CONTROLLING PSEUDOMONAS AERUGINOSA IN CONTAMINATED WATER AND MILK VIA SPECIFIC BACTERIOPHAGES

In this study Pseudomonas aeruginosa was isolated from a sewage water sample collected from treatment plant of El-kawther City, Sohag, Egypt. Sensitivity test of Pseudomonas aeruginosa to 19 antibiotics indicated that two (ciprofloxacin and meropenem) out of 19 antibiotics tested exhibited inhibitory effect against P. aeruginosa. Ciprofloxacin was the most efficient antibiotic followed by meropenem, they exhibited inebriation zones of 30 and 25 mm. in diameters, respectively. P. aeruginosa was found to be tolerant to salinity stress. It has the ability to grow in 9% NaCl. In addition, P. aeruginosa was tolerant to pH levels ranging from 4 -10. 
Bacteriophages specific to P. aeruginosa were successfully isolated from the same sewage water sample. Bacteriophages were applied to water and milk contaminated with P. aeruginosa at 4 and 37ºC. Due to application of phages number of bacteria was gradually decreased in both water and milk and no bacterial cells were detected after 24 hr. at 4 and 37ºC. Whereas, number of phage particles increased and the highest number was recorded after 24hr. 
Therefore, application of specific phages to foodstuffs is highly recommended to avoid contamination or to get rid of this pathogenic bacterium