ContaminantDB: L-Carnitine

Identification Taxonomy Biological Properties Physical Properties Toxicity Profile Spectra Concentrations Links References Targets (13)XML

Record Information

Version

1.0

Creation Date

2009-07-21 20:27:12 UTC

Update Date

2026-05-14 16:43:03 UTC

Accession Number

CHEM002225

Identification

Common Name

L-Carnitine

Class

Small Molecule

Description

Carnitine is not an essential amino acid; it can be synthesized in the body. However, it is so important in providing energy to muscles including the heart-that some researchers are now recommending carnitine supplements in the diet, particularly for people who do not consume much red meat, the main food source for carnitine. Carnitine has been described as a vitamin, an amino acid, or a metabimin, i.e., an essential metabolite. Like the B vitamins, carnitine contains nitrogen and is very soluble in water, and to some researchers carnitine is a vitamin (Liebovitz 1984). It was found that an animal (yellow mealworm) could not grow without carnitine in its diet. However, as it turned out, almost all other animals, including humans, do make their own carnitine; thus, it is no longer considered a vitamin. Nevertheless, in certain circumstances-such as deficiencies of methionine, lysine or vitamin C or kidney dialysis--carnitine shortages develop. Under these conditions, carnitine must be absorbed from food, and for this reason it is sometimes referred to as a metabimin or a conditionally essential metabolite. Like the other amino acids used or manufactured by the body, carnitine is an amine. But like choline, which is sometimes considered to be a B vitamin, carnitine is also an alcohol (specifically, a trimethylated carboxy-alcohol). Thus, carnitine is an unusual amino acid and has different functions than most other amino acids, which are most usually employed by the body in the construction of protein. Carnitine is an essential factor in fatty acid metabolism in mammals. It's most important known metabolic function is to transport fat into the mitochondria of muscle cells, including those in the heart, for oxidation. This is how the heart gets most of its energy. In humans, about 25% of carnitine is synthesized in the liver, kidney and brain from the amino acids lysine and methionine. Most of the carnitine in the body comes from dietary sources such as red meat and dairy products. Inborn errors of carnitine metabolism can lead to brain deterioration like that of Reye's syndrome, gradually worsening muscle weakness, Duchenne-like muscular dystrophy and extreme muscle weakness with fat accumulation in muscles. Borurn et al. (1979) describe carnitine as an essential nutrient for pre-term babies, certain types (non-ketotic) of hypoglycemics, kidney dialysis patients, cirrhosis, and in kwashiorkor, type IV hyperlipidemia, heart muscle disease (cardiomyopathy), and propionic or organic aciduria (acid urine resulting from genetic or other anomalies). In all these conditions and the inborn errors of carnitine metabolism, carnitine is essential to life and carnitine supplements are valuable. carnitine therapy may also be useful in a wide variety of clinical conditions. carnitine supplementation has improved some patients who have angina secondary to coronary artery disease. It may be worth a trial in any form of hyperlipidemia or muscle weakness. carnitine supplements may be useful in many forms of toxic or metabolic liver disease and in cases of heart muscle disease. Hearts undergoing severe arrhythmia quickly deplete their stores of carnitine. Athletes, particularly in Europe, have used carnitine supplements for improved endurance. carnitine may improve muscle building by improving fat utilization and may even be useful in treating obesity. carnitine joins a long list of nutrients which may be of value in treating pregnant women, hypothyroid individuals, and male infertility due to low motility of sperm. Even the Physician's Desk Reference gives indication for carnitine supplements as improving the tolerance of ischemic heart disease, myocardial insufficiencies, and type IV hyperlipoproteinemia. carnitine deficiency is noted in abnormal liver function, renal dialysis patients, and severe to moderate muscular weakness with associated anorexia.

Contaminant Sources

Cosmetic Chemicals
EAFUS Chemicals
FooDB Chemicals
HMDB Contaminants - Urine
STOFF IDENT Compounds
T3DB toxins

Contaminant Type

Dietary Supplement
Drug
Food Toxin
Human Neurotoxin
Metabolite
Natural Compound
Nootropic Agent
Nutraceutical
Organic Compound
Vitamin B Complex

Chemical Structure

MOL SDF 3D-SDF PDB SMILES InChI View 3D Structure

Synonyms

Value	Source
(-)-Carnitine	ChEBI
(-)-L-Carnitine	ChEBI
3-Carboxy-2-hydroxy-N,N,N-trimethyl-1-propanaminium hydroxide, inner salt	ChEBI
Carnicor	ChEBI
Carnitene	ChEBI
Carnitine	ChEBI
Carnitor	ChEBI
Karnitin	ChEBI
Levocarnitine	ChEBI
Vitamin BT	ChEBI
L-gamma-Trimethyl-beta-hydroxybutyrobetaine	Kegg
(R)-Carnitine	Kegg
L-g-Trimethyl-b-hydroxybutyrobetaine	Generator
L-Γ-trimethyl-β-hydroxybutyrobetaine	Generator
Bicarnesine	MeSH
L Carnitine	MeSH
(-)-(R)-3-Hydroxy-4-(trimethylammonio)butyrate	HMDB
(R)-(3-Carboxy-2-hydroxypropyl)trimethylammonium hydroxide	HMDB
(S)-Carnitine	HMDB
1-Carnitine	HMDB
3-Carboxy-2-hydroxy-N,N,N-trimethyl-1-propanaminium	HMDB
3-Hydroxy-4-trimethylammoniobutanoate	HMDB
3-Hydroxy-4-trimethylammoniobutanoic acid	HMDB
Carniking	HMDB
Carniking 50	HMDB
Carnilean	HMDB
Carnipass	HMDB
Carnipass 20	HMDB
D-Carnitine	HMDB
delta-Carnitine	HMDB
DL-Carnitine	HMDB
gamma-Trimethyl-ammonium-beta-hydroxybutirate	HMDB
gamma-Trimethyl-beta-hydroxybutyrobetaine	HMDB
gamma-Trimethyl-hydroxybutyrobetaine	HMDB
L-(-)-Carnitine	HMDB
Levocarnitina	HMDB
Levocarnitinum	HMDB
R-(-)-3-Hydroxy-4-trimethylaminobutyrate	HMDB
L-Carnitine	ChEBI

Chemical Formula

C₇H₁₅NO₃

Average Molecular Mass

161.199 g/mol

Monoisotopic Mass

161.105 g/mol

CAS Registry Number

541-15-1

IUPAC Name

(3R)-3-hydroxy-4-(trimethylazaniumyl)butanoate

Traditional Name

L-carnitine

SMILES

C[N+](C)(C)C[C@H](O)CC([O-])=O

InChI Identifier

InChI=1S/C7H15NO3/c1-8(2,3)5-6(9)4-7(10)11/h6,9H,4-5H2,1-3H3/t6-/m1/s1

InChI Key

PHIQHXFUZVPYII-ZCFIWIBFSA-N

Chemical Taxonomy

Description

belongs to the class of organic compounds known as carnitines. These are organic compounds containing the quaternary ammonium compound carnitine.

Kingdom

Organic compounds

Super Class

Organic nitrogen compounds

Class

Organonitrogen compounds

Sub Class

Quaternary ammonium salts

Direct Parent

Carnitines

Alternative Parents

Substituents

Carnitine
Beta-hydroxy acid
Short-chain hydroxy acid
Fatty acid
Hydroxy acid
Tetraalkylammonium salt
1,2-aminoalcohol
Carboxylic acid salt
Secondary alcohol
Carboxylic acid derivative
Carboxylic acid
Monocarboxylic acid or derivatives
Organic oxygen compound
Organooxygen compound
Organic zwitterion
Organic salt
Hydrocarbon derivative
Organic oxide
Carbonyl group
Organopnictogen compound
Amine
Alcohol
Aliphatic acyclic compound

Molecular Framework

Aliphatic acyclic compounds

External Descriptors

carnitine (CHEBI:16347 )

Biological Properties

Status

Detected and Not Quantified

Origin

Endogenous

Cellular Locations

Cytoplasm
Endoplasmic reticulum
Extracellular
Membrane
Mitochondria
Peroxisome

Biofluid Locations

Not Available

Tissue Locations

Adipose Tissue
Bladder
Brain
Erythrocyte
Fibroblasts
Intestine
Kidney
Liver
Lung
Muscle
Myocardium
Nerve Cells
Neuron
Platelet
Prostate
Skeletal Muscle
Sperm
Testes

Pathways

Name	SMPDB Link	KEGG Link
Beta Oxidation of Very Long Chain Fatty Acids	SMP00052	map01040
Carnitine Synthesis	SMP00465	Not Available
Mitochondrial Beta-Oxidation of Long Chain Saturated Fatty Acids	SMP00482	Not Available
Mitochondrial Beta-Oxidation of Short Chain Saturated Fatty Acids	SMP00480	Not Available
Oxidation of Branched Chain Fatty Acids	SMP00030	Not Available
Carnitine palmitoyl transferase deficiency (I)	SMP00538	Not Available
Lysinuric Protein Intolerance	SMP00197	Not Available
Propionic Acidemia	SMP00236	Not Available

Applications

Biological Roles

Chemical Roles

Not Available

Physical Properties

State

Solid

Appearance

White powder.

Experimental Properties

Property	Value
Melting Point	195-198°C
Boiling Point	Not Available
Solubility	2500 mg/mL

Predicted Properties

Property	Value	Source
Water Solubility	5.33 g/L	ALOGPS
logP	-2.9	ALOGPS
logP	-4.9	ChemAxon
logS	-1.6	ALOGPS
pKa (Strongest Acidic)	4.2	ChemAxon
pKa (Strongest Basic)	-3.6	ChemAxon
Physiological Charge	0	ChemAxon
Hydrogen Acceptor Count	3	ChemAxon
Hydrogen Donor Count	1	ChemAxon
Polar Surface Area	60.36 Å²	ChemAxon
Rotatable Bond Count	4	ChemAxon
Refractivity	63.49 m³·mol⁻¹	ChemAxon
Polarizability	16.93 Å³	ChemAxon
Number of Rings	0	ChemAxon
Bioavailability	1	ChemAxon
Rule of Five	Yes	ChemAxon
Ghose Filter	No	ChemAxon
Veber's Rule	No	ChemAxon
MDDR-like Rule	No	ChemAxon

Spectra

Spectrum Type	Description	Splash Key	View
Predicted GC-MS	Predicted GC-MS Spectrum - GC-MS (Non-derivatized) - 70eV, Positive	splash10-00di-9100000000-1b25dacb04c3ed5be8d0	Spectrum
Predicted GC-MS	Predicted GC-MS Spectrum - GC-MS (1 TMS) - 70eV, Positive	splash10-00di-9100000000-c15eaa190d1e28a4839a	Spectrum
Predicted GC-MS	Predicted GC-MS Spectrum - GC-MS (Non-derivatized) - 70eV, Positive	Not Available	Spectrum
Predicted GC-MS	Predicted GC-MS Spectrum - GC-MS (TMS_1_1) - 70eV, Positive	Not Available	Spectrum
Predicted GC-MS	Predicted GC-MS Spectrum - GC-MS (TMS_1_2) - 70eV, Positive	Not Available	Spectrum
Predicted GC-MS	Predicted GC-MS Spectrum - GC-MS (TMS_2_1) - 70eV, Positive	Not Available	Spectrum
Predicted GC-MS	Predicted GC-MS Spectrum - GC-MS (TBDMS_1_1) - 70eV, Positive	Not Available	Spectrum
Predicted GC-MS	Predicted GC-MS Spectrum - GC-MS (TBDMS_1_2) - 70eV, Positive	Not Available	Spectrum
Predicted GC-MS	Predicted GC-MS Spectrum - GC-MS (TBDMS_2_1) - 70eV, Positive	Not Available	Spectrum
LC-MS/MS	LC-MS/MS Spectrum - LC-ESI-QQ , positive	splash10-03di-0900000000-9b579c570aab7c7d3a21	Spectrum
LC-MS/MS	LC-MS/MS Spectrum - LC-ESI-QQ , positive	splash10-0ik9-0900000000-e37d3def2de1af5bd2f5	Spectrum
LC-MS/MS	LC-MS/MS Spectrum - LC-ESI-QQ , positive	splash10-0ue9-8900000000-cf37f0a721cd52d86e8e	Spectrum
LC-MS/MS	LC-MS/MS Spectrum - LC-ESI-QQ , positive	splash10-0r0c-9200000000-a11a4872036f3c33d25a	Spectrum
LC-MS/MS	LC-MS/MS Spectrum - LC-ESI-QQ , positive	splash10-0a4l-9000000000-2402e260a330ff1772a1	Spectrum
LC-MS/MS	LC-MS/MS Spectrum - LC-ESI-IT , positive	splash10-0w29-6900000000-d0136248acdd706e650b	Spectrum
LC-MS/MS	LC-MS/MS Spectrum - LC-ESI-QTOF , positive	splash10-0ik9-2900000000-61732bb10307f2b183ca	Spectrum
LC-MS/MS	LC-MS/MS Spectrum - LC-ESI-QTOF , positive	splash10-0zg0-9400000000-15c3db3324f1d46d3c7c	Spectrum
LC-MS/MS	LC-MS/MS Spectrum - LC-ESI-QTOF , positive	splash10-0ik9-2900000000-ee79f10dce9fc09246ec	Spectrum
Predicted LC-MS/MS	Predicted LC-MS/MS Spectrum - 10V, Positive	splash10-01ox-0900000000-3bffd5143cf8b072299e	Spectrum
Predicted LC-MS/MS	Predicted LC-MS/MS Spectrum - 20V, Positive	splash10-00kf-0900000000-e68f553bcb15d3ef5b47	Spectrum
Predicted LC-MS/MS	Predicted LC-MS/MS Spectrum - 40V, Positive	splash10-00di-9200000000-c5b43723951af6da48cf	Spectrum
Predicted LC-MS/MS	Predicted LC-MS/MS Spectrum - 10V, Negative	splash10-03di-1900000000-dd1b1a023937cdcb11af	Spectrum
Predicted LC-MS/MS	Predicted LC-MS/MS Spectrum - 20V, Negative	splash10-114i-3900000000-9f24d3bc535736149e2a	Spectrum
Predicted LC-MS/MS	Predicted LC-MS/MS Spectrum - 40V, Negative	splash10-0a4l-9000000000-632ef17d9dde38586990	Spectrum
Predicted LC-MS/MS	Predicted LC-MS/MS Spectrum - 10V, Positive	splash10-03di-3900000000-97af6636a917c0edea61	Spectrum
Predicted LC-MS/MS	Predicted LC-MS/MS Spectrum - 20V, Positive	splash10-01pc-9300000000-543e21cb6b9785149e31	Spectrum
Predicted LC-MS/MS	Predicted LC-MS/MS Spectrum - 40V, Positive	splash10-08fr-9000000000-9128d6fe96d9c7276695	Spectrum
1D NMR	1H NMR Spectrum	Not Available	Spectrum

Toxicity Profile

Route of Exposure

Intravenous, Oral. Absolute bioavailability is 15% (tablets or solution). Time to maximum plasma concentration was found to be 3.3 hours.

Mechanism of Toxicity

Levocarnitine can be synthesised within the body from the amino acids lysine or methionine. Vitamin C (ascorbic acid) is essential to the synthesis of carnitine. Levocarnitine is a carrier molecule in the transport of long chain fatty acids across the inner mitochondrial membrane. It also exports acyl groups from subcellular organelles and from cells to urine before they accumulate to toxic concentrations. Only the L isomer of carnitine (sometimes called vitamin BT) affects lipid metabolism. Levocarnitine is handled by several proteins in different pathways including carnitine transporters, carnitine translocases, carnitine acetyltransferases and carnitine palmitoyltransferases.

Metabolism

After oral administration L-carnitine which is unabsorbed is metabolized in the gastrointestinal tract by bacterial microflora. Major metabolites include trimethylamine N-oxide and [3H]-gamma-butyrobetaine. Route of Elimination: Following a single intravenous dose, 73.1 +/- 16% of the dose was excreted in the urine during the 0-24 hour interval. Post administration of oral carnitine supplements, in addition to a high carnitine diet, 58-65% of the administered radioactive dose was recovered from urine and feces in 5-11 days. Half Life: 17.4 hours (elimination) following a single intravenous dose.

Toxicity Values

LD₅₀ > 8g/kg (mouse, oral).

Lethal Dose

Not Available

Carcinogenicity (IARC Classification)

No indication of carcinogenicity to humans (not listed by IARC).

Uses/Sources

For treatment of primary systemic carnitine deficiency, a genetic impairment of normal biosynthesis or utilization of levocarnitine from dietary sources, or for the treatment of secondary carnitine deficiency resulting from an inborn error of metabolism such as glutaric aciduria II, methyl malonic aciduria, propionic acidemia, and medium chain fatty acylCoA dehydrogenase deficiency. Used therapeutically to stimulate gastric and pancreatic secretions and in the treatment of hyperlipoproteinemias. Parenteral levocarnitine is indicated for the prevention and treatment of carnitine deficiency in patients with end-stage renal disease.

Minimum Risk Level

Not Available

Health Effects

Not Available

Symptoms

Adverse effects include hypertension, fever, tachycardia and seizures.

Treatment

Not Available

Concentrations

Not Available

External Links

DrugBank ID