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Effects of Ephedras Herba on the activity of antioxidant (마황(麻黃) 추출물이 항산화에 미치는 영향)

  • Song, Seong-Min;Lim, Hyung-Ho;Kwon, Ki-Rok;Lim, Tae-Jin;Song, Yun-Kyung
    • Journal of Pharmacopuncture
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    • v.10 no.2 s.23
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    • pp.57-65
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    • 2007
  • Objectives : The purpose of this study was to investigate the antioxidative effects of Ephedrae Herba extract. Methods : Total antioxidant status was examined by total antioxidant capacity(TAC), total antioxidant response(TAR) against potent free radical reactions, total phenolic content, DPPH radical scavenging activities, and the inhibitory effect of the extract on lipid peroxidation in rat liver mitochondria. Results : 1. TAC and TAR of Ephedrae Herba extract at the concentration of 5mg/ml were 3.76 and 1.65 mM Trolox equivalents , respectively. 2. Total phenolic content of Ephedrae Herba extract at the concenuation of 5mg/ml was 3.52 mM gallic acid equivalent. 3. Concentration of Ephedrae Herba extract at which DPPH radical scavenging activity was inhibited by 50% was 0.46mg/ml as compared to 100% by pyrogallol solution as a reference. 4. Ephedrae Herba extract at the concentration of 2mg/ml significantly decreased TBARS concentration by 97%, showing that Ephedrae Herba extract prevented lipid peroxidation at the low concentration. Conclusion : Thus antioxidant effects of Ephedrae Herba extract appear to be due to, at least in part, the prevention from free radicalsinduced oxidation, followed by inhibition of lipid peroxidation.

The Effects of Cement Alkalinity upon the Pore Water Alkalinity and the Chloride Threshold Level of Reinforcing Steel in Concrete

  • Nam Jingak;Hartt William H.;Kim Kijoon
    • Journal of the Korea Concrete Institute
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    • v.16 no.4 s.82
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    • pp.549-555
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    • 2004
  • Cement of three alkalinities (equivalent alkalinities of 0.36,0.52 and 0.97) was employed in fabricating a set of classical G109 type specimens. To-date, these have been subjected to a one week wet-one week dry cyclic pending using 15 w/o NaCl solution. At the end of the dry period, potential and macro-cell current were measured to indicate whether the top reinforcing steel was in the passive or active state. Once this bar became active, the specimen was autopsied and the extent of corrosion was documented. Subsequent to visual inspection, concrete powder samples were collected from the upper region of the top rebar trace; and at a certain times concrete cores were taken from non-reinforced specimens. Using these, determinations were made of (1) critical chloride concentration for corrosion initiation ($Cl_{th}^-$), (2) effective chloride diffusion coefficient ($D_e$), and (3) pore water alkalinity ($[OH^-]$). The pore water alkalinity was strongly related to the alkali content of cement that was used in the mix. The chloride concentration, ($Cl^-$), was greater at active than at passive sites, presumably as a consequence of electro migration and accumulation of these species at active site subsequent to corrosion initiation. Accordingly, ($Cl^-$) at passive sites was considered indicative of the threshold concentration fur corrosion initiation. The $Cl_{th}^-$ was increased with increasing Time-to-corrosion ($T_i$). Consequently, the HA(High Alkalinity) specimens exhibited the highest $Cl_{th}^-$ and the NA(Normal Alkalinity) was the least. This range exceeds what has previously been reported in North America. In addition, the effective diffusion coefficient, $D_e$, was about 40 percent lower for concrete prepared with the HA cement compared to the NA and LA(Low Alkalinity) ones.

Effect of seeding ratio on acidogenic biokinetics in high ammonia concentration

  • Yang, Keun-Young;Shin, Seung-Gu;Hwang, Seok-Hwan
    • 한국생물공학회:학술대회논문집
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    • 2005.04a
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    • pp.65-66
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    • 2005
  • Anaerobic digestion is one of the well-known methods for biological treatment handling of concentrated organic matter such as swine $wastewater.^{1)} The anaerobic digestion can reduce organic loading but also hydrolyze non-biodegradable organic $matter.^{2)}$ The feces from the scrapper-type barn are usually collected to make compost and the urine is discarded with swine-slurry wastewater by ocean-dumping or treated by biological methods. The lagoon, aerobic digestion, anaerobic digestion, SBR, $A^{2}/O$, and UCT have been applied for treating swine $wastewater.^{3)} In this study, as a result of the analysis of swine wastewater, the total and soluble chemical oxygen demand was 130g/L and 60g/L, respectively. And the volatile fatty acid as chemical oxygen demand equivalent was 45g/L, which was 75% of soluble chemical oxygen demand. Before everything else, ammonia nitrogen concentration was 6.5 g/L. From biochemical acidogenic potential test, it was concluded that the enhanced acidification process to manage swine waste should be operated in the ammonia nitrogen concentration of less than 1.2 g/L. In the result of seeding ratio experiments with artificial $wastewater^{4)}, the lag period of acidogens was taken the long time because of the inhibition by the $ammonia^{5)}$, however no difference of period by the seeding ratio was not shown. The Haldane-based biokinetics were also evaluated using a method of fourth order Runge-Kutta $approximation.^{6,7)}$ The nonlinear least squares (NLLS) method with a 95% confidence interval was also used. The ranges of maximum microbial growth rate, ${/mu_{max}}$, and half saturation coefficient, $K_{s}$, for acidogenesis of various seeding ratio with artificial wastewater were 6.1 ~ 12.6 $d^{-1}$ and 45,000 ~ 53,500 mg glucose/L, respectively. Also, the methanogenic microbial yield coefficient, Y, and microbial decay rate coefficient, $k_{d}$, and inhibition substrate concentration, $K_{si}$, for the reactors were determined to be 0.32 ~ 0.465 ${/mu}g$/mg glucose; 0.42 ~ 1.01 $d^{-1}$ and 51,500 ~ 55,600 mg glucose/L, respectively.

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A Study of Heavy Metal Pollutants in the Respirable Dust in Seoul Area (호흡성분진중의 중금속 오염도에 관한 조사연구)

  • Lim, Young-Wook;Chung, Young
    • Journal of Korean Society for Atmospheric Environment
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    • v.5 no.1
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    • pp.68-78
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    • 1989
  • The heavy metal of suspended particulates with human health has long been studied in environmental interest concerned. This study was intended to identify harmful heavy metals of the ambient air borne dusts which were related with the respirable sizes in the aerodynamics. Two sampling sites were selected comparatively; one was in the Shinchon area, which is the commercial district with heavy traffic and the other site was in the Bulgwang area which is residential area. The supended particulates were sampled by high volume air sample with 6 cascade impactor stages. The heavy metals in terms of As, Cd, Cr, Cu, Fe, Hg, Mn, Ni, Pb, Se, V and Zn were determined by stomic absorption spectrometry or inductively coupled plasma emission spectrometry. The samples weretaken bimothly for seven consecutive days from May 1987 to March 1988. The annual average concentration of the respirable suspended dust of which diameter is less than 10$\mum$ was 152.59 $\mug/m^3$ of the Shinchon air samples; the respirable dust was equivalent to approximately 85% of the total suspended particulates. The annual average concentration of the respirable suspended dust of the Bulgwang air samples was 112.56 $\mug/m^3$; that was approximately 86% of the total suspended particulates. The concentration of heavy metals was investigated in relation to the particle size. The concentration of Cr, Fe, Mn and V were tended to be much more in the coarse particles than in the fine particles. Cd and Pb in the fine particles were more than in the coarse particles. In the partial correlation coefficients; in the Shinchon area, high correlations among Fe, Se and Mn were determined; it is assumed that those sources would be originated from coal, gasolineand diesel. In Bulgwang area, would be high correlation among Fe, Se, Hg and Mn considered to be originated from coal, Bunker-C and heavy oil as well. From the above results, the hazardous heavy merals in air should be measured and controlled in originally their sources.

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Study on Analysis Algorithm of Search Direction and Concentration of Spatial Information (공간정보 탐색 방향과 집중정도 분석 알고리즘에 관한 연구)

  • Kim, Jong-Ha
    • Korean Institute of Interior Design Journal
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    • v.25 no.4
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    • pp.80-89
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    • 2016
  • The analysis of spatial search direction and its concentration through eye movement can produce some useful data in that it enables to know the features of space elements and their effects on one another. The results by analysing the search features and concentration of spatial sections through the eye-tracking in shops in a department store makes it possible to define the followings. First, the features of 'eye's in & out' could be estimated through the division of sections by the characteristics of those shops and the extraction of central point based on the decision of continuative observation. The decision of continuative observations enabled to analyse the frequency of observation data which can be considered to be 'things watched longtime' and the stared points that is equivalent to 'things seen very often', by which the searching characteristics of spatial sections could be estimated. Second, as with the eye's [in], the right shops had 0.6 times more (3.5%) than those left and as with the eye's [out] the left ones had 0.6 times more (3.5%). It indicates that [in, out] of the right and the left shops had the same difference, which lets us know that with starting point of the middle space, [in] and [out] were paid more attention to the right shops and the left shops respectively. Third, as with the searching directions by section, the searching times [2.9 times] from [B] to [A] were than that [2.6 times] from [A] to [B]. It was also found that the left shops had more searching direction toward [C, D] than the right ones and that those searching activities at the left shops were more active. Fourth, when the searching directions by section are reviewed, the frequency of searching from [B] to [A] was 2.9 and that of the other way 2.6. Also the left shops were found to have more searching direction toward [C, D] than the right ones and those searching activities at the left shops were estimated to be more active.

A Study on the Chemical Composition and Hypocholesterolaemic Effect of Aster scaber and Ixeris dentata (참취 및 씀바귀의 성분조성과 혈청 지질저하작용에 대한 연구)

  • 임상선;이종호
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.26 no.1
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    • pp.123-129
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    • 1997
  • The effects of Aster scaber(Cham chyi) and Ixeris dentata(Sumbagui) of composite were studied on lipid metabolism in rats. Thirty rats were divided into five groups and fed diets containing 1% cholesterol, 0.25% sodium cholate, 10% coconut oil and 5% lard(control group) for 4 weeks. For each experimental diet added was 5% plant powder or extract of the plant which was equivalent to 5% Plant powder by dry weight. The lipid components of serum were assayed. The concentration of the total cholesterol was significantly lower in Cham chyi, and Sumbagui powder and the extract groups of those powder than the control group. The concentration of HDL-cholesterol was significantly higher in rats fed Cham chyi and Sumbagui powder than the control group. The concentration of LDL, LDL-cholestrol, VLDL and chylomicron were comparatively lower in Cham chyi and Sumbagui powder groups than those in the control group. The concentration of seum triglyceride was lower in Cham chyi powder fed group than the control group.

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Antioxidant and Hepatoprotective Effects of Tomato Extracts

  • Rhim, Tae-Jin
    • Korean Journal of Plant Resources
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    • v.19 no.6
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    • pp.649-654
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    • 2006
  • The objective of present study was to investigate the anti oxidative and hepatoprotective effects of tomato extracts. Total antioxidant capacity and total antioxidant response were 5.5 and $19.8{\mu}g$ Trolox equivalent per mg of tomato extract, respectively. DPPH radical scavenging activity of tomato extracts ($10mg\;ml^{-1}$) was 70% as compared to 100% by pyrogallol solution as a reference. The effect of the tomato extracts on lipid peroxidation was examined using rat liver mitochondria induced by iron/ascorbate. Tomato extracts at the concentration of $0.5mg\;ml^{-1}$ significantly decreased TBARS concentration. Tomato extracts prevented lipid peroxidation in a dose-dependent manner. The effect of the tomato extracts on reactive oxygen species (ROS) generation was examined using cell-free system induced by $H_2O_2/FeSO_4$. Addition of $1mg\;ml^{-1}$ of tomato extracts significantly reduced dichlorofluorescein (DCF) fluorescence. Tomato extracts caused concentration-dependent attenuation of the increase in DCF fluorescence, indicating that tomato extracts significantly prevented ROS generation in vitro. The effect of tomato extracts on cell viability and proliferation was examined using hepatocyte culture. Primary cultures of rat hepatocytes were incubated with 1mM tert-butyl hydroperoxide (t-BHP) for 90 min in the presence or absence of tomato extracts. MTT values by addition of tomato extracts at the concentration of 2, 10, and $20mg\;ml^{-1}$ in the presence of t-BHP were 13, 33 and 48%, respectively, compared to 100% as control. Tomato extracts increased cell viability in a dose-dependent manner. These results demonstrate that tomato extracts suppressed lipid peroxidation and t-BHP-induced hepatotoxicity and scavenged ROS generation. Thus antioxidant and hepatoprotective effects of tomato extracts seem to be due to, at least in part, the prevention from free radicals-induced oxidation, followed by inhibition of lipid peroxidation.

Effects of Operating Parameters on the Removal Performance of Ammonia Nitrogen by Electrodialysis (전기투석에 의한 암모니아성질소의 제거 시 운전인자의 영향)

  • Yoon, Tae-Kyung;Lee, Gang-Choon;Jung, Byung-Gil;Han, Young-Rip;Sung, Nak-Chang
    • Clean Technology
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    • v.17 no.4
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    • pp.363-369
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    • 2011
  • To evaluate the feasibility of electrodialysis for ammonia nitrogen removal from wastewater, the effects of operating parameters such as diluate concentration, applied voltage and flow rate on the removal of ammonia nitrogen were experimentally estimated. The removal rate was evaluated by measuring the elapsed time for ammonia nitrogen concentration of diluate to reach 20 mg/L. Limiting current density (LCD) linearly increased with ammonia nitrogen concentration and flow rate. The elapsed time was linearly proportional to initial concentration of diluate. Due to relatively large equivalent ion conductivity and ion mobility of ammonia nitrogen, the removal rate increased consistently with flow rate. Increase in the applied voltage gave positive effect to removal rate. From the operation of the electrodialysis module used in this research, the flow rate of 3.2 L/min and 80~90% of applied voltage for LCD are recommended as the optimum operating condition for the removal from high concentrate ammonia nitrogen solution.

Estimation of Occupational Health Standard by Relationship between Airborne Lead Concentration by Particle Size and Lead in Blood (공기중 납입자의 크기 특성과 혈액중 납농도와의 관계에 의한 허용농도 측정)

  • Park, Dong-Wook;Paik, Nam-Won
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.6 no.2
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    • pp.265-271
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    • 1996
  • This study was conducted to investigate distribution of lead particles by operation of industry, to evaluate the effect of particle size on the absorption to workers, and to recommend the Occupational Health Standard for lead. Total lead concentrations in the secondary smelting industry were higher than those in the battery and litharge manufacturing industry. Total lead concentrations in other industries except radiator manufacturing industry exceeded the standard of $50{\mu}g/m^3$. Only radiator manufacturing industry indicated lead concentrations significantly lower than those in other industries(p<0.05). Average blood lead level of workers was $85.1{\mu}g/dl$ in secondary smelting manufacturing, $51.3{\mu}g/dl$ in the battery manufacturing, and below $40{\mu}g/dl$ in the litharge and radiator manufacturing industry. Blood lead levels of workers by industry were significantly different(p<0.05). From relationship between airborne lead concentrations by size and lead in blood, confidence limits of airborne lead concentration equivalent to $40{\mu}g/dl$ of permissible limit in blood, was $147.9-489.8{\mu}g/m^3$ as total lead and $28.8-79.4{\mu}g/m^3$ as ACGIH-RPM. It is recommended that two separate occupational health standards for lead should be established by particle size. Airborne concentration of $150{\mu}g/m^3$ as fatal lead dust and $30{\mu}g/m^3$ as respirable lead dust was recommended.

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A Study on the Antitumor Activity of Panax ginseng (고려인삼의 항암효과에 관한 연구)

  • Hwang, Woo-lk
    • Journal of Ginseng Research
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    • v.17 no.1
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    • pp.52-60
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    • 1993
  • Panax ginseng has been extensively used in the traditional oriental medicine as a restorative, tonic and Prophylactic agent. Recently, several reports regarding to anticancer effects of Panax ginseng has accumulated. These studies emphasized the fact that the anticancer activities might be due to a glycoside group called ginsenoside or pan.u saponin which has a water soluble characteristic. However, the authors and collaborates demonstrated that a highly lipid soluble component in extract of Panax ginseng roots contains a considerable cytotoxic activities against marine leukemic cells (L1210, P388) and human censer cells (HRT-18, HT-29, HCT48). This study was devised to observe the cytotoxic activities of Petroleum-ether extract of Panax giuseng roots (crude GBD and its Partially Purified fraction from silicic acid column chromatography (7 : 3 GX) against sarcoma-180 (5-180) and Walker carcinosar- coma 256 (Walker 256) in vivo, and murine leukemic Lymphocytes (L1210) and human rectal cancer cells (HRT-18) and human colon cancer cells (HT-29 and HCT48) in vitro. Each cell-line was cultured in medium containing serial concentration of the crude GX or 7 : 3 GX in vitro. A highly lipid soluble compound in the extract of Panax ginseng root was cytocidal to murine leukemic cells and human colon and rectal cancer cells in vitro. In the meantime, ginseng saponin derivatives did not have cytotoxic effects at its corresponding concentration. The growth rates of the cancer cells in medium containing ginseng extracts were inhibited gradually to a significant degree roughly in proportion to the increase of the extract concentration. The cytotoxic activity of 7 : 3 GX was about 3 times more potent than that of crude GX, one unit of cytotoxic activity against L1210 cells being equivalent to 2.54 Ug and 058 Ug for the crude GX and 7 : 3 GX, respectively. The Ri value of the active compound on silica- gel thin layer chromatography with petroleum-ether/ethyl ether/acetic acid mixture (90 : 10 : 1, v/v/v) as a developing so lvent was 053. While, the Panaxydol and Panaxynol as active compounds were purified from Petroleum-ether extract of Panax ginseng root by Drs. Ahn and Kim, and author found out that the one unit of cytotoxic activity of the Panaxydol and Panaxynol against L1210 cells being equivalent to 056 Ug and 0.3918 respectively. The survival times of mice inoculated with S-180 cells were extended about 1.5 to 2 times by the 7 : 3 GX treatment compared with their control group. The significantly decreased hemoglobin values of rats after inoculation with Walker 256 were recovered to normal range by oral administration of the crude Gt The synthetic levels of protein, DNA and RNA in human colon and rectal cancer cells were significantly diminished by treatment with the crude GX, which can explain a part of the origin of its anticancer activity.

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