Optimization of polysaccharides extraction from Dictyophora indusiata and determination of its antioxidant activity.

Response surface methodology (RSM) was used to optimize the extraction conditions of polysaccharides from the fruiting body of Dictyophora indusiata (DIP). Effect of extraction time, extraction temperature and solid to liquid ratio on the yield of DIP was investigated. The optimum extraction conditions for DIP were as follows: extraction time, 2.1h, solid to liquid ratio, 1:37, and extraction temperature, 92°C. Under these conditions, the experimental extraction yield of DIP was 15.95±0.144%, which was matched closely to the predicted value. During the antioxidant experiments in vitro, DIP exhibited a strong reducing capacity and strong scavenging activity on DPPH, superoxide, and hydroxyl radicals. The EC50 of DIP on DPPH, hydroxyl and superoxide radicals was 0.89mg/L, 0.51mg/mL and 0.68mg/mL, respectively. This suggests that polysaccharides from D. indusiata have the potential to be the resources of natural antioxidants.