• Journal of Nutrition and Health
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• v.27 no.5
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• pp.442-450
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• 1994

The purpose of this study was to determine the effects of 2-AAF injection time on hepatic lipid peroxide metabolism and cytochrome P450 content in Sprague-Dawley rats fed diets containing high amounts of vegetable oils or animal fats(15%, w/w). Fifty mg of 2-AAF/kg of body weight/day was injected in PEG 300 intraperitonially for 3 consecutive days after 4 or 8 weeks to rats fed corn oil(CO) or lard(LA) diet. The contents of lipid peroxide and cytochrome P450, and the activities of superoxide dismutase(SOD), glutathione peroxidase(GSH-peroxidase) and glutathione S-transferase(GSH-S-transferase) were determined in hepatic microsomal or cytosolic fraction. Microsomal thiobarbituric acid reactive substances(TBARS) and cytochrome P450 contents increased in Co group injected 2-AAF after 4weeks. Cytosolic SOD activity increased in CO group injected 2-AAF after 4 weeks and in LA group injected 2-AAF after 4 or 8 weeks. Cytosolic GSH-S-transferase activity increased in LA group compared to CO group without 2-AAF injection. GSH-S-transferase activity increased in CO group injected 2-AAF after 4 or 8 weeks and in LA group injected 2-AAF after 4 weeks. Therefore, it may be suggested that 2-AAF injection increase the contents of lipid peroxide or cytochrome P450, and detoxifying enzyme activities in rats fed CO diet for short period and in rats fed LA diet for longer period.

• Korean Journal of Pharmacognosy
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• v.34 no.2 s.133
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• pp.161-165
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• 2003

Ethanol extract from Thesium chinense Tunczaninov (TCTE) was tested for breast cancer chemopreventive activity by measuring 7,12-dimethylbenz[a]anthracene (DMBA) - induced cytochrome P450 1A1 activity, induction of quinone reductase and glutathione S-transferase, and glutathione level. TCTE significantly inhibited cytochrome P45O 1A1 activity at the concentration of 90 and 150 mg/ml. TCTE induced quinone reductase activity in a dose-dependent manner in a concentration range of 3-150 mg/ml. In addition glutathione S-transferase activity and glutathione level were increased with TCTE in cultured murine hepatoma Hepa1c1c7 cells. These results suggest that TCTE has breast cancer chemopreventive potential by inhibiting cytochrome P45O 1A1 activity, inducing quinone reductase and glutathione S-transferase activities, and increasing GSH level.

• Korean journal of applied entomology
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• v.43 no.4 s.137
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• pp.317-322
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• 2004

Insecticidal activity, systemic and residual effects, and effects on enzyme activities (esterase, acetylcholinesterase, glutathione S-transferase) of indoxcarb were evaluated against Plutella xylostella. The insecticide was very effective against larvae of P. xylostella. Also, indoxacarb showed only residual effect to P. xylostella when applied to vegetable leaves. It inhibited acetylcholinesterase activity, but didn't do esterase and glutathione S-transferase activities.

• Journal of Microbiology and Biotechnology
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• v.15 no.1
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• pp.183-187
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• 2005

Abstract The cancer chemopreventive potential of chitosanoligosaccharides was investigated by measuring the induction of quinone reductase and glutathione S-transferase activities and inhibition of cytochrome P450 1A1, 2B1, and 2E1 activities. Chitosanoligosaccharide I (1-${\kappa}$Da${\kappa}$Da) significantly induced glutathione S-transferase activity with a maximal 1.5-fold increase at 500 ${\mu}$g/ml, while chitosanoligosaccharide II (3-${\kappa}$Da${\kappa}$Da) (500 ${\mu}$g/ml) strongly induced quinone reductase (p<0.01) and glutathione S-transferase (p<0.005) activities. The in vitro incubation of rat liver microsomes with chitosanoligosaccharides I and II (2.5, 5, 50, and 500 ${\mu}$g/ml) showed a dose-dependent inhibiton of cytochrome P450 1A1, 2B1, and 2E1 activities. Chitosanoligosaccharide II was a more potent inhibitor of cytochrome P450 2B1 activity than chitosanoligosaccharide I. Accordingly, these findings suggest that chitosanoligosaccharides are potential chemopreventive agents.

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.5
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• pp.651-657
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• 1995

The antioxidative activity of each fraction in human milk was examined using H2O2 and FeSO4-induced lipid peroxidation of mouse liver homogenate in order to elucidate the antioxidative substances of human milk. High molecular weight(~>20KD) fraction had more antioxidative effect on lipid peroxidation than low molecular weight(~ <20KD) fraction. Furthermore, the changes of antioxidative enzyme activities were estimated during lactation to study the roles of human milk. The human milk showed high activities of catalase, glutathione(GSH) peroxidase and GSH S-transferase. These results suggest that the antioxidative activities may mostly be attributed to high molecular weight fraction containing catalase, GSH peroxidase and GSH S-transferase.

• Journal of Nutrition and Health
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• v.30 no.7
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• pp.803-812
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• 1997

The influences of dietary supplements of vitamin E on hepatocellular chemical carcinogenesis have been studied, Placental glutathione S-transferase(GST-P) positive foci area, antioxidant enzymes(superoxide dismutase(SOD), catalase, glutathione reductase, glutathione peroxidase, glutathione S-transferase(GST)), glucose 6-phosphatase(G6Pase) activities, and lipid peroxidation of mecrosomes(thiobarbituric acid reactive substances(TBARS) contents) were investigated. For is purpose , we used the murine chemical hepatocardinogenic procedure induced by modified Ito model, which consists of 200mg/kg body weight diethylinitrosamine (DEN) injection, 0.01% 2-acethlaminoflurene(2-AAF) feeding for 6 weeks, and partial hepatectomy on week 3. Weanling Sprague-Dawley male rats were fed pulverized Purina rat chow with 15, 000IU/kg diet vitamin E from initiation or promotion stages. We found that vitamin E supplement decreased the area of GST-P positive foci. Catalase, glutathione peroxidase, glutathione reductase. GST activities, and TBARS contents were decreased. On the other hand G6Pase activities were increased by vitamin E supplement. It seemed that vitamin E supplements helped endogenous defense systems against carcinogenesis by decreasing TBARS contents, $H_2O$$_2$ and organic peroxides. So, vitamin E seemed to protect cell from free radical damage in carcinogenesis. Anticarcinogenic effects of vitamin E were more effective at intiation that at promotion stage. These results suggest that vitamin E has suppressive effects on hepatocellular chemical carcinogenesis, probably through antioxidant effects against TBARS contents $H_2O$$_2$ and orgainc peroxides.

• Journal of Microbiology and Biotechnology
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• v.11 no.5
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• pp.870-875
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• 2001

A DNA fragment, pCKB13, containing two genes encoding Coenzyme a transferase, was isolated from a genomic DNA library of S. marcescens KCTC 2172. The complete nucleotide sequence of the 2,081-bp BamHI fragment on pCKB13 was determined. Sequencing of the fragment led to the identification of two open reading frames showing high homology with two Coenzyme A (CoA) transferases, Acetoacetyl-CoA transferase (Acot) and Succinyl-CoA transferase (Scot), enzymes catalyzing the reversible transfer of CoA from one carboxylic acid to another. The enzyme activity of Coenzyme A transferase increased after introducing the multicopy of the cloned gene in E. coli. The recombinant protein, overexpressed by multicopy and induction with IPTG, was a polypeptide of 42 kDa, as confirmed by SDS-PAGE. The protein was purified to homogeneity through three sequential chromatographic procedures including ion-exchanged DEAE-sepharose, CM-sepharose, and Mono Q.

• Journal of the Korean Society of Food Science and Nutrition
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• v.22 no.6
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• pp.702-708
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• 1993

The study was attempted to elucidate the mechanism of GE-132(100mg/kg, p.o. for 6 weeks) on the metabolism of bromobenzene (460mg/kg, i.p. bid, for 2 days), which has potent carcinogenicity, mutagenicity and hepatotoxicity. It showed that activities of cytochrome p-450, aminopyrine demethylase and aniline hydroxylase, which have epoxide generating property, were not changed by GE-132 treatment. On the other hand, epoxide hydrolase was not changed but that glutathione S-transferase was significantly increased by GE-132 treatment. And also ${\gamma}-glutamylcysteine$ synthetase was not changed following the GE-132 treatment, but the activity of glutathione reductase was significantly increased. The level of hepatic glutathione which was decreased by bromobenzene recovered markedly by GE-132 pretreatment. It is concluded that the mechanism for the observed effect of GE-132 on bromobenzene metabolism is due to the induction of glutathione S-transferase.

• BMB Reports
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• v.32 no.6
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• pp.535-540
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• 1999

Two types of the thioltransferase (also called glutaredoxin) have been previously detected in the cytosolic extract of Schizosaccharomyces pombe, a fission yeast. Previously, the one with a smaller molecular mass (14kDa) was purified and characterized. In the present study, the second thioltransferase was purified. The purification procedure included ammonium sulfate fractionation (40-80%), Sephadex G-200 gel filtration, DEAE-cellulose ion-exchange chromatography, Sephadex G-50 gel filtration, and glutathione-agarose affinity chromatography. The purified enzyme showed a single band on SDS-PAGE, and its molecular mass was determined to be 23 kDa. It utilizes various compounds as substrates, including 2-hydroxyethyl disulfide. Interestingly, we found that the purified thioltransferase also contains significant glutathione S-transferase activity.

• Korean Journal of Crystallography
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• v.14 no.1
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• pp.32-34
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• 2003

A helminth glutathione S-transferase. 28 kDa isozyme from Clonorchis sinensis has been crystallized under several conditions. One of the crystals, grown from a 10% polyehtylene glycol MME 550 (PEG MME 5 K) solution in 0.05 M potassium phosphate buffer (pH 7.0), diffracts to $3.0{\AA}$ resolution, and belongs to monoclinic space group C2, with unit cell parameters $a=95.83{\AA}$, $b=63.82{\AA}$, $c=235.09{\AA}$, and ${\beta}=97.2^{\circ}$.