Investigation on relationships between chemical spectrum and bioeffect of prepared rhubarb decoction in rats by UPLC-ESI-Q-TOF-MS method coupled with gray correlation analysis

Prepared rhubarb is obtained by steaming raw rhubarb with glutinous rice wine. To explore the chemical material basis and functional mechanism of prepared rhubarb, an ultra-performance liquid chromatography-quadrupole-time of flight-mass spectrometry coupled with gray correlation analysis statistical method was developed. Finally, 19 compounds in rat plasma were detected after oral administration of prepared rhubarb decoction. It was found that 9 of them were the original form of compounds in prepared rhubarb, and the other 10 were the relative metabolites. Taking bioeffects-time curves into consideration as well, gray correlation analysis were performed. The ranking of these 19 compounds was given out basing on their respective contribution to the drug bioeffect. Rhein glucuronide was eventually found possessing the highest possibility to be the main active ingredient for treatment of noxious heat with blood stasis syndrome.