Objective: We are interested in the metabolism of baicalin in human body to offer more information to clinic.
Method: Urine of ten persons was collected during 2-18 h after taking 1.0 g of baicalin orally, and the urine was concentrated to 0.5 L, then filtered, the solution being loaded on an iron exchange column eluted with 1.0 L of H2O and 1.0 L of 50% EtOH. The EtOH fraction was concentrated and loaded on a Sephadex LH 20 column eluted with 0.5 L of H2O to obtain 15 fractions, which were detected by silica gel TLC (CHCl3-MeOH-H2O, 1:1:0.1). The fractions 8-11 showed flavonoid characteristics by spraying FeCl3 reagent, and the four fractions were combined to obtain the sample containing metabolites of baicalin for HPLC analysis and LCMS measurement.
Results and conclusions: M1, M2 and M3 was identified as baicalein-6-O-beta-glucopyranuronoside; 6-O-methyl-baicalin-7-O-beta-glucopyranuronoside and baicalin.