1987 Volume 35 Issue 2 Pages 705-710
A bacterial strain capable of hydrolyzing glycyrrhizin (GL) to glycyrrhetic acid (GA) was isolated from human feces. This bacterium was identified as Eubacterium sp. The GL-hydrolyzing activity increased in parallel with the growth of this bacterium, which also produced β-D-glucuronidase (EC 18.104.22.168) acting on β-D-glucuronides of phenolic compounds such as phenolphthalein mono-β-D-glucuronide. GL-hydrolyzing activity was recovered in the supernatant fraction after disruption of this bacterium with a French press and was partially purified by means of ammonium sulfate fractionation, and Sephadex G-200 and octyl-Sepharose column chromatographies.
GL-hydrolyzing enzyme was separated from the β-D-glucuronidase which hydrolyzes β-D-glucuronides of phenolic compounds by octyl-Sepharose column chromatography, indicating that the GL-hydrolyzing enzyme is a novel type of β-D-glucuronidase.