Isolation and identification of metabolites from dihydromyricetin.
Dihydromyricetin (DHM) is the major bioactive constituent of Rattan Tea, which is the tender stems and leaves of Ampelopsis grossendentata. Seven metabolites (2-8) of DHM (1) were obtained by the chromatographic method. The metabolites 2-5 were obtained from the urine of rats administered orally with DHM; and metabolites 6-8 were detected in the fecal specimens of rats, which were also produced by human intestinal bacteria (HIB) in vitro, and were separated from the cultured media of HIB containing DHM. Their structures were elucidated as 5,7,3',5'-tetrahydroxyflavanonol (2); 5,7,3',5'-tetrahydroxy-4'-methoxyflavanonol (3); 5,7,4',5'-tetrahydroxy-3'-methoxyflavanonol (4); and dihydromyricetin-O-5-beta-D-glucuronide (5); (2R,3S)-5,7,3',4',5'-pentahydroxyflavanonol (6); 3,4,5,7,3',4',5'-hepthydroxyflavan (7) and 5,7,3',4',5'-pentahydroxyflavanone (8) on the basis of UV, NMR and LC-MS/MS data. These seven metabolites were formed through familiar metabolic reactions. Dihydromyricetin-O-5-beta-D-glucuronide (5) is a new compound. The (13)C-NMR data of (2) and (4) are reported for the first time.
Zhang
Yansong
Y
Department of Natural Medicines and State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University Health Science Center, No. 38 Xueyuan Road, Beijing 100083, P. R. China.
Que
Sheng
S
Yang
Xiuwei
X
Wang
Bin
B
Qiao
Liang
L
Zhao
Yuying
Y
D000818:Animals; D002851:Chromatography, High Pressure Liquid; D044948:Flavonols / Q000032:analysis / Q000378:metabolism*; D020719:Glucuronides / Q000032:analysis / Q000378:metabolism; D008297:Male; D013058:Mass Spectrometry; D019906:Nuclear Magnetic Resonance, Biomolecular / Q000379:methods; D051381:Rats; D017207:Rats, Sprague-Dawley; D013056:Spectrophotometry, Ultraviolet
D044948:Flavonols; D020719:Glucuronides; C472036:dihydromyricetin