Versatile inulin/trans-ferulic acid/silk sericin nanoparticles-nourished probiotic complex with prolonged intestinal retention for synergistic therapy of inflammatory bowel disease.

To achieve effective long-term synergistic treatment of inflammatory bowel disease (IBD) with probiotics, we developed a versatile inulin/trans-ferulic acid/silk sericin nanoparticles-nourished probiotic complex. Inulin/TFA/SS nanoparticles were fabricated by inulin, trans-ferulic acid (TFA), and silk sericin (SS), and then loaded onto the surface of poly-l-lysine (PLL) and poly-glutamic acid (PGA)-coated Bifidobacterium longum (BL) to obtain BL@PLL-PGA-Inulin/TFA/SS NPs (BL@PP-NPs). This design simultaneously endowed the complex with excellent gastrointestinal resistance, antioxidant, and anti-inflammation abilities. Moreover, the inulin in the nanoparticles acts as a prebiotic, promoting the Bifidobacterium's rapid proliferation to exert effects within a short period. Compared with uncoated BL, BL@PP-NPs exhibited excellent gastric acid tolerance and up to 31.32-fold colonic colonization, and the ROS scavenging and proliferative capacity were increased by 5.61- and 1.39-fold, respectively. In a mouse model of dextran sulfate sodium (DSS)- and trinitrobenzene sulfonic acid (TNBS)-induced colitis, the components of Inulin/TFA/SS NPs synergized with probiotics to efficiently treat IBD by attenuating oxidative stress, decreasing inflammation, repairing intestinal barrier, and promoting the rapid proliferation of probiotics to reverse gut microbial disorders. Collectively, food-grade BL@PP-NPs represent a novel approach to probiotic modification that offers an effective, safe, and synergistic therapy for IBD.