Chitosan biodegradation

Genipin-crosslinked collagen-chitosan biodegradable porous scaffolds... 

Gooday, G. W. 1990. Physiology of microbial degradation of chitin and chitosan. Biodegradation 1 177-190. 

Pitak N, Rakshit SK (2011) Physical and antimicrobial proptaties of banana flour/chitosan biodegradable and self sealing films used for preserving fresh-cut vegetables. LWT—Food Sci Technol 44 2310-2315... 

The latest advances in bio-based polymers are beyond the scope of this chapter, however, the reader can refer to a number of reviews [4-6] on the synthesis and applications of biopolymers. Instead in this chapter, we will review latest advances in liquid repellent surfaces and materials based on biopolymers staring with cellulose, other polysaccharides such as starch and chitosan, biodegradable polyesters, and plant waxes. It is hoped that this chapter will encourage researchers actively engaged in conventional liquid repellent technologies to explore new techniques and materials based on biodegradable polymers. 

Attenuated total reflection (ATR) spectra of rice starch film, chitosan film and typical rice starch-chitosan biodegradable film with the ratio of rice starch to chitosan of 1 1. Reprinted from Bourtoom and Chinnan, 2008, with permission from Elsevier. 

Bonilla J, Fortunati E, Atares L, Chlralt A, Kemy JM (2014). Physical, structural and antimicrobial properties of poly vinyl alcohol-chitosan biodegradable films. Food Hydrocolloid, 35,463-470. 

Other blends such as polyhydroxyalkanoates (PHA) with cellulose acetate (208), PHA with polycaprolactone (209), poly(lactic acid) with poly(ethylene glycol) (210), chitosan and cellulose (211), poly(lactic acid) with inorganic fillers (212), and PHA and aUphatic polyesters with inorganics (213) are receiving attention. The different blending compositions seem to be limited only by the number of polymers available and the compatibiUty of the components. The latter blends, with all natural or biodegradable components, appear to afford the best approach for future research as property balance and biodegradabihty is attempted. Starch and additives have been evaluated ia detail from the perspective of stmcture and compatibiUty with starch (214). 

Recently, however, we have embarked on a programme aimed at developing biodegradable and renewable support materials based on the very abundant sources of biomass such as starch, chitosan and cellulose, in addition to the inorganic materials mentioned above. 

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). 

Similar structures were later employed to create original dendronized polymers 485 and 486, based on a chitosan backbone and using such sialodendrons as 484 (Fig. 50).328 Chitosan itself is nontoxic, biodegradable, and has widespread biological activities, but major intrinsic drawbacks such as low solubility in both organic solvents and water have hampered its development as a bioactive polymer. Thus, the synthesis of water-soluble... 

Chenite A, Chaput C, Wang D et al (2000) Novel injectable neutral solutions of chitosan form biodegradable gels in situ. Biomaterials 21 2155-2161... 

Biodegradable polymers, both synthetic and natural, have gained more attention as carriers because of their biocompatibility and biodegradability and therewith the low impact on the environment. Examples of biodegradable polymers are synthetic polymers, such as polyesters, poly(orfho-esters), polyanhydrides and polyphosphazenes, and natural polymers, like polysaccharides such as chitosan, hyaluronic acid and alginates. 

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