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Record Information
Version4.0
StatusDetected and Quantified
Creation Date2006-05-22 14:17:42 UTC
Update Date2019-07-23 05:45:23 UTC
HMDB IDHMDB0002209
Secondary Accession Numbers
  • HMDB02209
Metabolite Identification
Common NameEquol
DescriptionEquol is a metabolite of daidzein, a phytoestrogen common in the human diet and abundant in soy. Intestinal bacteria in humans can reduce daidzein to equol, and can be found in normal human urine. The clinical effectiveness of soy isoflavones may be a function of the ability to biotransform soy isoflavones to the more potent estrogenic metabolite, equol, which may enhance the actions of soy isoflavones, owing to its greater affinity for estrogen receptors, unique antiandrogenic properties, and superior antioxidant activity. However, not all individuals consuming daidzein produce equol. Only approximately one-third to one-half of the population is able to metabolize daidzein to equol. This high variability in equol production is presumably attributable to interindividual differences in the composition of the intestinal microflora, which may play an important role in the mechanisms of action of isoflavones. (PMID: 17579895 , 17579894 ). Equol can be found in Bacteroides, Bifidobacterium, Enterococcus, Lactobacillus and Eggerthella (PMID: 20519412 ; PMID: 18838805 ).
Structure
Data?1563860723
Synonyms
ValueSource
AUS-131(S)-equolHMDB
(-)-(S)-EquolHMDB
(-)-EquolHMDB
(S)-(-)-4',7-IsoflavandiolHMDB
(S)-3,4-Dihydro-3-(4-hydroxyphenyl)-2H-1-benzopyran-7-olHMDB
(S)-EquolHMDB
4',7-DihydroxyisoflavanHMDB
4',7-IsoflavandiolHMDB
3'-Hydroxy-equolHMDB
4' Methoxy 7 isoflavanolHMDB
4'-O-Methyl equolHMDB
6'-Hydroxy-equolHMDB
Equol, 4'-O-methylHMDB
3' Hydroxy equolHMDB
4'-Methoxy-7-isoflavanolHMDB
6' Hydroxy equolHMDB
4' O Methyl equolHMDB
(+-)-Isomer OF equolHMDB
Chemical FormulaC15H14O3
Average Molecular Weight242.2699
Monoisotopic Molecular Weight242.094294314
IUPAC Name(3S)-3-(4-hydroxyphenyl)-3,4-dihydro-2H-1-benzopyran-7-ol
Traditional Name(-)-equol
CAS Registry Number531-95-3
SMILES
OC1=CC=C(C=C1)[C@H]1COC2=CC(O)=CC=C2C1
InChI Identifier
InChI=1S/C15H14O3/c16-13-4-1-10(2-5-13)12-7-11-3-6-14(17)8-15(11)18-9-12/h1-6,8,12,16-17H,7,9H2/t12-/m1/s1
InChI KeyADFCQWZHKCXPAJ-GFCCVEGCSA-N
Chemical Taxonomy
Description belongs to the class of organic compounds known as isoflavanols. These are polycyclic compounds containing a hydroxylated isoflavan skeleton.
KingdomOrganic compounds
Super ClassPhenylpropanoids and polyketides
ClassIsoflavonoids
Sub ClassIsoflavans
Direct ParentIsoflavanols
Alternative Parents
Substituents
  • Hydroxyisoflavonoid
  • Isoflavanol
  • Chromane
  • Benzopyran
  • 1-benzopyran
  • Alkyl aryl ether
  • 1-hydroxy-2-unsubstituted benzenoid
  • Phenol
  • Monocyclic benzene moiety
  • Benzenoid
  • Ether
  • Oxacycle
  • Organoheterocyclic compound
  • Organooxygen compound
  • Hydrocarbon derivative
  • Organic oxygen compound
  • Aromatic heteropolycyclic compound
Molecular FrameworkAromatic heteropolycyclic compounds
External Descriptors
Ontology
Physiological effect

Health effect:

Disposition

Source:

Biological location:

Role

Industrial application:

Physical Properties
StateSolid
Experimental Properties
PropertyValueReference
Melting Point189.5 °CNot Available
Boiling PointNot AvailableNot Available
Water SolubilityNot AvailableNot Available
LogPNot AvailableNot Available
Predicted Properties
PropertyValueSource
Water Solubility0.044 g/LALOGPS
logP2.91ALOGPS
logP3.19ChemAxon
logS-3.7ALOGPS
pKa (Strongest Acidic)9.63ChemAxon
pKa (Strongest Basic)-4.9ChemAxon
Physiological Charge0ChemAxon
Hydrogen Acceptor Count3ChemAxon
Hydrogen Donor Count2ChemAxon
Polar Surface Area49.69 ŲChemAxon
Rotatable Bond Count1ChemAxon
Refractivity68.96 m³·mol⁻¹ChemAxon
Polarizability25.81 ųChemAxon
Number of Rings3ChemAxon
Bioavailability1ChemAxon
Rule of FiveYesChemAxon
Ghose FilterYesChemAxon
Veber's RuleYesChemAxon
MDDR-like RuleYesChemAxon
Spectra
Spectrum TypeDescriptionSplash KeyView
Predicted GC-MSPredicted GC-MS Spectrum - GC-MS (Non-derivatized) - 70eV, Positivesplash10-03dl-2590000000-de6943a0e29cb74d29c4JSpectraViewer | MoNA
Predicted GC-MSPredicted GC-MS Spectrum - GC-MS (2 TMS) - 70eV, Positivesplash10-00di-6439000000-bd3446db9a81b442105bJSpectraViewer | MoNA
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Positivesplash10-006x-0890000000-7e7596ef550328bb2d8bJSpectraViewer | MoNA
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Positivesplash10-00di-0950000000-eb2fba880af94e2ffaa4JSpectraViewer | MoNA
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Positivesplash10-0adi-5910000000-ae99af1d6277808c807aJSpectraViewer | MoNA
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Negativesplash10-0006-0390000000-9e81ff09baf049465955JSpectraViewer | MoNA
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Negativesplash10-0006-0390000000-23c63d12aef21bc1a2feJSpectraViewer | MoNA
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Negativesplash10-0603-4930000000-18ce0b21dd8e144014a5JSpectraViewer | MoNA
Biological Properties
Cellular Locations
  • Membrane (predicted from logP)
Biospecimen Locations
  • Blood
  • Urine
Tissue LocationsNot Available
Pathways
Normal Concentrations
BiospecimenStatusValueAgeSexConditionReferenceDetails
BloodDetected and Quantified0.0006 (0.00057 - 0.00066) uMAdult (>18 years old)MaleNormal details
BloodDetected and Quantified0.0006 (0.00057 - 0.0007) uMAdult (>18 years old)FemaleNormal details
BloodDetected and Quantified0.0002 uMAdult (>18 years old)FemaleNormal details
BloodDetected and Quantified0.000413 uMAdult (>18 years old)FemaleNormal details
BloodDetected and Quantified0.00056 uMAdult (>18 years old)FemaleNormal details
BloodDetected and Quantified0.0006 uMAdult (>18 years old)FemaleNormal details
UrineExpected but not Quantified Not AvailableNot AvailableConsuming polyphenols described by Phenol-Explorer entry 866 details
UrineExpected but not Quantified Not AvailableNot AvailableConsuming polyphenols described by Phenol-Explorer entry 866 details
UrineExpected but not Quantified Not AvailableNot AvailableConsuming polyphenols described by Phenol-Explorer entry 866 details
UrineExpected but not Quantified Not AvailableNot AvailableConsuming polyphenols described by Phenol-Explorer entry 866 details
UrineExpected but not Quantified Not AvailableNot AvailableConsuming polyphenols described by Phenol-Explorer entry 866 details
UrineExpected but not Quantified Not AvailableNot AvailableConsuming polyphenols described by Phenol-Explorer entry 866 details
UrineExpected but not Quantified Not AvailableNot AvailableConsuming polyphenols described by Phenol-Explorer entry 866 details
UrineExpected but not Quantified Not AvailableNot AvailableConsuming polyphenols described by Phenol-Explorer entry 866 details
UrineExpected but not Quantified Not AvailableNot AvailableConsuming polyphenols described by Phenol-Explorer entry 866 details
UrineExpected but not Quantified Not AvailableNot AvailableConsuming polyphenols described by Phenol-Explorer entry 866 details
UrineExpected but not Quantified Not AvailableNot AvailableConsuming polyphenols described by Phenol-Explorer entry 866 details
UrineExpected but not Quantified Not AvailableNot AvailableConsuming polyphenols described by Phenol-Explorer entry 866 details
UrineExpected but not Quantified Not AvailableNot AvailableConsuming polyphenols described by Phenol-Explorer entry 866 details
UrineExpected but not Quantified Not AvailableNot AvailableConsuming polyphenols described by Phenol-Explorer entry 866 details
UrineExpected but not Quantified Not AvailableNot AvailableConsuming polyphenols described by Phenol-Explorer entry 866 details
UrineDetected and Quantified0.06 (0.01-0.10) umol/mmol creatinineAdult (>18 years old)Both
Normal
details
UrineDetected but not Quantified Adult (>18 years old)Both
Normal
details
UrineDetected and Quantified0.00333 umol/mmol creatinineAdult (>18 years old)Both
Normal
details
UrineDetected and Quantified0.00590 +/- 0.0120 umol/mmol creatinineAdult (>18 years old)Both
Normal
details
UrineDetected and Quantified0.00327 (0.00275-0.00388) umol/mmol creatinineAdult (>18 years old)Not SpecifiedNormal
    • National Health a...
details
UrineDetected and Quantified0.00625 (0.00504-0.00775) umol/mmol creatinineChildren (1-13 years old)Not SpecifiedNormal
    • National Health a...
details
UrineDetected and Quantified1.560 +/- 1.780 umol/mmol creatinineAdult (>18 years old)Female
Normal
details
UrineDetected and Quantified0.00533 +/- 0.00600 umol/mmol creatinineAdult (>18 years old)Both
Normal
details
UrineDetected and Quantified0.00533 +/- 0.00533 umol/mmol creatinineAdult (>18 years old)Both
Normal
details
UrineDetected and Quantified0.440 +/- 0.807 umol/mmol creatinineAdult (>18 years old)Female
Normal
details
UrineDetected and Quantified0.0393 +/- 0.128 umol/mmol creatinineAdult (>18 years old)Female
Normal
details
UrineDetected and Quantified0.0574 +/- 0.198 umol/mmol creatinineAdult (>18 years old)Female
Normal
details
UrineDetected and Quantified0.000867 umol/mmol creatinineAdult (>18 years old)BothNormal details
UrineDetected and Quantified0.00686 umol/mmol creatinineChildren (1 - 13 years old)BothNormal details
UrineDetected and Quantified0.0167 +/- 0.0680 umol/mmol creatinineAdult (>18 years old)BothNormal details
UrineDetected and Quantified0.000413 umol/mmol creatinineAdult (>18 years old)FemaleNormal details
UrineDetected and Quantified0.00433 umol/mmol creatinineChildren (1 - 13 years old)FemaleNormal details
UrineDetected and Quantified0.00452 umol/mmol creatinineAdult (>18 years old)FemaleNormal details
UrineDetected and Quantified0.0124 umol/mmol creatinineAdult (>18 years old)FemaleNormal details
UrineDetected and Quantified0.0904 umol/mmol creatinineChildren (1-13 years old)FemaleNormal details
UrineDetected and Quantified0.283 umol/mmol creatinineChildren (1-13 years old)FemaleNormal details
UrineDetected and Quantified0.00288 +/- 0.0147 umol/mmol creatinineAdult (>18 years old)FemaleNormal details
UrineDetected and Quantified0.00320 +/- 0.0160 umol/mmol creatinineAdult (>18 years old)FemaleNormal details
UrineDetected and Quantified0.0112 +/- 0.0368 umol/mmol creatinineAdult (>18 years old)FemaleNormal details
UrineDetected and Quantified0.0144 +/- 0.0272 umol/mmol creatinineAdult (>18 years old)FemaleNormal details
UrineDetected and Quantified0.0320 +/- 0.0880 umol/mmol creatinineAdult (>18 years old)FemaleNormal details
UrineDetected and Quantified0.13 +/- 0.12 (0.0061-0.623) umol/mmol creatinineAdult (>18 years old)BothNormal details
Abnormal Concentrations
BiospecimenStatusValueAgeSexConditionReferenceDetails
UrineDetected and Quantified0 - 36.7 umol/mmol creatinineAdult (>18 years old)BothSoy consumption (ileostomies) details
Associated Disorders and Diseases
Disease References
Ileostomy
  1. Walsh KR, Haak SJ, Bohn T, Tian Q, Schwartz SJ, Failla ML: Isoflavonoid glucosides are deconjugated and absorbed in the small intestine of human subjects with ileostomies. Am J Clin Nutr. 2007 Apr;85(4):1050-6. [PubMed:17413104 ]
Associated OMIM IDsNone
DrugBank IDDB11674
Phenol Explorer Compound IDNot Available
FoodDB IDFDB021824
KNApSAcK IDC00009707
Chemspider ID82594
KEGG Compound IDC14131
BioCyc IDNot Available
BiGG IDNot Available
Wikipedia LinkEquol
METLIN IDNot Available
PubChem Compound91469
PDB IDNot Available
ChEBI ID428126
References
Synthesis ReferenceWang, Xiu-Ling; Hur, Hor-Gil; Lee, Je Hyeon; Kim, Ki Tae; Kim, Su-Il. Enantioselective synthesis of S-equol from dihydrodaidzein by a newly isolated anaerobic human intestinal bacterium. Applied and Environmental Microbiology (2005), 71(1), 214-219
Material Safety Data Sheet (MSDS)Download (PDF)
General References
  1. Moors S, Blaszkewicz M, Bolt HM, Degen GH: Simultaneous determination of daidzein, equol, genistein and bisphenol A in human urine by a fast and simple method using SPE and GC-MS. Mol Nutr Food Res. 2007 Jul;51(7):787-98. [PubMed:17579895 ]
  2. Yuan JP, Wang JH, Liu X: Metabolism of dietary soy isoflavones to equol by human intestinal microflora--implications for health. Mol Nutr Food Res. 2007 Jul;51(7):765-81. [PubMed:17579894 ]
  3. Setchell KD, Clerici C: Equol: history, chemistry, and formation. J Nutr. 2010 Jul;140(7):1355S-62S. doi: 10.3945/jn.109.119776. Epub 2010 Jun 2. [PubMed:20519412 ]
  4. Yokoyama S, Suzuki T: Isolation and characterization of a novel equol-producing bacterium from human feces. Biosci Biotechnol Biochem. 2008 Oct;72(10):2660-6. doi: 10.1271/bbb.80329. Epub 2008 Oct 7. [PubMed:18838805 ]