Snake Gut Microbiota as a Source of Anti-Inflammatory Probiotics: Isolation and Functional Characterization of Two Novel Strains.

The intestinal microbiome is fundamental to host physiological homeostasis, while deviations from its balanced state have been linked to inflammatory bowel diseases (IBD). To address the limitations of conventional antibiotic therapies, this study explored snake gut microbiota as a novel source of anti-inflammatory probiotics. We explored the gut microbiota of five snake species (Deinagkistrodon acutus, Trimerodytes annularis, Trimerodytes percarinatus, Lycodon rufozonatus, and Trimeresurus stejnegeri) through metagenomic sequencing. Community composition analysis revealed that the phylum-level composition was mainly Proteobacteria, Bacteroidetes, Actinomycetota, and Firmicutes. We further detected some potential probiotic species, such as Enterococcus, Lactobacillus, and Limosilactobacillus. From 196 isolated strains, Lactobacillus johnsonii DA0116 and Limosilactobacillus reuteri DA0218 were selected through rigorous safety and functional assessments, including acid/bile tolerance, pathogen inhibition, and adhesion capacity. In a DSS-induced murine colitis model, both strains significantly reduced disease activity index (DAI), pro-inflammatory cytokines (TNF-α, IL-6, and IL-8), and restored gut microbiota diversity. Additionally, whole-genome analysis identified bacteriocin synthesis clusters (gassericin-S/T) and carbohydrate metabolism genes, explaining their antimicrobial and immunomodulatory properties. This study not only emphasizes the untapped latent value of reptilian gut microbiota for probiotic discovery but also provides two candidate strains with therapeutic promise for IBD and functional food applications.