• Journal of Biomedical Engineering Research
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• v.16 no.3
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• pp.257-264
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• 1995

The $\beta$-chitin derivatives were synthesized by reacting $\beta$-chitin with chloropropane, propyleneoxide and chloropropane diol to form propyl chitin (PPC), hydroxypropyl chitin (HPC) and dihydroxypropyl chitin (DHPC), respectively. Cast films from $\beta$-chitin and $\beta$-chitin derivatives solutions degraded by Iyrozyme in pseudo-extrra cellular fluid (PECF) solutions, at pH1.2, pH6.7 and pH8.2. Chitin derivatives rapidly degraded compared with virgin $\beta$-chitin within the first week. DHPC showed the best biodegradation among these derivatives.

• Food Science and Industry
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• v.53 no.1
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• pp.33-42
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• 2020

In accordance with the recent trend of environmentally friendly agricultural policy, product registration of agricultural chitosan among the organic materials has been displayed in various forms such as soil improving agent, crop growth, and pest control. Chitin production industry is expected to bring competitiveness by producing low-quality and low-cost chitin for agriculture, rather than high-quality and high-cost for food, medical products. Since there are various soil microorganisms that can decompose chitin and chitosan in farm soil where crops are produced, it can be applied usefully to agricultural sites suitably for crop growth and pest control using chitin and chitosan as substrates. The purpose of this study is to compare and analyze the registration status of organic materials companies using chitin and chitosan raw materials in the organic materials information system of the NAQS, and to provide an opportunity to further expand the agricultural use of domestic chitin and chitosan.

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.1
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• pp.105-113
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• 1995

Procedures for isolatin of chitin have been developed from crab(Chionoecetes opilio) shell waste with 26. 65% chitin on a dry basis. Optimal conditions for demineralization of crab shell were 1N HCl at ambient temperature for 30min with a solids to solbent ratio of 1 : 15(w/v). Optimal deproteinization involved treatment with 5% NaOH at $65^{\circ}C$ for 1 hr with a solids to solvent ratio of 1 : 15(w/v). Effective decoloration was achieved by bleaching with 0.32% sodium hypochlorite solution for 3min with a solids to solvent ratio of 1 : 10(w/v). Particular attentin was given to characterization of the physicochemical properties of the crab chitin. Chitins, from four different mesh sizes of crab shell, did not show significant differences in nitrogen and ash compositions. Bleaching decreased the viscosity of chitin but did not affect its solubility.

• Journal of Life Science
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• v.3 no.2
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• pp.91-114
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• 1993

키틴은 N-아세틸-D-글루코사민 잔기가 다수 beta-(1, 4) 결합하고 있는 다당류이고, 그 탈아세틸화물을 키토산이라 한다. 키토산도 D-글루코사민의 beta-(1, 4) 중합체이지만 보통 약간의 아세틸기를 가지고 있는 것을 키토산이라 부르고 있다. 현재로는 제조 키틴의 대부분이 키토산으로 변환되어 응집제로서 폐수처리에 이용되고 있고, 기타 많은 용도가 개발되어 있지만 아직 연구단계에 있다. 따라서 키틴이나 키토산 분자의 잠재적 기능을 개발하여 인간생활에 유효하게 이용하도록 한다는 것은 폐기물 처리나 미이용 지원의 개발이라는 측면에서 볼 때 중요한 문제라고 볼 수 있다. 따라서 본고에서는 키틴의 생물계에서의 분포, 입체배좌, 제조법, 물성 및 기능성 그리고 그 용도에 대해 간추렸다.

• Bulletin of Food Technology
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• v.12 no.3
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• pp.8-13
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• 1999

키틴/키토산은 지질흡수의 억제, 혈중 콜레스테롤의 저하, 항고혈압활성, 면역활성, 항종양/항암활성 등 다양한 생체기능성을 나타내어 건강지향적인 기능성 식품으로서의 이용가치가 매우 큰것으로 평가되고 있다. 키토산은 성인남자의 혈중 콜레스테롤을 감소시키고 HDL cholesterol은 증가시켜 동맥경화지수를 낮추며 비만환자에게 투여시 체중, 중성지질, LDL cholesterol을 유의하게 낮춤으로서 고지혈증과 비만증의 개선에 유용한 것으로 평가된다. 키토산은 또한 성인의 고염식에 의한 혈압상승을 억제하며 3량체 내외의 키틴/키토산 올리고당은 혈압상승의 중요인자인 angiotensin converting enzyme과 직접 반응하여 활성을 현저히 저하시키고 SHR에서의 혈압을 유의하게 억제하는 특성을 보여 고혈압의 억제 및 치료에도 응용가치가 클 것으로 생각된다. 키틴/키토산 및 그 올리고당은 sarcoma 180, Meth-A solid tumor의 성장을 저해하고 L1210와 같은 negative charge를 갖는 malignant cell을 흡착시키는 등 항종양/항암활성을 보이는데 이는 tumoricidal immunocite의 활성화에 의한 것으로 추정되고 있다. 키틴/키토산의 생체활성은 분자크기, 탈아세틸화도, 유도체의 종류 및 적용방법 등에 따라 차이를 보이기 때문에 키틴/키토산을 기능성 식품으로서 폭넓게 이용하게 위해서는 용도에 맞는 적절한 규격 설정이 요구되고 있다.

• Applied Chemistry for Engineering
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• v.3 no.3
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• pp.516-521
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• 1992

Hydroxypropyl chitin (HPCH) was prepared by reacting chitin with propylene oxide. HPCH showed the improved solubility in several organic solvents compared with chitin. It showed the remarkable solubility in formic acid. Form the results of polarized microscopic observatoin of HPCH solution in formic acid, finger-print pattern was observed in concentrations over 30 wt% solution. Since no typical thermogram was observed in DSC scan, the HPCH showed a lyotropic cholestric liquid crystallinity.

• Applied Chemistry for Engineering
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• v.4 no.4
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• pp.785-790
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• 1993

Three ester-type chitin derivatives were synthesized by reacting chitin with acetic anhydride, propionic anhydride and n-butyric anhydride to form acetyl chitin(AC), propionyl chitin(PC) and n-butyryl chitin(BC). Methanesulfonic acid was used as a catalyst. FT-IR spectra and solid state CP/MAS $^{13}C-NMR$ spectra of three chitin derivatives showed that the substituents were mainly incorporated in the $C_6$ position of chitin. The ester-type chititn derivatives were dissolved well in formic acid and swollen in aqueous acidic solution.

• Journal of Biomedical Engineering Research
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• v.15 no.1
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• pp.89-96
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• 1994

The ether-type chitin derivatives were synthesized by reacting chitin with chloropropane, propylene oxide and chloropropane diol to form propyl chitin(PPC), hydroxypropyl chitin(HPC) and dihydroxypropyl chitin(DHPC). These derivatives formed a lyotropic cholesteric liquid crystallinity in concentrations over 30 wt% solution in formic acid (99%). Cast films from liquid crystalline solutions were degraded by lysozyme in pseudo-extra cellular tluid(PECF)solutions, at pH 1.2, pH 6.7 and pH 8.2. Three ether-type chitin derivatives rapidly degraded within the first week, and showed a decreased mechanical strength in neutral pH range. Dihydroxypropyl chitin showed the best biodegradation among these derivatives.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.25 no.1
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• pp.45-50
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• 1992

To utilize shellfish by-products effectively, chitin, chitosan, and microcrystalline chitin were prepared from 6 kinds of crustacean shells(Antarctic krill, Euphausia superba; Red snow crab, Chinonecetes japonicus: Daelongsuyum shrimp, Solenocera prominentis: Lobster, Linuparus trigonus: Gasibal shrimp, Nephrops thomsoni: Blue crab, Portunus trituberculatus) and their functional properties were studied. Apparent volume(AV), settling volume(SV), water binding capacity(WBC), and fat binding capacity(FBC) of various chitins, chitosans, and microcrystalline chitins ranged from $3.1\pm0.1ml/g\;to\;27.0\pm0.2ml/g$ from $5.1\pm0.1ml/g\;to\;45.0\pm0.2ml/g,\;from\;318\pm40g/100g\;to\;2,382\pm12g/100g,\;and\;from\;235\pm20g/100g\;to\;2,169\pm20g/100g$, respectively, and the krill chitin and chitosan had the highest AV, SV, WBC, and FBC of them. Chitins and chitosans did not produce emulsion but microcrystalline chitins showed emulsifying properties. Emulsifying capacity and stability of various microcrystalline chitins ranged from $18.2\pm4.0\%\;to\;50.1\pm2.5\%\;and\;from\;15.2\pm3.5\%\;to\;31.1\pm1.0\%$, respectively. Dye binding capacity of microcrystalline chitins was higher than that of chitins or chitosans.

• Applied Biological Chemistry
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• v.40 no.2
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• pp.95-100
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• 1997

This study was aimed to survey inexpensive and reliable sources of chitinase from the animal origin. The stomach and its content of the broiler, the cod, the yellowtail and ${\beta}-glucuronidase$ from snail gut showed a considerable chitinolytic activity, while those of the bas didn't have any detectable activity. These crude enzymes was found to have both endo- and exochitinase activity. The effects of pH and temperature on the enzyme activity were variable. The hydrolytic products of colloidal chitin by the enzyme preparation from the broiler and the cod were chitooligomers having the degree of polymerization between 3 and 5. Furthermore we observed the chitosanolytic activity from these enzymes. In the degradation of chitosan the chyme of the broiler had the highest activity and ${\beta}-glucuronidase$ from snail gut followed. On the basis of the fact that the by-product of the broiler was not only commercially available but also the most potent in the endochitinase activity and the lowest in the exochitinase activity, we conclude that the gizzard and its chyme are considered as the most suitable source of the industrial chitinase among animals studied in this paper.