Nervonic acid

Formic acid Acetic acid Propionic acid Butyric acid Capric acid Palmitic acid Palmitoleic acid Stearic acid Oleic acid Linoleic acid -jLinolenic acid Arachidonic acid Lignoceric acid Nervonic acid... 

Nervonic acid m-15-Tetracosenoic acid 24 Elasmobranch fish, brain... 

Elongation by two carbon atoms occurs commonly in fatty acid biosynthesis. It is a variant of de novo chain-lengthening and occurs with acetyl or malonyl CoA or ACP derivatives. The substrate is any preformed saturated or unsaturated acid. For example, erucic (22 1) in high-emcic acid rapeseed oil and nervonic acid (24 1) in seed oil are formed from oleic acid by two and three elongations, respectively ... 

Honesty (Lunaria annua). This seed oil contains significant levels of erucic (22 1, 41%) and nervonic acids (24 1, 22%) and is being studied as a new crop because it is a good source of the latter acid, which may be useful in the treatment of demyelinating dizease (120). 

Honesty seed oil (Lunaria biennis) is characterized by its high levels of monoene acids, including 18 1 (23%), 22 1 (46%), and 24 1 (23%). It is being developed as a commercial crop for nutritional research based on its significant level of nervonic acid (24 1) (120). 

From saponification of cerebrosides, lipids found in the membranes of brain and nerve cells therc is obtained nervonic acid. This acid rapidly decolorizes dilute KMn04 and Br2/CCl4 solutions. Hydrogenation in the presence of nickel yields tetracosanoic acid, W-C23H47COOH. Vigorous oxidation of nervonic acid yields one acid of neutralization equivalent 156 3 and another acid of neutralization equivalent 137 2. What structure or structures are possible for nervonic acid ... 

Nervonic acid, cis- or /rn/w-CH3(CH2)7CH- H(CH2>i3COOH (actually, trans), 2. Transesteriiication to more random distribution of acyl groups among glyceride molecules. 3. Hybrid (allylic) free radical is intermediate. 4. Spermaceti, /i-hexadecyl /r-hexadecanoate. 6. Cleavage of monoanion as dipolar ion (or with simultaneous trans-... 

Solution Since nervonic acid rapidly decolorizes dilute KMnOit and Br2/CCli solutions, we know that this compound contains carbon-carbon double bonds. 

Nervonic acid must be a straight chain monocarboxylic acid because its hydrogenation product is also straight chained. Hence nervonic acid is oxidized to a straight chained monocarboxylic acid and a straight chained di-carboxylic acid. The MW of tetracosanoic acid (n-C2 sHi 7-COOH) is 368 nervonic acid must have a molecular formula of n-C2 sHi 5-COOH with a MW of 366. This is because it contains only one carbon-carbon double bond. The MW of a dicarboxylic acid is twice its neutralization equivalent (NE). If the dicarboxylic acid produced by the oxidation of nervonic acid has an NE = 156 3, its MW = 312 6. 

The MW of a monocarboxylic acid is equal to its NE. Hence the MW of the monocarboxylic acid produced by oxidation of nervonic acid would be 137 2. Addition of the MW s of the two acids should give us the MW of nervonic acid plus 64 (four times the weight of oxygen) ... 

Since the oxidation of nervonic acid cleaved its lone carbon-carbon double bond to yield two carboxylic acids, the joining of these two acids should give us the structure of nervonic acid. In joining these acids, we must remove four oxygens to give us the carbon-carbon double bond of nervonic acid. 

As we can see, both the cis and trans structures are possible it is actually the trans isomer that is called nervonic acid. The hydrogenation and oxidation reactions were as follows ... 

The main difference between the various sphingomyelins lies in the nature of the FA, which can have a chain length between 16 and 24 carbon atoms. Lignoceric acid and nervonic acid are abundant. The nature of the fats consumed may influence the ratio of the different FA incorporated in the different sphin-golipids of the body. The physiological consequences of this influence, however, remain unknown. 

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