Chitosan - Wikipedia. Chitosan. Names. Other names. Poliglusam; Deacetylchitin; Poly- (D)glucosamine; BC; Chitopearl; Chitopharm; Flonac; Kytex. Identifiers. Chem. Spider. ECHA Info. Card. 10. 0. 1. 22. In. Ch. I=1. S/C5. H1. 03. N9. O3. 9/c. ![]() H,2- 1. 0,5. 7- 6. H2,1. H3,(H,6. 5,8. YKey: FLASNYPZGWUPSU- SICDJOISSA- N YIn. Ch. I=1/C5. 6H1. 03. N9. O3. 9/c. 1- 8. H,2- 1. 0,5. 7- 6. ![]() H2,1. H3,(H,6. 5,8. Key: FLASNYPZGWUPSU- SICDJOISBYCOC(=O)N. It is made by treating the chitin shells of shrimp and other crustaceans with an alkaline substance, like sodium hydroxide. Chitosan has a number of commercial and possible biomedical uses. It can be used in agriculture as a seed treatment and biopesticide, helping plants to fight off fungal infections. In winemaking, it can be used as a fining agent, also helping to prevent spoilage. In industry, it can be used in a self- healing polyurethanepaint coating. In medicine, it may be useful in bandages to reduce bleeding and as an antibacterial agent; it can also be used to help deliver drugs through the skin. Time: 11:39:13 EST (16:39:13 UTC) Date: 28 January 1986; 31 years ago () Location: Atlantic Ocean, off the coast of Florida: Outcome: Grounding of the Space Shuttle.USA Retreats There are those, I know, who will say that the liberation of humanity, the freedom of man and mind, is nothing but a dream. They are right. Stan was born in St. Paul, Minnesota and was raised in Spokane, Washington. As a young boy he was fascinated with and inspired by airplanes and spent much time. Plan your child’s summer care, enrichment opportunities, and old-fashioned, outdoor fun with help from our ultimate guide to summer camps and classes in Little Rock. Destinations 10 Most Rugged Trail Running Spots in the U.S. From a rugged, ultra-muddy backcountry path in New Hampshire, to a lung piercing, single-track in New. More controversially, chitosan has been asserted to have use in limiting fat absorption, which would make it useful for dieting, but there is evidence against this. Other uses of chitosan that have been researched include use as a soluble dietary fiber. Manufacture and properties. The degree of deacetylation (%DD) can be determined by NMR spectroscopy, and the %DD in commercial chitosans ranges from 6. On average, the molecular weight of commercially produced chitosan is between 3. Daltons. A common method for the synthesis of chitosan is the deacetylation of chitin using sodium hydroxide in excess as a reagent and water as a solvent. ![]() The reaction occurs in two stages under first- order kinetic control. Activation energy for the first step is higher than the second; its value is an estimated 4. J/mol at 2. 5–1. 20 . This makes chitosan water- soluble and a bioadhesive which readily binds to negatively charged surfaces. ![]() Chitosan enhances the transport of polar drugs across epithelial surfaces, and is biocompatible and biodegradable. It is not approved by FDA for drug delivery though. Purified quantities of chitosans are available for biomedical applications. Chitosan and its derivatives, such as trimethylchitosan (where the amino group has been trimethylated), have been used in nonviral gene delivery. Trimethylchitosan, or quaternised chitosan, has been shown to transfect breast cancer cells, with increased degree of trimethylation increasing the cytotoxicity; at approximately 5. Oligomeric derivatives (3–6 k. Da) are relatively nontoxic and have good gene delivery properties. The cellular targets are the plasma membrane and nuclear chromatin. Subsequent changes occur in cell membranes, chromatin, DNA, calcium, MAP Kinase, oxidative burst, reactive oxygen species, callose pathogenesis- related (PR) genes and phytoalexins. It is one of the most abundant biodegradable materials in the world. Degraded molecules of chitin/chitosan exist in soil and water. Chitosan applications for plants and crops are regulated by the EPA, and the USDA National Organic Program regulates its use on organic certified farms and crops. Chitosan active biopesticides represent a new tier of cost- effective biological control of crops for agriculture and horticulture. When used as seed treatment or seed coating on cotton, corn, seed potatoes, soybeans, sugar beets, tomatoes, wheat and many other seeds, it elicits an innate immunity response in developing roots which destroys parasitic cyst nematodes without harming beneficial nematodes and organisms. The US Forest Service has conducted research on chitosan to control pathogens in pine trees. NASA confirmed chitosan elicits the same effect in plants on earth. Chitosan causes the fine sediment particles to bind together, and is subsequently removed with the sediment during sand filtration. It also removes phosphorus, heavy minerals, and oils from the water. Chitosan is an important additive in the filtration process. Sand filtration apparently can remove up to 5. In combination with bentonite, gelatin, silica gel, isinglass, or other fining agents, it is used to clarifywine, mead, and beer. Added late in the brewing process, chitosan improves flocculation, and removes yeast cells, fruit particles, and other detritus that cause hazy wine. Chitosan combined with colloidalsilica is becoming a popular fining agent for white wines, because chitosan does not require acidic tannins (found primarily in red wines) with which to flocculate. These products and uses are approved for European use by the EU and OIV standards. Marine Corps to quickly stop bleeding and to reduce blood loss, and result in 1. Army and are currently used by the UK military. Both the US and UK have already used the bandages on the battlefields of Iraq and Afghanistan. The protonated chitosan is broken down by lysozyme in the body to glucosamine. The chitosan salt may be placed on an absorbable backing. Tephaflex polymer) or natural (e. In addition to salts, hydrogel- based chitosan bandages have been developed to treat burn wounds. Burns are similar to other wounds, but are problematic because they are associated with membrane destabilization, energy depletion, and hypoxia, all of which can cause severe tissue necrosis if not treated properly or quickly enough. Chitosan- gelation bandages using nanofibrin have been shown to be more durable than ointments, while still allowing gas exchange at the cell surface. This positive charge comes from protonation of its free amino groups. ![]() Lack of a positive charge means chitosan is insoluble in neutral and basic environments. However, in acidic environments, protonation of the amino groups leads to an increase in solubility. The implications of this are very important to biomedical applications. This molecule will maintain its structure in a neutral environment, but will solubilize and degrade in an acidic environment. This means chitosan can be used to transport a drug to an acidic environment, where the chitosan packaging will then degrade, releasing the drug to the desired environment. For example, a composite with hydroxyapatite was effective as a temporary post- operation bone filler, which was gradually biodegraded and replaced by native bone tissue. When a scratch damages the chemical structure, the chitosan responds to sunshine by forming chemical chains that bond with other materials in the substance, eventually smoothing the scratch. The process can take less than an hour. A Cochrane meta- analysis. Other higher quality trials indicated no significant effect of chitosan and no clinical justification for advising overweight patients to take chitosan supplements. Food and Drug Administration (FDA) issued warning letters to supplement retailers who made inappropriate claims about the supposed health benefits of using chitosan. The plastic also included grapefruit seed extract, which has antibacterial and antifungal properties, and is an antioxidant, antiseptic and anti- viral. The film blocked the transmission of ultraviolet light — slowing oxidation and photochemical deterioration. The plastic can use raw ingredients that would otherwise be discarded, and biodegrades once discarded. Journal of Agricultural and Food Chemistry. Mediterranean Journal of Chemistry. Retrieved 1. 9 October 2. Patent 4,1. 95,1. Dong Woog Lee; et al. Carbohydrate Polymers. Journal of Controlled Release. PMID 1. 58. 20. 41. Plant Science. PMID 2. Environmental Protection Agency (EPA). February 2. 00. 1. Agro Food Industry Hi- Tech. Monday, December 1. ![]() Rules and Regulation. Archived from the original(PDF) on 1. ![]() December 2. 00. 8. Regulations. gov. December 2. 00. 8. Applications of Chitan and Chitosan. ISBN 9. 78- 1- 5. ![]() Journal of Food, Agriculture & Environment. Archived from the original(PDF) on 5 September 2. C.; Stoner, R. Advances in Plant Ethylene Research. ISBN 9. 78- 1- 4. Molecular Plant- Microbe Interactions. PMID 9. 00. 22. 76. ![]() NPR Morning Edition – KUNC 9. FM Greeley, CO. A.; Fisk, H. Plant Physiology. PMC 1. 05. 44. 05 . PMID 1. 66. 65. 81. Elicitor Response Comparison to Chitin / Chitosan in Mung Bean and Adzuki Bean Germination Experiments. Federal Register Notice of Availability. December 2. 00. 8. US Environmental Protection Agency. US Environmental Protection Agency. Retrieved 1. 0 July 2. Federal Highway Administration. Department of Transportation. Retrieved 1. 0 July 2. International Dairy Journal. J Dairy Sci. 8. 4 (2): 3. PMID 1. 12. 33. 02. Archived from the original on 1. June 2. 00. 6. Retrieved 1. July 2. 00. 6. Minerva Biotecnologica. Wine Maker Magazine. Retrieved 2. 4 May 2. Food Additives & Contaminants: Part A. PMID 2. 25. 45. 59. Guadalupe; Aguilar- Uscanga, Patricia M.; Hayward- Jones, Patricia; Mendoza, Mario; Ram. Journal of Industrial Microbiology and Biotechnology. PMID 1. 47. 47. 93. Int J Clin Exp Med. PMC 4. 35. 84. 24 . PMID 2. 57. 84. 96. Comprehensive biomaterials. Amsterdam: Elsevier. ISBN 9. 78. 00. 80. The Journal of Emergency Medicine. PMID 1. 80. 24. 06. The Journal of Trauma: Injury, Infection, and Critical Care. PMID 1. 25. 44. 91. Symposium on Combat Casualty Care in Ground Based Tactical Situations: Trauma Technology and Emergency Medical Procedures, St. Petersburg Beach, US. Retrieved 5 June 2. Chemistry. org. American Chemical Society. Archived from the original on 2. November 2. 00. 5. Retrieved 1. 0 July 2. Royal Society of Chemistry. RSC Adv.,2. 01. 4,4,6. Retrieved 1. 9 October 2. Regulatory Toxicology and Pharmacology. PMID 1. 97. 88. 90. Royal Society of Chemistry. RSC Adv.,2. 01. 4,4,6. Retrieved 1. 9 October 2. Neurosciences (Riyadh). PMID 2. 38. 87. 22. Journal of Controlled Release. PMID 1. 54. 91. 80. Journal of Biological Physics and Chemistry. Retrieved 2. 4 May 2. A.; Wuitschik, G; Rogers- Evans, M; M. Angewandte Chemie International Edition. PMID 2. 10. 31. 37. PMID 1. 92. 86. 55. New Scientist- Tech. Retrieved 2. 4 May 2. Macromolecular Materials and Engineering. Journal of Biomedical Materials Research. PMID 1. 45. 66. 80.
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