Marine-Derived Bacillus Biosurfactants as Potential Antibacterial and Antibiofilm Agents Against Oral Pathogens

The growing antimicrobial resistance (AMR) is threatening traditional treatments for oral diseases like dental caries and periodontitis, which constitute a significant global health burden. The study aimed to isolate <i>Bacillus</i> species from marine samples, to assess their biosurfactant-producing capabilities, and to evaluate their antibacterial activity against oral pathogens. <i>Bacillus</i> strains were isolated from marine water and sediment samples, identified by phenotypic and genotypic methods, and screened for their biosurfactant-producing ability by drop collapse, hemolytic activity, bacterial adhesion to hydrocarbons (BATH), oil displacement, and emulsification assays. Ethyl acetate extracts of these <i>Bacillus</i> strains were tested for antibacterial efficacy against four oral pathogens (MTCC strains) by the agar-well diffusion method. Among 81 bacterial isolates, 13 were confirmed as <i>Bacillus</i> species by phenotypic and 16S rRNA gene sequencing. Six <i>Bacillus</i> isolates displayed significant antibacterial activity, and the majority were beta-hemolytic. <i>Bacillus</i> strain TVD12 (50 mg/mL) exhibited superior performance by inhibiting <i>S. mutans</i> (31 mm ± 0)<i>, S. anginosus</i> (30.5 mm ± 0.7), <i>S. aureus</i> (20 mm ± 1.4), and <i>E. faecalis</i> (29 mm ± 4.24). <i>Bacillus</i> strain TVW12 (500 μg/mL) performs better in antibiofilm activity by inhibiting <i>E. faecalis</i> 90%, <i>S. aureus</i> 87.4%, and <i>S. mutans</i> 76.8%. Statistical analysis revealed a distinct dual-activity profile, characterized by consistent broad-spectrum antimicrobial efficacy (<i>p</i> = 0.809) alongside specialized, pathogen-specific antibiofilm inhibition (<i>p</i> = 0.004). Marine-derived <i>Bacillus</i> strains, such as TVW12, and TVD12 demonstrated effective antibacterial and antibiofilm properties, offering a feasible approach to combat oral pathogens, contributing to sustainable development goals (SDGs) by addressing the challenges of antimicrobial resistance (SDG 3) through sustainable marine bioprospecting (SDG 14). These findings suggest their possibility in developing novel antibacterial agents against oral pathogens in future therapeutic applications.