• 한국미생물·생명공학회지
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• 제34권2호
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• pp.174-179
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• 2006

PCBs(polychlorinated biphenyl)는 난분해성 물질로써, 환경호르몬으로 분류된 유독한 화합물이다. 이런 유독한 화합물인 PCBs 화합물이 오염된 토양 및 수계를 회복하기 위해 PCBs의 모체인 biphenyl을 효과적으로 분해하는 미생물을 토양으로부터 분리 선별하여 S. yanoikuyae BK10 (AF406817)와 같이 분해능이 우수한 균주를 분리하였다. 분리된 S. yanoikuyae BK10의 특성을 조사하기 위하여 자연계의 토양 조건인 pH 5.0$\sim$8.0에서 99%이상의 높은 biphenyl 분해효율을 보였다. 또한, 온도를 달리하여 실험 한 결과, 10$\sim$50$^{\circ}C$의 범위에서 모두 70%이상의 높은 분해효율을 보여줌으로써 실제 biphenyl/PCBs로_오염된 토양에서 온도의 영향을 덜 받고 biphenyl을 효과적으로 분해 할 수 있을 것으로 생각된다. S. yanoikuyae BK10는 biphenyl이 500 $\mu$g/ml으로 처리된 mineral salt 배지에서 48시간동안 99% 이상의 biphenyl을 분해하는 높은 분해활성을 보이며, biphenyl을 mineralization 시키는 것으로 판단된다. 또한 biphenyl 분해효소 유도 실험결과는 기질을 biphenyl로 사용하여 증식한 균체가 다른 기질을 사용해서 증식한 균체보다 약 2배가량 biphenyl을 빨리 분해시켰다. 그렇지만, cell-mass를 많이 얻을 수 있는 당을 탄소원으로 사용하여 배양하였을 때에도 단시간 내에 biphenyl분해 효소를 분비하여 biphenyl을 분해하는 것으로 보아, S. yanoikuyae BK10는 실제 biphenyl/PCBs에 오염된 토양 적용 할 경우 안정적으로 균주의 제공이 가능하다고 판단된다. 이상의 결과를 토대로, 토양에서부터 분리한 S. yanoikuyae BK10는 자연계에서 유해화합물인 biphenyl/PCBs을 효과적으로 분해 할 수 있다고 생각되며, 분리균주인 S. yanoikuyae BK10의 분자 생물학적 특성을 조사하여 biphenyl과 PCBs를 분해하는 유전자 탐색에 유용한 정보를 얻을 수 있을 것으로 사료된다.

• Journal of Microbiology
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• 제35권2호
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• pp.141-148
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• 1997

Alcaligenes xylosoxydans strain SMN3 capable of utilizing biphenyl grew not only on phenol, and benzoate, but also on salicylate. Catabolisms of biphenyl and salicylate appear to be interrelated since benzoate is a common metabolic intermediate of these compounds. Enzyme levels in the excatechol 2. 3-dioxygenas which is meta-cleavage enzyme of catechol, but did not induce catechol 1, 2-dioxygenase. All the oxidative enzymes of biphenyl and 2, 3,-dihydroxybiphenyl (23DHBP) were induced when the cells were grown on biphenyl and salicylate, respectively. Biphenyl and salicylate could be a good inducer in the oxidation of biphenyl and 2, 3-dihydroxybiphenyl. The two enzymes for the degradation of biphenyl and salicylate were induced after growth on either biphenyl or salicylate, suggesting the presence of a common regulatory element. However, benzoate could not induce the enzymes responsible for the oxidation of these compounds. Biphenyl and salicylate were good inducers for indigo formation due to the activity of biphenyl dioxygenase. These results suggested that indole oxidation is a property of bacterial dioxygenase that form cis-dihydrodiols from aromatic hydrocarbon including biphenyl.

• 한국환경과학회지
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• 제19권11호
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• pp.1391-1396
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• 2010

Three biphenyl-degrading microorganisms were isolated from polluted soil samples in Sasang-gu, Busan. Among them, isolate DS-94 showing the strong degrading activity was selected. The morphological, physiological, and biochemical characteristics of DS-94 were investigated by API 20NE and other tests. This bacterium was identified as the genus Pseudomonas by 16S rDNA sequencing and designated as Pseudomonas sp. DS-94. The optimum temperature and pH for the growth of Pseudomonas sp. DS-94 were $25^{\circ}C$ and pH 7.0, respectively. This isolate could utilize biphenyl as sole source of carbon and energy. Biphenyl-degrading efficiency of this isolate was measured by HPLC analysis. As a result of biological biphenyl-degradation at high biphenyl concentration (500 mg/L), biphenyl-removal efficiency by this isolate was 73.5% for 7 days.

• Journal of Microbiology and Biotechnology
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• 제8권3호
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• pp.264-269
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• 1998

Commamonas acidovorans SMN4 showed wide growth substrate spectra for various aromatic hydrocarbons. Strain SMN4 was able to grow on biphenyl producing a meta-cleavage compound, yellow 2-hydroxy-6-oxophenylhexa-2,4-dienoic acid with a spray of 2,3-dihydroxybiphenyl, while it also grew on catechol, developing yellow 2- hydroxymucoic semialdehyde with a spray of 100 mM catechol. Thus these results indicate that two-ring structures of biphenyl were cleaved by meta-mode in upper and lower pathways. Strain SMN4 metabolized various substituted biphenyl compounds and xylene to the corresponding benzoate derivatives through oxidation of the ring structures. It was clearly shown that biphenyl can be a common inducer in the oxidation of biphenyl and 2,3-dihydroxybiphenyl. Various compounds were examined for their suitability to serve as substrates for indole oxidation, indicating that biphenyl, benzoate, and succinate are quite good inducers of indigo production due to the activity of biphenyl dioxygenase. This results suggest that indigo formation is by means of the combined activities of biphenyl dioxygenase and tryptophanase.

• 폴리머
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• 제26권5호
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• pp.623-633
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• 2002

적인을 이용한 ortho-cresol novolac (OCN)과 biphenyl계 혼합 에폭시 수지 조성물의 열적 특성과 난연 특성을 검토하였다. OCN과 biphenyl 에폭시의 부피비에 따라 5가지 조성물을 디자인하였으며, TGA 및 DTG, 그리고 UL-94V 테스트를 통해 난연 효과를 평가하였다. 충전제와 적인의 함량이 증가할수록 열적 성질 및 우수한 난연 효과를 보였으나, 과량의 적인을 적용하였을 경우에는 열안정성의 저하를 유발하였다. 복합재료의 기저 수지호서 OCN/biphenyl 혼합 에폭시를 사용하였을 경우 OCN의 내열특성과 biphenyl 에폭시의 높은 발포 특성에 기인하여 보다 향상된 난연 특성을 확보할 수 있었다. 적인을 적용한 에폭시 수지 조성물의 난연 기구는 표면에서 형성된 발포성 탄화층 (char-layer)의 열적 방어 효과로 판단할 수 있었다.

• Environmental Analysis Health and Toxicology
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• 제1권1호
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• pp.61-70
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• 1986

The effect of polychlorinated biphenyls (PCB), phenol and biphenyl on the body, liver and kidney weights, and the activity of $\delta$-aminolevulinic acid dehydratase (ALAD), and the contents of microsomal cytochrome P-450, and hematocrit, TBAvalue. PCB (200 mg/kg), phenol (200 mg/kg), biphenyl (200 mg/kg), and biphenyl (100 mg/kg) added phenol (100 mg/kg) was treated orally to Sprague-Dawley rats for 3 days. In all treated groups, the body weights were decreased, while the weights of liver and kidney were increased in comparison with that of control group. The activity of $\delta$-ALAD was increased and hematocrit was decreased in PCB treated group, on the contrary biphenyl treated group was appeared opposite direction. The contents of microsomal cytochrome P-450 and concentration of protein were increased in all treated group. In biphenyl treated group and phenol treated group, TBA value was increased in both groups.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 하계학술대회 논문집
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• pp.707-710
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• 2000

Optimization of the biphenyl chloromethylation process with para-formaldehyde has been investigated in the presence of ZnCl$_2$with HCI gas by the Box-Wilson method of mathematical planning of experiment. The 4,4'- (dichloromethyl)-biphenyl yield dependence on the biphenyl para-formaldehyde ratio, temperature and reaction duration has been studied. A mathematical model of the process has been developed and optimal conditions for the biphenyl chloromethylation procedure has been determined.

• Journal of Microbiology
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• 제40권1호
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• pp.86-89
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• 2002

Rhodococcus sp. strain T104, which is able to grow on either biphenyl or limonene, was found to utilize phenol as sole carbon and energy sources. Furthermore, T104 was positively identified to possess three separate pathways for the degradation of limonene, phenol, and biphenyl. The fact that biphenyl and limonene induced almost the same amount of catechol 1,2-dioxygenase activity indicates that limonene can induce both upper and lower pathways for biphenyl degradation by T104.

• 한국대기환경학회지
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• 제2권2호
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• pp.51-59
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• 1986

Hydrodesulfurization of dibenzothiophene (DBT) dissolved in n-heptane was studied over sulfided $Ni - W/\gamma - Al_2O_3$ catalyst at temperature ranges from 513 to 573 K and at pressure ranges from 20 to 60 x $10^5$ Pa. Hydrogenation of biphenyl (BP) and cyclohexylbenzene (CHB) observed in products were also run. The products were almost biphenyl and cyclohyxylbenzene, and the conversion of DBT was very sensitive to temperature. Concerning the products distribution while the formation of biphenyl decreased, the formation of cyclohexylbenzene increased in the range of high pressure. The reaction network was found to be sequential reaction which formed cyclohexybenzent through the intermediate of biphenyl. The disappearances of DBT and biphenyl were the first order with respect to DBT and biphenyl and their activation energys were 24.3 and 13.6 Kcal/mol, respectively.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2005년도 총회 및 춘계학술발표회
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• pp.28-30
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• 2005

Because of high population diversity in soil microbial communities, it is difficult to accurately assess the capability of biodegradation of toxicant by microbes in soil and sediment. Identifying biodegradative microorganisms is an important step in designing and analyzing soil bioremediation. To remove non-important noise information, it is necessary to selectively enrich genomes of biodegradative microorganisms fromnon-biodegradative populations. For this purpose, a stable isotope probing (SIP) technique was applied in selectively harvesting the genomes of biphenyl-utilizing bacteria from soil microbial communities. Since many biphenyl-using microorganisms are responsible for aerobic PCB degradation In soil and sediments, biphenyl-utilizing bacteria were chosen as the target organisms. In soil microcosms, 13C-biphenyl was added as a selective carbon source for biphenyl users, According to $13C-CO_2$ analysis by GC-MS, 13C-biphenyl mineralization was detected after a 7-day of incubation. The heavy portion of DNA(13C-DNA) was separated from the light portion of DNA (12C-DNA) using equilibrium density gradient ultracentrifuge. Bacterial community structure in the 13C-DNAsample was analyzed by t-RFLP (terminal restriction fragment length polymorphism) method. The t-RFLP result demonstates that the use of SIP efficiently and selectively enriched the genomes of biphenyl degrading bacteria from non-degradative microbes. Furthermore, the bacterial diversity of biphenyl degrading populations was small enough for environmental genomes tools (metagenomics and DNA microarrays) to be used to detect functional (biphenyl degradation) genes from soil microbial communities, which may provide a significant progress in assessing microbial capability of PCB bioremediation in soil and groundwater.