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Record Information
Creation Date2005-11-16 15:48:42 UTC
Update Date2016-02-11 01:02:12 UTC
Secondary Accession Numbers
  • HMDB00456
  • HMDB00515
Metabolite Identification
Common NameL-Acetylcarnitine
DescriptionL-Acetylcarnitine is an acetic acid ester of carnitine that facilitates movement of acetyl CoA into the matrices of mammalian mitochondria during the oxidation of fatty acids. In addition to his metabolic role, acetyl-L-carnitine (ALC) posses unique neuroprotective, neuromodulatory, and neurotrophic properties this may play an important role in counteracting various disease processes. (PubMed ID 15363640).
3-(Acetyloxy)-4-(trimethylammonio)butanoic acidGenerator
L-Carnitine acetyl esterHMDB
Levocarnitine acetylHMDB
Chemical FormulaC9H17NO4
Average Molecular Weight203.2356
Monoisotopic Molecular Weight203.115758037
IUPAC Name3-(acetyloxy)-4-(trimethylazaniumyl)butanoate
Traditional Namealcar
CAS Registry Number3040-38-8
InChI Identifier
Chemical Taxonomy
DescriptionThis compound 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
  • Carnitine
  • Acyl choline
  • Choline
  • Dicarboxylic acid or derivatives
  • Acetate salt
  • Quaternary ammonium salt
  • Carboxylic acid salt
  • Carboxylic acid ester
  • Carboxylic acid
  • Carboxylic acid derivative
  • Hydrocarbon derivative
  • Organic salt
  • Organooxygen compound
  • Organonitrogen compound
  • Carbonyl group
  • Amine
  • Organic zwitterion
  • Aliphatic acyclic compound
Molecular FrameworkAliphatic acyclic compounds
External Descriptors
StatusDetected and Quantified
  • Endogenous
  • Food
  • Cell signaling
  • Component of Alanine and aspartate metabolism
  • Fuel and energy storage
  • Fuel or energy source
  • Membrane integrity/stability
  • Nutrients
  • Stabilizers
  • Surfactants and Emulsifiers
Cellular locations
  • Cytoplasm
  • Extracellular
  • Membrane
  • Mitochondria
  • Endoplasmic reticulum
  • Peroxisome
Physical Properties
Experimental Properties
Melting Point145 °CNot Available
Boiling PointNot AvailableNot Available
Water SolubilityNot AvailableNot Available
LogPNot AvailableNot Available
Predicted Properties
Water Solubility0.35 mg/mLALOGPS
pKa (Strongest Acidic)4.09ChemAxon
pKa (Strongest Basic)-7ChemAxon
Physiological Charge0ChemAxon
Hydrogen Acceptor Count3ChemAxon
Hydrogen Donor Count0ChemAxon
Polar Surface Area66.43 Å2ChemAxon
Rotatable Bond Count6ChemAxon
Refractivity72.64 m3·mol-1ChemAxon
Polarizability20.87 Å3ChemAxon
Number of Rings0ChemAxon
Rule of FiveYesChemAxon
Ghose FilterYesChemAxon
Veber's RuleYesChemAxon
MDDR-like RuleYesChemAxon
Spectrum TypeDescriptionSplash Key
GC-MSGC-MS Spectrum - GC-MSNot Available
LC-MS/MSLC-MS/MS Spectrum - Quattro_QQQ 10V, N/A (Annotated)splash10-000i-9200000000-e3a84538f1dadc72bc00View in MoNA
LC-MS/MSLC-MS/MS Spectrum - Quattro_QQQ 25V, N/A (Annotated)splash10-000i-9000000000-5d5d6858632925cf1c81View in MoNA
LC-MS/MSLC-MS/MS Spectrum - Quattro_QQQ 40V, N/A (Annotated)splash10-001i-9000000000-b7dbd311ea9af892ad91View in MoNA
1D NMR1H NMR SpectrumNot Available
1D NMR1H NMR SpectrumNot Available
1D NMR13C NMR SpectrumNot Available
2D NMR[1H,13C] 2D NMR SpectrumNot Available
Biological Properties
Cellular Locations
  • Cytoplasm
  • Extracellular
  • Membrane
  • Mitochondria
  • Endoplasmic reticulum
  • Peroxisome
Biofluid Locations
  • Blood
  • Breast Milk
  • Cerebrospinal Fluid (CSF)
  • Saliva
  • Urine
Tissue Location
  • Brain
  • Muscle
  • Nerve Cells
  • Neuron
  • Prostate
  • Skeletal Muscle
  • Spermatozoa
Adrenoleukodystrophy, X-linkedSMP00516Not Available
Beta Oxidation of Very Long Chain Fatty AcidsSMP00052map01040
Carnitine-acylcarnitine translocase deficiencySMP00517Not Available
Oxidation of Branched Chain Fatty AcidsSMP00030Not Available
Normal Concentrations
BloodDetected and Quantified5.48 +/- 2.15 uMAdult (>18 years old)BothNormal details
BloodDetected and Quantified6.2 +/- 0.6 uMAdult (>18 years old)MaleNormal details
BloodDetected and Quantified5.7 +/- 0.7 uMAdult (>18 years old)FemaleNormal details
BloodDetected and Quantified4.90 (2.48-8.62) uMChildren (1-13 years old)BothNormal details
Breast MilkDetected and Quantified10.5 +/- 4.7 uMAdult (>18 years old)Female
Cerebrospinal Fluid (CSF)Detected and Quantified0.322 +/- 0.148 uMAdult (>18 years old)Not SpecifiedNormal details
SalivaDetected and Quantified0.973 +/- 0.002 uMAdult (>18 years old)BothNormal
    • Zerihun T. Dame, ...
SalivaDetected and Quantified0.843 +/- 0.441 uMAdult (>18 years old)Male
    • Sugimoto et al. (...
SalivaDetected and Quantified0.955 +/- 0.442 uMAdult (>18 years old)Female
    • Sugimoto et al. (...
SalivaDetected and Quantified1.53 +/- 1.23 uMAdult (>18 years old)Female
    • Sugimoto et al. (...
SalivaDetected and Quantified1.68 +/- 0.780 uMAdult (>18 years old)Female
    • Sugimoto et al. (...
SalivaDetected but not QuantifiedNot ApplicableAdult (>18 years old)Not SpecifiedNormal details
UrineDetected but not QuantifiedNot ApplicableAdult (>18 years old)MaleNormal details
UrineDetected but not QuantifiedNot ApplicableAdult (>18 years old)BothNormal details
UrineDetected and Quantified4.468 +/- 3.521 umol/mmol creatinineChildren (1 - 13 years old)Not Specified
    • Mordechai, Hien, ...
UrineDetected and Quantified2.0 (0.4-5.9) umol/mmol creatinineAdult (>18 years old)Both
UrineDetected and Quantified2.8 (0.6-7.5) umol/mmol creatinineAdult (>18 years old)Both
UrineDetected and Quantified7.2058 +/- 6.0635 umol/mmol creatinineChildren (1 - 13 years old)Not Specified
    • Mordechai, Hien, ...
UrineDetected and Quantified1.928 +/- 0.2829 umol/mmol creatinineAdult (>18 years old)FemaleNormal details
Abnormal Concentrations
BloodDetected but not QuantifiedNot ApplicableAdult (>18 years old)BothColorectal cancer details
BloodDetected and Quantified0.316 (0.091-0.760) uMAdult (>18 years old)BothVery long-chain acyl-CoA dehydrogenase deficiency (vLCAD) details
UrineDetected but not QuantifiedNot ApplicableAdult (>18 years old)Both
Bladder cancer
UrineDetected and Quantified9.443 +/- 12.772 umol/mmol creatinineChildren (1 - 13 years old)Not Specified
Eosinophilic esophagitis
    • Mordechai, Hien, ...
UrineDetected and Quantified6.5552 +/- 13.7484 umol/mmol creatinineChildren (1 - 13 years old)Not Specified
Eosinophilic esophagitis
    • Mordechai, Hien, ...
UrineDetected but not QuantifiedNot ApplicableAdult (>18 years old)BothColorectal cancer details
UrineDetected and Quantified6.3512 +/- 10.4433 umol/mmol creatinineChildren (1 - 13 years old)Not Specified
Gastroesophageal reflux disease
    • Mordechai, Hien, ...
Associated Disorders and Diseases
Disease References
Very Long Chain Acyl-CoA Dehydrogenase Deficiency
  1. Costa CG, Struys EA, Bootsma A, ten Brink HJ, Dorland L, Tavares de Almeida I, Duran M, Jakobs C: Quantitative analysis of plasma acylcarnitines using gas chromatography chemical ionization mass fragmentography. J Lipid Res. 1997 Jan;38(1):173-82. [9034211 ]
Associated OMIM IDsNone
DrugBank IDNot Available
DrugBank Metabolite IDNot Available
Phenol Explorer Compound IDNot Available
Phenol Explorer Metabolite IDNot Available
FoodDB IDFDB021904
KNApSAcK IDNot Available
Chemspider ID21243783
KEGG Compound IDC02571
BioCyc ID(-)o-acetylcarnitine
BiGG ID1442845
Wikipedia LinkAcetyl-L-carnitine
NuGOwiki LinkHMDB00201
Metagene LinkHMDB00201
PubChem Compound1
PDB IDNot Available
ChEBI IDNot Available
Synthesis ReferenceGu, Heng-da; Shi, Shuang; Yang, Ying; Shi, Zhao-xin; Yu, Zhan-long. Synthesis of acetyl-L-carnitine by direct acylation method. Shenyang Huagong Xueyuan Xuebao (2006), 20(2), 154-155, 160.
Material Safety Data Sheet (MSDS)Not Available
General References
  1. Sreekumar A, Poisson LM, Rajendiran TM, Khan AP, Cao Q, Yu J, Laxman B, Mehra R, Lonigro RJ, Li Y, Nyati MK, Ahsan A, Kalyana-Sundaram S, Han B, Cao X, Byun J, Omenn GS, Ghosh D, Pennathur S, Alexander DC, Berger A, Shuster JR, Wei JT, Varambally S, Beecher C, Chinnaiyan AM: Metabolomic profiles delineate potential role for sarcosine in prostate cancer progression. Nature. 2009 Feb 12;457(7231):910-4. [19212411 ]
  2. Sakuma T: Alteration of urinary carnitine profile induced by benzoate administration. Arch Dis Child. 1991 Jul;66(7):873-5. [1863104 ]
  3. Grizard G, Lombard-Vignon N, Boucher D: Changes in carnitine and acetylcarnitine in human semen during cryopreservation. Hum Reprod. 1992 Oct;7(9):1245-8. [1479006 ]
  4. Kamimori H, Hamashima Y, Konishi M: Determination of carnitine and saturated-acyl group carnitines in human urine by high-performance liquid chromatography with fluorescence detection. Anal Biochem. 1994 May 1;218(2):417-24. [8074302 ]
  5. Cooper MB, Forte CA, Jones DA: Citrate interference with the determination of acetylcarnitine: a method for its elimination. Clin Chim Acta. 1986 Sep 30;159(3):291-9. [3769216 ]
  6. Spagnoli A, Lucca U, Menasce G, Bandera L, Cizza G, Forloni G, Tettamanti M, Frattura L, Tiraboschi P, Comelli M, et al.: Long-term acetyl-L-carnitine treatment in Alzheimer's disease. Neurology. 1991 Nov;41(11):1726-32. [1944900 ]
  7. Brooks DE: Carnitine, acetylcarnitine and the activity of carnitine acyltransferases in seminal plasma and spermatozoa of men, rams and rats. J Reprod Fertil. 1979 Jul;56(2):667-73. [480318 ]
  8. Inoue F, Terada N, Nakajima H, Okochi M, Kodo N, Kizaki Z, Kinugasa A, Sawada T: Effect of sports activity on carnitine metabolism. Measurement of free carnitine, gamma-butyrobetaine and acylcarnitines by tandem mass spectrometry. J Chromatogr B Biomed Sci Appl. 1999 Aug 6;731(1):83-8. [10491992 ]
  9. Niu YJ, Jiang ZM, Shu H, Li CF, Liu W, Yao GX, Jiang J, Li JQ, Longo A: [Assay of carnitine in plasma and urine of healthy adults] Zhongguo Yi Xue Ke Xue Yuan Xue Bao. 2002 Apr;24(2):185-7. [12905800 ]
  10. Siliprandi N, Di Lisa F, Pieralisi G, Ripari P, Maccari F, Menabo R, Giamberardino MA, Vecchiet L: Metabolic changes induced by maximal exercise in human subjects following L-carnitine administration. Biochim Biophys Acta. 1990 Apr 23;1034(1):17-21. [2328258 ]
  11. Marzo A, Cardace G, Corbelleta C, Bassani E, Morabito E, Arrigoni Martelli E: Homeostatic equilibrium of L-carnitine family before and after i.v. administration of propionyl-L-carnitine in humans, dogs and rats. Eur J Drug Metab Pharmacokinet. 1991;Spec No 3:357-63. [1820908 ]
  12. Novak M, Wieser PB, Buch M, Hahn P: Acetylcarnitine and free carnitine in body fluids before and after birth. Pediatr Res. 1979 Jan;13(1):10-5. [571081 ]
  13. Battistin L, Pizzolato G, Dam M, Da Col C, Perlotto N, Saitta B, Borsato N, Calvani M, Ferlin G: Single-photon emission computed tomography studies with 99mTc-hexamethylpropyleneamine oxime in dementia: effects of acute administration of L-acetylcarnitine. Eur Neurol. 1989;29(5):261-5. [2792144 ]
  14. Deufel T: Determination of L-carnitine in biological fluids and tissues. J Clin Chem Clin Biochem. 1990 May;28(5):307-11. [2380667 ]
  15. Minkler PE, Hoppel CL: Quantification of free carnitine, individual short- and medium-chain acylcarnitines, and total carnitine in plasma by high-performance liquid chromatography. Anal Biochem. 1993 Aug 1;212(2):510-8. [8214594 ]
  16. Bruno G, Scaccianoce S, Bonamini M, Patacchioli FR, Cesarino F, Grassini P, Sorrentino E, Angelucci L, Lenzi GL: Acetyl-L-carnitine in Alzheimer disease: a short-term study on CSF neurotransmitters and neuropeptides. Alzheimer Dis Assoc Disord. 1995 Fall;9(3):128-31. [8534410 ]
  17. Pace S, Longo A, Toon S, Rolan P, Evans AM: Pharmacokinetics of propionyl-L-carnitine in humans: evidence for saturable tubular reabsorption. Br J Clin Pharmacol. 2000 Nov;50(5):441-8. [11069438 ]
  18. De Rosa M, Boggia B, Amalfi B, Zarrilli S, Vita A, Colao A, Lombardi G: Correlation between seminal carnitine and functional spermatozoal characteristics in men with semen dysfunction of various origins. Drugs R D. 2005;6(1):1-9. [15801863 ]
  19. Zanelli SA, Solenski NJ, Rosenthal RE, Fiskum G: Mechanisms of ischemic neuroprotection by acetyl-L-carnitine. Ann N Y Acad Sci. 2005 Aug;1053:153-61. [16179519 ]
  20. Kuratsune H, Yamaguti K, Lindh G, Evengard B, Hagberg G, Matsumura K, Iwase M, Onoe H, Takahashi M, Machii T, Kanakura Y, Kitani T, Langstrom B, Watanabe Y: Brain regions involved in fatigue sensation: reduced acetylcarnitine uptake into the brain. Neuroimage. 2002 Nov;17(3):1256-65. [12414265 ]
  21. Gray SC, Devito G, Nimmo MA: Effect of active warm-up on metabolism prior to and during intense dynamic exercise. Med Sci Sports Exerc. 2002 Dec;34(12):2091-6. [12471321 ]


General function:
Involved in acyltransferase activity
Specific function:
Carnitine acetylase is specific for short chain fatty acids. Carnitine acetylase seems to affect the flux through the pyruvate dehydrogenase complex. It may be involved as well in the transport of acetyl-CoA into mitochondria.
Gene Name:
Uniprot ID:
Molecular weight:
Acetyl-CoA + L-Carnitine → Coenzyme A + L-Acetylcarnitinedetails
General function:
Involved in transporter activity
Specific function:
Mediates the transport of acylcarnitines of different length across the mitochondrial inner membrane from the cytosol to the mitochondrial matrix for their oxidation by the mitochondrial fatty acid-oxidation pathway.
Gene Name:
Uniprot ID:
Molecular weight: