Selenopolysaccharides: advances in synthesis, structural characterization and biological applications

Selenopolysaccharides exhibit potent antioxidant, immunomodulatory and anticancer properties enhancing their biological effectiveness compared to non-selenium variants. Their therapeutic potential in oxidative stress-related disorders is highlighted by improved bioavailability and biocompatibility. This review evaluates selenopolysaccharide research, aiming to resolve issues related to extraction methods, structural characterization and mechanisms that limit their development. Key objectives include analyzing extraction techniques, structural characteristics, biological activities, mechanisms of action and challenges related to clinical applications. In this review, we highlighted the use of various extraction methods and employed spectroscopic and chromatographic analyses. Findings show that microwave-assisted chemical selenylation and nanoparticle synthesis enhance selenium incorporation and bioactivity. Advanced structural analyses revealed diverse selenium valence states affecting functional outcomes. Selenopolysaccharides have potent effects via the MAPK, NF-κB, and TLR signaling pathways, demonstrating synergistic interactions between selenium and polysaccharides. Despite better bioavailability and lower toxicity compared to inorganic selenium, variability in composition and lack of clinical validation hinder their potential. To fully leverage selenopolysaccharides as functional food ingredients and pharmacological agents, it is essential to optimize extraction, elucidate their structures and understand their mechanisms, while addressing concerns regarding standardization, safety and efficacy for their use in managing inflammation, cancer and metabolic disorders.