The fatty acid methyl esters (FAMEs) profile of the microalgae lipids was used as a proxy for the fatty acid profile. FAMEs were prepared via the direct methylation of fatty acids in the presence of an HCl catalyst according to the procedure given by Lewis et al. [16]. Dry algal biomass was reacted directly with a mixture of methanol, chloroform and HCl (10:1:1 v/v/v) in 10 mL crimped vials at 90 C for 2 h. FAMEs were then extracted using hexane/chloroform (4:1, v/v) and analyzed via
gas chromatography using an ion trap (GC-QP2010, Shimadzu, Japan). Fatty acid profiles of the microalgae strains were deduced by comparison with a 37 FAME mix standard (i.e. Supelco 37 FAME mix, C4-C24). Each sample was spiked with n-heptadecanoic acid (C17:0) to a final concentration of 1 ppm as an internal standard. The capillary column of the GC/MS was a DB-5MS, of 30 m length, a film thickness of 0.25 mm and an internal diameter of 0.25 mm. Helium was used as the carrier gas. The oven temperature and injection temperature were set at 50 C and 280 C respectively. The temperature program of the GC was held at 50C for 2min and then increased to 150 C at a rate of 10 C min1, then to 185 C for 2 min and finally to 300 C for 2 min.