Chitin%20is%20a%20polysaccharide;%20it%20is%20synthesized%20from%20units%20of%20N-acetylglucosamine%20(more%20completely,%20N-acetyl-D-glucos-2-amine).%20These%20units%20form%20covalent%20

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• Chitin is a polysaccharide it is synthesized
  from units of N-acetylglucosamine (more
  completely, N-acetyl-D-glucos-2-amine). These
  units form covalent ß-1,4 linkages (similar to
  the linkages between glucose units forming
  cellulose).
• ??????????(???chitin ?natural chitosan and
  modified chitosan?glucosamine?N-acetyl
  glucosamine)????????????????????????????
• A type of polysaccharide (sugar molecule) that is
  made by some plants and animals. The hard outer
  shell of shrimp, lobsters, and many insects is
  made of chitin.

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• ???(C8H13O5)n ,?????????,????,???8000?ß??????????,
  ?????????????????
• ???????????????????????????????????????????????

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(No Transcript)
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???(chitin)

• ???(chitin)?????????,?N-??????(N-acetyl
  glucosamine)?????, ??ß1-4??????????,??????????????
  ?????????
• ???????????,??????????????????????????????????,???
  ?(?????,????,chitosan),????(polymers)???(oligomers
  )???(monomers),?????????????????????,?????????????
  ??????40??,??????40???????????

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?????????

• ????????????????,?????????????
• N-??-D-????????,???ß-1,4??(?????????????????),????
  ??????????????????????????????
• ?????????????????,??????????

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?????????

• ????????,???????,??????,???????
• ??????????????,?????????????,?????????????????????
  ?,???????????,???????????????

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?????????

• ?????????????????????????????????????
• ???????????????????
• ????????,??????????????????????

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????--??

• ???????(?????????????????,?????)?????
• ?????????????????????????????????
• ???????????????Chitin????????chitine?
• ?????1836?????????chiton?,??????,???????khiton,???
  ??????????

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???????

• ??????????
• ????????????
• ???????????????
• ????????????
• ??????????????????
• ????????????????

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??????

• ??????????????????????
• ?????????,???????????,??????????????????

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?????????

• ????????????????(exoskeloton),???,?????????????,??
  ????????Chitin?????Chiosan?
• ????????????,??????????????????????,????????????
• ?????????????????????micelle(??? )
• ???????????????,???????????????????

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???????

• ??????????????4751,?????????3241???
• ?????????,???1g?????????12g??????
• ????????????,?????????,????????????????

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Chitin was first investigated in 1811

• Chitin was first investigated in 1811 by
  Professor Henri Braconnott, who discovered it in
  the cell walls of mushrooms.
• In the 1830s, it was isolated in insects and
  named chitin. Chitosan, a derivative of chitin,
  was produced in 1859, and since then, research
  has been conducted to learn about the properties
  of chitin and chitosan and develop commercial
  applications for their use.

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arthropods

• Like all arthropods (the large group which
  includes insects, scorpions, shrimp, and
  lobsters), horseshoe crabs have a hard outer
  shell, or exoskeleton, that provides protection
  from predators.
• Millions of tightly interwoven strands of a
  cellulose-like material called chitin serve as a
  tough and flexible glue that holds together the
  shell.
• The chitin in horseshoe crabs is favored for
  research over that found in other arthropods
  because it is very pure.

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Chitin is natural, non-toxic

• The combination of chitin's remarkable properties
  makes it extremely versatile.
• Chitin is natural, non-toxic, non-allergenic,
  anti-microbial, and biodegradable.
• It has a strong positive charge, which allows it
  to bind with negatively charged surfaces or
  materials, including metals, skin, and
  macromolecules such as proteins.

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Cellulose, chitin, and starch

• Cellulose, chitin, and starch are the three most
  abundant organic compounds in nature. Cellulose
  and starch are key carbohydrates that plants use
  as a food source and to build cell walls.
• Chemically, chitin is a polysaccharide. A
  polysaccharide is a polymer a large molecule
  consisting of smaller (and in this case, sugar)
  molecules strung together.

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chitosan

• Chitin can be processed into many derivatives,
  the most readily available being chitosan, which
  is formed when chitin is heated with a chemical
  solution.
• Chitosan has some advantages over chitin because
  it is more water-soluble.

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chitin-related products

• By the 1940s, almost 50 patents had been filed
  for chitin-related products.
• But commercial development of chitin proceeded
  slowly, partly because synthetic products were
  already in use in some applications, and there
  was a lack of strong federal support for chitin
  research and the development of chitin products.

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the thousands of tons of shellfish waste produced
annually

• In the mid-1970s, however, environmental
  regulations were passed to limit the dumping of
  untreated shellfish wastes in coastal waters,
  thus making the processing of chitin from
  shellfish waste an economical way to comply with
  the regulations and dispose of the thousands of
  tons of shellfish waste produced annually.

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15 major processors

• Today, nearly 200 patents have been issued in the
  United States, in addition to those issued in
  several other countries worldwide, and there are
  nearly 15 major processors of chitin and chitosan
  around the world.

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wound-healing properties

• Early on it was found that chitin had
  wound-healing properties.
• By the mid-1950s, chitin-coated sutures were
  being used, which enhanced healing time by 35 to
  50.
• In the 1970s, researchers with the University of
  Delaware Sea Grant College Program developed a
  method to spin pure chitin filaments.

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new chitin sutures

• These new chitin sutures could be absorbed by the
  body, eliminating the need for surgical removal.
• A Japanese firm bought the patent rights, and
  suture materials are now manufactured in Japan.

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accelerate healing and reduce pain

• In addition, this firm uses chitin to make
  dressings for burns, surface wounds, and
  skin-graft donor sites, which dramatically
  accelerate healing and reduce pain compared to
  standard treatments where the dressings must be
  removed.

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artificial blood vessels

• Other medical uses for chitin include
  anti-bacterial sponges and hospital dressings,
  artificial blood vessels, contact lenses, tumor
  inhibition, dental plaque inhibition, and blood
  cholesterol control.
• Household products include sponges, diapers,
  feminine napkins, and tampons.

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Water Treatment

• Water Purification As a polymer, chitosan's
  natural tendency is to form long chains of
  molecules with positive charges, which act like
  hooks.
• These natural hooks catch organic materials, such
  as oils, detergents, and other contaminants
  suspended in water.
• The material then coagulates to form flakes that
  are easily filtered out. Filtration companies are
  using chitin in clarifiers to help filter
  particulates and chemicals from water.

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Wastewater Treatment In Japan

• chitosan was first used for wastewater treatment
  because of its metal-binding properties.
• It is also good for cleaning up toxic organic
  compounds, such as PCBs.

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Dietary Supplements

• Chitosan has properties similar to plant fiber
  and can significantly bind fat, acting like a
  sponge in the digestive tract.
• It is not digestible itself and the bound fat
  leaves via the body without ever entering the
  bloodstream.

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Cosmetics

• Make-up powder nail polish moisturizers face,
  hand, and body creams and toothpaste are just a
  few consumer products that might contain chitin.

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Agriculture

• Seeds treated with chitosan are larger and
  stronger and more resistant to fungal diseases.
• Treating seeds with chitin can increase crop
  yields by up to 50.

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feed mixtures

• Chitin is added to commercial feed mixtures
  containing whey, a by-product of the cheese
  industry.
• Many animals find it hard to digest the
  high-lactose whey.
• But chitin supports the growth of beneficial
  microorganisms in the animals' digestive tract
  these bacteria produce enzymes that help the
  animals digest whey.

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• ??????????????,?????(????????????)???????????,????
  ???????????????,
• ???????????????????????????,??????????????????????
  ??????????
• ????????????????????????????????????????????????,?
  ??????????

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???????????

• ????
• Mitchell ??1959????????(chitin)????(chitosan)??
  ?????Fusarium spp., ?Allan ?Hadwiger
  ??????????????????????????????????????????????????
  S. aureus? Bacillus cereus? Escherichia
  coli?Vibro cholerae?Listeria monoctogenes ? ?

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???????

• ?????????????????????(-NH3)????????????????????
• ????????????,????????,?????????????????

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???????

• ??????????????????????pH????????,???,????????????
  ???????,????????????????,??????????????????????

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???????

• ??????????????????????????????
• ????????????????????????,????????????????????
• ???????????????????,??80?60?????????Pseudomonas
  fluorescens ? Shigella sonnei ????,
  80???????????????????60 ???????????

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?????

• Kender ?Hadwiger ??????????????????????(degree
  of polymerization DP)????6???????????????????????
  ??
• ????(M.W. 685kDa, DDA 89 ))??????????????????????
  ??,???????????,???????????10 kDa????????
• ?????????????????????????????????????????????

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?????????

• ???????????,?????????????????????????????????,????
  ???????????????,??????????????????

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?????

• ??????????????????,?????????,???????????
• ??????????,?????????????????????????????,Kanauchi?
  ????? ?????????????????????(micelle),????????????
  ????,?pH????????????????(gel)??,????????????,????(
  gel)?????????????????????
• ???????C???,?????????????,??????,???????

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???????

• ???????????????,??????????(??),
  ??????????C?????????????
• ??????????????????????,??????????????????,?????,??
  ??????????

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???.??????

• ?????????????,?????????????,??300 kDa? 20 kDa? 8
  kDa?600 Da???????????????????8 kDa??????????????,6
  00 Da?????
• ???20 kDa ??????????????Ikeda???2-50
  kDa??????????????????,??????????2 kDa????????
• ????8 kDa??????????????220 kDa???
• ?Lehoux ? Grondin ????????750 kDa?????????????????
  ?????,????2000 kDa??????

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???????????

• ????????,????????????????????????????????????????
  ????,??????T?????????????
• ?Mori????????????????????????????-8
  (Interleukin-8),???N-????????????????
• ????N-?????????????????????(NO)????????????
• ?????????????T????????????????

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?????

• ???????????????????,?????????????????,????????????
  ?????????????????????????
• ???????????????,??????????????,???????????????,??c
  hitinase ?pisatin? phytoalexin polyphenolic,ß-gluc
  anase ???????????????

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?????????

• Ghaouth??? ???????????????????chitinase?
  chitosanase ?ß-1,3 glucanase ????,????Pythiun
  aphanidermatum ??????????
• ???????????pisatin ?????Fusarium solani ??
• ?????????phytoalexin?????????????????,?phytoalexin
  ??????????????????????????????,
• ???????????????????????????????
• ???????????????????????????????????????

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????

• ????????????????????
• ???????? ?????(Colloid titration)??????(Direct
  titration)???????(UV spectrophoto- metric
  method)??
• ?????????????????????????(infrared
  spectroscopy)????????(NMR spectroscopy)????????(HP
  LC) ??

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???????????

• ???????????????????????????????????????,??E.coli
  ???????
• 2???,????E.coli??????(??????????0.002
  ),?????30???????,???NB????37???24??,???????????

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????58.4 kDa??????

• ??????? E. coli ????????????,??????????????????58.
  4 kDa?????????????????
• ???????????S. aureus ??????????????

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????

• ?0.05g (150-400 mesh) ??????????2.5ml 0.1N
  HC???????20g??,?????????pH2
• ???????37??????2??,???16 ml 10mM PBS ????
• ??pH?7.00.2,??????37 oC????30??
• ?2500rpm??30???, ????????oil/gel(oilchitosan)/wa
  ter??,?????????????
• ?? Binding Index oil bound (g) / chitosan (g)
  oil bound????(20g)-????????????

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?????????

• ??????,?????????,??????????????????,??????????????
  ????????????????

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2????????

• ???????2??????????????????????????,?????20???????
  ???,????????(Fusarium oxysporum)????????????
• ???????????????????????
• ????????????????????????(?????????)
  ???????????????????200?????????1800???????????????

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???????????

• ??????????????????????
• ????????????????????,??????????,??????????????????
  ???????????????,?????????????

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• ?????????????????????????????????????????????,????
  ??????????????????,???????????????????
• ???????????????????????????????????????????????
• ?????????????????????????????????????????????????
  ???????,?????????