Combination of bacteriophage and antibiofilm compounds from phyllosphere bacteria as a comprehensive strategy for aquaculture and food pathogen control

Biofilm-forming bacteria, such as Bacillus cereus and Vibrio harveyi are major contributors to food contamination and problems in aquaculture. This study aimed to evaluate the antibiofilm compounds of the phyllosphere bacterial supernatants (Pseudomonas fluorescens JB 3B and Proteus myxofaciens JB 20B), bacteriophages (BC-VP and Vh-S4-phage), and their combinations against these pathogens. Antibacterial and quorum sensing assays showed no activities. The combination of antibiofilm compounds and bacteriophages revealed measurable but species-dependent effects. For B. cereus, the JB 3B-phage and JB 20B-phage combinations revealed inhibition results of 39.21% and 39.62%, and destruction results of 50.60% and 43.12%, respectively. In contrast, V. harveyi showed much lower responses, with inhibition results at 3.49% and 4.80%, and destruction at 9.28% and 6.39%, respectively. SEM analysis supported the microscopic observations, showing reduced biofilm layers and disrupted biofilm matrix structures in treated groups. Gas chromatography - mass spectrometry (GC-MS) analysis showed potential antibiofilm compounds, including acetic acid, sarcosine, 4-octadecenal, and erythritol. Statistical analysis confirmed significant effects of bacterial species, treatment, and the interaction on both biofilm inhibition and destruction (p < .05). Overall, the study highlights specific phyllosphere-derived compounds and bacteriophages with promising antibiofilm activity, while emphasizing that their combined use may not always enhance efficacy in controlling biofilm-related contamination in aquaculture and food industry.