Sphingolipids 22 waxes

What are waxes and sphingolipids Waxes are esters of long-chain fatty acids and long-chain alcohols. Sphingolipids do not contain glycerol but have a loug-chain alcohol called sphingosine as part of their structure iustead. 

Lipids are a large class of materials that includes fatty acids, glycerides, phospholipids, sphingolipids, waxes, and sterols. These compounds are usually insoluble in water, or... 

The products are fatty acids, CH3(CH2) COOH, which in turn can give rise to amines and alcohols. Lipids containing fatty acids include the glycerolipids, the sphingolipids, and waxes. 

Tetracosanoic Lignoceric 84.2 Widespread as a constituent of sphingolipids, minor acid in some seed triacylglycerols and plant waxes. 

Hydroxy or a-hydroxy acids have been shown to occur in sphingolipids, skin lipids, wool wax, bacterial cell wall lipids and in some seed oils. 3-Hydroxy or 3-hydroxy acids are present in bacterial lipids. 

Lipids are bioorganic substances related to fatty acid esters and include a variety of compounds such as glycerol esters, waxes, phosphoglycerides, sphingolipids, natural hydrocarbons, some vitamins, etc. This diversity of compounds is explained by the fact that initially the term lipids was used to describe natural bioorganic substances soluble in hydrocarbons and insoluble in water. Lipids include both small molecules and polymeric materials. Because some simple lipids are not polymeric, their pyrolysis will be discussed only to the extent of being associated with the pyrolysis of complex lipids. However, non-polymeric lipids are commonly associated with polymeric ones, and pyrolytic techniques were frequently applied on the whole lipid without separation for purposes such as classification or identification of microorganisms based on the pyrolysis pattern of their lipids [1]. 

The structures of lipids are quite varied triacylglycerols (fats and oils), waxes, phospholipids, sphingolipids, steroids, eicosanoids, fat soluble vitamins, and pigments. Some lipids are simple in structure while others are more complex. Among these molecules are those which are esters in nature and therefore saponifiable in aqueous base. Others are nonsaponifiable. Many are completely nonpolar while others are amphipathic, that is, they have a polar/nonpolar nature. 

Lipids are a diverse group of biomolecules that dissolve in nonpolar solvents. They can be separated into the following classes fatty acids and their derivatives, triacylglycerols, wax esters, phospholipids, lipoproteins, sphingolipids, and the isoprenoids. 

Nonglyceride lipids consist of sphingolipids, steroids, and waxes. Sphingomyelin is a component of the myelin sheath around cells of the central nervous system. The steroids... 

Lipids are a class of nonpolar molecules that include the fats, cholesterol, fatty acids, lipid-soluble vitamins, waxes, soaps, glycerophospholipids, sphingolipids, and others. Lipids are found in the membranes of cells, the endoplasmic reticulum, and in specialized fat storage cells called adipocytes. 

Lipids are one of the major structural components in living cells and encompass a myriad different types of compound. In most cases, they possess only one common property, which is their solubility in non-polar solvents such as chloroform, ether, hydrocarbons or alcohols and insolubility in water (Davenport and Johnson, 1971). Some of the types of compounds that are classified as lipids include fatty acids, glycerides, waxes, cholesterol esters, phosphoglycerides and sphingolipids. 

Hydroxy acids (Section 1.9) do not occur very extensively though they are present in sphingolipids, stillin-gia oil (Section 3.3.34), waxes (Section 3.6) and in fungal (Section 3.7) and bacterial lipids (Section 3.8). 

Other lipid types which have been found in bacteria include wax esters, hydrocarbons, sphingolipids, steroids and terpenoids. These occur sporadically, however, and are seldom major components. An obvious exception is the presence of carotenoids and the ornithine-containing lipid of purple photosynthetic bacteria. Further details of minor lipid components of bacteria can be found in Razin and Rottem (1982), Shaw (1974) and Goldfine (1972). 

In animal tissues, 2-hydroxy fatty acids are frequent components of the sphingolipids and they are also present in skin and wool wax. 4- and 5-Hydroxy fatty acids, which form lactones on hydrolysis, and keto acids are found in cow s milk. As part of the "arachidonic acid cascade", a large number of hydroperoxy, hydroxy and epoxy fatty acids... 

Hydroxy fatty acids with 16-26 carbon atoms are important components of animal sphingolipids (see Section 3.5) and plant waxes occurring on the surface of leaf vegetables. In addition,... 

An all-embracing term referring to any compound that is soluble in chloroform, benzene, petroleum, or ether. Included are fats, oils, waxes, sterols, and complex compounds such as phospholipids and sphingolipids. There are three basic types of lipids—simple lipids, compound lipids, and derived lipids. When fatty acids are esterified with alcohols, simple lipids result. If compounds such as choline or serine are esterified to alcohols in addition to fatty acids, compound lipids result. The third type of lipid, derived lipids, result from the hydrolysis of simple and compound lipids. The sterols and fatty acids are derived lipids. 

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