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Kitin

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A kitin molekulaszerkezete: az ismetl?d? N -acetilglukozamin alegysegek beta-1,4 kotessel hosszu lancokat alkotnak

A kitin ( C 8 H 13 O 5 N ) n egy hosszu polimer lancmolekula, melyet N -acetilglukozamin molekulak alkotnak es a termeszetben sok helyen el?fordul. A poliszacharidok koze tartozik. Nevet a gorog khiton (χιτ?ν = ruha, takaro) szobol kapta. [1]

A gombak sejtfalanak f? komponense, valamint az izeltlabuak ( rakok , rovarok ) kuls? vazanak alkotoja is. A rakok es a rovarok pancelanyagaban talalhato kitin konnyen elkulonithet?, mert a kitin kemiailag nagyon ellenallo. Vizben, hig savakban es lugokban oldhatatlan. Csak tomeny savval valo melegites hatasara hidrolizal. Hidrolizisekor el?szor N -acetil- d -glukozamin , majd d - glukoz es ecetsav kepz?dik. Szerkezete a cellulozeval analog, az N -acetil- d -glukozamin egysegek kozott β (1→4) kotesek talalhatok.

A kitint szamos orvosi es ipari teruleten felhasznaljak.

A kitin mint nyersanyag [ szerkesztes ]

Mig Japanban evi 300 tonna kitinb?l keszitenek tolt?anyagot az ivovizet tisztito berendezesek celjara, a vilag tobbi orszagaban kitinb?l alig keszul valami. Igaz, a kitin csak nagy energiaforditassal dolgozhato fel, megis sok szakember szerint az igy kapott anyagok a termelesi koltsegeiknel joval dragabban ertekesithet?k.

Az orvostudomany szerint a kitin vegyileg modositott formajaval, kitozannal egesi sebek kezelhet?k. Tobb kiserlet tanusaga szerint nagy felulet? egesi sebeket eredmenyesen gyogyithatunk kitozan-acetat-filmmel. A vizben oldodo film atereszti az oxigent , s felszivja a sebfolyadekot. Majd a filmet a seb lizozim nev? enzimje lassankent lebontja. Mas kiserletek azt mutattak, hogy a kitozan gatolja a bakteriumok szaporodasat es a b?rgombak fejl?deset. S talan keszithetnek bel?le veralvasztot is.

Botanikusok szerint a kitozant novenyved? szerkent szinten alkalmazhatnak, leven, hogy a haszonnovenyeket megovja a gombafert?zesekt?l. Noha ennek meg nem ismerik a pontos mechanizmusat, azt maris megallapitottak, hogy vele a borsonovenyek megvedhet?k a gombafert?zesekt?l. Annak a lencsenek es azoknak a buzafajtaknak , amelyeknek a magjait kitozannal kezeltek, 10?30 szazalekkal lesz tobb a termeshozamuk.

Japan kutatok azt allapitottak meg, hogy a talajba kevert kitozannal javithato a mez?gazdasagilag hasznositott homoktalajok vizhaztartasa. A kitozan es szarmazekai, noha nincs bennuk feherje , a takarmanyhoz is adagolhatok. Azok a csibek es borjak , amelyeknek a takarmanyaba egy keves kitozant kevertek, konnyen lebontjak a tejcukrot . Ez modot ad arra, hogy ezeket az allatokat a sajtkeszit? uzemekben keletkez? tejsavoval etessek.

Jegyzetek [ szerkesztes ]

  1. ↑ Fulop Jozsef: Rovid kemiai ertelmez? es etimologiai szotar. Celldomolk: Pauz?Westermann Konyvkiado Kft. 1998. 79. o. ISBN 963 8334 96 7  

Forrasok [ szerkesztes ]

  • Elet es Tudomany: A kitin mint nyersanyag (Frankfurter Allgemeine Zeitung)
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