IL versus DES: Impact on chitin pretreatment to afford high quality and highly functionalizable chitosan. (1st October 2021)

• Record Type: Journal Article
• Authors: Huet, Gaël; Hadad, Caroline; González-Domínguez, Jose M.; Courty, Matthieu; Jamali, Arash; Cailleu, Dominique; van Nhien, Albert Nguyen
• Is Part Of: Carbohydrate polymers. Volume 269(2021)
• Publication Date: 2021-10-01
• Subjects: Chitin -- Chitosan -- Room temperature ionic liquid -- Deep eutectic solvent -- Functionalization -- Fatty acid; Polysaccharides -- Periodicals; Polysaccharides -- Periodicals; Polysaccharides -- Périodiques; Electronic journals; 547.78
• DOI: 10.1016/j.carbpol.2021.118332
• Languages: English
• ISSNs: 0144-8617

Abstract

Abstract: Chitin is mainly extracted from crustaceans, but this resource is seasonally dependent and can represent a major drawback to satisfy the traceability criterion for high valuable applications. Insect resources are valuable alternatives due to their lower mineral content. However, the deacetylation of chitin into chitosan is still an expensive process. Therefore, we herein compare the impact of both DES/IL-pretreatments on the efficiency of the chemical deacetylation of chitin carried out over two insect sources ( Bombyx eri, BE and Hermetia illucens, HI) and shrimp shells (S). The results showed that chitosans obtained from IL-pretreated chitins from BE larva, present lower acetylation degrees (13–17%) than DES-pretreated samples (18–27%). A selective N -acylation reaction with oleic acid has also been performed on the purest and most deacetylated chitosans leading to high substitution degrees (up to 27%). The overall approach validates the proper chitin source and processing methodology to achieve high quality and highly functionalizable chitosan. Graphical abstract: Unlabelled Image Highlights: Raw biomasses and pure chitins from two insect sources were pretreated with IL and DES. IL-pretreatment of pure chitins led to amorphization and lower CrI were obtained. DES-pretreatment of pure chitins removed the amorphous regions leading to higher CrI. IL-pretreated chitins from BE larva present lower acetylation degrees (13–17%) than DES-pretreated samples (18–27%). Selective N -acylation performed on chitosans led to high substitution degrees (up to 27%).