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Record Information
StatusDetected and Quantified
Creation Date2006-08-13 10:15:22 UTC
Update Date2020-04-23 20:56:20 UTC
Secondary Accession Numbers
  • HMDB04068
Metabolite Identification
Common NameMelanin
DescriptionDermal melanin is produced by melanocytes, which are found in the stratum basale of the epidermis. Although human beings generally possess a similar concentration of melanocytes in their skin, the melanocytes in some individuals and races more frequently or less frequently express the melanin-producing genes, thereby conferring a greater or lesser concentration of skin melanin. Some individual animals and humans have no or very little melanin in their bodies, which is a condition known as albinism. Higher eumelanin levels also can be a disadvantage, however, beyond a higher disposition toward vitamin D deficiency. Dark skin is a complicating factor in the laser removal of port-wine stains. Effective in treating fair skin, lasers generally are less successful in removing port-wine stains in Asians and people of African descent. Higher concentrations of melanin in darker-skinned individuals simply diffuse and absorb the laser radiation, inhibiting light absorption by the targeted tissue. Melanin similarly can complicate laser treatment of other dermatological conditions in people with darker skin. Under the microscope melanin is brown, non-refractile and finely granular with individual granules having a diameter of less than 800 nanometers. This differentiates melanin from common blood breakdown pigments which are larger, chunky and refractile and range in color from green to yellow or red-brown. In heavily pigmented lesions, dense aggregates of melanin can obscure histologic detail. A dilute solution of potassium permanganate is an effective melanin bleach. Pigments causing darkness in skin, hair, feathers, etc. They are irregular polymeric structures and are divided into three groups: allomelanins in the plant kingdom and eumelanins and phaeomelanins in the animal kingdom. Because melanin is an aggregate of smaller component molecules, there are a number of different types of melanin with differing proportions and bonding patterns of these component molecules. Both pheomelanin and eumelanin are found in human skin and hair, but eumelanin is the most abundant melanin in humans, as well as the form most likely to be deficient in albinism. Freckles and moles are formed where there is a localized concentration of melanin in the skin. They are highly associated with pale skin. Melanin is a biopolymer and a neuropeptide. In the early 1970s, John McGinness, Peter Corry, and Peter Proctor reported that melanin is a high-conductivity organic semiconductor (Science, vol 183, 853-855 (1974)). Studies revealed that melanin acted as a voltage-controlled solid-state threshold switch. Further, it emitting a flash of light electroluminescence when it switched.
Chemical FormulaC18H10N2O4
Average Molecular Weight318.283
Monoisotopic Molecular Weight318.064056818
IUPAC Name6,14-dimethyl-4,12-diazapentacyclo[²,⁵.0¹³,¹⁷.0⁹,¹⁸]octadeca-1(17),2,5,9(18),10,13-hexaene-7,8,15,16-tetrone
Traditional Namemelanin
CAS Registry Number8049-97-6
InChI Identifier
Chemical Taxonomy
Description belongs to the class of organic compounds known as anthracenes. These are organic compounds containing a system of three linearly fused benzene rings.
KingdomOrganic compounds
Super ClassBenzenoids
Sub ClassNot Available
Direct ParentAnthracenes
Alternative Parents
  • Anthracene
  • Indolequinone
  • Indole
  • Indole or derivatives
  • Isoindole
  • Isoindole or derivatives
  • Quinone
  • Vinylogous amide
  • Pyrrole
  • Heteroaromatic compound
  • Cyclic ketone
  • Organoheterocyclic compound
  • Azacycle
  • Organic nitrogen compound
  • Organooxygen compound
  • Organonitrogen compound
  • Hydrocarbon derivative
  • Organic oxide
  • Organopnictogen compound
  • Organic oxygen compound
  • Aromatic heteropolycyclic compound
Molecular FrameworkAromatic heteropolycyclic compounds
External DescriptorsNot Available
Physiological effect

Health effect:



Biological location:


Naturally occurring process:

Physical Properties
Experimental Properties
Melting PointNot AvailableNot Available
Boiling PointNot AvailableNot Available
Water SolubilityNot AvailableNot Available
LogPNot AvailableNot Available
Predicted Properties
Water Solubility0.31 g/LALOGPS
pKa (Strongest Acidic)12.65ChemAxon
pKa (Strongest Basic)1.34ChemAxon
Physiological Charge0ChemAxon
Hydrogen Acceptor Count6ChemAxon
Hydrogen Donor Count2ChemAxon
Polar Surface Area92.34 ŲChemAxon
Rotatable Bond Count0ChemAxon
Refractivity88.28 m³·mol⁻¹ChemAxon
Polarizability31.77 ųChemAxon
Number of Rings5ChemAxon
Rule of FiveYesChemAxon
Ghose FilterYesChemAxon
Veber's RuleNoChemAxon
MDDR-like RuleNoChemAxon
Spectrum TypeDescriptionSplash KeyView
Predicted GC-MSPredicted GC-MS Spectrum - GC-MS (Non-derivatized) - 70eV, Positivesplash10-00ku-0094000000-94704d5e412ed2489f17Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Positivesplash10-014i-0009000000-ca3bb49729033ec75f80Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Positivesplash10-014l-0089000000-bc7ad58775b231f90e84Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Positivesplash10-0229-0090000000-dc286795a5fc4078c357Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Negativesplash10-014i-0009000000-80dff8e14771680560aaSpectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Negativesplash10-014i-0019000000-395c4a7d06b442e4dcf1Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Negativesplash10-06ri-0091000000-760c7a558bb6db841316Spectrum
Biological Properties
Cellular Locations
  • Cytoplasm
Biospecimen Locations
  • Blood
Tissue Locations
  • Adrenal Gland
  • Adrenal Medulla
  • Bladder
  • Epidermis
  • Fibroblasts
  • Hair
  • Neuron
  • Spleen
  • Thyroid Gland
Normal Concentrations
BloodDetected and Quantified5345 +/- 318 uMAdult (>18 years old)Both
BloodDetected and Quantified5030.0 +/- 314.0 uMAdult (>18 years old)Both
Abnormal Concentrations
BloodDetected and Quantified8551 +/- 1194 uMAdult (>18 years old)Both
Chronic renal failure
Associated Disorders and Diseases
Disease References
Chronic renal failure
  1. Hegedus ZL, Frank HA, Steinman TI, Altschule MD, Nayak U: Elevated levels of plasma lipofuscins in patients with chronic renal failure. Arch Int Physiol Biochim. 1988 Dec;96(5):211-21. [PubMed:2474282 ]
Associated OMIM IDsNone
DrugBank IDNot Available
Phenol Explorer Compound IDNot Available
FooDB IDFDB023298
KNApSAcK IDNot Available
Chemspider ID4884931
KEGG Compound IDC05606
BioCyc IDNot Available
BiGG ID46115
Wikipedia LinkMelanin
PubChem Compound6325610
PDB IDNot Available
ChEBI ID89634
Food Biomarker OntologyNot Available
Synthesis ReferenceNot Available
Material Safety Data Sheet (MSDS)Not Available
General References
  1. Pugh ND, Balachandran P, Lata H, Dayan FE, Joshi V, Bedir E, Makino T, Moraes R, Khan I, Pasco DS: Melanin: dietary mucosal immune modulator from Echinacea and other botanical supplements. Int Immunopharmacol. 2005 Apr;5(4):637-47. [PubMed:15710333 ]
  2. Borges CR, Roberts JC, Wilkins DG, Rollins DE: Relationship of melanin degradation products to actual melanin content: application to human hair. Anal Biochem. 2001 Mar 1;290(1):116-25. [PubMed:11180945 ]
  3. Alaluf S, Atkins D, Barrett K, Blount M, Carter N, Heath A: The impact of epidermal melanin on objective measurements of human skin colour. Pigment Cell Res. 2002 Apr;15(2):119-26. [PubMed:11936269 ]
  4. Wenczl E, Van der Schans GP, Roza L, Kolb RM, Timmerman AJ, Smit NP, Pavel S, Schothorst AA: (Pheo)melanin photosensitizes UVA-induced DNA damage in cultured human melanocytes. J Invest Dermatol. 1998 Oct;111(4):678-82. [PubMed:9764853 ]
  5. Nielsen KP, Zhao L, Stamnes JJ, Stamnes K, Moan J: The importance of the depth distribution of melanin in skin for DNA protection and other photobiological processes. J Photochem Photobiol B. 2006 Mar 1;82(3):194-8. Epub 2006 Jan 4. [PubMed:16388960 ]
  6. Watanabe T, Tamura A, Yoshimura Y, Nakazawa H: Determination of melanin in human hair by photoacoustic spectroscopy. Anal Biochem. 1997 Dec 15;254(2):267-71. [PubMed:9417788 ]
  7. Claridge E, Cotton S, Hall P, Moncrieff M: From colour to tissue histology: Physics-based interpretation of images of pigmented skin lesions. Med Image Anal. 2003 Dec;7(4):489-502. [PubMed:14561553 ]
  8. Schmidt R, Krien P, Regnier M: The use of diethylaminoethyl-cellulose-membrane filters in a bioassay to quantify melanin synthesis. Anal Biochem. 1996 Mar 15;235(2):113-8. [PubMed:8833318 ]
  9. Lu H, Edwards C, Gaskell S, Pearse A, Marks R: Melanin content and distribution in the surface corneocyte with skin phototypes. Br J Dermatol. 1996 Aug;135(2):263-7. [PubMed:8881670 ]
  10. Kronstrand R, Forstberg-Peterson S, Kagedal B, Ahlner J, Larson G: Codeine concentration in hair after oral administration is dependent on melanin content. Clin Chem. 1999 Sep;45(9):1485-94. [PubMed:10471651 ]
  11. Bartosik J, Wulf HC, Kobayasi T: Melanin and melanosome complexes in long standing stable vitiligo--an ultrastructural study. Eur J Dermatol. 1998 Mar;8(2):95-7. [PubMed:9649719 ]
  12. Svensson SP, Lindgren S, Powell W, Green H: Melanin inhibits cytotoxic effects of doxorubicin and daunorubicin in MOLT 4 cells. Pigment Cell Res. 2003 Aug;16(4):351-4. [PubMed:12859618 ]
  13. Dwyer T, Muller HK, Blizzard L, Ashbolt R, Phillips G: The use of spectrophotometry to estimate melanin density in Caucasians. Cancer Epidemiol Biomarkers Prev. 1998 Mar;7(3):203-6. [PubMed:9521433 ]
  14. Shimada M, Yamada Y, Itoh M, Yatagai T: Melanin and blood concentration in human skin studied by multiple regression analysis: experiments. Phys Med Biol. 2001 Sep;46(9):2385-95. [PubMed:11580175 ]
  15. Yamashita T, Kuwahara T, Gonzalez S, Takahashi M: Non-invasive visualization of melanin and melanocytes by reflectance-mode confocal microscopy. J Invest Dermatol. 2005 Jan;124(1):235-40. [PubMed:15654979 ]
  16. Huang Z, Zeng H, Hamzavi I, Alajlan A, Tan E, McLean DI, Lui H: Cutaneous melanin exhibiting fluorescence emission under near-infrared light excitation. J Biomed Opt. 2006 May-Jun;11(3):34010. [PubMed:16822060 ]
  17. Eng HL, Chen WJ: Melanin-producing medullary carcinoma of the thyroid gland. Arch Pathol Lab Med. 1989 Apr;113(4):377-80. [PubMed:2705868 ]
  18. Mammone T, Marenus K, Muizzuddin N, Maes D: Evidence and utility of melanin degrading enzymes. J Cosmet Sci. 2004 Jan-Feb;55(1):116-7. [PubMed:15037924 ]
  19. Shimada M, Yamada Y, Itoh M, Yatagai T: Melanin and blood concentration in a human skin model studied by multiple regression analysis: assessment by Monte Carlo simulation. Phys Med Biol. 2001 Sep;46(9):2397-406. [PubMed:11580176 ]
  20. Nishidate I, Aizu Y, Mishina H: Depth visualization of a local blood region in skin tissue by use of diffuse reflectance images. Opt Lett. 2005 Aug 15;30(16):2128-30. [PubMed:16127932 ]


General function:
Involved in copper ion binding
Specific function:
Oxidation of 5,6-dihydroxyindole-2-carboxylic acid (DHICA) into indole-5,6-quinone-2-carboxylic acid. May regulate or influence the type of melanin synthesized
Gene Name:
Uniprot ID:
Molecular weight:
General function:
Involved in arsenite transmembrane transporter activity
Specific function:
Could be involved in the transport of tyrosine, the precursor to melanin synthesis, within the melanocyte. Regulates the pH of melanosome and the melanosome maturation. One of the components of the mammalian pigmentary system. Seems to regulate the post-translational processing of tyrosinase, which catalyzes the limiting reaction in melanin synthesis. May serve as a key control point at which ethnic skin color variation is determined. Major determinant of brown and/or blue eye color
Gene Name:
Uniprot ID:
Molecular weight: