• 약학회지
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• 제41권4호
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• pp.421-432
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• 1997

A new lectin was partially purified from starfish,Asterina pectinifera by means of physiological saline extraction, salt fractionation, ion exchange chromatography and hy droxyapatite chromatography, and it was named APL. The biochemical properties of the APL were characterized. In addition, its effects on lymphocyte mitogenicity and cancer cell agglutinability were tested. The APL agglutinated nonspecifically human erythrocytes and rabbit blood cells. Agglutinability was decreased to 30% of control activity below pH 5 and above pH 9 and was relatively unstable at increasing temperatures above 60$^{\circ}C$. The activity was reduced by addition of two kinds of metal ions, $Ba^{2+},\;Mn^{2+}$ and chelating agent, EDTA. APL was proved to be glycoproteins containing 9% sugars. For carbohydrate specificity, it was found that the activity of APL was inhibited by D(+)-glucosamine, D(+)-galactosamine, stachyose, N-acetyl-galactosamine and methyl-${\alpha}$-D-galactopyranoside among 35 sugars tested. In amino acid composition, the contents of acidic amino acids such as aspartic acid and glutamic acid were relatively high. This result suggest that the isoelectric point would be in a lower range. APL was found that it promotes the division of human lymphocytes. APL was proved to be a potent agglutinin for cancer cells such as HeLa, L929 and L1210 cells. Significant changes on the HeLa cell surfaces affected by APL were observed under the electron microscope.

• Journal of Animal Science and Technology
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• 제63권6호
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• pp.1301-1313
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• 2021

This study investigated the effects of applying cellulase and starch on the fermentation characteristics and microbial communities of Napier grass silage after ensiling for 30 d. Three groups were studied: No additives (control); added cellulase (Group 1); and added cellulase and starch (Group 2). The results showed that the addition of cellulase and starch decreased the crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF) and pH significantly (p < 0.05) and increased water-soluble carbohydrate (WSC) content (p < 0.05). The addition of additives in two treated groups exerted a positive effect on the lactic acid (LA) content, lactic acid bacteria (LAB) population, and lactic acid / acetic acid (LA/AA) ratio, even the changes were not significant (p > 0.05). Calculation of Flieg's scores indicated that cellulase application increased silage quality to some extent, while the application of cellulase and starch together significantly improved fermentation (p < 0.05). Compared with the control, both additive groups showed increased microbial diversity after ensiling with an abundance of favorable bacteria including Firmicutes and Weissella, and the bacteria including Proteobacteria, Bacteroidetes, Acinetobacter increased as well. For alpha diversity analysis, the combined application of cellulase and starch in Group 2 gave significant increases in all indices (p < 0.05). The study demonstrated that the application of cellulase and starch can increase the quality of Napier grass preserved as silage.

• Journal of Nutrition and Health
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• 제26권6호
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• pp.661-671
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• 1993

The change in fatty acid composition in brain tissue of the second generation rats(Sprague-Dawley strain) was studied using four different fat diets(Corn oil=CO, Soybean oil=SO, Perilla oil=PO, Fish oil=FO, 10% by Wt). The experimental diets were started from pregnancy in four different groups, each consisting of 9 rats. The seound generation rats were fed the same diet as their mothers. Animals were anesthetized with ether at 0, 3, 9 & 16 weeks of age. Whole brains were dissected out, brain tissues were, then, homogenized and lipids were extracted from brain tissues. The fatty acid compositions were measured after methylation by gas-liquid chromatography at 0, 3, 9 and 16 weeks of age of offspring. The changes in the relative concentrations of polyunsaturated fatty acids(PUFA) or more specifically docosahexaenoic acid(22 : 6, $\omega$3, DHA), the major $\omega$3 fatty acid component in rat brain at different age were similar to changes in the amount of DNA in brain tissue showing the maximum value during the lactation. The changes in saturated fatty acid(SFA) content showed a contrasting patten to those of PUFA, while monounsaturated fatty acid(MUFA) increased steadily throughout the experimental period. At birth, the relative concentrations of $\omega$3 series fatty acids the relative concentrations of PUFA, MUFA and SFA converged to very similar values respectively regardless of the dietary fatty acid compositions. In brain tissue, it is of value to note that while changes in relative concentrations of linoleic acid (18 : 2, $\omega$6, LA) and arachidonic acid(20 : 4, $\omega$6, AA) showed a precursor-product-like relationship, $\alpha$-linolenic acid(18 : 3, $\omega$3, $\alpha$-LnA) and DHA showed a different pattern. Even when the $\omega$3 fatty acid content in very low in maternal diet(CO), the second generation rat brain tissues appeared to secure DHA content, suggesting an essential role of this fatty acid in the brain. The fact that a large amount of $\alpha$-LnA in the maternal diet did not have a significant effect on the second generation rat brain $\alpha$-LnA content, indicated that DHA seemed essential component for the brain development in our experimental condition. In all groups, the relative content of $\alpha$-LnA in the brain tissues remained relatively constant throughout the experimental period at the very low level. The study of the specific concentrations and essential role(s) of DHA in each parts of brain tissue is needed in more details.

• Journal of Nutrition and Health
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• 제25권7호
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• pp.555-568
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• 1992

This study was to compare the effects of dietary n-6 and n-3 fatty acids and fat unsaturation on plasma lipids and chemical composition of VLDL and LDL fraction and lipogenic enzymes activity in rat liver under the conditions providing 1) a similar amount of n-6, n-3 fatty acids(LA, ALA, EPA+DHA) in diets and 2) the various degree of fat unsaturation. Male Sprague-Dawley rats weighing 420g were treated for 6-n with six experimental diets providing 25% of energy as fat and which were different only in fatty acid composition. The fats used for a source of each fatty acid were beet tallow for saturated fatty acid corn oil for n-6 linoleic acid(LA) perilla oil for n-3 $\alpha$-linolenic acid(ALA) and fish oil n-3 eicosapentaenoic acid (EPA) and n-3 docosahexaenoic acid(DHA). Plasma cholesterol level was increased by corn oil to compare with beef tallow but was decreased by perilla oil or fish oil. Plasma TG level was significantly decreased by perilla oil or fish oil. Fish oil significantly reduced the level of HDL-Chol and the proportion of Chol in LDL fraction and that of TG in vVLDL fraction. Overall there was a singificant negative correlation between the level of each plasma lipid(Chol TG, VLDL-TG, LDL-C) and the degree of fat unsaturation. However this rerlationship is not always true when compared the hypolipidemic effect of each fatty acid at a similar level of fat unsaturation. There was a trend such taht glucose 6-P dehydrogenase 6-phosphogluconate dehydrogenase and malic enzyme activites were reduced by n-3 fatty acids. Perilla oil significantly increased the incorporation of c20:5 and c22:5 into liver tissue and fish oil suignificantly increased the incorporation of c20:5, c22:6 into liver tissue and the effect of long chain n-3 fatty acid incorporation was greater by fish oil. therefore the hypotriglyceridemic effect of n-3 fatty acid could be resulted from the interference of hepatic lipogenesis by long-chain n-3 fatty acids and the reduced proportion of TG in VLDL fraction and its effect was greater by n-3 EPA+DHA than n-3 ALA even though plasma Chol and TG levels were also influenced by the degree of dietary fat unsaturation.

• 보존과학회지
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• 제6권1호
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• pp.15-30
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• 1997

전남지역 도요지에서 출토된 토기, 시유도편, 녹청자와 청자편의 제조기술과 산지추정은 X선회절분석, 유도결합 플라즈마 발광분석, 열기계적 분석을 통한 물리화학적 성질의 검토로 이루어졌다. 도편의 사용원료는 점토, 석영, 장석광물로 유사하지만 그 함량비는 출토지에 따라 약간의 차이가 있으며, 철분함량에서 토기, 흑갈유, 녹갈유 도편은 $4\~7\%$, 녹청자 및 청자편은 $2\~3\%$로 기종에 따라 두드러진 차이를 나타내고 있다 흑갈유, 녹청자의 구성광물은 $\alpha-Quartz$, mullite와 일부 tridymite, cristobalite로 이루어졌으며, 청자는 $\alpha-Quartz$, mullite만으로 구성되어 있다. 도편의 소성온도는 토기가 $1000\~1100^{\circ}C$, 흑갈유, 녹갈유, 녹청자 청자가 $l130\~1200^{\circ}C$ 정도로 추정되었다. 도편에 대한 출토지의 구분은 분석된 21개의 미량원소중 14개의 원소가 매우 근접되어 불가능하였으며, 도자기제조에 사용된 원료의 지질학적인 특성이 유사한 것으로 판단하였다. 이들 지역에서 출토된 도편의 특성원소는 Rb, Sr, V, Zr, Y, Nd, Sc, La, Ce, Nb, Sm, Eu, Dy, Yb로 14개이다. 영암의 도편은 Zn과 Fe원소에 의해 다른 지역에서 출토된 도편들과 명확히 구분되었고, 출토지가 다른 녹청자, 청자편은 동일한 범위에 군집되는 특징을 나타내어 사용원료가 비슷한 것으로 추정된다.

• 한국식품영양과학회지
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• 제42권7호
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• pp.1015-1021
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• 2013

창과감초(Glycyrrhiza inflata Batal)는 한약재의 조화를 돕고 해독, 항염증, 항궤양 등의 약리작용으로 한방에서 널리 이용되는 약용식물이다. 본 연구에서는 지방세포와 조골세포에서 감초의 생리활성을 확인하고자 감초에탄올추출물(GBE)을 이용하여 세포분화 촉진여부를 조사하였다. GBE의 세포독성여부를 통해 안전하다고 확인된 $1{\sim}30{\mu}g/mL$의 농도 내에서 실험이 진행되었고 지방세포 분화조건에서 다분화능 세포 C3H10T1/2과 지방전구세포 3T3-L1의 Oil Red O 염색을 통해 GBE의 지방세포분화 촉진효과를 확인할 수 있었다. 또한 지방세포의 핵심전사조절인자인 $PPAR{\gamma}$와 그의 표지유전자 aP2, AdipoQ, $C/EBP{\alpha}$의 발현량 증가를 통해 GBE의 지방세포분화 촉진효과를 재확인하였다. 이와 일관된 결과로서 조골세포 분화조건에서 다분화능 세포 C3H10T1/2과 조골전구세포 MC3T3-E1의 ALP 염색을 통해 GBE의 조골세포분화 촉진효과를 확인하였고 조골세포 표지유전자인 ALP, RUNX2, osterix, collagen의 발현량 증가를 통해 GBE의 조골세포분화 촉진효과를 재확인하였다. 이에 따라 본 연구에서는 GBE의 지방세포와 조골세포 분화효과를 매개하는 감초의 구성성분을 조사하기 위해 GA(glycyrrhizic acid)와 LA(licochalcone A)의 분화촉진 여부를 확인한 결과, GA는 영향을 주지 않으나 LA가 GBE의 세포분화효과를 매개한다고 사료된다. 따라서 본 연구에서는 제2형 당뇨와 그에 수반되는 골질환과 골다공증에 대한 치료 소재로서 GBE와 그의 생리활성을 매개할 수 있는 LA의 가능성을 보았으며 GBE에서 분리되는 다양한 화합물의 동정 및 생리활성 효과, LA와의 상승효과 등의 추후 연구가 기대된다.

• 한국전기전자재료학회논문지
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• 제31권5호
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• pp.307-312
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• 2018

Liquid phases in ZnO varistors cause more complex phase development and microstructure, which makes the control of electrical properties and reliability more difficult. Therefore, we have investigated 2 mol% $CaCO_3$ doped $ZnO-Co_3O_4-Cr_2O_3-La_2O_3$ (ZCCLCa) bulk ceramics as one of the compositions without liquid phase sintering additive. The results were as follows: when $CaCO_3$ is added to ZCCLCa ($644{\Omega}cm$) acting as a simple ohmic resistor, CaO does not form a secondary phase with ZnO but is mostly distributed in the grain boundary and has excellent varistor characteristics (high nonlinear coefficient ${\alpha}=78$, low leakage current of $0.06{\mu}A/cm^2$, and high insulation resistance of $1{\times}10^{11}{\Omega}cm$). The main defects $Zn_i^{{\cdot}{\cdot}}$ (AS: 0.16 eV, IS & MS: 0.20 eV) and $V_o^{\bullet}$ (AS: 0.29 eV, IS & MS: 0.37 eV) were found, and the grain boundaries had 1.1 eV with electrically single grain boundary. The resistance of each defect and grain boundary decreases exponentially with increasing the measurement temperature. However, the capacitance (0.2 nF) of the grain boundary was ~1/10 lower than that of the two defects (~3.8 nF, ~2.2 nF) and showed a tendency to decrease as the measurement temperature increased. Therefore, ZCCLCa varistors have high sintering temperature of $1,200^{\circ}C$ due to lack of liquid phase additives, but excellent varistor characteristics are exhibited, which means ZCCLCa is a good candidate for realizing chip type or disc type commercial varistor products with excellent performance.

• 한국식품위생안전성학회지
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• 제22권3호
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• pp.151-158
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• 2007

동치미로부터 분리한 유산균 (68 균주) 중 Escherichia coli O157에 대한 항균 효과를 나타내는 균주는 Lactobacillus plantarum K11로 동정되었다. 분리균주 La. piantarum K11이 생산한 박테리오신의 항균 활성은 대수증식기 후반부에 12,800 BU/mL로 최대 활성에 이르렀다. 항균 활성은 pepsin, protease, proteinase K, papain, chymotrypsin 및 trypsin 처리에 의해 완전히 소실되었으나, catalase, ${\alpha}-amylase$, lysozyme 및 lipase에 의해서는 영향을 받지 않았으므로 단백질성 물질임을 확인하였다. 게다가, 이 활성은 pH 3.0-9.0의 조건하에서나 -20, 4 및 $25^{\circ}C$에서 30일간의 저장 동안에도 안정하였다. 또한 $100^{\circ}C$에서 30분간 가열처리에도 비교적 안정한 편이었고, chloroform이나 hexane 처리에도 활성에 변함이 없었다. 분리 균주의 박테리오신은 Bacillus spp., Listeria spp. 및 Staphylococcus spp. 등의 일부 식중독균의 억제효과는 나타나지 않았으나, Enterobacter aerogenes와 E. coli 등의 장내세균의 억제에는 효과적이었으며, 특히 640 BU/mL의 박테리오신 처리에 의해서 10시간 배양만에 E. coli O157이 완전하게 사멸되었다.

• Journal of Microbiology and Biotechnology
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• 제9권1호
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• pp.106-112
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• 1999

The therapeutic potential of phosphodiesterase 4(PDE4) inhibitors in inflammatory diseases including some autoimmune diseases has been explored recently with some hopeful results. These PDE4 inhibitors are thought to show their anti-inflammatory effect by down-regulating tumor necrosis factor-a (TNF-$\alpha$) production in lymphocytes and macrophages. A high concentration of TNF-$\alpha$has been found in rheumatoid arthritis (RA) synovium and reducing TNF-$\alpha$using biological agents was proven to be an effective RA treatment. To test the possibility of using PDE4 inhibitors for RA treatment, the effects of a newly synthesized PDE4 inhibitor, DWP205505, on TNF-$\alpha$ and IL-10 production was tested in cells isolated from normal peripheral blood and rheumatoid arthritis synovial fluid. Cytokine production was assayed at the protein level by sandwich enzyme-linked immunosorbent assay (ELISA) and at the mRNA expression level by semi-quantitative RT-PCR. Another PDE4 inhibitor, RP73401, was used for comparison. DWP205505 and RP73401 had no harmful effect on cell viability up to 10 $\mu$M concentration during the 24 h culture period. DWP205505 as well as RP73401 significantly reduced TNF-$\alpha$ secretion from lipopolysaccharide (LPS)-stimulated peripheral blood mononuclear cells (pBMC) and synovial fluid mononuclear cells (SFMC). The effect of DWP205505 or RP73401 treatment on the mRNA expression of TNF-$\alpha$ was also studied in LPS-stimulated PBMC and SFMC. TNF-$\alpha$ mRNA expression was increased by LPS stimulation and both of the PDE4 inhibitors suppressed TNF-$\alpha$ mRNA expression. For interleukin-l0 (IL-l0), a little different results were obtained from PBMC and SFMC; IL-l0 secretion was unaffected by LPS stimulation and only minimally affected by both of the PDE4 inhibitors in PBMC. In unstimulated SFMC, DWP205505 and RP73401 slightly enhanced IL-10 secretion, while they reduced IL-l0 secretion from LPS-stimulated SFMC where IL-l0 secretion was a lot higher than unstimulated SFMC. These results suggest that the newly synthesized PDE4 inhibitor DWP205505 may have anti-rheumatoid arthritis activity.

• 대한화학회지
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• 제28권4호
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• pp.210-216
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• 1984

MeOH-MeCN 혼합용매의 Taft용매 파라미터인 ${\pi}^{\ast}$(용매의 polarity-polarizability), ${\alpha}$(용매의 수소결합 주게 산도) 그리고 ${\beta}$(용매의 수소결합 받게 염기도)를 여러 지시약을 사용하여 분광용매화 비교법으로 구하였다. 또한 Swain의 용매 파라미터인 A(음이온을 용매화 시키는 척도)와 B(양이온을 용매화 시키는 척도)를 반응속도 자료를 이용하여 최소 자승법으로 구하였다. 용매 상수 ${\beta}$는 용매의 염기도에 의존하며 혼합용매의 MeOH 함량이 증가할 수록 $(MeOH)_n$의 기여에 의해 증가하는 것을 알 수 있었다. ${\pi}^*$는 용매의 쌍극자 모멘트에 의존하며 혼합용매의 MeCN 함량이 증가할 수록 ${\pi}^{\ast}$값도 커지며 ${\alpha}$는 MeOH의 수소결합주게 효과에 의해 혼합용매의 MeOH함량이 증가할 수록 크게 증가하는 것을 나타냈다. 앞서 보고된 반응들에 용매 파라미터를 적용하여 반응상수를 구하였으며 Taft의 반응상수 a, s와 Swain의 반응상수 a, b사이에는 용매 척도의 차이 때문에 서로 연관성이 없었다. 그러나 그들의 비인 a/s와 a/b는 서로 좋은 직선관계를 보여 주었으며 이들 반응상수 비를 이용하여 반응 메카니즘이나 치환기 변화 및 이탈기 변화에 미치는 용매효과를 논의 하였다.