• 한국응용과학기술학회지
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• 제6권1호
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• pp.51-57
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• 1989

A series of four sodium ${\alpha}-sulfo$ fatty vinyl ester oligomers including sodium ${\alpha}-sulfo$ lauric acid vinyl ester oligomer, sodium ${\alpha}-sulfo$ myristic acid vinyl ester oligomer, sodium ${\alpha}-sulfo$ palmitic acid vinyl ester oligomer and sodium ${\alpha}-sulfo$ stearic acid vinyl ester oligomer were examined for surface activities such as surface tension, foaming power, foam stability, emulsifying power, dispersion effect, solubilization of orange OT. The critical micelle concentration(CMC) was also evaluated. Consequently, these sodium ${\alpha}-sulfo$ fatty acid vinyl ester oligomers were shown to have a good cohesive power and dispersion effect.

• JSTS:Journal of Semiconductor Technology and Science
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• 제14권1호
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• pp.92-95
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• 2014

In this work we have synthesized ZnS:Mn nanocrystals (NCs) using a simple one step thermochemical method. $Zn(NO_3)_2$ and $Na_2S_2O_3$ were used as the precursors and $Mn(NO_3)_2$ was the source of impurity. Thioglycolic acid (TGA) was used as the capping agent and the catalyst of the reaction. The structure and optical property of the NCs were characterized by means of X- ray diffraction (XRD), HRTEM, UV-visible optical spectroscopy and photoluminescence (PL). X-ray diffraction (XRD) and transmission electron microscopy (TEM) analyses demonstrated cubic phase ZnS:Mn NCs with an average size around 3 nm. Synthesized NCs exhibited band gap of about 4 eV. Photoluminescence spectra showed a yellow-orange emission with a peak located at 585 nm, demonstrating the Mn incorporation inside the ZnS particles.

• 영미문화
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• 제18권4호
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• pp.1-31
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• 2018

It is needless to say that America's indiscriminate artillery and chemical attacks have worsened the conditions of Vietnam's tropical rain forests, causing war-torn combat troops and civilians to suffer more from the participation and aftermath of the Vietnam war. Around two decades after the Vietnam War, American and Vietnamese writers dealing with the destruction of the human and nature of the Vietnam War and the following traumatic experience commonly report the horrors of inhumane warfare, but some differences among them appear in the reception of the ecocide consciousness. For American writers who had been involuntarily involved or who had stayed in the back area as interpreters and counter-intelligence force, the Vietnam War was often a kind of exotic "addicted adventure" which their American hometown could not provide. But apart from overcoming postwar post-traumatic stress by writing of healing which was shared with American war writers, Vietnamese writers have been able to overcome the scars of war as the communal memorial, which Jonathan Shay emphasized as the necessary comforting ritual by community members showing the sign of honor and care. On the other hand, American war writers were on the side of "separate peace," as Jeong stressed, and the Vietnam War to them was more racist like the case of "body count." Nevertheless, it is fortunate that the hideous experience of war could turn them all into the creativity pool, just as the 5,000 square mile of bomb creators have been used as the postwar fish ponds.

• 한국식품과학회지
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• 제45권5호
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• pp.598-604
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• 2013

본 연구는 citrus 과피의 천연 갈변저해제로서 사용가능성을 알아보았다. Citrus 중 생과 및 가공에서 가장 많이 이용되고 있는 오렌지(C. sinensis), 감귤(C. unshiu), 레몬(C. limon), 자몽(C. paradisi)의 과피를 80% 에탄올로 추출 농축하였다. 각 추출물 0.05-5%에 사과 슬라이스를 침지하여 외관 및 색도 변화를 관찰한 후, pH와 페놀 및 플라보노이드 함량을 조사하였으며, DPPH radical 소거 활성과 $Cu^{2+}$ 킬레이트 활성을 측정하였다. 사과 슬라이스 침지의 경우 다양한 농도의 추출물 중 대체로 0.1%에서 우수한 갈변저해효과를 보였으며 4종의 citrus 과피 중 레몬 과피추출물이 가장 우수한 효과를 보였다. pH의 경우 4종의 citrus 과피 추출물 간의 유의적 차이는 없었으며, ascorbic acid에 비해 높은 값을 보였고, 총 페놀 및 플라보노이드 함량의 경우 레몬 과피 추출물이 가장 높게 측정되었다. DPPH radical 소거활성과 $Cu^{2+}$ 킬레이트 활성 모두 레몬 과피 추출물이 가장 우수하였고, 자몽 과피 추출물이 가장 낮은 활성을 보였다. 사과 슬라이스 침지 결과와 radical 소거 및 킬레이트 활성이 페놀 및 플라보노이드와 유사한 경향을 보이고 있어 이 물질들이 항산화 및 갈변저해 효과를 나타낸다고 추정된다. Citrus 과피 추출물의 항산화능은 농도 의존적이었지만 갈변저해효과는 mono 및 diphenol 과 같은 기질로 작용하는 페놀성 물질의 일부와 추출물 자체가 띠는 색으로 인해 0.1-0.5%에서 효과적이었다. 따라서 본 연구를 통해 citrus 과피 특히, 레몬 과피 추출물의 항산화와 갈변저해효과를 확인하였고, 천연 갈변저해제로서의 사용 가능성을 제시하였다.

• Weed & Turfgrass Science
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• 제3권4호
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• pp.378-381
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• 2014

Zoysiagrass는 대표적인 난지형 잔디로 Curvularia leaf spot, Large patch, Rhizoctonia blight, Spring dead spot, 그리고 Dollar spot 등의 다양한 병에 직면해 있으며 최근에는 많은 병원균들의 복합 감염에 의한 잔디병 양상을 보이고 있다. 최근에 패취형태의 병반을 가진 zoysiagrass 엽조직으로 부터 Rhizoctonia 속과 유사한 곰팡이를 분리하였다. 리보소옴 DNA의 염기서열을 분석하여 Waitea circinata 균주들과 98% 이상의 상동성을 보였고, Koch's 법칙에 따라 zoysiagrass에서 병원성을 확인하여 이 병의 주 원인균은 Waitea circinata로 판명되었다. 따라서 본 병은 zoysiagrass에서 Waitea circinata에 의해 최초로 국내에서 발생한 병으로 사료되며, 기본 병명과 동일하게 Waitea ring patch로 사용하기를 제안하고자 한다.

• 한국환경성돌연변이발암원학회지
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• 제21권1호
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• pp.51-56
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• 2001

Kimchi is a major Korean traditional fermented food, as a supplying source of vitamin and minerals which is prepared with various vegetables and condiments such as red pepper, garlic and salted fish etc. There are many types of Kimchi depending on the ingredients and preparation methods used. To investigate the clastogenicity and anticlastogenicity of Baechu (Chinese cabbage) Kimchi and Buchu (leek, Allium odorum) Kimchi in mouse, it was performed acridine orange supravital staining of micronucleus (AOSS-MN) assay using mouse peripheral reticulocytes. Baechu Kimchi and Buchu Kimchi were cultivated by organic agricultural technique, and Kimchi samples were prepared by methanol extraction and lyophilization. First of all, it was studied the clastogenicity of two Kimchi samples themselves (250-1,000 mg/kg) after oral adminstration in mouse. And also to study the anticlastogenic effect of oral administration of Kimchi samples, mitomycin C (MMC, 1 mg/kg, i.p.) was used as micronucleus inducing agent in this study. Dosing scheme was performed as simultaneous (co-treatment), 3 hr before (pre-treatment) and 3 hr after (post-treatment) with MMC treatment. Two Kimchi samples in the range of 250-1,000 mg/kg did not reveal any clastogenic effect in AOSS-MN assay in mouse. They also revealed anticlastogenic effects in post-treatment of Baechu Kimchi (1,000 mg/kg), and in pre-treatment of Buchu Kimchi (500 and 1,000 mg/kg) with statistical significance. The anticlastogenic effect revealed 1 and 6 hr after treatment of Baechu Kimchi, and Buchu Kimchi with 3 and 6 hr pretreatment. Consequently, it is suggested that antimutagenic and anticlastogenic mechanisms of Baechu and Buchu Kimchi in vivo attributed to sipindle formation and kinetic behavior of mutagens such as absorption and metabolism etc.

• 한국미생물·생명공학회지
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• 제46권1호
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• pp.40-44
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• 2018

Gram 양성세균의 생육을 억제하는 세균을 청주시 무심천 토양에서 분리하였으며, 16S rRNA 유전자 염기서열 분석 결과 Pseudomonas otitidis PS로 동정하였다. PS 균주는 0.5%의 glucose가 포함된 1% soybean meal 배지에서 2차 대사 산물로서 최대 약 0.1%의 수율로 항생물질을 생산하였다. 항생물질 성분은 ethyl acetate로 추출하였으며, Staphylococcus aureus KCTC 1261에 대한 minimum inhibitory concentration은 $2{\mu}g/ml$이었다. 이 성분은 siderophore 활성을 띠어서 chrome azurol S 평판배지에서 주황색 halo를 나타내었으며, 철이 제거되면 생육 억제 효과는 감소하였다. Ascorbic acid 같은 환원제를 첨가하거나 혐기적 환경에서는 항생물질 활성을 잃으므로 PS 항생물질은 활성산소를 방출하여 bactericidal activity를 갖는 것으로 보인다.

• Asian Pacific Journal of Cancer Prevention
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• 제16권17호
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• pp.7943-7957
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• 2015

Background and Aims: Colorectal cancer is one of the leading causes of death in the world. The aim of this study was to investigate the growth-suppression potentiality of a crude saponin extract (CSENS) prepared from medicinal herb, Nigella sativa, on human colon cancer cells, HCT116. Materials and Methods: HCT116 cells were subjected to increasing doses of CSENS for 24, 48 and 72 h, and then harvested and assayed for cell viability by WST-1. Flow cytometry analyses, cell death detection ELISA, fluorescent stains (Hoechst 33342 and acridine orange/ethidium bromide), DNA laddering and comet assays were carried out to confirm the apoptogenic effects of CSENS. Luciferase reporter gene assays, quantitative reverse transcription-polymerase chain reaction and Western blot analyses were performed to assess the impact of CAERS and CFEZO on the expression levels of key regulatory proteins in HCT116 cells. Results: The results demonstrated that CSENS inhibited proliferation and induced apoptosis. Apoptosis was confirmed by flow cytometry analyses, while CSENS-treated cells exhibited morphological hallmarks of apoptosis including cell shrinkage, irregularity in cellular shape, cellular detachment and chromatin condensation. Biochemical signs of apoptosis, such as DNA degradation, were observed by comet assay and gel electrophoresis. The pro-apoptotic effect of CSENS was caspase-3-independent and associated with increase of the Bax/Bcl-2 ratio. CSENS treatment down-regulated transcriptional and DNA-binding activities of NF-${\kappa}B$ and AP-1 proteins, associated with down-regulation of their target oncogenes, c-Myc, cyclin D1 and survivin. On the other hand, CSENS up-regulated transcriptional and DNA-binding activities of Nrf2 and expression of cytoprotective genes. In addition, CSENS modulated the expression levels of ERK1/2 MAPK, p53 and p21. Conclusions: These findings suggest that CSENS may be a valuable agent for treatment of colon cancer.

• Asian Pacific Journal of Cancer Prevention
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• 제15권17호
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• pp.7473-7478
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• 2014

Cholangiocarcinoma (CCA) is a fatal cancer with poor prognosis and less than 10% of CCA patients can be offered surgical cure. Conventional chemotherapy results in unfavorable outcomes. At present, plant-derived compounds are gaining interest as potential cancer therapeutics, particularly for treatment-refractory cancers. In this study, antitumor activity of tiliacorinine, the major alkaloid isolated from a tropical plant, on CCA was first demonstrated. Antiproliferative effects of tiliacorinine on human CCA cell lines were investigated using SRB assays. Acridine orange/ethidium bromide staining, flow cytometric analysis and DNA laddering assays were used for apoptotic determination. Apoptosis-related proteins were verified by Western blotting and antitumor activity of tiliacorinine in vivo was demonstrated in CCA xenografted mice. Tiliacorinine significantly inhibited proliferation of human CCA cell lines with $IC_{50}$ $4.5-7{\mu}M$ by inducing apoptosis through caspase activation, upregulation of BAX, and downregulation of $Bcl_{xL}$ and XIAP. Tiliacorinine considerably reduced tumor growth in CCA xenografted mice. These results demonstrated antitumor effects of tiliacorinine on human CCA in vitro and in vivo. Tiliacorinine may be an effective agent for CCA treatment.

• BMB Reports
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• 제38권4호
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• pp.391-398
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• 2005

3-hydrogenwadaphnin (3-HK) is a new daphnane-type diterpene ester isolated from Dendrostellera lessertii with strong anti-tumoral activity in animal models and in cultures. Here, prolonged effects of this new agent on proliferation and viability of several different cancerous cell lines were evaluated. Using [$^3H$]thymidine incorporation, it was found that the drug inhibited cell proliferation and induced G1/S cell cycle arrest in leukemic cells 24 h after a single dose treatment. The cell viability of Jurkat cells was also decreased by almost 10%, 31% and 40% after a single dose treatment (7.5 nM) at 24, 48 and 72 h, respectively. The drug-treated cells were stained with acridine orange/ethidium bromide to document the chromatin condensation and DNA fragmentation. These observations were further confirmed by detection of DNA laddering pattern in the agarose gel electrophoresis of the extracted DNA from the treated cells. Treatment of K562 cells with the drug at 7.5, 15 and 30 nM caused apoptosis in 25%, 45% and 65% of the cells, respectively. Exogenous addition of $25-50\;{\mu}M$ guanosine and/or deoxyguanosine to the cell culture of the drug-treated cells restored DNA synthesis, released cell arrest at G1/S checkpoint and decreased the apoptotic cell death caused by the drug. These observations were not made using adenosine. However, the drug effects on K562 cells were potentiated by hypoxanthine. Based on these observations, perturbation of GTP metabolism is considered as one of the main reasons for apoptotic cell death by 3-HK.