• Journal of Korea Soil Environment Society
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• v.3 no.3
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• pp.87-92
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• 1998

The effect of chemically oxidized intermediates of Polynuclear Aromatic Hydrocarbon (PAH) compounds on the degradation of the parent PAHs was characterized and evaluated for the context of cooxidation. Anthracene and pyrene exhibited extensive degradation (mean percent removal of 57.5%) after 28 days of incubation by introducing the Fenton oxidation intermediate of the PAH compounds, while unoxidized anthracene and pyrene exhibited 12.5% removal The chemical oxidation products can serve as a structually similar analogue substrates for a consortia of soil microorganisms and as a metabolic intermediates in the biodegradation sequence of the parent PAH compounds. These results may be interpreted in the context of cooxidation mechanism whereby high recalcitrant PAH compounds are biodegraded in the soil and suggest a potential tool for bioremediation of PAHs contaminated soils and protection of groundwater.

• Proceedings of the Korea Society of Environmental Toocicology Conference
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• 2001.05a
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• pp.139-139
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• 2001

중금속은 생명체가 필수적으로 요구하는 금속인 것도 있으나 과량 상태에서는 위해성이 나타나는 것으로 알려져 있다. 반면에 수은, 납, 카드뮴 등은 생물에서의 필요성이 밝혀져 있지 않고, 오히려 유해할 뿐이며, 자체 독성 뿐 아니라 대사가 되지 않아 먹이 연쇄를 따라 크게 농축된다(최석영, 1995). 날로 심각해지는 환경오염으로 인한 토양이나 식물의 중금속 오염여부를 파악하려면 자연함유량에 대한 연구가 선행되어야 하지만 국내에선 이에 대한 연구가 거의 없어 중금속 오염평가가 불가능하다. (중략)

• Proceedings of the Korea Society of Environmental Toocicology Conference
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• 1999.05a
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• pp.55-55
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• 1999

• Proceedings of the Korean Society of Crop Science Conference
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• 1999.05a
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• pp.110-111
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• 1999

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2003.09a
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• pp.298-301
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• 2003

생물학적 토양오염 복원기술은 산소와 영양염류를 오염토양에 공급하여 호기성 미생물의 대사작용을 자극함으로써 유류를 생분해 하는 방법으로 널리 사용되고 있다. 유류에 오염된 토양은 혐기성 상태인 경우가 대부분이기 때문에, 호기성 미생물을 이용하기 위해서는 충분한 산소를 공급하여야 하므로 운전비가 많이 드는 단점이 있다. 최근에는 혐기성 미생물을 이용하여 유류오염 토양을 정화하는 방법이 보고되고 있다. 혐기성 생분해 방법은 다소 분해 속도는 느리지만 산소를 공급하지 않기 때문에 경제적인 유류오염토양 복원 방법으로 주목받고 있다. 본 연구에서는 디젤을 사용하여 인위적으로 10000 mg/kg.TPH soil의 농도로 오염시킨 토양 50g을 100$m\ell$ 용적의 vial에 주입하고 하수처리장의 혐기성 소화조 슬러지를 15$m\ell$, 30$m\ell$을 주입하여 배양하였으며 TPH의 분해량과 CH$_4$ 및 $CO_2$ 발생량을 측정하였다. vial의 기상을 $N_2$가스로 치환함으로써 혐기성 상태가 되도록 하였으며, 35$^{\circ}C$에서 90일간 배양하였다. 그 결과, 슬러지를 주입하지 않은 대조군의 경우에는 TPH의 분해가 거의 없었지만, 슬러지를 주입한 경우에는 TPH(Total Petroleum Hydrocarbon)농도가 55% 제거된 것으로 나타났다. TPH의 분해는 CH$_4$ 및 $CO_2$ 발생량과 밀접한 상관관계를 보였다. 본 연구의 결과로부터 하수처리장의 혐기성 소화조 슬러지를 이용한 유류오염 토양의 복원 가능성을 확인할 수 있었다.양에서 유동 가능성이 있는 중금속만을 추출하였다. 분석실험은 토양의 Cd2+ 와 Pb2+를 대상으로 행하여졌으며, 여러 토양에서 추출 분석한 결과를 EDTA분석결과와 비교하였다. 실험결과, 중금속은 매우 신속하게 고분자 자성체와 결합하였고, 그 후 자성체를 외부 자장으로 모은 후 산으로 용해시키고, 결합된 중금속은 Graphite furnace AAS로 분석함으로써 빠르고 효율적으로 분석실험을 수행할 수 있음을 알 수 있었다. 한편, 실험에서 나타난 수치들을 비교 검토한 결과 토양 분석시 sandy soil에서는 자성체를 이용한 분석이 EDTA에 의한 방법보다 더 높은 추출도를 보인 반면, silt 함량이 많은 토양의 경우에서 EDTA분석에서 더 높은 중금속 추출도를 보였다.s 중에서 490nm와 555nm의 복합밴드를 포함하는 OC2 알고리즘(ocean color chlorophyll 2 algorithm)을 사용하는 것이 OC2 series 및 OC4 알고리즘보다 좋은 추정 값을 도출할 수 있을 것으로 기대된다.환경에서는 5일에서 7월에 주로 이 충체의 유충이 발육되고 전파되는 것으로 추측되었다.러 가지 방법들을 적극 적용하여 금후 검토해볼 필요가 있을 것이다.잡은 전혀 삭과가 형성되지 않았다. 이 결과는 종간 교잡종을 자방친으로 하고 그 자방친의 화분친을 사용할 때만 교잡이 이루어지고 있음을 나타내고 있다. 따라서 여교잡을 통한 종간잡종 품종육성 활용방안을 금후 적극 확대 검토해야 할 것이다하였다.함을 보이고 있다.X> , ZnCl$_{3}$$^{-}$같은 이온과 MgCl$^{+}$, MgCl$_{2}$같은 이온종을 형성하기 때문인것 같다. 한편 어떠한 용리액에서

• Microbiology and Biotechnology Letters
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• v.16 no.3
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• pp.238-245
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• 1988

Studies were made on the regulation of chorismate mutase and prephenate dehydratase of a species of Intrasporangium, a phenylalanine producing Actinomycete isolated from soil. Two distinctly regulated species of chorismate mutase, designated CM I and CM IIwere resolved by DEAE Cellulose and DEAE Sephadex A 50 chromatography. The activity of CM II was inhibited by L-tyrosine, whereas that of CM I appeared to be unregulated. Single species of prephenate dehydyatase was also separated in the same purification steps. The activity of the enzyme was strongly feedback inhibited by L-phenylalanine, but by L-tyrosine or L-methionine it was rather slightly stimulated. Synthesis of chorismate mutase was not influenced by the presence of phenylalanine, tyrosine or tryptophan, whereas prephenate dehydratase was found to be subject to strong feedback repression by L-phenylalanine. The rate of repression was 94% at the concentration of 1mM L-phenylalanine but the repression was completely offset by the presence of 5mM tyrosine. The critical regulatory site of the phenylalanine terminal biopathway was, therefore, proved to be the second reaction which was catalyzed by the L-phenylalanine inhibitable and repressible prephenate dehydratase.

• Applied Biological Chemistry
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• v.21 no.3
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• pp.197-203
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• 1978

In order to investigate mechanisms related to the microbial degradation of 3,4-dichloroaniline, it was incubated with a soil fungus, Chaetomium globosum and the following results were obtained. (1) 3,4-Dichloroacetanilide turned out to be the major metabolite, indicating that acetylation is the major scheme. (2) The presence of trace amounts of 3,4-dichloronitrobenzene, 3,3', 4,4'-tetrachloroazo-benzene, 3,4-dichloroaniline is suggestive of the aromatic amine oxidation as the minor pathway. (3) Other metabolites with m/e 112, 114, and 279 were also isolated, but their identities are under investigation. (4) Dechlorination occurring during incubation indicates the possibility of forming hydroxylated and other metabolites.

• Korean Journal of Agricultural and Forest Meteorology
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• v.5 no.3
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• pp.166-171
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• 2003

This study was conducted to investigate the negative physiological impact of saline to roadside trees and to assess the physio-biochemical tolerant characters of woody plants against salinity. Two-year-old Zelkova serrata seedlings treated with 0, 3, 14, 56, and 112 mM NaCl were measured for root collar diameter and cambial electric resistance (as an indication of vitality) and analyzed for carbohydrate and mineral content in the leaves. Z. serrata was affected by NaCl treatments. The vitality of Z. serrata decreased with an increase in NaCl concentration, and the NaCl treatment resulted in nutrient imbalance shown by changes of ion concentration in the tissues. However, relative growth rate for diameter and carbohydrate metabolism in the leaves were not greatly influenced by NaCl treatment. Short-term treatment or low NaCl concentration may not have an observed impact on growth. Nevertheless, roadside trees exposed to saline during the long term would likely show negative effects for growth performance from altered ion concentrations.

• Korean Journal of Soil Science and Fertilizer
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• v.42 no.4
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• pp.301-306
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• 2009

This study was conducted to determine the physiological differences betweenhealthy and wilted plants with respect to nitrate assimilation and ascorbic acid content. Wilting was artificially induced in spinach plants by treating the seeds with nutrient solution containing high nitrogen and low potassium. The plants were cultured in different plots 4 types of media: 1N-1P-1K (control), 6N-1P-0K (0K), 6N-1P-0.5K (0.5K), and 6N-1P-2K (2K). The rate of wilting among the plants was as follows: control, 0%; 2K, 10%; 0.5K, 40%; and 0K, 70%. This shows that under high nitrogen conditions, the lower the amount of potassium provided, higher was the rate of wilting. There were no differences in plant growth among the plants treated with different levels of potassium under high nitrogen conditions.The nitrate content in both the leaves and the roots was higher in plants grown under high nitrogen media than those in the control. Furthermore, the nitrate level decreased with increasing potassium concentration. The ascorbic acid content of spinach under high nitrogen conditions was lower than those of the control.

• Korean Journal of Soil Science and Fertilizer
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• v.36 no.6
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• pp.437-444
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• 2003

Objective of this experiment was to investigate the role of strontium in intracellular processes in mung bean (Vigna radiata L.). Diamine oxidase (DAO) induction by $Sr^{2+}$ appeared to a decrease in putrescine levels correspondently. DAO activities in the hypocotyls were in a range of 0.5 to $1.8unit{\cdot}mg^{-1}\;protein{\cdot}min^{-1}$. The decrease in Put levels in the cotyledons might be partly resulted from Put degradation by DAO. It was observed that the accumulation of spermidine and spermine by $Sr^{2+}$ was in the range of 1 mM to 10 mM. Spermidine levels were 2 to 3 fold higher than in the absence of strontium. The increase in polyamine levels was observed not only on a basis of g fresh weight but also a RNA basis. These results demonstrated that the inhibitory action of $Sr^{2+}$ may be closely related with polyamine metabolism as well as diamine oxidation and polyamine accumulation.