An approach for automated, continuous and rapid extraction of flavonoids from Saussurea medusa Maxim dried cell cultures has been developed in a new-designed dynamic microwave-assisted extraction system. The main factors affecting the extraction process namely power of microwave irradiation, liquid/solid ratio, flow rate of solvent and irradiation time were optimized. The yield of flavonoids reached 4.97% in 60 min under the optimum microwave-assisted extraction conditions: 1200 W of radiation power, 50:1 (v/w) of the liquid/solid ratio, and 50 ml s(-1) of solvent flow rate. The dynamic microwave-assisted extraction showed obvious advantages in short duration and high efficiency to extract flavonoids without causing degradation of target components from the S. medusa dried cell cultures in comparison with the dynamic solvent extraction without microwave assistance. (c) 2006 Elsevier B.V. All rights reserved.