Romie Angelo G. Azur, Angelou C. Prado (March 2013)
Philippine Science High School Western Visayas Campus – Department of Science and Technology (DOST-PSHS WVC), Brgy. Bito-on, Jaro, Iloilo City 5000, Philippines
ABSTRACT
One of the resistance mechanisms of bacteria to combat antibiotics is the production of β -lactamases, one kind of which is the Extended Spectrum Beta-lactamase (ESBL). First generations inhibitors have been developed but were counteracted instantly by the beta- lactamases. Novel inhibitors, those which are not structurally and chemically similar to beta- lactams are necessary. In 2002, Powers and other discovered that 3-[(4- chloroanilino) sulfonyl]thiopene-2- carboxylic acid is a competitive noncovalent inhibitor which inverted resistance to antibiotics in AmpC beta-lactamase-expressing bacteria. This study aimed to investigate the ability of 3-[(4- chloroanilino)sulfonyl]thiopene-2- carboxylic acid to potentiate the anti bacterial activity of Ampicillin-Sulbactam against an ESBL- mediated resistant strain of Klebsiella spp. The antibacterial activity of Ampicillin-Sulbactam, combined with and without 3-[(4- chloroanilino) sulfonyl]thiopene-2- carboxylic acid, against Klebsiella spp. was measured by determining the Minimum Inhibitory Concentration (MIC) (μ/mL) using the Broth Microdilution method. There were three replicates for 12 concentrations of each antibiotic dilution (from 0.125 μg/ml to 128 μg/ml . 3-[(4- chloroanilino)sulfonyl]thiopene-2- carboxylic acid combined with Ampicillin-Sulbactam had a lower MIC of 128 (μ/mL compared to the >128 (μ/mL MIC of Ampicillin-Sulbactam alone. Therefore, 3-[4- chloroanilino) sulfonyl]thiopene-2- carboxylic acid potentiated the antibacterial activity of Ampicillin-Sulbactam against an ESBL-mediated resistant strain of Klebsiella spp.
Keywords: 3-[(4- chloroanilino) sulfonyl]thiopene-2- carboxylic acid, ampicillin-sulbactam, antibacterial activity, broth microdilution method , Klebsiella spp. minimum inhibitory concentration.