Seaweed Extracts as an Effective Gateway in the Search for Novel Antibiofilm Agents against .

Treatment of biofilm-associated infections has become a major challenge in biomedical and clinical fields due to the failure of conventional treatments in controlling this highly complex and tolerant structure. Therefore, the search for novel antibiofilm agents with increased efficacy as those provided by natural products, presents an urgent need. The aim of this study was to explore extracts derived from three algae (green , brown , red ) for their potential antibiofilm activity against , bacterium responsible for several acute and chronic infections. Seaweed extracts were prepared by successive maceration in various solvents (cyclohexane (CH), dichloromethane (DCM), ethyl acetate (EA), and methanol (MeOH)). The ability of the different extracts to inhibit biofilm formation was assessed using colony-forming unit (CFU) counts method supported by epifluorescence microscopic analysis. Effects of active extracts on the biofilm growth cycle, as well as on surface hydrophobicity were evaluated. Results revealed the ability of four extracts to significantly inhibit biofilm formation. These findings were supported by microscopy analyses. The gradual increase in the number of adherent bacteria when the selected extracts were added at various times (t, t, t, t, and t) revealed their potential effect on the initial adhesion and proliferation stages of biofilm development. Interestingly, a significant reduction in the surface hydrophobicity of treated with dichloromethane (DCM) extract derived from was demonstrated. These findings present new insights into the exploration of seaweeds as a valuable source of antibiofilm agents with preventive effect by inhibiting and/or delaying biofilm formation.