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Record Information
StatusExpected but not Quantified
Creation Date2006-12-06 15:50:26 UTC
Update Date2017-12-20 21:17:37 UTC
Secondary Accession Numbers
  • HMDB05453
Metabolite Identification
Common NameTG(18:1(9Z)/18:1(9Z)/18:1(9Z))
DescriptionTG(18:1(9Z)/18:1(9Z)/18:1(9Z)) or Triolein is a monoacid triglyceride. Triglycerides (TGs) are also known as triacylglycerols or triacylglycerides. TGs are fatty acid triesters of glycerol and may be divided into three general types with respect to their acyl substituents. They are simple or monoacid if they contain only one type of fatty acid, diacid if they contain two types of fatty acids and triacid if three different acyl groups. Chain lengths of the fatty acids in naturally occurring triglycerides can be of varying lengths and saturations but 16, 18 and 20 carbons are the most common. TGs are the main constituent of vegetable oil and animal fats. TGs are major components of very low density lipoprotein (VLDL) and chylomicrons, play an important role in metabolism as energy sources and transporters of dietary fat. They contain more than twice the energy (9 kcal/g) of carbohydrates and proteins. In the intestine, triglycerides are split into glycerol and fatty acids (this process is called lipolysis) (with the help of lipases and bile secretions), which can then move into blood vessels. The triglycerides are rebuilt in the blood from their fragments and become constituents of lipoproteins, which deliver the fatty acids to and from fat cells among other functions. Various tissues can release the free fatty acids and take them up as a source of energy. Fat cells can synthesize and store triglycerides. When the body requires fatty acids as an energy source, the hormone glucagon signals the breakdown of the triglycerides by hormone-sensitive lipase to release free fatty acids. As the brain cannot utilize fatty acids as an energy source, the glycerol component of triglycerides can be converted into glucose for brain fuel when it is broken down. (, TAGs can serve as fatty acid stores in all cells, but primarily in adipocytes of adipose tissue. The major building block for the synthesis of triacylglycerides, in non-adipose tissue, is glycerol. Adipocytes lack glycerol kinase and so must use another route to TAG synthesis. Specifically, dihydroxyacetone phosphate (DHAP), which is produced during glycolysis, is the precursor for TAG synthesis in adipose tissue. DHAP can also serve as a TAG precursor in non-adipose tissues, but does so to a much lesser extent than glycerol. The use of DHAP for the TAG backbone depends on whether the synthesis of the TAGs occurs in the mitochondria and ER or the ER and the peroxisomes. The ER/mitochondria pathway requires the action of glycerol-3-phosphate dehydrogenase to convert DHAP to glycerol-3-phosphate. Glycerol-3-phosphate acyltransferase then esterifies a fatty acid to glycerol-3-phosphate thereby generating lysophosphatidic acid. The ER/peroxisome reaction pathway uses the peroxisomal enzyme DHAP acyltransferase to acylate DHAP to acyl-DHAP which is then reduced by acyl-DHAP reductase. The fatty acids that are incorporated into TAGs are activated to acyl-CoAs through the action of acyl-CoA synthetases. Two molecules of acyl-CoA are esterified to glycerol-3-phosphate to yield 1,2-diacylglycerol phosphate (also known as phosphatidic acid). The phosphate is then removed by phosphatidic acid phosphatase (PAP1), to generate 1,2-diacylglycerol. This diacylglycerol serves as the substrate for addition of the third fatty acid to make TAG. Intestinal monoacylglycerols, derived from dietary fats, can also serve as substrates for the synthesis of 1,2-diacylglycerols.
(Z)-9-Octadecenoic acid, 1,2,3-propanetriyl esterChEBI
Glycerin trioleateChEBI
Glycerol trioleateChEBI
Glycerol trioleinChEBI
Glycerol, tri(cis-9-octadecenoate)ChEBI
Glyceryl trioleateChEBI
Oleic acid triglycerideChEBI
Oleic triglycerideChEBI
Oleyl triglycerideChEBI
Propane-1,2,3-triyl (9Z,9'z,9''z)tris-octadec-9-enoateChEBI
(Z)-9-Octadecenoate, 1,2,3-propanetriyl esterGenerator
Glycerin trioleic acidGenerator
Glycerol trioleic acidGenerator
Glycerol, tri(cis-9-octadecenoic acid)Generator
Glyceryl trioleic acidGenerator
Glyceryl-1,2,3-trioleic acidGenerator
Oleate triglycerideGenerator
Propane-1,2,3-triyl (9Z,9'z,9''z)tris-octadec-9-enoic acidGenerator
Trioleate glycerinMeSH
Trioleyl glycerolMeSH
Glycerol, trioleylMeSH
Trioleate, glycerolMeSH
1-(9Z-octadecenoyl)-2-(9Z-octadecenoyl)-3-(9Z-octadecenoyl)-glycerol; TAG(18:1/18:1/18:1)Lipid Annotator
TriacylglycerolLipid Annotator
TG(18:1/18:1/18:1)Lipid Annotator
TG(54:3)Lipid Annotator
TG(18:1(9Z)/18:1(9Z)/18:1(9Z))Lipid Annotator
Tracylglycerol(18:1/18:1/18:1)Lipid Annotator
TriglycerideLipid Annotator
Tracylglycerol(54:3)Lipid Annotator
1-oleoyl-2-oleoyl-3-oleoyl-glycerolLipid Annotator
TAG(54:3)Lipid Annotator
1-(9Z-octadecenoyl)-2-(9Z-octadecenoyl)-3-(9Z-octadecenoyl)-glycerolLipid Annotator
TAG(18:1/18:1/18:1)Lipid Annotator
Chemical FormulaC57H104O6
Average Molecular Weight885.4321
Monoisotopic Molecular Weight884.78329106
IUPAC Name1,3-bis[(9Z)-octadec-9-enoyloxy]propan-2-yl (9Z)-octadec-9-enoate
Traditional Nametriolein
CAS Registry Number122-32-7
InChI Identifier
Chemical Taxonomy
DescriptionThis compound belongs to the class of organic compounds known as triacylglycerols. These are glycerides consisting of three fatty acid chains covalently bonded to a glycerol molecule through ester linkages.
KingdomOrganic compounds
Super ClassLipids and lipid-like molecules
Sub ClassTriradylcglycerols
Direct ParentTriacylglycerols
Alternative Parents
  • Triacyl-sn-glycerol
  • Tricarboxylic acid or derivatives
  • Fatty acid ester
  • Fatty acyl
  • Carboxylic acid ester
  • 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:


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Naturally occurring process:


Biological role:

Industrial application:

Physical Properties
Experimental Properties
Melting Point-32 °CNot Available
Boiling PointNot AvailableNot Available
Water SolubilityNot AvailableNot Available
LogPNot AvailableNot Available
Predicted Properties
Water Solubility6.1e-06 g/LALOGPS
pKa (Strongest Basic)-6.6ChemAxon
Physiological Charge0ChemAxon
Hydrogen Acceptor Count3ChemAxon
Hydrogen Donor Count0ChemAxon
Polar Surface Area78.9 ŲChemAxon
Rotatable Bond Count53ChemAxon
Refractivity272.25 m³·mol⁻¹ChemAxon
Polarizability116.96 ųChemAxon
Number of Rings0ChemAxon
Rule of FiveYesChemAxon
Ghose FilterYesChemAxon
Veber's RuleYesChemAxon
MDDR-like RuleYesChemAxon
Spectrum TypeDescriptionSplash Key
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Positivesplash10-0udi-0000000009-7ebc474373ce1c8c3388View in MoNA
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Positivesplash10-0udi-0000000009-7ebc474373ce1c8c3388View in MoNA
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Positivesplash10-0udr-0000009061-c361cdac983d0cdffd59View in MoNA
1D NMR1H NMR SpectrumNot AvailableView in JSpectraViewer
Biological Properties
Cellular Locations
  • Extracellular
  • Membrane
Biospecimen LocationsNot Available
Tissue LocationNot Available
Normal Concentrations
Not Available
Abnormal Concentrations
Not Available
Predicted Concentrations
BiospecimenValueOriginal ageOriginal sexOriginal conditionComments
Blood28.377 +/- 7.043 uMAdult (>18 years old)BothNormal (Most Probable)Calculated using MetaboAnalyst
Blood175.389 +/- 30.286 uMAdult (>18 years old)BothNormal (Upper Limit)Calculated using MetaboAnalyst
Associated Disorders and Diseases
Disease ReferencesNone
Associated OMIM IDsNone
DrugBank IDNot Available
Phenol Explorer Compound IDNot Available
FoodDB IDNot Available
KNApSAcK IDNot Available
Chemspider IDNot Available
KEGG Compound IDNot Available
BioCyc IDCPD-11691
BiGG IDNot Available
Wikipedia LinkTriolein
METLIN IDNot Available
PubChem Compound5497163
PDB IDNot Available
ChEBI ID53753
Synthesis ReferenceDesnuelle, P.; Naudet, M. Isomerization of oleic acid during the synthesis of triolein. Bull. soc. chim. (1945), 12 998-1001. CAN 40:19192 AN 1946:19192 CAPLUS
Material Safety Data Sheet (MSDS)Download (PDF)
General References
  1. Hollebeeck S, Borlon F, Schneider YJ, Larondelle Y, Rogez H: Development of a standardised human in vitro digestion protocol based on macronutrient digestion using response surface methodology. Food Chem. 2013 Jun 1;138(2-3):1936-44. doi: 10.1016/j.foodchem.2012.11.041. Epub 2012 Nov 17. [PubMed:23411328 ]
  2. Wang Y, Wang YJ, Wang L, Fang GD, Cang L, Herath HM, Zhou DM: Reducing the bioavailability of PCBs in soil to plant by biochars assessed with triolein-embedded cellulose acetate membrane technique. Environ Pollut. 2013 Mar;174:250-6. doi: 10.1016/j.envpol.2012.12.004. Epub 2012 Dec 29. [PubMed:23279904 ]

Only showing the first 10 proteins. There are 26 proteins in total.


General function:
Involved in catalytic activity
Specific function:
Not Available
Gene Name:
Uniprot ID:
Molecular weight:
General function:
Involved in catalytic activity
Specific function:
Hepatic lipase has the capacity to catalyze hydrolysis of phospholipids, mono-, di-, and triglycerides, and acyl-CoA thioesters. It is an important enzyme in HDL metabolism. Hepatic lipase binds heparin.
Gene Name:
Uniprot ID:
Molecular weight:
General function:
Involved in catalytic activity
Specific function:
May function as inhibitor of dietary triglyceride digestion. Lacks detectable lipase activity towards triglycerides, diglycerides, phosphatidylcholine, galactolipids or cholesterol esters (in vitro) (By similarity).
Gene Name:
Uniprot ID:
Molecular weight:
Not Available
General function:
Involved in metabolic process
Specific function:
Multifunctional enzyme which has both triacylglycerol lipase and acylglycerol O-acyltransferase activities.
Gene Name:
Uniprot ID:
Molecular weight:
General function:
Involved in lipid metabolic process
Specific function:
Not Available
Gene Name:
Uniprot ID:
Molecular weight:
General function:
Involved in catalytic activity
Specific function:
Has phospholipase and triglyceride lipase activities. Hydrolyzes high density lipoproteins (HDL) more efficiently than other lipoproteins. Binds heparin.
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Lipid transport and metabolism
Specific function:
Catalyzes fat and vitamin absorption. Acts in concert with pancreatic lipase and colipase for the complete digestion of dietary triglycerides.
Gene Name:
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Molecular weight:
General function:
Involved in diacylglycerol O-acyltransferase activity
Specific function:
Catalyzes the terminal and only committed step in triacylglycerol synthesis by using diacylglycerol and fatty acyl CoA as substrates. In contrast to DGAT2 it is not essential for survival. May be involved in VLDL (very low density lipoprotein) assembly. In liver, plays a role in esterifying exogenous fatty acids to glycerol. Functions as the major acyl-CoA retinol acyltransferase (ARAT) in the skin, where it acts to maintain retinoid homeostasis and prevent retinoid toxicity leading to skin and hair disorders.
Gene Name:
Uniprot ID:
Molecular weight:
General function:
Involved in catalytic activity
Specific function:
Lipase with broad substrate specificity. Can hydrolyze both phospholipids and galactolipids. Acts preferentially on monoglycerides, phospholipids and galactolipids. Contributes to milk fat hydrolysis.
Gene Name:
Uniprot ID:
Molecular weight:
General function:
Involved in catalytic activity
Specific function:
The primary function of this lipase is the hydrolysis of triglycerides of circulating chylomicrons and very low density lipoproteins (VLDL). Binding to heparin sulfate proteogylcans at the cell surface is vital to the function. The apolipoprotein, APOC2, acts as a coactivator of LPL activity in the presence of lipids on the luminal surface of vascular endothelium (By similarity).
Gene Name:
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Molecular weight:


General function:
Involved in lipid transporter activity
Specific function:
Catalyzes the transport of triglyceride, cholesteryl ester, and phospholipid between phospholipid surfaces. Required for the secretion of plasma lipoproteins that contain apolipoprotein B
Gene Name:
Uniprot ID:
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Only showing the first 10 proteins. There are 26 proteins in total.