• 한국수산과학회지
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• 제31권1호
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• pp.82-89
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• 1998

미역과 큰 다시마 알긴산의 염산 부분가수분해에 의한 저분자화 조건을 구명하였으며, 저분자화가 알긴산의 점성, 용해도, 유화능, 흡유능, 담즙산결합능 및 금속이온결합능 등의 물성에 미치는 영향에 관하여 검토하였다. 미역에서 추출한 알긴산을 시료로 하여 저분자화의 조건을 검토한 결과, 염산에 의한 반응시간의 연장 및 염산의 농도증가와 더불어 구성 polyuronate의 중합도는 급격히 감소하였다. 그리고 0.3N HCl 부분가수분해에 의하여 분자량을 1/100로 감소시키는데 소요되는 반응시간은 약 50분이었고, 이 때 각각의 수율은 약 $75\%\~80\%$ 이었다. 각 알긴산의 M/G의 비는 저분자화에 의하여 증대하였으며, 알긴산 용액의 점성은 저분자화하므로서 급격히 저하하였고, 알긴산의 점도와 분자량은 밀접한 상관관계를 보였다($r^2=0.9890$). 온도단계별 ($5\~40^{\circ}C$)로 측정한 알긴산의 용해도는 수용성 알긴산이 산$\cdot$알칼리가용성 알긴산에 비하여 $7\~12\%$ 높았으며, 저분자화와 더불어 상승하였다. 한편, 저분자화는 유화능의 증가를 가져왔으며, 용해도와는 비슷한 관계를 보였다. 그러나 흡유능과 금속이온결합능은 저분자화에 의하여 감소하였으며, 특히 금속이온결합능에 있어서는 미역 알긴산은 $Pb^{2+},\;Cu^{2+},\;Zn^{2+},\;Co^{2+}$의 순으로, 그리고 큰 다시마 알긴산은 $Cu^{2+},\;Pb^{2+},\;Zn^{2+},\;Co^{2+}$의 순으로 각각 감소하였다. 담즙산결합능은 저분자화와 더불어 오히려 증가하는 특징을 보였다.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2010년도 추계학술대회 초록집
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• pp.163.2-163.2
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• 2010

We developed a simple method to synthesis a nitrogen doped graphene, nitrogen plasma treated graphene (NPG) sheets thought nitrogen plasma etching of graphene oxide (GO). X-ray photo electron spectroscopy (XPS) study of NPG sheets treated at various plasma conditions reveal that N-doping is classified to 3 kinds of binding configurations. The nitrogen doping concentration is at least 1.5 at % and up to 3 at% with changing of ratio of nitrogen configuration in NPG. Our group demonstrate ultracapacitor with high capacity and extremely durable using a NPG sheets that are comparable to pristine graphene supercapacitor, and pseudocapacitor using polymer and metal oxide with redox reaction, capacitance that are three-times higher, and a cycle life that are extremely stable. We also realized flexible capacitor by using the paper electrode that are coated by NPG sheets. NPG paper capacitor presented almost same performance compare with NPG on a metal substrate, and durability is much more enhanced than that. To additionally explain that how different kind of atoms in graphene layers can act as the ion absorption sites, we simulated the binding energy between nitrogen in graphene layer and ions in electrolyte. Increasing the energy density and long cycle life of ultracapacitor will enable them to compete with batteries and conventional capacitors in number of applications.

• Asian-Australasian Journal of Animal Sciences
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• 제16권2호
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• pp.261-265
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• 2003

This study was performed to determine whether transglutaminase (Aciva-TG, TGase) can be used to reduce the salt level in low-fat sausages and to replace emulsified meats (10%) for the manufacture of restructured meat products (RMP). Pork hams and loins were collected from a local retail market in Gwangju, Korea and used for the manufacture of sausages and RMPs, respectively. TGase at the level of 0.1% can permit the reduction of the salt level from 1.5% to 1.0% in low-fat comminuted sausages without any quality defects, however a crumbly texture was found if the salt level was reduced below 1.0% even though it combined with certain amounts of TGase. No differences in chemical composition and physical properties were observed (p>0.05) among treatments. Approximately 0.3% of TGase can replace 10% emulsified meats, which are normally used for improvement of binding capacity to manufacture RMPs, without quality defects. This study suggests that TGase could be used for the manufacture of low-fat, low-salt functional meat products for the improvement of textural characteristics and binding capacity without adverse effects.

• Applied Biological Chemistry
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• 제33권1호
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• pp.39-42
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• 1990

동부 전분의 아밀로오스 특성을 연구하였다. 동부 아밀로오스의 함량은 25.1 %였으며 iodine binding capacity는 20.2 %였다. 동부 아밀로오스의 ${\beta}-amylolysis$ limit는 82.3 %였고, 고유점도는 204ml/g이고 중합도는 1,510 glucose units였다. 겔 크로마토그래피에 의한 아밀로오스의 분자량 분포는 $1{\times}10^4$(0.7 %), $1{\times}10^4{\sim}4{\times}10^4$(4.1 %), $4{\times}10^4{\sim}5{\times}10^5$(44.6 %), $5{\times}10^5{\sim}4{\times}10^7$(49.6%)였고, 동부 아밀로오스와 요오드의 결합에 따른 최대 흡수 파장은 $615{\sim}645\;nm$의 범위였다.

• Bulletin of the Korean Chemical Society
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• 제31권8호
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• pp.2201-2206
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• 2010

To improve the separation property and stability of metal chelate Cu(II) column, three new kinds of multidentate aminocarboxy silica columns with cation-exchange properties were synthesized using glutamic acid (Glu), glutamic acidbromoacetic acid (Glu-BAA), glutamic acid-bromosuccinic acid (Glu-BSUA) as ligands and silica gel as matrix. The standard proteins were separated with prepared chromatographic columns. The stationary phases exhibited the metal chelate property after fixing copper ion (II) on the synthesized multidentate ligand silica columns. The binding capacity of immobilized metal ion was related with the dentate number of multidentate ligands. Chromatographic behavior of proteins and the leakage of immobilized metal ion on multidentate chelate Cu(II) columns were affected by the dentate number of multidentate ligands and competitive elution system directly. The results showed that quinquedentate Glu-BSUA-Cu(II) column exhibited better chromatographic property and stability as compared with tridentate Glu-Cu(II) column, tetradentate Glu-BAA-Cu(II) column and commonly used IDA-Cu(II) column.

• 한국식품조리과학회지
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• 제22권2호
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• pp.173-180
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• 2006

This study evaluated the quality characteristics of dried noodles made of wheat flour with different concentrations of Dioscorea japonica flour. Cooking quality, mechanical texture properties and viscosity were measured, and sensory evaluation was performed with the prepared noodles. Water binding capacity, solubility and swelling power of the composite Dioscorea japonica flour-wheat flours were higher than those of pure wheat flour. Gelatinization points of the composite Dioscorea japonica flour-wheat flours were increased and initial viscosity at $95^{\circ}C$, viscosity at $95^{\circ}C$ after 15 minutes and maximum viscosity of these composites were decreased, with increasing Dioscorea japonica flour content, as measured by amylograph. With increasing Dioscorea japonica flour content, L and b values were decreased, but a value was increased, for the color values, while weight and volume of the cooked noodles and turbidity of the soup were increased. For the textural characteristics, the addition of Dioscorea japonica flour increased the hardness and decreased the adhesiveness, cohesiveness and springiness. Overall, the noodles made with 10% Dioscorea japonica flour were preferred more than the other noodles, as tested by sensory evaluation.

• Journal of Nutrition and Health
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• 제30권8호
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• pp.1009-1017
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• 1997

This study was designed to assess the iron nutritional status and growth development of children provided with and without the national school -lunch program(NLSP). The subjects consisted of 590 elementary school children (313 boys, 277 girls) in the 2nd, 4th and 6th grades provided with (n=390) and without (n=200) NSLP. anthropometric measurements were taken for body weight, height, triceps skinfold thickness and body fat percentage. Nutrient intakes were assessed by a modified 24 -hour recall method. Fastinig blood samples were obtained and analyzed for hemoglobin concentration, hematocrit, serum iron and total iron binding capacity. The results obtained are summarized as follows. No significant differences between children provided with and without NSLP were found in height and body weight, but triceps skinfold thickness and body fat(%) were significantly higher in children without NSLP than in those with NSLP. There was no significant difference in hemoglobin concentration and hematocrit between children provided with and without NSLP. However, serum iron concentration and transferrin saturation were higher in the children provided with NSLP(81.9$\mu\textrm{g}$/dl and 22.8%) than in the children without NSLP(73.1$\mu\textrm{g}$/dl and 20.9%). When comparing iron and vitamin C intakes , iron intake was significantly higher in children provided with school-lunch, but vitamin C intake was significantly higher in children provided without school-lunch. Percentages of iron -deficient anemia in underweight, normal and obese children when judged by total iron binding capacity were 14.9%, 12.5% and 25.8% respectively.

• BMB Reports
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• 제42권3호
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• pp.160-165
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• 2009

The temperate Staphylococcus aureus phage ${\Phi}11$ harbors cI and cro repressor genes similar to those of lambdoid phages. Using extremely pure ${\Phi}11$ Cro (the product of the ${\Phi}11$ cro gene) we demonstrated that this protein possesses a single domain structure, forms dimers in solution at micromolar concentrations and maintains a largely $\alpha$-helical structure even at $45^{\circ}C$. ${\Phi}11$ Cro was sensitive to thermolysin at temperatures ranging from $55-75^{\circ}C$ and began to aggregate at ${\sim}63^{\circ}C$, suggesting that the protein is moderately thermostable. Of the three homologous 15-bp operators (O1, O2, and O3) in the ${\Phi}11$ cI-cro intergenic region, ${\Phi}11$ Cro only binds efficiently to O3, which is located upstream of the cI gene. Our comparative analyses indicate that the DNA binding capacity, secondary structure and dimerization efficiency of thermostable ${\Phi}11$ Cro are distinct from those of P22 Cro and $\lambda$ Cro, the best characterized representatives of the two structurally different Cro families.

• 한국식품과학회지
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• 제23권2호
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• pp.175-182
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• 1991

옥수수 전분을 propylene oxide와 반응시켜 치환도가 $0.031{\sim}0.147$되는 hydroxypropyl 옥수수 전분을 제조하여 물리화학적 특성을 규명하였다. Hydroxypropylation에 의하여 팽윤력, 용해도 및 물결합 능력이 증가하고 생전분의 효소 분해력이 높아졌으며 요오드 흡착강도가 낮아졌다. 아울러 hydroxypropylation에 의하여 전분의 결정화도도 감소되었다. 한편, 옥수수 전분을 hydroxypropylation시켰을 때 분자량 $1.34{\times}10^7$ 이상의 큰 분자는 감소하였고 $1.34{\times}10^7{\sim}1.18{\times}10^5$의 전분 분자는 증가하였다. Hydroxypropylation에 의하여 옥수수 전분 입자의 형태에는 별 변화가 없었으나 입자크기는 평균입경이 $13.9\;{\mu}m$에서 $16.0\;{\mu}m$로 증가하였다.

• Applied Biological Chemistry
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• 제31권3호
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• pp.249-254
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• 1988

아끼바레(일반계), 삼강(다수계), 마하트마(인디카형) 등 세 품종의 쌀 전분에 대해서 인화학적 성질, 호화 양상, 산처리(lintnerization)실험을 하였고 밥의 단단한 정도를 Rheometer로 측정하였다. 물결합 능력과 아밀로오스 함량은 삼강이 가장 컸다. 최고점도와 breakdown은 아끼바레, 삼강, 마하트마 순인 반면 consistency, set back은 마하트마, 삼강, 아끼바레의 순이었다. 산 가수분해는 세 전분 모두 두 단계로 진행되었으며 마하트마 전분의 가수분해율은 아끼바레, 삼강보다 낮았다. 상대적인 결정화도는 마하트마, 아끼바레, 삼강 순으로 높았다. 상대적인 결정화도가 가장 큰 마하트마는 열이나 산처리에 강한 저항을 보였고, 물결합 능력이 작았으며 취반시 더 단단하였다.