, 2007a and Budziak et al., 2008). Before measurements the fibres were conditioned according to Supelco’s recommendations. The experiment for the selection of the fibre was performed with 0.1 mg of fresh chopped leaves inside 4 mL amber vials capped

with PTFE-coated septa, at temperature controlled of 30 °C and headspace extraction of 5 min. Desorption of the analytes was carried out at 240 °C during 60 s. Fig. 1 shows the results for the extraction efficiency evaluated by the peak areas in chromatograms obtained with the three studied fibres. The NiTi-ZrO2-PDMS (35 μm) MAPK inhibitor fibre has a higher adsorptive capacity compared to the other fibres evaluated. It proved sensitivity and precision, with coefficient of variation (CV%) smaller than 10%, and was chosen for the study of the chemical composition of the selleck chemicals llc essential oil of leaves and fruits of M. indica var. coquinho. Using the NiTi-ZrO2-PDMS fibre the following parameters that could affect the extraction efficiency were optimised: mass of sample, extraction time and temperature and desorption time. Fruit’s experiments were performed with masses of 10 and 100 mg of sample and leaves’ experiments were performed with 1, 10, 50 and 100 mg of sample. The effect of the temperature on the extraction process was evaluated by testing successive conditions at room temperature (30 °C), 40, 50 and 60 °C. The influence of the exposure time of the fibre was

studied in experiments performed at 15, 30, 45, and 60 min. The time required for desorption of the substances from the fibre coating was determined testing the times of 30, 60, 90 and 120 s at Mephenoxalone an injector temperature of 250 °C. For each experiment, at least three replicates of extraction were performed. The HS-SPME/GC-MS analyses were performed with Varian GC–MS system comprising a CP-3900 gas chromatograph (Walnut Creek, CA, USA) with 1177 injector and ion-trap mass spectrometer (Saturn 2100-T/MS/MS). Chromatographic separation was performed on a Factor

Four VF-5 ms fused-silica capillary column (30 m × 0.25 mm, df 0.25 μm), from Varian (Walnut Creek, CA, USA). A SPME liner (72 mm × 0.75 mm i.d) purchased from Varian was used. The initial temperature of oven was of 50 °C (2 min) and increased to 250 °C at 3 °Cmin−1, and the injector was kept at 250 °C. Helium (99.999% purity) was used as carrier gas at a constant flow of 1.0 mL min−1. The temperatures of the manifold, GC–MS interface and the ion trap were 50, 250 and 200 °C, respectively. The MS scan parameters included electron impact ionisation voltage of 70 eV, mass range of 40–450 m/z and scan interval of 0.5 s. Saturn GC/MS 5.52 workstation software was used for instrument control and data treatment. The HS-SPME/GC-MS analyses were made in the splitless mode, 60 s closed valve, 15 min more with the split valve open (ratio 1:50) to clean the fibre, followed by a split ratio of 1:20 to the analysis end.