• Preventive Nutrition and Food Science
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• 제4권2호
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• pp.145-151
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• 1999

Apolipoprotein B-100 (apo B-100) is an important component in plasma low density lipoproteins (LDL). It function as the ligand for the LDL receptor in peripheral cells. The LDLs are removed from the circulation by both high-affinity receptor-mediated and receptor-independant pathways. LDLs are heterogeneous in their lipid content, size and density and certain LDL subspecies increase risk of atherosclerosis due to differences in the conformation of apo B in the particle. In the present study , surface and core peptide fraction of Apo B-100 have been characterized by comparing peptide-mapping and fluorescence spectroscopy. Surface fragments of apo B-100 were generated by digestion of LDL with either trypsin , pronase, or pancreatin elastase. Surface fractions were fractionated on a Sephadex G-50 column. The remaining core fragments were delipidated and redigested with the above enzymes, and the resulting core peptides were compared with surface peptides. Results from peptide-mapping by HPLC showed pronase-digestion was more extensive than trypsin -digestion to remove surface peptide fraction from LDL. Fluorescence spectra showed that core fractions contained higher amount of tryptophan than surface fractions, and it indicated that core fraction wa smore hydrophobic than surface fractions. A comparison of the behavior of the core and surface provided informations about the regions of apo B-100 involved in LDL metabolism and also about the structural features concerning the formation of atherosclerosis.

• KSBB Journal
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• 제29권5호
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• pp.343-352
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• 2014

In the present study, antioxidant activities of two crude pigments (acetone and MeOH) and their solvent fractions (n-hexane, 85% aq.MeOH, n-BuOH, and water fractions) from red crab shell were evaluated by measuring 1,1-diphenyl-2-picryl hydrazyl (DPPH), peroxynitrites, and degree of production of reactive oxygen species (ROS) in HT 1080 cells as well as the extent of oxidative damage of genomic DNA purified from HT 1080 cells. From comparative analysis, 85% aq.MeOH fraction showed the strongest scavenging effect on both peroxynitrite in vitro and intracellular ROS in HT 1080 cells. Protective activities of these samples against hydroxyl radical-mediated genomic DNA damage were also investigated. 85% aq.MeOH and n-BuOH fractions significantly inhibited oxidative damage of purified genomic DNA. On the other hand, we investigated their inhibitory effects on nitric oxide (NO) production in lipopolysaccharide (LPS)-stimulated Raw 264.7 cells. All samples significantly reduced NO production. Among the samples, n-hexane and water solvent fractions most effectively inhibited NO.

• 대한수학교육학회지:학교수학
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• 제7권2호
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• pp.103-121
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• 2005

이 연구에서는 남북한, 중국, 일렬의 초등학교 수학 교과서를 비교$\cdot$분석하여 분수 나눗셈 알고리즘 도입을 위한 교재 구성 및 학습 지도의 개선 방향을 제안하고자 한다. 이를 위해 먼저 분수 나눗셈 알고리즘의 의미를 '포함제', '단위비율 결정', '비 또는 측정 단위 세분', '곱셈의 역연산', '분수의 곱셈으로부터의 유추'의 다섯 맥락에서 살펴보았다. 이어 북한, 중국, 일본 그리고 우리나라 초등학교 수학 교과서의 분수 나눗셈 알고리즘 도입 및 전개 방법의 특징을 분석하였다. 이러한 분석으로부터 얻은 시사점은 다음의 다섯 가지이다. 첫째, 제수의 역수의 의미와 제수의 역수를 곱하는 의미를 명확하게 드러내도록 다루어야 한다. 둘째, 분수 나눗셈을 단위비율 결정 맥락에서 도입하는 방안을 검토하여야 한다. 셋째, 현재 <7-가 단계> 용어인 '역수'를 <6-나 단계> 분수의 나눗셈 지도 장면에서 제기하거나, 적어도 역수의 의미가 드러나도록 지도하여야 한다. 넷째, 분수 나눗셈은 다양한 맥락에서 풍부한 의미로 전달되어야 한다. 끝으로 <5-나 단계>, <6-나 단계>에 걸쳐 여러 지엽적인 주제로 세분되어 있는 현재의 분수 나눗셈 단원 구성은 포괄적이고 통합적인 방식으로 구성하여야 한다.

• Advances in Traditional Medicine
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• 제7권5호
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• pp.477-484
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• 2008

The present study was aimed at investigating the hypouricemic and xanthine oxidase inhibitory activities of the various fractions of the hydromethanolic extract of the leaves of Coccinia grandis L. Voigt (Cucurbitaceae). The leaves of this species was used in traditional medicinal system for the treatment of gout, rheumatism, jaundice, bronchitis, fever, skin eruptions, wounds, etc. The degree of xanthine oxidase inhibition was determined in vitro by measuring the increase in absorbance at 295 nm associated with uric acid formation. Among the fractions tested, the chloroform fraction exhibited highest potency ($IC_{50}$ $17.8\;{\mu}g/ml$). This was followed by the pet-ether ($IC_{50}$ $29.7\;{\mu}g/ml$), ethyl acetate ($IC_{50}$ $41.2\;{\mu}g/ml$) and residual ($IC_{50}$ $47\;{\mu}g/ml$) fractions. The $IC_{50}$ value of allopurinol was $6.1\;{\mu}g/ml$. In addition, the hypouricemic and hepatic xanthine oxidase (XO)/xanthine dehydrogenase (XDH) inhibitory activities of the fractions were examined in vivo using oxonate (280 mg/kg, i.p.) induced hyperuricemic mice. At a dose of 200 mg/kg orally for 7 days, the pet-ether, chloroform and ethyl acetate fractions produced a significant (P < 0.01) reduction in serum urate level and also inhibited hepatic XO/XDH activities when compared to hyperuricemic mice. These inhibitory effects were weaker than that observed for the standard drug, allopurinol (10 mg/kg, p.o.). Lineweaver-Burk analysis of the enzyme kinetics indicated that the mode of inhibition was of a mixed type. These results suggest that the use of Coccinia grandis leaves for the treatment of gout could be attributed to its XO inhibitory activity.

• 생명과학회지
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• 제24권1호
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• pp.74-80
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• 2014

본 연구에서는 다양한 약효가 있다고 알려진 애기땅빈대(Euphorbia supina)의 추출물 및 분획물의 지방산 조성을 분석하고 인체 암세포 증식 억제효과에 대하여 살펴보았다. A+M과 MeOH 추출물의 지방산 조성 패턴은 유사했고 A+M과 MeOH 추출물은 각각 53.4% 및 42.1%의 18:3n-3를 함유하였다. 분획물들 중 85% aq. MeOH는 가장 높은 함량의 18:3n-3를 나타내었다. 애기땅빈대에 의한 암세포 증식 억제효과는 MeOH 추출물과 비교했을 때 A+M 추출물에 의한 억제효과가 높았으며 AGS 인체 위암세포에 대한 억제효과가 높았다. 분획물들 중에서는 n-Hexane과 85% aq. MeOH 분획물들에 의한 증식 억제효과가 높았다. 따라서 애기땅빈대의 항암 활성 성분은 n-Hexane과 85% aq. MeOH 분획물들에 함유되어 있는 것으로 여겨지며 향후 정제하여 규명할 필요가 있다고 사료된다.

• Ocean and Polar Research
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• 제41권2호
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• pp.79-88
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• 2019

In this study, the inhibitory effect of Atriplex gmelinii C. A. Mey. against the activity of MMP-2 and MMP-9 secreted from phorbol-12-myristate-13-acetate (PMA)-stimulated HT-1080 cells was evaluated by gelatin zymography and enzyme-linked immunosorbent assay (ELISA), reverse transcription polymerase-chain reaction (RT-PCR), and Western blot assay. Specimens of the halophyte A. gmelinii were extracted twice for 24 hr with methylene chloride ($CH_2Cl_2$), and then twice with methanol (MeOH), in turn. Each extract significantly inhibited the enzymatic activities in gelatin zymography and MMP ELISA kit, and expression of MMP-2 and 9 in mRNA and protein levels. Two crude extracts were combined and then the combined crude extracts were fractionated into n-hexane, 85% aqueous methanol (85% aq.MeOH), n-butanol (n-BuOH), and water ($H_2O$) fractions, according to solvent polarity. Among solvent-partitioned fractions, the 85% aq.MeOH fraction showed the strongest inhibitory effect against MMP-2 and -9 in gelatin zymography and MMP ELISA kit. In RT-PCR, all solvent-partitioned fractions significantly suppressed mRNA expression of MMP-2 and -9. On the other hand, in Western blot assay, all solvent-partitioned fractions except $H_2O$ significantly reduced expression levels of protein. HT 1080 cell migration was most significantly inhibited by the n-BuOH fraction followed by the 85% aq.MeOH and $H_2O$ fractions. These results suggest that A. gmelinii could be used as a potential source to inhibit tumor cell metastasis.

• 한국수산과학회지
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• 제41권3호
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• pp.176-181
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• 2008

To evaluate the effective use of endoprotease from squid viscera as a food processing aid, various methods of fractionating endoprotease from viscera of the Argentina shortfin squid (Illex argentinus) were evaluated. The endoprotease-positive fractions of each fractionation were fraction II (30-40%, w/w) with cold acetone, fraction IV (50-60% saturation) with ammonium sulfate, fraction UF with anion exchange chromatography, and fraction II (15-24 kDa) with gel filtration. The specific activities (approximately 25 U/mg) of the fractions using ammonium sulfate and gel filtration were higher than the others. Total azocaseinolytic activity and recovery of the positive fraction using gel filtration were 806.95U and 37.82%, respectively, and were the highest among the positive fractions. Based on the results, gel filtration was the most efficient method for fractionating endoprotease from the viscera of Illex argentinus.

• Preventive Nutrition and Food Science
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• 제11권1호
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• pp.6-9
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• 2006

This study was conducted to evaluate the antioxidant activity of each fraction from Sedum sarmentosum. Antioxidant activity of each fraction was measured using the DPPH radical assay, the ferric thiocyanate (FTC) method, and thiobarbituric acid (TBA) method. The antioxidant activities were then compared with that of BHT(synthetic antioxidant). The ethyl acetate and butanol fractions were found to have significant DPPH radical scavenging activity, with scavenging potencies showing 90.61 % and 87.02%, respectively. Total phenolic compound contents, determined according to the Folin-Denis method, were found to be in the order of ethyl acetate>butanol>ethanol>chloroform>aqueous fraction. From the results, we have been able to establish a positive correlation between the antioxidant activity and the total phenolic compound content of the sample. The antioxidant activity in a linoleic acid system was measured using the ferric thiocyanate (FTC) method and thiobarbituric acid (TBA) method. The ethyl acetate fraction had the highest antioxidant activity among the tested fractions. On the basis of these results, the ethyl acetate fraction provided equivalent or higher antioxidant activity as compared to BHT. These results suggest that Sedum sarmentosum is a potentially useful antioxidant for foods, cosmetics, and medicine.

• 한국지구과학회지
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• 제42권4호
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• pp.412-424
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• 2021

Understanding the distribution of heavy metals in sediment is necessary because labile heavy metals can partition into the water column and bioaccumulate in aquatic organisms. Here we investigated six heavy metals (Co, Cu, Mn, Ni, Pb, and Zn) in sediment cores using a five-step sequential leaching method to examine the occurrence of heavy metals in the sediment. The results showed that all elements, except Mn, are depleted in the exchangeable and carbonate fractions. However, heavy metal concentrations are much higher in the Fe-Mn oxide and organic matter fractions, especially for Cu, indicating enrichment in the organic matter fraction. Furthermore, contamination parameters (contamination factor and geoaccumulation index) indicate that Mn contamination is high, primarily derived from anthropogenic sources, presenting a potential risk to ecosystems in the Nakdong River.

• 생약학회지
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• 제24권4호
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• pp.289-295
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• 1993

Polysaccharides fractions from the leaves of Artemisia selengensis$(ASP_1)$ and Artemisia iwayomogi$(ASP_1)$ were extracted and purified by Sephadex gel filtration and DEAE-Sephadex ion exchange chromatographies. Both $ASP_1$ and $AIP_1$ fractions were tested for their effects on the spleen cell culture in vitro. Both $ASP_1$ and $AIP_1$ fractions allow growth of spleen cells up to 3 months in culture, suggesting the immunoregulatory activities of those polysaccharide fractions. The molecular weights of $ASP_1$ and $ASI_1$ fractions were found to be about 2,500 daltons by Sephadex gel filtration chromatography using standard dextrans. Both $ASP_1$ and $AIP_1$ fractions were composed of glucose, xylose and galactose.