• 한국미생물·생명공학회지
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• 제18권1호
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• pp.31-34
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• 1990

중온성과 고온성인 황산염 환원세균들을 사용하여 dibenzothiophene, 원유 및 Bunker C 유의 탈황실험을 하여 중온성인 분리균주 Desulfovibrio desulfuricans M6는 dibenzothiophene, crude oil를 42, 17 까지 탈황시켰으며, 고온성은 Desulfovibrio thermophilus에서 dibenzothiphene Bunker C 유를 각각 68, 33 탈화시켜, 황산염 환원세균에 의한 석유의 탈황 가능성을 보였다. 또한 Desulfovibrio 속과 Desulfotomaculum 속의 탈황 능력의 차이로부터 탈황기작이 hydrogenase와 환원력 원인 수소가 관련이 있다는 것을 알았다.

• 청정기술
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• 제16권1호
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• pp.12-18
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• 2010

본 연구의 목적은 산화탈황 공정의 부산물인 dibenzothiophene sulfone의 분해반응용 KF/MgO 촉매를 개발하는 것이다. MgO 지지체에 KF를 담지시켜 KF/MgO 촉매를 제조하였다. KF 담지량 및 소성 효과 등이 촉매 특성에 미치는 영향을 BET표면적, XRF, XRD, 이산화탄소 승온탈착 실험 등을 통해서 분석하였다. Dibenzothiophene sulfone을 biphenyl 과 이산화황으로 분해하는 반응에서의 촉매 특성을 조사하였다. MgO 촉매에 KF를 담지하면 DBTS 분해반응 활성이 증가하였다. KF/MgO 촉매를 제조하여 373 K에서 건조과정만 거친 촉매의 활성이 고온에서 소성을 거친 촉매의 활성보다 높았으며, 이는 fluoride 이온 ($F^-$)이 염기도를 증가시키는 역할을 하기 때문으로 판단된다. KF를 10 wt% 담지한 촉매가 dibenzothiophene sulfone 분해 반응에서 가장 뛰어난 활성을 보였다.

• 상하수도학회지
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• 제25권4호
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• pp.527-534
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• 2011

In this research, the photocatalytic degradation of dibenzothiophene (DBT) in $TiO_2$ aqueous suspension has been studied. $TiO_2$ photocatalysts are prepared by a sol-gel method. The dominant anatase-structure on $TiO_2$ particles is observed after calcining the $TiO_2$ gel at $500^{\circ}C$ for 1hr. Photocatalysts with various transition metals (Nd, Pd and Pt) loading are tested to evaluate the effect of transition metal impurities on photodegradation. The photodegradation efficiencies with $TiO_2$ including Pt and Pd are higher than pure $TiO_2$ powder. Also we investigated the applicability of $H_2O_2$ to increase the efficiency of the $TiO_2$ photocatalytic degradation of dibenzothiophene. The degradation efficiency increases with increasing dosage of $H_2O_2$ in the range of 0.01M to 0.1M . The effect of pH is investigated; we obtained the maximum photodegradation efficiency at pH 5. In addition, the intermediate analysis found dihydroxyl -dibenzothiophene as a reaction intermediate of dibenzothiophene during the photodegradation.

• KSBB Journal
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• 제14권3호
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• pp.380-383
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• 1999

본 연구를 통하여 Rhodococcus erythropolis IGTS8은 배양증애 유기 황화합물인 dibenzothiophene을 2-hydroxybiphenyl로 탈황하며 이 과정에서 계면활성 물질을 분비함을 확인하였다. 생산된 계면활성제로 인하여 배지내의 탁도와 균체의 건조증량 사이에는 비례관계가 없음을 확인하였다. 인위적으로 Tween 80을 넣어준 결과 균체성장 속도, 즉 DBT 분해율은 증가되었으며 2%(v/v)이상의 Tween 80 농도에서는 오히려 저해 효과를 보았다.

• 환경생물
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• 제18권1호
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• pp.33-39
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• 2000

Gordona sp. MS6, desulfurizing petroleum, can convert dibenzothiophene (DBT) to 2-hydroxybiphenyl (2-HBP) and sulfate. In this study, the effect of DBT degradation product on DBT desulfurization activity was investigated. When $Na_2$SO$_4$ and DBT were simultaneously added in the medium sulfur sources, specific growth rate of strain MS6 was doubled compared to not adding $Na_2$SO$_4$. But, sulfate inhibited DBT desulfurization rate, furthermore, when 0.05 g/L $Na_2$SO$_4$ was supplied DBT desulfurization rate decreased down to 40%. When 2-HBP and its derivative, 2, 2'-dihydroxybiphenyl (DHBP) were not added, DBT desulfurization rate was 5.0 $\mu$mol L$^{-1}$ㆍh$^{-1}$. With the increase of 2-HBP and DHBP concentration, DBT desulfurization rate was decreased. No DBT desulfurization activity of Gordona sp. MS6 was observed when initial concentration was over 0.15 mM 2-HBP and 0.8 mM DHBP [Gordona sp., Desulfurization, Dibenzothiophene, 2-Hydroxybiphenyl, Sulfate].

• Journal of Microbiology and Biotechnology
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• 제13권5호
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• pp.647-650
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• 2003

In anhydrous organic solvents, the complexes formed between AOT (dodecylbenzene sulfuric acid sodium salt) and hemoproteins, such as hemoglobin, myoglobin, or cytochrome c, displayed remarkably higher activity than the hemoprotein powders to oxidize dibenzothiophene, a model compound of organic sulfurs contained in fossil fuels. In slightly hydrophobic organic solvents, such as ethyl acetate and butyl acetate, dibenzothiophene was completely oxidized catalytically by the cytochrome c-AOT complex with cumene hydroperoxide (${\alpha},{\alpha}-dimethylbenzyl$ hydroperoxide) as an oxidant. In highly hydrophobic organic solvents, such as decane and hexadecane, however, the activity of the cytochrome c-AOT complex decreased, presumably due to the aggregation of the hemoprotein-AOT complex in these solvents.

• 한국패류학회지
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• 제30권3호
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• pp.177-187
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• 2014

Mussels have been commonly used in bioassay for quality assessments of environment. Moreover, several standard protocols for the developmental bioassay of bivalves have been proposed. In this study, the EC50 of polycyclic aromatic hydrocarbons (PAHs) was determined using mussel, Mytilus galloprovincialis embryonic developmental bioassay. To determine the sensitivity of M. galloprovincialis, their fertilized eggs were exposed to five PAHs (2-metylnaphthalene, fluorene, dibenzothiophene, phenanthrene, pyrene). The EC50 of 2-metylnaphthalene, fluorene, dibenzothiophene, phenanthrene, and pyrene were 232, 273, 67.9, 43.2, and $33.1{\mu}g/L$, respectively. The overall sensitivity of M. galloprovincialis in the present developmental bioassay was similar to or more sensitive than that of other marine organisms commonly used in aquatic bioassays. The results of this study could be provide with fundamental data of setting standard for protection of marine life and or can use prediction the aquatic toxicity of PAHs.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2001년도 추계학술발표대회
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• pp.517-520
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• 2001

Fossil fuels such as coal and crude oil contain various organic sulfur compounds. Combustion of these fuels emit sulfur oxides which are considered as msjor air pollutants causing acid rain problem. Among various organic sulfur compounds, aromatic sulfur compounds of thiophenes which constitute major sulfur fractions of heavy oils are not easily removed by hydrodesulfurization. Many peroxidase and hemoproteins are known to oxidize dibenzothiophene (DBT) to dibenzothiophene-sulfoxide(DBT - sulfoxide) then dibenzothiophene- sulfone (DBT-sulfone). The oxidation of DBT by the immobilized hemoproteins in n-octane was increased significantly when the hemoproteins were deposited on celites of the particle size between 0.75 - 1.0 mm and a conventional substrates. such as t-butyl hydroperoxide and cumene hydroperoxide. In anhydrous organic solvents with log P values larger than 4.0 DBT was completely oxidized by cumene hydroperoxide catalyzed by cytochrome c deposited on celites.

• Journal of Microbiology and Biotechnology
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• 제1권1호
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• pp.1-5
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• 1991

Sulfate-reducing bacteria have been isolated from soil and their abilities to degrade dibenzothiophene (DBT) were compared with those of type cultures. Among the strains tested a soil isolate M6 showed the highest ability to degrade DBT. Isolate M6 was characterized as a mesophilic obligatory anaerobe. The morphology of the bacterium was vibrioid with the size of $0.4-0.7{\;}\mu\textrm{m}{\;}by{\;}1.0-1.5{\;}\mu\textrm{m}$. Gram reaction was negative and nonsporulating. Desulfoviridin is present. Lactate, pyruvate, ethanol and malate supported growth of the bacterium in the presence of sulfate. Sulfate, sulfite, thiosulfate and sulfur served as electron acceptors for growth. Hydrogenase was present. The mol% of guanine and cytosine of DNA was determined as 56%. The bacterium produced viscous material. From these results, the isolate M6 was identified as Desulfovibrio desulfuricans.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2000년도 추계학술발표대회 및 bio-venture fair
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• pp.540-543
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• 2000

본연구에서는 Rhodococcus rhodochrous IGTS8 균주를 사용하여 고농도의 유상에서 탈황효율을 높이기 위한 오일 함유비, pH, 영양물질의 영향을 조사하였다. 오일 함유비에 의한 영향은 유상이 30%이하일 경우 그리 크지 않았으며, pH 조절에 의해 50%, 영양물질의 강화에 의해 32%의 탈황효율이 증가했다. 강화배지에서 pH를 조절하며 배양한 결과, 기존의 배양에 비해 136% 탈황효율이 증가했다.