*2.2. Gas Chromatograph–Mass Spectrometry (GC-MS) Analysis*

A Gas Chromatograph (Shimadzu GC-17A, Shimadzu, Milan, Italy) with Flame Ionization Detector (GC-FID) equipped with a 15 m × 0.1 mm × 0.1 mm capillary column (Supelco SPBTM-5, Merk KGaA, Darmstadt, Germany) was used. The operating condition followed those previously published [20]: 60 ◦C for 1 min, 60–280 ◦C at 10 ◦C/min, and then 280 ◦C for 1 min; injector temperature, 250 ◦C; and detector temperature, 280 ◦C with helium as carrier gas (1 mL/min). GC-MS analyses were performed with the same column and operative conditions mentioned above. Mass spectrometer parameters were the same as those previously published [21]. Component identification was based on comparison of their retention indexes with those relative to a mix of C9–C22 *n*-alkanes, computer matching of spectral MS data, and fragmentation patterns with those in libraries [22,23], and co-injections with authentic samples (see Table 1).
