Identification of major constituents from propolis by LC-IT-TOF-MS

A qualitative analytical method of liquid chromatography coupled with ion trap time-of-flight mass spectrometry (LC-IT-TOF/MS) was developed for identification of major constituents in propolis from China (Shandong). The LC-IT-TOF-MS was performed on a Shim-pack VP-ODS column (2. 0 mm × 150 mm, 5μm) with the mobile phase consisting of acetonitrile and water containing 0. 2% formic acid in gradient mode, and the flow rate was set at 0. 3 mL/min. Negative ion mode was used for IT-TOF-MS. According to the accurate molecular weight, MS fragment pathway, comparison with the retention time of reference compounds, total 31 compounds, including twenty-five phenolic acids and six flavonoids were identified. The LC-IT-TOF-MS qualitative analysis method can be used for analyzing major components of propolis quickly and accurately.