Chitosan and Chitooligosaccharides

Chitosan is a naturally occurring biopolymer isolated by the N-deacetylation of chitin. It is the main constituent of the exoskeletons of marine crustaceans, including shrimp and crab. Recently, Chitosan is of a special interest for applications in the 

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S. Hu, C. Jou, M. Yang, Protein adsorption, fibroblast activity and antibacterial propaties of poly (3-hydroxybutyric add-co-3-hydroxyvaleric add) grafted with chitosan and chitooligosaccharide after immobilized with hyaluronic add. Biomaterials 24 (16) (2003) 2685-2693. 

Vander, P, Varum, K.M., Domard, A., Gueddari, N.E.E., and Moerschbacher, B.M. 1998. Comparison of the ability of partially V-acetylated chitosans and chitooligosaccharides to elicit resistance reactions in wheat... 

Hu SG, Jou CH, Yang MC. Antibacterial and biodegradable properties of polyhydroxy-alkanoates grafted with chitosan and chitooligosaccharides via ozone treatment. J Appl Polym Sci 2003 88 2797-2803. 

Hydroxybutyric acid-hydroxyvaleric acid copolymer membranes were treated with ozone and grafted with acrylic acid. The membranes were further grafted with chitosan or chitooligosaccharide via esterification and immobilised with hyalmonic acid. Antibacterial activities were investigated. Surface properties were characterised using a water contact angle goniometer. 26 refs. 

Cabrera, J. C. and P. van Cntsem. 2005. Preparation of chitooligosaccharides with degree of polymerization higher than 6 by acid or enzymatic degradation of chitosan. Biochem. Eng. J. 25 165-172. 

Nagae, S., M. Izume, S. Nishimura, H. Kawagishi, and A Ohtakara. 1992. Preparation of chitooligosaccharide-alditols by hydrogenation with ruthenium catalyst. In Advances in Chitin and Chitosan, eds. C. J. Brine, P. A. Sandford, and J. P. Zikakis, pp. 378-384. London, U.K. Elsevier. 

Chitosan also has in vivo stimulatory effect on both nitric oxide production and chemotaxis, and modulates the peroxide production. Chitooligosaccharides (COS) enhanced the migration of the mouse peritoneal macrophages into inflammatory area (Okamoto et al. 2003, Mori et al. 2005, Moon et al. 2007). Yoon et al. (2007) reported that lipopolysaccharide (LPS)-stimulated TNF-a and IL-6 secretion was significantly inhibited in the presence of chitosan oligosaccharide in RAW 264.7 cells. These results suggested that chitosan oligosaccharide may have the anti-inflanunatory effect via the stimulus of TNF-a in the LPS-stimulated inflammation. 

Antioxidative Activity of Chitosan, Chitooligosaccharides, and Their Derivatives.242... 

Although chitosan is known to have various biological properties, it is poorly soluble in acidic medium of above pH 6.5. Therefore, many studies on chitosan have attracted interest for converting it to chitooligosaccharides (COSs). The COSs have lower viscosity and relatively small molecular size that makes them water-soluble and readily absorbable in the in vivo systans. They also possess... 

Park, P. J., Je, J. Y, and Kim, S. K. 2003. Angiotensin I converting enzyme (ACE) inhibitory activity of hetero-chitooligosaccharides prepared from partially different deacetylated chitosans. J. Agric. Food Chem. 51 4930 934. 

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