• Journal of Korean Society on Water Environment
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• v.22 no.6
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• pp.1123-1129
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• 2006

Pyrene of natural and anthropogenic sources is one of the toxic, mutagenic polycyclic aromatic hydrocarbons (PAHs) listed as priority pollutants. The objectives of this research are to break down pyrene by using ozonation, identify the intermediates and byproducts of pyrene, and test the biodegradability of intermediates and byproducts of pyrene in the aqueous phase. Since pyrene is non-polar, hexane was chosen as a solvent to effectively dissolve pyrene. Pyrene solutions were treated with ozone, as it has high oxidation capacity and electrophilic characteristic. After different ozonation pretreatment times (2, 3, and 10 minutes), intermediates of pyrene in the form of yellowish solid were collected from the hexane solution using a centrifuge. They were identified by gas chromatography/mass spectrometer (GC/MS). $BOD_5$, COD, and E-coli toxicity tests have been performed to assess the ozonation products.

• Journal of Environmental Science International
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• v.12 no.3
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• pp.337-344
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• 2003

The photodegradation of pyrene, chrysene and benzo［a］pyrene, that were similar in structure among poly-cyclic aromatic hydrocarbons (PAMs), were investigated in water irradiated with a low-pressure mercury lamp (wavelength of 253.7 nm and UV output of 1.35 ${\times}$ 10$\^$-3/J/s). The effects of several factors (t-BuOH, HCO$_3$$\^$-/ and pH) on photodegradation of above three PAHs were also examined. The photodegradation rates of PAHs decreased with increasing the concentration of t-BuOH, but decreased little with increasing the concentration of HCO$_3$$\^$-/ under the concentrations used in this study. The photodegradation rates of PAHs decreased with increasing pH, but their change were greater in case of pH increase from acid to neutral and were little in case of pH increase from neutral to base. The photodegradation rates of PAMs fitted a first-order kinetic model and their photodegradation rates decreased in the following sequences: pyrene>chrysene>benzo[a]pyrene among the PAHs used.

• Korean Journal of Microbiology
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• v.35 no.1
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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.

• Journal of Korea Soil Environment Society
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• v.3 no.2
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• pp.71-78
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• 1998

Pyrene is a common petroleum contaminant. This compound is recalcitrant to biological degradation and persists long in contaminated environments. A microcosm experiment was conducted to investigate the degradation rate of pyrene in three different of soil : rhizosphere soil ; non-rhizosphere soil ; and sterilized soil. The degradation rate followed the order of rhizosphere soil)non-rhizosphere soil)sterilized soil. And the rate did not change significantly when organic acids commonly found in the rhizosphere were added to each soil but it seemed to be well related to the increase of the number of microorganisms. Overall, it appears that pyrene is degraded faster in the rhizosphere soil which has the higher microorganism density.

• YAKHAK HOEJI
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• v.37 no.1
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• pp.18-29
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• 1993

This study was initiated to investigate the effective action and mechanism of GE-132 (Carboxyethylgermanium sesquioxide)on benzo(a)pyrene, which have strong carcinogenicity and mutagenicity. To confirm desmutagenic effect (inhibition of metabolic processes of benzo(a)pyrene with S9 Mix or inactivation of the mutagenicity of benzo(a)pyrene metabolites) and antimutagenic effect (inhibition of gene-expression of reverted genes) of GE-132 against benzo(a)pyrene using with Salmonella typhimuyium TA98 Ames test was performed. The revertants in desmutagenicity test were decreased significantly in the combined groups of benzo(a)pyrene and GE-132 than benzo(a)pyrene only, without inhibition the metabolism of benzo(a)pyrene by S9 Mix. The ideal combined groups of benzo(a)pyrene and GE-132 were 10 $\mu{M}$ and 10mg, 20 $\mu{M}$ and 20mg, 100 $\mu{M}$ and 30 mg, respectively. Then, the revertants in antimutagenicity test, which was studied the direct action of GE-132 on the induction of revertant cells by Salmonella typhimurium TA98 and activated benzo(a)pyrene were decreased significantly in the treated groups of GE-132 than no treated groups. The number of revertants of Salmonella typhimurium TA98 were reduced with increasing amounts of GE-132. From the above results, it was found that GE-132 inactivated the mutagenic metabolites of benzo(a)pyrene without inhibition of the enzyme action in the S9 Mix, and GE132 showed antimutagenic effect which have inhibitory action of reverted gene expression.

• Journal of Environmental Science International
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• v.12 no.7
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• pp.775-782
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• 2003

The photodegradations of pyrene, chrysene and benzo[a]pyrene that were similar in structure among polycyclic aromatic hydrocarbons (PAHs) were investigated with a low-pressure mercury lamp(the wavelength of 253.7 nm and UV output of 1.35${\times}$10$\^$-3/J/s). The optimum concentrations of TiO$_2$ and H$_2$O$_2$ on the photodegradation of pyrene, chrysene and benzo[a]pyrene were 1 g/L and 1.5${\times}$10$\^$-3/ M, respectively. By these optimum concentrations, their rates increased with increasing the concentration of TiO$_2$ and H$_2$O$_2$ because the amounts of OH radical formed increased, but for the higher concentrations than the optimum, their rates decreased with increasing those concentrations because the white turbidity phenomena occurs in case of TiO$_2$ and H$_2$O$_2$ acts as an OH radical inhibitor. The photodegradation rates among the photodegradation processes such as UV, UV/TiO$_2$, UV/H$_2$O$_2$, and UV/H$_2$O$_2$/TiO$_2$ decreased in the following sequences.: UV/H$_2$O$_2$/TiO$_2$> UV/H$_2$O$_2$> UV/TiO$_2$> UV.

• Textile Coloration and Finishing
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• v.26 no.4
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• pp.305-310
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• 2014

In this study, we presented a newly synthesized pyrene-naphthalene diimide(NDI)-pyrene triad. The optical and structural properties were examined using various characterization techniques. A donor-acceptor-donor triad molecule exhibited a strong charge transfer, though there existed neither intramolecular nor intermolecular hydrogen bonding sites, due to the formation of preferential complementary complex between pyrene and NDI. Powder XRD measurement revealed a sharp and distinctive X-ray patterns, indicating the presence of microcrystalline-like structure. POM images showed anisotropic fingerprint texture similar to that of cholesteric phase, and SEM images showed numerous columnar structures with length of 1 to $10{\mu}m$. Above observation clearly demonstrated that ${\pi}$-complementary NDI-pyrene interactions in the traid was strong enough to form columnar aggregates in the long range.

• Journal of Aquaculture
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• v.16 no.3
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• pp.196-201
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• 2003

Sessile organisms such as the oyster Crassostrea gigas have been given much attention as a potential biomonitoring indicator to assess the impact of toxicants on aquatic organism. In this study, we exposed cells isolated from gill of oyster (Crassostrea gigas) to hydrogen peroxide in vitro. In addition oysters were in vivo exposed to pyrene and benzo(a)pyrene at various concentrations for 2 weeks. Comet assay was used to detect DNA single strand breaks and to investigate the application of this technique as a tool for aquatic biomonitoring. Hydrogen peroxide increased DNA single strand break with increasing concentration after 30 minutes exposure in vitro. Pyrene and benzo(a)pyrene caused DNA damage only at very high concentration (100 $\mu\textrm{g}$/L or 1000 $\mu\textrm{g}$/L) at two week exposure in vivo. DNA damage was relatively higher at hemocyte than at gill. It suggested that metabolized PAHs are transferred to hemolymph from digestive gland which have a relatively high enzyme activity, and attacked the DNA of hemocyte, while gill accumulated PAHs without degrading them to their metabolites due to low enzyme activity at gill. Both in vitro and in vivo exposure experiments showed that the comet assay is an effective tool on screening whether the organism are exposed to genotoxic contaminants.

• Journal of Ginseng Research
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• v.16 no.3
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• pp.210-216
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• 1992

The effect of saponin extracted from Panax grneng CA Meyer on DNA repair and replicative DNA synthesis were examined in CHO-Kl cells cotreated with benzo(a)pyrene and rat liver S-15 fraction. The DNA strand breaks inititated by benzo(a)pyrene metabolites were measured by alkaline election technique. The addition of ginseng saponin to the culture media resulted in decrease of benzo(a)pyrene-induced DNA strand breaks, and restored the suppressed-semiconservative-DNA-synthesis by the carcinogen. DNA repair synthesis in the damaged cells was also elevated by the ginseng treatment when the repairing activites were measured for the (3H)-thymidine incorporation into the carcinogen damaged cellular DNk Comparative analysis of DNA-adduces of benzo(a)pyrene metabortes in microsomes suggested that ginseng saponin treatment in rats reduced the formation of electrophilic metabolites of benzo (a)-pyrene in the rat liver microsomes.

• Journal of Microbiology and Biotechnology
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• v.10 no.3
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• pp.344-348
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• 2000

Abstract The removal percentage (94%) of 100 ppm of pyrene in a shaken culture of white rot fungus, Irpex lacteus, was much higher than that in a static culture (37.9%). Over 90% of the pyrene disappeared with I. lacteus grown at $15-27^{\circ}C$, yet less than 50% was removed at $37^{\circ}C$. The transformation rates of pyrene ($4.5-5.0{\;}\mu\textrm{g}/ml/day$) were not very different among cultures with 5- 30% inoculum sizes, and over 90% of the 100 ppm pyrene was removed in every case during 20 days of incubation. The biodegradation of pyrene by I. lacteus was confirmed by measuring the $CO_2$ evolved from the mineralization of the added pyrene. The activity of lignin peroxidase (LiP), which is known to be involved in the biodegradation by white rot fungi, was high between 8 to 12 days of incubation. Although manganese peroxidase activity was demonstrated during the same period as LiP, its activity was quite low, and no laccase activity was detected. Even though the activity patterns of ligninolytic enzymes did not coincide with the pyrene removal, this study shows that I. lacteus has a high biodegrading capability and can be a candidate for the bioremediation of polycyclic aromatic hydrocarbon contaminants.inants.