• Proceedings of the Korean Society of Toxicology Conference
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• 2002.05a
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• pp.78-78
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• 2002

Microsomal epoxide hydrolase (mEH), an epoxide detoxifying enzyme and putative cell surface autoantigen, is inducible by xenobiotics and by certain pathophysiological conditions. The present study was designed to determine mEH expression in H4IIE cells during cell death initiated by sulfur amino acid deprivation (SAAD) and to identify the signaling pathway for the enzyme induction.(omitted)

• Biotechnology and Bioprocess Engineering:BBE
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• v.8 no.5
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• pp.306-308
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• 2003

Enantioselective hydrolysis for the production of chiral styrene oxide was investigated using the epoxide hydrolase activity of a newly isolated Rhodosporidium kratochvilovae SYU-08. The effects of reaction parameters - buffer type, pH, temperature, initial substrate concentrations, phenyl-1,2-ethanediol concentrations on hydrolysis rate, and enantioselectivity - were analyzed. Optically active (S)-styrene oxide with an enantiomeric excess higher than 99 % was obtained from its racemate. with a yield of 38 % (theoretically 50% maximum yield) from an initial concentration of 80 mM.

• Bulletin of the Korean Chemical Society
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• v.30 no.12
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• pp.2989-2992
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• 2009

An efficient synthetic route of novel 2′(${\alpha}$)-C-fluoro-2′(${\beta}$)-C-methyl carbocyclic nucleoside analogues is described. The key fluorinated intermediate 7 was prepared from the epoxide intermediate 5 via selective ring-opening of epoxide. Coupling of 7 with nucleosidic bases under the Mitsunobu reactions followed by deprotection afforded the target carbocyclic nucleoside analogues. The synthesized compounds were evaluated as inhibitors of the hepatitis C virus (HCV) in Huh-7 cell line in vitro.

• Bulletin of the Korean Chemical Society
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• v.33 no.6
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• pp.1945-1948
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• 2012

Rhodamine B (RhB) and rhodamine 6G (Rh6G) were employed as catalysts for the synthesis of cyclic carbonate from carbon dioxide and epoxide. It turned out that the catalytic activity of Rh6G was nearly 29 times higher than that of RhB at 1 atm pressure, $90^{\circ}C$. Furthermore, the catalytic efficiency of RhB and Rh6G was greatly enhanced with triethylamine as co-catalyst. Under the optimized conditions, the best isolated yield (93%) of cyclic carbonate was achieved without organic solvent and metal component.

• Proceedings of the Korean Society of Toxicology Conference
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• 2002.11b
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• pp.177-177
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• 2002

In order to investigate the association of genetic factor with asthma and contribution of the genetic interactions to the incidence of asthma in Korean population, the genetic polymorphisms of Epoxide Hydrolase(EH), CD14 and ${\beta}$2-adrenergic receptor genese(${\beta}$2AR) among 33 asthma patients and 66 controls were examined.(omitted)

• Korean Journal of Food Science and Technology
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• v.30 no.6
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• pp.1312-1320
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• 1998

Some commercial beef loins in raw state were packaged with PVDC as aerobic and vacuum condition. The other beef samples were cooked until core temperature arrived at $70^{\circ}C$ and then packaged immediately in the same way as the raw state. These samples were irradiated by electron beam (0, 1, 2 kGy), and then stored in refrigerator $(2{\sim}4^{\circ}C)$. Identity and quantity of cholesterol oxides were analysed at the 0, 7th, 14th day of storage. In the samples that were raw and packaged aerobically, $7{\alpha}-hydroxycholesterol,\;{\beta}-epoxide,\;7{\beta}-hydroxycholesterol$ and 7-ketocholesterol were detected over $0.5\;{\mu}g/g$. Cholestanetriol and${\alpha}-epoxide$ were detected at levels below $0.5\;{\mu}g/g$ during storage. In the samples that were raw and vacuum-packaged, $7{\alpha}-hydroxycholesterol$, 7-ketocholesterol and cholestanetriol were detected. In the samples that were cooked and packaged aerobically, cholestanetriol and ${\alpha}-epoxide$ were detected below $0.5\;{\mu}g/g$ during storage. $7{\alpha}-hydroxycholesterol,\;{\beta}-epoxide,\;7{\beta}-hydroxycholesterol$and 7-ketocholesterol were detected as $1.53{\sim}26.81,\;1.07{\sim}5.23,\;40.64{\sim}101.30\;and\;7.16{\sim}33.91\;{\mu}g/g$, respectively. In all results, total amounts of cholesterol oxide increased significantly as irradiation dose and storage time increased (P<0.05).

• The Korean Journal of Pharmacology
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• v.21 no.1
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• pp.1-11
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• 1985

The effects of feeding indole, indole-3-carbinol and benzofuran (all at 5 mmole/kg body wt./day) on various hepatic microsomal and cytosolic enzyme activities involved in xenobiotic metabolism have been compared. Benzofuran was found to elevate the activities of many enzymes both in microsomes (e.g., aniline hydroxylase, 7-ethoxycoumarin O-deethylase, p-nitrophenol UDPGA-transferase and epoxide hydrolase) and in cytosol (e.g., glutathione reductase, glutathione S-transferase, NADH:quinone reductase and UDP-glucose dehydrogenase). The structures of indole and indole-3-carbinol are similar to benzofuran except for the substitution of nitrogen with oxygen atom within the furan ring. Results showed that the activities of UDPGA-transferase and NADH:quinone reductase were not elevated by these indole compounds. While the chemical structure of these two indole compounds are identical except for the presence of the carbinol (methanol) group in indole-3-carbinol, there were marked differences in the types and activities of microsomal enzymes that were enhanced. Among the microsomal enzyme activities determined, indole elevated only the NADPH:cytochrome c reductase, while indole-3-carbinol increased several mixed function oxidase and particularly the epoxide hydrolase activities. Based on the chemical structures of tested compounds and the observed results, possible explanations for the mechanisms involved in elevating epoxide hydrolase activity by benzofuran and indole-3-carbinol are discussed.

• Korean Journal of Food Science and Technology
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• v.22 no.7
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• pp.767-773
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• 1990

The effect of storage conditions on the oxidative stability of cholesterol in butter was studied by quantifying cholesterol oxides by GC-MS. Experimental variables for storage conditions were packaging, storage temperature, light source, and storage period. No cholesterol oxides were detected from packaged butter under all storage conditions. When unpackaged butter was stored under ultraviolet light at ambient temperature, $7{\alpha}-hydroxycholesterol,\;7{\beta}-hydroxycholesterol$, cholesterol ${\beta}-epoxide$, cholesterol ${\alpha}-epoxide$, cholestane-triol were detected after 2, 4, 6 and 8 weeks of storage. The amounts of cholesterol oxide species produced were different depending on the storage periods. The amounts of each cholesterol oxides, $7{\alpha}-hydroxycholesterol,\;7{\beta}-hydroxycholesterol$, cholesterol ${\beta}-epoxide$, cholesterol ${\alpha}-epoxide$, and cholestane-triol, produced after 2 weeks of storage were 34.2, 14.0, 12.1, 1.30, and 0.50 ppm, respectively, and after 8 weeks of storage were 68.1, 29.1, 56,3, 8.50, and 4.00 ppm, respectively with trace amounts of 3,5-cholestadien-7-one. When fluorescent light was used instead of ultraviolet light with other conditions remained the same, the same species of cholesterol oxides were detected but with lesser amounts.

• Applied Biological Chemistry
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• v.19 no.2
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• pp.112-119
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• 1976

The appearance of organochlorine pesticide residues in water, mud and clam (Meretrix lusoria) samples from the lower basin of Seomjin River around the Kwangyang Bay was surveyed to obtain the following results. 1) The concentrations of pesticide residues in the water samples were found to be in the order of dieldrin> aldrin>${\alpha}-BHC$> ${\gamma}-BHC$> endrin> heptachlor> heptachlor epoxide and in the range of $0-48ng/{\ell}$. 2) The concentrations of pesticide residues in the mud samples were found to be in the order of aldrin> dieldrin>${\alpha}-BHC$> ${\gamma}-BHC$> heptachlor> heptachlor epoxide> endrin, ranging $0-10\;{\mu}g/kg$ (dry matter), and to be more in lower layer than in upper layer. 3) The concentrations of pesticide residues in the clam samples were found to be in the of order heptachlor> ${\gamma}-BHC$> ${\alpha}-BHC$> aldrin> heptachlor epoxide> dieldrin> endrin and in the range of $0.1-18\;{\mu}g/kg$ (edible fresh muscle). The level reached the highest in 3-year old clams and sharply deceased thereafter.

• 한국생물공학회:학술대회논문집
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• 2001.11a
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• pp.648-651
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• 2001

Kinetic resolution of various racemic aromatic epoxides by newly isolated Aspergillus niger LK has been investigated, and enantioselectivity of whole-cell biocatalyst was analyzed. The epoxide hydrolase (EHase) of A. niger LK was cloned using RT-PCR. The sequence homology was compared with that of other microbial EHase and the gene for EHase was characterized at molecular level.