• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 하계학술대회 논문집 Vol.5 No.1
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• pp.527-530
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• 2004

High-temperature Superconductor(HTS) tubes were fabricated in term of different diameter, length and thickness by centrigugal forming method. For powder melting by induction the optimum range of melting temperatures and preheating temperature were $1050^{\circ}C{\sim}1100^{\circ}C\;amd\;550^{\circ}C$ for 30min, respectively. The mould renting speed was 1000rpm. A tube was annealed at $840^{\circ}C$ for 72hours in oxygen atmosphere. The plate-like grains were well developed along the renting direction and typical grain size was about more than $40{\mu}m$. It was found that Ic values increased with increasing the tube diameter while the Ic decreased with increasing tube thickness. Also Ic decreased with increasing the tube length. The measured Ic in $50mm{\times}70mm{\times}25mm$ tube was about 896Amp.

• 한국식품과학회지
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• 제39권6호
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• pp.669-675
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• 2007

본 연구자들은 Cumin(Cuminum cymium L.) seed로부터 정제한 $2-hydroxyethyl-{\beta}-undecenate$의 항치주염 활성을 사람의 백혈구를 이용하여 염증 매개물질 $LTB_4$ 및 PGs의 생성 효소인 5-lipoxygenase와 cyclooxygenase, 및 조직파괴 효소인 collagenase와 elastase의 저해 효과를 규명하여 다음과 같은 결론을 얻었다. HPS의 항치주염 활성을 사람의 백혈구를 이용하여 염증 매개물질 $LTB_4$ 및 PGs의 생성 효소인 5-lipoxygenase와 cyclooxygenase 및 조직파괴효소인 collagenase와 elastase의 저해효과를 규명한 결과, HPS은 $5\;{\times}\;10^{-2}\;M$ 첨가 시 97%의 PMNL로부터 $LTB_4$ 생합성이 저해되었으며 이때 $IC_{50}$ 값은 $2\;{\times}\;10^{-4}\;M$ 이었다. 균질화된 사람의 PMNL 5-lipoxygenase 및 시판 정제 5-lipoxygenase 활성에 대한 HPS의 저해 효과는 $5\;{\times}\;10^{-2}\;M$첨가 시 92%의 효소 활성이 저해되었다. 또한 효소 활성에 대한 $IC_{50}$ 값은 $2.5\;{\times}\;10^{-4}\;M$이었으며, 정제 5-lipoxygenase에 대한 $IC_{50}$ 값은 $2.3\;{\times}\;10^{-4}\;M$이었다. 또한 백혈구 COX 활성에 대한 $IC_{50}$ 값은 $5.1\;{\times}\;10^{-4}\;M$이었고, 정제 COX에 대한 $IC_{50}$ 값은 $2.3\;{\times}\;10^{-4}\;M$이었으며, 백혈구 collagenase 활성에 대한 $IC_{50}$ 값은 $2\;{\times}\;10^{-3}\;M$이었고 정제 collagenase에 대한 $IC_{50}$ 값은 $5\;{\times}\;10^{-2}\;M$이었다. 백혈구 elastase의 경우 $5\;{\times}\;10^{-2}\;M$ 첨가 시 66%의 활성이 저해된 반면 정제 elastase의 경우 $5\;{\times}\;10^{-2}\;M$ 첨가 시 25%의 효소 활성이 저해되었다. 또한 백혈구 elastase 활성에 대한 $IC_{50}$ 값은 $7.5\;{\times}\;10^{-3}\;M$이었다. 인체 치은세포에 대한 독성 시험 결과 $5\;{\times}\;10^{-2}\;M$의 HPS 첨가시 세포의 활성은 배양 2일째 47.83%로 나타났으며, $1\;{\times}\;10^{-2}\;M$의 HPS 첨가시에도 68.53%로 나타나 비교적 세포독성이 강한 것으로 나타났다.

• 대한화장품학회지
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• 제35권3호
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• pp.243-250
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• 2009

천연 미백 소재 개발을 위하여 복령피 추출물과 복령피 추출물에서 분리한 활성 물질의 멜라닌 생성에 연관된 생리 활성을 분석하였다. 복령피 추출물은 $100{\mu}g$/mL 이하에서 세포 독성이 없는 것으로 확인 되었으며 free radical 소거능(DPPH)과 superoxide radicals 소거능 결과는 각각 $IC_{50}=19.4{\pm}2.21{\mu}g$/mL, $IC_{50}=103{\pm}3.33{\mu}g$/mL을 나타내었다. $50{\mu}g$/mL 농도에서 B16 melanoma 세포 내 tyrosinase의 활성을 34 % 저해 하였으며, 세포 내 멜라닌 생합성 저해 효과는 $50{\mu}g$/mL 농도의 복령피 추출물을 72 h 동안 처리한 세포에서 51 % 억제율을 보이는 것으로 나타났다. 이러한 복령피 추출물의 활성 물질을 분리하여 $^1H$-NMR, $^{13}C$-NMR, Mass analysis 등의 기기 분석을 실시한 결과 triterpene류의 3-$\beta$-hydroxylanosta-7,9(11),24-trien-4-oic acid로 동정되었고 $100{\mu}g$/mL 이하에서 세포 독성이 없는 것으로 확인 되었다. 3-$\beta$-hydroxylanosta-7,9(11),24-trien-4-oic acid의 free radical 소거능과 superoxide radicals 소거능 결과는 각각 $IC_{50}=4.3{\pm}0.15{\mu}g$/mL, $IC_{50}=54{\pm}1.67{\mu}g$/mL을 나타내었다. $10{\mu}g$/mL 농도에서 세포내 tyrosinase의 활성을 43 % 저해 하였으며, 멜라닌 저해 효과를 확인한 결과 $IC_{50}=3.6{\mu}g$/mL으로 나타났다. Western blot을 이용하여 tyrosinase, tyrosinase related protein-1 (TRP-1), TRP-2 단백질의 발현 감소를 확인하였다. 복령피 추출물과 3-$\beta$-hydroxylanosta-7,9(11),24-trien-4-oic acid는 우수한 미백 효능을 갖는 화장품 소재로의 개발 가능성이 클 것으로 기대된다.

• Food Science and Biotechnology
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• 제17권2호
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• pp.279-286
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• 2008

The antioxidative activity of various enzymatic extracts from leaves of Perilla frutescens var. japonica was evaluated by measuring 1,1-diphenyl-2-picrylhydrazyl (DPPH), hydroxyl, and alkyl radical scavenging activity using an electron spin resonance (ESR) spectrometer. For this study, the leaves were enzymatically hydrolyzed by 8 carbohydrases (Dextrozyme, AMG, Promozyme, Maltogenase, Termamyl, Viscozyme, Celluclast, and BAN) and 9 proteases [Flavourzyme, Neutrase, Protamex, Alcalase, PP-trypsin (trypsin from porcine pancreas), papain, pepsin, $\alpha$-chymotrypsin, and BP-trypsin (trypsin from bovine pancreas)]. The DPPH radical scavenging activities of Promozyme and Alcalase extracts were the highest, and the $IC_{50}$ values were 77.25 and $109.66\;{\mu}g/mL$, respectively. All enzymatic extracts of the leaves scavenged hydroxyl radical, and the $IC_{50}$ values of Celluclast and pepsin extracts which were the highest activity were 243.34 and $241.86\;{\mu}g/mL$, respectively. The BAN and $\alpha$-chymotrypsin extracts showed the highest scavenging activities, and the $IC_{50}$ values were 21.13 and $33.23\;{\mu}g/mL$, respectively. The pepsin extracts from the leaves showed protective effect on $H_2O_2$-induced DNA damage. In addition, the pepsin extracts decreased cell death in PC-12 cells against $H_2O_2$-induced oxidative damage. The findings of the present study suggest that enzymatic extracts of the leaves possess antioxidative activity.

• 한국약용작물학회지
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• 제14권5호
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• pp.267-272
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• 2006

Phytochemical study on the EtOAc fraction from the MeOH extract of the leaves of Cedrela sinensis led to the isolation of five known phenolic compounds (1-5), whose structures were identified as (+)-catechin (1), $kaempferol-3-0-{\alpha}- L-rhamnopyranoside$ (2), quercetin (3), $quercetin-3-O-{\alpha}-L-rhamnopyranoside$ (4), and $quercetin-3-O-{\beta}-D-glucopyranoside$ (5), respectively, by comparing their spectral $(uv,\;JR,\;IH\;and\;^{13}C-NMR,\;and\;ESI-MS)$ and physicochemical data with those reported in the literature. Among the isolated compounds (1-5), compounds 1 and 3-5 exhibited significant DPPH radical scavenging effects with $IC{_50}$ values ranging from $21.3{\pm}1.4\;to\;38.1{\pm}3.2 {\mu}M$ as well as superoxide anion radical scavenging effects with $IC{_50}$ values ranging from $9.4{\pm}0.7\;to\;21.2{\pm}3.6 {\mu}M$. Furthermore, compounds 1 and 3-5 also exhibited considerable inhibitory effects on LDL peroxidation induced by either $CU^{2+}$ or AAPH with $IC{_50}$ values ranging from $1.4{\pm}0.4\;to\;11.9{\pm}1.4\;{\mu}M$. These results indicated that flavonoids are the major constituents of C. sinensis and considered to be antioxidant principles of this plant.

• Journal of Microbiology and Biotechnology
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• 제30권6호
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• pp.893-902
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• 2020

Propolis is a resinous substance that is collected by Apis mellifera from plant sources and is used in traditional medicine. To study the phytochemical constituents and apoptotic potential of Jordanian propolis extract against different cancer cell lines, propolis was extracted using methanol, hexane, and ethyl acetate and was fractionated using chromatographic methods. Cytotoxicity was assessed using MTT and LDH assays. The apoptotic potential was investigated using florescence microscopy, multicaspase assay, Annexin-V and dead cell assay, and cell cycle assay. The phytochemical constituents were analyzed using GC-MS. The methanol extract of propolis exhibited cytotoxic potential against all cell lines tested. The IC₅₀ values of the methanol extract were 47.4, 77.8, 91.2, and 145.0 ㎍/ml for HepG2, LoVo, MDAMB231, and MCF7 cell lines, respectively. The IC₅₀ values of the F1 fraction were 31.6 (MDAMB231), 38.9 (HepG2), 36.7 (LoVo) and 75.5 (MCF7) ㎍/ml. On further purification using thin-layer chromatography, the IC₅₀ values of the F1-3 fraction were found to be 84.31(HepG2), 79.2 (MCF7), 70.4 (LoVo), and 68.9 (MDAMB231) ㎍/ml, respectively. The anticancer potential of the F1 fraction was confirmed through the induction of apoptosis and cell cycle arrest at the G0/G1 phase. The GC-MS analysis of the F1 fraction revealed the presence of 3-methyl-4-isopropylphenol (29.44%) as a major constituent. These findings indicate the potential of propolis extract as a cancer therapy. However, further investigation is required to assess the acute and subacute toxicity of the most active fraction.

• Archives of Pharmacal Research
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• 제28권1호
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• pp.22-27
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• 2005

Bioassay-guided fractionation of methanol extract of Reynoutria sachalinensis flower using DPPH assay has led to the isolation of three anthraquinones and three flavonoids. Their structures were identified as emodin (1), emodin-8-O-$\beta$-D-glucopyranoside (2), physcion-8-O-$\beta$-D­glucopyranoside (3), quercetin-3-O-$\alpha$-L-arabinofuranoside (4), quercetin-3-O-$\beta$-D-galactopyra­noside (5), and quercetin-3-O-$\beta$-D-glucuronopyranoside (6) by comparing their physicochemical and spectral data with those published in literatures. All isolated compounds were evaluated for antioxidant activities with free radical 1, 1-diphenyl-2-picrylhydrazyl (DPPH) scavenging, superoxide radical scavenging and $Cu^{2+}$-mediated low density lipoprotein (LDL) oxidation assay. The results demonstrated that three flavonoids, 4, 5, and 6 had remarkable antioxidant activities with the $IC_{50}$ values of 64.3, 54.7, and 46.2${\mu}M$ (DPPH scavenging), the $IC_{50}$ values of 6.0, 6.7, and $4.4{\mu}M$ (superoxide radical scavenging) and the $IC_{50}$ values of 3.8, 3.2, and 5.4${\mu}M$ against LDL oxidation, respectively.

• Asian Pacific Journal of Cancer Prevention
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• 제17권4호
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• pp.2277-2284
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• 2016

Ribosome-inactivating protein (RIP) from Mirabilis jalapa L. leaves has cytotoxic effects on breast cancer cell lines but is less toxic towards normal cells. However, it can easily be degraded after administration so it needs to be formulated into nanoparticles to increase its resistance to enzymatic degradation. The objectives of this study were to develop a protein extract of M. jalapa L. leaves (RIP-MJ) incorporated into nanoparticles conjugated with Anti-EpCAM antibodies, and to determine its cytotoxicity and selectivity in the T47D breast cancer cell line. RIP-MJ was extracted from red-flowered M. jalapa L. leaves. Nanoparticles were formulated based on polyelectrolyte complexation using low viscosity chitosan and alginate, then chemically conjugated with anti-EpCAM antibody using EDAC based on carbodiimide reaction. RIP-MJ nanoparticles were characterised for the particle size, polydispersity index, zeta potential, particle morphology, and entrapment efficiency. The cytotoxicity of RIP-MJ nanoparticles against T47D and Vero cells was then determined with MTT assay. The optimal formula of RIP-MJ nanoparticles was obtained at the concentration of RIP-MJ, low viscosity chitosan and alginate respectively 0.05%, 1%, and 0.4% (m/v). RIP-MJ nanoparticles are hexagonal with high entrapment efficiency of 98.6%, average size of 130.7 nm, polydispersity index of 0.380 and zeta potential +26.33 mV. The $IC_{50}$ values of both anti-EpCAM-conjugated and non-conjugated RIP-MJ nanoparticles for T47D cells (13.3 and $14.9{\mu}g/mL$) were lower than for Vero cells (27.8 and $33.6{\mu}g/mL$). The $IC_{50}$ values of conjugated and non-conjugated RIP-MJ for both cells were much lower than $IC_{50}$ values of non-formulated RIP-MJ (>$500{\mu}g/mL$).

• 약학회지
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• 제59권2호
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• pp.49-54
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• 2015

In the present study we evaluated comparative herb-drug interaction potential of red ginseng total powder, ginsenoside Rg1, and Rb1 by inhibition of CYP isoforms including CYP1A2, CYP2A6, CYP2B6, CYP2C9, CYP2C19, CYP2D6, CYP2E1 and CYP3A4 using pooled human liver microsomes (HLMs). As measured by liquid chromatography-electrospray ionization tandem mass spectrometry, red ginseng total powder inhibited significantly activities of CYP1A2, CYP2A6, CYP2B6, CYP2C9, CYP2C19, CYP2D6, CYP2E1 and testosterone 6-beta hydroxylation by CYP3A4, but the $IC_{50}$ values were higher than $556{\mu}g/ml$. Activities of CYP2B6, CYP2C9, CYP2D6 and CYP3A4 were inhibited by ginsenoside Rb1. Also, activities of CYP1A2, CYP2A6, CYP2B6, CYP2C9, CYP2C19, CYP2D6 and testosterone 6-beta hydroxylation by CYP3A4 were inhibited by ginsenoside Rg1. The $IC_{50}$ values of ginsenoside Rb1 and Rg1 were higher than $200{\mu}g/ml$. Based on $IC_{50}$ values against CYP isoforms, ginsenosides-drug interactions by CYP inhibition may be very low in clinical situations.

• Archives of Pharmacal Research
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• 제18권2호
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• pp.105-112
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• 1995

In ordedr to gain insight into the mechanisms byl which erythropoietin promotes erythropoiesis, effects of various inhibitors on the erythropoietin-propmoted differentiation of erythroid progenitor cells and on the erythroid progenitor cells and on the erythropoietin-promoted $Ca^{++}$ uptake in the progenitor cells were determined, and the relationship between the inhibitory activity of each inhibitor cells were determined, and he relationship between the inhibitory activity of each inhibitor toward the differentiation and channel blocker (varapamil), a $Ca^{++}$ chelator (EDTA) and a protein kinase C inhibitor (stauroporine). All of these agents inhibited both the erythropoietin-mediated differentiation of the erythroid progenitor cells, as determined by the incroporation of $^{59}Fe$ into heme, and $Ca^{++}$ uptake in a concentrtion dependent manner. In the cases of varapamil and EDTA, the half-miximal inhibitory concentration $(IC_{50})$ values for differentiation of the progenitor cells may be theconsequence of the inhibition of the $Ca^{++}$ uptake in a concentration dependent manner. In the cases of varapamil and EDTA, the half-miximal inhibitory concentration dependent manner. In the cases of verapamil and EDTA, the half-miximal inhibitory concentration $(IC_{50})$ values for differentiation of the progenitor cells may be the consequence of the inhibition of the $Ca^{++}$ uptake by the inhibitor. On the other hand, in the cases of genistein and stauroporine, the $IC_{50}$ values for inhibition of differentitation were significantly different from that for inhibition of $Ca^{++}$uptake. These results suggest that the mechanism of inhibition of differentiation by these two inhibitors in complex. However, taken all together, the above results support the proposition that $Ca^{++}$ uptake may play a role in the erythropoietin-mediated differentiation of erythoid progenitor cells.