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Phosphatides (phospholipids)

Phosphatides (also called phospholipids) are a group of lipid compounds which yield, on hydrolysis, phosphoric acid, an alcohol, a fatty acid, and a nitrogenous base. Phosphatides are one of several byproducts recovered during the purification of vegetable oil. Vegetable oils are typically obtained by pressing or extracting the oil seeds of plants such as corn or soybeans. Vegetable oils primarily consist of triglycerides, also termed triacylglycerols. In addition to triglycerides, vegetable oils also contain several other compounds such as mono- and di-glycerides, tocopherols, sterols, and sterol esters. Phospholipids are distributed widely in organisms, existing especially as constituents of cell membranes, and are considered to serve a role in various important physiological actions through controlling the function of membranes. The phosphatides may be divided into two main groups, viz. hydratable and non-hydratable phosphatides. The hydratable phosphatides can be removed from the oil by treatment with water, whereby the phosphatides become hydrated and insoluble in the oil, from which they can easily be removed by applying simple separating methods. Phosphatides are widely distributed in nature and include such compounds as phosphatidyl choline (chemical lecithin), phosphatidyl ethanolamine (cephalin), and the inositol phosphatides. The lecithin refers to a product derived from vegetable oils, especially soybean oil. Specific chemical components of phosphatides present in vegetable oil include phosphatidyl choline. Phosphatides are derived from a number of animal and vegetable sources, with the largest source being crude soybean oil. Phosphatides are believed to possess significant nutritional benefits. For example, it has been suggested that the ingestion of phosphatides may aid digestion and reduce cholesterol. The use of natural phospholipids (from soy or animal tissues) is particularly preferred for cosmetic applications, while for more specifically pharmaceutical formulations the use of a chemically homogeneous and defined phospholipid, e.g. distearoyl phosphatidylcholine, may be more appropriate.

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