Biodegradation of chitin

The biodegradability of chitin and chitosan is mainly due to their susceptibility to enzymatic hydrolysis by lysozyme, a non-specific proteolytic enzyme present in all tissues of the human body. Lipase, an enzyme present in the saliva and in human gastric and pancreatic fluids, can also degrade chitosan [142]. The products of the enzymatic degradation of chitosan are non-toxic. The degree of acetylation, the molecular weight, the pH and even the method of preparation of chitosan affect biodegradation. 

Saimoto, H., Takamori, Y, Morimoto, M. et al. 1996. Biodegradation of chitin with vital components. Front. Biomed. Biotechnol. 3 251-259. 

The rate of in vivo biodegradation of subcutaneous implanted films was very high for chitin compared with that for deacetylated chitin. No tissue reaction was foimd with highly deacetylated chitosans, although they contained abundant primary amino groups [240]. 

Peculiar characteristics of chitins and chitosans are hemostatic action, anti-inflammatory effect, biodegradability, biocompatibihty, besides antimicrobial activity, retention of growth factors, release of glucosamine and M-acetylglucosamine monomers and oligomers, and stimulation of cellular activities [11,12,295-297]. 

More recently chitosan polymers which are derivatives of chitin materials have evoked interest due to their bioactivity and biodegradability. For example, N-carboxybutyl chitosan has been show to effectively promote wound healing (9). Acetate, and butyrate derivatives of chitosan have decreased blood clotting time significantly (10). 

Chitosan Chitosan is a nontoxic, biodegradable polymer obtained by hydrolysis of chitin, a natural polysaccharide that is a chief component of the crustacean exoskeleton. Unmodified chitosan is soluble in acidic media and has significant muco-adhesive properties. 

Chitin is a biodegradable material and undergoes biodegradation by enzymes such as lysozyme and chitinase. In vivo studies showed that lysozyme plays an important role in the degradation of chitin to produce... 

Chitin, a )5(l- 4)-linked iV-acetyl-D-glucosamine (GlcNAc) polysaccharide, is well-known for the excellent characters such as biodegradability and biocompatibility 36), Chitosan is a )ff(l- 4)-linked D-glucosamine (GlcN) polysaccharide, which is iV-deacetylated polysaccharide of chitin 41). Chitosan... 

Chitosan, a natural-based polymer obtained by alkaline deacetylation of chitin, is nontoxic, biocompatible, and biodegradable. These properties make chitosan a promising candidate for conventional and novel drug delivery systems. Because of the high affinity of chitosan for cell membranes, it has been used as a coating agent for liposome formulations [43-45]. 

Chitosan is a natural biopolymer that has many desirable characteristics as a scaffold or encapsulation material. It is a biodegradable, semicrystalline polysaccharide obtained by A-deacetylation of chitin, which is harvested from the exoskeleton of marine crustaceans. Chitosan is composed of glucosamine and A-acetyl glucosamine which are linked by glycosidic bonds. Being structurally similar to ECM components, chitosan provides cell-ECM interactions which guide cell behavior. 

Chitosan is obtained from the deacetylation of chitin, which is found in marine environments. Because it is insoluble in water, chitosan is dissolved in acidic solutions before being incorporated into biodegradable polymer films. It can also be plasticized with glycerol to obtain a kind of thermoplastic material like, for instance, plasticized starch (Epure, 2011]. 

Chitosan is a versatile polycationic biopolymer derived from alkaline deacetylation of chitin. It exhibits several valuable inherent properties such as antibacterial, antifungal, antiviral, antacidity, chelation, non-toxicity, and biodegradability as well as properties such as film formation. Further, due to its possession of hydroxyl and amino functional groups, chitosan can be fabricated to tailor... 

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