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Record Information
StatusDetected and Quantified
Creation Date2017-08-01 02:17:33 UTC
Update Date2021-04-12 19:32:27 UTC
Secondary Accession Numbers
  • HMDB94687
Metabolite Identification
Common NameOctadecenoylcarnitine
DescriptionOctadecenoylcarnitine is an acylcarnitine. More specifically, it is an octadecenoic acic ester of carnitine. Acylcarnitines were first discovered more than 70 year ago (PMID: 13825279 ). It is believed that there are more than 1000 types of acylcarnitines in the human body. The general role of acylcarnitines is to transport acyl-groups (organic acids and fatty acids) from the cytoplasm into the mitochondria so that they can be broken down to produce energy.  This process is known as beta-oxidation. According to a recent review [Dambrova et al. 2021, Physiological Reviews], acylcarnitines (ACs) can be classified into 9 different categories depending on the type and size of their acyl-group: 1) short-chain ACs; 2) medium-chain ACs; 3) long-chain ACs; 4) very long-chain ACs; 5) hydroxy ACs; 6) branched chain ACs; 7) unsaturated ACs; 8) dicarboxylic ACs and 9) miscellaneous ACs. Short-chain ACs have acyl-groups with two to five carbons (C2-C5), medium-chain ACs have acyl-groups with six to thirteen carbons (C6-C13), long-chain ACs have acyl-groups with fourteen to twenty once carbons (C14-C21) and very long-chain ACs have acyl groups with more than 22 carbons. Octadecenoylcarnitine is therefore classified as a long chain AC. As a long-chain acylcarnitine octadecenoylcarnitine is generally formed through esterification with long-chain fatty acids obtained from the diet. The main function of most long-chain acylcarnitines is to ensure long chain fatty acid transport into the mitochondria (PMID: 22804748 ). Altered levels of long-chain acylcarnitines can serve as useful markers for inherited disorders of long-chain fatty acid metabolism. In particular octadecenoylcarnitine is elevated in the blood or plasma of individuals with carnitine palmitoyl transferase 2 deficiency (PMID: 15653102 , PMID: 11999976 ), cardiovascular mortality in incident dialysis patients (PMID: 24308938 ), schizophrenia (PMID: 31161852 ), succinic semialdehyde dehydrogenase deficiency (PMID: 32967698 ), neonatal macrosomia (PMID: 32126138 ), liver cirrhosis (PMID: 32075591 ), CPT II deficiency (PMID: 28801073 , PMID: 18987586 , PMID: 18925671 , PMID: 11585077 ), carnitine/acylcarnitine translocase (CACT) deficiency (PMID: 15057979 ), and ischaemia/reperfusion (PMID: 26936967 , PMID: 22607863 , PMID: 24468136 ). Octadecenoylcarnitine is found to be associated with glutaric aciduria II, which is an inborn error of metabolism. Carnitine palmitoyltransferase I (CPT I, EC: is involved in the synthesis of long-chain acylcarnitines (more than C12) on the mitochondrial outer membrane.  Elevated serum/plasma levels of long-chain acylcarnitines are not only markers for incomplete FA oxidation but also are indicators of altered carbohydrate and lipid metabolism. High serum concentrations of long-chain acylcarnitines in the postprandial or fed state are markers of insulin resistance and arise from insulin's inability to inhibit CPT-1-dependent fatty acid metabolism in muscles and the heart (PMID: 19073774 ). Increased intracellular content of long-chain acylcarnitines is thought to serve as a feedback inhibition mechanism of insulin action (PMID: 23258903 ). In healthy subjects, increased concentrations of insulin effectively inhibits long-chain acylcarnitine production. Several studies have also found increased levels of circulating long-chain acylcarnitines in chronic heart failure patients (PMID: 26796394 ). The study of acylcarnitines is an active area of research and it is likely that many novel acylcarnitines will be discovered in the coming years. It is also likely that many novel roles in health and disease will be uncovered. An excellent review of the current state of knowledge for acylcarnitines is available at [Dambrova et al. 2021, Physiological Reviews].
Chemical FormulaC25H47NO4
Average Molecular Weight425.654
Monoisotopic Molecular Weight425.350508997
IUPAC Name3-(octadec-2-enoyloxy)-4-(trimethylazaniumyl)butanoate
Traditional Name3-(octadec-2-enoyloxy)-4-(trimethylammonio)butanoate
CAS Registry NumberNot Available
InChI Identifier
Chemical Taxonomy
Description belongs to the class of organic compounds known as acyl carnitines. These are organic compounds containing a fatty acid with the carboxylic acid attached to carnitine through an ester bond.
KingdomOrganic compounds
Super ClassLipids and lipid-like molecules
ClassFatty Acyls
Sub ClassFatty acid esters
Direct ParentAcyl carnitines
Alternative Parents
  • Acyl-carnitine
  • Dicarboxylic acid or derivatives
  • Tetraalkylammonium salt
  • Alpha,beta-unsaturated carboxylic ester
  • Enoate ester
  • Quaternary ammonium salt
  • Carboxylic acid ester
  • Carboxylic acid salt
  • Carboxylic acid derivative
  • Carboxylic acid
  • Organic nitrogen compound
  • Organooxygen compound
  • Organonitrogen compound
  • Organic salt
  • Hydrocarbon derivative
  • Organic oxide
  • Organopnictogen compound
  • Organic oxygen compound
  • Carbonyl group
  • Amine
  • Aliphatic acyclic compound
Molecular FrameworkAliphatic acyclic compounds
External DescriptorsNot Available

Route of exposure:


Biological location:


Naturally occurring process:


Biological role:

Physical Properties
StateNot Available
Experimental Properties
Melting PointNot AvailableNot Available
Boiling PointNot AvailableNot Available
Water SolubilityNot AvailableNot Available
LogPNot AvailableNot Available
Predicted Properties
pKa (Strongest Acidic)4.17ChemAxon
pKa (Strongest Basic)-6.8ChemAxon
Physiological Charge0ChemAxon
Hydrogen Acceptor Count3ChemAxon
Hydrogen Donor Count0ChemAxon
Polar Surface Area66.43 ŲChemAxon
Rotatable Bond Count21ChemAxon
Refractivity147.37 m³·mol⁻¹ChemAxon
Polarizability53.44 ųChemAxon
Number of Rings0ChemAxon
Rule of FiveYesChemAxon
Ghose FilterNoChemAxon
Veber's RuleNoChemAxon
MDDR-like RuleNoChemAxon
Not Available
Biological Properties
Cellular LocationsNot Available
Biospecimen Locations
  • Blood
  • Feces
Tissue LocationsNot Available
Normal Concentrations
BloodDetected and Quantified<0.28 uMAdolescent (13-18 years old)MaleNormal details
BloodDetected and Quantified0.12 +/- 0.03 uMAdult (>18 years old)BothNormal details
BloodDetected and Quantified0.14(0.04) uMAdult (>18 years old)BothNormal details
FecesDetected and Quantified0.36 +/- 0.3 nmol/g wet fecesAdult (>18 years old)Both
FecesDetected and Quantified0.16 +/- 0.1 nmol/g wet fecesAdult (>18 years old)Both
Abnormal Concentrations
BloodDetected and Quantified1.02 uMAdolescent (13-18 years old)Male
Glutaric aciduria II
BloodDetected and Quantified2.6 uMAdolescent (13-18 years old)MaleGlutaric aciduria II details
BloodDetected and Quantified0.0477 (0.043) uMAdult (>18 years old)FemalePregnancy with fetus having congenital heart defect details
BloodDetected and Quantified0.0835 (0.037) uMAdult (>18 years old)FemalePregnancy details
BloodDetected and Quantified0.2(0.08) uMAdult (>18 years old)BothHeart failure with preserved ejection fraction details
Associated Disorders and Diseases
Disease References
  1. Bahado-Singh RO, Ertl R, Mandal R, Bjorndahl TC, Syngelaki A, Han B, Dong E, Liu PB, Alpay-Savasan Z, Wishart DS, Nicolaides KH: Metabolomic prediction of fetal congenital heart defect in the first trimester. Am J Obstet Gynecol. 2014 Sep;211(3):240.e1-240.e14. doi: 10.1016/j.ajog.2014.03.056. Epub 2014 Apr 1. [PubMed:24704061 ]
Glutaric aciduria II
  1. Prasad M, Hussain S: Glutaric aciduria type II presenting as myopathy and rhabdomyolysis in a teenager. J Child Neurol. 2015 Jan;30(1):96-9. doi: 10.1177/0883073813516676. Epub 2014 Jan 21. [PubMed:24453145 ]
Associated OMIM IDs
DrugBank IDNot Available
Phenol Explorer Compound IDNot Available
FooDB IDNot Available
KNApSAcK IDNot Available
Chemspider IDNot Available
KEGG Compound IDNot Available
BioCyc IDNot Available
BiGG IDNot Available
Wikipedia LinkNot Available
METLIN IDNot Available
PubChem Compound87076413
PDB IDNot Available
ChEBI ID91164
Food Biomarker OntologyNot Available
VMH IDNot Available
MarkerDB IDMDB00029902
Synthesis ReferenceNot Available
Material Safety Data Sheet (MSDS)Not Available
General References
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  2. Watson AD: Thematic review series: systems biology approaches to metabolic and cardiovascular disorders. Lipidomics: a global approach to lipid analysis in biological systems. J Lipid Res. 2006 Oct;47(10):2101-11. Epub 2006 Aug 10. [PubMed:16902246 ]
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  4. Lingwood D, Simons K: Lipid rafts as a membrane-organizing principle. Science. 2010 Jan 1;327(5961):46-50. doi: 10.1126/science.1174621. [PubMed:20044567 ]
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  7. Minkler PE, Kerner J, North KN, Hoppel CL: Quantitation of long-chain acylcarnitines by HPLC/fluorescence detection: application to plasma and tissue specimens from patients with carnitine palmitoyltransferase-II deficiency. Clin Chim Acta. 2005 Feb;352(1-2):81-92. [PubMed:15653102 ]
  8. Gempel K, Kiechl S, Hofmann S, Lochmuller H, Kiechl-Kohlendorfer U, Willeit J, Sperl W, Rettinger A, Bieger I, Pongratz D, Gerbitz KD, Bauer MF: Screening for carnitine palmitoyltransferase II deficiency by tandem mass spectrometry. J Inherit Metab Dis. 2002 Feb;25(1):17-27. [PubMed:11999976 ]
  9. Kalim S, Clish CB, Wenger J, Elmariah S, Yeh RW, Deferio JJ, Pierce K, Deik A, Gerszten RE, Thadhani R, Rhee EP: A plasma long-chain acylcarnitine predicts cardiovascular mortality in incident dialysis patients. J Am Heart Assoc. 2013 Dec 5;2(6):e000542. doi: 10.1161/JAHA.113.000542. [PubMed:24308938 ]
  10. Cao B, Wang D, Pan Z, McIntyre RS, Brietzke E, Subramanieapillai M, Nozari Y, Wang J: Metabolic profiling for water-soluble metabolites in patients with schizophrenia and healthy controls in a Chinese population: A case-control study. World J Biol Psychiatry. 2020 Jun;21(5):357-367. doi: 10.1080/15622975.2019.1615639. Epub 2019 Jun 4. [PubMed:31161852 ]
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  14. Tajima G, Hara K, Tsumura M, Kagawa R, Okada S, Sakura N, Maruyama S, Noguchi A, Awaya T, Ishige M, Ishige N, Musha I, Ajihara S, Ohtake A, Naito E, Hamada Y, Kono T, Asada T, Sasai H, Fukao T, Fujiki R, Ohara O, Bo R, Yamada K, Kobayashi H, Hasegawa Y, Yamaguchi S, Takayanagi M, Hata I, Shigematsu Y, Kobayashi M: Newborn screening for carnitine palmitoyltransferase II deficiency using (C16+C18:1)/C2: Evaluation of additional indices for adequate sensitivity and lower false-positivity. Mol Genet Metab. 2017 Nov;122(3):67-75. doi: 10.1016/j.ymgme.2017.07.011. Epub 2017 Jul 31. [PubMed:28801073 ]
  15. Brucknerova I, Bzduch V, Behulova D, Ferianec V, Dubovicky M, Ujhazy E, Mach M: Reversible asphyxial status in a newborn due to neonatal form of carnitine palmitoyltransferase II deficiency. Neuro Endocrinol Lett. 2008 Oct;29(5):627-30. [PubMed:18987586 ]
  16. Illsinger S, Lucke T, Peter M, Ruiter JP, Wanders RJ, Deschauer M, Handig I, Wuyts W, Das AM: Carnitine-palmitoyltransferase 2 deficiency: novel mutations and relevance of newborn screening. Am J Med Genet A. 2008 Nov 15;146A(22):2925-8. doi: 10.1002/ajmg.a.32545. [PubMed:18925671 ]
  17. Gempel K, von Praun C, Baumkotter J, Lehnert W, Ensenauer R, Gerbitz KD, Bauer MF: "Adult" form of muscular carnitine palmitoyltransferase II deficiency: manifestation in a 2-year-old child. Eur J Pediatr. 2001 Sep;160(9):548-51. doi: 10.1007/s004310100802. [PubMed:11585077 ]
  18. Iacobazzi V, Pasquali M, Singh R, Matern D, Rinaldo P, Amat di San Filippo C, Palmieri F, Longo N: Response to therapy in carnitine/acylcarnitine translocase (CACT) deficiency due to a novel missense mutation. Am J Med Genet A. 2004 Apr 15;126A(2):150-5. [PubMed:15057979 ]
  19. Liepinsh E, Makrecka-Kuka M, Volska K, Kuka J, Makarova E, Antone U, Sevostjanovs E, Vilskersts R, Strods A, Tars K, Dambrova M: Long-chain acylcarnitines determine ischaemia/reperfusion-induced damage in heart mitochondria. Biochem J. 2016 May 1;473(9):1191-202. doi: 10.1042/BCJ20160164. Epub 2016 Mar 2. [PubMed:26936967 ]
  20. Shah SH, Sun JL, Stevens RD, Bain JR, Muehlbauer MJ, Pieper KS, Haynes C, Hauser ER, Kraus WE, Granger CB, Newgard CB, Califf RM, Newby LK: Baseline metabolomic profiles predict cardiovascular events in patients at risk for coronary artery disease. Am Heart J. 2012 May;163(5):844-850.e1. doi: 10.1016/j.ahj.2012.02.005. [PubMed:22607863 ]
  21. Rizza S, Copetti M, Rossi C, Cianfarani MA, Zucchelli M, Luzi A, Pecchioli C, Porzio O, Di Cola G, Urbani A, Pellegrini F, Federici M: Metabolomics signature improves the prediction of cardiovascular events in elderly subjects. Atherosclerosis. 2014 Feb;232(2):260-4. doi: 10.1016/j.atherosclerosis.2013.10.029. Epub 2013 Nov 18. [PubMed:24468136 ]
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