| The total lipid was extracted from Nannochlopsis sp.by mixed n-hexane and ethanol solvent, neutral lipid, glycolipid and phospholipid were obtained after lipid fractionation, the components in the three lipids were separated by thin-layer chromatography, and quantitatively determined with gas chromatography, and the fatty acid compositions of the components in neutral lipid, glycolipid and phospholipid were also determined. At the same time, the distribution of EPA in each lipid was analyzed.The results showed that the proportions of neutral lipids, glycolipids and phospholipids in glycerides of total lipid of Nannochlopsis sp. were 33.42%, 38.22% and 28.36%, respectively. The main components of neutral lipids were triacylglycerol (TAG) and free fatty acid with the contents of 927 g/100 g and 5.79 g/100 g respectively in the total lipid; the main components of glycolipids were medium monogalactose diglyceride(MGDG) and digalactosyl diglyceride (DGDG) with the contents of 14.03 g/100 g and 5.81 g/100 g, respectively in the total lipid; the main components of phospholipids were phosphatidylethanolamine (PE), phosphatidycholine (PC) and phosphatidylinositol (PI)with the contents of 622, 3.53 g/100 g and 1.53 g/100 g, respectively in the total lipid. The absolute total content of the three lipids in total lipid was 51.49 g/100 g. The fatty acid composition of different lipids was quite different. EPA had a higher proportion in monoglyceride (MAG), MGDG, DGDG and PE, accounting for 16.94%, 37.24%,14.32% and 10.51% of the total fatty acids of each component, respectively. EPA had the lowest distribution in neutral lipids, and 83.59% of EPA existed in the form of glycolipids. |
