Chitosan and its functional derivatives for nutraceutical delivery: Focus on quaternized, hydrochloride, and carboxymethyl forms

Background

Chitosan is a natural cationic polysaccharide valued for its excellent biocompatibility, biodegradability, low toxicity, and inherent bioactivity, rendering it a promising candidate for nutraceutical delivery systems. However, its poor solubility under neutral and alkaline conditions significantly limits its broader applications.

Scope and approach

This review provides a comprehensive analysis of the structural characteristics, preparation methods, and functional properties of chitosan derivatives, with emphasis on three prominent types: quaternized chitosan (QCS), chitosan hydrochloride (CHC), and carboxymethyl chitosan (CMC). Their potential application in the delivery of natural bioactive nutraceuticals are valuated, particularly regarding their roles in enhancing bioavailability, improving stability, and enabling targeted release. Additionally, the review discusses the challenges and future prospects of for modified chitosan in food science and technology.

Key findings and conclusions

Chitosan with a high degree of deacetylation and low molecular weight exhibits enhanced solubility due to its increased cationic charge. QCS demonstrates strong mucoadhesive and antimicrobial properties, coupled with broad pH solubility, making it particularly effective for encapsulating polyphenols and bioactive peptides. CHC is highly soluble in acidic environments, thereby facilitating the efficient delivery of pigment compounds. Meanwhile, CMC, featuring a negative charge and pH -sensitive properties, supports controlled release profiles and significantly enhances the stability of lipophilic or unstable nutrients. Collectively, these attributes underscore the substantial potential of chitosan derivatives as advanced carrier systems for natural bioactive nutraceuticals in food-based applications.