• Title/Summary/Keyword: Toxic reduction

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Toxic Effects of Serpentine Soils on Plant Growth

  • Kim, Jeong-Myeong;Shim, Jae-Kuk
    • Journal of Ecology and Environment
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    • v.31 no.4
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    • pp.327-331
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    • 2008
  • Serpentine soils are distributed in a small area in Korea, and generally exhibit high contents of Ni, Cr, Fe, Mn, Co and Mg. We investigated the growth of woody plants and herbs in the Andong serpentine area, Korea. Pinus densiflora and P. rigida growing on serpentine soils have high contents of Fe, Mg, Ni and Co, with contents approximately twice as high as those of non-serpentine plants. Tree species on serpentine soil also had lower ratios of tree height/DBH than trees in a control area. In greenhouse culture experiments on two bodenvag herb species, Setaria viridis and Cymbopogon tortilis, the biomass of the plants was significantly affected by soil type but not by seed origins. After 66 days, the growth of S. viridis and C. tortilis seedlings was significantly inhibited in serpentine soil, and the dry weight of each species showed significant negative correlations with soil heavy metal contents (Ni, Co and Cr). These results suggest that the growth of plants was inhibited by properties of the serpentine soil, and in particular, their high heavy metal concentration, which induced dwarfing in woody plants and reduction of total plant biomass in herbs.

Natural dyeing of cow leather with cochineal (코치닐을 활용한 우피의 천연염색)

  • Kim, Sangyool
    • The Research Journal of the Costume Culture
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    • v.24 no.6
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    • pp.817-824
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    • 2016
  • The introduction of natural dyes into modern dye houses is very promising green chemistry concept that should be popularized more to reduce the dependency of leather dyeing on some toxic and non-biodegradable synthetic dyes. In this study, the properties of dyeing of cochineal on cow leather were evaluated. The proper dyeing conditions were identified with dye uptake (K/S values) depending on the colorant concentration, dyeing duration, dyeing temperature, and dye bath pH. For the proper mordanting conditions, color changes for different mordants were observed as $La^{*}b^{*}$ and H V/C values. Color fastness (light, rubbing, and dry cleaning) was also examined. Additionally, antibacterial properties and UV protection were examined. The results were as follows: The optimized dyeing conditions were 300% o.w.f., $40^{\circ}C$, 40 min., and pH 5. The cow leather color was red in the absence of mordanting, while it was red purple after being mordanted with Al and Cu, and purple mordanted with Fe. The K/S value of cow leathers increased in the order of the dyeing using $AlK(SO_4)_2$ > $CuSO_4$ > $FeSO_4$. The colorfastness to light and rubbing were reduced compared to original (untreated) cow leather. However dry cleaning fastness was very satisfactory, with a 4~5 rating. The dyed and pre-mordanting dyed cow leather showed excellent antibacterial properties.

Pollution of Heavy Metals in Paddy Soils Around the Downstream Area of Abandoned Metal Mine and Efficiency of Reversed Soil Method as Its Remediation (폐금속광산 하부 농경지 토양의 중금속오염과 그 복구방법으로서 반전객토의 효율성)

  • Na, Choon-Ki;Lee, Mu-Seong;Chung, Jae-Il
    • Economic and Environmental Geology
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    • v.30 no.2
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    • pp.123-135
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    • 1997
  • In order to investigate the dispersion patterns and contamination level of heavy metals in the soil-ecosystem and to evaluate the efficiency of soil remediation by reversed soil method, soils and plants were collected from the Dongjin Au-Ag-Cu mine area and analysed for heavy metals. The dispersion patterns of heavy metals in soils and plants show that heavy metal pollutions caused by waste rump around Dongjin mine are mainly found in the vicinity of the waste rump and in the southward slanting of mine. Toxic metallic pollutants from the mine influence heavy metal contents in paddy soils in downstream area, and may be a potential sources of heavy metal pollution on crop plants. Soil samples collected from the remediated rice farming field by reversed method show similar levels of heavy metal content to those from the polluted rice farming field, but topsoil enrichment of heavy metals are not found. Heavy metal contents of the rice plants collected from remediated rice farming field are significantly lower than those from polluted rice farming field, and it suggests that the reversed soil method is effective for the reduction of bioavailability of heavy metals.

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Laboratory-scale Microcosm Studies in Assessing Enhanced Bioremediation Potential of BTEX and MTBE under Various Electron Acceptors in Contaminated Soil

  • 오인석;이시진;장순웅
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 2003.09a
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    • pp.368-371
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    • 2003
  • Accidental release of petroleum products from underground storage tank(USTs) is one of the most common causes of groundwater contamination. BTEX is the major components of fuel oils, which are hazardous substances regulated by many nations. In addition to BTEX, other gasoline consituents such as MTBE(methyl-t-buthyl ether), anphthalene are also toxic to humans. Natual attenuation processes include physic, chemical, and biological trasformation. Aerobic and anaerobic biodegradation are believed to be the major processes that account for both containment of the petroleum-hydrocarbon plum and reduction of the contaminant concentrations. Aerobic bioremediation has been highly effective in the remediation of many fuel releases. However, Bioremediation of aromatic hydrocarbons in groundwater and sediments is ofen limited by the inability to provide sufficient oxygen to the contaminated zones due to the low water solubility of oxygen. Anaerobic processes refer to a variety of biodegradation mechanisms that use nitrate, ferric iron, sulfate, and carbon dioxide as terminal electron accepters. The objectives of this study was to conduct laboratory-scale microcosm studies in assessing enhanced bioremediation potential of BTEX and MTBE under various electron accepters(aerobic, nitrate, ferric iron, sulfate) in contaminated Soil. these results suggest that, presents evidence and a variety pattern of the biological removal of aromatic compounds under enhanced nitrate-, Fe(III)-, sulfate-reducing conditions.

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Causes of Fish Kill in the Urban Streams I - Field Surveys and Laboratory Experiments (도시 하천에서의 어류 폐사 원인 분석 I - 일반조사 및 실험)

  • Lee, Eun-hyoung;Seo, Dongil;Hwang, Hyun-dong;Yun, Jin-hyuk;Choi, Jae-hun
    • Journal of Korean Society of Water and Wastewater
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    • v.20 no.4
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    • pp.573-584
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    • 2006
  • This study was carried out to investigate the causes of fish kills in the Yudeung Stream in Daejeon, Korea using literature reviews, governmental and our water quality monitoring data of the study site, rainfall data, intensive water quality monitoring during rainfall events, sediment pollutant contents and laboratory bioassay tests. Fish kill in urban streams can be caused by combined effect of reduction in dissolved oxygen concentration, increase in toxic material or increase in turbidity in waterbody due to introduction of surface runoff or effluent of combined sewer overflows after rainfall from the watershed areas. Despite of extensive and intensive field surveys and laboratory tests, it was found that those conventional methods have limitations to identify causes of fish kills in urban streams. It would be necessary to use dynamic water quality modeling to predetermine the range and level of water pollution in the stream and automatic water quality monitoring system that can collect water samples and detect water quality continuously.

Decomposition of PVC and Ion exchange resin in supercritical water

  • Lee, Sang-Hwan;Yasuyo, Hosgujawa;Kim, Jung-Sung;Park, Yoon-Yul;Hiroshi, Tomiyasu
    • Proceedings of the Korean Environmental Sciences Society Conference
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    • 2005.05a
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    • pp.267-271
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    • 2005
  • This experiment was carried out at 450"C, which is relatively lower than the temperature for supercritical water oxidation (600-650$^{\circ}C$). In this experiment, the decomposition rates of various incombustible organic substances were very high. In addition, it was confirmed that hetero atoms existed in organic compounds and chlorine was neutralized by sodium(salt formation).However, to raise the decomposition rate, relatively large amount of sodium nitrate(3-4 times the equivalent weight) was required. When complete oxidation is intended as in the case with PCB, the amount of oxidizer and decomposition cost is important. But when vaporization reduction is required as in the case with nuclear wastes, the amount of radioactive wastes increases instead. But as can be seen in the result of XRD measurement, unreacted sodium nitrate remained unchanged. If oxidation reaction of organic substance simply depends on collision frequency, unreacted sodium nitrate can be recovered and reused, then oxidation equivalent weight would be sufficient. In the gas generated, toxic gas was not found. As the supercritical water medium has high reactivity, it is difficult to generate relatively low energy level SO$_{X}$, and NO$_{X}$.

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Reduction of Thermal Radiation from Flare Stack by Flare Gas Recovery Unit (폐가스 회수장치를 이용한 플레어스택의 복사열 감소)

  • Lee, Heon-Seok;Lee, Dong-Heuk;Yoo, Jin-Hwan;Park, Chul-Hwan;Ko, Jae-Wook
    • Journal of the Korean Institute of Gas
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    • v.15 no.1
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    • pp.40-45
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    • 2011
  • During process operations, overpressure can be caused by operator's error or malfunction of the device. To prevent this overpressure, gas was released through blowdown system. Because most of released gases are the hydrocarbon mixture and have flammable and toxic properties, the gas is released after burning in flare stack. The increase of scale and complexity of plant requires higher or additional flare stacks. This study tried to solve this problem through flare gas recovery system.

Antioxidants May Protect Cancer Cells from Apoptosis Signals and Enhance Cell Viability

  • Akan, Zafer;Garip, Ayse Inhan
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.8
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    • pp.4611-4614
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    • 2013
  • Quercetin is one of the most abundant dietary flavonoids widely present in many fruits and vegetables. Previous in vitro studies has shown that quercetin acts as an antioxidant and anti-inflammatory agent and it has potent anticarcinogenic properties as an apoptosis inducer. In this study we examined apoptotic effects of quercetin on the K562 erythroleukemia cell line. K562 cells were induced to undergo apoptosis by hydrogen peroxide. Cell viability and apoptosis level were assessed by annexin V and PI staining methods using flow cytometry. Viability of K562 cells was increased by low dose of quercetin (5-100 ${\mu}M$) for 3 hours. High doses of quercetin proved toxic (100-500 ${\mu}M$, 24 hours) and resulted in decrease of K562 cell viability as expected (p<0.01). As to results, 100 ${\mu}M$ quercetin was defined as a protective dose. Also, K562 cell apoptosis due to hydrogen peroxide was decreased in a dose dependent manner. As indicated in previous studies, reduction of superoxides by free radical scavengers like quercetin could be beneficial for prevention of cancer but consumption of such flavonoids during cancer treatment may weaken effects of chemotherapeutics and radiotherapy. Especially cancer patients should be carefully considered for traditional phytotherapy during cancer treatment, which can lead to controversial results.

Role of cysteine at positions 67, 161 and 241 of a Bacillus sphaericus binary toxin BinB

  • Boonyos, Patcharaporn;Soonsanga, Sumarin;Boonserm, Panadda;Promdonkoy, Boonhiang
    • BMB Reports
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    • v.43 no.1
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    • pp.23-28
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    • 2010
  • Binary toxin consisting of BinA and BinB from Bacillus sphaericus is toxic to mosquito larvae. BinB is responsible for specific binding to the larval gut cell membrane while BinA is crucial for toxicity. To investigate functional role of cysteine in BinB, three cysteine residues at positions 67, 161, and 241 were replaced by alanine or serine. Mutations at these positions did not affect protein production and overall structure of BinB. These cysteine residues are not involved in disulfide bond formation between BinB molecules. Mosquito-larvicidal assays revealed that C67 and C161 are essential for toxicity, whereas C241 is not. Mutations at C67 and C161 resulted in weaker BinA-BinB interaction. The loss of toxicity may be due to the reduction of interactions between BinA and BinB or BinB and its receptor. C67 and C161 could also play a part during conformational changes or internalization of the binary toxin into the target cell.

The Design and Fabrication of μCCA-μGI Device for Toxicity Evaluation of Acetaminophen (아세트아미노펜 독성평가를 위한 μCCA-μGI 디바이스의 개발)

  • Chang Jung-Yun;Shuler Michael L.
    • Journal of Pharmaceutical Investigation
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    • v.36 no.4
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    • pp.263-269
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    • 2006
  • Deficiencies in the early ADMET(absorption, distribution, metabolism, elimination and toxicity) information on drug candidate extract a significant economic penalty on pharmaceutical firms. Microscale cell culture analogue-microscale gastrointestinal(${\mu}CCA-{\mu}GI$) device using Caco 2, L2 and HEp G2/C3A cells, which mimic metabolic process after absorption occurring in humans was used to investigate the toxicity of the model chemical, acetaminophen(AAP). The toxicity of acetaminophen determined after induction of CYP 1A1/2 in Caco 2 cells was not significant. In a coculture system, although no significant reduction in viability of HEp G2/C3A and L2 cells was found, approximately 5 fold increase in the CYP 1A1/2 activity was observed. These results appear to be related to organ-organ interaction. The oral administration of a drug requires addition of the absorption process through small intestine to the current ${\mu}CCA$ device. Therefore, a perfusion coculture system was employed for the evaluation of the absolution across the small intestine and resulting toxicity in the liver and lung. This system give comprehensive and physiologic information on oral uptake and resulting toxicity as in the body. The current ${\mu}CCA$ device can be used to demonstrate the toxic effect due to organ to organ interaction after oral administration,