• 환경위생공학
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• 제10권3호
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• pp.45-55
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• 1995

This study was carried out to elucidate the toxic mechanism of cadmium in peripheral nerve. An animal model of cadmium neuropathy was induced by feeding diet containing cadmium to Sprague- Dawley rat (or two weeks. Four weeks aged Sprague- Dawley rats were divided into four groups : normal control group, 10ppm- cadmium treated group, 100ppm- cadmium treated group, 1000ppm- cadmium treated group, reference drug- treated group. All rats were sacrificed at the end of two weeks for assessing the development of cadmium neuropathy, These results obtained were summarized as follows : 1. Cadmium reduced peripheral flow of both acetylcholinesterase and cholinesterase in rat sciatic nerve. 2. The toxic mechanism of cadmium might be the result of an reduction of myo-inositol concentration in peripheral nervous system 3. Reduction in myo-inositol content of peripheral nerve resulted from the inhibition of sodium- Potassium ATPase activity, which is responsible for myo-inositol transport, by cadmium 4. Oral administration of myo-inositol improved the flow of both acetylcholinesterase and cholinesterasenerve in cadmium intoxicated rat. These results suggest that mild cadmium neuropathy might be diagnosed by checking nervous myo-inositol content and oral administraion of myo-inositol might prevent the development of severe cadmium neuropathy with special reference to detective axonal transport.

• Journal of Microbiology and Biotechnology
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• 제22권4호
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• pp.547-554
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• 2012

Chromium is generated from several industrial processes. It occurs in different oxidation states, but Cr(III) and Cr(VI) are the most common ones. Cr(VI) is a toxic, soluble environmental contaminant. Some bacteria are able to reduce hexavalent chromium to the insoluble and less toxic Cr(III), and thus chromate bioremediation is of considerable interest. An indigenous chromium-reducing bacterial strain, Rb-2, isolated from a tannery water sample, was identified as Ochrobactrum intermedium, on the basis of 16S rRNA gene sequencing. The influence of factors like temperature of incubation, initial concentration of Cr, mobility of bacteria, and different carbon sources were studied to test the ability of the bacterium to reduce Cr(VI) under variable environmental conditions. The ability of the bacterial strain to reduce hexavalent chromium in artificial and industrial sewage water was evaluated. It was observed that the mechanism of resistance to metal was not due to the change in the permeability barrier of the cell membrane, and the enzyme activity was found to be inductive. Intracellular reduction of Cr(VI) was proven by reductase assay using cell-free extract. Scanning electron microscopy revealed chromium precipitates on bacterial cell surfaces, and transmission electron microscopy showed the outer as well as inner distribution of Cr(VI). This bacterial strain can be useful for Cr(VI) detoxification under a wide range of environmental conditions.

• 한국물환경학회지
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• 제23권5호
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• pp.766-775
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• 2007

The use of toxic chemicals was extended as the industry in Korea has grown dramatically during the last three decades. However, list of toxic substances and limit concentrations in the water environment are not consistent within management of ambient water, drinking water and industrial effluent. This article suggests the systematic framework to classify toxic substances in the water environment and deriving their effluent limits. The most important factor for decision-making to classify toxic substances is whether their concentrations in the water environment are higher than the reference concentrations, estimated by considering human health risk and ecological risk. Using a risk-based reference concentration, the ambient water quality criterion, it is possible to derive the regulatory limit concentrations of toxic substances in drinking water and in industrial effluent. The goal concentrations in the effluent, which guarantee the human and ecological safety, should be determined with scientific investigation, balancing environmental benefit and economical effect, considering availability of treatment technology and identifying characteristics of wastewater from different industries.

• 대한본초학회지
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• 제20권4호
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• pp.53-60
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• 2005

Objectives : This study was carried out to determine if Dendrobii Herba have protective effect against cell injury induced by various toxic agents in rat kidney slices. Water(DWe) and methanol(DMe) extracts were prepared for this experiment. Methods : Cell injury was estimated by measuring lactate dehydrogenase(LDH). Lipid peroxidation was examined by measuring malondialdehyde, a product of lipid peroxidation. Results : DMe prevented the LDH release by $CCl_4$, menadione, tert-butyl hydroperoxide and mercury treatment in vitro in kidney slices, but DWe prevented the LDH release by $CCl_4$ and mercury. DMe also prevented reduction in GSH and lipid peroxidation induced by $CCl_4$ and mercury. Conclusion : Thus, DMe may have more powerful efficacy on anti-oxidative effects when compared with DWe. And further studies have to be followed concerned with extraction of Dendrobii Herba and its change of effects.

• ALGAE
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• 제27권1호
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• pp.63-70
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• 2012

Algae are sensitive to a wide range of pollutants, and are effective bioindicators in ecotoxicity assessments. Here, we evaluated the sub-lethal sensitivity of the marine dinoflagellate Cochlodinium polykrikoides upon exposure to copper (Cu), lead (Pb), bisphenol A (BPA), and Aroclor 1016 (polychlorinated biphenyl, PCB). Toxic effects were assessed by observations of the reduction in cell counts and chlorophyll a levels after exposure to each toxicant. C. polykrikoides displayed dose-dependent, sigmoidal responses when exposed to the tested chemicals. $EC_{50}$-72 h values for Cu, Pb, BPA, and PCB were 12.74, 46.70, 68.15, and $1.07mg\;L^{-1}$, respectively. PCB, which is an endocrine-disrupting chemical, was the most sensitive, proving its toxic effect on the dinoflagellate. This study provides baseline data on the toxic effects of commonly used heavy metals and endocrine-disrupting chemicals to a marine dinoflagellate.

• 대한한의학회지
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• 제24권3호
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• pp.96-107
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• 2003

Objective : This study was undertaken to determine if Pyunggangaeuljihyul-tang (Pinggankaiyuzhixue-tang, PG) has a protective effect against cell injury induced by various toxic agents in rabbit liver, Methods : Cell injury in vitro was estimated by measuring lactate dehydrogenase (LDH), and that in vivo was estimated by measuring alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activity in serum. Lipid peroxidation was examined by measuring malondialdehyde, a product of lipid per oxidation. Results : PG prevented the LDH release by $CCl_4$, mercury, menadione, and tert-butyl hydroperoxide treatment in vitro in liver slices. The extent of protection by 2% PG was similar to that of $10{\mu\textrm{M}}$ N,N'-diphenyl-p-phenylenedianline, a potent antioxidant, in tert-butyl hydroperoxide-induced LDH release. PG also prevented lipid peroxidation and depletion of cellular ATP induced by Hg. Hg causes motphological changes including cell necrosis and its effect was significantly prevented by PG. When rats were treated intraperitoneatly with 0.5 ml/kg of $CCl_4$, serum alanine aminotransferase and aspartate aminotransferase activities were increased compared with the control, which was significantly inhibited by pretreatment of PG. PG also prevented reduction in GSH and lipid peroxidation induced by $CCl_4$ Conclusion : These results suggest that PG exerts aprotective effect against various toxic agents by its antioxidant action in liver tissues. Thus, PG may be used in prevention and treatment of drug-induced liver cell injury. However, the precise mechanisms of PG protection remain to be determined.

• 대한약리학회지
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• 제21권1호
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• pp.12-26
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• 1985

흰쥐 뇌 미토콘드리아에 의한 $O^{-}_{2}{\cdot}$ 의 생성과 이 radical의 유해작용 및 그 작용기전을 알아보기 위하여 본실험을 수행하였다. Succinate와 antimycin존재하에서 미토콘드리아는 $O^{-}_{2}{\cdot}$을 생성하였으며 이는 SOD-inhibitable NBT환원으로 확인되었다. 동일 조건에서 $H_2O_2$는 일차생성물인 $O^{-}_{2}{\cdot}$의 dismutation으로 생성됨을 알수 있었다. 상기조건에서 미토콘드리아의 막지질이 파괴되었고 반응액에 첨가된 isocitrate dehydrogenase와 적혈구에 각각 불활성화와 용혈이 초래되었다. 이같은 작용은 $Fe^{++}$이 있을때만 관찰 되었다. 그리고 독작용은 superoxide dismutase 혹은 castalase에 의해서 억제되었다. 또한 methional을 첨가하였을 때 ethylene이 생성되었으며 그 생성은 $Fe^{++}$에 의하여 현저히 증가하였다. Ethylene 생성 역시 상기 효소에 의하여 억제되었다. 따라서 미토콘드리아에서 발생된 $O^{-}_{2}{\cdot}$은 거대분자 및 세포에 독성을 나타낼수 있으며 이같은 작용은 $Fe^{++}$의 촉매작용에 의한 $O^{-}_{2}{\cdot}$와 $H_2O_2$의 상호작용으로 발생되는 $OH{\cdot}$ 에 의한것으로 추측되었다. 이상의 결과는 미토콘드리아가 유독성 산소 radical을 발생하므로 조직손상을 시킬 수 있다는 가능성을 시사하는 증거라고 생각되었다.

• 한국환경농학회지
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• 제42권3호
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• pp.253-258
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• 2023

In the environment, chromium often exists in a highly mobile and toxic form of Cr(VI). Therefore, the reduction of Cr(VI) to less toxic Cr(III) is considered an effective remediation strategy for Cr(VI)-contamination. In this study, the biological reduction of hexavalent chromium was examined at the concentrations of 0.01 mM, 0.1 mM, and 1 mM Cr(VI) by the dissimilatory metal-reducing bacterium, Shewanella sp. HN-41 in the presence of ferric-citrate. With the relatively condensed cell densities, the aqueous phase Cr(VI) was reduced at the proportions of 42%, 23%, and 31%, respectively for the 0.01 mM, 0.1 mM, and 1 mM Cr(VI) incubations, while Fe(III)-citrate was reduced at 95%, 88%, and 73%, respectively. Although the strain HN-41 was not considered to reduce Cr(VI) as the sole electron acceptor for anaerobic metabolism in the preliminary experiment, it has been presumed that outer-membrane c-type cytochromes such as MtrC and OmcA reduced Cr(VI) in the presence of ferric-citrate as the electron acceptor. Since this study indicated the potential of relatively high cell density for Cr(VI) reduction, it might propose a bioremediation strategy for Cr(VI) removal from contaminated waters using engineered systems such as bioreactors employing high cell growths.

• 생명과학회지
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• 제9권3호
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• pp.293-299
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• 1999

하이브리도마 세포 배양을 통한 단일 군항체 생산성을 향상시키기 위해서는 배양환경에 의해 유해 대사산물 생산이 어떤 식으로 변화되는가에 대한 이해가 필요하다 세포성장과 단일 군항체 생산을 저해시키는 대사물질 중에 하나인 젖산의 생성을 줄이기 위해, 포도당의 젖산으로의 전환율에 영향을 미치는 인자들에 대해 연구하였다. 초기 포도당 농도가 높을수록, 세포 성장이 빠를 수록 젖산으로의 전환율이 커짐을 알 수 있었다. 또한 세포농도에 따른 비성장속도 변화에 대한 모델식을 기초로 하여 포도당 소비속도만큼 포도당을 공급하는 유가배양을 통해 젖산 생성을 19% 감소시켰고, 적분세포 농도 증가를 통해 단일군항체 생산성을 41% 향상시킬 수있었다.

• KSBB Journal
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• 제13권6호
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• pp.693-699
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• 1998

고정화한 P. phosphoreum의 biolummescence악 독생물질과의 상관관계를 이용한 수계의 독성물질 momtonng 가능성을 조사하였다. P. phosphoreum을 이용한 수계의 독성물질 momtonng을 위한 적정 세포 농도는 최대 biolummescence intensnty를 보인 $O.D_{660}$ 1.0~1.2였으며 이 농도외 세포를 2.5% NaCl 용액에 희석하여 5.0%의 alginateo에 고정화 했을 때 biolummescence 유지도까 가장 좋았다. 이러한 방법으로 monitoring이 가능한 수계의 pH는 6.0~8.0이었다. Free cell과 고정화 세포로 $CdCl_2.H_20, PbCl_2, phenol $그리고 mtrophenol에 대한 bioluminescence를 조사하였을 때 고정화 방법에 의해 독성물질에 대한 민감성0] 증가되었다. 고정화 세포외 경우 각 독성 물질에 따라 20분 이내에 0.01~1.50ppm이하까지 mornitoring이 가능하였다. 뿐만 아니라 speciflC blolurninescence reclucLion rate, biolummescence mtenslLy의 ratio 그리고 Gamma value로 분석함으로서 독성물질의 농도와 biolummescence의 변화를 직선의 관계로 나타낼 수 있어 독성 물질의 농도 예측이 가능하다.