Abstract:The ultrasound-assisted deep eutectic solvents（DES）-based extraction of polysaccharides from Phellinus igniarius was optimized with the yield of polysaccharides as the indicator.Single factor test and Box-Behnken design were employed to investigate the effect of the molar ratio of DES，water content of DES，liquidto-solid ratio，ultrasonic power，ultrasonic time，and extraction temperature on the yield of polysaccharides and optimize the extraction process.The DPPH and hydroxyl free radical scavenging rates and the inhibition rate on tumor cells in vitro were explored.The extraction process was optimized as choline chloride and glycerol at the molar ratio of1 ∶2，water content of 30% in DES，ultrasonic time of 30min，liquid-to-solid ratio of39 ∶1（mL/g），extraction temperature of 58℃，and ultrasonic power of 90 W.Under these conditions，the yield of polysaccharides was（13.11±0.16）%，which showed the relative error of 0.91% compared with the predicted value.The purified polysaccharides exerted the antioxidant activity and tumor cell proliferation-inhibiting ability in a dosedependent manner.Ultrasound-assisted DES-based extraction of polysaccharides from P.igniarius has high yield of polysaccharides.Moreover，the extracted polysaccharides have strong antioxidant and antitumor activities.