• 생약학회지
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• 제32권4호통권127호
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• pp.269-273
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• 2001

Ethanol extracts from Xanthii Fructus (XFE) and Prunellae Spica (PSE) were investigated for the effects on the induction of cancer chemoprevention-associated enzymes. The following effects were measured: (a) induction of quinone reductase (QR) (b) induction of glutathione S-transferase (GST) (c) reduced glutathione (GSH) level. XFE and PSE were potent inducers of quinone reductase activity in Hepa1c1c7 murine hepatoma cells. Glutathione levels were increased with XFE and PSE. In addition, glutathione S-transferase activity was increased with XFE. However, GST activity was not increased with PSE. These results suggest that XFE and PSE have chemopreventive potentials by inducing quinone reductase and increasing GSH levels.

• 생약학회지
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• 제32권2호통권125호
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• pp.168-174
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• 2001

Induction of phase II enzymes is a major mechanism of chemoprevention. The induction levels of quinone reductase (QR) activity in cultured murine hepatoma (Hepa 1c1c7) cells by 80%-methanol extracts of traditional medicinal plants were measured. Among the tested 81 plants, the extracts of Aralia continentalis, Magnolia obovata, and Viscum album were found to induce QR activities over 250%. The maximum induction levels obtained were 401.9%, 270.5%, and 301.8% by treatments of the extracts of A. continentalis $(318\;{\mu}g/ml)$, M. obovata $(53.8\;{\mu}g/ml)$ and V. album $(80.6\;{\mu}g/ml)$, respectively. These QR induction activities were more potent than those of the known QR inducers, t-butylhydroquinone (170.1%) and ${\beta}-naphthoflavone$ (320.0%).

• Natural Product Sciences
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• 제7권2호
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• pp.38-44
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• 2001

NAD(P)H:quinone reductase (QR), known as DT-diaphorase, is a kind of detoxifying phase II metabolic enzyme catalyzing hydroquinone formation by two electron reduction pathway from quinone type compounds, and thus facilitating excretion of quinoids from human body. With the usefulness of QR induction activity assay system for the modulation of toxicants, in the course of searching for cancer chemopreventive agents from natural products, the methanolic extracts of approximately two hundreds of oriental medicines were primarily evaluated using the induction potential of quinone reductase (QR) activity in cultured murine Hepa1c1c7 cells. As a result, several extracts including Hordeum vulgare, Momordica cochinchinensis, Strychnos ignatii, Houttuynia cordata, and Polygala japonica were found to significantly induce QR activity. In addition, the methylene chloride fraction of H. vulgare, one major dietary food source, showed potent induction of QR activity $(CD=6.4{\mu}g/ml)$. Further study for isolation of active principles from these lead extracts is warranted for the discovery of novel cancer chemopreventive agents.

• 한국식품과학회지
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• 제27권6호
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• pp.972-977
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• 1995

Quinone reductase(QR)를 포함한 2상효소계를 활성화시키는 성분들은 많은 동물실험에서 발암물질의 세포내 작용을 억제함으로서 항종양효과를 나타내는 것으로 보고되어 있다. 본 연구에서는 대표적인 농산부산물로서 미강, 밀기울, 탈지대두박, 두유박, 참깨박, 들깨박등 6종의 시료에 대한 암예방효과를 갖는 물질의 존재여부를 탐색하기 위하여, mouse hepatoma cell line(Hepalclc7 cells) 을 이용하여, quinone reductase활성유도 여부를 측정하였다. 참깨박과 들깨박의 80%메탄올 추출물은 0.5mg/ml 농도에서 강력한 QR 유도활성을 나타냈으며, 같은 농도에서 다른 시료들은 거의 QR 효소활성을 증가시키지 않았다. 한편 QR효소활성을 유도하는 성분을 찾아내기 위하여 일차적으로 TLC를 수행한 결과, 참깨박과 들깨박의 메탄올 추출물 가운데 사용한 전개용매(n-butanol : n-propanol : 2N ammonium hydroxide(10 : 60 : 30)에서 가장 빨리 이동하는 분획(Rf=0.70)이 유효성분을 함유하고 있음을 확인하였으며, 현재 활성성분의 동정이 진행중에 있다.

• Preventive Nutrition and Food Science
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• 제3권3호
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• pp.277-281
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• 1998

There is extensive evidence suggesting the protective role of fruits and vegetables against chemically induced carcinogenesis. We have tested the ability of a representative range of Korean vegetables to act as blocking agents against neoplastic initiation by determining the induction level of quinone reductase , an anticarcinogenci marker enzyme, in hepalclc 7 cells exposed to vegetable extracts. Among thirty vegetables tested, Arcitum lappa(Burdock), Brassica juncea (Mustard leaf), Pteridium aguilinum (Bracken) and Chrysanthemum cornoratium(Crown daisy) caused a significant induction of quinone teductase activity with a limited increase in arylhdrocarbon hydroxylase activity. Combination of crown daisy with burdock had synergistic effect on quinone reductase induction. Quinone reductase-inducing activity was found mostly in hesane and ehtylactate fractions of MeOH extract of crown daisy while it ws not quinone reductase activity in liver, kideny, lung, and small intestine, confirming the presence of potent QR inducer (s) in crown daisy. These sata suggest that some vegetables including crown daisy induced QR merits further investigation as a potential cancer preventive agent in human.

• 생명과학회지
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• 제10권1호
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• pp.79-85
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• 2000

Chemoprevention is one of the major strategies for cancer control. It is well established that dietary factors play an important role in modulating the development of certain types of human cancer. The experiment was conducted to determine quinone reductase(QR) activity induction of Daucus carota L. on HepG2 cells. Among various partition layers of roots of Daucus carota L., the ethyl acetate partition layer(DCMEA) and the n-hexane partition layer(DCMH) tested to be most effective which resulted 2.1 and 1.6 respectively compared to the control value of 1.0. In the case of seeds of Daucus carota L. n-butanol partition layer (DCMB) on HepG2 cells at a dose of 200 $\mu\textrm{g}$/$m\ell$ showed the highest induction activity of QR which was 3.0. These results suggest that potentially useful cancer chemoprevention chemicals could be isolated from DCMEA and DCMH of the roots and DCMB of the seeds of Daucus carota L.

• Archives of Pharmacal Research
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• 제24권6호
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• pp.597-600
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• 2001

Based on the potential cancer chemoprebentive activity of resveratrol, a trihydroxystilbene with the induction of quinone reductase activeity this study was designed to determine if stilbene-related compounds were inducers of phase ll detoxifying metabolic enzyme quinone reductase (QR) in the mouse hepatoma Hepa 1c1c7 cells. Among the thirteen compounds tested, several compounds including 3,4,5,3',5'-pentamethoxy-trans-stibene were found to potentially induce QR activity in this cell line. In addition, substitution with 3-thiofurane ring instead of phenyl ring in the stilbene skeleton also exhibited potential induction of QR activity. This result will give primary information to design the potential inducers of QR activity in the stilbene analogs.

• Natural Product Sciences
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• 제3권2호
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• pp.81-88
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• 1997

NAD(P)H:quinone reductase (QR) is one of the protective phase II enzymes against toxicity that accomplishes the capacity of detoxification by modulating the effects of mutagens and carcinogens. The detoxification mechanism is that quinone reductase promotes the 2-electron reduction of quinones to hydroquinones which are less reactive. This study is to search new inducers of quinone reductase from natural products, which can be used as cancer chemopreventive agents. Plant extracts were evaluated by using quinone reductase generating system With Hepa 1c1c7 murine hepatoma cell lines for enzyme inducing properties and crystal violet staining method for the measurement of cytotoxicity provoked. We have tested approximately 106 kinds of natural products after partition into n-hexane, ethyl acetate and aqueous layers from 100% methanol extracts of natural products. The ethyl acetate fractions of Vitex rotundifolia $(fruits,\;2FC:\;12.7\;{\mu}g/ml)$, Cnidium officinale $(aerial\;parts,\;2FC:\;10.5\;{\mu}g/ml)$, Chrysanthemum sinese $(flowers,\;2FC:\;17.4{\mu}g/ml)$ and the hexane fractions of Angelica gigas $(roots,\;2FC:\;13.2\;{\mu}g/ml)$, Smilax china $(roots,\;2FC:\;l1.9\;{\mu}g/ml)$, Sophora flavescens $(roots,\;2FC:\;16.3\;{\mu}g/ml)$ revealed the significant induction of quinone reductase in a murine hepatic Hepa 1c1c7 cell culture system.

• Preventive Nutrition and Food Science
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• 제4권2호
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• pp.122-124
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• 1999

Induction of NAD(P)H : (quinone-acceptor) oxidoreductase (QR) which obligatory two electron reduction of quinones and prevents their participation in oxidative cycling and thereby the depletion of intracellular glutathione, has been used as a marker for chemopreventive agents. We postulated that vitamin E, an antioxidant, which induces QR as the gene of QR was reported to contain antioxidant reponsive element in the 5'-flanking region. Vitamin E resulted in significant induction of QR in both hepalclc7 cells and mouse tissues. QR induction was observed; to be maximal at 25uM vitamin E for hepalclc7 cells while it was maximal in the level of 2.5∼5 μmoles vitamin E/㎏ BW for mouse tissues. Thus the cancer-preventive effect of vitamin E may be exerted by it induction of intracellular detoxifying enzymes.

• Korean Journal of Acupuncture
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• 제20권1호
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• pp.39-43
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• 2003

괴화약침액이 간세포의 quinone reductase, glutathione S-transferase 와 환원형 glutathione의 활성에 미치는 영향을 살펴 본 결과 괴화약침액은 암예방 효소인 Phase II enzyme을 유의성 있게 증가 시켰다. 따라서 괴화약침액은 암예방에 효과가 있는 것으로 사료된다.