Fabricating Blackened Jujube Polysaccharide‐Zn (II) Complex to Enhance its Anti‐Inflammatory Effect: Structural Characterization and Biological Evaluation

Polysaccharides extracted from blackened jujubes (BP) demonstrate remarkable pharmacological activities. Chelation with zinc ions represents an effective strategy for enhancing their biological functions. In this study, a novel polysaccharide-Zn (II) complex derived from blackened jujube (BP-Zn) was successfully synthesized, and its structural characteristics as well as anti-inflammatory effects were comprehensively evaluated in a dextran sulfate sodium (DSS)‑induced colitis model. The results indicated that -OH and -COOH groups in BP interacted with zinc ions through ligand bonds. Zinc chelation enhances the structural stability and molecular properties of BP. The BP-Zn complex demonstrated significant anti-inflammatory properties by a reduction in body weight loss, an increased thymus index, and the restoration of intestinal barrier integrity. Furthermore, microbiome analysis revealed that the BP-Zn complex modulated the gut microbiota, boosting beneficial bacteria while inhibiting pathogenic species. Metabolomic profiling demonstrated that BP-Zn modulated key metabolic pathways involved in inflammation and immune regulation, particularly amino acid and flavonoid metabolism. These results suggested that BP-Zn complex has strong potential as natural anti-inflammatory agents.