2.7. GC–MS Analysis of FAMEs

GC–MS analyses were carried out on a GCMS-QP2010 (Shimadzu, Duisburg, Germany) equipped with a split/splitless injector and an AOC-20i autosampler. The chromatographic column was a SLB-Il60i (30 m × 0.25 mm id, 0.20 μm film thickness) column (Merck Life Science). The temperature program was as follows: 50 °C to 280 °C at 3.0 °C/min. Injector was kept at 280 °C; injection volume was 0.2 µL with a split ratio of 1:20. Helium was used as a carrier gas at 30 cm/s linear velocity and an initial inlet pressure of 31.7 KPa (50 °C). MS parameters were as follows: mass range 40–550 amu, with an event time of 0.20 s; ion source temperature 200 °C, interface temperature 220 °C; ionization mode EI (70 eV), detector voltage 0.98 kV. The GCMS solution software (Shimadzu) was used for data collection and handling. The C4–C24 FAMEs standard solution was used for linear retention indices (LRIs) calculation to support identification of analytes. Moreover, peaks assignment was carried out on the basis of a double filter, namely, the MS similarity spectra (over 80%) and a LRIs ±10 range compared to the value reported in the commercial database used (LIPIDS Mass Spectral Library (Shimadzu)).