Preparation and characterization of hydrophobic and hydrophilic amidated derivatives of carboxymethyl chitosan and carboxymethyl β-glucan.

Chitosan and β-glucan are substances that are very widely used in the pharmaceutical and food industries, medicine and other areas. These polysaccharides have immense significance in human metabolism. They are able to affect the levels of cholesterol and lipids. Chemical modification of these polysaccharides allows the support of these attributes. A main goal is to prepare a group of amide derivatives of carboxymethyl chitosan and carboxymethyl β-glucan to obtain a new group of polysaccharide derivatives and increase the benefits and attributes of these polysaccharides. The aim of carboxymethylation and subsequent two-step amidation is to achieve a high degree of substitution in the prepared derivatives. The amidation consisted methyl esterification followed by amino-de-alkoxylation with amidation reagents (n-alkylamines, hydrazine and hydroxylamine). The purity and substitution degree of the prepared derivatives were monitored by vibration spectroscopic methods (FTIR and FT Raman) and organic elemental analysis. The main, which was due to the presence of a secondary component (chitin) of polysaccharides, was the calculation of the substitution degree, which was based on the organic elemental analysis in combination with FTIR spectroscopy. These analytic methods confirmed the preparation of the substituted N-alkylamides, hydrazide and hydroxamic acid of carboxymethyl chitosan and carboxymethyl β-glucan. Published by Elsevier B.V.