Polyunsaturated lecithin

Jimenez, M.A., Scarino, M.L., Vignolini, F., and Mengheri, E. 1990. Evidence that polyunsaturated lecithin induces a reduction in plasma cholesterol level and favorable changes in lipoprotein composition in hypercholesterolemic rats. J. Nutr. 120, 659-667. 

Enhancement of matrix degradation Polyunsaturated lecithins Colchicine Adenosine Collagenase activity... 

Li, J., Kim, C., Leo, AM., Mak, K.M., Rojkind, M., Lieber, C.S. Polyunsaturated lecithin prevents acetaldehyde-mediated hepatic collagen accumulation by stimulating collagenase activity in cultured lipocytes. Hepatology 1992 15 373-381... 

Demel RA, Geuts van Kessel W8. M., Van Deenen LL. M. The properties of polyunsaturated lecithins in monolayers and liposomes and the interactions of these lecithins with cholesterol. Biochim Biophys Acta 1972 266 26-40. 

Several strategies to treat alcoholic liver disease have been evaluated. Prednisolone may improve survival in patients with hepatic encephalopathy. Nutrients such as S-adenosylmethionine and polyunsaturated lecithin have been found to have beneficial effects in nonhuman primates and are undergoing clinical trials. Other medications that have been tested include oxandrolone, propylthiouracil, and colchicine. At present, however, none of these drugs is approved for use in the United States for the treatment of alcoholic liver disease. The current... 

R. A. Demel, W. S. M. Geurts van Kessel, and L. L. M. van Deenen, The Properties of Polyunsaturated Lecithins in Monolayers and Liposomes and the Interaction of these Lecithins with Cholesterol, Biochim. Biophys. Acta 266, 26-40 (1972). 

Porter, N.A., Wolf, R.A., and Weenen, H. The free radical oxidation of polyunsaturated lecithins. Lipids 15,163-167 (1980). 

Food. Lecithin is a widely used nutritional supplement rich ia polyunsaturated fatty acids, phosphatidylcholine, phosphatidylethanolamine, phosphatidjhnositol, and organically combiaed phosphoms, with emulsifying and antioxidant properties (38). 

The use of a modified starch, corn starch sodium octenyl succinate derivative, for encapsulation of sea buckthorn kernel oil (containing polyunsaturated fatty acids, tocopherols, tocotrienols, plant sterols and carotenoids) by spray-drying was found to improve oil stability. Better protection was afforded when the starch encapsulant was stored in its glassy state (Partanen et al. 2002). Methylcellulose and hydroxymethy-oellulose in combination with soy lecithin enabled the production of 40% (W/W) fish oil powders with improved stability (Kolanowski et al. 2004). 

Soybean oil contains 1.5-3.0% phospholipids (71). Crude soybean lecithin has an oil content of about 30%. PC is present at a level of about 16%., PE about 14%, and inositol phospholipids about 12% (7). As can be seen in Table 18 (8), the fatty acid compositions of soybean phospholipids are rich in polyunsaturated fatty acids. Miscellaneous low-level constituents include water, phosphatidic acid, pigments, galactosyl glycerides, various glycolipids, phosphatidylserine, carbohydrates, sterols, and tocopherols. Phosphorus content of crude soybean oil extracted from flours can vary depending on extraction temperature and flour moisture (72). 

Transesterification. Transesterification allows for the incorporation of free fatty acids into lecithin molecules. Unhydrolyzed lecithin contains two fatty acids, and the fatty acid moiety can be different at the two positions on the phospholipid molecule. The fatty acid composition can have an effect on the stability and functionality of the lecithin. Changes in the fatty acid composition can be done through transesterification (165). Transesterification using lipases can be used for the addition of polyunsaturated fatty acids to lecithin to enhance the essential fatty acid profile, or to improve functionality (166). 

Egg replacers. Lecithins are used in conjunction with dairy and vegetable proteins in an attempt to functionally mimic the lipoprotein complex of egg yolks. A coagulable egg replacer based on whey protein, polyunsaturated fat, and lecithin has been described (31). Another formulation included soy and wheat flour blended with oil, lecithin, carrageenan, and polysorbate 60 to replace up to 75% dry or liquid eggs in a variety of mixes and prepared foods (31). Dashiell (31) also reported on a lipoprotein complex formed from soy isolate, oil, carbohydrate, and various emulsifiers, which is claimed to be useful for whole or partial replacement of egg yolks in baked goods. 

The primary mechanism by which lecithin lowers cholesterol is by decreasing the absorption of dietary cholesterol from the intestine to the blood stream (269, 270). There is also evidence that lecithin intake lowers cholesterol by increasing the amount of cholesterol used in the production of bile salts (271). As more cholesterol is used for bile salt synthesis, less is available to reach the blood stream and damage blood vessels. Lecithin also contributes polyunsaturated fatty acids to the diet, which may help control blood cholesterol levels. 

The fatty acid composition of muscle lipids may show quantitative alterations in diseased muscle. Thus lecithin isolated from human dystrophic muscle had an increased amount of oleic but diminished linoleic acid (Tl). Changes have been recorded also in the fatty acid composition of lecithin from denervated muscle (PI). Recently it has been reported (K16) that the fatty acid pattern of muscle phosphatides from patients with the autosomal dominant form of myotonia congenita differed markedly from that of the autosomal recessive form and from the normal. Tani and his co-workers (F7) have made a detailed study of the phospholipids of normal and dystrophic mouse tissues. In normal mice phosphatidylcholine and phosphatidylethanolamine from skeletal and heart muscles had a very high content of 20-22-carbon polyunsaturated acids, in comparison with those for other tissues the most abundant was docosahexaenoic acid. In dystrophic mice there was a sharp decrease in the proportion of docosahexaenoic acid in the phosphoglycerides from skeletal and heart muscles, suggesting the likelihood of important alterations in muscle membranes. Somewhat similar studies have been reported by Owens (05), who also observed a fall in the proportion of docosahexaenoic acid, mainly in the phosphatidylcholine -j- choline plasmalogen fraction. 

Richards H, Thomas CP, Bowen JL, Heard CM. In-vitro transcutaneous delivery of ketoprofen and polyunsaturated fatty acids from a pluronic lecithin organogel vehicle containing fish oil. J Pharm Pharmacol. 58(7) (2006) 903-908. 

Table 9.2. Effect of iron and EDTA on the oxidation of an oil-in-water lecithin emulsion prepared with mackerel oil containing long-chain polyunsaturated fatty acids at 40°C=...

Emulsions were prepared with 5% mackerel oil, 1% lecithin and homogenized with phosphate-citrate buffer (25 mM, pH 6.6). The mackerel oil contained 40.2% polyunsaturated fatty acids consisting of 9.7% EPA and 14.5% DHA, and 11 ppm of a-tocopherol. 

---