Abstract: In order to optimize the extraction yield of total flavonoids in Potentilla parvifolia leaves,the optimal extraction process was determined.Based on the single factor experiment,ethanol concentration,material-liquid yield and extraction temperature were selected as independent variables,and the total flavonoid extraction yield and antioxidant capacity were used as the response values.The Box-Behnken center combined experimental design was carried out,and the response surface methodology (RSM) was used to evaluate the effects of the above factors on the extraction yield and antioxidant capacity of total flavonoids.The results showed that the optimum extraction conditions of total flavonoids were ethanol concentration of 51%,material-liquid yield of 30∶1 (mL/g),extraction temperature of 80 ℃.Under these conditions,the total flavonoids extraction yield was 2.83%,the anti-oxidant capacity was 16.37%.The extraction process optimized by RSM was reasonable and reliable.And it could be used for optimal control of flavonoid extraction process in leaves of Potentilla parvifolia.

Key words: Potentilla parvifolia, total flavonoids, anti-oxidation, RSM