Protocatechuic acid/sodium alginate multilayer coating induced by metal ion enhanced the ulcerative colitis alleviations of Lactiplantibacillus plantarum.

Oral intake of probiotics is a promising approach to alleviate colitis. However, environmental sensitivity of the gastrointestinal tract and poor adhesion of probiotics to the intestine hamper the remedial effects. In this study, a simple yet effective novel probiotic multilayer coating consisting of Fe3+-protocatechuic acid (PCA) crosslinked network and Ca2+-induced sodium alginate (SA) for arming Lactiplantibacillus plantarum (LP) was developed. In the dextran sulfate sodium-induced colitis mouse model, SA-PCA-LP effectively alleviated colitis by regulating the expression of inflammatory cytokines, and repairing gut barriers. In addition, SA-PCA-LP regulated the gut microbiota and promoted the production of short-chain fatty acids, which further promoted the remission of colitis. Untargeted metabolomics also revealed that the scymnol, adenosine 5'-monophosphat, guanidylic acid, and 9H-purine-9-ol were significantly up-regulated in SA-PCA-LP group. In general, the novel coating strategies developed in the present study will motivate researchers to arm probiotics with various prebiotics to effectively alleviate colitis.