Haematin (also known as hematin, ferriheme, hematosin, hydroxyhemin, oxyheme, phenodin, or oxyhemochromogen) is a dark bluish or brownish pigment containing iron in the ferric state, obtained by the oxidation of haem. This is not to be confused with haematein, which is a dark purple water-insoluble crystalline substance obtained from logwood and used as an indicator and biological stain.
Haematin inhibits the synthesis of porphyrin, and stimulates the synthesis of globin. It is a component of cytochromes and peroxidases, and is also used as a reagent.
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Haematin Wikipedia(Text) CC BY-SA