Effects of glycyrrhizin and glycyrrhetic acid on the growth, glycyrrhizin beta-D-glucuronidase and 3 beta-hydroxysteroid dehydrogenase of human intestinal bacteria.
The peak of glycyrrhizin (GL) beta-D-glucuronidase activity for Ruminococcus sp. PO1-3 and Eubacterium sp. GLH changed to 24 h from 12 h of culture and to 12 h from 48 h, respectively, at almost the same level by the addition of 1.0 mM GL. This enzyme activity was about 20-fold higher in Eubacterium sp. GLH than in Ruminococcus sp. PO1-3. GL beta-D-glucuronidase activity of Ruminococcus sp. PO1-3 with Eubacterium sp. GLH and the intestinal flora showed a maximal peak at 12 h of culture in the presence and absence of 1.0 mM GL. This enzyme activity was about 2.5-fold higher in mixed bacteria than in intestinal flora. 3Beta-hydrosteroid dehydrogenase activity of Ruminococcus sp. PO1-3 and Ruminococcus sp. PO1-3 with Eubacterium sp. GLH was suppressed greater in the presence of GL than without GL. Also, Ruminococcus sp. PO1-3, Eubacterium sp. GLH, and a mixture of both and intestinal flora, metabolized 1.0 mM GL to glycyrrhetic acid (GA) in yields of about 10, 70, 40 and 100%, respectively, with 24 h culture. From the level of GL beta-D-glucuronidase activity, it is considered that the metabolism of GL by intestinal flora is due to both enzymatic and non-enzymatic reactions. Moreover, GA at a concentration of 1.0 mM suppressed growth of Ruminococcus sp. PO1-3, Eubacterium sp. GLH, and the mixture of both and intestinal flora, which metabolized 1.0 mM GA to a negligible amount of 3-oxo-glycyrrhetic acid, indicating the accumulation of unchanged GA. GL beta-D-glucuronidase activity of intestinal flora was enhanced by GA, which stimulated bacteria possessing particular this characteristic.
Akao
T
T
Faculty of Pharmaceutical Sciences, Toyama Medical and Pharmaceutical University, Sugitani, Japan.
D015096:3-Hydroxysteroid Dehydrogenases / Q000378:metabolism*; D001421:Bacteria, Anaerobic / Q000187:drug effects* / Q000201:enzymology / Q000254:growth & development; D005051:Eubacterium / Q000187:drug effects* / Q000201:enzymology / Q000254:growth & development; D005243:Feces / Q000382:microbiology; D005966:Glucuronidase / Q000378:metabolism*; D006034:Glycyrrhetinic Acid / Q000378:metabolism / Q000494:pharmacology*; D019695:Glycyrrhizic Acid / Q000378:metabolism / Q000494:pharmacology*; D006801:Humans; D007422:Intestines / Q000382:microbiology*
D019695:Glycyrrhizic Acid; D015096:3-Hydroxysteroid Dehydrogenases; C052783:glycyrrhizin beta-D-glucuronidase; D005966:Glucuronidase; D006034:Glycyrrhetinic Acid