This high purity nonanoic acid is ideal as a standard and for biological studies. Odd numbered fatty acids occur in small amounts in mammals but are found in much larger amounts in bacteria and in some plants (especially in pelargonium) and lower animals. Due to difficulties in their identification the properties and functions of odd numbered fatty acids have not been fully studied, but with better analytical techniques and high purity standards they are now gaining more prevalence in research.1 Odd numbered fatty acids are found in small amounts acylated to various sphingolipids where they have unique properties and functions.2 Microbial fatty acid profiles, which often contain significant amounts of odd numbered fatty acids, are unique from one species to another and can therefore be used in the determination of bacterial identity. Nonanoic acid and its esters are used as herbacides (both as the free acid and as ammonium nonanoate), flavorings, and in the biosynthesizing of polyhydroxyalkenoates. It induces irritancy of the skin but both its mechanism and gene activation are different from other skin irritants.3 Nonanoic acid has been found to be a fungal self inhibitor of Rhizopus oligosporus.4 Sphingolipids are normally acylated with long-chain fatty acids and are critical in many biological functions. When acylated with shorter fatty acids these sphingolipids can more easily cross the cell membrane barrier. Nonanoic acid is a saturated fatty acid and saturated fatty acids have been found to cause moderate risk of coronary heart disease as compared with polyunsaturated fatty acids and they significantly lower the total cholesterol/high density lipoprotein-cholesterol ratio as compared with carbohydrates.5
