Metabolites of salvianolic acid C in rats in vivo

The objective of this study was to separate and identify the metabolites in rat plasma and urine after oral administration of salvianolic acid C, a phenolic acid in Salvia miltiorrhiza(Danshen). Solid-phase extraction method with strong anion exchange was used to separate the metabolites from the biological matrix. High-performance liquid chromatography coupled with electrospray quadrupole time-of-flight tandem mass spectrometry(HPLC-ESI/Q-TOF MS/MS)analysis was performed to identify the metabolites. Five metabolites were identified as caffeic acid(M1), monomethyl-salvianolic acid C-monoglucuronide(M2), dimethyl-salvianolic acid C-monoglucuronide(M3), dimethyl-salvianolic acid C-monoglucuronide(M4), dimethyl-salvianolic acid C(M5), as well as the prototype of salvianolic acid C detected in plasma and urine. The results indicated that methylation and glucuronidation might be the two main metabolic pathways of salvianolic acid C.