Table 3 shows the fatty acid compositions of the total lipid and the
various lipid classes from the SBT-E1 cells compared with the fatty
acid composition of the total lipid from the culture medium. The culture
medium was rich in saturated fatty acids (especially 16:0 and 18:0) and
monounsaturated fatty acids (especially 18:1n−9) but poor in polyunsaturated
fatty acids (PUFAs) (including 18:2n−6 and 18:3n−3) and
LC-PUFAs (including 20:4n−6, 20:5n−3, 22:5n−3 and 22:6n−3).
This was as expected because foetal bovine serum (FBS) was the source
of the fatty acids in the culture medium (Scholefield and Schuller,
2014). The fatty acid composition of the total lipid from the SBT-E1
cells reflected that of the culture medium except that there was
evidence for enrichment of the cells with 20:4n−6, 22:5n−3 and
22:6n−3. The various fatty acids were distributed differently between
the different classes of lipids. Neutral lipids were rich in 16:0 whereas
PC was rich in 18:1n−9. PE was rich in the most abundant LC-PUFAs
20:4n−6, 22:5n−3 and 22:6n−3. PE also contained the majority
of the 20:5n−3 but the level was very low compared with other LCPUFAs.