In Vitro Antimicrobial and Antibiofilm Activity of S-(-)-Limonene and R-(+)-Limonene against Fish Bacteria

Brazilian fish farming goes together with the emergence of numerous bacterial diseases, Aeromonas hydrophila being main pathogen. As a consequence, antimicrobials are excessively used. Considering that relatively stable and nonbiodegradable, medicinal plants their phytochemicals have been used as alternative treatments bacteriosis in farming. Limonene is monoterpene available two enantiomers: R-(+)-limonene S-(-)-limonene. This study analyzed antibacterial activity S-(-)-limonene against some bacteria isolated from silver catfish (Rhamdia quelen). Furthermore, by means spectrophotometry atomic force microscopy, we also investigated combination therapy terms inhibiting biofilm formation. Six clinical isolates standard strain were selected for antimicrobial testing. Biofilm formation was tested 96-well plates nylon cubes. The most sensitive strains A. (MF 372510). had high minimum inhibitory concentrations; however, they strongly inhibited an additive effect when combined florfenicol antagonistic oxytetracycline. In general, showed strong antibiofilm hydrophila, florfenicol, treatment hydrophila.