Comparison of antibacterial and synergistic effects of some medicinal plants against the zoonotic bacterium (Aeromonas hydrophila)

Aeromonas hydrophila bacteria is an opportunistic bacterium that can reduce the use of chemical and synthetic drugs by using medicinal plants to inhibit its growth in food. Considering the antibacterial properties of three plants, Yarrow, Lavender and Thyme, this study was conducted with the aim of investigating the antibacterial and synergistic effects of these three plants against Aeromonas hydrophila bacteria. In this study, Aeromonas hydrophila bacteria was first prepared from fish samples and confirmed by biochemical and PCR methods. Then extraction was done by maceration method and the sensitivity of isolated bacteria was checked by disk diffusion method in Mueller Hinton culture medium. Also, the minimum inhibitory concentration of medicinal plants was investigated. According to the results, the prevalence of Aeromonas hydrophila bacteria was 5%. The isolated bacteria were resistant to all the investigated antibiotics. The lowest inhibitory concentration and the lowest lethal concentration were related to the yarrow plant, which shows its stronger antibacterial effects than the other two plants. The highest lethality concentration was reported for lavender plant, and this difference was statistically significant compared to other two plants (p<0.05). In general, tracking the prevalence of these pathogens in aquatic animals, along with investigating the prevalence of drug resistance and using alternative treatments such as the use of medicinal plants with antimicrobial properties that can overcome drug resistance and prevent the further spread of these factors in the aquaculture industry It seems necessary.