Selenized Polysaccharides From Acanthopanax leucorrhizus: Synthesis, Characterization, and Cytotoxicity

Selenylation modification has been extensively developed as a method to enhance the biological effects of natural polysaccharides. In this study, a novel water-soluble polysaccharide, designated as ALPS-41, was isolated from the stem bark of A. leucorrhizus and subsequently selenized to form Se-ALPS-41, using the HNO₃-Na₂SeO₃ method. The physicochemical properties and structural features of both ALPS-41 and Se-ALPS-41 were thoroughly characterized, using UV, Fourier transform infrared (FT-IR), high-performance gel-permeation chromatography (HPGPC), HPLC, scanning electron microscopy (SEM), X-ray diffraction (XRD), and NMR analyses. In vitro cytotoxicity was evaluated via Cell Counting Kit-8 (CCK-8) assays against human MCF-7, HeLa, HepG2, and HEK293 cell lines. Chemical composition analysis revealed that the homogeneous ALPS-41 had an average molecular weight of 437 kDa and was composed of glucose, galactose, and mannose in a molar ratio of 2.21:1.58:1.00. The selenium content and molecular weight of Se-ALPS-41 were determined to be 87.56 mg/g and 298 kDa, respectively. Cytotoxicity tests demonstrated that Se-ALPS-41 decreased the viability of MCF-7 and HepG2 cells in a concentration-dependent manner, while exhibiting no cytotoxic effect on HeLa and normal HEK293 cells. These findings suggest that selenium-modified polysaccharides derived from A. leucorrhizus may serve as a potential selenium source with antitumor properties.