Extraction, purification, and biological activities in vivo of a novel fructose-rich polysaccharide from Codonopsis pilosula

The Codonopsis pilosula polysaccharide have been widely extracted through water dissolution and ethanol precipitation, and presented immunoregulatory and antioxidant activities. However, the polysaccharide from the supernatant was always discarded and rarely reported. In the present study, the extraction process, preliminary structural characteristics, immunoregulatory and antioxidant activities in vivo of C. pilosula polysaccharide prepared from the supernatant after 80% ethanol precipitation were evaluated and analyzed. Results showed that the optimized conditions for fructose-rich polysaccharide (Fru/Glc ratio of 2.73:1.00 with average molecular weight of 3.24 × 103 Da) extraction were determined as follows: liquid to material ratio of 40 mL/g, extraction time of 60 min, ultrasonic power of 370 W, and extraction temperature of 60 °C, and the yields reached to 6.52 ± 0.36%. Animal experiments demonstrated that the polysaccharide could effectively protect the immune organs, enhance the immune cells activities, and improve the leukocytes amounts and the expression levels of immune-related cytokines dose-dependently in CTX-treated mice, which was mainly attributed to the enhancement of antioxidant enzymatic activities and suppression of oxidative damage. These results suggested that the polysaccharide had the potential to be a natural antioxidant supplement due to the feasibility of industrial production and practical application.