Probiotic potential of novel Lactobacillus and Limosilactobacillus isolated from Formosan pangolin feces

BACKGROUND: The critically endangered Formosan pangolin (Manis pentadactyla pentadactyla) faces severe conservation challenges, with gastrointestinal (GI) disorders being a primary driver of mortality in captivity. These ailments are often exacerbated by dietary transitions and anthropogenic stress. While the gut microbiota is crucial for host health, the probiotic potential of the pangolin’s native microbes remains unexplored. This study aimd to isolate lactic acid bacteria (LAB) from wild pangolin feces and preliminarily characterize their probiotic properties. RESULTS: Ten LAB strains with < 97.3% 16S rRNA gene similarity to known species likely represent undescribed lineages within Lactobacillus and Limosilactobacillus. Phylogenetic analysis revealed two clusters: three Lactobacillus strains related to L. jensenii and L. psittaci, and seven Limosilactobacillus strains close to L. fermentum. All isolates showed strong acid and bile tolerance and high cell surface hydrophobicity (> 90%). The Lactobacillus cluster exhibited superior auto-aggregation (> 80%), pathogen co-aggregation, and organic acid-mediated antibacterial activity, along with cellular component-driven inhibition of α-glucosidase (66.5–69.4%) and α-amylase (75.8–77.2%). In contrast, Limosilactobacillus strains demonstrated metabolite-mediated enzyme inhibition (up to 84.1%) and antioxidant activity (25.6–48.2% TAC; 36.3–46.3% DPPH). All isolates were susceptible to cell wall and protein synthesis inhibitors, confirming a safe antibiotic profile. CONCLUSION: These findings identify a reservoir of novel, pangolin-derived LAB with multifaceted probiotic traits. These isolates represent promising candidates for targeted nutritional strategies to mitigate GI distress and improve the survival of this endangered mammal. This work bridges the gap between microbial ecology and practical wildlife conservation, offering a scientific basis for enhancing the health of captive pangolin populations.