Ethanolamine glycerophospholipid structure

The simplest of the glycerophospholipids is phosphatidic acid, in which phosphate is linked to the third hydroxyl function, forming a phosphate ester. More complex glycerophospholipids are derivatives of phosphatidic acid in which one of several groups is attached commonly choline, ethanolamine, serine, or myo-inositol. Structures are collected in table 19.1. 

Cephalins are glycerophospholipids present in foods. They differ from lecithins by having ethanolamine or serine instead of choline in their structure. Could you differentiate between lecithins and cephalins on the basis of the three tests to be performed in this experiment ... 

Lyso-glycerophospholipids Another widely distributed class of lipids, which occurs only in small amounts, is comprised of the lyso-phosphatidyl cholines and lyso-phosphatidyl ethanolamines. These compounds are formed in normal tissue by the action of phospholipase A on phosphatidyl choline and phosphatidyl ethanolamine. The enzyme attacks the fatty acid ester bond in the /3-position, splitting off a monoenoic or polyenoic fatty acid (Tattrie 1959 Hanahan 1960). The naturally occurring a -acyl residues are predominantly saturated. The structures of lysophosphatidyl choline and lysophosphatidyl ethanolamine are given in the following figures ... 

Lecithins and cephalins are two types of glycerophospholipids that are particularly abundant in brain and nerve tissues as well as in egg yolks, wheat germ, and yeast. Lecithins contain choline, and cephalins usually contain ethanolamine and sometimes serine. In the following structural formulas, the fatty acid that is used as an example is palmitic acid ... 

---