Chitin and Its Derivative Chitosan: Distribution in Nature, Applications, and Technology Research (A Review).

The present review highlights the chitin/chitosan as biopolymers that are promising for biomedical research development. Our goal was to assess the potential for practical use of these biopolymers and to summarize information on traditional and innovative technologies for their production and purification. The widespread occurrence of chitin and chitosan in nature as well as the unique chemical and biological properties of chitosan are reasons of growing interest in the use of the latter in several pharmaceutical fields. The main stages of chitin extraction and its further modification into chitosan are deproteinization, demineralization, deacetylation, and the main methods of chitosan purification are filtration, dialysis and reprecipitation. The profitability of the production of chitin/chitosan from crustaceans and edible mushrooms is approximately at the same level. The cost of mushroom products can be reduced by using agricultural or forestry waste as nutrient substrates. This makes the use of fungi as sources of chitin/chitosan in forested regions a rather promising issue.