Metabolism of Constituents in Huangqin-Tang, a Prescription in Traditional Chinese Medicine, by Human Intestinal Flora

Comparative pharmacokinetics of baicalin and wogonoside by liquid chromatography–mass spectrometry after oral administration of Xiaochaihu Tang and Radix scutellariae extract to rats

“…3. This phenomenon was similar to that in other reports [25][26][27], and was probably due to enterohepatic circulation. The main pharmacokinetic parameters after oral administration of Radix scutellariae extract have been reported by Shi et al [28].…”

“…* p < 0.05 by the small intestinal mucosa was partly transformed into baicalin by UDP-glucuronosyltransferase(UGT), which was then partly absorbed into the blood [27,35,36]. Baicalein was partly absorbed into the blood directly and transformed into baicalin or metabo- lized by hepatic microsomal enzymes [18,26,37], and baicalein was the main metabolite of baicalin in vivo. In our study, we found a peak (named M) with a retention time of about 5 min at m/z 461 was similar to wogonoside (m/z 461) after oral administration of Xiaochaihu Tang and Radix scutellariae extract ( Fig.…”

Skullcap Scutellaria lateriflora L.: An American nervine

“…Elimination halftimes (T 1/2 [K e ]) ranged from 3.55 h for baicalin to 27.37 h for oroxylin A-7-O-glucuronide. Concerning their metabolism, researchers have pointed out that a cleavage of the sugar moiety of baicalin, wogonin-7-O-glucuronide, and oroxylin A-7-O-glucuronide by the intestinal flora in rats and humans occurs (Akao et al, 2000;Zuo et al, 2002Zuo et al, , 2003. While baicalein is readily absorbed in the intestine, it is extensively metabolized to baicalin in the intestinal mucosa cells, and there is evidence that baicalin undergoes enterohepatic circulation after oral administration in rats (Xing et al, 2005).…”

Liquid chromatography with tandem mass spectrometry for the simultaneous determination of baicalein, baicalin, oroxylin A and wogonin in rat plasma

“…The absorption, metabolism and excretion studies of pure baicalein and baicalin [15][16][17][18]29], or wogonin [19][20][21] in rats and humans were evaluated. A few pharmacokinetics data of baicalein, baicalin, wogonin and/or oroxylin A after oral administration of Scutellariae radix or medicinal preparations were available [22][23][24][25][26]. Selective and sensitive analytical method for the simultaneous determination of baicalein, baicalin, oroxylin A and wogonin in plasma is needed in order to characterize the pharmacokinetics of baicalein, baicalin, oroxyiln A and wogonin after administration of Scutellariae radix extracts.…”