• Analytical Science and Technology
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• v.12 no.4
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• pp.306-311
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• 1999

Changes of silk protein compositions of average molecular weight (Mw) and free amino acid composition to different solubility conditions were studied by SDS-polyacrylamide electropholesis, gel permeation chromatography (GPC), and free amino acid analysis method. We can not detected average molecular weight distribution of different hydrochloric acid (HCl) conditions as SDS-polyacrylamide method, but as using GPC method, molecular weight distribution of 2N-HCl, 1N-HCl and 0.5N-HCl (3 hrs at $110^{\circ}C$ treated) are confirmed Mw 800, 1,500 and 3,700, respectively. The average molecular weight of calcium chroride and calcium chloride-enzyme treated samples are shown Mw 46,800 and 12,500, respectively. The degree of hydrolysis and the composition of the free amino acid in the fibroin hydrolysates effected significantly composition of free amino acids of the fibroin powder. The increase of the degree of hydrolysis and ratio of free amino acids and oligopeptides were found to be directly related to the concentration of hydrochloric acid and treatment of enzyme, resulting in the increase of water solubility.

• Korean Journal of Agricultural Science
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• v.43 no.1
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• pp.109-115
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• 2016

Silk has had a reputation as a luxurious and sensuous fabric but it is not popular due to the expensive price and poor durability. To develop the silk materials that apply the various industries, the artificially synthesized gene can be introduced into the silkworm and expressed in the silk gland. Transgenic silkworms for the mass production of green fluorescent silks are generated using a fibroin H-chain expression system. For commercial use, safety assessment of the transgenic silkworms is essential. The purpose of this study was to examine the potential acute oral toxicity of EGFP protein expressed in genetically modified (GM) fluorescence silkworm and to obtain the approximative lethal dose in the male and female at 6-weeks ICR mice. EGFP protein was fed at a dose of 2,000 mg/kg body weight in five male or five female mice. Mortalities, clinical findings and body weight changes were monitored for 1, 3, 7, 14 days after dosing. At the end of 14 day observation period, all mice were sacrificed, and the postmortem necropsy were performed. The test group was not observed death case. Also the effect was not admitted by test substance administration in common symptoms, the body weight and postmortem. The results of single-dose oral toxicity test showed that approximative lethal dose of EGFP protein expressed in fluorescence silkworm was considered to exceed the 2,000 mg/kg body weight in both sexes.

• Polymer(Korea)
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• v.37 no.6
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• pp.717-721
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• 2013

Biomaterials like silk fibroin (SF) and poly(vinyl alcohol) (PVA) have received increasing attention in biomedical applications because of their attractive properties such as hydrophobicity and biocompatibility. In this study, efficient systems consisting of interpenetrating SF/PVA hydrogels were prepared as potential candidate for wound dressing applications. A simple approach consisting of sonication and a freezing-thawing technique was adopted to fabricate the hydrogels. Different blend ratios consisting of SF (100, 75, 50, 25 and 0%) with respect to the weight of PVA were prepared. The produced hydrogels were characterized for physico-chemical investigations using various states of techniques like; FE-SEM, TGA, FTIR and tensile strength. The addition of PVA to SF was proved to be beneficial in terms of reducing the pore size and swelling ratio of hydrogels. The mechanical property of SF had been increased by addition of PVA. These results show that SF/PVA hydrogels may serve as potential candidates for wound dressing application.

• Proceedings of the Korean Society of Sericultural Science Conference
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• 2003.10a
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• pp.109-111
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• 2003

In the present study, we examined ceramide-induced neuronal cell death and its mechanism and process using SK-N-KH cells, and investigated whether ROS was produced and related to other factors. In addition, we tried to check whether silk fibroin had protective effect fur neuronal cells, and through which cell death process this protective mechanism functioned. (omitted)

• 한국약용작물학회:학술대회논문집
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• 2008.11a
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• pp.449-450
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• 2008

• Proceedings of the Korean Society of Sericultural Science Conference
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• 2005.04a
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• pp.43-43
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• 2005

• Proceedings of the Korean Society of Sericultural Science Conference
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• 2005.04a
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• pp.42-42
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• 2005

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.46-47
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• 2006

Vascularization is essential for success in regenerative medicine. We have developed in vitro models to study how human microvascular endothelial cells (EC) and endothelial progenitor cells (EPC) colonize polymer scaffolds and express the endothelial phenotype, including angiogenesis. Examples are given of supportive growth and differeniation of EC on microfibre meshes of the silk protein fibroin and blends of starch with poly(epsilon-caprolactone), phenotypic markers being studied at both protein and mRNA level. Experimental models are also shown and concepts discussed to investigate how the stem cell niche, including that responsible for vascularization could be targeted, for example, by using engineered biodegradable polymer nanoparticles.

• Textile Coloration and Finishing
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• v.7 no.1
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• pp.65-71
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• 1995

Wool yarns were treated in dimethylformamide solutions containing various concentrations of three dibasic acid anhydrides : succinic, itaconic, and phthalic anhydrides in various conditions. The structural aspects of these dibasic acid anhydrides are different : the succinic, itaconic, and phthalic acid anhydrides have saturated aliphatic etylene, unsaturated aliphatic vinyl and aromatic phenyl groups, respectively. The reaction mechanism of the acylation of wool keratin and some resction conditions were invastigated. And the results are as follows. 1. The N-acylation and formation of free carboxyl group were dominant rather than the O-acylation cross-linked on the side chain of polypeptide. The acylation of wool keratin is easier than that of silk fibroin. 2. The higher molecular weight, steric hinderance and resonance caused lower acylating reactivity. By the determination of acyl contents for acylated keratin, it was rerealed that the degree of acylation was succinic acid anhydride > itaconic acid anhhydride > phthalic acid anhydride.

• Proceedings of the Korean Society of Sericultural Science Conference
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• 2004.10a
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• pp.47-47
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• 2004