Safety evaluation of Bifidobacterium pseudocatenulatum E−0810 and its synbiotic formulation with xylooligosaccharides in alleviating LPS-induced inflammation in intestinal epithelial cells

Abstract

This study systematically evaluated the safety of the probiotic Bifidobacterium pseudocatenulatum E−0810 and its synergistic anti-inflammatory effects when combined with xylooligosaccharides (XOS). In vitro drug susceptibility tests, hemolysis assays, metabolic product analysis, and cytotoxicity evaluations revealed that the strain exhibited non-transferable resistance to clindamycin, cefixime, ceftriaxone, and rifampicin, while showing no production of hemolysins, indole, or biogenic amines, and demonstrating no cytotoxicity. Whole-genome sequencing confirmed the absence of mobile antibiotic resistance elements, virulence factors, or biogenic amine biosynthesis-related genes in B. pseudocatenulatum E−0810. In vitro fermentation assays demonstrated that XOS significantly enhanced the strain's proliferative capacity and short-chain fatty acid (SCFA) production (P < 0.05). Adhesion assays showed that XOS supplementation markedly increased bacterial adhesion to Caco-2 cells (P < 0.05). In the LPS-induced inflammation model using intestinal epithelial cell line 6 (IEC-6) cells, both B. pseudocatenulatum E−0810 and XOS individually or in combination alleviated intestinal inflammation, with their co-administration exhibiting optimal synergistic efficacy. The E−0810 + XOS combination effectively suppressed LPS-induced oxidative stress and pro-inflammatory cytokine release while restoring mRNA and protein expression levels of tight junction proteins in damaged cells (P < 0.05). Mechanistic studies indicated that this synbiotic formulation exerted intestinal barrier-protective effects by inhibiting the MyD88/NF-κB pathway and activating the Wnt/β-catenin signaling pathway (P < 0.05). These findings indicate that B. pseudocatenulatum E−0810 is a safe probiotic strain, and its synbiotic combination with XOS exhibits anti-inflammatory and gut barrier-protective properties. This study reveals probiotic-prebiotic synergy in regulating gut inflammation, advancing Bifidobacterium-based anti-inflammatory synbiotic development.