Jun Pan, Chen Yu, Da-yuan Zhu
2002
Citations
2
Influential Citations
57
Citations
Quality indicators
Journal
Acta pharmacologica Sinica
Abstract
AIM To identify the structure of unknown metabolites of berberine (Ber) in human urine after oral administration. METHODS Urine samples were obtained from 5 volunteers after they orally took Ber chloride 0.9 g per day for three days. Metabolites in urine samples were isolated and purified by polyporous resin column chromatography. The individual metabolites were identified mainly using electrospray ionization mass spectroscopy (ESI-MS) and proton nuclear magnetic resonance (1H NMR) spectroscopy. RESULTS Three unknown metabolites (M1, M2, and M3) were isolated. They were susceptible to arylsufatase. ESI-MS measurements of M1, M2, and M3 produced quasimolecular ions [M+H]+, m/z 17.9, 404.0, and 402.0 respectively. Especially, each of them produced a characteristic protonated ion [M-80+H]+, which can be ascribed as quasimolecular ions lost a SO3 fragment. 1H NMR spectra of the metabolites were also obtained and each of 1H signals was assigned. CONCLUSION Structures of M1, M2, and M3 were firmly identified as jatrorrhizine-3-sulfate, demethyleneberberine-2-sulfate, and thalifendine-10-sulfate, and the major metabolite was M2.