[Research on extraction process of Digeda-4 flavored decoction based on QbD concept].

To establish and validate the design space of the Digeda-4 flavored decoction( DGD-4D) extraction process by using the quality by design( Qb D) concept. With DGD-4D decoction pieces as a model drug,with the transfer rate of aesculin,picroside I,picroside Ⅱ,geniposide and the yield of extract as critical quality attributes( CQAs),the single factor experiment design was used to determine the level of each factor; the Plackett-Burman experiment design was used to select the critical process parameters( CPPs);and the Box-Behnken experiment design was used to optimize the extraction process. The design space of the DGD-4D extraction process was established,and finally,four experimental points were selected to verify the established model.