[Determination of four coumarin constituents before and after Angelicae Dahuricae Radix stewed with yellow rice wine and research on its mutual transformation mechanism].

To determine the contents of oxypeucedanin, oxypeucedanin hydrate, byakangelicol and byak-angelicin both before and after Angelicae Dahuricae Radix was stewed with yellow rice wine by high-performance liquid chromatography, and study the mutual transformation mechanisms of oxypeucedanin into oxypeucedanin hydrate, as well as byakangelicol into byak-angelicin. The research results indicated that the contents of oxypeucedanin and byakangelicol were decreased, but the contents of oxypeucedanin hydrate and byak-angelicin were increased after Angelicae Dahuricae Radix was processed with yellow rice wine. The contents' changes of these chemical compounds were due to the ring opening reaction of epoxy compounds, such as oxypeucedanin and byakangelicol under the weak acidity and heating conditions of yellow rice wine. This research could provide a scientific basis for the processing mechanism of Angelicae Dahuricae Radix with yellow rice wine stewing.