• Title/Summary/Keyword: L $D_{50}$

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Stereospecific Synthesis of Methyl-6-deoxy-$\beta$-L-idopyranoside (Methyl-6-deoxy-$\beta$-L-idopyranoside의 합성)

  • 민신홍;박복구;옥광대
    • YAKHAK HOEJI
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    • v.30 no.6
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    • pp.352-355
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    • 1986
  • Methyl-6-deoxy-$\beta$-L-idopyranoside was prepared in good yield by treatment of methyl 2,3,4-tri-O-benzyl-6-deoxy-$\alpha$-D-xylo-hex-5-enopyranoside with H$_2$ on pd, followed by reaction of Na/NH$_3$ at $-50^{\circ}C$. The ratio of L-idopyranoside and D-glucopyranoside was 7 to 1 in 80.7%. It was confirmed that L-idopyranoside was 1C conformation as being expected.

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Antioxidative and Inhibitory Activities on Tyrosinase of Hippophae rhamnoides Leaf Extracts (비타민나무 잎 추출물의 항산화 및 타이로시네이즈 저해활성)

  • Kim, Jung-Eun;Chae, Kyo-Young;Park, Soo-Nam
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.37 no.3
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    • pp.265-273
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    • 2011
  • In this study, the antioxidative and inhibitory effects on tyrosinase and elastase of Hippophae rhamnoides (H. rhamnoides) leaf extracts were investigated. The ethyl acetate fraction of H. rhamnoides extracts showed more effective free radical (1,1-diphenyl-2-picrylhydrazyl, DPPH) scavenging activity ($FSC_{50}$ = 4.68 ${\mu}g$/mL). Reactive oxygen species (ROS) scavenging activity ($OSC_{50}$) of the aglycone fraction in the luminol-dependent $Fe^{3+}$-EDTA/$H_2O_2$ system was 0.19 ${\mu}g$/mL. The aglycone fraction exhibited more prominent cellular protective effects (${\tau}_{50}$, 133.3 min at 10 ${\mu}g$/mL) in the $^1O_2$-induced photohemolysis of human erythrocytes. The inhibitory effect ($IC_{50}$) of the aglycone fraction on tyrosinase was 54.86 ${\mu}g$/mL, and more effective than arbutin known as whitening agent. These results indicate that fractions of Hippophae rhamnoides extract can be used as antioxidants in biological system, particulaly skin exposed to UV radiation by quenching and/or scavenging $^1O_2$ and other ROS, and protecting cellular membranes against ROS.

Effects of Methanol Extracts from Bamboo(Pseudosasa japonica Makino) Leaves extracts on Lipid Metabolism in Rats Fed High Fat and High Cholesterol Diet (대나무(이대)잎 추출물이 지방 및 고콜레스테롤 식이 급여에 의한 흰쥐의 지방 대사에 미치는 효과)

  • Han, Sung-Hee;Shin, Mee-Kyung
    • Journal of the Korean Society of Food Culture
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    • v.17 no.1
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    • pp.30-36
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    • 2002
  • The effects of Bamboo(Pseudosasa japonica Maki) extracts on serum lipid concentrations were evaluated in rats. Ninety-eight male Sprague-Dawley rats weighing $100{\pm}10g$ were divided into fourty groups and fed high fat diets for four weeks. Experimental groups were administered with following diets; basal fat diet(control), basal and high fat diets with 1% cholesterol and Bamboo(Pseudosasa japonica Maki, -1%, -3%, -5%) extracts. The concentrations of serum triglyceride in rats fed the Bamboo(Pseudosasa japonica Maki) extract, high fat, 1% cholesterol, and Pseudosasa japonica Maki, -1%, -3%, -5% were lower than those in other groups. The concentrations of total cholesterol in the Pseudosasa japonica Maki, -1%, -3%, -5% groups were lower than those in fat diet groups. The concentrations of HDL-cholesterol in serum of the Pseudosasa japonica Maki, -1%, -3%, -5% groups were significantly higer than those of other groups. The levels of LDL-cholesterol in serum of the Pseudosasa japonica Maki, -1%, -3%, -5% groups were tended to be lower than those of other groups. These results suggest that Bamboo(Pseudosasa japonica Maki) extract may reduce elevated levels of serum lipid concentrations in rats fed high fat diets.

Comparison on Compressive Strength of Paraffin Waste Form with H/D Ratio and Loading Rate (붕산함유파라핀 고화체의 직경/높이 및 재하속도에 따른 압축강도비교)

  • 곽경길;유영걸
    • Proceedings of the Korean Radioactive Waste Society Conference
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    • 2003.11a
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    • pp.124-129
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    • 2003
  • In case that the mixing weight ratio of waste form between boric acid and paraffin was 3.3/l, which had been adopted in the concentrate waste drying system (CWDS) of domestic nuclear power plants. Using several specimens with different diameters and heights, 50/100mm specimens. compressive strength were measured. The experiment result showed that the small diameter specimens of compressive strength are increased more than large diameter specimens. (d=50>75>100mm) The average compressive strength of specimens showed that the range from 22.43 $\kg/textrm{cm}^2$ to 38.57$\kg/textrm{cm}^2$ (NRC standard$\geq$4.1 $\kg/textrm{cm}^2$). NRC standard is recommended that the compressive strength test specimens be right circular cylinders, 2 to 3 inches in diameter, with a height-to-diameter(H/D) ratio of approximately two. and compressive strength were increased more than large loading rate. As test result, this conditions are a good agreement, and estimated.

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The Point Load Index of the Daegu Shale and its Relation to the Uniaxial Compressive Strength (대구지역 셰일의 점재하지수 특성 및 일축압축강도와의 상관성)

  • Lee, Younghuy;Youn, Chanho
    • Journal of the Korean GEO-environmental Society
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    • v.10 no.3
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    • pp.37-45
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    • 2009
  • The experimental study was carried out to evaluate the characteristics of the point load index and the uniaxial compressive strength of inherently anisotropic shale in the laboratory. In the testing program the effects of size and the shape on the point load index were investigated both in the axial and diametral direction. In general, the point load index of the shale was constant when the length/diameter (L/D) ratio of the specimen is greater than 1.0 in the diametral direction. The point load index in axial direction shows slight decrease as the L/D ratio is increased and the corner breakage was observed when L/D ratio is greater than unity. The minimum point load index was observed in the bedding angle of $\beta=15^{\circ}{\sim}30^{\circ}$ in the axial point load tests and of $\beta=30^{\circ}$ in the uniaxial compression tests. The relationship between the point load index and the uniaxial compressive strength was linear to ${\sigma}_c=25.0 I_{s(50)}$ for the specimen with the bedding plane angle, $\beta$ at the range of $0^{\circ}{\sim}90^{\circ}$. On the other hand, this relationship was appeared linear to ${\sigma}_c=14.4 I_{s(50)}$ when the bedding angle, $\beta$ is fixed to 90${^{\circ}}$ and this correlation is much different from ${\sigma}c=22 I_{s(50)}, which is generally applied to the rock specimen with no bedding plane in ISRM (1985). The anisotropic strength with different $\beta$ angle shows the shoulder type and this can be suitably modelled by the corrected Ramamurthy'(1993)s equation with the index value of 'n' equal to 3.0.

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An Analysis of Sinking Resistance for Purse Seine - In the Case of the Model Seine with Different d/l - (선망의 침강 저항 해석 - d/l이 다른 모형망의 경우 -)

  • Kim, Suk-Jong;Park, Jeong-Sik
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.34 no.3
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    • pp.274-282
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    • 1998
  • This study deals with sinking resistance for purse seine, in the case of different d/l, ratio of twine diameter and leg length. Experiments carried out on the six types simplified reduced model seines which were made of knotless netting. The nettings were woven in different leg length 4.3, 5.0, 5.5, 6.0, 6.6 and 7.7mm of polyester 28 tex two threads two -ply twine, and each of the seines were named I, II, III, IV, V and Ⅵ seine. Dimension of seine models were 450cm for corkline and 85cm for seine depth, each seines rigged up 160g of float for a floatline and 50g (underwater weight) of lead for a leadline. Experiments were measured in the observation channel of a flume tank at the static conditions Sinking motion was recorded by the two sets TV-camera for VTR which were placed in top and side of the model seine, and reading coordinate carried out by the video digitization system. An analysis were calculated out by simultaneous differential equations for numerical method by Runge - Kutta - Gill sub - routine. The results obtained were as follows: 1. Average sinking speed of seine of seine margin was fastest for Ⅵ seine followed by V, IV, III, II and I seines. 2. The coefficient of resistance for a seine wall was depended upon the ratio of d/l : KD =0.081 (d/l )-0.5 3. The coefficient of resistance for netting bundle was not depended upon the ratio of d/l :CR = 0.91 (), d : Twine diameter, l : Leg length, : Density of netting materals, $\omega$ : Density of water

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Expression of Porcine Epidemic Diarrhea Virus Spike Gene in Transgenic Carrot Plants

  • Kim, Young-Sook;Kwon, Tae-Ho;Yang, Moon-Sik
    • Plant Resources
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    • v.6 no.2
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    • pp.108-113
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    • 2003
  • This study was carried out to obtain basic information for possibility of oral vaccine in carrot using Agrobacteruim -mediated transformation system. The epitope region of porcine epidemic diarrhea virus (PEDV) spike gene which is classified as a member of the Coronaviridae and causes an acute enteritis in pigs was successfully expressed in carrot (Daucus carota) using the Agrobacterium-mediated transformation system. Hypocotyl segments of in vitro germinated plantlets were infected with Agrobacteriun tumefaciens LBA 4404 harboring PEDV spike gene. Embryogenic callus (EC) was induced on MS selection medium with 1 mg/L 2,4-D, 50 mg/L kanamycin and 300 mg/L cefotaxime after 45 days of culture. Subcultured ECs on MS selection medium without 2,4-D were converted to somatic embryos (SE) of various stage; globular, heart and torpedo stage. Putative transgenic embryos were selected on MS medium with 50 mg/L kanamycin and 300 mg/L cefotaxime. Regenerated plantlets from transformed SE were induced on MS medium containing 50 mg/L kanamycin after 30 days of culture. Genomic PCR confirmed the integration of PEDV spike gene into nuclear genome of carrot and northern blot analysis demonstrated the expression of PEDV spike gene in transgenic carrot.

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Antioxidative Effects and Component Analysis of Graviola (Annona muricata) Leaf Extract/Fractions (그라비올라(Annona muricata) 잎 추출물 및 분획물의 항산화 활성과 성분 분석)

  • Park, So Hyun;Kim, Ji Min;Kim, Jin Hwan;Oh, Yoon Soo;Joo, Dong Hee;Lee, Eun Young;Shin, Hyuk Soo;Kim, A Rang;Lee, Sang Lae;Park, Soo Nam
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.43 no.4
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    • pp.309-320
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    • 2017
  • In this study, the antioxidative effects and component analysis of 50% ethanol extract, ethyl acetate fraction and aglycone fraction obtained from Annona muricata leaf were investigated. Free radical scavenging activities were performed by 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay, total antioxidant capacities were estimated using luminol-dependent chemiluminescence assay and $^1O_2$ quenching effects were estimated. Free radical scavenging activities ($FSC_{50}$) of 50% ethanol extract, ethyl acetate fraction and aglycone fraction were 45.6, 29.8 and $18.0{\mu}g/mL$, and total antioxidant capacities ($OSC_{50}$) were 4.4, 1.1 and $2.8{\mu}g/mL$, respectively. As a result of $^1O_2$ quenching experiment, ethyl acetate and aglycone fraction showed similar activities to L-ascorbic acid used as a comparative control. The cellular protective effects of 50% ethanol extract on the $^1O_2-induced$ cellular damage of human erythrocytes were exhibited at concentration-dependent ($5-50{\mu}g/mL$). TLC and HPLC were used to analyse components in the ethyl acetate fraction and aglycone fraction of Annona muricata leaf. In ethyl acetate fraction, rutin (quercetin-3-O-rutinoside), kaempferol-3-O-neohesperidoside, nicotiflorin (kaempferol-3-O-rutinoside), p-coumaric acid were identified. In aglycone fraction, kaempferol was identified. These results suggest that the extracts of Annona muricata leaf have the applicability as antioxidant cosmeceutical ingredients.

Anti-Oxidant Property and Inhibition of Melanin Synthesis of Eight Plant Extracts (수종의 식물수출물의 항산화 및 Melanin 합성 억제효과)

  • Kim, Jae-Young;Lee, Jin-Young;Lee, Wi-Young;Yi, Yong-Sub;Lim, Yoong-Ho
    • Microbiology and Biotechnology Letters
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    • v.38 no.4
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    • pp.414-419
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    • 2010
  • Plants extracts are good resources to find functional compounds for human health. The following eight plants were collected and total phenolic contents were determined. Acer psedo-siebolianum showed the highest phenolic contents, 16.4 mg/g, whereas Cercidiphyllum japonica showed the lowest contents, 1.9 mg/g. The DPPH free radical scavenging capacities of the plant extracts showed high activity in following order : Acer ginnala ($21.3\;{\mu}g/mL$) > Cornus walteri ($23.9\;{\mu}g/mL$) > Distylum racemosum ($29.2\;{\mu}g/mL$) > Castanopsis cuspidata var. Thunbergii ($31.7\;{\mu}g/mL$) > Acer psedo-siebolianum ($34.6\;{\mu}g/mL$) > Thuijopsis dolabrata cv. Aurea ($53.1\;{\mu}g/mL$) > Cercidiphyllum Japonica ($115.2\;{\mu}g/mL$). Also the mushroom tyrosinase inhibitory activities of total extracts were determined at different concentration. D. racemosum extract showed highest (49.1% at 1,000 mg) in inhibitory activity than other seven extracts. The ethanol fraction $IC_{50}$ value: $118.1\;{\mu}g/mL$) from D. racemosum showed more inhibitory activity than ethyl acetate fraction ($IC_{50}$ value: $203\;{\mu}g/mL$). The ethanol fraction on showed no significant cytotoxicity in B16/F1 cells line up to $60\;{\mu}g/mL$. Over $80\;{\mu}g/mL$ of ethanol fraction showed cytotoxicity in B16/F1 cells. The melanin contents of cells were significantly attenuated by ethanol fraction in a dose-dependent manner. The $IC_{50}$ value of ethanol fraction was $75.4\;{\mu}g/mL$.

Cytotoxic Constituents of Diadema setosum

  • Minh, Chau-Van;Kiem, Phan-Van;Huong, Le-Mai;Kim, Young-Ho
    • Archives of Pharmacal Research
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    • v.27 no.7
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    • pp.734-737
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    • 2004
  • 5,8-Epidioxycholest-6-en-3-ol (1), cholesterol (2), glycerol 1-palmitate (3) and glycerol 1,3-dioleate-2-stearate (4) were isolated from the methanol extract of the sea urchin Diadema setosum, which was collected from the Halong sea, Vietnam. Chemical structures were established based on extensive 1D, 2D-NMR, FAB-MS, EI-MS spectroscopic data and GC-MS analysis. The NMR spectral data of compound 1 were reassigned by using HMQC and HMBC. Compound 1 was found to have strong cytotoxic effect against various cancer cell lines, such as KB ($IC_{50}$, 2.0 $\mu\textrm{g}$/mL), FL($IC_{50}$, 3.93 $\mu\textrm{g}$/mL), and Hep-2 ($IC_{50}$, 2.4 $\mu\textrm{g}$/mL) by in vitro assay.