• Title/Summary/Keyword: Srb

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A Study of Thermal Radiation from The Alumina Particle Cloud in The Plume Using View Factor Method (형상 계수를 이용한 알루미나 입자구름의 열복사 예측 기법 연구)

  • Ko, Ju-Yong;Kim, In-Sun
    • Proceedings of the KSME Conference
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    • 2007.05b
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    • pp.2044-2049
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    • 2007
  • In order to predict the thermal radiation induced from alumina particle cloud in the plume of solid propellant motor, view factor method is applied to space shuttle SRB and the result is compared with that of monte carlo method. For this purpose, radiative characteristics, such as particle cloud temperature distribution, effective emissivity or emissive power of particle cloud are studied. In the case of effective emissivity, inverse wavelength method is applied and plume reduction characteristic length is used for emissive power distribution. As a result, thermal radiation using view factor method gives more conservative results than that using monte carlo method. So it can be used for preliminary design of thermal protection system.

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Cytotoxic Sesquiterpenoid from the Seeds of Amomum xanthioides

  • Kim, Ki-Hyun;Choi, Jung-Wook;Choi, Sang-Un;Lee, Kang-Ro
    • Natural Product Sciences
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    • v.17 no.1
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    • pp.10-13
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    • 2011
  • As parts of our continuing search for biologically active compounds from medicinal plants, we investigated the constituents of the seeds of Amomum xanthioides and isolated a sesquiterpenoid, a nerolidol derivative from its MeOH extract. The chemical structure was determined by spectroscopic methods, including 1D and 2D NMR to be ($2S^*$,$2'R^*$,$5'S^*$)-2-(5'-ethenyltetrahydro-5'-methylfuran-2'-yl)-6-methylhept-5en-2-ol (1). Compound 1 was isolated for the first time from nature source. Compound 1 exhibited a good cytotoxicity against SK-OV-3 and SK-MEL-2 cells ($IC_{50}$: 16.7 and $8.6\;{\mu}M$, respectively) using a SRB bioassay. In this study, we also determined the absolute configuration of 2 reported in previous paper.

Phenolic Constituents of Althaea rosea Canival. (접시꽃뿌리의 페놀성 성분)

  • Kim, Do-Hoon;Yang, Min-Cheol;Lee, Kyu-Ha;Kim, Ki-Hyun;Lee, Kang-Ro
    • Korean Journal of Pharmacognosy
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    • v.38 no.3 s.150
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    • pp.222-226
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    • 2007
  • Seven compounds, scopoletin (1), p-hydroxyphenethyl trans-ferulate (2), $1-({\alpha}-L-rhamnosyl(1\;{\rightarrow}\;6)-{\beta}-D-glucopyranosyloxy)-3,4,5-trimethoxybenzene$ (3), benzyl ${\alpha}-L-rhamnopyranosyl(1\;{\rightarrow}\;6)-{\beta}-D-glucopyranoside$ (4), suberic acid (5), sebacic acid (6) and scopolin (7) were isolated from the methanol extract of the roots of Althaea rosea Canival. Compounds $1\;{\sim}\;7$ were first isolated from this plant. The isolated compounds were tested for their cytotoxicity against human cancer cell lines using a SRB method in vitro.

Phytochemical Constituents of Geranium eriostemon

  • Chang, Sang-Wook;Kim, Ki-Hyun;Lee, Il-Kyun;Choi, Sang-Un;Lee, Kang-Ro
    • Natural Product Sciences
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    • v.15 no.3
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    • pp.151-155
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    • 2009
  • Phytochemical investigation of the MeOH extract of the aerial parts of Geranium eriostemon resulted in the isolation of one triterpene, three furofuran lignans, one syringic acid and four flavonoids. Their chemical structures were characterized by spectroscopic methods to be oleanolic acid (1), (-)-kobusin (2), (-)-eudesmin (3), (+)-magnolin (4), syringic acid (5), quercetin (6), juglanin (7), juglalin (8), and hyperin (9). All compounds (1 - 9) were isolated for the first time from this plant source and the compounds 2 - 4 were reported first from the genus Geranium. Compounds 4 - 6 exhibited moderate cytotoxicity against four human cancer cell lines in vitro using a SRB bioassay.

Phytochemical Constituents of Thesium chinense TURCZ and Their Cytotoxic Activities In Vitro

  • Lee, Il-Kyun;Kim, Ki-Hyun;Choi, Sang-Un;Lee, Jae-Hyun;Lee, Kang-Ro
    • Natural Product Sciences
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    • v.15 no.4
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    • pp.246-249
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    • 2009
  • Column chromatographic separation of the MeOH extract from the aerial parts of Thesium chinense TURCZ led to the isolation of two norsesquiterpenes (1 - 2), two phenylpropanes (3 - 4) and four flavonoids (5 - 8). Their structures were determined by spectroscopic means to be 5,6-epoxy-3-hydroxy-7-megastigmen-9-ene (1), (-)-loliolide (2), methyl-p-hydroxycinnamate (3), methyl caffeate (4), kaempferol (5), kaempferol-3-O-${\beta}$-Dglucopyranoside (6), kaepmferol-3,7-di-O-${\beta}$-D-glucopyranoside (7) and kaempferol-3-O-${\beta}$-D-glucopyranoside-6''-(3-hydroxy-3-methylglutarate) (8). Compounds 1 - 4, 7 and 8 were first isolated from this source. The isolated compounds were evaluated for their cytotoxicty in vitro using the sulforhodamin B bioassay (SRB).

Effects of Iron-Reducing Bacteria on Carbon Steel Corrosion Induced by Thermophilic Sulfate-Reducing Consortia

  • Valencia-Cantero, Eduardo;Pena-Cabriales, Juan Jose
    • Journal of Microbiology and Biotechnology
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    • v.24 no.2
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    • pp.280-286
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    • 2014
  • Four thermophilic bacterial species, including the iron-reducing bacterium Geobacillus sp. G2 and the sulfate-reducing bacterium Desulfotomaculum sp. SRB-M, were employed to integrate a bacterial consortium. A second consortium was integrated with the same bacteria, except for Geobacillus sp. G2. Carbon steel coupons were subjected to batch cultures of both consortia. The corrosion induced by the complete consortium was 10 times higher than that induced by the second consortium, and the ferrous ion concentration was consistently higher in iron-reducing consortia. Scanning electronic microscopy analysis of the carbon steel surface showed mineral films colonized by bacteria. The complete consortium caused profuse fracturing of the mineral film, whereas the non-iron-reducing consortium did not generate fractures. These data show that the iron-reducing activity of Geobacillus sp. G2 promotes fracturing of mineral films, thereby increasing steel corrosion.

Cytotoxic Isoquinoline Alkaloids from Chelidonium majus var. asiaticum

  • Lee, Jun;Shon, Mi-Yae;Jang, Dae-Sik;Ha, Tae-Joung;Hwang, Seon-Woo;Nam, Sang-Hae;Seo, Eun-Kyoung;Park, Ki-Hun;Yang, Min-Suk
    • Journal of Applied Biological Chemistry
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    • v.48 no.4
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    • pp.198-201
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    • 2005
  • Two known isoquinoline alkaloids, (+)-chelidonine (1) and (-)-stylopine (2), were isolated from $CHCl_3$-soluble fraction of whole plants of Chelidonium majus L. var. asiaticum, and their structures were identified by spectroscopic methods and X-ray crystallographic analysis. Two isolates (1 and 2) were examined for their in vitro cytotoxic activities against five human cancer cell lines including DU-145 (prostate), MCF (breast), A549 (lung), HePG2 (liver), and HT-29 (colon) by sulphorhodamine B (SRB) assay.

Screening for Inhibitor of c-myc Expression and Identification of Isolate No.2303

  • Chung, Ji-Hyung;Yeo, Ick-Hyun;Oh, Doo-Whan;Moon, Soon-Ok
    • Journal of Microbiology and Biotechnology
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    • v.5 no.5
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    • pp.264-268
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    • 1995
  • Sulforhodamine B(SRB) assay was performed on the human lung carcinoma, A549 cell line to screen soil microorganisms for production of anti-cancer agent. Among 4, 265 microorganisms, 45 isolates were selected for their cytotoxicity and tested for their effects on the expression of c-myc by RNA slot blot and Northern blot analysis resulting in selection of No.2303 isolate. This No.2303 was identified as Streptomyces sp. by ISP classification and the chemotaxonomic analysis method. NO.2303 inhibited the expression of cmyc in Col0320 DM and A549 cell lines. The culture extract of No. 2303 also inhibited the progression of the cell cycle of Go in NIH 313 cells, implying that the extract also inhibited the expression of c-myc in NIH 313 cell.

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Steel Pile Corrosion in Potential Acid Sulfate Soil (잠재성 특이산성토중 강관말뚝의 부식)

  • Lee, Seung-Heon;Park, Mi-Hyeun;Yoon, Kyung-Sup
    • Proceedings of the Korean Society of Agricultural Engineers Conference
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    • 2003.10a
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    • pp.559-562
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    • 2003
  • The results and discussions of surveyed case site at constructed steel pile in potential acid sulfate soil were as follows. Topography at surveyed site was local alluvial valley and that site soils was classified as BanGog and YuGye series as detailed soil surveyed results in RDA and soil texture was Clay/Clay Loam. Soils pH was neutral, which was average 7.5 but much decreased to average 4.2 after $H_2O_2$ treatment. Organic matter and sulfate ions contents were very rich. The corrosion was severe at ground water fluctuation depth. Deposits colored black were attached to steel pile surface, which because of violent reaction in treatment HCI solution, were guessed as corrosion products (FeS) reduced by sulfate reducing bacteria(SRB). Consequently, main cause was thought microbiologically induced corrosion at this site where there is ground water fluctuation occurring oxidation and reduction reactions in turn and the soil is potential acid sulfate soil.

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Cytotoxic Effects on Human Cancer Cells and Apoptosis of a Sesquiterpene Lactone from Saussure lappa

  • Jin, Mirim;Ryu, Jae-Ha;Ryu, Shi-Yong;Chung, Kyu-Sun
    • Biomolecules & Therapeutics
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    • v.8 no.1
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    • pp.22-26
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    • 2000
  • In order to study the cytotoxic properties of sesquitepenes, dehydrocostus lactone (DL) and costunolide from Saussurea lappa, cytotoxicity was measured by SRB method using various human cancer cell lines. Dehydrocostus lactone(DL) and costunolide exhibited significant cytotoxicity against A-549, SK-OV-3, SK-MEL-2, XF-498 and HCT 15 cells. The U937 human leukemia cells treated with DL showed several apoptotic evidences like chromosome condensation and formation of apoptotic bodies. From the results of FACS analysis, early apoptosis was observed by phosphatidylserine externalization detected by annexin V-FITC. Furethermore, these studies determined hypodiploid contents and effects on the cell phase distribution of DL-treated U937 cells. After exposure of U937 cells to $30\mu\textrm{M}$ DL effectively led to G2/M modified cell cycle distribution within 24hr. These observations suggest that DL can be used efficiently for the cancer treatment.

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