2.4.3. Lipid extraction
The extraction of total cellular lipid was performed according to Bligh and Dyer (Bligh and Dyer, 1959) with modifications (Bourque and Titorenko, 2009). Lipid was extracted from lyophilized bio-mass using a mixture of chloroform and methanol (2:1 v/v). The mixture was centrifuged to partition the lipids into the solvent, then the solvent was evaporated using a Nitrogen Evaporation Sys-tem (Organomation Associates Inc., USA). Lipid content was repre-
sented as a percentage of dry cell weight (%, W/W). Lipid concentration was defined as the amount of extracted cellular lipid in per liter working volume (g/L).