• Journal of Hydrogen and New Energy
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• v.22 no.6
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• pp.827-834
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• 2011

Epoxy/graphite/expanded graphite composites have been prepared in various weight ratios and thermal degradation and electrical properties were estimated in order to use for the bipolar plate materials in PEMFC. Thermogravimetric analysis (TGA) showed that the epoxy/graphite system cured by a curing agent GX-533 was most proper because its weight loss until $80^{\circ}C$ at which PEMFC would be operated was 0.3 wt%, and differential scanning calorimetry (DSC) analysis showed its cure temperature would be sufficient at $80^{\circ}C$. The activation energy for the cure reaction was 132.0 kJ/mol and the pre-exponential factor was $1.76{\times}10^{17}min^{-1}$. Electrical conductivity on the surface of the bipolar plate prepared under a pressure of 200 $kgf/cm^2$ was increased from 4 to 25 $S/cm^2$ by increasing expanded graphite (EG) content from 50 phr to 90 phr. The percolation threshold was initiated around 75 phr and the corrosion rate at 80 phr was 1.903 $uA/cm^2$.

• Korean Journal of Pharmacognosy
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• v.24 no.4
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• pp.282-288
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• 1993

Very little utilization of the fruits of Malus baccata(Rosaceae) has been employed for food and medicinal plants except for preparing fruit beverages. But, it was estimated as valuable to investigate the chemical components for the botanical resource of this plant. In this study, it was found that the fruits of this plant contained primary long chain alcohol, ${\beta}-sitosterol$, campesterol, ursolic acid and ${\beta}-_D-glucosides$ of ${\beta}-sitosterol$ and campesterol. However, phloretin(dihydrochalcone) and its 5-O-glucoside(phloridzin) known as plant growth regulators in many Rosaceae plants were not found in this plant material by co-TLC analysis with authentic specimens. Although plant sex hormone, estrone, was often contained in relates of M. baccata, e.g., Prunus spp., Crataegus spp. and Malus spp., this compound was not detected in this fruit by comparison with an authentic material. By RIC chromatography, it was suggested that the Soxhlet extraction by the solvent of ether was excellently useful to extract ursolic acid efficiently.

• Journal of the Korean Society of Food Culture
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• v.25 no.6
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• pp.801-809
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• 2010

This study investigated the quality characteristics of Sulgidduk with different levels (0, 4, 8, 12, 16%) of added yam powder by measuring water content, color value, texture, and sensory quality. The water content of Sulgidduk decreased significantly (p<0.05) by increasing the amount of yam powder. The Hunter's L value of Sulgidduk decreased, and the a and b values increased significantly. Mechanical texture parameters, such as hardness, cohesiveness, gumminess, adhesiveness, and chewiness decreased significantly (p<0.05) as the amount of added yam powder increased. The springiness of the 0, 4, 8 and 12% yam Sulgidduk was not different significantly, but springiness decreased significantly in the 16% yam Sulgidduk. Hardness increased significantly during storage, whereas cohesiveness, gumminess, and adhesiveness decreased. Springiness of the control sample increased significantly, but the Sulgidduk with added yam powder had the highest springiness levels during the first and second days. Chewiness was highest during the first day in all Sulgidduk preparations. The 12% yam Sulgidduk was the best in color, flavor, taste, moistness, chewiness, and overall acceptability from the sensory evaluation. These results indicate that Sulgidduk with 12% added yam powder had the best quality in sensory and texture analyses.

• Journal of Marine Bioscience and Biotechnology
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• v.2 no.3
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• pp.133-141
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• 2007

There are produced more than 600,000 tons of seaweeds every year along the coast of the Korea. Jeonnam province, south-west coast area, of Korea is producing 93% of total amounts of seaweeds. The laver, sea mustard, and tangleweed maintain stability in the output and has been exported as a simple product processing through drying or salting. It was evaluated the low value-added products and limited the expansion for the consumption of seaweeds. The seaweeds contains 40-60% carbohydrate and structurally different compared with land plant. The dietary fiber from seaweeds has been known the function of facilitating the bowl movement, excretion the heavy metal in the body, lowering the blood cholesterol level, anti-coagulant of blood, and anticancer. Especially, brown algae including sea mustard, seaweed fusiforme, and tangleweed contains alginic acid, laminarin, mannitol, fucoidan which are lowering the blood cholesterol level, lowering blood pressure, and fusion of blood clot. Agar-agar, carrageenan, and porphyran compound in red algae are known to antimutagenicity and anticoagulant function. In spite of potential of seaweed as a main bio-resource, there are lack of research to facilitate the consumption with its functional properties and consumers are unsatisfied with simple processing products. Also, the seaweed by-product dump into the sea and cause pollution of the seawater. Therefore, there are needed the scheme to promote the consumption of seaweeds. The development of value-added products, finding functional properties from seaweeds, development the functional feed for animal using seaweed by-products, and utilization of unused algae for food or other industrial uses will increase fisherman's income as well as serve as an aid for the people health due to its functional properties. Using by-product of seaweed and unexploited seaweed are needed to development of bio-degradable food packaging material and functional feed for animal.

• Korean Journal of Food Science and Technology
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• v.47 no.1
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• pp.111-118
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• 2015

In the present study, the phenolic compound level, antioxidant activity, and inhibition of lipid accumulation in Aspergillus oryzae-fermented water extracts of the Platycodon grandiflorum (PG) root and the Curcuma longa (CL) root were determined. Total polyphenol and flavonoid contents were decreased after fermentation. However, the flavonoid content of the fermented PG (FPG) was increased by 2.9-fold that of the PG before fermentation. In addition, the antioxidant activities were significantly decreased following fermentation. The potential anti-obesity activity was assessed by determining lipid accumulation and mRNA expression of sterol regulatory element-binding protein 1c (SREBP-1c) and peroxisome proliferator-activated receptor gamma ($PPAR{\gamma}$) in 3T3-L1 cells. Aspergillus-fermented extracts of PG and CL roots decreased lipid accumulation, and mRNA expression of SREBP-1c and $PPAR{\gamma}$ in 3T3-L1 cells. These results indicate that Aspergillus fermentation augments the anti-obesity activity of PG and CL by regulating the expression of the genes involved in lipid accumulation and cell differentiation of 3T3-L1 cells.

• Microbiology and Biotechnology Letters
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• v.37 no.2
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• pp.140-146
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• 2009

Cyclosporin, an immunosuppressant, is a representative group of biologically active secondary metabolites produced by the fungus Tolypocladium inflatum. The amount and ratio of cyclosporin derivatives in the culture broth are an important factors for the production of cyclosporin A and the purification in the industrial process. Therefore, we studied the effect of amino acids and complex organic nitrogen sources using Tolypocladium inflatum mutants on the productivity of cyclosporin A and the ratio of cyclosporin derivatives. Overproducing mutant YHC-004 having seven times higher productivity than mother strain's could be obtained through the artificial mutation by UV irradiation. The concentration and kind of organic nitrogens and amino acids shows the profound effect on the productivity of cyclosporin A and ratio of cyclosporin derivatives. As a result, it was possible to raise the productivity and the ratio of cyclosporin A up to 3,430 mg/L and 93% respectively, but on the other hand the other cyclosporin derivatives decreased less than 2% in the culture broth.

• Korean Journal of Clinical Pharmacy
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• v.22 no.2
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• pp.123-130
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• 2012

거대세포바이러스(Cytomegalovirus; CMV) 감염은 동종조혈모세포이식 환자의 주요 사망원인 중 하나이다. 용량감소전처치(Reduced-intensity conditioning; RIC)를 이용한 조혈모세포이식은 골수억제전처치(Myeloablative conditioning; MAC)에 비해 골수억제 및 면역억제가 적으므로 CMV 감염 발생율을 감소시킬 것이라 예상되었으나 예방적 면역억제요법, T세포 제거 약제의 사용 등으로 서로 상이한 결과가 보고되고 있다. 2007년 1월부터 2009년 12월까지 총 141명의 환자(MAC 113명, RIC 28명)가 동종조혈모세포이식을 받았으며, CMV 감염은 MAC 62.8%, RIC 57.1% (p = 0.310), CMV 질환은 각각 12.4%, 14.3% (p = 0.785)에서 발생하였다. CMV 감염/질환 발생빈도와 CMV 항원 혈증검사 지속기간, 초기/최고치, 생존율은 두 군간 유의한 차이가 없었다. CMV 감염 위험인자에 대한 다변량분석 결과, 환자가 고령일수록(HR 1.024, 95% CI 1.002-1.045; p = 0.031) 또는 grade 2 이상의 급성 이식편대숙주병이 발생한 경우에(HR 1.849, 95% CI 1.031-3.315; p=0.039) CMV 감염 발생 위험율이 유의하게 높았다. 결론적으로, 전처치요법 강도에 따른 CMV 감염의 발생빈도와 발현양상의 차이는 없었으나, 고령이거나 grade 2 이상의 급성 이식편대숙주병이 발생한 환자의 경우 CMV 감염 발생과 유의한 연관성을 보였다. 이상과 같은 결과에 비춰 봐서 CMV 질환이 대부분 이식 100일 이후에 발생한 점을 고려할 때, 이식 후 CMV 감염 발생 시 ganciclovir 선제요법과 함께 이들 환자들에게 지속적인 모니터링을 실시하는 것이 필요할 것으로 사료된다.

• Nutrition Research and Practice
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• v.7 no.2
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• pp.96-102
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• 2013

Obesity, an intractable metabolic disease, currently has no medical treatment without side effects, so studies have been actively carried out to find natural compounds that have anti-obesity activity with minimum side effects. In this study, the anti-obesity effects of water extracts of seven Capsicum annuum L. varieties being Putgochu (Pca), Oyee gochu (Oca), Kwari putgochu (Kca), Green pepper (Gca), Yellow paprika (Yca), Red paprika (Rca) and Cheongyang gochu (Cca), were examined through the evaluation of lipoprotein lipase (LPL) mRNA expression level in 3T3-L1 cells (mouse pre-adipocytes). After capsaicin elimination by chloroform defatting, freeze-dried powder of Cca was treated to 3T3-L1 cells and anti-obesity effects were examined by determining the LPL mRNA level using the RT-PCR method. Of the primary fractions, only proven fractions underwent secondary and tertiary refractionating to determine anti-obesity effects. From seven different Capsicum annuum L., there was a significant decrease of the LPL mRNA expression level of 50.9% in Cca treatment compared to the control group. A significant decrease of the LPL mRNA expression level was shown in primary fractions (Fr) 5 (36.2% decrease) and 6 (30.5% decrease) of the Cca water extracts. Due to the impurities checked by UPLC chromatography, Fr 5 and 6 were refractionated to determine the LPL mRNA expression level. Treatment of Fr 6-6 (35.8% decrease) and Fr 5-6 (35.3% decrease) showed a significant decrease in the LPL mRNA expression level. When analyzed using UPLC, major compounds of Fr 6-6 and Fr 5-6 were very similar. Subsequently, we refractionated Fr 6-6 and Fr 5-6 to isolate the major peak for structure elucidation. Treatment of Fr 5-6-1 (26.6% decrease) and Fr 6-6-1 (29.7% decrease) showed a significant decrease in the LPL mRNA expression level. Consequently, the fractions may have a possibility to ameliorate obesity through the decrease of the LPL mRNA expression level.

• Applied Chemistry for Engineering
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• v.24 no.5
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• pp.499-506
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• 2013

As the usuage of tempered glass for touch panel increased rapidly with the development of industry, the amount of UV curable coating solution used to protect glass surfaces during a tempered glass manufacturing process increased as well. The UV curable coating has advantages compared to thermal curing such as shortened curing time and non-solvent. Appropriated polymer and monomer were used as an acid polymer to grant an alkali peeling ability. The monomers were 2-hydroxyl methylacrylate, 1,6-hexanediol diacrylate and dipentaerythritol hexaacrylate which have acryl groups of 1, 2, and 6, respectively. The combination of three different types of photoinhibitors were used and bisphenol A epoxy diacrylate was used as an oligomer. In this study, experiments were carried out by controlling the amount of photoinitiator, oligomer, and additive while maintaining the constant content of the acid polymer and the acrylic monomer. The changes in physical properties according to the additive content were investigated. It was found that the combination of photoinitiators was necessary to achieve the hardness above 4H and it was possible to control the delamination type of the coating film from a sheet to pieces by the addition of TPO as an initiator. The increase in oligomer contents increased the hardness and adhesiveness alongside dissection time. Talc content of 20 wt% showed the best results.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.8
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• pp.1175-1182
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• 2013

The purpose of this study was to evaluate the functional characteristics of fermented mixed grain beverages obtained using different microbial species and to evaluate their suitability for consumption. Various fermented mixed grain beverages were prepared through fermentation with Aspergillus (A.) oryzae CF1003 (A), A. acidus KACC46420 (B), Rhizopus (R.) delemar KACC46149 (C), R. oryzae KACC45714 (D), R. oryzae KACC46148 (E), A-E mixed strains (F), A. oryzae CF1001 (G), A. acidus CF1005 (H) and A+H mixed strains (I). The visual appearance, flavor, taste, and the antioxidant capacity of each fermented beverage were then assessed. The chromaticity and aesthetic quality of the fermented beverage was measured and all fermented beverages appeared yellow. The C-, G-, H- and I-fermented beverages received scores of 3.319, 3.206, 3.170 and 3.025 points, respectively, following a sensory evaluation, while the others received less than 3 points. The polyphenol content of the different beverages were similar, while the flavonoid content significantly differed. In particular, the flavonoid content of the C- and E-fermented beverages was significantly higher than other beverages. Although the electron donating ability and reducing power of the fermented beverages was very low, the superoxide dismutase (SOD)-like activity of all beverages (except the E-fermented beverage) increased in a concentration-dependent manner. Specifically, the SOD-like activity from the F-fermented beverage at 10,000 ppm was more than 50%. Interestingly, the antioxidant activities of the beverages were unrelated to their polyphenol or flavonoid levels. This study also found that the aesthetic qualities of G- and H-fermented beverages were the highest and that this was completely independent of their antioxidant capacity. Therefore, our results suggest that further studies are required to develop mixed grain-derived fermented beverages that can also fulfill a useful functional purpose.