Isolation and Characterization of Melanin from the Commercially Available Edible Mushrooms

Melanin is a natural pigment with a wide range of biological and biomedical applications.It is currently a subject of great research interest.Its versatile uses span various fields and make it highly desirable.Melanin from the plant sources are difficult to separate from other phenolic compounds.Melanin from the animal derived sources is often contaminated with proteins, in the present investigation, three commercially available edible mushrooms, namely Lentinula edodes, Agaricus bisporus and Pleurotus ostreatus were used to isolate melanin pigment.The melanin pigment was successfully extracted from Lentinus edodes by hot alkali treatment followed by acid precipitation.Various tests carried out on the isolated pigment showed similar properties to melanin, insolubility in both water and organic solvents, while it is soluble in alkali.Examination of the pigment particles by scanning electron microscopy revealed that they have a spherical shape with a size of 20-50 nm.Fourier transform infrared spectroscopy (FTIR) and nuclear magnetic resonance (NMR) spectroscopy were used for further characterization.These methods make possible a detailed analysis of the molecular structure of the pigment.