Preliminary structure, antioxidant and immunostimulatory activities of a polysaccharide fraction from Artemisia selengensis Turcz.

Artemisia selengensis Turcz possesses various health-promoting functions. However, the available information regarding the structure and biological activity of polysaccharides from A. selengensis Turcz (APS) is still limited. In the present study, the preliminary structure, antioxidant and immunostimulatory activities of a polysaccharide fraction from APS (APS1) were investigated. Results of Fourier transform-infrared spectroscopy (FT-IR), gas chromatography-mass spectrometry (GC-MS) and nuclear magnetic resonance (NMR) analyses showed that the main chain of APS1 was made up of T-α-D-Glcp-(1→, →4)-α-D-Glcp-(1→ and →4)-α-D-Galp-(1→ residues). In addition, the moderate superoxide and ABTS radical scavenging activities and noticeable Fe²⁺ chelating activity of APS1 were observed. Furthermore, the administration of APS1 could significantly restore spleen and thymus indexes, increase the levels of serum hemolysin and lysozyme, and improve the liver function by remarkably preventing the elevation of MDA level and increasing the levels of catalase (CAT), total antioxidant capacity (T-AOC), superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) in cyclophosphamide-treated mice. These results suggested that APS1 exhibits antioxidant and immunostimulatory activities with potential application in functional foods.