Antibacterial activity of selective herbal extracts against fish pathogens, aeromonas hydrophila AND edwardsiella ictaluri

Abstract

The study was conducted to determine the antibacterial activity of two herbal plants against Aeromonas hydrophila and Edwardsiella ictaluri, causing disease in striped catfish (Pangasianodon hypophthalmus). The herbal plants,Phyllanthus urinaria and Psidium guajava, were extracted in methanol and water. The antibacterial activity was evaluated by disc diffusion method, minimum inhibitory concentration (MIC) and minimum bacterial concentration (MBC) were determined by broth dilution method. The study aimed to evaluate the effectiveness of solvent extraction using water compared to methanol. The assessment was based on the antibacterial activity of the extracts, measured through inhibition zones against two freshwater aquaculture pathogens, Aeromonas hydrophila and Edwardsiella ictaluri. The results indicate that herbal extracts prepared with water and methanol yielded the antibacterial activity outcomes for both guava leaves (Psidium guajava) and chamber bitter (Phyllanthus urinaria). Thus, our findings demonstrate that P. urinaria and P. guajava extracts by water also display the antimicrobial efficacy for the tested bacteria, A. hydrophila and E. ictaluri.