Qexactive orbitrap lc ms system

The chemical composition of PWE was analyzed on a Thermo Scientific Q Exactive Orbitrap LC/MS System. The water phase after being dried by using a lyophilizer was dissolved in methanol (100 ug/mL) and analyzed on a Shimadzu Shim-pack GIST C18 column (2.1 mm × 100 mm, 3 μm, Shimadzu, Kyoto, Japan). Ultrapure water (solvent A) and acetonitrile (solvent B) were used as mobile phases, and the mobile phase was added 0.1% formic acid (v/v). The gradient was as follows: 0–3 min, 10% B; 3–20 min, 10–40% B; 20–25 min, 40–60% B; 25.01–30 min, 100% B. The flow rate of mobile phases was 0.2 mL/min, the sample volume was 2.0 µL, and the temperature of the column oven was maintained at 35 °C. Data were collected in a negative ion mode. The mass range of the scan was m/z 50 to 1000. Other parameters for mass spectrometry were as follows: auxiliary gas flow, 8.0 L/min; sheath gas flow rate, 32.0 L/min; sweep gas, 4.0 L/min; spray voltage, 3.3 kV; S-lens RF level, 50%; resolution, 70,000; heater temperature, 350 °C; and capillary temperature, 320 °C. The total ion chromatogram, mass data, and MS/MS fragment ion data were analyzed by Xcalibur software. The identification of each compound in the PWE was compared with the reported data in the literature or the Metabolomics Innovation Center database.