Chitosan is a linear polysaccharide composed of randomly distributed β-(1→4)-linked D-glucosamine (deacetylated units) and N-acetyl-D-glucosamine (acetylated units). It is a natural, biodegradable polymer derived from chitin, which is found in the exoskeletons of crustaceans such as shrimp, crabs, and lobsters, as well as in the cell walls of certain fungi like mushrooms (oyster mushroom & agaricus bisporus known as white button mushroom) and Aspergillus niger.

Chitosan is produced by deacetylating chitin, a process that involves treating it with an alkaline substance to remove acetyl groups. This results in a natural polycationic linear polysaccharide known for its versatility and numerous beneficial properties.

As a biomaterial, chitosan exhibits:

• Antibacterial Properties
• Antioxidant Properties
• Non-toxicity
• Low Allergenicity
• Biocompatibility
• Biodegradability

The U.S. Food and Drug Administration (FDA) classifies chitosan as “generally recognized as safe” (GRAS) (Casettari and Illum, 2014). It is the second most abundant natural polysaccharide after cellulose and finds applications across various industries due to its well-documented characteristics.