Chitosan is a linear aminopolysaccharide obtained by deacetylation of chitin. Deacetylated chitin is called chitosan. The degree of deacetylation is defined as the ratio of the number of amino groups to the number of acetylamino groups. At the end of the deacetylation process, chitin can approach chitosan up to 70-95% deacetylation degree. Chitosan is a linear polysaccharide consisting of ß(1,4)-linked D-gucosamino units obtained by deacetylation of chitin in alcoholic medium and has an average molecular weight between 3.200-2.000.000 g/mol.