Nineteen triterpenoids, including eleven ursane triterpenoids and eight olenane triterpenoids, were isolated from the stems of Uncaria macrophylla Wall. by comprehensive chromatographic methods. Structure elucidation of the compounds was succeeded by extensive spectroscopic analysis. Twelve compounds were obtained from this plant for the first time, among which six compounds were obtained from the genus Uncaria for the first time.
An ultra high performance liquid chromatography coupled with hybrid quadrupole-orbitrap mass spectrometry （UHPLC-quadrupole-orbitrap MS） method was developed to systematically analyze chemical constituents of Scutellaria barbata D. Don. The 70% methanol extract was separated on an Agilent Eclipse Plus Cl8 column （1.8μm, 150 mm×2.1 mm）, and eluted with a gradient of methanol-acetonitrile-water containing 0.1% formic acid at a flow rate of 0.25 mL/min. Constituents were identified by HRMS in the negative ion mode using both full scan and two-stage threshold-triggered mass modes. A total of 56 compounds, including 20 free flavonoids, 20 flavonoid O-glycosides, 2 flavonoid C-glycosides, 4 phenylethanoid glycosides, and 10 phenolic compounds were identified by analyzing their high resolution mass spectral data. Among them, 8 flavonoids and 2 phenylethanoid glycosides were unambiguously identified by comparing with reference standards. This study demonstrates that hybrid quadrupole-orbitrap mass spectrometry is a powerful tool in structural identification of unknown compounds in comolicated herbal extracts.
The root of Hedysarum multijugum（RHM） is recorded as a folk herbal medicine in China and is sometimes used as a substitute for Hedysari Radix, which is a famous traditional Chinese medicine derived from the roots of Hedysarum polybotrys. In the present study, a sensible, reliable, and reproducible HPLC-DAD fingerprint analysis method for RHM was developed and then subsequently applied to analyze RHM samples from different origins. The chemical constituents of the RHM samples were generally consistent, although it was slightly affected by the local environment of the plant. In addition, the chemical constituency of RHM was shown to be significantly different from that of Hedysari Radix, suggesting that RHM is not suitable as a substitute for Hedysari Radix, at least from the chemical point of view.
