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Record Information
StatusExpected but not Quantified
Creation Date2006-12-06 15:50:25 UTC
Update Date2017-12-20 21:14:57 UTC
Secondary Accession Numbers
  • HMDB05366
Metabolite Identification
Common NameTG(16:0/18:0/20:0)
DescriptionTG(16:0/18:0/20:0)[iso6] is a monoarachidic acid triglyceride. Triglycerides (TGs) are also known as triacylglycerols or triacylglycerides, meaning that they are glycerides in which the glycerol is esterified with three fatty acid groups (i.e. fatty acid tri-esters of glycerol). TGs 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. TG(16:0/18:0/20:0)[iso6], in particular, consists of one chain of palmitic acid at the C-1 position, one chain of stearic acid at the C-2 position and one chain of arachidic acid at the C-3 position. 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. (, 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.
1-hexadecanoyl-2-octadecanoyl-3-eicosanoyl-glycerol; TG(54:0)Lipid Annotator
TriacylglycerolLipid Annotator
Tracylglycerol(16:0/18:0/20:0)Lipid Annotator
1-palmitoyl-2-stearoyl-3-arachidonyl-glycerolLipid Annotator
TriglycerideLipid Annotator
TG(16:0/18:0/20:0)Lipid Annotator
TAG(16:0/18:0/20:0)Lipid Annotator
Tracylglycerol(54:0)Lipid Annotator
TAG(54:0)Lipid Annotator
1-hexadecanoyl-2-octadecanoyl-3-eicosanoyl-glycerolLipid Annotator
TG(54:0)Lipid Annotator
Chemical FormulaC57H110O6
Average Molecular Weight891.501
Monoisotopic Molecular Weight890.830241262
IUPAC Name(2S)-3-(hexadecanoyloxy)-2-(octadecanoyloxy)propyl icosanoate
Traditional Name(2S)-3-(hexadecanoyloxy)-2-(octadecanoyloxy)propyl icosanoate
CAS Registry NumberNot Available
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 DescriptorsNot Available

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Physical Properties
Experimental Properties
Melting PointNot AvailableNot Available
Boiling PointNot AvailableNot Available
Water SolubilityNot AvailableNot Available
LogPNot AvailableNot Available
Predicted Properties
Water Solubility1.1e-05 g/LALOGPS
pKa (Strongest Basic)-6.6ChemAxon
Physiological Charge0ChemAxon
Hydrogen Acceptor Count3ChemAxon
Hydrogen Donor Count0ChemAxon
Polar Surface Area78.9 ŲChemAxon
Rotatable Bond Count56ChemAxon
Refractivity268.9 m³·mol⁻¹ChemAxon
Polarizability122.02 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, Positivesplash10-0a4i-0000000009-2e72f9bb2fcaaf828b27View in MoNA
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Positivesplash10-0a4i-0000000009-2e72f9bb2fcaaf828b27View in MoNA
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Positivesplash10-0a73-0000049030-67ab0acd6989c79e164eView in MoNA
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Negativesplash10-06rl-0092001010-5a56d3bb38fb9afdd2e1View in MoNA
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Negativesplash10-08fr-0094000000-4b16f74a2401c1225bb5View in MoNA
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Negativesplash10-0btc-2092000000-c5c22f18c83a7ae8b877View in MoNA
Biological Properties
Cellular Locations
  • Extracellular
  • Membrane
Biofluid LocationsNot Available
Tissue LocationNot Available
De Novo Triacylglycerol Biosynthesis TG(16:0/18:0/20:0)ThumbThumb?image type=greyscaleThumb?image type=simpleNot Available
Normal Concentrations
Not Available
Abnormal Concentrations
Not Available
Predicted Concentrations
BiofluidValueOriginal ageOriginal sexOriginal conditionComments
Blood0.012800929 +/- 0.00423942 uMAdult (>18 years old)BothNormal (Most Probable)Calculated using MetaboAnalyst
Blood2.066666667 +/- 0.493288286 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 IDNot Available
BiGG IDNot Available
Wikipedia LinkNot Available
METLIN IDNot Available
PubChem CompoundNot Available
PDB IDNot Available
ChEBI IDNot Available
Synthesis ReferenceNot Available
Material Safety Data Sheet (MSDS)Not Available
General ReferencesNot Available

Only showing the first 10 proteins. There are 30 proteins in total.


General function:
Involved in catalytic activity
Specific function:
Not Available
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Involved in catalytic activity
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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.
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Involved in lipid metabolic process
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Crucial for the intracellular hydrolysis of cholesteryl esters and triglycerides that have been internalized via receptor-mediated endocytosis of lipoprotein particles. Important in mediating the effect of LDL (low density lipoprotein) uptake on suppression of hydroxymethylglutaryl-CoA reductase and activation of endogenous cellular cholesteryl ester formation.
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Involved in catalytic activity
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May function as inhibitor of dietary triglyceride digestion. Lacks detectable lipase activity towards triglycerides, diglycerides, phosphatidylcholine, galactolipids or cholesterol esters (in vitro) (By similarity).
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Not Available
General function:
Involved in metabolic process
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Multifunctional enzyme which has both triacylglycerol lipase and acylglycerol O-acyltransferase activities.
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Involved in lipid metabolic process
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Not Available
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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
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Catalyzes fat and vitamin absorption. Acts in concert with pancreatic lipase and colipase for the complete digestion of dietary triglycerides.
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Involved in diacylglycerol O-acyltransferase activity
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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.
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Involved in catalytic activity
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Lipase with broad substrate specificity. Can hydrolyze both phospholipids and galactolipids. Acts preferentially on monoglycerides, phospholipids and galactolipids. Contributes to milk fat hydrolysis.
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General function:
Involved in lipid transporter activity
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Catalyzes the transport of triglyceride, cholesteryl ester, and phospholipid between phospholipid surfaces. Required for the secretion of plasma lipoproteins that contain apolipoprotein B
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Only showing the first 10 proteins. There are 30 proteins in total.