fa عمومى General كاربردي Applicable <span style="font-size:11pt"><span style="line-height:85%"><span style="font-family:Calibri,sans-serif"><span lang="TR" style="font-size:12.0pt"><span style="line-height:85%"><span style="font-family:&quot;Times New Roman&quot;,serif"><span style="color:black">Bacterial biofilms make pathogen control in aquaculture more difficult because the extracellular matrix can protect cells and reduce their response to antimicrobial treatment. Quorum quenching has been studied as a way to reduce biofilm formation and virulence without directly killing bacterial cells. This study screened three cultivable bacteria associated with marine macroalgae for quorum-sensing inhibition and anti-biofilm activity. Strains 1 and 2 were isolated from <i>Acanthophora</i> sp., while Strain 3 was isolated from <i>Caulerpa </i>sp. Quorum-sensing inhibition was tested using the <i>Chromobacterium violaceum</i> CV026 biosensor. Cell-free supernatants (CFSs) were tested against <i>Pseudomonas aeruginosa</i> biofilms using crystal violet staining. None of the three isolates produced a detectable response in the CV026 assay across three screening runs. In the biofilm assay, Strain 3 CFS showed a 98.95% reduction in retained <i>P. aeruginosa</i> biofilm biomass compared with the untreated control. Strains 1 and 2 showed inhibition values of &minus;24.11% and &minus;3.74%, respectively. These results show that the three isolates exhibited different effects on <i>P. aeruginosa</i> biofilm biomass. Strain 3 showed the strongest anti-biofilm effect, and Strains 1 and 2 did not reduce retained biofilm biomass. The different responses also show that biofilm activity may depend on the bacterial isolate and the compounds released into the CFS. Strain 3 can therefore be selected for taxonomic identification and further study to determine the compounds linked to its anti-biofilm activity. Overall, the study identified Strain 3 as the most promising isolate for further research work on biofilm control in aquaculture-related bacterial pathogens and other similar applications.</span></span></span></span></span></span></span><br> &nbsp; Anti-biofilm activity quorum-sensing inhibition, Macroalgae-associated bacteria, Chromobacterium violaceu, Pseudomonas aeruginosa, Aquaculture 143 154 http://injbir.com/browse.php?a_code=A-10-1-56&slc_lang=fa&sid=1 H.T. Tan 1003194753284600755 1003194753284600755 Yes Center of Excellence for Research, Value Innovation and Entrepreneurship (CERVIE), UCSI University, Cheras 56000, Kuala Lumpur, Malaysia H.T.J. Chai 1003194753284600756 1003194753284600756 No Faculty of Applied Sciences, UCSI University, No 1, Jalan UCSI, UCSI Heights, 56000 Cheras, Kuala Lumpur, Malaysia J. Suresh 1003194753284600757 1003194753284600757 No Faculty of Applied Sciences, UCSI University, No 1, Jalan UCSI, UCSI Heights, 56000 Cheras, Kuala Lumpur, Malaysia Y.Y. Lau 1003194753284600758 1003194753284600758 No Faculty of Applied Sciences, UCSI University, No 1, Jalan UCSI, UCSI Heights, 56000 Cheras, Kuala Lumpur, Malaysia S.M. Phang 1003194753284600759 1003194753284600759 No Faculty of Applied Sciences, UCSI University, No 1, Jalan UCSI, UCSI Heights, 56000 Cheras, Kuala Lumpur, Malaysia M. Khaledi 1003194753284600760 1003194753284600760 No Department of Pharmaceutical Chemistry, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran M.J. Hessami 1003194753284600761 1003194753284600761 No Faculty of Applied Sciences, UCSI University, No 1, Jalan UCSI, UCSI Heights, 56000 Cheras, Kuala Lumpur, Malaysia