Abstract:

An online pressurized extraction-ultrahigh-performance liquid chromatography-ion trap-time-of-flight mass spectrometry (online PLE-UHPLC-IT-TOF-MS) platform was configured for the rapid and direct profiling of the chemical constituents of Boschniakia rossica (B. rossica). Notably, only a sub-microgram amount (0.5 mg) of B. rossica was placed in an empty guard column core, which was then filled up with normal-phase silica gel as an extraction vessel. The guard column core was placed inside a guard column holder in the column oven (70℃) and connected to the UHPLC-IT-TOF-MS system via metal tubing. The extraction phase was maintained for 3 min with 0.1% (v/v) formic acid as the extraction solvent. The extraction and elution phases for the entire measurement were segmented by a 6-port/2-channel electronic valve. In the elution phase, 0.1% (v/v) aqueous formic acid-acetonitrile containing 0.1% (v/v) formic acid was the mobile phase, and the components of interest that accumulated at the front of the column were eluted into the IT-TOF-MS system for detection. A total of 48 compounds were observed, and according to the literature, database, and mass fragmentation pathways, 45 compounds, including 10 phenylethanol glycosides, 14 iridoid glycosides, and 21 phenylalanine glycosides, were identified from B. rossica. This study provides reliable information regarding the chemical composition and quality evaluation of B. rossica. Moreover, it offers a promising analytical pipeline for the chemical composition characterization of traditional Chinese medicines.

Key words: online pressurized liquid extraction, Boschniakia rossica (B. rossica), chemome profiling, mass fragmentation pathways, phenylpropanoid glycosides