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Spectroscopy and Photoreactivity of Trichochromes: Molecular Components of Pheomelanins†
Photochemistry and Photobiology, 2006The trichochromes are a class of small molecules present in pheomelanin (the red melanin) and absent in eumelanin (the black melanin). Herein trichochrome F (TF) and decarboxytrichochrome C (dTC) are examined. Both trichochromes are characterized by a visible absorption band, which is shown to be the result of overlapping transitions of the cis and ...
John D, Simon +6 more
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Pyrolysis-gas chromatography of pheomelanins
Journal of Analytical and Applied Pyrolysis, 1985Abstract Pheomelanins are the red-brown polymeric pigments found in the skin and hair of red-headed humans and are also responsible for the colour of red feathers and the fur of many animals. Natural pigments were isolated from red hen feathers and red human hair.
Jacek P. Dworzański, Maciej Debowski
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Brain size and the expression of pheomelanin‐based colour in birds
Journal of Evolutionary Biology, 2011AbstractEumelanin and pheomelanin are the most common vertebrate pigments. They generate different colours and are synthesized under different physiological conditions. While pheomelanogenesis requires high levels of a key intracellular antioxidant (glutathione, GSH), eumelanogenesis is inhibited by GSH.
Ismael Galvan, Anders Møller
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Artificial pheomelanin nanoparticles and their photo-sensitization properties
Journal of Photochemistry and Photobiology B: Biology, 2016Pheomelanin-type nanoparticles (PMNPs) were synthesized through a simple oxidative polymerization of 3,4-dihydroxyphenylalanine (DOPA) in the presence of cysteine by KMnO4. The synthesized PMNPs had a diameter of approximately 100nm, exhibited high dispersion stability in neutral water and various culture media and possessed similar morphology to ...
Jung, Pyo, Kuk-Youn, Ju, Jin-Kyu, Lee
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A review of therapies for hyperpigmentation modulating the synthesis of eumelanin to pheomelanin
Archives of Dermatological ResearchThere are significant psychosocial burdens in patients with hyperpigmentation, which emphasizes the importance of treatment. Current gold standard for treatment is hydroquinone; however, alternatives have been developed given the concern for side effects of hydroquinone.
Tasneem Mohammad +2 more
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The pheomelanin chromophore revisited.
2007Pheomelanin photochemistry is commonly regarded as reflecting the behavior of benzothiazine chromophores biogenetically derived from 5-S-cysteinyldopa. This notion, which has become a central dogma in pheomelanin research despite the lack of direct experimental support, has in part been built upon the identification many decades ago in pheomelanin ...
NAPOLITANO, ALESSANDRA +4 more
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Evidence for Eumelanin and Pheomelanin Producing Genotypes in the Arabian Horse
Journal of Heredity, 1988The ultrastructural imaging of melanocytes coupled with analyses to detect sulfur-containing melanosomes by energy-dispersive X-ray spectroscopy were used to test the hypothesis that the yellowish-red and black pigments found in Arabian horses result from pheomelanogenesis and eumelanogenesis, respectively.
C M, Woolf, J R, Swafford
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HPLC Analysis of Pheomelanin Degradation Products in Human Urine
Pigment Cell Research, 2003A sensitive and specific high performance liquid chromatography (HPLC) method was developed to quantify 4‐amino‐3‐hydroxyphenylalanine (4‐AHP) and 3‐amino‐4‐hydroxyphenylalanine (3‐AHP) in urine. In degradation studies of melanin pigment, 4‐AHP and 3‐AHP are derived from benzothiazine units of pheomelanin and pheomelanin‐related metabolites such as ...
Akihiko, Takasaki +5 more
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Gas chromatography–mass spectrometry analysis of pheomelanin degradation products
Journal of Chromatography A, 2009Melanoma is most rapidly increasing in the white population and people with pheomelanin skin type are at high risk to develop melanoma. However, little is known about the pheomelanin structure and function, and further elucidation of this melanin is therefore an important task.
Dzeneta Nezirević Dernroth
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Origins of Photodamage in Pheomelanin Constituents: Photochemistry of 4-Hydroxybenzothiazole
The Journal of Physical Chemistry A, 20184-Hydroxybenzothiazole (4-HBT) is a molecular constituent of pheomelanin-a polymeric skin centered pigment which acts as a natural photoprotector against harmful solar-UV radiation. Its molecular structure is therefore required to sustain a degree of photostability upon electronic excitation with UV irradiation.
Tolga N. V. Karsili +2 more
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