• 한국작물학회지
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• 제27권4호
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• pp.340-360
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• 1982

Because of the continuing rapid increase in pesticide usage in Taiwan, much attention has been focus on pesticide contamination of food and effect of pesticides on human and environmental health. The Plant Protection Center (PPC) conducts safety evaluation of pesticides usee! in Taiwan. The pesticides are classified into different groups based on their acute toxicities. Pesticides which are classified into extremely toxic group are not allow to used on short term crops or the continuously harvest crops. The acute toxicity of pesticides to the beneficial insects are also studied, special attention has been paid to the two predators of rice brown planthopper. 60% of cultivated land in Taiwan are paddy field; therefore, acute fish toxicity was taken into consideration when a pesticide was applied for registration to be used in the paddy. Fish toxicities were evaluated by the dangerous rating value which is the amount of pesticide residue in the field water over the TLM value. Mutagenicity of pesticides was continuously evaluated by using Arne's microbial testing method. Island wide survey of residual levels of pesticides of known pollutants such as chlorinated hydrocarbon . insecticides, mercurial compounds in soil, water and biological samples were carried out constantly. The potential of a new1y Imported esticides to pollute the environment were studied by using model ecosystem. Ecological magnification (EM) of a chemical was calculated from model ecosystem. A chemical was considered as a pollutant when its EM value over 5000. In order to ensure the levels of pesticides residue of the crop within the safety limit. The 'tolerance' of pesticides on different crop groupings were established base on 1) acceptable daily intake value of individual pesticides, 2) average daily consumption of each crop groupings by Chinese person, 3) Actual residues of pesticides. on different crops obtained from supervised trials. Total about 79 pesticides for which the tolerances have been established on different crop groupings. Because the intensive agricultural system was adopted in Taiwan. The phytotoxicity of pesticides to the non-target crops was therefore become one of the important factor in the safety evaluation of pesticide usage. These will include 1) direct injury, 2) injury caused by pesticide polluted irrigation water, 3) injury caused by the pesticide polluted soil, 4) reduction of growth caused by the effect of pesticide on the soil microorganisms. This paper will reviewed all the aspects mentioned in the previous .paragraphs. Most the works have done in Taiwan by the PPC.y the PPC.

• 한국물환경학회지
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• 제23권5호
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• pp.712-722
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• 2007

This study screened three natural ores (iron, mangenase, and zinc), two types of slags, and two elemental metals (elemental iron and zinc) to evaluate transformation characteristics of CAH mixtures [e.g. Carbontetrachloride (CT), 1,1,1-Trichloroethane (1,1,1-TCA), and Perchloroethene (PCE)]. To select an effective metal medium to treat the CAH mixtures, we measured transformation capacities (CAH mass ultimately transformed/mass of metal added) and the degree of dechlorination. We also considered economical efficiency of the metal media by comparing the value, CAH mass ultimately transformed divided by the price of metal medium added. A simplified mathematical model adapting CAH transformation capacity, first-order transformation kinetics, and available mass of metal transforming CAH was developed and used for estimating CAH transformation rate coefficient and longevity of the metal medium. CAH transformation capacity for elemental iron and elemental zinc were 4258~7129 and $4215{\sim}6330{\mu}g\;CAH\;transformed/g$ metal added, respectively, which are a factor of 80~200 higher than slags and natural ores. They also showed a factor of 1.1 to 2.2 greater degree of dechlorination than the others. Among natural ores and slags, Zinc ore showed the highest transformation capacity, $47{\sim}53{\mu}g\;CAH\;transformed/g$ metal added. Although zinc ore have smaller transformation capacity than elemental metals, economical efficiency of zinc ore is a factor of 10~20 greater than elemental metals tested. Consequently, zinc ore would be more economical medium than the others tested in this study. We estimated the pseudo first-order transformation rate of zinc ore was in the order of CT > 1,1,1-TCA > PCE.

• 한국미생물·생명공학회지
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• 제34권3호
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• pp.185-195
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• 2006

산업발달과 인구증가로 인하여 석유계 탄화수소의 사용량이 점차 증가함에 따라 많은 양의 석유계 탄화수소가 환경에 잔류하여 토양과 지하수에 심각한 오염을 야기시키고 있으며, 인체에도 피해를 주게 된다. 유류오염토양을 복원하는 방법 중 생물을 이용한 복원기술은 경제적이고 환경친화적인 기술로서, phytoremediation 방법은 유류오염물질을 분해할 수 있는 미생물과 토양 내의 미생물량을 증가시킬 수 있는 고등식물을 함께 이용함으로써 생물복원기술의 효율을 극대화할 수 있는 방법이다. 토양 내 유류오염물질은 중금속, polychlorinated biphenyl, trichloroethylene, perchloroethylene 등의 오염물질과 달리 식물에 의해 분해 될 수 있기 때문에 유류오염물질 정화효율이 높은 식물종을 선택하는 것이 무엇보다 중요하다. 본 연구에서는 phytoremediation 기법을 이용하여 유류오염토양을 정화하는 과정에서 식물과 근권 미생물을 역할을 밝히고, 이전에 보고된 연구결과를 바탕으로 유류오염토양복원에 효과적인 식물종과 근권미생물을 알아보았다. 토양 내의 유류오염물질은 식물과 근권 미생물에 의해 분해제거되는데, 식물과 근권 미생물은 유류오염물질을 직접 분해하기도 하며 서로의 분해작용을 촉진하는 간접적 역할을 하기도 한다. 유류오염 토양의 정화에 선호되는 식물종은 alfalfa, ryegrass, tall fescue, poplar, corn 등이었으며, 탄화수소를 분해할 수 있는 것으로 밝혀진 미생물종은 주로 Pseudomonas spp., Bacillus spp., Alcaligenes spp. 등이었다. Phytoremediation 방법을 통해 토양 내 유류오염물질의 정화효율을 높일 수 있다는 연구결과가 보고되고 있다. 따라서 phytoremediation 과정에서 식물과 근권 미생물의 역할과 상호작용을 정확히 이해한다면 보다 효과적인 토양복원을 기대할 수 있을 것이다.

• 대한약리학회지
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• 제16권2호
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• pp.45-53
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• 1980

Lipid peroxidation in vitro has been identified as a basic deteriorative reaction in cellular mechanism of aging processes, such as air pollution oxidant damage to cell and to the lung, chlorinated hydrocarbon hepatotoxicity. Many experimental evidences were reported by several investigators that lipid peroxidation could be one of the principle causes for the hepatotoxicity produced by $CCl_4$. It is now reasonably established that $CCl_4$ is activated to a free radical in vivo, that lipid peroxidation occurs very quickly in microsomes prepared from damaged livers, that the peroxidation is associated with loss of enzyme activity of microsomes, and that various antioxidants can protect animals against the hepatotoxic effect of $CCl_4$. Recent studies have drawn attention to some other feature of microsomal lipid peroxidation. Incubation of liver microsomes in the presence of NADPH has led to a loss of cytochrome $P_{450}$. However, the presence of an antioxidant prevented lipid peroxidation and preserved cytochrome $P_{450}$. Decrease of cytochrome $P_{450}$ in microsomes under in vitro incubation can be enhanced by $CCl_4 and these changes were parallel to a loss of microsomal polyunsaturated fatty acid and formation of malonaldehyde. The primary purpose of this experiment was to study the effect of riboflavin tetrabutylate on lipid peroxidation, specially, the relationship between lipid peroxidation and drug metabolizing enzyme system which is located in smooth endoplasmic recticulum as well as the effect of ritoflavin tetrabutylate on drug metabolizing enzyme system of animal treated with $CCl_4$. Albino rats were used for experimental animal. In order to induce drug metabolizing enzyme system, phenobarbital was injected intraperitoneally. $CCl_$ and riboflavin tetrabutylate were given intraperitoneally as solution in olive oil. Microsomal fraction was isolated from liver of animals and TBA value as well as the activity of drug metabolizing enzyme were measured in the microsomal fractions. The results are summerized as following. 1) The secobarbital induced sleeping time of $CCl_4$ treated rat was about 2 times longer than that of the control group. However, the pretreatment with riboflavin tetrabutylate inhibited completely the lengthened sleeping time due to $CCl_4$ treatment. Furthermore TBA value was significantly increased in $CCl_4$ treated rat in comparison to control group tut the increase of TBA value was prevented by the pretreatment with riboflavin tetrabutylate. On the other hand, the activity of hepatic drug metabolizing enzyme was decreased in $CCl_4$ group, however, the pretreatment with riboflavin tetrabutylate also prevented the decrease of the enzyme activity caused by $CCl_4$. 2) The effect of riboflavin tetrabutylate on TBA value and the activity of drug metabolizing enzyme in vitro was similar to in vivo results. Incubation of liver microsome from rat in the presence of $CCl_4$, $Fe^{++}$, or ascorbic acid has led to the marked increase of TBA value, however, the addition of riboflavin tetrabutylate in incubation mixture prevented significantly the increase of TBA value, suggesting the inhibition of lipid peroxidation. In accordance with TBA value, the activity of drug metabolizing enzyme was inhibited in the presence of $CCl_4$, $Fe^{++}$, ascorbic acid but the addition of riboflavin tetrabutylate protected the loss of the enzyme activity in microsome under in vitro incubation.