• 한국염색가공학회지
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• 제11권2호
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• pp.55-63
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• 1999

The purpose of this study was to investigate the purification of chitin and chitosan for textile finishing agent from crab shell. Weight loss rate(removing Ca and protein), degree of deacetylation, solubility and MIC(Minimum growth inhibitory concentration) value of chitosan and molecular weight of the treated crab shell were measured. The results of this study were as follows : 1) Weight loss rate(removing Ca) of crab shell treated with HCI increased with the concentration of HCI and treatment time, but it became constant over 60 min. of treatment time. 2) Weight loss rate(removing protein) of crab shell treated with NaOH(0.5N∼2N) increased with the concentration of NaOH and treatment temperature and time, but it became constant above loot of temperature and over 200 min. of treatment time. 3) Degree of deacetylation of chitin treated with NaOH increased with the concentration of NaOH(40∼60％), but molecular weight decreased and thus MIC value increased. 4) Concentration of acetic acid should be above 0.3％ to dissolve chitosan easily. Solubility for chitosan was the highest with formic acid, and the next was acetic acid, hydrochloric acid, lactic acid and sulfuric acid in order.

• 복식문화학회:학술대회논문집
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• 복식문화학회 2003년도 International Exhibition and Workshop
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• pp.24-25
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• 2003

Water-soluble chitosan and water-insoluble chitosan with molecular weight of 2,000,000, 500,000, 80,000, and 40,000 and more than 90% degree of deacetylation were controlled to evaluate the antibacterial activity of chitosan against a pathogenic bacteria, methicillin resistant Staphylococcus aureus(MRSA), which is being issued in the world. The Shake Flask Method and Modified Shake Flask Method were used to find out the antibacterial activities of 5types of chitosan/acetic acid solution, and the other antibacterial activities test with the cotton filter treated with chitosan /acetic acid solution. Those test methods showed the great differences ,but the results of the antibacterial activites showed the same difference.

• 한국식품과학회지
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• 제27권3호
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• pp.420-427
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• 1995

저분자 chitosan이 김치의 보존성에 미치는 영향을 조사하기 위해 분자량이 다른 4종류의 저분자 chitosan을 양념을 첨가하지 않은 배추김치의 모델 시스템(소금 농도 2%)에 0.5%씩 첨가하고 $20^{\circ}C$에서 발효시키면서 김치의 특성 변화를 살펴보았다. 동일 발효기간내에서 대조군이 chitosan 첨가군들에 비해 pH는 낮고 총산함량은 높았으며 환원당 함량은 발효 6일까지 대조군이 chitosan 첨가군들에 비해 더 낮은 경향이었다. 유기산 중 malic acid 함량은 발효 4일까지 대조군이 chitosan 첨가군들에 비해 낮은 경향을 보였으며, succinic acid 함량은 발효 2일째에 그리고 lactic acid와 acetic acid 함량은 발효 4일째에 대조군이 chitosan 첨가군들에 비해 높은 경향을 나타냈을 뿐 나머지 발효기간에서는 큰 차이를 보이지 않았다. 또한 propionic acid 함량은 발효 6일 이후에 미량으로 나타났으며, 대조군이 chitosan 첨가군들에 비해 높은 경향을 보여주었다. 총균수, Leuconostoc속 미생물 수, Lactobacillus plantarum의 수는 전 발효기간 동안 대조군이 chitosan 첨가군들에 비해 더 많았으며 특히 chitosan 첨가군들은 대조군과 비교했을때 Leuconostoc속 미생물보다 산패균인 Lactobacillus plantarum의 생육을 훨씬 크게 억제시켰다. Leuconostoc속 미생물 수에 있어서 분자량이 적은 chitosan 첨가군들이 분자량이 큰 chitosan 첨가군들에 비해 적은 경향이었으며 Lactobacillus plantarum의 수는 chitosan 첨가군들간에 큰 차이를 보이지 않았다. 관능검사로 조사한 신맛과 군덕내는 대조군이 chitosan 첨가군들에 비해 강했으며, 경도는 큰 차이를 보이지 않았으나 대조군이 더 약하게 평가되었다. 또한 이취는 전 실험군에서 모두 약하게 평가되어 이취는 chitosan에 의해 큰 영향을 받지 않는 것으로 나타났다.

• Journal of Biosystems Engineering
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• 제31권4호
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• pp.363-368
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• 2006

The effects of germinating types and treatments of acetic acid, water-soluble and water-insoluble chitosan on the germination ratio and sprout length of brown rice were investigated in this study. The treatment of 0.001% acetic acid improved the germination ratio and sprout growth of brown rice in the germinating types of a air-exposure method after water-soaking (Type II) and a repetitive method of water-soaking & air-exposure (Type III), not water-soaking method (Type I). The treatment of water-soluble chitosan with higher concentration caused higher germination ratio and faster sprout growth. The treatment of water-insoluble chitosan repressed the germination and the sprout growth of brown rice. The germination ratios of brown rice germinated by the Type III were higher than those by Type I and Type II for all the treatments of acetic acid and water-soluble & water-insoluble chitosan as more than 97% germination ratio. Also, the Type III method accelerated the sprout growth of brown rice compared with Type I and Type II.

• 대한가정학회지
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• 제42권3호
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• pp.145-158
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• 2004

Experimental conditions for evaluating chitosan antibacterial activities were established. The chitosan antibacterial activities were measured against the Staphylococcus aureus and evaluated for their application to antibacterial textile finishing. The strain of Staphylococcus aureus used in this experiments was KCTC 1916. The chitosan antibacterial activities were estimated from the bacterial densities or ％reduction of bacteria in chitosan solutions and bacterial culture mixtures after incubation under specific conditions. Six parameters as follows were evaluated to optimize the experimental conditions for measuring antibacterial activities. The different combinations of mixtures according to the different ratios of chitosan solutions to the bacterial cultures showed different antibacterial activities. However, the chitosan antibacterial activities could be evaluated by comparing the data obtained from the same combinations of mixtures. The solvent influence on the chitosan solution antibacterial activities could be eliminated using control solution containing the same concentration of acetic acid. The initial pH of the chitosan -bacterial mixtures also affected the chitosan antibacterial activity; at a higher pH, higher activity in terms of ％reduction of bacteria was observed. In case of the bacterial solution without either the acetic acid or chitosan, the initial pH of the solution did not significantly affect bacterial growth. The ％ reduction of bacteria increased when contact times of bacteria with chitosan in the chitosan -bacterial mixture were expended upto 24 hours. However, the chitosan antibacterial activities could be successfully evaluated at contact time 0 where the chitosan-bacterial mixture was plated immediately after mixing and incubated to measure the bacterial number to 24 hours. Evaluating ％reduction of bacteria in the test mixtures after incubation were not changed when the inoculated bacterial concentrations were 2.3${\times}$10$\^$0/ml to 2.3${\times}$10$\^$6/ml. The optimal range of incubation time of the petri-Dish after plating the chitosan-bacterial mixture was 24 to 72 hours depending on the antibacterial activities of the test solutions.

• 복식문화연구
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• 제5권3호
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• pp.151-158
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• 1997

This study was to find out the differences of the characteristics on chitosan from source, the crab and the shrimp. Chitosan was depolymerized in NaBO₃·4H₂O under various reaction time and temperature. 4 Chosen chitosan dissolved in acetic acid and treated to cotton fabrics. The cotton fabrics treated with chitosan showed an exellent antibacterial activity irrespective of the viscosity. Stiffness of the treated cotton fabrics increased 3∼8 times than untreated cotton fabric, it gives harshness to treated cotton fabrics, it gives harshness to treated cotton fabrics like linen. Air permeability of the treated cotton fabrics increased. Stiffness and air permeability are respective to viscosity of the chitosan.

• 한국식품영양과학회지
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• 제27권4호
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• pp.648-652
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• 1998

Astringency in persimmons was removed by immersing in 0.5% acetic acid or various concentrations(0.1%, 0.5%, and 1.0%) of chitosan solutions for 4 days at 18$^{\circ}C$. During 5-days immersion, soluble tannin contents in persimmons decreased more rapidly while pH, 。Brix, and hardness decreased more slowly with increasing chitosan concentration. No noticeable color changes and decay were observed during this period. Sensory analyses 4 days after immersion indicated that persimmons immersed in 1.0% chitosan solution showed the best results for firmness and overall acceptability.

• 한국포장학회지
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• 제5권1호
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• pp.47-55
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• 1999

탄수화물에서 유래되는 chitin은 cellulose와 유사한 $poly-{\beta}(1,4)-N-acetyl-D-glucosamine$의 섬유상의 중합체로서 물과 유기용매 녹지 않으나 acetyl amino group 을 탈아세틸화 시키면 키토 산으로 되어 묽은 산 용액에 용해되어 점성이 있는 용액이 되므로 화학, 의학 및 식품 산업분야 등에 다양한 용도로 이용되고 있다. 본 실험에서는 게 가공 폐기물로부터 부가가치가 높은 chitin 및 키토산 을 제조하였으며 침지조건을 달리하여 제조한 키토산의 특성을 조사하였다. 원료인 게껍질의 일반 성분은 수분 8.24%, 지방 3.65%, 단백질 28.73%, 회분 35.5%, chitin 23.55%로 나타났다. chitin의 제조는 5% HCl과 5% NaOH를 침지 온도와 시간을 달리하여 탈회분, 탈단백질하여 제조하였다. 탈회분은 온도에 따라 큰 변화는 없었으며, $30^{\circ}C$에서 30분 반응하였을 때 회분함량이 3.22%, 60분 후 1,07%로 감소했다. $50^{\circ}C$ 및 $70^{\circ}C$에서는 30분 처리하였을 때 1.46%, 1.19%를 나타낸 후 시간이 증가하여도 감소량이 뚜렸하지 않았다. 탈단백질은 위와 동일한 조건으로 침지하였으며 시간이 경과함에 따라 감소하였고 $70^{\circ}C$에서 90분 반응하였을 때 chitin의 질소 함량 6.92%에 근접하였다. 키토선 제조는 chitin을 50% Noah에 침지 시간을 달리하여 탈아세틸화하였다. 탈아세틸화도는 2시간 침지 후 82.84%를 나타내었으며 시간이 경과할수록 증가하였다. 한편 침지 후 여액의 NaOH를 다시 사용하였을 때 키토산의 점도 및 분자량은 시간의 경과에 따라 감소하였다. 즉 점도는 2시간 경과함에 따라 95 cps, 4시간 70 cps, 6시간 65cps, 8시간 60cps로 감소하였으며, 분자량은 110,286, 99,000, 96,666, 94,300으로 감소하였다. 횟수에 따른 점도 및 분자량은 시간의 경과에 따라 증가하였다. 반복 사용된 반응용액에서 제조된 키토산은 기계적인 물성변화는 거의 없었고, 각 solvent에서 반응시간 경과에 따라 약간 증가함이 있었고 acetic acid에 용해하여 제조한 chitosan film의 TS가 lactic acid chitosan film보다 우수함을 알 수 있었다. 수증기투과도의 경우 lactic acid에 용해하여 제조한 chitosan film이 acetic acid에 용해하여 제조한 chitosan film보다 큰 수증기 투과도를 보였다.

• 공업화학
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• 제4권2호
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• pp.324-334
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• 1993

천연고분자인 chitin은 인체에 무해무독하며 생분해성이 있는 것으로 알려져 있다. 이 chitin을 탈아세틸화시켜 얻은 chitosan에 propionyl group을 도입하여 porous bead의 형태로 제조하고 이들의 흡수성수지로서의 가능성을 검토하였다. 실험에 사용된 propionyl chitosan porous bead의 합성은 chitosan을 acetic acid 수용액에 녹인 후 emulsion을 이용한 방법으로 아실화 반응을 일으켜 제조하였으며, crosslinked propionyl chitosan porous bead는 ethyleneglycol diglycidyl ether로 부분가교시킨 chitosan을 사용하여 상기와 같은 방법으로 제조하였다. 이때 propionic anhydride의 몰수와 반응시간 그리고 반응온도를 변화시킨 결과, propionyl chitosan의 합성조건은 propionic anhydride 5 moles, 반응시간 10시간 그리고 반응온도가 $22^{\circ}C$일 때 흡수능이 가장 좋은 것을 알 수 있었다. 제조된 porous bead에 대하여 증류수 및 생리식염수, 각종 염용액, 인공뇨 및 인공혈액에 대한 흡수도를 검토하였고, 흡수속도 및 보수력에 대한 교환 사항을 검토하였으며, 나아가 가교에 따른 기계적 강도의 변화를 고찰하였다.

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 2003년도 The Korea-Japan Joint Symposium
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• pp.9-10
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• 2003

Cellulose/chitosan and sericin/chitosan blend films with various mixing ratios were prepared and tensile properties, solubilities to the aqueous solution of acetic acid and the degree of swelling by the distilled water were measured. The interaction between the components of blend film and the blending effect were investigated.