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Record Information
StatusDetected and Quantified
Creation Date2005-11-16 15:48:42 UTC
Update Date2020-03-19 21:31:09 UTC
Secondary Accession Numbers
  • HMDB05047
Metabolite Identification
Common Name(9E,11E)-Octadecadienoic acid
DescriptionConjugated linoleic acid is an integral term for the mixture of positional and geometrical isomers of the octadecadienoic acids, whose two double-bonds are separated with one single-bond. The most common isomers are cis-9, trans-11, and trans-10, cis-12. Conjugated linoleic acid is present in the food namely in the red meat and dairy products which the contemporary dietary recommendations tend to limit. Those limitations should be compensated with dietary supplements. Much attention has focused on the therapeutic potential of conjugated linoleic acid. Initial animal studies associated conjugated linoleic acid with beneficial health properties, such as reducing the risk of cancer, diabetes, atherosclerosis, inflammation and obesity. More recent human conjugated linoleic acid supplementation studies have often shown conflicting and less convincing health benefits. The marked variation between studies may reflect the isomer-specific effect of the individual conjugated linoleic acid isomers, which can often have opposing effects. Detrimental effects have been observed in some studies, in particular after supplementation with the trans-10,cis-12 conjugated linoleic acid isomer. Diet composition may modulate CLA effects on body fat accumulation. As far as human studies are concerned, a specific dietary pattern has not been established. As a result differences among studies and also among subjects in the same study are likely. In rodents, the effects of CLA vary with genotype, suggesting that genetic predisposition to fat accumulation can play an important role in the effectiveness of CLA. Human volunteers with different body mass index have participated in the published studies and even in the same experiment. So, differences in lipid metabolism among subjects could help to explain the discrepancies observed in the literature. Age and maturity may also be crucial. (PMID: 17053429 , 17217167 , 17554969 , 16477173 ).
9,11-Linoleic acidHMDB, MeSH
Conjugated linoleic acidHMDB
Nouracid de 554HMDB
Ricineic acidHMDB
Ricinenic acidHMDB
Selin claHMDB
9,11-Linoleic acid, (E,E)-isomerMeSH, HMDB
9,11-Isolinoleic acidMeSH, HMDB
Octadeca-9,11-dienoic acidMeSH, HMDB
9,11-OctadecadienoateMeSH, HMDB
(9E,11E)-9,11-Octadecadienoic acidHMDB, ChEBI
(9E,11E)-Octadecadienoic acidHMDB
9,11-Conjugated linoleic acidHMDB
9-trans,11-trans-Linoleic acidHMDB
9-trans,11-trans-Octadecadienoic acidHMDB, ChEBI
9E,11E-Octadecadienoic acidHMDB
delta9,11-Octadecadienoic acidHMDB
trans-11-trans-9-Octadecadienoic acidHMDB
trans-9,trans-11 Conjugated linoleic acidHMDB
trans-9,trans-11-Octadecadienoic acidHMDB
Δ9,11-Octadecadienoic acidHMDB
(E,E)-9,11-Octadecadienoic acidChEBI
(E,E)-Isolinoleic acidChEBI
9-trans, 11-trans-CLAChEBI
9-trans,11-trans-Conjugated linoleic acidChEBI
Conjugated (9E,11E)-linoleic acidChEBI
Isolinoleic acidChEBI
Mangold's acidChEBI
trans,trans-9,11-Octadecadienoic acidChEBI
trans-9, trans-11-Octadecadienoic acidChEBI
9-trans,11-trans-Conjugated linoleateGenerator
Conjugated (9E,11E)-linoleateGenerator
trans-9, trans-11-OctadecadienoateGenerator
Chemical FormulaC18H32O2
Average Molecular Weight280.4455
Monoisotopic Molecular Weight280.240230268
IUPAC Name(9E,11E)-octadeca-9,11-dienoic acid
Traditional Name9E,11E-octadecadienoic acid
CAS Registry Number1839-11-8
InChI Identifier
Chemical Taxonomy
Description belongs to the class of organic compounds known as lineolic acids and derivatives. These are derivatives of lineolic acid. Lineolic acid is a polyunsaturated omega-6 18 carbon long fatty acid, with two CC double bonds at the 9- and 12-positions.
KingdomOrganic compounds
Super ClassLipids and lipid-like molecules
ClassFatty Acyls
Sub ClassLineolic acids and derivatives
Direct ParentLineolic acids and derivatives
Alternative Parents
  • Octadecanoid
  • Long-chain fatty acid
  • Fatty acid
  • Unsaturated fatty acid
  • Straight chain fatty acid
  • Monocarboxylic acid or derivatives
  • Carboxylic acid
  • Carboxylic acid derivative
  • Organic oxygen compound
  • Organic oxide
  • Hydrocarbon derivative
  • Organooxygen compound
  • Carbonyl group
  • Aliphatic acyclic compound
Molecular FrameworkAliphatic acyclic compounds
External Descriptors
Physiological effect

Health effect:


Route of exposure:


Biological location:


Naturally occurring process:


Industrial application:

Biological role:

Physical Properties
Experimental Properties
Melting PointNot AvailableNot Available
Boiling PointNot AvailableNot Available
Water SolubilityNot AvailableNot Available
LogPNot AvailableNot Available
Predicted Properties
Water Solubility0.00015 g/LALOGPS
pKa (Strongest Acidic)4.99ChemAxon
Physiological Charge-1ChemAxon
Hydrogen Acceptor Count2ChemAxon
Hydrogen Donor Count1ChemAxon
Polar Surface Area37.3 ŲChemAxon
Rotatable Bond Count14ChemAxon
Refractivity88.52 m³·mol⁻¹ChemAxon
Polarizability37.12 ųChemAxon
Number of Rings0ChemAxon
Rule of FiveNoChemAxon
Ghose FilterNoChemAxon
Veber's RuleNoChemAxon
MDDR-like RuleNoChemAxon
Spectrum TypeDescriptionSplash KeyView
Predicted GC-MSPredicted GC-MS Spectrum - GC-MS (Non-derivatized) - 70eV, Positivesplash10-052f-9550000000-f91f775c11691e572339Spectrum
Predicted GC-MSPredicted GC-MS Spectrum - GC-MS (1 TMS) - 70eV, Positivesplash10-0079-9531000000-ff0f0a6283e777000b03Spectrum
LC-MS/MSLC-MS/MS Spectrum - ESI-TOF 20V, Negativesplash10-004i-0090000000-d3517fc9c425686f3f47Spectrum
LC-MS/MSLC-MS/MS Spectrum - ESI-TOF 10V, Negativesplash10-004i-0090000000-dfad2b4819a8e09aeb74Spectrum
LC-MS/MSLC-MS/MS Spectrum - ESI-TOF 10V, Negativesplash10-004i-0093020000-3713e3e16e9fc8ff9d4eSpectrum
LC-MS/MSLC-MS/MS Spectrum - ESI-TOF 30V, Negativesplash10-004i-0090000000-1ab95baf25a47f7edbbeSpectrum
LC-MS/MSLC-MS/MS Spectrum - ESI-TOF , Negativesplash10-004i-0091000000-88b67552039f5c14c7eaSpectrum
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-TOF , negativesplash10-004i-0090000000-d3517fc9c425686f3f47Spectrum
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-TOF , negativesplash10-004i-0090000000-dfad2b4819a8e09aeb74Spectrum
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-TOF , negativesplash10-004i-0090000000-1ab95baf25a47f7edbbeSpectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Positivesplash10-03di-0090000000-f2c6c9de24118516f0dbSpectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Positivesplash10-022j-5690000000-f4c090f44fe34f660b19Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Positivesplash10-006x-9830000000-42ee75da80e6ee682b90Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Negativesplash10-004i-0090000000-f1e9e4b543f7d4f48bf8Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Negativesplash10-01ti-0090000000-665523c6142ff4e39c96Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Negativesplash10-0a4l-9230000000-b43315d97b9995f922a3Spectrum
Biological Properties
Cellular Locations
  • Extracellular
  • Membrane (predicted from logP)
Biospecimen Locations
  • Blood
Tissue LocationsNot Available
Normal Concentrations
BloodDetected and Quantified19.3 +/- 3.9 uMAdult (>18 years old)BothNormal details
Abnormal Concentrations
BloodDetected and Quantified25.3 +/- 1.1 uMAdult (>18 years old)Both
Lipid peroxidation
BloodDetected and Quantified24.0 +/- 11.0 uMAdult (>18 years old)BothPrimary biliary Cirrhosis details
Associated Disorders and Diseases
Disease References
Lipid peroxidation
  1. Thompson S, Smith MT: Measurement of the diene conjugated form of linoleic acid in plasma by high performance liquid chromatography: a questionable non-invasive assay of free radical activity? Chem Biol Interact. 1985 Nov;55(3):357-66. [PubMed:4075442 ]
Primary biliary cirrhosis
  1. Braganza JM, Day JP: Serum octadeca-9-11 dienoic acid concentrations in primary biliary cirrhosis. Lancet. 1987 Apr 25;1(8539):987. [PubMed:2882386 ]
Associated OMIM IDs
DrugBank IDNot Available
Phenol Explorer Compound IDNot Available
FooDB IDFDB023610
KNApSAcK IDNot Available
Chemspider ID4445923
KEGG Compound IDNot Available
BioCyc IDNot Available
BiGG IDNot Available
Wikipedia LinkNot Available
METLIN IDNot Available
PubChem Compound5282796
PDB IDNot Available
ChEBI ID36025
Food Biomarker OntologyNot Available
VMH IDNot Available
MarkerDB ID
Synthesis ReferencePriester, Remmet. 9,11-Octadecadienoic acid. (1939), US 2156737 19390502 CAN 33:44507 AN 1939:44507
Material Safety Data Sheet (MSDS)Not Available
General References
  1. Toomey S, McMonagle J, Roche HM: Conjugated linoleic acid: a functional nutrient in the different pathophysiological components of the metabolic syndrome? Curr Opin Clin Nutr Metab Care. 2006 Nov;9(6):740-7. [PubMed:17053429 ]
  2. Navarro V, Fernandez-Quintela A, Churruca I, Portillo MP: The body fat-lowering effect of conjugated linoleic acid: a comparison between animal and human studies. J Physiol Biochem. 2006 Jun;62(2):137-47. [PubMed:17217167 ]
  3. Tvrzicka E, Vecka M, Zak A: [Conjugated linoleic acid--the dietary supplement in the prevention of cardiovascular diseases]. Cas Lek Cesk. 2007;146(5):459-65. [PubMed:17554969 ]
  4. Tricon S, Yaqoob P: Conjugated linoleic acid and human health: a critical evaluation of the evidence. Curr Opin Clin Nutr Metab Care. 2006 Mar;9(2):105-10. [PubMed:16477173 ]