ABSTRACT
Chitin occurs in substantial quantities in the cell walls of numerous lower plants. Chitin and chitosan are commercially available in a variety of grades. Both chitin and chitosan are capable of forming complexes with metal ions, and this property has been utilized in Japan for water purification. The most important and economic source of chitin is crustaceans, which are gathered on a large scale as food. Chitosan slightly changes the water-holding capacity of the tofu gel structure. Chitosan exhibits antimicrobial activity against a range of foodborne microorganisms and as a result, was evaluated for its ability to serve as a potential natural food preservative. More than 2,000 edible species, such as crustaceans and insects that are utilized as food, serve as sources of chitin. Chitin and chitosan are not present in human tissues, but acetylglucosamine and chitobiose are found in glycoproteins and glycosaminoglycans.
