Characterization of polyphenol compounds from the roots and stems of Parthenocissus laetevirens by high-performance liquid chromatography/tandem mass spectrometry.

A facile method based on high-performance liquid chromatography coupled with electrospray ionization tandem mass spectrometry (HPLC/(-)ESI-MSn) has been established for the analyses of polyphenol compounds in the root and stems of Parthenocissus laetevirens. Two characteristic fragments [C3O2 (68 Da) and C2H2O (42 Da)] were utilized for the structural identification of polyphenols. Based on the reference standards, the fragment C3O2 was presented when the compound possessed a 2,3-dihydro-1H-indene-4, 6-diol moiety. Meanwhile, the C2H2O fragment (42 Da) yielded from the resorcinol ring was confirmed by resveratrol and three synthesized compounds identified as (E)-5-styrylbenzene-1,3-diol, (E)-4-styrylphenol and (E)-4-(3,4,5-trimethoxystyryl)phenol. FTICR-MSn was performed to further confirm the structures of the fragments. Overall, 15 polyphenol compounds were characterized. Three polyphenol compounds were initially and tentatively characterized from P. laetevirens for the first time, and one was proposed as a novel compound. Furthermore, a pair of stereoisomers was readily distinguished by breakdown curves, and the trans-, cis-isomers could be identified by HPLC/DAD-UV spectra.