• Proceedings of the Microbiological Society of Korea Conference
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• 2004.05a
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• pp.47-50
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• 2004

The defenses against free radical damage include specialized repair enzymes that correct oxidative damages in DNA, and detoxification systems such as superoxide dismutases. These defenses may be coordinated genetically as global responses. We hypothesized that the expression of the SOD and the DNA repair genes would inhibit DNA damage under oxidative stress. Therefore, the protection of E. coli mutants deficient in SOD and DNA repair genes $(sod^-\;xth^-\;and\;nfo^-)$ was demonstrated by transforming the mutant strain with a plasmid pYK9 which encoded Photobacterium leiognathi CuZnSOD and human AP endonuclease. The results show that survival rates were increased in $sod^+\;xth^-\;nfo^+$ cells compared to $sod^-\;xth^-\;ap^+,\;sod^-\;xth^-\;ap^-,\;and\;sod^+\;xth^-\;ap^-$ cells under oxidative stress generated from 0.1 mM Paraquat or 3 mM $H_2O_2$. The data suggested that, at least, SOD and DNA repair enzymes may have collaborate protection and repair of the damaged DNA. Additionally, both enzymes are required for protection against free radicals.

• Journal of the Korea Institute of Military Science and Technology
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• v.14 no.5
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• pp.920-931
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• 2011

Nerve agents are irreversible inhibitors of the cholinesterase enzyme. Exposure causes a progression of toxic signs, including hypersecretions, fasciculations, tremor, convulsions, respiratory distress, epileptiform seizures, brain injuries and death. A combined regimen of prophylaxis and therapy is the most effective medical countermeasure for dealing with the threat of nerve agent poisoning to military personnel. In this paper, the author investigated the updated technologies regarding various pre- and post-treatment drugs for nerve agents detoxification which are under development in several countries including Korea. Some characteristics of active ingredients in the formulations of drugs, their action mechanisms, and effectiveness were analyzed. Additionally, part of experimental data on the transdermal patch studied in ADD using beagle dogs was introduced.

• Biomedical Science Letters
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• v.7 no.2
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• pp.65-70
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• 2001

We have carried out PCR reactions to investigate if cytochrome P450 (P450) enzymes (1A1, 1A2, 2C8, 2E1 and 3A4), which are well hewn to be the key enzymes in detoxification process and/or synthesis of steroids in the liver, are expressed in the human brain, too. P450 1A1, 2C8 and 2E1 were expressed clearly. However, P450 1A2 and 3A4 were not detectable. Their expression levels in the human brain could be extremely low or they were not expressed at all. One base substitution at nucleotide 290 (A->G) was identified in P450 1A1. It is suspected to be an individual polymorphism. Our results should contribute to the better understanding of the role of cytochrome P450 enzymes in the human brain.

• Biomedical Science Letters
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• v.12 no.1
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• pp.49-52
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• 2006

To elucidate the effect of antioxidant complex containing $\beta-carotene$, vitamin E, vitamin C, Ginkgo Biloba leaf extract and selenium on oxygen :tree radical production and detoxification system, rats were fed normal diet and normal diet with antioxidant complex 0.1%, 0.3% and 0.5% for 3 weeks. Feed efficiency ratio, changes in body weight, weight gain and amounts of feces of rat are similar in four groups. Liver weight per body weight and hepatic lipid peroxide weight increased in 0.5% group. However, hepatic glutathione contents in all antioxidant complex added groups were significantly increased compare with normal control group. On the other hand, the activity of xanthine oxidase was a little increased due to the amounts of antioxidant complex. Superoxide dismutase and gutathione peroxidase activity of 0.1% antioxidant complex added group were increased about $10{\sim}20%$ in comparison to normal control group. These results suggest that the supplementation of antioxidant complex 0.1% to basal diet may reduce the hepatic damage caused by free radicals.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.9
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• pp.1250-1260
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• 2010

Mycotoxins are secondary metabolites produced by fungi. These toxins pose serious health concerns to animals as well as human beings. Biodegradation of these mycotoxins has been considered as one of the best strategies to decontaminate food and feedstuffs. Biodegradation employs the application of microbes or enzymes to contaminated food and feedstuffs. Ruminants are considered to be resistant to the adverse effects of mycotoxins presumably due to the biodegrading ability of rumen microbes compared to mono-gastric animals. Therefore, rumen microbial source or microbial enzyme could be a great asset in biological detoxification of mycotoxins. Isolation and characterization of pure culture of rumen microorganisms or isolation and cloning of genes encoding mycotoxin-degrading potential would prove to have overall beneficial impact in the food and feed industry.

• The Korean Journal of Malacology
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• v.32 no.2
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• pp.73-81
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• 2016

Heat shock proteins (HSPs), one of the most highly conserved groups of proteins characterized to date, play crucial roles in protecting cells against environmental stresses, such as heat shock, salinity and oxidative stress. The glutathione S-transferases (GST) have important role in detoxification of oxidative stress, environmental chemicals and environmental stress. GST mRNA expression have been used as biomarkers on environmental stress. The purpose of this study was to investigate the death rate and the gene expression of Hsp70 and GST during air exposure and starvation. Results showed that, the expression of Hsp70 mRNA was significantly changed in the experiment groups, such as air exposure and starvation. GST mRNA expression was significantly increased in the experimental group of starvation. These results suggest that Hsp70 and GST were played roles in biomarker gene on the air exposure and starvation.

• Journal of Ginseng Research
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• v.18 no.2
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• pp.118-121
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• 1994

Alcohol and acetaldehyde concentrations were measured in the blood and brain of rats which were treated with 20% alcohol (control group) or co-administered 20% alcohol with ginseng extract residue roasted (test group). There was no change in blood alcohol concentration between control and test group. However, the brain alcohol concentration was lowered in the test group which was treated for seven days. The concentration of aldehyde in the brain and blood was lowered in the test group. The activities of monoamine oxidase b in various regions of brain were recovered to normal group in the test groups. However, the Quantities of naloxone binding receptors were not changed by ginseng extract residue roasted.

• Journal of Korean Society on Water Environment
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• v.23 no.5
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• pp.659-664
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• 2007

The objective of this study is to evaluate the detoxification method for the endocrine disrupting chemicals by manganese oxide. Manganese coated sand and bisphenol-A (BPA) was used as the reactive medium and the contaminant. Results showed that manganese oxide effectively degrades BPA by oxidative coupling reaction. The nonlinear oxidative coupling reaction orders were obtained for BPA and oxide, respectively. The reaction rate of BPA decreased as initial BPA concentration increased, as oxide loading decreased and as pH increased. The higher ionic strength, the higher reaction rate was observed. Divalent cations were adsorbed on the oxide surfaces, resulting in the decreased degradation rate of BPA.

• Korean Journal of Medicinal Crop Science
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• v.10 no.4
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• pp.294-297
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• 2002

A gene coding for the GST of cotton (Gh-5) was cloned into Escherichia coli and experssed. The enzyme remained within the cytoplasm of E. coli. An 696 bp open reading frame was in the 988 base pair fragment of the recombinant plasmid pET-30b(+). The deduced protein sequence consists of 232 amino acids and has a molecular mass of 30235.58 Da. The cloned enzyme conjugated reduced glutathione and 1-chloro-2,4-dinitrobenzene (CDNB). Plant GST cDNA was expressed in microbe and produced polypeptide had function as an enzyme.

• BMB Reports
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• v.44 no.7
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• pp.423-434
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• 2011

A female hormone, estrogen, is linked to breast cancer incidence. Estrogens undergo phase I and II metabolism by which they are biotransformed into genotoxic catechol estrogen metabolites and conjugate metabolites are produced for excretion or accumulation. The molecular mechanisms underlying estrogen-mediated mammary carcinogenesis remain unclear. Cell proliferation through activation of estrogen receptor (ER) by its agonist ligands and is clearly considered as one of carcinogenic mechanisms. Recent studies have proposed that reactive oxygen species generated from estrogen or estrogen metabolites are attributed to genotoxic effects and signal transduction through influencing redox sensitive transcription factors resulting in cell transformation, cell cycle, migration, and invasion of the breast cancer. Conjuguation metabolic pathway is thought to protect cells from genotoxic and cytotoxic effects by catechol estrogen metabolites. However, methoxylated catechol estrogens have been shown to induce ER-mediated signaling pathways, implying that conjugation is not a simply detoxification pathway. Dual action of catechol estrogen metabolites in mammary carcinogenesis as the ER-signaling molecules and chemical carcinogen will be discussed in this review.