Form of chitin

Chitosan is the deacetylated form of chitin. Chitin is the second most occurring polymer in nature behind cellulose. Chitosan is an... 

Chitin is the 2-acetamido derivative of cellulose and serves as the fibrous component of skeletal tissues in many lower animals. At least two polymorphic forms of chitin have been recognized, (26) of which the a- and 0-forms are the best characterized. The unit cells and space groups of a- and 0-chitins are given in Table 1. Both have approximately the same fiber repeat as cellulose, and apparently have the same 2j helical conformation. 

Svitil, A. L., S. M. N. Chadhain, J. A. Moore, and D. L. Kirchman. 1997. Chitin degradation proteins produced by the marine bacterium Vibrio harveyi growing on different forms of chitin. Applied Environmental Microbiology 63 408-413. 

Secondly, the deacetylated form of chitin, chitosan, does not induce phytoalexin formation in the rice system but is active in other plant culture systems [99]. Glucan elicitors induce phytoalexins in legumes (soybean, chickpea, bean, alfalfa, pea) and solanaceous sp. (potato, sweet pepper) [100]. However, anthraquinone biosynthesis was stimulated in Morinda citrifolia by both chitin and chitosan. The degree of acetylation was found to be important in inducing defense responses. During the first few days of incubation after adding elicitor,... 

Various forms of chitin-based products are available for medical applications, such as finely divided powder, nonwoven fabrics, porous beads, lyophilized soft fleeces or gels, gauges, laminated sheets, and transparent films. Water-soluble derivatives of chitin in isotonic saline can be administered intramuscularly or intravenously. Certainly, there is considerable biochemical evidence linking NAG with the metabolism of the hexamines, which are assumed to originate and cross-link wound collagen. 

Chitosan is a 3-1,4-linked glucosamine polymer and partially deacetylated form of chitin. Naturally, it is present as a major component of the Zygomycete cell walls and usually obtained by artificial deacetylation of chitin. Chitosanase (EC 3.2.1.99) is a hydrolytic enzyme which catalyzes the breakdown of chitosan into glucosamine oligomers (1). It has been isolated from several microorganisms inchidmg Streptomyces (2), Pseudomonas (3), Bacillus (4), Penicillium (5) and Fusarium (6). 

A third regulatory molecule may also exist. In Mucorrouxiithere is a larger protein which specifically inhibits the activated form of chitin synthetase itself, while leaving the activating factor fully functional. 

Chitosan, a natural cationic linear polymer obtained from chitin, has been proved to be biodegradable, biocompatible, non-antigenic and non-toxic. It is composed of copolymers of (3-(l-4)-glucosamine and randomly located N-acetyl-D-glucosamine and can be a fully or partially deacetylated form of chitin. The number of amine groups in chitosan plays a major role in... 

Developing defined lower molecular weights or oligomeric forms of chitin and chitosan as fnture application potential... 

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