Structure elucidation of metabolites of gambogic acid in vivo in rat bile by high-performance liquid chromatography-mass spectrometry and high-performance liquid chromatography-nuclear magnetic resonance.
Gambogic acid (GBA), the main component of Gamboge, possesses significant anti-tumour activity. Due to its structural complexity, little is known about GBA metabolism. Here, we investigate the metabolism of GBA in vivo in rat bile. Identification of the metabolites formed was elucidated using high-performance liquid chromatography (HPLC) with UV-vis detection, HPLC/ion trap electrospray ionization-mass spectrometry, as well as HPLC/nuclear magnetic resonance. Four main metabolites were determined. Two phase I metabolites, 10-hydroxygambogic acid and 9,10-epoxygambogic acid, were oxides on the 9,10-olefinic bond of GBA. The others phase II metabolites, were 9,10-epoxygambogic acid-30-O-glucuronide and 10-hydroxylgambogic acid-30-O-glucuronide.
Feng
Feng
F
Department of Phytochemistry, China Pharmaceutical University, Nanjing 210009, China.
Liu
Wenyuan
W
Wang
Yinghong
Y
Guo
Qinglong
Q
You
Qidong
Q
D000818:Animals; D001646:Bile / Q000378:metabolism*; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D015394:Molecular Structure; D051381:Rats; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*; D013056:Spectrophotometry, Ultraviolet; D044004:Xanthones / Q000737:chemistry* / Q000378:metabolism
C550001:10-hydroxygambogic acid; D044004:Xanthones; C052659:gambogic acid