Divinylbenzene carboxen polydimethylsiloxane dvb car pdms 50 30 μm

The volatile compounds were extracted via the HS-SPME technique. Three biological replicates derived from an individual plant were conducted. One gram sample was accurately placed in a 20 mL vial. Subsequently, internal standard of 1 μL 3-nonanone (0.04 μg/μL, chromatographic ethanol as solvent) was added into the vial. The vial was then sealed immediately and equilibrated for 2 min in the 70℃ water bath. A SPME fiber with Divinylbenzene/Carboxen/Polydimethylsiloxane (DVB/CAR/PDMS)-50/30 μm purchased from Supelco was used for extraction. The extraction was carried out at 70℃ for 35 min.

Chloroform (CHCl₃), n-hexane, methanol (MeOH) and acetonitrile were supplied by Merck (Darmstadt, Germany). Normal alkanes standards (C7–C30), methoxyamine hydrochloride, N-methyl-N-(trimethylsilyl) trifluoroacetamide (MSTFA), pyridine, formic acid, isoamyl alcohol, ribitol, gallic acid, potassium persulfate, hydrochloric acid (HCl), methanoic acid, ferric chloride (FeCl₃), 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2′-azino-bis-3-ethylbenzothiazoline-cis-sulfonic acid (ABTS), 6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid (Trolox), 2,4,6-tripyridyl-s-triazine (TPTZ), Folin–Ciocalteu's phenol, acetic acid, and standards of phenolic compounds were obtained from Sigma-Aldrich (St. Louis, Missouri, USA). Solid phase microextraction (SPME) fiber coated with divinylbenzene/carboxen/polydimethylsiloxane (DVB/CAR/PDMS, 50/30 μm) was purchased from Supelco (Oakville, ON, Canada).