Study on the antibacterial activity of liquid hand-wash containing triclosan against clinical samples

Abstract

In recent times the use of antibacterial hand washes has been heavily promoted to a healthconscious public. The purpose of this study was to investigate in vitro antimicrobial activity of liquid hand soap containing triclosan against microorganisms. Eight clinical isolates were used in this studyand they were Pseudomonas aeruginosa, Klebsiella pneumoniae, Escherichia coli, Salmonella typhi, Proteus vulgaris, Shigella flexneri, Bacillus subtilis and Staphylococcus aureus. Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) was determined for the microorganisms through Broth Microdilution method. Kirby-Bauer disc diffusion test of the same organisms was done using the following antibiotics: Erythromycin (15g), Chloramphenicol (30 g), Ciprofloxacin (5g), Gentamicin (10 g), Kanamycin (10 g), Nalidixic acid (30 g), Penicillin (10g), Streptomycin (10g), Tetracycline (30 g). In this study, Salmonella typhi showed the highest MIC value (3.0 ml of stock solution) and Bacillus subtilis, Staphylococcus aureus had shown the lowest MIC value (0.6 ml of stock solution). Besides, Klebsiella pneumoniae, Pseudomonas aeruginosa, Escherichia coli, Proteus vulgaris, Shigella flexneri had shown the values 2.6 ml, 2.4 ml, 2.0 ml, 1.0 ml, 0.8 ml of stock solution respectively. All of the clinical isolates taken for the study had shown resistant characteristics against at least six tested antibiotics and three isolates were resistant to all the nine antibiotics. It is possible that antibacterial liquid hand-washes have the antibacterial agents (e.g. Triclosan) that can either kill or inhibit the bacterial cells. It might be possible that some bacterial strain can develop resistant properties which leads to their survival even at higher concentration of soaps and antibiotics.