Abstract:The uniform extraction method was used to optimize the ultrasonic extraction technology parameters of Grifola frondosa polysaccharides，which provided a reference for the development and utilization of polysaccharide resources.Took the extraction rate of polysaccharide and β-glucan from Grifola frondosa as the evaluation index，and took the ultrasonic power，extraction time，extraction temperature and water-to-material ratio as factors，the extraction process was optimized by uniform design method，and the antioxidant activity of Grifola frondosa polysaccharide was also evaluated.The results showed that the optimal conditions for ultrasonic extraction of Grifola frondosa polysaccharides were ultrasonic power of 500 W，extraction time of 64 min，extraction temperature of 43 ℃，water-to-material ratio of 31∶1（mL/g），and two extraction times.Under these conditions，the extraction rate of Grifola frondosa polysaccharides from filaments was 23.055%. The optimal extraction conditions for β-glucan were ultrasonic power of 450 W，extraction time of 74 min，extraction temperature of 68 ℃and water-to-material ratio of 28∶1（mL/g）.Under these conditions，the extraction rate of β-glucan was 3.030 mg/g.The antioxidant activity research results showed that the reducing power OD700 nm value of Grifola frondosa polysaccharide was 0.561±0.005，and its DPPH radical and hydroxyl radical scavenging rates were both as the mass concentration increased，the scavenging rates of DPPH and hydroxyl radicals were 58.27%and 89.58%，respectively.The scavenging rates of hydroxyl radicals were higher than those of VC.