| Abstract | Naturally occurring very long chain fatty acids (fatty acids with more than 22 carbon atoms) include the main families: saturated, monounsaturated, methylene-interrupted and non methylene interrupted polyunsaturated fatty acids (VLCPUFA), and hydroxy acids. There is a growing interest in one of these families, methylene-interrupted VLCPUFA, especially due to their involvement in the biosynthesis of docosahexaenoic acid in mammals. Allegedly the best known representative of this family is nisinic acid, 24:6n-3. Despite the fact that systematic studies of methylene-interrupted VLCPUFA were started at the brink of the twentieth century, our knowledge of these is still very limited. Elevated levels of these acids were found in mammalian reproductive organs and retina, but it is likely that virtually all mammalian cells contain these acids. Dietary sources of nisinic and related acids include marine fish and a number of Omega-3 food supplements. Since these acids were only occasionally looked at as fish constituents, there remains significant controversy about their content, which varied for nisinic acids from not detected to up to 13% of total fatty acids in flesh triacylglycerols in flathead flounder reported recently. The progress in studies of VLCPUFA is hindered by the fact that they are not widely known, often ignored, or even not observed when routine analytical techniques (suitable for shorter-chain acids) are used, and also by a lack of commercially available reference compounds. Considering the fact that disturbances in VLCPUFA metabolism may lead to serious pathologies, this situation cannot be considered as satisfactory. © 2011 by Nova Science Publishers, Inc. All Rights Reserved. |
