Extraction, Characterization, Antioxidant, and Immunostimulatory Activities of Polysaccharides from Hedyotis corymbosa

In this study, optimization of enzyme-assisted extraction, purification, characterization, and its bioactivities of polysaccharides from (HCP) was investigated. It was found that the optimum extraction conditions were 3% of enzyme concentration ( ), 30 of liquid-to-solid ratio ( ), 56°C of extraction temperature ( ), 200W of ultrasonic power ( ), 10 min of extraction time ), and 5 of pH value ( ). Under optimum conditions, the experimental yield (4.10 ± 0.16%) was closed to the predicted value (4.02%). The crude HCP was further purified using DEAE-52 and Sephadex G-150 gel column, and a major polysaccharide fraction from HCP, designed as HCP-1a with molecular weight of 33.9 kDa, was obtained. The HCP and HCP-1a were characterized by chemical analysis, FT-IR, and HPLC. For antioxidant activities , HCP possessed strong hydroxyl radical scavenging, DPPH radical scavenging, and Fe chelating activities. In subsequent immunostimulatory studies, significantly decreased NO, IL-1, and TNF- concentrations were observed in both of HCP and HCP-1a treated RAW264.7 cells. Therefore, this study may indicate some insights into the application of polysaccharides from as potential natural antioxidants and immunostimulants.