The effect of temperature, salinity and antimicrobial agent on growth and viability of Aeromonas hydrophila

Abstract

Aeromonas hydrophila bacteria have been pathogen of Motile Aeromonads Septicemia disease that infects all of the freshwater fish. Control of microbe growth can be done by manipulating environmental factors and utilizing antimicrobial agents. The purpose of this study was to investigate the effect of temperature, salinity, and antimicrobial on the growth and viability of A. hydrophila. The treatments of the study consisted of temperature, salinity, and antimicrobial tests. Temperature treatment used Trypticase Soy Broth (TSB) medium incubated at 4˚C, 28˚C, 37˚C, and 70˚C. Trypticase Soy Agar (TSA) added with NaCl of 0%, 3%, and 10% in salinity treatment. Antimicrobial treatment was performed by disc diffusion method using chloramphenicol (25 ppm and 50 ppm), Phyllanthus niruri extract (3 ppt and 30 ppt), formaldehyde (0.4% and 4%), penicillin (25 ppm and 50 ppm), and NaCl 0.9% (control). All treatments were incubated for 24 hours at 28˚C and were observed for bacterial growth. The study showed that A. hydrophila bacteria were growth optimally in medium with salinity 0% and 3% after incubated in temperatures of 4˚C, 28˚C, and 37˚C. Antimicrobial that inhibits the growth of A. hydrophila was Chloramphenicol 25 and 50 ppm; Phyllanthus niruri extract 30 ppt and formaldehyde 0.4% and 4%.