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Record Information
StatusDetected and Quantified
Creation Date2005-11-16 15:48:42 UTC
Update Date2020-02-26 21:22:17 UTC
Secondary Accession Numbers
  • HMDB00525
Metabolite Identification
Common Name5-Hydroxyhexanoic acid
Description5-Hydroxyhexanoic acid is a normal dicarboxylic acid degradation product of fatty acids; however, it has been found in patients with non-ketotic dicarboxylic aciduria and one patient on a diet containing excessive amounts of medium-chain triglycerides. Increased amounts of dicarboxylic acids are excreted in human urine under conditions of medium-chain triglyceride (MCT) feeding, abnormal fatty acid oxidation (FAO) and fasting. Criteria to distinguish dicarboxylic aciduria originating from MCT feeding and other conditions are needed in urinary organic acid profiling for detecting inborn errors of metabolism. Medium-chain triglycerides (MCTs) are absorbed and metabolized differently from long-chain triglycerides (LCTs). MCTs may be useful as a dietary substitute in a variety of clinical disorders. Urinary excretion of 5-hydroxyhexanoic acid, the (omega-1) hydroxylation product, was increased during MCT feeding as compared with LCT feeding in patients with non-insulin-dependent diabetes mellitus (PMID: 6897376 , 2239769 , 8596483 ). Moreover, 5-hydroxyhexanoic acid is also found to be associated with Medium chain acyl-CoA dehydrogenase deficiency (MCADD), which is also an inborn error of metabolism. 5-Hydroxyhexanoic acid has be found to be a microbial metabolite (PMID: 20615997 ).
5-Hydroxy caproic acidChEBI
5-Hydroxy-hexanoic acidChEBI
5-Hydroxycaproic acidChEBI
5-OH-Caproic acidChEBI
5-Hydroxy caproateGenerator
5-Hydroxyhexanoic acidMeSH
Chemical FormulaC6H12O3
Average Molecular Weight132.1577
Monoisotopic Molecular Weight132.07864425
IUPAC Name5-hydroxyhexanoic acid
Traditional Name5-hydroxyhexanoic acid
CAS Registry Number44843-89-2
InChI Identifier
Chemical Taxonomy
Description belongs to the class of organic compounds known as medium-chain fatty acids. These are fatty acids with an aliphatic tail that contains between 4 and 12 carbon atoms.
KingdomOrganic compounds
Super ClassLipids and lipid-like molecules
ClassFatty Acyls
Sub ClassFatty acids and conjugates
Direct ParentMedium-chain fatty acids
Alternative Parents
  • Medium-chain fatty acid
  • Hydroxy fatty acid
  • Secondary alcohol
  • Monocarboxylic acid or derivatives
  • Carboxylic acid
  • Carboxylic acid derivative
  • Organic oxygen compound
  • Organic oxide
  • Hydrocarbon derivative
  • Organooxygen compound
  • Carbonyl group
  • Alcohol
  • Aliphatic acyclic compound
Molecular FrameworkAliphatic acyclic compounds
External Descriptors
Physiological effect

Health effect:


Route of exposure:


Biological location:


Naturally occurring process:


Biological role:

Physical Properties
Experimental Properties
Melting PointNot AvailableNot Available
Boiling PointNot AvailableNot Available
Water SolubilityNot AvailableNot Available
LogPNot AvailableNot Available
Predicted Properties
Water Solubility128 g/LALOGPS
pKa (Strongest Acidic)4.71ChemAxon
pKa (Strongest Basic)-1.6ChemAxon
Physiological Charge-1ChemAxon
Hydrogen Acceptor Count3ChemAxon
Hydrogen Donor Count2ChemAxon
Polar Surface Area57.53 ŲChemAxon
Rotatable Bond Count4ChemAxon
Refractivity32.82 m³·mol⁻¹ChemAxon
Polarizability14.06 ųChemAxon
Number of Rings0ChemAxon
Rule of FiveYesChemAxon
Ghose FilterNoChemAxon
Veber's RuleNoChemAxon
MDDR-like RuleNoChemAxon
Spectrum TypeDescriptionSplash KeyView
Predicted GC-MSPredicted GC-MS Spectrum - GC-MS (Non-derivatized) - 70eV, Positivesplash10-0077-9100000000-13a584fc9ff05431f359Spectrum
Predicted GC-MSPredicted GC-MS Spectrum - GC-MS (2 TMS) - 70eV, Positivesplash10-007c-9420000000-7b0146069089183f6082Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Positivesplash10-014j-6900000000-d6721c752b62f7410232Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Positivesplash10-014i-9300000000-74040f00b17b4041c299Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Positivesplash10-066r-9000000000-6f7de79a29b2b4c5a8ecSpectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Negativesplash10-001i-2900000000-7460b1bb2fffef236fdeSpectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Negativesplash10-01qi-8900000000-b62d68d9bf86cee6fa5aSpectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Negativesplash10-0a4l-9000000000-ca5de42d9cc939f4610bSpectrum
Biological Properties
Cellular Locations
  • Cytoplasm
Biospecimen Locations
  • Blood
  • Feces
  • Urine
Tissue LocationsNot Available
Normal Concentrations
BloodExpected but not Quantified Not AvailableNot Available
    FecesDetected but not Quantified Adult (>18 years old)Both
    FecesDetected but not Quantified Adult (>18 years old)Both
    FecesDetected but not Quantified Adult (>18 years old)Both
    FecesDetected but not Quantified Adult (>18 years old)Both
    FecesDetected but not Quantified Not SpecifiedNot Specified
    UrineDetected and Quantified1.1-2.9 umol/mmol creatinineAdult (>18 years old)FemaleNormal details
    UrineDetected and Quantified0.7 (0.1-1.2) umol/mmol creatinineAdolescent (13-18 years old)Both
    UrineDetected and Quantified2.7 (0.8-5.7) umol/mmol creatinineAdult (>18 years old)Both
    UrineDetected but not Quantified Adult (>18 years old)BothNormal details
    UrineDetected and Quantified0.86-1.8 umol/mmol creatinineAdult (>18 years old)MaleNormal details
    UrineDetected and Quantified2.0 (0.1-11.2) umol/mmol creatinineNewborn (0-30 days old)BothNormal details
    UrineDetected and Quantified4.0 (0.1-6.5) umol/mmol creatinineInfant (0-1 year old)BothNormal details
    UrineDetected and Quantified1.0 (0.1-1.6) umol/mmol creatinineChildren (1-13 years old)Both
    Abnormal Concentrations
    FecesDetected but not Quantified Adult (>18 years old)Both
    Colorectal cancer
    FecesDetected but not Quantified Adult (>18 years old)BothColorectal Cancer details
    FecesDetected but not Quantified Adult (>18 years old)Both
    Colorectal cancer
    UrineDetected and Quantified15-700 umol/mmol creatinineChildren (1 - 13 years old)BothMedium Chain Acyl-CoA Dehydrogenase Deficiency details
    UrineDetected and Quantified47.146-384.404 umol/mmol creatinineChildren (1-13 years old)Not SpecifiedMedium Chain Acyl-CoA Dehydrogenase Deficiency details
    UrineDetected but not Quantified Adult (>18 years old)Both
    Bladder cancer
    UrineDetected and Quantified3.5 (0.0-7.0) umol/mmol creatinineAdult (>18 years old)BothMedium Chain Acyl-CoA Dehydrogenase Deficiency
      • MetaGene: Metabol...
    Associated Disorders and Diseases
    Disease References
    Colorectal cancer
    1. Brown DG, Rao S, Weir TL, O'Malia J, Bazan M, Brown RJ, Ryan EP: Metabolomics and metabolic pathway networks from human colorectal cancers, adjacent mucosa, and stool. Cancer Metab. 2016 Jun 6;4:11. doi: 10.1186/s40170-016-0151-y. eCollection 2016. [PubMed:27275383 ]
    2. Sinha R, Ahn J, Sampson JN, Shi J, Yu G, Xiong X, Hayes RB, Goedert JJ: Fecal Microbiota, Fecal Metabolome, and Colorectal Cancer Interrelations. PLoS One. 2016 Mar 25;11(3):e0152126. doi: 10.1371/journal.pone.0152126. eCollection 2016. [PubMed:27015276 ]
    3. Goedert JJ, Sampson JN, Moore SC, Xiao Q, Xiong X, Hayes RB, Ahn J, Shi J, Sinha R: Fecal metabolomics: assay performance and association with colorectal cancer. Carcinogenesis. 2014 Sep;35(9):2089-96. doi: 10.1093/carcin/bgu131. Epub 2014 Jul 18. [PubMed:25037050 ]
    Medium Chain Acyl-CoA Dehydrogenase Deficiency
    1. Gregersen N, Kolvraa S, Rasmussen K, Mortensen PB, Divry P, David M, Hobolth N: General (medium-chain) acyl-CoA dehydrogenase deficiency (non-ketotic dicarboxylic aciduria): quantitative urinary excretion pattern of 23 biologically significant organic acids in three cases. Clin Chim Acta. 1983 Aug 15;132(2):181-91. [PubMed:6616873 ]
    2. Duran M, De Klerk JB, Wadman SK, Bruinvis L, Ketting D: The differential diagnosis of dicarboxylic aciduria. J Inherit Metab Dis. 1984;7 Suppl 1:48-51. [PubMed:6434845 ]
    3. G.Frauendienst-Egger, Friedrich K. Trefz (2017). MetaGene: Metabolic & Genetic Information Center (MIC: METAGENE consortium.
    Associated OMIM IDs
    • 114500 (Colorectal cancer)
    • 201450 (Medium Chain Acyl-CoA Dehydrogenase Deficiency)
    DrugBank IDNot Available
    Phenol Explorer Compound IDNot Available
    FooDB IDFDB022093
    KNApSAcK IDNot Available
    Chemspider ID149280
    KEGG Compound IDNot Available
    BioCyc IDNot Available
    BiGG IDNot Available
    Wikipedia LinkNot Available
    METLIN ID5510
    PubChem Compound170748
    PDB IDNot Available
    ChEBI ID131434
    Food Biomarker OntologyNot Available
    VMH IDNot Available
    Synthesis ReferenceValentin, H. E.; Schoenebaum, A.; Steinbuechel, A. Identification of 5-hydroxyhexanoic acid, 4-hydroxyheptanoic acid and 4-hydroxyoctanoic acid as new constituents of bacterial polyhydroxyalkanoic acids. Applied Microbiology and Biotechnology (1996), 46(3), 261-267.
    Material Safety Data Sheet (MSDS)Not Available
    General References
    1. Niwa T, Meada K, Ohki T, Saito A, Tsuchida I: Gas chromatographic-mass spectrometric profile of organic acids in urine and serum of diabetic ketotic patients. J Chromatogr. 1981 Sep 11;225(1):1-8. [PubMed:6795215 ]
    2. Boulat O, Gradwohl M, Matos V, Guignard JP, Bachmann C: Organic acids in the second morning urine in a healthy Swiss paediatric population. Clin Chem Lab Med. 2003 Dec;41(12):1642-58. [PubMed:14708889 ]
    3. Guneral F, Bachmann C: Age-related reference values for urinary organic acids in a healthy Turkish pediatric population. Clin Chem. 1994 Jun;40(6):862-6. [PubMed:8087979 ]
    4. Loftus NJ, Laird WJ, Steel GT, Wilks MF, Woollen BH: Metabolism and pharmacokinetics of deuterium-labelled di-2-(ethylhexyl) adipate (DEHA) in humans. Food Chem Toxicol. 1993 Sep;31(9):609-14. [PubMed:8406236 ]
    5. Kamerling JP, Duran M, Bruinvis L, Ketting D, Wadman SK, Vliegenthart JF: The absolute configuration of urinary 5-hydroxyhexanoic acid - a product of fatty acid (omega-1)-oxidation - in patients with non-ketotic dicarboxylic aciduria. Clin Chim Acta. 1982 Nov 10;125(3):247-54. [PubMed:6897376 ]
    6. Brass EP, Tserng KY, Eckel RH: Urinary organic acid excretion during feeding of medium-chain or long-chain triglyceride diets in patients with non-insulin-dependent diabetes mellitus. Am J Clin Nutr. 1990 Nov;52(5):923-6. [PubMed:2239769 ]
    7. Tserng KY, Griffin RL, Kerr DS: Distinction of dicarboxylic aciduria due to medium-chain triglyceride feeding from that due to abnormal fatty acid oxidation and fasting in children. Metabolism. 1996 Feb;45(2):162-7. [PubMed:8596483 ]
    8. van Duynhoven J, Vaughan EE, Jacobs DM, Kemperman RA, van Velzen EJ, Gross G, Roger LC, Possemiers S, Smilde AK, Dore J, Westerhuis JA, Van de Wiele T: Metabolic fate of polyphenols in the human superorganism. Proc Natl Acad Sci U S A. 2011 Mar 15;108 Suppl 1:4531-8. doi: 10.1073/pnas.1000098107. Epub 2010 Jun 25. [PubMed:20615997 ]