2.6. Fractionation of total lipids
The total lipid extract was separated into non-polar
and polar lipid extracts by using Sep-Pak silica cartridges
(Water Corporation, Milford, Massachusettes,
USA) as described by Juaneda and Roquelin (1985).
The samples (50–70 mg of total lipid extract) were
loaded on the top of the cartridges. Non-polar lipids
were eluted with 50 ml of chloroform. Thereafter, the
polar lipid fraction containing the phospholipids was
eluted with 30 ml of methanol. The lipid composition
of both fractions was analyzed by TLC–FID.