The essential oil of Pistacia vera L. at various temperatures of direct thermal desorption using comprehensive gas chromatography coupled with time-of-flight mass spectrometry

Abstract

The essential oil obtained from the hulls of Pistacia vera fruits using direct thermal desorption was resolved using comprehensive gas chromatography (GCxGC) coupled with time-of-flight mass spectrametry (TOP-MS). A range of temperatures (100, 150, 200, 250°C) far thermal desorption were applied ta extract volatile organic compounds from around 10mg of raw sample. Although different species profiles were produced at each temperature (notably browning products above 200°C), ?-pinene and (Z)-?-terpineol were found to be the major components at all temperatures studied. The number af compounds observed increased with increasing temperature. A temperature of 150°C is recommended as optimum for the direct thermal desorption of volatiles from matrices such as fruit hulls. The GCxGC separation chromatographically resolved several hundred components which when coupled for detection with TOP-MS gave high probability identifications for around 100 compounds. The comprehensive separation also separated a number of components which remained unresolved on a single GC column, such as camphene with butyrolactone and dodecane with p-cymene.