• Journal of Life Science
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• v.15 no.3 s.70
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• pp.332-336
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• 2005

Epoxide hydrolase activities of various microbial cells were analyzed by colorimetric assay based on alkylation of epoxides with 4-(p-nitrobenzyl)pyridine (NBP). The epoxide hydrolase activity was determined by measuring the decrease of color intensity at 560 nm due to the decrease of styrene oxide substrate by epoxide hydrolase-catalyzed hydrolysis reaction. The experimental conditions of NBP colorimetric assay were optimized for the efficient measurement of epoxide hydrolase activities from various microbial cells.

• Journal of Life Science
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• v.13 no.2
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• pp.230-235
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• 2003

To investigate hepatoprotective activities of the root extract of Rosa davurica, the activities of hepatic enzymes, aminopyrine N-demethylase, aniline hydroxylase, glutathione S-transferase and epoxide hydrolase in rats intoxicated with bromobenzene were studied. Pretreatment with the methanol extract from the roots of Rosa davurica did not show any significant effects on the increases of the activities of aminopyrine N-demethylase and aniline hydroxylase, enzymes forming toxic epoxide by bromobenzene. There was no change in glutathione S-transferase activity by Rosa davurica. However, the activity of epoxide hydrolase, and epoxide-removing enzyme, was increased 33% by the administration of 500 mg/kg of the methanol extract. From the results, the protection of Rosa davurica against bromobenzene-induced hepatotoxicity is thought to be via enhancing the activity of epoxide hydrolase, an enzyme removing toxic epoxide rather than through epoxide-producing system.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2004.04a
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• pp.147-152
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• 2004

Aerobic cometabolism of cis-1,2-dichloroethylene (c-DCE) and c-DCE epoxide by a butane-grown mixed culture was evaluated. Transformation of c-DCE resulted in the concomitant generation of c-DCE epoxide. Chloride release studies showed nearly complete oxidative dechlorination of c-DCE (approximately 75%). Mass spectrometry confirmed tile presence of a compound with mass-to-charge-fragment ratios of 112, 83, 48, and 35. The values are in agreement with the spectra of a chemically synthesized c-DCE epoxide. Some evidences indicating the involvement of the monooxygenase in the transformation of c-DCE epoxide are: 1) $O_2$ requirement for c-DCE transformation and butane degradation; 2) butane inhibition on c-DCE transformation and vice versa; 3) the inactivation of c-DCE and c-DCE epoxide transformations by acetylene (a known monooxygenase inactivator); and 4) tire inhibition of c-DCE epoxide transformation by c-DCE.

• Proceedings of the Ginseng society Conference
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• 1988.08a
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• pp.39-42
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• 1988

We have studied the mechanism by examing the effect of ginseng on the epoxide hydrolase which is catabolized the reactive intermetabolite of bromobenzene. and bromobenzene-induced hepatotoxicity. It was observed that ginseng saponin fraction protects against bromobenzene-induced hepatotoxicity in mice as evidenced 1. increased the epoxide hydrolase activity. 2. lower serum transaminase activity. 3. decreased the formation of lipid peroxide. These results suggested that the inducing effect of ginseng on the epoxide hydrolase is believed to be a possible detoxication mechanism for the bromobenzene toxicity in mice.

• Archives of Pharmacal Research
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• v.12 no.1
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• pp.48-51
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• 1989

A new polyacetylene compound with cytotoxic activity against L1210 cells having diyne-ene and epoxy moiety, named panaxyne epoxide, was isolated from Panax ginseng C.A. Meyer. The chemical structure of the polyacetylene was determined to be tetradeca-13-ene-1,3-diyne-6,7-epoxide by UV, IR, $^1H-NMR,\;^{l3}$C-NMR and mass spectra.

• Journal of Life Science
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• v.15 no.1 s.68
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• pp.136-140
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• 2005

Microbial cell-based UV spectrometric assay for the quantitative measurement of epoxide hydrolase activity was evaluated and optimized for the efficient screening of whole cell activity of novel epoxide hydrolase. Epoxide hydrolase activity was determined by measuring the increase of the oxidized product, benzaldehyde. The effects of the concentrations of phenyl-1,2-ethanediol, sodium metaperiodate and cells were optimized for epoxide hydrolase-catalyzed hydrolysis of styrene oxide. The relevant kinetic parameters of Km and $V_{max}$ for the hydrolysis of (R)-styrene oxide by Rhodotorula glutinis were determined from Lineweaver-Burk plot as 41.2 nmol/min$\cdot$mg dcw and 7.5 mM respectively, and coincided well with those from GC analysis.

• YAKHAK HOEJI
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• v.56 no.1
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• pp.42-47
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• 2012

Soluble epoxide hydrolase (sEH) is a metabolic regulator of epoxyeicosatrienoic acids (EETs). EETs have many beneficial effects, vasodilation, anti-diabetes, anti-inflammation, cardiovascular protection, renal protection. Therefore, selective sEH inhibitors have a potential for treating these diseases. In the present study, screening methods for sEH inhibitors using PHOME ((3-phenyl-oxiranyl)-acetic acid cyano-(6-methoxynaphthalen-2-yl)-methyl ester) and 14-15-EET as substrates were established. To determine selectivity, microsomal epoxide hydrolase (mEH) inhibition assay was also developed using styrene oxide as a substrate of microsomal epoxide hydrolase. Our results obtained from 12-[[(tricyclo[3.3.1.13,7]dec-1-ylamino)carbonyl]amino]-dodecanoic acid (AUDA) used as a positive sEH inhibitor and valpromide used as a positive mEH inhibitor showed that these methods are useful for discovery of drug candidates.

• Journal of Institute of Control, Robotics and Systems
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• v.11 no.10
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• pp.857-863
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• 2005

A yeast strain utilizing styrene epoxide as a sole carbon and energy source was isolated from soil samples for the production of enantiopure of styrene epoxide by kinetic resolution. The strain, identified as a Rhodosporidium toruloides SJ-4, expressed an epoxide hydrolase which preferentially converted (R)-styrene epoxide into the corresponding diol. A maximum activity of 135 U/L was observed when biomass (dry cell mass) reached 6.7 g/L at 21 h of batch culture. Under the partially optimized reaction conditions ($35^{\circ}C$ and pH 8.0), the optically pure (S)-styrene epoxide was obtained with the yield of 21% when the initial substrate concentration was 100 mM. The reaction was completed at 9 h.

• Korean Journal of Pharmacognosy
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• v.25 no.1
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• pp.47-50
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• 1994

For the biological survey, effects of Ailanthi Cortex Radicis, the root bark of Ailanthus altissima(Simaroubaceae) on epoxide hydrolyzing enzymes were checked. The methanolic extract and its chloroform fraction were shown to activate the liver metabolizing enzyme system including epoxide hydrolase system which was monitored by activities of transaminase, lactate dehydrogenase, alkaline phosphatase and epoxide hydrolase system in bromobenzene treated rats. But they showed no effect on glutathione S-transferase activity.

• Journal of Life Science
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• v.12 no.5
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• pp.584-588
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• 2002

Asymmetric enantioselective resolution system using epoxide hydrolase activity of Aspergillus niger LK was developed and operated for the production of optically pure styrene oxide. Two-phase hollow-fiber reactor system was employed for the enhanced solubility of racemic styrene oxide in organic phase and protection of epoxide hydrolase activity in aqueous phase. For the removal of phenyl-1,2-ethandiol, the inhibitor of epoxide hydrolase, cascade hollow-fiber reactor system was also developed. Chiral (S)-styrene oxide (39 mM in dodecane) could be asymmetrically resolved with high enantiopurity (> 99% ee) using these reactor system.