Microbial production of coloured azaphilone metabolites

Azaphilones, Fungal secondary metabolites of the pyranequinone structure, r eact with ammonia yielding vinylogous 4-pyridones. The pigments also react with amines, such as proteins, amino acids and nucleic acids, to form water -soluble pigments. Their most remarkable and valuable properties include th e natural origin, yellow-red spectra, thermostability (in comparison with o ther natural red pigments), and easy derivatization. So far, they have been identified in a variety of fungal sources. Of the microorganisms tested, o nly genera Monascus, Penicillium and Chaetomium are good producers of azaph ilone pigments. However, similar structures were also identified in Aspergi llus ustus, Cochliobolus lunata, Talaromyces sp. and Emericella falconensis . The microorganisms could be a promising source of the new group of natura l pigments for food and cosmetic industry.