Objective: To optimize ultrafiltration purification technology parameters of Gegen Qinlian extract. Method: With composite score of transfer rates of puerarin

baicalin

berberine hydrochloride and ammonium glycyrrhetate as index

orthogonal test was adopted to optimize purification technology of Gegen Qinlian extract by taking ultrafiltration pressure

liquid temperature and solvent amount as factors. Result: Hollow-fiber membrane with 5000 relative molecular weight had better separation efficiency as others

optimum ultrafiltration technology parameters were as follow:ultrafiltration pressure 0.025 MPa

liquid temperature 40 ℃

2 times the amount of solvent;Transfer rates of puerarin

baicalin

berberine hydrochloride and ammonium glycyrrhetate were 82.78%(RSD 2.76%)

88.63%(RSD 1.43%)

89.75%(RSD 2.52%)

59.91%(RSD 1.97%). Conclusion: Hollow-fiber membrane could be selectively used in purification of liquid

it could increase retention rate of active ingredient in Gegen Qinlian extract.