Crustaceans exoskeleton

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. 

Kumari SS, Skinner DM (1993) Proteins of crustacean exoskeleton II immunological evidence for their relatedness to cuticular proteins of two insects. J Exp Zool 265 195-210... 

Chitin—a polysaccharide polymer composed of N-acetyl-D-glucos-amine found in algae, arthropod and crustacean exoskeletons, fungal cell walls, and most protozoa. 

Raabe, D., Sachs, C., Romano, P. The crustacean exoskeleton as an example of a structurally and mechanically graded biological nanocomposite material. Acta Mater. 2005, 53,4281-4292. 

Chitin, identical in linkage to cellulose but composed of fV-acetylglucosamine instead of glucose, is the major structural component of insect and crustacean exoskeletons as well as a cell wall component of molds and fiingi. The structural comments regarding cellulose also apply generally to chitin, especially in terms of stability. Less industrial development has been done with this polymer, in part because shrimp shells may present a more difficult starting material than trees. 

Glucose molecules can link together into chains, with each ring tethered to the next by a bridging oxygen atom. In one form, this is cellulose, the stiff material that gives the stalks of plants and the trunks of trees their structural strength. Chitin, a variation on cellulose, is an even stiffen material that forms the exoskeletons of crustaceans such as crabs and lobsters. 

Chitin, a polymer of N-acetylglucosamine, is present in large amounts in the exoskeletons of crustaceans and other arthropods and is a major marine biopolymer 16). Its availability is, however, limited to byproducts from seafood industries (76). 

Chitin is a polysaccharide similar to cellulose except that the OH at C-2 is replaced by an acetamido group (CH3CONH). Chitin is the main component of the hard external covering (exoskeleton) of crustaceans such as lobsters, crabs, and shrimp. Like cellulose, the processing of chitin into polymeric products is limited by its insolubility and decomposition without melting. The availability in huge quantities has encouraged many attempts to find commercial applications of chitin, but very few have been found to be economically feasible. 

Greenland 1978-93 Molluscs, 5 species soft parts Crustaceans, 6 species Exoskeleton Muscle... 

Chitosan Chitosan has a molecular structure similar to cellulose. This material is produced from chitin, which is widely found in the exoskeleton of shellfish and crustaceans. Chitin is the second most abundant natural biopolymer after cellulose. Chitosan is a good adsorbent for all heavy metals. It has been estimated that chitosan can be produced from shellfish and crustaceans at a market price of 15.43 /kg. 

The exoskeleton of the crab and other crustaceans is primarily composed of a substance called chitin. This is a giant molecule made up of fundamental units of N-acetyglucosamine strung together like links in a chain. Chitin is abundantly available, thanks to a crab and lobster industry dedicated to making it easier for us to consume their products by removing the... 

Chitin Homo- (j81—>4)GlcNAc Very large Structural in insects, spiders, crustaceans, gives rigidity and strength to exoskeletons... 

Plant structural material is the polysaccharide cellulose, which is a linear p (1 —> 4) linked polymer. Some structural polysaccharides incorporate nitrogen into their molecular structure an example is chitin, the material which comprises the hard exoskeletons of insects and crustaceans. Chitin is a cellulose derivative wherein the OH at C-2 is replaced by an acetylated amino group (—NHCOCH3). Microbial polysaccharides, of which the capsular or extracellular (exopolysaccharides) are probably the most important class, show more diversity both in monomer units and the nature of their linkages. 

Chitin is a polysaccharide constituted of N -acctylglucosamine, which forms a hard, semitransparent biomaterial found throughout the natural world. Chitin is the main component of the exoskeletons of crabs, lobsters and shrimps. Chitin is also found also in insects (e.g. ants, beetles and butterflies), and cephalopods (e.g. squids and octopuses) and even in fungi. Nevertheless, the industrial source of chitin is mainly crustaceans. 

Chitin, which is the structural component of the exoskeleton of invertebrates such as crustaceans, insects, and spiders, resembles cellulose with the exception that the hydroxy groups on carbon 2 are replaced by acetylamino groups. 

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