Chitin
1.The introduction of chitin
1.1 The discovery process
◆ In
1811,Henri Braconnot found the chitin for the first time, named "fungine“. ◆ In 1823 ,Odier discovered the same material in insects and plants, called "chitine". In 1843 ,Lassaingne prove the existence of nitrogen in chitin . ◆ The later research showed that chitin is composed of n-acetyl glucosamine polycondensation From chitin was discovered in 1811 to study the structure clearly, it takes nearly 100 years.
Chitin
other areas
environmental protection
2.The sources and distribution of chitin
Chitin is widely exist in lower plants, fungi and aquatic algae cells, arthropods insects like crustaceans of shrimp(虾), crab（蟹） and mollusks of shellfish （贝类）, and cartilage（软骨） of cephalopods, and higher plant cell walls. Chitin is the main composition of arthropod exoskeletons, such as shrimp, crab, content is 20% 30%, the higher can up to 58% to 58%.
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some mollusks, such as snails(蜗牛), oysters(牡蛎) squid(乌贼), the content of chitin is 3% to 26%.
▼ In
is important components of the cell walls of fungi such as ascomycetes(子囊菌) , basidiomycetes(担子菌) and algae bacteria. ▼ In the joints, hoof, foot part of the animal and animal muscle and bone joint chitin qualitative both exist. Therefore chitin not only is the necessary element of the many invertebrates, also exist in many vertebrates.
▼ Chitin
3.The Structure of chitin
Chitin is a kind of polysaccharide made up of N-acetyl - 2 – amino- 2 – deoxy - D – glucose which connected by the β - 1,4 glycosidic bond.
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1.2 The chitin for nowadays Today we know that the chitin(几丁质， 甲壳素，甲壳质), after cellulose, is the second most abundant natural polymer. It does not dissolve in water, and in the vast majority of the solvent in a difficult state, is now known, chitin can only be dissolved in a solvent, such as the six fluoride isopropyl alcohol（六氟异丙醇）, the six fluorideacetone hydrates（六氟丙酮水化物）, some chlorohydrin(氯醇) and concentrated acid, etc.
It has good biocompatibility(生物相容性), biodegradable and absorption and antimicrobial and the ability to promote wound healing and low immune tolerance. As a natural macromolecular material with excellent properties in the development and application of chitin resources research has received the extensive Chemical attention of scholars both at food industry industry home and abroad.
Structurally, chitin chemical structure similar to natural cellulose, the difference is cellulose(纤维素) on 2 is hydroxyl, chitin on 2 is acetyl amino and chitosan(壳聚糖) are two amino. Chitin taken off for more than 55% of N acetyl groups may call it the chitosan