• BMB Reports
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• v.32 no.2
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• pp.127-132
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• 1999

The NAD(P)H-quinone oxidoreductase (EC 1. 6. 99. 2) was purified from S. cerevisiae. The native molecular weight of the enzyme is approximately 111 kDa and is composed of five identical subunits with molecular weights of 22 kDa each. The optimum pH of the enzyme is pH 6.0 with 1,4-benzoquinone as a substrate. The apparent $k_m$ for 1,4-benzoquinone and 1,4- naphthoquinone are 1.3 mM and $14.3\;{\mu}M$, respectively. Its activity is greatly inhibited by $Cu^{2+}$ and $Hg^{2+}$ ions, nitrofurantoin, dicumarol, and Cibacron blue 3GA. The purified NAD(P)H-quinone oxidoreductase was found capable of reducing aromatic nitroso compounds as well as a variety of quinones, and can utilize either NADH or NADPH as a source of reducing equivalents. The nitroso reductase activity of the purified NAD(P)H-quinone oxidoreductase is strongly inhibited by dicumarol.

• Archives of Pharmacal Research
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• v.18 no.4
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• pp.256-261
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• 1995

The elevation of intracellular $Ca^{2+}$ in various tissue through oxidative stress induced by menadione has been well documented. Increase of $Ca^{2+}$ level inplatelets results in aggreaction of patelets. To test the hypothesis that menadione-induced $Ca^{2+}$ elevations can play a role in platelet aggregation, we have studied the effect of menadione on aggragation of platelets isolated from female rats. Treatment with menadione to platelet rich plasma (PRP), which proved to be 60% as determined by aggregometry. however, exposure of PRP to menadione leads to a loss of cell viability, as measured by lactae dehydrogenase (LDH) leakage, suggesting that menadione might induce cell lysis rather than aggregation of platelets. Turbidty changes induced by menadione were unaffected by addition ofl dicoumarol, which is a quinone reducellular factions of patelets. These data, which indicate an absence of the QR detoxifying pathway, suggest that platelets may be more susceptible to menadione-induced cytotoxicity than certain other cell, as hepatocytes.

• Journal of Microbiology and Biotechnology
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• v.11 no.6
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• pp.1071-1076
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• 2001

Chemopreventive activities of polysaccharides from soybeans fermented with either Phellinus igniarius or Agrocybe cylindracea were investigated by measuring the induction of quinone reductase (QR), glutathione S-transferase (GST) activities, and glutathione (GSH) levels in the cell culture along with inhibition of polyamine biosynthesis. The polysaccharides from soybeans fermented with P. igniarius strongly (p<0.005) induced QR activity at all concentrations tested. The extract not only induced GST activity in a dose-dependent manner in the concentration range of 0.1-1.0 mg, but significantly induced GSH revels in cultured Hepa 1c1c7 cells with a maximal 1.4-fold increase at 0.1 mg. The polysaccharides from soybeans fermented with A. cylindracea were effective in inhibiting polyamine metabolism. These results suggest that polysaccharides from soybeans fermented with P. igniarius or A. cylindracea have cancer chemopreventive activities in in vitro models and, therefore, could be considered as potential agents for cancer chemoprevention.

• Proceedings of the Korean Nutrition Society Conference
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• 2001.05a
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• pp.314.2-314
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• 2001

• Food Science and Biotechnology
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• v.16 no.4
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• pp.641-645
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• 2007

Delphinidin, an aglycone form of anthocyanins, was demonstrated to have anti-carcinogenic potential. The compound at $50\;{\mu}g/mL$ caused a significant increase of quinone reductase activity, an anti-carcinogenic marker enzyme, in mouse hepatoma cell lines (Hepa1c1c7 and BPRc1). Delphinidin enhanced the expression of other detoxifying or antioxidant enzymes including glutathione s-transferase, gamma-glutamylcysteine synthetase, heme oxygenase 1, and glutathione reductase. It suppressed the proliferation of murine hepatoma cells in a dose-dependent manner, with approximately $IC_{50}$ of $70\;{\mu}g/mL$. These results suggest that delphinidin might be useful for cancer prevention.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.2
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• pp.193-197
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• 1997

Elevation of the activities of phase 2 enzymes such as quinone reductase(QR) provides protection against several types of neoplasia. In this study, we performed partial purification of QR inducer(s) from roasted and defatted perilla meal by solvent fractionation and thin layer chromatography. Cellular QR induction was most notable in chloroform fraction of roasted perilla extract, compared with other solvent fractions. QR inducer(s) was partially purified by TLC, with 0.8 of $R_f$ value in n-butanol : n-propanol : 2N-ammonium hydroxide(10 : 60 : 30). AHH-inducing activity in TLC fractions isolated from methanol extracts of roasted perilla comigrated with QR-inducing fraction, suggesting that QR and AHH are induced by the same compound. TLC fractions shown strong QR-inducing activity also had a potent antioxidative activity, suggesting that cellular QR enzyme is induced by antioxidant(s) present in roasted perilla.

• Preventive Nutrition and Food Science
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• v.7 no.4
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• pp.358-366
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• 2002

To search for novel cancer preventive agents, we assessed the quinone reductase (QR)-inducing activities of medicinal herb extracts in cultured murine hepatoma cells (hepalclc7 cells). Among 216 herb extracts tested in this study, 8 kinds of herbal extracts were found to induce QR activity in hepalclc7 cells by more than 2-fold when used at the concentration of 25 $\mu\textrm{g}$/$m\ell$. The methanol extracts of Aster koraiensis NK and Pulsatilla koreana Nakai induced QR by 252 and 223 % , respectively, at the concentration of 25 $\mu\textrm{g}$/$m\ell$. Most of the herbal extracts with QR inducing-activity increased the enzyme activity in a typical dose-dependent manner. The QR activity in BP$^{r}$ cl cells was induced move than 50 % by the extracts of Pulsatilla koreana Nakai, Inula helenium, Physalis alkekengi var, francheti (Masters) Makino, Chrysanthemum zawadskii var. latilobum Kitamuva, Auemisia keiskeana Miquel, Chfsanthemum boreale Makino. In conclusion, hlsatilla koreana Nakai, Aster koraiensis N.K, and Chfsanthemum zawadskii var. iatilobum Kitamura, which showed relatively high QR induction, merit further animal study to evaluate their potential as cancer preventive agents.

• Fisheries and Aquatic Sciences
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• v.16 no.1
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• pp.1-5
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• 2013

To assess the feasibility of phlorotannins from Eisenia bicyclis as cancer chemopreventative agents, we tested whether they induced quinone reductase (QR) in Hepa1c1c7 cells. The ethyl acetate (EtOAc) soluble fraction obtained from E. bicyclis exhibited a QR induction activity in Hepa1c1c7 cells. Successive column chromatography of the active EtOAc fraction resulted in the isolation of four phlorotannins. Their structures were elucidated using one- and two-dimensional nuclear magnetic resonance spectroscopic techniques and characterized as phloroglucinol (1), dioxinodehydroeckol (2), dieckol (3), and fucofuroeckol-A (4). Among these compounds, fucofuroeckol-A (4) showed moderate QR induction activity, and dioxinodehydroeckol (2) exhibited potent QR induction potency with $2.05{\pm}0.04$ fold induction at a concentration of $50{\mu}M$ compared to the dimethyl sulfoxide solvent-treated control cells. However, phloroglucinol (1) and dieckol (3) exerted no detectable QR induction activity in Hepa1c1c7 cells. These results suggest that dioxinodehydroeckol could serve as a useful cancer chemopreventive chemical.

• Journal of Nutrition and Health
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• v.35 no.8
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• pp.880-885
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• 2002

This study was performed to determine the antimicrobial and anticarcinogenic activities of the Momordica charantia L. (MC) on several microorganisms and human cancer cell lines. In the paper disk test, its antimicrobial activity was increased in proportion to its concentration. Among the various solvent fractions of Momordica charantia L., the ethylether partition layer (MCMEE) showed the strongest antimicrobial activity. Also, the ethylacetate partition layer (MCMEA) and the butanol partition layer (MCMB) showed antimicrobial activity. We also determined the cytotoxicity and chemopreventive effect of Momordica charantia L. extract and fractions on human cancer cells. The experiment was conducted to determine the cytotoxicity of Momordica charantia L. partition layers on HepG2, HeLa and MCF-7 cells by MTT assay. Among the various partition layers of Momordica charantia L., MCMEE and MCMEA showed strong cytotoxic effects on all cancer cell lines. The chemopreventive effect of the quinone reductase induced activities of HepG2 cell, the hexane partition layer (MCMH) at a dose of 50 $\mu\textrm{g}$/mL was 3.62 times more effective compared with the control values of 1.0. Therefore, based on these studies, Momordica charantia L. may be developed into a potentially useful cancer chemopreventive agent.

• Journal of Life Science
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• v.14 no.4
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• pp.567-572
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• 2004

This study was carried out to investigate the affects on antimicrobial and cytotoxicity of red cabbage (Brassica oleracea L.,BO). In the paper disc test, antimicrobial activity of BO fractions was increased in proportion to its concentration. Among the various solvent fractions of methanol extract (BOM) of BO, the ethylacetate partition layer (BOMEA) showed the strongest antimicrobial activity We also determined the cytotoxicity and Quinone Reductase induced effect of BO extract and fractions on human cancer cells. The cytotoxicity of BO fractions on HepG2, HeLa and MCF-7 cells was evaluated by MTT assay. The BOMEE and BOMEA showed strong cytotoxic effects on all cancer cell lines we used. The quinone reductase induced effect of BO fractions on HepG2 cells, the hexane partition layer (BOMH) at a dose of 200 $\mu{g}$/ml was 2.88 times more effective compared to the control values of 1.0.