Development of a headspace solid-phase microextraction gas chromatography-mass spectrometry method to study volatile organic compounds (VOCs) emitted by lavender roots

: A headspace solid-phase microextraction (HS-SPME) method combined with gas chromatography-mass spectrometry (GC/MS) was developed and optimized for the extraction and the analysis of volatile organic compounds (VOCs) from lavandin and fine lavender roots. Optimal parameters to extract volatile molecules from ground and intact roots were determined using a divinylbenzene-carboxen-polydimethylsiloxane (DVB/CAR/PDMS) coating fiber at 70 °C for 60 min. A total of 99 VOCs, including 40 monoterpenoids, 15 sesquiterpenoids, 1 diterpenoid and 2 coumarins were detected. The main compounds detected in lavandin roots were fenchol, borneol, and coumarin. Performances of the optimized SPME GC/MS method were evaluated via the comparison of VOC emissions between roots from different cultivars of fine lavender (7713 and maillette) and lavandin (abrial and grosso). Chemometric analysis, using partial least squares-discriminant analysis (PLS-DA), suggests fifteen significant features as potential discriminatory compounds. Among them, β-phellandrene allows discrimination between lavender and lavandin varieties.