• Environmental Mutagens and Carcinogens
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• 제23권2호
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• pp.45-50
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• 2003

Biological activities of PAHs are not known although PAHs are considered as carcinogens. Recent industrial society has human widely exposed to PAHs (polynuclear aromatic hydrocarbons) that are comming from the incomplete combustion of organic material as wider spread environmental contaminants. Our laboratory have been studied the effect of PAHs in the human breast cancer MCF-7 cells. In this study, we examined the human breast cancer MCF-7 cells as a new system to evaluate bioactivity of PAHs. We have selected 13 PAHs to examine bioassay using CYP1A1-luciferase reporter gene expression system where CYP1A1 1.6 Kb 5flanking region DNA was cloned in front of luciferase reporter gene and this plasmid was transfected into MCF-7 cells transiently. This cells then used for the study to observe the effect of PAHs. We demonstrated that PAHs induced the CYP1A1 promoter, CYP1A1 mRNA and 7-ethoxyresolufin O-deethylase (EROD) activities in a concentration-dependant manner. None of PAHs that we have tested showed stronger stimulatory effect on CYP1 gene expression than TCDD. Benz(a)anthracene and benzo(b)fluoranthene were weak responders to CYP1A1 promoter activity stimulation, CYP1A1 mRNA and EROD induction in MCF-7 cells and these chemicals seemed to respond less either CYP1A1 mRNA or EROD than CYP1A1 promoter activity. Benzo(k)fluoranthene, chrysene, and dibenzo(a, h)anthracene showed strong response to CYP1A1 promoter activity stimulation, CYP1A1 mRNA increase and also EROD induction in MCF-7 cells. Results of dose response study suggested that two strong responding PAHs, such as benzo(k)fluoranthene and dibenzo(a, h)anthracene might be mediated through Aryl hydrocarbon receptors system in MCF-7 cells.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 한국항해항만학회 2016년도 춘계학술대회
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• pp.132-134
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• 2016

The Study mainly focused on bioremediation of 16 types PAHs and heavy metals in contaminated marine sediments at filed scale study using slow release biostimulant ball (BSB) was investigated. In our experiment, filed scale study ($1m{\times}1m$) was performed and the effect of BSB on PAHs and heavy metals were analysed. BSB size and distance were determined and optimum size and distance were 3cm and 5.5cm respectively. BSB containing nutrients of acetate, nitrate and sulphate which can enhance the activity of microorganism to increase degrading capacity of PAHs and enhance the heavy metals stabilization also to decrease bioavailability. PAHs containing 16 types of 2, 3, 4, 5 and 6 rings compound PAHs were found and to degrade upto 100% in 2, 3 rings, upto 90 to 94% in 4 and 5 rings and 6 ring compound was degrade up to 70%. For heavy metals stabilization percentage was increased using BSB sediment and exchangeable portion was decreased and residual portion was increased in all analysed heavy metals. BSB enhance the PAHs degradation and stabilization of heavy metals percentages. BSB is a promising method for remediation of PAHs and heavy metals in contaminated marine sediments.

• Environmental Mutagens and Carcinogens
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• 제24권4호
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• pp.198-205
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• 2004

Cytochrome P4501B1(CYP1B1) is known to be inducible by xenobiotic compounds such as policyclic aromatic hydrocarbon(PAH) and dioxins such as 2,3,7,8-tetrachloro-dibenzo-p-dioxin(TCDD). And these induction of CYP1B1 is also regulated by many categories of chemicals. In order to investigate the effects of several chemicals on CYP1B1 gene expression in Hepa-I and MCF-7 cells, 5' flanking DNA of human CYP1B1 was cloned into pGL3 basic vector containing luciferase gene, and then transfected into these cells. After treatment of chemicals, the luciferase activity was measured. CYP1B1 enzyme metabolize PAHs and estradiol. CYP1B1 metabolize estradiol to 4-hydrozyestradiol that is considered as carcinogenic metabolite. Recent industrialized industrialized society, human has been widely been exposed to widespread environmental contaminants such as PAHs(polycyclic aromatic hydrocarbon) that are originated from the imcomplete combustion of hydrocarbons. PAHs are known to be ligands of the AhR(aryl hydrocarbon receptor). Induction of cytochrome P4501B1(CYP1B1) in cell culture is widely used as a biomarker for PAHs. Therefore we have studied the effect of PAHs in the human breast cancer cells MCF-7 to evaluate bioactivity of PAHs. We have used the United State of America EPA selected 13 different PAHs, PAHs mixtures and extracts from environmental samples to evaluate the bioassay system. We examined effects of PAHs on the CYP1B1-luciferase reporter gene and CYP1B1 mRNA level. Benzo(k)fluoranthene and dibenzo(a, h)anthracene showed strong response to CYP1B1 promoter activity stimulation, and also CYP1B1 mRNAs increase in MCF-7 cells in a concentration-dependent manner. RT-PCR analysis indicated that PAHs significantly up-regulate the level of CYP1B1 mRNA. Some flavonoids such as genistein, daidzein, chrysin, naringenin and morin were also investigeted. These flavonoids decreased B(k)F infuced luciferase activity at low concentration. But, these flavonoids exhibited stimulatory effect at high concentration.

• Journal of the Korean Society of Food Science and Nutrition
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• 제42권1호
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• pp.134-138
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• 2013

Benzo[a]pyrene, a polycyclic aromatic hydrocarbon (PAH) whose metabolites are mutagenic and highly carcinogenic, is listed as a Group 1 carcinogen by the IARC. In this study, Arabica and Robusta green coffee beans were roasted under controlled conditions and the formation of benzo[a]pyrene during the roasting process was monitored. The concentration of benzo[a]pyrene in ground coffee and brewed coffee were determined by a HPLC-fluorescence detector. The limit of detection (LOD) and limit of quantitation (LOQ) of benzo(a)pyrene were 0.03 and $0.09{\mu}g/kg$, respectively. Benzo[a]pyrene was only detected in the dark roast of ground coffee, with a concentration ranging from $0.147{\sim}0.757{\mu}g/kg$. The content of benzo[a]pyrene in Ethiopia Mocha Harrar G4 is the highest ($0.757{\mu}g/kg$).

• Publications of The Korean Astronomical Society
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• 제32권1호
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• pp.97-99
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• 2017

Our understanding of dust emission, interaction, and evolution, is evolving. In recent years, electric dipole emission by spinning dust has been suggested to explain the anomalous microwave excess (AME), appearing between 10 and 90 Ghz. The observed frequencies suggest that spinning grains should be on the order of 10nm in size, hinting at polycyclic aromatic hydrocarbon molecules (PAHs). We present data from the AKARI/Infrared Camera (IRC) due to its high sensitivity to the PAH bands. By inspecting the IRC data for a few AME regions, we find a preliminary indication that regions well-fitted by a spinning-dust model have a higher $9{\mu}m$ than $18{\mu}m$ intensity vs. non-spinning-dust regions. Ongoing efforts to improve the analysis by using DustEM and including data from the AKARI Far Infrared Surveyor (FIS), IRAS, and Planck High Frequency Instrument (HFI) are described.

• Korean Journal of Microbiology
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• 제35권1호
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• pp.53-60
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• 1999

The biodegradation of recalcitrant polycyclic aromatic hydrocarbon, pyrene was investigated in microcosm simulating the beach sand and seawater. The natural biodegradation rates of pyrene were between 30-2,200 ng/g(ml)/day in beach sand and seawater when the pyrenc loading rates were 100- 1,000 ppm at 5-$20^{\circ}C$. The effects of the inoculum size, pyrene concentralion, incubation temperature and surfactant addition were investigated in fertilized (Inipol EAP 22) samples. Generally the biodegradation in beach sand was higher than that in seawater. A mixed inoculum (Pseudomonus, Acinetobacter, Moruxella) showed the 3,120 nglglday of biodegradation rate in beach sand with 200 ppm pyrene, which was 7.8 times higher than the natural biodegradation rate. The highest transformation rate, 4,860 ng/g/day was obtained in the bioaugmented beach sand (1,000 ppm pyrene). The glucose and surfactant addition to enhance the removal have negatively influenced on the biodegradation of pyrene. In case ol surfactants, CMC (critical micell concentration) might bc the control factor for the biodegradation.

• Korean Journal of Microbiology
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• 제43권2호
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• pp.83-90
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• 2007

Sphingomonas sp. KS 301, which was isolated from oil contaminated soil, was shown to have five different SODs (SODI, II, III, IV, V) which can be separated by DEAE-Sepharose chromatography, and SOD III was finally purified in this study by ammonium sulfate precipitation, DEAE-Sepharose chromatography, Superose 12 gel filtration and Uno-Q1 ion exchange chromatography. The molecular weight of SOD III was 23 kDa as determined by SDS-PAGE and the apparent molecular weight of the native enzyme was estimated to be approximately 71 kDa by Superose-12 gel filtration chromatography. These data suggest that the purified SOD consists of at least two subunits. The specific activity of the SOD III was higher than Mn type or Fe type SOD of Escherichia coli by 5 fold. To determine the type of SOD III, inhibitory effects of $NaN_{3},\;H_{2}O_{2},\;KCN$ were examined. 10 mM $NaN_{3}$ was able to inhibit 56% of the SOD III activity, which indicates that this SOD is Mn type. The optimum pH of the SOD III was 7.0 and the optimum temperature was $20^{\circ}C$. N-terminal amino acid sequence of purified SOD III was most similar to those of Psudomonase ovalis and Vibrio cholerae among bacteria.

• Korean Journal of Food Science and Technology
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• 제30권1호
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• pp.206-212
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• 1998

This study was undertaken to explore the applicability of glutathione S-transferase (GST) activity as a predictable indicator to monitor chemical pollution in shells and fishes utilized for food. There were some variations in the basal level of GST activity depending on species tested. Ark shells, Anadara satowi, showed the highest normal enzyme activity, followed by catfish and marine mussels, Mytilus coruscus. White clams, Meretrix lusoria, Israeli carp and catfish had lower activity. When A. satowi was exposed to 3-methyl-cholanthrene (3-MC), a prototypic polycyclic aromatic hydrocarbon for 1 week, GST activity decreased by about 30%. This reduction in GST activity induced by 3-MC did not recover until two weeks after the cessation of exposure. GST activity increased in response to 3-MC in most of the other species studied. The GST elevation in M. coruscus attained its maxinum of about 200% at the termination of 3-MC exposure maintaining this level up to 2 weeks, and declined gradually thereafter. 3-MC also induced GST activity in lsraeli carp in a similar fashion to M. coruscus. Phenobarbital induced GST activity both in M. coruscus and lsraeil carp. Other chemicals. such as clofibrate, butylated hydroxyanisole. hexachlorobenzene, and oxolinic acid did not change the enzyme activity significantly in most speciel. Phenol depressed GST activity only in lsraeli carp. These results suggest that the basal level of GST activity is somewhat variable and that the direction of change in response to chemicals seems to be related to its normal activity. The change in enzyme activity can be a preditable indicator of some environmental chemicals such as PAHs and phenol.

• Journal of Life Science
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• 제8권3호
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• pp.257-262
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• 1998

Benzo(a)pyrene(B(a)P), an extensively studied polycyclic aromatic hydrocarbon(PAH), is a common contaminant produced through the burning of fossil fuels, particularly coal, and from the exhaust products of internal combustion engines. It produces a wide range of toxicities, including carcinogenicity in experimental animals. B(a)P has been shown to suppress systemic immunity in experimental animals, which may contribute to the growth of the chemical-induced tumors. Using colorimetric MTT assay natural killer(NK) cell-mediated growth inhibition of tomor cell was measured in normal and B(a)P-exposed C57BL/6 mice. Non-adherent splenocytes of normal or B(a)P-exposed mice were cultured with Yac-1 cells at four different effector/target(E/T) cell ratios ranging from 200/1, 100/1, 50/1, and 25/1 in an assay volume of 0.1 ml. After the optical density of culture wells containing MTT solution was measured at a wavelength of 540 nm, the percentage of dead cells relative to the control target cell number was calculated. The NK activity of B(a)P-exposed mice was markedly lower than that of non-exposed mice group at all E/T ratios. These results indicated that suppression of NK cell activity may play a role in allowing for the growth of tumors.

• Clean Technology
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• 제16권3호
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• pp.198-205
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• 2010

Two sets of thermal reaction experiment for chlorinated hydrocarbons were performed using an isothermal tubular-flow reactor in order to investigate thermal decomposition, including product distribution of chlorinated hydrocarbons. The effects of $H_2$ or Ar as the reaction atmosphere on the thermal decomposition and product distribution for dichloromethane($CH_2Cl_2$) was examined. The experimental results showed that higher conversion of $CH_2Cl_2$ was obtained under $H_2$ atmosphere than under Ar atmosphere. This phenomenon indicates that reactive-gas $H_2$ reaction atmosphere was found to accelerate $CH_2Cl_2$ decomposition. The $H_2$ plays a key role in acceleration of $CH_2Cl_2$ decomposition and formation of dechlorinated light hydrocarbons, while reducing PAH and soot formation through hydrodechlorination process. It was also observed that $CH_3Cl,\;CH_4,\;C_2H_6,\;C_2H_4$ and HCl in $CH_2Cl_2/H_2$ reaction system were the major products with some minor products including chloroethylenes. The $CH_2Cl_2$/Ar reaction system gives poor carbon material balance above reaction temperature of $750^{\circ}C$. Chloroethylenes and soot were found to be the major products and small amounts of $CH_3Cl$ and $C_2H_2$ were formed above $750^{\circ}C$ in $CH_2Cl_2$/Ar. The thermal decomposition reactions of chloroform($CHCl_3$) with argon reaction atmosphere in the absence or the presence of $CH_4$ were carried out using the same tubular flow reactor. The slower $CH_3Cl$ decay occurred when $CH_4$ was added to $CH_3Cl$/Ar reaction system. This is because :$CCl_2$ diradicals that had been produced from $CHCl_3$ unimolecular dissociation reacted with $CH_4$. It appears that the added $CH_4$ worked as the :$CCl_2$ scavenger in the $CHCl_3$ decomposition process. The product distributions for $CHCl_3$ pyrolysis under argon bath gas were distinctly different for the two cases: one with $CH_4$ and the other without $CH_4$. The important pyrolytic reaction pathways to describe the important features of reagent decay and intermediate product distributions, based upon thermochemistry and kinetic principles, were proposed in this study.