title: Bioactive microbial metabolites from glycyrrhetinic acid.
abstract: Biotransformation of 18beta-glycyrrhetinic acid, using Absidia pseudocylinderospora ATCC 24169, Gliocladium viride ATCC 10097 and Cunninghamella echinulata ATCC 8688a afforded seven metabolites, which were identified by different spectroscopic techniques (1H, 13C NMR, DEPT, 1H-1H COSY, HMBC and HMQC). Three of these metabolites, viz. 15alpha-hydroxy-18alpha-glycyrrhetinic acid, 13beta-hydroxy-7alpha,27-oxy-12-dihydro-18beta-glycyrrhetinic acid and 1alpha-hydroxy-18beta-glycyrrhetinic acid are new. The 13C NMR data and full assignment for the known metabolite 7beta, 15alpha-dihydroxy-18beta-glycyrrhetinic acid are described here for the first time. The major metabolites were evaluated for their hepatoprotective activity using different in vitro and in vivo models. These included protection against FeCl3/ascorbic acid-induced lipid peroxidation of normal mice liver homogenate, induction of nitric oxide (NO) production in rat macrophages and in vivo hepatoprotection against CCl4-induced hepatotoxicity in albino mice.
authors.affiliation: Department of Pharmacognosy, Faculty of Pharmacy, Mansoura University, Mansoura 35516, Egypt.
authors.forename: Galal T
authors.initials: GT
authors.lastname: Maatooq
authors.forename: Amani M
authors.initials: AM
authors.lastname: Marzouk
authors.forename: Alexander I
authors.initials: AI
authors.lastname: Gray
authors.forename: John P
authors.initials: JP
authors.lastname: Rosazza
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000378:metabolism / Q000494:pharmacology* / Q000627:therapeutic use; D001205:Ascorbic Acid; D001711:Biotransformation; D002251:Carbon Tetrachloride; D056486:Chemical and Drug Induced Liver Injury / Q000517:prevention & control*; D005658:Fungi / Q000378:metabolism; D006034:Glycyrrhetinic Acid / Q000378:metabolism* / Q000494:pharmacology; D015227:Lipid Peroxidation / Q000187:drug effects*; D008099:Liver / Q000187:drug effects*; D008264:Macrophages / Q000187:drug effects; D051379:Mice; D009569:Nitric Oxide / Q000096:biosynthesis; D008517:Phytotherapy; D010936:Plant Extracts / Q000378:metabolism / Q000494:pharmacology* / Q000627:therapeutic use; D020011:Protective Agents / Q000378:metabolism / Q000494:pharmacology / Q000627:therapeutic use; D051381:Rats
chemical_list: D000975:Antioxidants; D010936:Plant Extracts; D020011:Protective Agents; D009569:Nitric Oxide; D002251:Carbon Tetrachloride; D006034:Glycyrrhetinic Acid; D001205:Ascorbic Acid