Trace 1310 tsq 9000

The volatile components were separated, collected, and analyzed using a triple quadrupole GC-MS (Trace 1310/TSQ 9000, Thermo Scientific) (23 (link)). The headspace vial was filled with nitrogen to expel the air in the vial, and 5 mL tested sample was taken into the Thermo RSH autosampler for extraction. The extraction head was placed in the gas chromatography injection port, the injection port temperature was 250°C, the aging was 30 min, the oven temperature was set to 80°C, the water bath was set for 20 min, the adsorption extraction was 30 min, and the extraction head was inserted into the injection port for analysis for 5 min. The MPN content was determined reference to the method described by Yoshimura using the Agilent 1260 fluorescence detector (detection wavelength was 291 nm) (24 (link)).

Leaves of S. tenuifolia at flowering stage were collected, and 7 g fresh leaves were accurately weighed and placed in a round-bottom flask with 100 mL deionized water for distillation. Camphor was used as the internal standard (final concentration at 15 ng·μL⁻¹), and n-hexane as the carrier solvent [33 (link)].
Detection was performed using a triple quadrupole gas chromatography-mass spectrometer (Trace1310/TSQ 9000, Thermo Scientific). Analytical conditions: TG-5 ms column (0. 25 mm × 30 m, 0. 25 μm); programmed ramp-up: from 50 °C, hold for 5 min, ramp-up to 90 °C at 10 °C·min⁻¹, hold for 10 min, ramp-up to 160 °C at 10 °C·min⁻¹, hold for 10 min, ramp-up to 250 °C at 10 °C·min⁻¹, hold for 10 min. The carrier gas was helium at a flow rate of 1.00 mL·min⁻¹, a splitting ratio of 40:1, and an injection volume of 1.0 μL. MS conditions: EI ion source, ion source temperature 230 °C, interface temperature 250 °C, electron energy 70 eV, scanning range 30–1000 m·z⁻¹. Components were identified according to the NIST17 mass spectrometry standard database.