Oleic acid is a fatty acid that occurs naturally in various animal and vegetable fats and oils. It is an odorless, colorless oil, although commercial samples may be yellowish. In chemical terms, oleic acid is classified as a monounsaturated omega-9 fatty acid, abbreviated with a lipid number of 18:1 cis-9. It has the formula CH3(CH2)7CH=CH(CH2)7COOH.[2] The name derives from the Latin word oleum, which means oil.[3] It is the most common fatty acid in nature.[4] The salts and esters of oleic acid are called oleates.

Oleic acid
Oleic acid
Preferred IUPAC name
(9Z)-Octadec-9-enoic acid
Other names
Oleic acid
(9Z)-Octadecenoic acid
(Z)-Octadec-9-enoic acid
cis-9-Octadecenoic acid
cis9-Octadecenoic acid
18:1 cis-9
3D model (JSmol)
ECHA InfoCard 100.003.643 Edit this at Wikidata
  • InChI=1S/C18H34O2/c1-2-3-4-5-6-7-8-9-10-11-12-13-14-15-16-17-18(19)20/h9-10H,2-8,11-17H2,1H3,(H,19,20)/b10-9- ☒N
  • InChI=1/C18H34O2/c1-2-3-4-5-6-7-8-9-10-11-12-13-14-15-16-17-18(19)20/h9-10H,2-8,11-17H2,1H3,(H,19,20)/b10-9-
Molar mass 282.468 g·mol−1
Appearance colorless oily liquid with lard-like odor
Density 0.895 g/mL
Melting point 13 to 14 °C (55 to 57 °F; 286 to 287 K)
Boiling point 360 °C (680 °F; 633 K)[1]
Solubility in Ethanol Soluble
-208.5·10−6 cm3/mol
Safety data sheet JT Baker
NFPA 704 (fire diamond)
Related compounds
Related compounds
Elaidic acid
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
☒N verify (what is checkY☒N ?)
Infobox references


Fatty acids (or their salts) often do not occur as such in biological systems. Instead fatty acids such as oleic acid occur as their esters, commonly triglycerides, which are the greasy materials in many natural oils. Oleic acid is the most common monounsaturated fatty acid in nature. It is found in fats (triglycerides), the phospholipids that make membranes, cholesterol esters, and wax esters.[5]

Triglycerides of oleic acid comprise the majority of olive oil (about 70%). Olive oil exceeding 2% free oleic acid is graded unfit for human consumption.[6] It also makes up 59–75% of pecan oil,[7] 61% of canola oil,[8] 36–67% of peanut oil,[9] 60% of macadamia oil, 20–80% of sunflower oil,[10] 15–20% of grape seed oil, sea buckthorn oil, 40% of sesame oil,[2] and 14% of poppyseed oil. High oleic variants of plant sources such as sunflower (~80%) and canola oil (70%) also have been developed.[10] It also comprises 22.18% of the fats from the fruit of the durian species, Durio graveolens.[11] Karuka contains 52.39% oleic acid.[12] It is abundantly present in many animal fats, constituting 37 to 56% of chicken and turkey fat,[13] and 44 to 47% of lard.

Oleic acid is the most abundant fatty acid in human adipose tissue,[14] and second in abundance in human tissues overall, following palmitic acid.

Production and chemical behaviorEdit

The biosynthesis of oleic acid involves the action of the enzyme stearoyl-CoA 9-desaturase acting on stearoyl-CoA. In effect, stearic acid is dehydrogenated to give the monounsaturated derivative, oleic acid.[5]

Oleic acid undergoes the reactions of carboxylic acids and alkenes. It is soluble in aqueous base to give soaps called oleates. Iodine adds across the double bond. Hydrogenation of the double bond yields the saturated derivative stearic acid. Oxidation at the double bond occurs slowly in air, and is known as rancidification in foodstuffs and as drying in coatings. Reduction of the carboxylic acid group yields oleyl alcohol. Ozonolysis of oleic acid is an important route to azelaic acid. The coproduct is nonanoic acid:[15]

H17C8CH=CHC7H14CO2H + 4"O" → HO2CC7H14CO2H + H17C8CO2H

Esters of azelaic acid find applications in lubrications and plasticizer.

Related compoundsEdit

The trans isomer of oleic acid is called elaidic acid or trans-9-octadecenoic acid. These isomers have distinct physical properties and biochemical properties. Elaidic acid, the most abundant trans fatty acid in diet, appears to have an adverse effect on health.[16] A reaction that converts oleic acid to elaidic acid is called elaidinization.

Another naturally occurring isomer of oleic acid is petroselinic acid.

In chemical analysis, fatty acids are separated by gas chromatography of their methyl ester derivatives. Alternatively, separation of unsaturated isomers is possible by argentation thin-layer chromatography.[17]

In ethenolysis, methyl oleate, the methyl ester of the acid, converts to 1-decene and methyl 9-decenoate:[18]

CH3(CH2)7CH=CH(CH2)7CO2Me + CH2=CH2 → CH3(CH2)7CH=CH2 + MeO2C(CH2)7CH=CH2


Oleic acid is used as a component in many foods, in the form of its triglycerides. It is a component of the normal human diet, being a part of animal fats and vegetable oils.

Oleic acid as its sodium salt is a major component of soap as an emulsifying agent. It is also used as an emollient.[19] Small amounts of oleic acid are used as an excipient in pharmaceuticals, and it is used as an emulsifying or solubilizing agent in aerosol products.[20]

Niche usesEdit

Oleic acid is used to induce lung damage in certain types of animals for the purpose of testing new drugs and other means to treat lung diseases. Specifically in sheep, intravenous administration of oleic acid causes acute lung injury with corresponding pulmonary edema.[21]

Oleic acid is used as a soldering flux in stained glass work for joining lead came.[22]

Oleic acid is widely used in the solution phase synthesis of nanoparticles, functioning as a kinetic knob to control the size and morphology of nanoparticles.[23]

Health effectsEdit

Oleic acid is the topmost monounsaturated fat in the human diet.[24] Monounsaturated fat consumption has been associated with decreased low-density lipoprotein (LDL) cholesterol, and possibly with increased high-density lipoprotein (HDL) cholesterol.[25] Oleic acid may be responsible for the hypotensive (blood pressure reducing) effects of olive oil that is considered a health benefit.[26] A 2017 review found that diets enriched in oleic acid are beneficial for regulating body weight.[27]

The FDA has approved a health claim on reduced risk of coronary heart disease for high oleic (> 70% oleic acid) oils.[28] Some oil plants have cultivars bred to increase the amount of oleic acid in the oils. In addition to providing a health claim, the heat stability and shelf life may also be improved, but only if the increase in monounsaturated oleic acid levels correspond to a substantial reduction in polyunsaturated fatty acid (especially α-Linolenic acid) content.[29] When the saturated fat or trans fat in a fried food is replaced with a stable high oleic oil, consumers may be able to avoid certain health risks associated with consuming saturated fat and trans fat.[30][31]

See alsoEdit


  1. ^ Young, Jay A. (2002). "Chemical Laboratory Information Profile: Oleic Acid". Journal of Chemical Education. 79 (1): 24. Bibcode:2002JChEd..79...24Y. doi:10.1021/ed079p24.
  2. ^ a b Thomas, Alfred (2000). "Fats and Fatty Oils". Ullmann's Encyclopedia of Industrial Chemistry. doi:10.1002/14356007.a10_173. ISBN 978-3-527-30673-2.
  3. ^ Bailey and Bailey, Dorothy and Kenneth (1929). "An Etymological Dictionary of Chemistry and Mineralogy". Nature. 124 (3134): 789–790. Bibcode:1929Natur.124..789V. doi:10.1038/124789b0. S2CID 4024133.
  4. ^ "9-Octadecenoic acid". PubChem, National Center for Biotechnology Information, US National Library of Medicine. 14 July 2018. Retrieved 19 July 2018.
  5. ^ a b Ntambi, James M.; Miyazaki, Makoto (2003). "Recent insights into stearoyl-CoA desaturase-1". Current Opinion in Lipidology. 14 (3): 255–61. doi:10.1097/00041433-200306000-00005. PMID 12840656. S2CID 45954457.
  6. ^ "Olive Oil and Olive-Pomace Oil Grades and Standards | Agricultural Marketing Service". www.ams.usda.gov. Retrieved 2016-01-20.
  7. ^ Villarreal-Lozoya, Jose E.; Lombardini, Leonardo; Cisneros-Zevallos, Luis (2007). "Phytochemical constituents and antioxidant capacity of different pecan Carya illinoinensis (Wangenh.) K. Koch] cultivars". Food Chemistry. 102 (4): 1241–1249. doi:10.1016/j.foodchem.2006.07.024. 
  8. ^ "Comparison of Dietary Fats Chart". Canola Council of Canada. Archived from the original on 2008-06-06. Retrieved 2008-09-03.
  9. ^ Moore, K. M.; Knauft, D. A. (1989). "The Inheritance of High Oleic Acid in Peanut". The Journal of Heredity. 80 (3): 252–3. doi:10.1093/oxfordjournals.jhered.a110845. 
  10. ^ a b "Nutrient database, Release 25". United States Department of Agriculture.(NDB ID: 04678, 04584)
  11. ^ Nasaruddin, Mohd hanif; Noor, Noor Qhairul Izzreen Mohd; Mamat, Hasmadi (2013). "Komposisi Proksimat dan Komponen Asid Lemak Durian Kuning (Durio graveolens) Sabah" [Proximate and Fatty Acid Composition of Sabah Yellow Durian (Durio graveolens)] (PDF). Sains Malaysiana (in Malay). 42 (9): 1283–1288. ISSN 0126-6039. OCLC 857479186. Retrieved 28 November 2017.
  12. ^ Purwanto, Y.; Munawaroh, Esti (2010). "Etnobotani Jenis-Jenis Pandanaceae Sebagai Bahan Pangan di Indonesia" [Ethnobotany Types of Pandanaceae as Foodstuffs in Indonesia]. Berkala Penelitian Hayati (in Indonesian). 5A: 97–108. doi:10.5072/FK2/Z6P0OQ. ISSN 2337-389X. OCLC 981032990. Archived from the original (PDF) on 29 October 2018. Retrieved 25 October 2018.
  13. ^ Nutter, Mary K.; Lockhart, Ernest E.; Harris, Robert S. (1943). "The chemical composition of depot fats in chickens and turkeys". Oil & Soap. 20 (11): 231–4. doi:10.1007/BF02630880. S2CID 84893770. 
  14. ^ Kokatnur, MG; Oalmann, MC; Johnson, WD; Malcom, GT; Strong, JP (1979). "Fatty acid composition of human adipose tissue from two anatomical sites in a biracial community". The American Journal of Clinical Nutrition. 32 (11): 2198–205. doi:10.1093/ajcn/32.11.2198. PMID 495536. 
  15. ^ Cornils, Boy; Lappe, Peter (2000). "Dicarboxylic Acids, Aliphatic". Ullmann's Encyclopedia of Industrial Chemistry. doi:10.1002/14356007.a08_523. ISBN 978-3-527-30673-2.
  16. ^ Tardy, Anne-Laure; Morio, Beatrice; Chardigny, Jean-Michel; Malpuech-Brugere, Corinne (2011). "Ruminant and industrial sources of trans-fat and cardiovascular and diabetic diseases". Nutrition Research Reviews. 24 (1): 111–117. doi:10.1017/S0954422411000011. PMID 21320382.
  17. ^ Breuer, B.; Fock, H. P. (1987). "Separation of fatty acids or methyl esters including positional and geometric isomers by alumina argentation thin-layer chromatography". J. Chromatogr. Sci. 25 (7): 302–306. doi:10.1093/chromsci/25.7.302. PMID 3611285.
  18. ^ Marinescu, Smaranda C.; Schrock, Richard R.; Müller, Peter; Hoveyda, Amir H. (2009). "Ethenolysis Reactions Catalyzed by Imido Alkylidene Monoaryloxide Monopyrrolide (MAP) Complexes of Molybdenum". J. Am. Chem. Soc. 131 (31): 10840–10841. doi:10.1021/ja904786y. PMID 19618951.
  19. ^ Carrasco, F. (2009). "Ingredientes Cosméticos". Diccionario de Ingredientes (4th ed.). p. 428. ISBN 978-84-613-4979-1.
  20. ^ Smolinske, Susan C. (1992). Handbook of Food, Drug, and Cosmetic Excipients. pp. 247–8. ISBN 978-0-8493-3585-3.
  21. ^ Julien, M; Hoeffel, JM; Flick, MR (1986). "Oleic acid lung injury in sheep". Journal of Applied Physiology. 60 (2): 433–40. doi:10.1152/jappl.1986.60.2.433. PMID 3949648.
  22. ^ Duncan, Alastair (2003). The Technique of Leaded Glass. p. 77. ISBN 978-0-486-42607-5.
  23. ^ Yin, Xi; Shi, Miao; Wu, Jianbo; Pan, Yung-Tin; Gray, Danielle L.; Bertke, Jeffery A.; Yang, Hong (11 September 2017). "Quantitative Analysis of Different Formation Modes of Platinum Nanocrystals Controlled by Ligand Chemistry". Nano Letters. 17 (10): 6146–6150. Bibcode:2017NanoL..17.6146Y. doi:10.1021/acs.nanolett.7b02751. PMID 28873317.
  24. ^ Schwingshackl, L., Hoffmann, G. (2014). "Monounsaturated fatty acids, olive oil and health status: a systematic review and meta-analysis of cohort studies". Lipids in Health and Disease. 13: 154. doi:10.1186/1476-511X-13-154. PMC 4198773. PMID 25274026.CS1 maint: multiple names: authors list (link)
  25. ^ "You Can Control Your Cholesterol: A Guide to Low-Cholesterol Living". Merck & Co. Inc. Archived from the original on 2009-03-03. Retrieved 2009-03-14.
  26. ^ Teres, S.; Barcelo-Coblijn, G.; Benet, M.; Alvarez, R.; Bressani, R.; Halver, J. E.; Escriba, P. V. (2008). "Oleic acid content is responsible for the reduction in blood pressure induced by olive oil". Proceedings of the National Academy of Sciences. 105 (37): 13811–6. Bibcode:2008PNAS..10513811T. doi:10.1073/pnas.0807500105. JSTOR 25464133. PMC 2544536. PMID 18772370.
  27. ^ Tutunchi, Helda; Ostadrahimi, Alireza; Saghafi-Asl, Maryam (2020). "The Effects of Diets Enriched in Monounsaturated Oleic Acid on the Management and Prevention of Obesity: a Systematic Review of Human Intervention Studies". Advances in Nutrition. 11 (4): 864–877. doi:10.1093/advances/nmaa013. PMC 7360458. PMID 32135008.CS1 maint: multiple names: authors list (link)
  28. ^ Nutrition, Center for Food Safety and Applied (20 December 2019). "FDA Completes Review of Qualified Health Claim Petition for Oleic Acid and the Risk of Coronary Heart Disease". FDA.
  29. ^ Aladedunye, Felix; Przybylski, Roman (December 2013). "Frying stability of high oleic sunflower oils as affected by composition of tocopherol isomers and linoleic acid content". Food Chemistry. 141 (3): 2373–2378. doi:10.1016/j.foodchem.2013.05.061. PMID 23870970.
  30. ^ "High-oleic canola oils and their food applications". The American Oil Chemists' Society.
  31. ^ Trans Fat Task Force (June 2006). TRANSforming the Food Supply. ISBN 0-662-43689-X. Retrieved 7 January 2007.

External linksEdit