Li Wenlan

Identification of the chemical constituents of bazhen decoction in rat feces by high performance liquid chromatography electro spray ionization mass spectrometry (HPLC-ESI/MS) n

A high performance liquid chromatography/mass spectrometry (HPLC/MS) was developed for the identification of rat feces in metabolites of the bazhen decoction. The metabolites were separated using gradient elution with mobile phase of 0.15% formic acid and acetonitrile. Blank and drug-containing feces samples were detected in the negative electrospray ionization, scan scope was 100 to 1200 andxa0total ion currentxa0(TIC) chromatography was recorded. 29 major fragment ion peaks were marked in the TIC chromatogram of feces sample after the intragastric administration of bazhen decoction. According to the characteristic of fragmentation information, we identified 19 chemical constituents, including 10 prototype constituents: Paeoniflorin, Atractylenolide II, Benzoyl-paeoniflorin, Liquiritin, Pachymic acid, Ginsenoside Re, Ginsenoside Rg1, Ginsenoside Rb1, Ginsenoside Rd and Glycyrrhizic acid and 9 metabolites: Paeonimetabolin I, Aucubinine A, 20-O-β-D-glucopyranosyl-20 (S)-protopanaxadiol, 20 (S)-Protopanaxatriol, 16α-hydroxy acids perforation, 20 (S)-Protopanaxadiol, Licorice saponine, 18β-Glycyrrhetinic acid and Ginsenoside Rh1. The results show that the final metabolites in rat feces of bazhen decoction are quite valuable for the further studies on material basis of efficacy and clinical application of bazhen decoction. n n xa0 n n Key words:xa0Bazhen decoction, high performance liquid chromatography/mass spectrometryxa0HPLC-ESI/MS, metabolites, feces.