Oleic acid is a monounsaturated omega-9 fatty acid found in various animal and vegetable sources. It has the formula C18H34O2 (or CH3(CH2)7CH=CH(CH2)7COOH).[1] The saturated form of this acid is stearic acid.
Occurrence
Oleic acid makes up 55-80% of olive oil, though there may be only 0.5-2.5% or so as actual free acid, and 15-20% of grape seed oil and sea buckthorn oil.[3] The Brazilian palmberry, açaÃ, contains one of the highest contents known for oleic acid in the pulp of a fruit (56%)[4].
Oleic acid is emitted by the decaying corpses of a number of insects, including bees and Pogonomyrmex ants and triggers the instincts of living workers to remove the dead bodies from the hive. If a live bee[5] or ant[6] is daubed with oleic acid, it is dragged off as if it were dead.
It can also be noted that if dropped onto water, oleic acid spreads out into a very thin layer, only a molecule thick if allowed (This requires much dilution in most cases). This is often shown as a cool trick in high school science classes.
Chemistry
Reduction of oleic acid at the carboxyl end yields oleyl alcohol.
Salts of oleic acid are called oleates.
References
- ^ Bishop, Paul L. (2000). Pollution Prevention: Chapter 2 - Properties and Fates of Environmental Contaminants, instructional slides to accompany Pollution Prevention:Fundamentals and Practice, by Paul L. Bishop (ISBN 0-07-366147-3). Retrieved 2005-03-07.
- ^ Oleic acid, Chemical Laboratory Information Profile, American Chemical Society
- ^ Li, Thomas S. C. (1999). Sea buckthorn: New crop opportunity, from Perspectives on new crops and new uses by J. Janeck (ed.) Retrieved 2006-10-28.
- ^ Schauss AG, Wu X, Prior RL, Ou B, Patel D, Huang D, Kababick JP. Phytochemical and nutrient composition of the freeze-dried amazonian palm berry, Euterpe oleraceae Mart. (acai). J Agric Food Chem. 2006 Nov 1;54(22):8598-603. [1]
- ^ Anies Hannawati Purnamadjaja, R. Andrew Russell (2005). "Pheromone communication in a robot swarm: necrophoric bee behaviour and its replication". Robotica 23 (6): 731–742. doi:10.1017/S0263574704001225.
- ^ Ayasse, M, Paxton, R (2002) Brood protection in social insects. In: Hilker, M, Meiners, T (eds.). Chemoecology of Insect Eggs and Egg Deposition. Blackwell, Berlin, 117-148.
External links
This page was last modified on 25 June 2008, at 02:49.