• Korean Journal of Fisheries and Aquatic Sciences
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• v.22 no.6
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• pp.424-428
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• 1990

Mulletts, Mugil cephalus were exposed to artificial sea water containing $50{\mu}g/\iota\;of\;^{14}C-la-belled$ di-2-ethylhexyl phthalate(DEHP) during 15 days and returned to the DEHP free sea water in order to know bioconcentration and depuration of DEHP in the fish. Bioaccumulative process of DEHP in the fish was rather fast, and bioconcentration level of $9.7\~14{\mu}g/g$ and a bioconcentration factor of $220\~270$ were reached after one any of exposure. The biological half-life of DEHP in fish was 1.8 days. Five intermediate metabolites of DEHP were detected in the benzene and ethyl acetate fraction of fish by TLC.

• Journal of Nutrition and Health
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• v.36 no.4
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• pp.376-381
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• 2003

Acyl-CoA synthetase 4 (ACS4) is an arachidonate-preferring enzyme abundant in steroidogenic tissues. We examined ACS4 in rat liver, which contains a variety of pathways that use acyl-CoAs, in order to determine subcellular locations. We demonstrate that ACS4 protein was present most abundantly in the mitochondria and to a much lesser extent in the peroxisomes and microsomes. To determined the dietary effects on the level of ACS4 mRNA, northern blotting was carried out using total RNA from the livers of adult male rats fed various diets. Fasting, high fat diet, and fat-free high sucrose diet increased the hepatic level of ACS4 mRNA approximately 2-fold. Furthermore, the levels of ACS4 mRNA were induced by DEHP[Di- (2-ethylhexyl) phthalate]. These data suggest that ACS4 expression in the liver is regulated with a variety of pathways, including $\beta$-oxidation, hormone, and insulin.

• Korean Journal of Environmental Biology
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• v.25 no.4
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• pp.289-296
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• 2007

Di-(ethyhexyl) phthalate (DEHP), commonly used as a plasticizer for manufacturing flexible vinyl products, has been the topic of extensive research, especially concerning endocrine disrupting properties. Metallothionein (MT) is a low molecular weight (6,000$\sim$7,000 Da), cysteine-rich (22$\sim$23%), metal-binding protein and is known to be induced by extrinsic factors such as chemical agents and stresses. Some of the known function of MT include detoxification of heavy metals and alkylating agents and neutralization of free radicals. Nonetheless, the definitive physiological function of MT are still unknown. This study was carried out to investigate the effects of DEHP on the ultrastructural changes and the expression of MT of the rat liver. The rats were orally intubated with either corn oil (experimental control) or 0.5 mg, 1.5 mg and 4.5 mg DEHP kg$^{-1}$ day$^{-1}$ in 0.5 mL of corn oil for 15 days before sacrificing and sampling. DEHP induced mild ultrastrctural changes of some cell organelles such as rough endoplasmic reticulum, mitochondria, lysosomes and peroxisomes in the rat liver treated with DEHP. In the respect of immunogold labelling and Western blotting, MT expression of the liver tissue was up-regulated by DEHP. In conclusion, DEHP has effects on the ultrastructures and hepatic function for MT expression in rat.

• Journal of Korean Society of Environmental Engineers
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• v.32 no.5
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• pp.455-460
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• 2010

This study was carried out to find out any inherent problems occurring in the sampling and analytical procedures, and to suggest the relevant solutions to the problems. In addition, an optimal condition of clean-up process was developed, which was based on a method using silica glass column. As a result of experiments to test any artificial contamination of blank samples such as glassware and collection media, artifacts of DBP and DEHP appeared to be detected in various kinds of laboratory tools and apparatuses used in the sampling and analytical works. Therefore, it is necessary to investigate a degree of contamination before laboratory works by conducting a prior check any possible contaminations in all experimental tools and apparatus. It is also necessary to devise a method to avoid a tool, if possible, or to use a substitute of phthalate free. If the use of any plastic tool to cause contamination is inevitable, it should be properly corrected with a blank level, as is equally treated as the sample. The clean-up process demonstrated in this study can give us a significant benefit in terms of the quantity and quality of a target compound by GC/MS analysis.