Characterization of polysaccharides with antioxidant and immunological activities from Rhizoma Acori Tatarinowii

Rhizoma Acori Tatarinowii is widely used in traditional Chinese medicine. In this study, three novel polysaccharides designated RATPW, RATPS1 and RATPS2 were isolated from Rhizoma Acori Tatarinowii by DEAE-52 cellulose chromatography. Their structures were characterized using physicochemical and spectral methods. Chemical analysis indicated that RATPW (6.5 × 103 Da) mainly composed of glucose and fructose. RATPS1 (1.5 × 105 Da) contained galactose and arabinose, while RATPS2 (5.3 × 104 Da) contained ∼49.5% galacturonic acid along with rhamnose, fructose, galactose, and arabinose. In vitro, RATPS2 showed the most significant scavenging activity on DPPH and hydroxyl radical. Three polysaccharides could protect the PC12 cells from H2O2-induced damage. Immunological tests indicated that both RATPW and RATPS2 significantly stimulated NO production and phagocytic activity in RAW264.7, and promoted splenocyte proliferation. These data suggested that polysaccharides RATPW and RATPS2 had the potential as novel natural sources of antioxidative and immunopotentiating agents.