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 −1 and a Na 2 SeO 3 /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 −1 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.