“…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).…”