Chitin

Chitin is a mucopolysacharide. It is the second most abundant biopolymer next to cellulose. Chitin was first isolated by braconnot in 1811 from mushrooms and was named “fungine”. A material identical to fungine was found in insects in 1821 by Odier and he named it as “chitine”.Chitin is a colourless hard substance found in the shells of cephalopods and in the internal structures of other invertebrates. Major sources of chitin are shell fish, krill, clams, oysters, squid and insects. Chitin is found in the cell walls of some fungi, molds and yeasts also. Zygometes also contain chitin. Fresh water bryozoans are able to produce colonies whose envelope is made up of chitin and protein in a noncalcified form allowing easy extraction of chitin.