Abstract
By human intestinal bacteria, glycyrrhizin (18β-glycyrrhetinic acid-3-O-[β-D-glucuronopyranosyl-(1→2)-β-D-glucuronopyranoside], GL) was metabolized to 18β-glycyrrhetinic acid (GA) : the main pathway metabolized GL to GA by glucuronidases of Bacteroides J-37 and Eubacterium sp. GLH and the minor pathway metabolized GL to 18β-glycyrrhetinic acid-3-O-β-D-glucuronide (GAMG) by β-glucuronidase of Streptococcus LJ-22. β-Glucuronidase from Streptococcus LJ-22 hydrolyzed GL to GAMG (not GA). The molecular weight and optimal pH of the enzyme were 240 kDa and 5-6.
