• 대한예방의학회:학술대회논문집
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• 1998.10b
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• pp.291-292
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• 1998

• YAKHAK HOEJI
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• v.39 no.5
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• pp.528-534
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• 1995

This investigation was aimed at the study of the antidiabetic activity and effect on hepatic glutathione metabolism of polysaccharide from Trichosanthes kirilowii in hyperglycemic rats with aboxan (175 mg/Kg, i.p.). As the results, the polysaccharide inhibited the increase of blood glucose, triglyceride level and lactate dehydrogenase activity, but cholesterol not changed. And it increased protein bound-SH, nonprotein bound-SH, glutathione level and inhibited the decrease of glutathione S-transferase.

• BMB Reports
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• v.31 no.4
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• pp.399-404
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• 1998

In order to gain further insight on the relationship between structure and function of glutathione S-transferase (GST), the six active-site mutants, R13T, K44T, Q51A, Q64A, S65A, and D98A, of human GST P1-1 were expressed in Escherichia coli and purified to electrophoretic homogeneity by affinity chromatography on immobilized GSH. The active-site mutants showed marked differences in substrate specificity. The substitution of Gln51 with threonine resulted in a drastic decrease in the specific activities to <10% of the wild-type value. The substitution of Arg13 with threonine resulted in more decreased specific activity toward cumene hydroperoxide and in the $I_{50}$ values of S-(2,4-dinitrophenyl) glutathione and benanstatin A. These results suggest that the substitution of Arg13 with threonine changes the conformation of the active site to increase the affinity for the product or electrophilic substrate. Lys44 seems to be in the vicinity of the H-site of hGST P1-1 or may contribute to some extents to the electrophile binding.

• The Korean Journal of Pesticide Science
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• v.2 no.1
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• pp.97-103
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• 1998

Effects of safener fluxofenim was investigated for crop injury of acetanilide's upland herbicides and for enzyme activity of glutathione S-transferase (GST) in grain sorghum. Bioassay with etiolated grain sorghum [Sorghum bicolor (L.) Moench. cv. 'G522DR'] seedlings grown in agar containing metolachlor or alachlor showed that they are strong inhibitors on root growth of grain sorghum ($GI_{50}=4.5{\mu}M$ for metolachlor and $6.2{\mu}M$ for alachlor). The safener fluxofenim applied by seed soaking protected growth of grain sorghum from crop injury of metolachlor or alachlor at the concentrations of 1 to 10 ${\mu}M$. There was a significant increase in glutathione-herbicide conjugates in root tissues of fluxofenim-treated seedlings. Activities of $GST_{-metolachlor}$ and $GST_{-CDNB}$ were increased by 82% and 70%, respectively, in the cytosolic fraction of roots with fluxofenim treatment.

• Journal of Life Science
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• v.12 no.5
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• pp.549-554
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• 2002

Taraxacunf mongofieum Hand-Mass aqua-acupuncture solution (TMAS) was prepared and investigated og, the effect on initiation of carcinogenesis. The following effe.Is as a blocking agent were measured. .(a) Indu.ction of quinone reductase, (b) Induction of glutathione S-transferase activity (c) Increase of reduced glutathione. TMAS was potent inducer of quinone reductase in Hepa Iclc7 murine hepatoma cells. Clutathione S-transferase activity was increased with TMAS. In addition glutathione levels were increased about 1.6-fold with TMAS in cultured murine hepatoma Hepa Iclc7 cells.

• The Journal of Internal Korean Medicine
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• v.21 no.1
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• pp.108-115
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• 2000

Objective : To investigate the hepatoprotective effects of Gami-oryungsan on the liver damage induced by bromobenzene. Method : The development of fibrosis and acute liver injury was examined by the chemical analysis of AST, AL T, ${\gamma}$-GTP . and epoxide hydrolase glutathione S-transferase glutathione peroxidase enzyme activity, lipidoperoxide levels, glutathione levels were measured and oberved. Results : The increasing levels of lipidoperoxide was decreased proportionally according to dose of extract GO. Epoxide hydrolase glutathioneS-transferase glutathione peroxidase enzyme activity highly increased in GO pre-acupunctured group compared with the group treated with only bromobenzene. The increase of serum AST, AL T, ${\gamma}$-GTP enzyme activity of mice by bromobenzene was inhibited by the administration of GO. Lipidoperoxide levels in rat's liver decreased compared to the case of bromobenzene-treated group. The levels of Glutathione decreased by bromo benzene were increased highly in GO pre-acupunctured group. Conclusion : These results suggest that GO extract recovers the damage of liver due to bromobenzene intoxication by decreasing the lipid peroxidation AST AL T ${\gamma}$-GTP enzyme activity and increasing epoxide hydrolase glutathioneS-transferase glutathione peroxidase enzyme activity, glutathione levels.

• Bulletin of the Korean Chemical Society
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• v.28 no.5
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• pp.772-776
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• 2007

In order to study the role of residue in the active site of glutathione S-transferase (GST), Arg13 residue in human GST P1-1 was replaced with alanine, lysine and leucine by site-directed mutagenesis to obtain mutants R13A, R13K and R13L. These three mutant enzymes were expressed in Escherichia coli and purified to electrophoretic homogeneity by affinity chromatography on immobilized GSH. Mutation of Arg13 into Ala caused a substantial reduction of the specific activity by 10-fold. Km GSH, Km DCNB and Km EPNP values of R13A were approximately 2-3 fold larger than those of the wild type. Mutation of Arg13 into Ala also significantly affected I50 values of S-methyl-GSH that compete with GSH and ethacrynic acid, an electrophilic substrate-like compound. These results appeared that the substitution of Arg13 with Ala resulted in significant structural change of the active site. Mutation of Arg13 into Leu reduced the catalytic activity by approximately 2-fold, whereas substitution by Lys scarcely affected the activity, indicating the significance of a positively charged residue at position 13. Therefore, arginine 13 participates in catalytic activity as mainly involved in the construction of the proper electrostatic field and conformation of the active site in human GST P1-1.

• The Korean Journal of Food And Nutrition
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• v.28 no.5
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• pp.866-870
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• 2015

In this study, coffee waste was extracted with different solvents such as ethyl acetate, methylene chloride and methanol to investigate the total polyphenol contents, electron donating ability and the inhibitory effect on glutathione S-transferase. The total polyphenol contents were $3,060.61{\pm}357.12{\mu}g\;GAE/mL$ in ethyl acetate, $909.09{\pm}35.71{\mu}g\;GAE/mL$ in methylene chloride, and $1,602.27{\pm}30.36{\mu}g\;GAE/mL$ in methanol. The total polyphenol contents showed a significant difference (p<0.05) between the solvents. The electron donating ability was $80.20{\pm}1.45%$ for ethyl acetate, $81.94{\pm}0.45%$ for methylene chloride, and $85.14{\pm}1.53%$ for methanol. The electron donating abilities were significantly different (p<0.05) between the solvents. The inhibitory effect of the various extracts on glutathione S-transferase (% inhibition) was $92.12{\pm}0.56%$, $88.48{\pm}0245%$ with methylene chloride extract, and $90.85{\pm}0.14%$ with methanol extract. These too were significant different (p<0.05) between the solvents. The two portions of coffee waste extracts obtained from ethyl acetate and methanol showed meaningful results on the total polyphenol contents, and the inhibition effects on glutathione S-transferase. Therefore, they can be utilized to develop health care foods and can be applied as antioxidants for cosmeceuticals.

• BMB Reports
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• v.29 no.2
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• pp.111-115
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• 1996

A novel glutathione S-transferase from Pseudomonas sp. DJ77 was expressed in E. coli and purified by glutathione-affinity chromatography. The enzyme was composed of two identical subunits. The molecular size of the enzyme was 42 kDa by sephadex G-150 gel permeation chromatography and Mr of each subunit was 23 kDa by sodium dodecylsulfate-polyacrylamide gel electrophoresis. pI value of the enzyme was approximately 5.8 by isoelectric focusing. This enzyme showed the highest activity toward 1-chloro-2,4-dinitrobenzene as the electrophilic substrate. The relative activities toward p-nitrobenzyl chloride and 1,2-dichloro-4-nitrobenzene were 3.8% and 1.3% of the activity toward 1-chloro-2,4-dinitrobenzene, respectively. $K_m$ and $V_{max}$ values for 1-chloro-2,4-dinitrobenzene calculated by Lineweaver-Burk plot were 0.76 mM and $14.81\;{\mu}mol/min/mg$, respectively, and those for glutathione were 6.23 mM and $64.93\;{\mu}mol/min/mg$, respectively. The enzyme showed highest glutathione S-transferase activity at pH 8.0 and was stable between pH 6.0 and 9.0. The enzyme retained its activity up to $35^{\circ}C$ for 90 min but was unstable above $45^{\circ}C$.

• The Journal of the Korea Contents Association
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• v.17 no.10
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• pp.289-299
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• 2017

To verify the association between susceptibility to chronic myeloid leukemia (CML) and GSTM1, GSTT1 gene polymorphisms in Asian populations, 9 papers published until July 2017 were cited in a meta-analysis. The null present types of the GSTM1, GSTT1 gene were analyzed individually. The significant association was found between CML and GST polymorphism (GSTM1; OR=1.306, 95% CI=1.091-1.563, p=0.004, GSTT1; OR=1.987, 95% CI=1.438-2.746, p=0.000). In addition, there was association between CML and the null type of the combination GSTM1-GSTT1 polymorphisms (OR=4.191, 95% CI=2.833-6.201, p=0.000). Thus, genetic polymorphisms of the GSTM1, GSTT1 and combination GSTM1-GSTT1 polymorphism in Asian populations may be risk factors for CML.