2.5 Quantification of total fatty acid methyl esters (FAMEs)
A modified Bligh-dyer technique was adapted from shaikh et al[35] for extracting total fatty acid methyl esters (FAMEs). The hexane layer was injected into an Agilent 6890 gas chromatograph (GC) instrument, which was connected to a triple quadrupole outfitted with an OMEGAWAX 250 column (30 m x 0.25 m x 0.25 m). The GC-MS running conditions were as stated by Kareya et al [47]. Concisely, 2 L of the sample was run in the split mode (1:10) for 25 minutes, with the beginning oven temperature set at 150 °C and a simultaneous escalation of 10 °C min-1 to 240 °C. For quenching, helium (He) and nitrogen (N2) gas were employed at flow rates of 2.25 mL min-1 and 1.5 mL min-1, respectively. The data was collected using the Agilent 7000D triple quadrupole selective mass detector, which has a scan range of 30 to 550 amu. The produced peaks were compared to NIST libraries for identification and alignment based on retention indices as well as mass spectral similarity (cut-off hits with R-values greater than 600 were selected).