Phosphatidic acid Phosphatidyl choline, 861,

The following phosphoglycerides are derived from phosphatidic acid. Phosphatidyl choline or lecithin (phosphate group esterified with the... 

Phosphatidic acid Phosphatidyl ethanolamine Phosphatidyl serine Phosphatidyl choline Phosphatidyl inositol Sphingomyelin. 

Complete hydrolysis of phosphatidyl choline yields phosphoric acid, glycerol, saturated and unsaturated fatty acids. Phosphatidyl choline and phosphatidyl ethanolamine are obtained by routes similar to the above (11.102). In eukaryotic cells, various phospholipids are biosynthesised from phosphatidic acid via cytidine diphosphate diacylglycerol (11.103). 

The fatty acids containing phospholipids have been postulated to be chemically bonded to the rubber molecule at the a-terminal end and are the branching point of the rubber. Hydrolysis of phospholipids produces phosphate, which could increase the stability of ammoniated latex during storage. Of phosphatidyl choline, phosphatidyl ethanolamine and phosphatidic acid, phosphatidyl ethanolamine has been found to be the most effective antioxidant. ... 

Phosphatidyl choline, phosphatidic acid, phosphatidyl inositol, and phosphatidyl ethanolamine in soy lecithin Zorbax Sil, 4.6 x 150 mm, 45 C 78.4 21.6 02/(95 4.95 0.05 MeOH/H20/triethylamine) Evaporative light scattering 32... 

Phosphatidyl choline (two compounds), phosphatidic acid, phosphatidyl glycerol, and PEG adduct of phosphatidyl ethanolamine demonstration of subcritical fluid chromatography Phenomenex Luna Octyl, 4.6 X 250 mm, 7(FC Gradient A = CO2 B = 50 50 EtOH/MeOH containing 0.1% tri-fluoroacetic acid 9% B to 15% B in 14 min, then to 40% in 0.1 min Evaporative light scattering 33... 

Analogues of phosphatidyl ethanolamine, phosphatidyl choline, and phosphatidic acid with pantoic acid skeleton were prepared by phosphorylation with the respective phosphoric mono-, bis-, and tristriazolide [17]... 

The nomenclature for associating individual fatty acid groups with particular phosphodig-lyceride derivatives is straightforward. For instance, a phosphatidic acid (PA) derivative which contains two myristic acid chains is commonly called dimyristoyl phosphatidic acid (DMPA). Likewise, a PC derivative containing two palmitate chains is called dipalmitoyl phosphatidyl choline (DPPC). Other phosphodiglyceride derivatives are similarly named. 

It is a complex mixture of acetone-insoluble phosphatides that consists chiefly of phosphatidyl choline, phosphatidyl ethanolamine, and phosphatidyl inositol combined with various amounts of other substances such as triglycerides, fatty acids, and carbohydrates. Refined grades of Lecithin may contain any of these components in varying proportions and combinations depending on the type of fractionation used. In its oil-free form, the preponderance of triglycerides and fatty acids is removed and the product contains 90% or more of phosphatides representing ah or certain fractions of the total phosphatide complex. Edible diluents, such as cocoa butter and vegetable oils, often replace soybean oil to improve functional and flavor characteristics. Lecithin is only partially soluble in water, but it readily hydrates to form emulsions. The oil-free phosphatides are soluble in fatty acids, but they are practically insoluble in fixed oils. When ah phosphatide fractions are present, Lecithin is partially soluble in alcohol and practically insoluble in acetone. 

Phosphatidyl choline (lecithin), phosphatidyl serine, phosphatidyl glycerol, phosphatidyl inositol, phosphatidic acid. 

Fig. 6.15 Formation and function of diacylglycerol. The figure schematically shows two main pathways for formation of diacylglycerol (DAG). DAG can be formed from PtdlnsP2 by the action of phospholipase C (PL-C). Another pathway starts from phosphatidyl choline. Phospholipase D (PL-D) converts phosphatidyl choline to phosphatidic acid (Ptd), and the action of phosphatases results in DAG. Arachidonic acid, the starting point of biosynthesis of prostaglandins and other intracellular and extracellular messenger substances, can be cleaved from DAG. PKC protein kinase C Ptdlns phosphatidyl inositol.

After ethanolamine or choline has entered a cell, it is phosphorylated and converted to a CDP derivative. Then phosphatidylethanolamine or phosphatidylcholine is formed when diacylglycerol reacts with the CDP derivative. Triacylglycerol is produced if diacylglycerol reacts with acyl-CoA. CDP-Diacylglycerol, formed from phosphatidic acid and CTP, is a precursor of several phospholipids, for example, phosphatidyl-glycerol and phosphatidylinositol. 

Phosphatidylcholine (PC) can be synthesized in eukaryotes starting from choline (Figure 19.5) or from phosphatidic acid via CDP-diacylglycerol, phosphatidyl serine (PS) and phosphatidylethanolamine (PE). The interconversion of PS, PE, and PC is shown here. 

Phospholipids, or phosphoglycerides, are amphipathic compounds that are used to make cell membranes, generate second messengers, and store fatty acids for use in the generation of prostaglandins. They can be synthesized from phosphatidate, an intermediate in triglyceride synthesis. Two common phospholipids, phosphatidyl choline and phosphatidyl inositol, are shown below (4). 

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