Isolation of bacteriophage with lytic activity against aeromonas hydrophila

An abstract of the research paper was presented to the Faculty of Veterinary Medicine, Universiti Malaysia Kelantan, in partial requirement for the course DVT 55204 – Research Project. Aeromoniasis caused by Aeromonas hydrophila is a disease associated with hemorrhagic septicemia and epizootic ulcerative syndrome that causes mass mortalities in fish and subsequent economic loss in the aquaculture industries. Its zoonotic capability to cause systemic illness in humans and known antimicrobial resistance prompted an alternative other than the usage of antibiotics such as bacteriophage. Hence, this study is conducted to isolate potential bacteriophages that target A. hydrophila through the isolation of bacteriophages with lytic activity against A. hydrophila. Three water and one soil samples were collected from various sites in Kota Bharu, Kelantan. Isolation of the bacteriophage was carried out by performing Spot-test, enrichment isolation, picking plaques, serial dilution, plaque assay, and purification. The plaque formation was measured, and host-range analysis was performed. In this study, bacteriophage with lytic activity against A. hydrophila was isolated from the SPC water sample obtained from the wastewater drainage to Sungai Pengkalan Chepa. The study showed that the plaques formed have very small plaque sizes, measuring less than 1 mm with regular, pin-point shapes. The bacteriophage shows narrow spectrum activity by only targeting a specific strain of A. hydrophila, which is the K3T8 isolated from the Red Hybrid Tilapia, Oreochromis spp. Interestingly, we also managed to isolate lysogenic bacteriophage from the UMK and SPC sample against A. hydrophila which is the K3T10 strain. This study provides valuable insights for further research into narrow-spectrum bacteriophage with lytic activity against A. hydrophila as future bacteriophage therapy.
Keywords: Aeromonas hydrophila, bacteriophage, aquaculture