Salmonella enterica serovar typhi (SEST) based on the synergistic activity of amoxicillin with the aqueous fruit solution of Cassia fistula (CFF), a medicinal plant found in Pakistan which, when tested alone, has weak antimicrobial activity against blood isolates of MDR SEST. The MIC of MDR SEST for amoxicillin and CFF alone was 750 micro g/ml and 3750 micro g/ml, respectively. The MIC of amoxicillin in combination with CFF was 23.4-187.5 micro g/ml and 0.37-1.56 micro g/ml for MDR and MDS SEST, respectively. Fractional Inhibitory Concentration Index (FICI) using checkerboard titration suggested synergism for 80% MDR and MDS SEST tested, and no antagonism was observed. Time-kill kinetics showed difference >log2 in the CFU of CFF having sublethal amoxicillin concentrations. This novel combination is named as Amoxy-cassia. In vivo, it is found to be nontoxic at 1 g/body weight of mice.