PT  - JOURNAL ARTICLE
AU  - Chunru Cheng
AU  - Min Yang
AU  - Kate Yu
AU  - Shuhong Guan
AU  - Sijia Tao
AU  - Alan Millar
AU  - Xiaoyan Pang
AU  - Dean Guo
TI  - Identification of Metabolites of Ganoderic Acid D by Ultra-Performance Liquid Chromatography/Quadrupole Time-of-Flight Mass Spectrometry
AID  - 10.1124/dmd.112.047506
DP  - 2012 Dec 01
TA  - Drug Metabolism and Disposition
PG  - 2307--2314
VI  - 40
IP  - 12
4099  - http://dmd.aspetjournals.org/content/40/12/2307.short
4100  - http://dmd.aspetjournals.org/content/40/12/2307.full
SO  - Drug Metab Dispos2012 Dec 01; 40
AB  - Ganoderic acid D (GD) is the major active triterpenoid in Ganoderma lucidum, a medicinal fungus used daily. However, the metabolic fate of GD remains unknown. To know whether GD is extensively metabolized, we first investigated the metabolism of GD in vitro and in vivo. The metabolic profiles of the bile samples obtained from rats in vivo were almost the same as those obtained in vitro. Using ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometry, a total of 25 metabolites were identified from the bile sample. Few metabolites were found in the urine samples. These results indicated that biliary rather than renal clearance was the major route of excretion. The major metabolites were identified by comparison with the standard reference compounds. Metabolites at low concentrations were identified by interpreting the mass spectra. Both phase I and phase II metabolites were observed. The metabolic transformation included reduction, monohydroxylation, dihydroxylation, trihydroxylation, oxidation, desaturation, sulfation, and glucuronidation. The main metabolic soft spots in the chemical structure of GD were the 3-carbonyl group, angular methyl groups, the 7-hydroxy group, and the 26-carboxylic acid moiety. Overall, this study gives us an insight into the metabolism of GD, an active oxygenated tetracyclic triterpenoid.