Modulation of the salivary microbiome using deep-sea marine bacterial strains: A pilot study.

Background: The oral microbiome is a critical determinant of both local and systemic health. Dysbiosis, particularly the overgrowth of pathogenic taxa, is implicated in various oral diseases and may contribute to extraoral inflammatory conditions. Although probiotics derived from gut commensals have shown some efficacy, their application to the oral cavity is limited by environmental incompatibility. Marine bacteria, especially those adapted to extreme environments, offer a novel therapeutic avenue due to their inherent antimicrobial and biofilm-disruptive properties. Aim: This pilot study investigated the potential of deep-sea marine bacterial strains- Methods: A randomized, controlled, two-arm parallel design was employed involving 20 healthy adult participants. Subjects were assigned either to a Treatment Group (n = 10), receiving a marine-derived bacterial mouthwash for seven days, or a Control Group (n = 10) with no intervention. Unstimulated saliva samples were collected at baseline and post-intervention. Microbial profiling was conducted using 16S rRNA gene sequencing and species-specific quantitative PCR. Analyses included paired t-tests, Principal Component Analysis (PCA), and microbial network inference to assess changes in microbial abundance and community structure. Results: The Treatment Group demonstrated statistically significant reductions in Conclusion: The application of marine-derived bacterial strains was associated with favorable modulation of the oral microbiome, including suppression of key pathogens and enhancement of beneficial taxa. While preliminary, these findings highlight the therapeutic promise of marine probiotics as a biologically selective and ecologically supportive approach to oral health. Larger, placebo-controlled studies are warranted to confirm efficacy, assess long-term effects, and evaluate clinical outcomes.