Oleic acid

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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.

Oleic acid
Oleic acid
IUPAC name (9Z)-octadec-9-enoic acid
Other names (9Z)-Octadecenoic acid
(Z)-Octadec-9-enoic acid
cis-9-octadecenoic acid
cis-Δ9-octadecenoic acid
Oleic acid
18:1 cis-9
Identifiers
CAS number [112-80-1]
SMILES CCCCCCCC\C=C/CCCCCCC(OH)=O
Properties
Molecular formula C18H34O2
Molar mass 282.4614 g/mol
Appearance Pale yellow or brownish yellow
oily liquid with lard-like odor
Density 0.895 g/mL
Melting point

13-14°C (286 K)
Boiling point

360°C (633 K) (760mm Hg)[2]
Solubility in water Insoluble in water; soluble in Methanol
Hazards
MSDS ScienceLab.com
Except where noted otherwise, data are given for
materials in their standard state
(at 25 °C, 100 kPa)
Infobox disclaimer and references


Contents

[edit] 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, açaí, 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 showed as a cool trick in high school science classes.

[edit] Chemistry

Reduction of oleic acid at the carboxyl end yields oleyl alcohol.

Salts of oleic acid are called oleates.

[edit] References

  1. ^ 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.
  2. ^ Oleic acid, Chemical Laboratory Information Profile, American Chemical Society
  3. ^ 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.
  4. ^ 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]
  5. ^ 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. 
  6. ^ 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.

[edit] External links


v • d • e
Lipids: fatty acids
Saturated
n−3 Unsaturated
n−6 Unsaturated
n−9 Unsaturated
Oleic • Erucic • Nervonic