Lipids and Lipidomics

Lipids are one of the main constituents of biological cells and the major components of lipoproteins in serum. Lipids are often conjugated with carbohydrates, which are known as lipopolysaccharides. Many lipid chemists classify lipids into polar and nonpolar lipids based on the overall hydrophobicity of the lipids. The nonpolar lipids include fatty acids and their derivatives, glycerol-derived lipids, and steroids. The polar lipids usually contain a polar head group, such as phosphocholine in choline glycerophospholipids, and are usually soluble in relatively polar solvents, such as alcohol, and even water. The entire collection of chemically distinct lipid species in a cell, an organ, or a biological system has been referred to as a lipidome. Lipids are considered as biological metabolites. Hence, lipidomics is covered under the umbrella of the general field of metabolomics. Lipidomics is a distinct discipline because of the uniqueness and functional specificity of lipids relative to other metabolites.