The effect of ultrasound on Salmonella javiana, Aeromonas hydrophila, Yersinia ruckeri, Edwardsiella ictaluri, and Escherichia coli decontamination

Water pollution is a growing problem in today’s societies and will keep growing if certain measures are not taken. Dangerous bacteria that contaminate wounds, fish, and water can lead to less food and water for communities. Everyday there are new ideas to clean water without using chemicals like chlorine that can harm the human body. Ultrasonic waves, which are sound waves above 20,000 hertz, may be a way to decontaminate water of bacteria. To test whether or not ultrasound is an effective way to kill bacterial colonies, 5 different bacteria (Salmonella javiana, Aeromonas hydrophila, Yersinia ruckeri, Edwardsiella ictaluri, and Escherichia coli) underwent ultrasound exposure at 4.6 mhz and 9.6 mhz for 5 minutes each. Each bacteria was split into 3 groups, one being control, one being 4.6 mhz, and the last being 9.6mhz. This was completed by inoculating water with certain bacteria, then exposing it to ultrasound, and lastly performing serial dilutions in order to count individual bacterial colonies. Following the dilutions, each 1 mL test tube had 20 microliters removed from it and placed onto a quadrant of a petri dish three times, ending up with 2 petri dishes with 24 20 microliter dots. The quadrants of the petri dishes were labeled by their dilution ratio. After incubation, bacterial colonies in the dilution ratio that have the least amount of colonies (but more than 5) were counted and were reverted back to the original inoculation to find total amount of colonies after ultrasound exposure