Study on optimization of extraction of total flavonoids from Dictyophora indusiata Fisch. by supercritical CO2 and its antioxidant activity

The effect of extraction temperature, CO2 flow rate, extraction pressure, extraction time, entrainer volumes, types and amounts of separation solvents on the extraction yield of total flavonoids from Dictyophora indusiata Fisch. was investigated by single factor test in this study. The supercritical CO2 extraction conditions were further optimized by the response surface analysis and were determined to be extraction temperature of 40℃, CO2 flow rate of 10L/h, extraction pressure of 35.5MPa and extraction time of 122 min. Under the optimal extraction conditions, the yield of total flavonoids from Dictyophora indusiata Fisch. reached 3.6mg/g by adding2∶1 (V:m) 95% ethanol and then adding 1∶4 (V∶V) petroleum ether. Result of antioxidation showed that the total flavonoids from Dictyophora indusiata Fisch. had good total reduction capabilities, and scavenging hydroxyl radicals, DPPH, superoxide anion (O2-·) , it had good antioxidant activity.