OBJECTIVETo investigate the prevalence of kanamycin (kan) and ampicillin (amp) resistant bacteria in public drinking water.

METHODSBacteria containing kan and amp resistant genes were amplified by PCR and further characterized by colony hybridization and transformation studies. The genus of kan and amp resistant bacteria was determined with standard methods.

RESULTSAmong the 625 drinking water samples, 400 contained kan and amp resistant bacteria and the percentage was 42.5% and 57.5%, respectively, which was further confirmed by the amplification of a 810 bp kan resistant gene and a 850 bp amp resistant gene. Of the 170 kan resistant bacteria, 90 were Gram negative and 80 were Gram positive. Of the 230 amp resistant bacteria, 160 were Gram negative while 70 were Gram positive. Salmonella, Shigella, Staphylococcus, Streptococcus, and E.coli were detected as 13%, 11%, 17%, 30%, and 29%, respectively. Bacterial strain DH5alpha transformed with plasmids isolated from kan and amp resistant bacteria confirmed that the antibiotic resistant genes were mediated by plasmids.

CONCLUSIONDrinking water is contaminated with kan and amp resistant bacteria due to poor sanitary conditions.

Anti-Bacterial Agents ; pharmacology ; Bacteria ; drug effects ; isolation & purification ; Drug Resistance, Bacterial ; Pakistan ; Polymerase Chain Reaction ; Water Microbiology ; standards ; Water Supply ; standards

Silver nanoparticles are considered as good antimicrobial agent. AgNPs were synthesized by mixing silver nitrate solution with citrus sinesis extract for 2 h at 37 °C and analyzed by UV-visible spectra, SEM, XRD, and FTIR. AgNPs were tested against B. subtilis, Shigella, S. aureus, and E. coli. Minimum inhibitory concentration of AgNPs was 20 µg/mL for B. subtilis and Shigella and 30 µg/mL for S. aureus and E. coli. Antibiofilm activity (80% to 90%) was observed at 25 µg/mL. AgNPs were stable for five months with sustained antimicrobial activity. Biosynthesized AgNPs can be used to inhibit food poisoning microbial growth.
Anti-Bacterial Agents ; pharmacology ; Bacillus subtilis ; drug effects ; Bacteria ; drug effects ; Citrus sinensis ; chemistry ; Escherichia coli ; drug effects ; Foodborne Diseases ; prevention & control ; Metal Nanoparticles ; analysis ; Plant Extracts ; pharmacology ; Shigella ; drug effects ; Silver ; pharmacology ; Staphylococcus aureus ; drug effects