DOI: 10.36347/sjams.2015.v03i05.037

Pages: 1978-1984

The importance of potable water as a natural resource is vital for human health. Enterococcus faecalis, Salmonella typhimurium, Pseudomonas aeruginosa and Streptococcus faecalis are commonly linked to waterborne disease epidemics and so were chosen for this research. The aim of this study was to evaluate the impact of low frequency ultrasound on pathogens in polluted water hence 200 ml of bacterial suspensions were prepared at an optical density of 0.17 at  440nm and were subjected to sonication using a 20 kHz probe (13.88W/cm2). Samples were taken at 0, 2, 5, 15 and 30 minutes, serially diluted and enumerated using the viable plate count technique. Results revealed that Enterococcus faecalis (Gram positive bacteria which has a tough peptidoglycan cell wall) demonstrated a “declumping” effect following 2 minutes sonication and also Pseudomonas aeruginosa, Salmonella typhimurium(Gram negative bacteria) and Streptococcus faecalis(Gram positive) demonstrated a large reduction in bacterial cell numbers with increasing sonication time. Gram negative bacterial cell walls were more susceptible to damage induced by sonication, and this was evident in this study than the gram positive pathogens It is widely accepted that the use of ultrasound in combination with conventional biocides (chlorine) will results in a synergistic effect. This is the focus and intention of this study as declumping renders bacterial cells more susceptible to conventional chemical treatments.