• 공업화학
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• 제9권3호
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• pp.451-456
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• 1998

식품가공 공장에서 1차 가공되고 버려지는 게껍질을 화학처리하여 chitin을 제조한 후, 탈아세틸화하여 chitosan(Cs)을 제조하여 이 chitosan에 acrylic acid, maleic acid, fumalic acid를 그라프트공중합시켜 CsAa, CsMa와 CsFa를 합성하였다. 제조한 Cs, CsAa, CsMa와 CsFa의 구조 확인은 FT-IR, 전자현미경, X-Ray회절분석기로 하였으며, 응집제로서의 가능성을 검토하기 위하여 제지공장 폐수를 대상으로 응집제의 투입량을 변화시켜 본 결과 투과도, COD, SS의 제거율이 투입량 40ppm에서 제일 좋았으며, chitosan 보다 그라프트중합체를 사용했을 때의 제거율이 월등히 개선되었다. pH 변화에 따라서는 투과도, COD, SS의 제거율이 pH 5에서 가장 우수한 결과를 나타내었다. Chitosan 보다 그라프트공중합체인 CsAa, CsFa와 CsMa가 월등히 우수한 제거율을 나타내고 있는 것은 chitosan에 카르복시기를 가진 단량체가 공중합됨으로서 양쪽성을 띠기 때문으로 예측된다.

• 대한치과보철학회지
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• 제40권5호
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• pp.525-535
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• 2002

The purposes of this study were to evaluate the adherence of bacteria on various denture base resin materials and effects of chitosan, added to denture base materials on bacterial adherence. PMMA denture base resin such as heat-cured Vertex-RS, self-cured Vertex-SC and 4-META denture base resin such as heat-cured Meta-Dent, self-cured Meta-Fast were used in this study Samples were divided into two groups the denture base resin with chitosan, without chitosan Streptococcus mutans and Lactobacillus casei were used in this study. The surface of samples was observed by SEM. When chitosan was added to M17 and MRS broth, viable cell count of bacteria was reduced. Viable cell count of Streptococcus mutans on the samples decreased as follows : Meta-Dent, Vertex-SC, Meta-Fast, Vertex-RS. Viable cell count of Lactobacillus casei on the samples decreased as follows: Vertex-RS, Meta-Dent, Meta-Fast, Vertex-SC. The resin with chitosan showed lower adherence of bacteria than without chitosan. The images of SEM showed that the surface of the resin with chitosan was rougher than that of without chitosan. These results showed that the denture base resin materials with chitosan have rougher surface than without chitosan, but less bacteria adhered on them.

• 한국작물학회지
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• 제44권4호
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• pp.368-372
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• 1999

The practicality of utilizing chitosan as a natural antimicrobial compound to reduce soybean sprout rot was tested. Domestic and imported soybean seeds were soaked for 6 hours in solutions containing different levels of chitosan and acetic acid (glacial), and cultured at $25^{\circ}C$ for 6 days. In case of domestic seeds, soaking with 1,000ppm chitosan increased germination percentage, hypocotyl thickness, total length, and fresh weight of sprouts by 4%, 5%, 2%, and 1%, respectively. The total sprout yield was increased by chitosan in a concentration-dependent manner in that 1,000ppm chitosan resulted in 8% increment of total yield (7.47kg sprouts/kg seed). Chitosan significantly reduced sprout rot percentage to 7.0% compared to control (13.8%), and consequently enhanced marketable sprout yield by 39%. Compared to domestic seeds, the imported soybean seeds exhibited very low germination percentage regardless of chitosan treatments. Chitosan, nevertheless, consistently induced yield increment and rot decrement in imported soybean sprouts. Although 100ppm acetic acid was effective in reducing sprout rot percentage down to 11.8%, its yield-increasing effects were not as prominent as chitosan. In conclusion, soaking soybean seeds with chitosan seems to be a practical method to enhance the efficiency of soybean sprout production.

• 한국재료학회지
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• 제21권2호
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• pp.125-132
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• 2011

Fibrous chitosan membranes were fabricated as a substrate for skin applications using an electro-spinning process with different solvents and varying concentrations. Scanning electron microscopy (SEM) images confirmed that the formation of the chitosan fibrous membrane in trifluoroacetic acid was better than that in acetic acid. Fourier transform infrared spectroscopy showed that the chitosan fibers were cross-linked with glutaraldehyde, and that the cytotoxicity of the aldehyde groups was reduced by glycine and washing by NaOH and DI water. Chitosan cross-linked fibrous membranes were insoluble in water and could be washed thoroughly to wash away glycine and excess NaOH and prevent the infiltration of other water soluble bio-toxic agents using DI water. MTT assay method was employed to test the cytotoxicity of chitosan membranes during fabricating, treating and washing processes. After the dehydration of cell cultured chitosan membranes, cell attachment behavior on the material was evaluated using SEM method. Effect of the treatment processes on the biocompatibility of the chitosan membranes was shown by comparing of filopodium and lamellipodium of fibroblast cells on grown washed and unwashed chitosan fibrous membrane. The MTT assay and SEM morphology confirmed that the washed chitosan fibrous membrane increased cell attachment and cell growth, and decreased toxicity compared to results for the unwashed chitosan fibrous membrane.

• 한국의류산업학회지
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• 제16권2호
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• pp.319-325
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• 2014

This article describes a method for producing chitosan non-woven fabrics by just hot pressing without the use of a binder. A study has been made of the wet spinning of chitosan fiber. The fibers were rinsed thoroughly in running water and chopped wet into staples of with a length of approximately 5-10 mm. The chopped chitosan staples were dispersed uniformly in water and fabricated using a non-woven making machine. This study examined the formation and the characteristics of chitosan non-woven fabrics manufactured by hot pressing without the use of a binder. The effects of the non-woven fabrication conditions on the thermal, morphological, structural, and physical properties of chitosan non-woven fabric with and without water as a plasticizer were studied. The temperature of the exothermic peak, decomposition of chitosan fibers increased with increasing heating rate. Water in the chitosan fiber effectively plasticized the chitosan fiber. The thermal bonded structure of the wet chitosan fiber with water as a plasticizer was clearly found in many parts of the non-woven fabric at a fabrication temperature of $200^{\circ}C$. The intensity and profile of the (100) plane($2{\theta}=10.2^{\circ}$) and (040) plane($2{\theta}=20.9^{\circ}$) in the chitosan non-woven fabric decreases and became smooth in the non-woven fabric formation by melting.

• 패션비즈니스
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• 제10권2호
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• pp.18-26
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• 2006

In this study, the effects of chitosan pre-treatment on the mordanting effect and dyeability were investigated in the dyeing using Japanese pagoda tree. The chitosan treatment effects were evaluated mainly focused on the colors after dyeing of cotton and nylon fabrics which were treated with acidic aqueous solution of chitosan. In the case of chitosan untreated fabrics, the mordanting effects on the cotton and nylon were insignificant and the dyeability was very low. Regardless of the mordant types(Al, Sn, and Fe), the dyed fabrics exhibited almost identical yellowish colors. In the case of chitosan treated fabrics, dark colors were obtained compared to the case of chitosan untreated and ${\Delta}E$ values were increased significantly. In cotton fabrics, the most excellent result was obtained under the condition of unmordanted and chitosan treated fabrics. This verifies the fact that routin coloring matters establish direct linkages with the chitosan components, which exhibit cationic nature, easily. In nylon fabrics, the effects of mordanting treatment and chitosan treatment are so insignificant that the routin coloring matters are presumed to establish direct dyeing with the nylon molecular chains.

• 복식문화연구
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• 제13권4호
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• pp.576-588
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• 2005

The effect of chitosan pretreatment on the dyeing of cotton fiber and silk fiber was investigated. However, it has been difficult to evaluate the effect of the chitosan precisely, since the characterization of the molecular weight and effect of the degree of deacetylation were not elucidated for the application. The treatment effect may change diversely since the chitosan solution viscosity differs a lot based on the chitosan molecular weight. In this study, three chitosan specimens, varying in molecular weight, were applied for the fabric pretreatment in order to investigate the effect of chitosan molecular weight. Also, in order to maximize the efficacy of the chitosan, highly deacetylated chitosan specimens, meeting the deacetylation degree of $100\%$, were selected far the application. The air-permeability change according to the chitosan molecular weight change, influence on the mordanting, color change, and wash fastness change were investigated.

• 한국미생물·생명공학회지
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• 제24권5호
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• pp.546-552
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• 1996

The applicability of chitosan, a biodegradable natural polymer, as the coating material to prevent the dispersal of the spores of the apple white rot agent Botryosphaeria dothidea, was investigated. The physical properties of mixed chitosan/polyvinyl alcohol(PVA) film showed the increased physical properties for film formation, such as tensil strength, elongation, and viscosity, compared to either chitosan or PVA film. The FT-IR spectra of chitosan/PVA film indicated that the film was formed by simple blending not by any new synthetic bond. The chitosan and chitosan/PVA film showed effective antifungal activity on B. dothidea. The formed films were well decomposed by ASTM strains used for biodegradability test, on the other hand, the PVA film could not be decomposed by above standard strains. The field test at apple orchard showed that the dispersal of B. dothidea spores could be effectively reduced by coated film, especially by chitosan/PVA film. The spore dispersal was reduced upto 97.0% by 1.0% chitosan/5.0% PVA film during 4 months.

• 식품과학과 산업
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• 제53권1호
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• pp.56-68
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• 2020

Recently, chitosan has increased attention in commercial applications in the food industry in terms of its biocompatibility and nontoxicity. In particular, chitosan has been used as a good hosting material for producing nanoparticles due to its unique property of ionic gelation. Chitosan has disadvantages such as low solubility at physiological pH, causing the metabolism of core material in the intestine and gastric juice. To overcome these limitations, various chitosan derivatives such as carboxylated, thiolated, and acylated chitosan have been studied. This review focuses on the changes in the physicochemical properties of chitosan nanoparticles with the introduction of hydrophobic groups, the application of functional nanocapsules as coatings, and their applicability in the food sector. The physicochemical modification of chitosan is expected to be an attractive research field for the development of chitosan applications for food as well as for improving bioavailability in functional food.

• 대한방사성의약품학회지
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• 제7권2호
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• pp.113-118
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• 2021

Chitosan is a polysaccharide derived from chitin by deacetylation. Chitosan is non-toxic, biodegradable, and biocompatible, so that it can be used in wide variety of medical applications such as wound healing and antimicrobial biomaterials. It also used as dermal fillers due to its ability to inject with liquid formulations. For investigation on in vivo distribution of these chitosans, Bolton-Hunter-conjugated chitosan (Chitosan-BH) was synthesized by the reaction between the primary amino group of chitosan and N-hydroxysuccinimide ester group of Bolton-Hunter reagent. Then Chitosan-BH was radiolabeled with ¹²⁵I (Chitosan-BH-¹²⁵I) using a Chloramine-T method. The effects of each radiolabeling step on the radiolabeling yield of the final product were tested. The results showed that purification step had significant effects on the radiolabeling yield of the final product. Finally, SPECT/CT images were obtained to evaluate in vivo uptake of the radiolabeled chitosan (Chitosan-BH-¹²⁵I) in several organs. The highest uptake was found in the site of injection at 21 days post-injection. The results of this study suggest that chitosan is expected to be useful for biomaterials of dermal fillers.