Preliminary insights into chitosan disaggregation by high hydrostatic pressure

Chitosan, a biological polysaccharide derived from the very abundant biopolymer, chitin, has been submitted to high hydrostatic pressure treatments to improve its properties. Despite its abundance, low price and utility potential, the low solubility and reactivity of chitin impairs its industrial use. Chitosan is the result of its partial deacetylation, to increase its solubility, creating positive charges along its chain when in aqueous acidic media.Chitosan has been reported to have a strong aggregation tendency and still a low solubility. Pressure treatments at moderate pressure levels, temperatures and processing times have been found to yield more amenable products, where its much lower DLS hydrodynamic radius and polydispersity suggest a chain disentanglement and a reduced aggregation degree. The evidence of chitosan aggregation reduction and possible mechanisms are discussed.