Immunomodulatory alginate microcapsules for enhanced delivery of purple sweet potato anthocyanins

Despite the bioactivity of purple sweet potato anthocyanins (IBA), their instability limits their application. To enhance the stability and immunomodulatory efficacy of IBA, novel sodium alginate (SA) microcapsules were developed through interfacial polymerization. The optimized IBA-SA microcapsules exhibited a high encapsulation efficiency and a uniform spherical morphology. Characterization confirmed successful encapsulation and demonstrated significantly improved stability against pH, heat, and light compared to free IBA. In cyclophosphamide-induced immunocompromised mice, the IBA-SA microcapsules restored immune organ indices, enhanced macrophage and NK cell activity, and elevated immunoglobulin levels more effectively than free IBA. Mechanistically, key cytokines (IL-6, TNF-α, IFN-γ) and COX-2 were upregulated, indicating restored immune cell function. These findings demonstrate that IBA-SA microcapsules provide a robust oral delivery system for the development of immune-supporting functional foods and nutraceuticals.

The online version contains supplementary material available at 10.1007/s10068-026-02142-8.