Identification of three sulfate-conjugated metabolites of berberine chloride in healthy volunteers' urine after oral administration.
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.
Keywords:
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.