Lecithin

Synonyms: E322; egg lecithin; LSC 5050; LSC 6040; mixed soybean phosphatides; ovolecithin; Phosal 53 MCT; Phospholipon 100 H; ProKote LSC; soybean lecithin; soybean phospholipids; Sternpur; vegetable lecithin.

Description: Lecithins vary greatly in their physical form, from viscous semiliquids to powders, depending upon the free fatty acid content. They may also vary in color from brown to light yellow, depending upon whether they are bleached or unbleached or on the degree of purity. When they are exposed to air, rapid oxidation occurs, also resulting in a dark yellow or brown color. Lecithins have practically no odor. Those derived from vegetable sources have a bland or nutlike taste, similar to that of soybean oil.

Chemical Name: Lecithin

Emollient; emulsifying agent; solubilizing agent.

• Lecithins are used in a wide variety of pharmaceutical applications.

• They are also used in cosmetics and food products.

• Lecithins are mainly used in pharmaceutical products as dispersing, emulsifying, and stabilizing agents, and are included in intramuscular and intravenous injections, parenteral nutrition formulations, and topical products such as creams and ointments.

• Lecithins are also used in suppository bases, to reduce the brittleness of suppositories, and have been investigated for their absorption-enhancing properties in an intranasal insulin formulation.

• Lecithins are also commonly used as a component of enteral and parenteral nutrition formulations. There is evidence that phosphatidylcholine (a major component of lecithin) is important as a nutritional supplement to fetal and L Lecithin 385 infant development.

• Furthermore, choline is a required component of FDA-approved infant formulas.

• Other studies have indicated that lecithin can protect against alcohol cirrhosis of the liver, lower serum cholesterol levels, and improve mental and physical performance.

• Liposomes in which lecithin is included as a component of the bilayer have been used to encapsulate drug substances; their potential as novel delivery systems has been investigated.

• This application generally requires purified lecithins combined in specific proportions.

• Therapeutically, lecithin and derivatives have been used as a pulmonary surfactant in the treatment of neonatal respiratory distress syndrome.

Incompatible with esterases owing to hydrolysis.

Lecithin is a component of cell membranes and is therefore consumed as a normal part of the diet. Although excessive consumption may be harmful, it is highly biocompatible and oral doses of up to 80 g daily have been used therapeutically in the treatment of tardive dyskinesia. When used in topical formulations, lecithin is generally regarded as a nonirritant and nonsensitizing material. The Cosmetic Ingredients Review Expert Panel (CIR) has reviewed lecithin and issued a tentative report revising the safe concentration of the material from 1.95% to 15.0% in rinse-off and leave-in products. They note, however, that there are insufficient data to rule on products that are likely to be inhaled.

Observe normal precautions appropriate to the circumstances and quantity of material handled. Lecithins may be irritant to the eyes; eye protection and gloves are recommended.

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