Melanin pigmentation

Heavily pigmented wools such as karakul require a more stringent approach, known as mordant bleaching, in which a metal salt is first appHed. The metal cations ate preferentially absorbed by the melanin pigment, where they subsequendy decompose hydrogen peroxide to produce highly aggressive hydroxyl free radicals, which then attack and bleach the melanin (114). 

Biochemistry and pharmacology of melanine pigments, indole derivatives 99MI14. 

Allomelanins — These are structurally different compounds containing little or no nitrogen. They are considered polymers of phenolic compounds like catechol. Fnngi prodnce melanin pigments, predominantly dihydroxyphenylalanine (DOPA)-melanin and dihydroxynaphthalene (DHN)-melanin. ... 

Melanosis Excessive pigmentation of the skin due to a disturbance in melanin pigmentation also called melanism. 

LOX-hydrogen peroxide system catalyzed the conversion of 5,6-dihydroxyindole and 5,6-dihydroxyindole-2-carboxylic acid, which are important intermediates of melanogenesis, into melanin pigments [47]. 

Several companies now produce sunglasses with melanin pigment embedded within the lenses the intention is for the commercial lens to mimic the way the eye blocks some wavelengths, i.e. forming natural sunglasses . The informative Website http // www.fcgmelanin.com has both history and science pages. 

Suryanarayanan TS et al.. Characterization of the melanin pigment of a cosmopolitan fungal endophyte, Mycol Res 108 974—978, 2004. 

Figure 3A and 3B Group of Field E.cordatum. Sections through immature ovarian tissues (3 A) and high power view of melanin pigment associated with degenerative change (3B). 

Also present in the epidermis are embedded macrophage-like Langerhans cells as well as pigmented melanocytes, cells with highly branched dendrites, which lie just above the basal stem cell layer. Each melanocyte contains hundreds of pigmented organelles called melanosomes. They contain not only the black or reddish melanin pigments but also the enzymes needed to form them (Chapter 25).n o... 

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