COMPARATIVE STUDY ON THE EFFECIENCY OF BLEACH, PHENOLICS AND ETHANOL ON STAPHYLOCOCCUS AUREUS AND PSEUDOMONAS AERUGINOSA

Disinfectants are chemicals which have the ability to destroy or inhibit the growth of microorganisms and which are used for this purpose. They are used to control the growth of microbes on both living tissue and inanimate objects and plays a vital role in global infection control as a crucial armament against transmission of infections. They are also widely used in various ways; especially in microbial laboratory. Disinfectants have varying mode of action against microbial cells due to their chemical diversity i.e. the mode of action of disinfectants differ greatly according to the chemical substance present. No single disinfectant is appropriate for all circumstances and the choice of the disinfectant to be used depends on a particular situation. The most commonly used disinfectants in laboratories are ethanol, bleach and hand soap. In this study, a comparing experiment on three disinfectants’ efficiency (Ethanol, hypo and Dettol) were conducted against Staphylococcus aureus and Pseudomonas aeruginosa .The antimicrobial effectiveness of these disinfectants was determined using agar diffusion (paper disc) method. The undiluted concentrations of the disinfectants showed varying zones of inhibition against the test organisms, on Staphylococcus aureus it ranged from 12.5mm (dettol), to 8mm (hypo) and finally 0mm (ethanol), on Pseudomonas aeruginosa, 3mm (dettol) to 10mm (hypo) and finally 0mm (ethanol). The different dilutions also showed varying zone of inhibition against the test organism. The result showed that 100% hypo is efficient on the test organisms, and 95% phenolic had a better effect on Staphylococcus aureus than Pseudomonas aeruginosa, while ethanol showed least sensitivity. 70% concentration gave the highest effect on Staphylococcus aureus as compared with Pseudomonas aeruginosa.