• Proceedings of the Korean Society of Life Science Conference
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• 2002.09a
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• pp.50-50
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• 2002

• Radiation Oncology Journal
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• v.33 no.2
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• pp.66-74
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• 2015

Trace elements play crucial role in the maintenance of genome stability in the cells. Many endogenous defense enzymes are containing trace elements such as superoxide dismutase and metalloproteins. These enzymes are contributing in the detoxification of reactive oxidative species (ROS) induced by ionizing radiation in the cells. Zinc, copper, manganese, and selenium are main trace elements that have protective roles against radiation-induced DNA damages. Trace elements in the free salt forms have protective effect against cell toxicity induced by oxidative stress, metal-complex are more active in the attenuation of ROS particularly through superoxide dismutase mimetic activity. Manganese-complexes in protection of normal cell against radiation without any protective effect on cancer cells are more interesting compounds in this topic. The aim of this paper to review the role of trace elements in protection cells against genotoxicity and side effects induced by ionizing radiation.

• 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.

• Archives of Pharmacal Research
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• v.22 no.2
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• pp.99-107
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• 1999

A series of organosulfur compounds were synthesized with the aim of developing chemopreventive compounds active against hepatotoxicity and chemical carcinogesis. 2-(Allylthio) prazine (2-AP) was effective in inhibiting cytochrome P450 2E1-mediated catalytic activities and protein expression, and in inducing microsomal epoxide hydrolase and major glutathione S-transferases. 2-AP reduced the hepatotoxicity caused by toxicant sand elevated cellular GSH content. Development of skin tumors, pulmonary adenoma and aberrant crypt foci in colon by various chemical carcinogens was inhibited by 2-AP pretreatment. Anticarcinogenic effects of 2-AP at the stage of initiation of tumors were also observed in the aflatoxin B1 ($AFB_1$)-induced three-step medium-term hepatocarcinogenesis model. Reduction of $AFB_1$-DNA adduct by 2-AP appeared to result from the decreased formation of $AFB_1$-8,9-epoxide via suppression of cytochrome P450, while induction of GST 2-AP increases the excretion of glutathione-conjugated $AFB_1$ . 2-AP was a radioprotective agent effective against the lethal dose of total body irradiation and reduced radiation-induced injury in association with the elevation of detoxifying gene expression. 2-AP produces reactive oxygen species in vivo, which is not mediated with the thiol-dependent production of oxidants and that NF-KB activation is not involved in the induction of the detoxifying enzymes. the mechanism of chemoprotection by 2-AP may involve inhibition of the P450-mediated metabolic activation of chemical carcinogens and enhancement of electrophilic detoxification through induction of phase II detoxification enzymes which would facilitate the clearance of activated metabolites through conjugation reaction.

• Advances in Traditional Medicine
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• v.7 no.3
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• pp.311-320
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• 2007

The present study was designed to estimate the protective effect of (-) epigallocatechin gallate (EGCG) on ethanol-induced liver injury in rats. Chronic ethanol administration (6 g/kg/day ${\times}$ 60 days) caused liver damage that was manifested by the elevation of markers of liver dysfunction - aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, lactate dehydrogenase, bilirubin and ${\gamma}$-glutamyl transferase in plasma and reduction in liver glycogen. The activities of alcohol metabolizing enzymes such as alcohol dehydrogenase and aldehyde dehydrogenase were found to be altered in alcohol-treated group. Ethanol administration resulted in the induction of cytochrome p450 and cytochrome-$b_{5}$ activities and reduction of cytochrome-c reductase and glutathione-S-transferase, a phase II drug metabolizing enzyme. Further, ethanol reduced the viability of isolated hepatocytes (ex vivo) as assessed by trypan blue exclusion test and induced hepatocyte apoptosis as assessed by propidium iodide staining. Treatment of alcoholic rats with EGCG restored the levels of markers of liver injury and mitigated the alterations in alcohol metabolizing and drug metabolizing enzymes and cyt-c-reductase. Increased hepatocyte viability and reduced apoptotic nuclei were observed in alcohol + EGCG-treated rats. These findings suggest that EGCG acts as a hepatoprotective agent against alcoholic liver injury.

• KSBB Journal
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• v.29 no.1
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• pp.1-8
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• 2014

Tyrosinases catalyze the hydroxylation of monophenolic compounds and the conversion of o-diphenols to oquinones. The enzymes are mainly involved in the modification of tyrosine into L-3,4-dihydroxyphenyl-alanine (L-DOPA) and DOPA/DOPAquinone-drived intermolecular cross-linking, which play the key roles of pigmentation to the cells. It is ubiquitously distributed in microorganisms, plants, and animals all around the nature world. They are classified as copper- containing dioxygen activating enzymes; two copper ions are coordinated with six histidine residues in their active sites and they are distinguished as met-, deoxy-, and oxy-form depending on their oxidative states. Natural extraction and recombinant protein approaches have been tried to obtain practical amounts of the enzymes for industrial application. Tyrosinases have been widely applied to industrial and biomedical usages such as detoxification of waste water containing phenolic compounds, L-DOPA as a drug of Parkinson's disease, biomaterials preparation based on the cross-linking ability and biosensors for the detection of phenolic compounds. Therefore, this review reports the mechanism of tyrosinase, biochemical and structural features and potential applications in industrial field.

• Journal of Microbiology and Biotechnology
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• v.19 no.4
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• pp.409-415
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• 2009

Galactomyces geotrichum MTCC 1360 degraded the Scarlet RR(100 mg/l) dye within 18 h, under shaking conditions(150 rpm) in malt yeast medium. The optimum pH and the temperature for decolorization were pH 12 and $50^{\circ}C$, respectively. Enzymatic studies revealed an induction of the enzymes, including flavin reductase during the initial stage and lignin peroxidase after complete decolorization of the dye. Decolorization of the dye was induced by the addition of $CaCO_3$ to the medium. EDTA had an inhibitory effect on the dye decolorization along with the laccase activity. The metabolites formed after complete decolorization were analyzed by UV-VIS, HPLC, and FTIR. The GC/MS identification of 3 H quinazolin-4-one, 2-ethylamino-acetamide, 1-chloro-4-nitro-benzene, N-(4-chloro-phenyl)-hydroxylamine, and 4-chloro-pheny-lamine as the final metabolites corroborated with the degradation of Scarlet RR. The phytotoxicity study revealed the nontoxic nature of the final metabolites. A possible degradation pathway is suggested to understand the mechanism used by G. geotrichum and thereby aiding development of technologies for the application of this organism to the cleaning-up of aquatic and terrestrial environments.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.6
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• pp.946-950
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• 2004

Young radishes which were grown in the soil containing sulfur increased quinine reductase (QR) activity in Hepa 1clc cells and isothiocyanate-like compound analyzed by HPLC. QR inducing activity was maximum in young radishes grown with 1,818 g/㎥ sulfur and was decreased when the soil was neutralized with lime mortar in order to improve a recovery. These results have suggested that consumption of young radishes, especially grown in the presence of sulfur, would prevent from cancer incidence through inducing detoxification enzymes and could have therapeutic effects for chemoprevention.

• Korean Journal of Acupuncture
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• v.17 no.1
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• pp.11-17
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• 2000

Induction of phase II enzymes such as quinone reductase (QR) or glutathione S-transferase (GST) is considered a major mechanism of protection against initiation of carcingenesis. The induction of detoxification enzymes and glutathione were studied with Lonicerae Flos aqua-acupuncture solution (LFAS), Angelicae gigantis Radix aqua-acupuncture solution (AGRAS), and Gamdutang aqua-acupunture solution (GAS) in murine hepatoma cells grown in microtiter plate wells. LFAS, AGRAS and GAS were potent inducers of QR activity. LFAS was induced about 2.6-fold at concentration of $3{\times}$. AGRAS and GAS were also induced about 2.6-, 1.8-fold at concentration of $5{\times}$, respectively. In addition, GST activity was increased with LFAS, AGRAS, and GAS. GSH levels were increased about 2-fold with LFAS at concentration of $5{\times}$, 1.3-fold with AGRAS at concentration of $3{\times}$, and 1.2-fold with GAS at concentration of $5{\times}$. These results suggested that LFAS, AGRAS, and GAS may act as blocking agents against carcinogenesis by induction of phase II marker enzymes.

• Biomolecules & Therapeutics
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• v.26 no.2
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• pp.218-223
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• 2018

The liver is an essential organ for the detoxification of exogenous xenobiotics, drugs and toxic substances. The incidence rate of non-alcoholic liver injury increases due to dietary habit change and drug use increase. Our previous study demonstrated that Ecklonia stolonifera (ES) formulation has hepatoprotective effect against alcohol-induced liver injury in rat and tacrine-induced hepatotoxicity in HepG2 cells. This present study was designated to elucidate hepatoprotective effects of ES formulation against carbon tetrachloride ($CCl_4$)-induced liver injury in Sprague Dawley rat. Sixty rats were randomly divided into six groups. The rats were treated orally with ES formulation and silymarin (served as positive control, only 100 mg/kg/day) at a dose of 50, 100, or 200 mg/kg/day for 21 days. Seven days after treatment, liver injury was induced by intraperitoneal injection of $CCl_4$ (1.5 ml/kg, twice a week for 14 days). The administration of $CCl_4$ exhibited significant elevation of hepatic enzymes (like AST and ALT), and decrease of antioxidant related enzymes (superoxide dismutase, glutathione peroxidase and catalase) and glutathione. Then, it leaded to DNA damages (8-oxo-2'-deoxyguanosine) and lipid peroxidation (malondialdehyde). Administration of ES formulation inhibited imbalance of above factors compared to $CCl_4$ induced rat in a dose dependent manner. Real time PCR analysis indicates that CYP2E1 was upregulated in $CCl_4$ induced rat. However, increased gene expression was compromised by ES formulation treatment. These findings suggests that ES formulation could protect hepatotoxicity caused by $CCl_4$ via two pathways: elevation of antioxidant enzymes and normalization of CYP2E1 enzyme.