• Journal of Microbiology and Biotechnology
• /
• 제12권3호
• /
• pp.417-422
• /
• 2002

Gene fusions were constructed by the transcriptional fusion of the dnaK promoter of pseudomonas sp. DJ-12 or E. coli to the lux or luc marker gene. The dnaKp-DJ::luxCDABE bioluminescent fusion in the biosensor using the Pseudomonas sp. DJ-12 dnaK promoter exhibited about 5-fold more extensive response to ethanol than that of dnaKp-EC::luxCDABE. The bioluminescent response of the dnaK-DJ::luc fusion to ethanol was much weaker than those of the other fusions. The biosensor harboring the dnaKp-DJ::luCDABE fusion was examined for its bioluminescence production based on exposure to aromatic compounds, such as biphenyl, 4-chlorobiphenyl (4CB), 4-hydroxybenzoate (4HBA), and catechol. In particular, the bioluminescence produced by the dnaKp-DJ::luxCDABE fusion was most sensitive to 1 mM biphenyl and 4CB when exposed for 80 min, and the responses were also very strong to other aromatics. Therefore, the biosensor bearing the dnaKp-DJ::luxCDABE fusion would appear to be the most useful for the detection of aromatics and other pollutants.

• 생명과학회지
• /
• 제21권1호
• /
• pp.159-164
• /
• 2011

미생물 세포 바이오센서는 환경오염물질의 모니터링을 위한 좋은 분석도구가 될 수 있다. 이는 리포터유전자들(예로, lux, gfp or lacZ)을 방향족 화합물이나 중금속과 같은 오염물질에 반응하는 유도 조절유전자와 결합하여 만든다. 이러한 유전자 재조합기술을 이용하여 많은 종류의 미생물 바이오센서가 개발되었으며 환경, 의학, 식품, 농업, 및 방위등 다양한 분야에서 활용되고 있다. 또한 바이오센서의 민감도와 검출범위는 조절유전자의 변형을 통해 증가시킬 수있다. 최근에는 미생물 바이오센서 세포를 고효율 검색용 세포 에레이의 칩, 광섬유 등에 고착하여 활용하고 있다. 본 논문은 특이 오염물질의 검출을 위한 유전자 재조합으로 만든 미생물 세포 바이오센서의 현황과 미래에 대해 고찰한다.

• 한국환경과학회지
• /
• 제14권6호
• /
• pp.597-603
• /
• 2005

In this study, we try to determine the distributive property in southwest coastal waters, such as K wang-yang bay, Ka-mak bay, Yeo-ja bay, Wan-do, Hea-nam, Young-gwang, and Mok-po, using simultaneous analytical method of 310 chemicals. The results were detected tens of the organic pollutants in sampling sites, and the major chemicals detected were CH type chemicals such as aliphatic, polycyclic compounds and were CHN(O) type chemicals such as aromatic amines, nitro compounds, In particular, pesticides were mainly detected in summer, phenols and phthalate esters were not seasonal effect. Also, a number of aromatic chemicals were detected in Kwang-yang bay, From the results of this study, we confirmed that it is mainly contaminated in summer and the pesticide chemicals are the major pollutants in southwest coastal waters.

• Biotechnology and Bioprocess Engineering:BBE
• /
• 제9권5호
• /
• pp.393-399
• /
• 2004

Useful genes can be Screened from various environments by construction of metagenomic DNA libraries. In this study, water samples were collected from several lakes in mid Korea, and analyzed by T-RFLP to examine diversities of the microbial communities. The crude DNAs r were extracted by the SDS-based freezing-thawing method, and then further purified using an $UltraClean^{TM}$ kit (MoBio, USA). The metagenomic libraries were constructed with the DNAs partially digested with EcoR I, BamH I, and Sac II in Escherichia coli DH 10B using the pBACe3.6 vector. About 44.0 Mb of metagenomic libraries were obtained with average inserts 13-15 kb in size. The bphC genes responsible for degradation of aromatic hydrocarbons via mets-cleavage were identified from the metagenomic libraries by colony hybridization using the bphC specific sequence as a probe. The 2,3-dihydroxybiphenyl (2, 3-DHBP) dioxygenase gene (bphC ), capable of degradation of 2,3-DHBP, was cloned and its nucleotide Sequences analyzed. The genes consisted of 966 and 897 base pairs with an ATG initiation codon and a TGA termination codon. The activity of the 2,3-DHBP dioxygenase was highly expressed to 2,3-DHBP and Showed a broad substrate range to 2,3-DHBP, catechol, 3-methylcatechol and 4-methylcatechol. These results in-dicated that the bphC gene identified from the metagenomes derived from lake water might be useful in the development of a potent strain for degradation of aromatic pollutants.

• 한국분무공학회지
• /
• 제20권2호
• /
• pp.121-129
• /
• 2015

This study was designed to investigate the emission characteristics of unregulated pollutants (Aldehyde, VOCs, PAHs) as well as regulated pollutants (CO, HC, NOx and PM) from diesel medium-duty trucks. The emission characteristics of unregulated and regulated pollutants were assessed based on regulation standards (EURO 4 and EURO 5) and intake weight (2.5 ton and 5 ton). The results show that unregulated and regulated pollutants remained almost unchanged at higher speeds but decreased at below 23.5 km/h. Reduction in unregulated and regulated pollutants was noticeable in vehicles of recent regulation standards and light intake weight. The analysis of aldehyde using UPLC showed that formaldehyde and acetaldehyde of aldehyde were most dominant. The GC/MS analysis showed that benzene, toluene, ethylbenzene and xylene of VOCs was over 80% followed by toluene, xylene, ethylbenzene and benzene. In addition, the analysis of PAHs using GC/TOF-MS indicated that bi- and tricyclic aromatic ring of aromatic compounds was 73% and 53% at 2.5 ton and 5 ton vehicles, respectively. The results of this study will be contributed to establish HAPs inventory.

• Carbon letters
• /
• 제12권3호
• /
• pp.152-161
• /
• 2011

Activated carbon was prepared from pre-carbonized petroleum coke. Textural properties were determined from studies of the adsorption of nitrogen at 77 K and the surface chemistry was obtained using the Fourier-transform infrared spectrometer technique and the Boehm titration process. The adsorption of three aromatic compounds, namely phenol (P), p-nitrophenol (PNP) and benzoic acid (BA) onto APC in aqueous solution was studied in a batch system with respect to contact time, pH, initial concentration of solutes and temperature. Active carbon APC obtained was found to possess a high surface area and a predominantly microporous structure; it also had an acidic surface character. The experimental data fitted the pseudo-second-order kinetic model well; also, the intraparticle diffusion was the only controlling process in determining the adsorption of the three pollutants investigated. The adsorption data fit well with the Langmuir and Freundlich models. The uptake of the three pollutants was found to be strongly dependent on the pH value and the temperature of the solution. Most of the experiments were conducted at pH 7; the $pH_{(PZC)}$ of the active carbon under study was 5.0; the surface of the active carbon was negatively charged. The thermodynamic parameters evaluated for APC revealed that the adsorption of P was spontaneous and exothermic in nature, while PNP and BA showed no-spontaneity of the adsorption process and that process was endothermic in nature.

• 해양환경안전학회:학술대회논문집
• /
• 해양환경안전학회 2004년도 춘계학술발표회
• /
• pp.85-88
• /
• 2004

본 연구에서는 서남해 연안 해역들인 광양만, 가막만, 여자만, 완도, 해남, 영광, 목포지역을 대상으로 다성분 일제분석법을 이용하여 서남해 연안에서의 유기오염물질 특성을 규명하였다. 그 결과 연안 해수에서 각 각 수십 종의 유기오염물질이 여름과 겨울철에 검출되었다. 특히 여름철에 Pesticide류에 의한 오염이 눈에 띄었으며 계절에 상관없이 Phenol류와 Phthalate류가 다종 검출됨을 알 수 있었고, 겨울철에는 광양만에서 다종의 Aromatic compounds가 나타났다. 이는 연안에서의 오염물질 유입, 선박들에서 기인한 오염원 유입, 항만이나 하구언 등에서 유입된 오염물질들로 인한 오염으로 사료된다.

• Ocean Science Journal
• /
• 제40권2호
• /
• pp.61-66
• /
• 2005

Benthic amphipod, Grandidierella japonica widely inhabits the Korean coastal waters and is developed as a standard test species for sediment toxicity tests. We exposed G. japonica to various pollutants including 4 kinds of inorganic metals (Ag, Cd, Cu and Hg), tributyltin [TBT], ammonia and 7 polycyclic aromatic hydrocarbon (PAH) compounds (acenaphthene, chrysene, fluoranthene, fluorene, naphthalene, phenanthrene and pyrene) to estimate the no observed effect concentration (NOEC) and the median lethal concentration (LC50) of each pollutant during the 96-hour acute exposure. Among all tested pollutants, TBT was most toxic to G. japonica, and Rg was most toxic among inorganic metals. The toxicity of pyrene to G. japonica was greatest among PAH compounds, followed by fluoranthene, phenanathrene, acenaphthene, fluorene and naphthalene. The toxicity of PAH compounds was closely related to their physico-chemical characteristics such as $K_ow$ and water solubility. G. japonica responded adequately to pollutant concentrations and exposure durations, and the sensitivity of G. japonica to various inorganic and organic pollutants was generally comparable to other amphipods used as standard test species in ecotoxicological studies, indicating this species can be applied in the assessment of environments polluted by various harmful substances.

• 한국미생물생명공학회:학술대회논문집
• /
• 한국미생물생명공학회 2000년도 추계 학술대회
• /
• pp.91-101
• /
• 2000

• Biotechnology and Bioprocess Engineering:BBE
• /
• 제5권6호
• /
• pp.422-430
• /
• 2000

Mechanism of lignin biodegradation caused by basidiomycetes and the history of lignin biodegradation studies were briefly reviewed. The important roles of fungal extracellular ligninolytic enzymes such as lignin and manganese peroxidases (LiP and MnP) were also summarized. These enzymes were unique in their catalytic mechanisms and substrate specificities. Either LiP or MnP system is capable of oxidizing a variety of aromatic substrates via a one-electron oxidation. Extracellular fungal system for aromatic degradation is non-specific, which recently attracts many people working a bioremediation field. On the other hand, an intracellular degradation system for aromatic compounds is rather specific in the fungal cell. Structurally similar compounds were prepared and metabolized, indicating that an intracellular degradation strategy consisted of the cellular systems for substrate recognition and metabolic response. It was assumed that lignin-degrading fungi might be needed to develop multiple metabolic pathways for a variety of aromatic compounds caused by the action of non-specific ligninolytic enzymes on lignin. Our recent results on chemical stress responsible factors analyzed using mRNA differential display techniques were also mentioned.