Preparation, physicochemical characterization and functional properties of selenium nanoparticles stabilized by polysaccharides from the seeds of Plantago asiatica L.

Background: Selenium nanoparticles (SeNPs), comprising a novel selenium element with higher bioactivity, easily aggregate into large black monomeric selenium particles. In the present study, polysaccharides from the seeds of Plantago asiatica L. (PLP) was used as a template and morphology/particle size modifier to synthesize selenium nanoparticles. The preparation process of SeNPs stabilized by PLP was optimized, and its antioxidant and immunological activities were investigated.

Results: The optimal preparation conditions of PLP-SeNPs were a reaction temperature of 60°C, a reaction time of 1.5 h, a PLP concentration of 0.04 mg · mL and a NaSeO/Vc molar ratio of 1:5. Stable spherical PLP-SeNPs with a particle size of 78.39 ± 2.15 nm were prepared through this process. The PLP-SeNPs complex at a concentration of 32 μg · mL demonstrated scavenging activities against 1,1-diphenyl-2-picrylhydrazyl radicals, hydroxyl radicals and 2,2'-azinobis-(3-ethyl-benzothiazolin-6-sulfonic acid) diammonium salt radicals of up to 49.49 ± 2.58%, 60.99 ± 2.49% and 42.07 ± 1.76%, respectively. The PLP-SeNPs complex significantly increased the activation of RAW264.7 cells through improving phagocytosis, reactive oxygen species levels, and the secretion of tumor necrosis factor-α and interleukin-10.

Conclusion: The present study lays a theoretical foundation for the development of food-borne SeNPs and the exploration of their application in functional foods, which will help to promote the high-value utilization of P. asiatica L., and also has an important guiding significance for the healthy development of selenium-enriched functional food industry. © 2025 Society of Chemical Industry.