• Journal of Applied Biological Chemistry
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• v.42 no.1
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• pp.40-44
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• 1999

The in vitro antioxidative activities of the 33 plant-derived essential oils and 37 phytochemicals including 3 Mentha arvensis leaf-, 2 Thymus vulgaris leaf- and 2 Syzygium aromaticum flower-derived isolates were determined by the inhibition of linoleic acid autoxidation, the generation of superoxide anion and scavenging of DPPH radical. They were then compared to those of the widely used plant-derived antioxidants (pyrogallol and quercetin) and synthetic antioxidant BHT. At a concentration of 0.01%, potent antioxidative effect was observed in the essential oils from Cinnamomum cassia roots, Mentha arvensis leaves, Ginkgo biloba fruits, and Syzygium aromaticum flowers. Of the phytochemicals used, eugenol and isoeugenol at 0.01% showed potent antioxidative activity, and their activities were comparable to those of pyrogallol, quercetin, and BHT. The Cinnamomum root-, the Mentha leaf-, the Ginkgo fruit-, and the Syzygium flower-derived materials may be a good source for an alternative to the currently used antioxidants.

• Proceedings of the SCSK Conference
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• 2003.09a
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• pp.291-312
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• 2003

Reactive oxygen species are capable of damaging biomolecules such as lipids, proteins, and DNA, which can not only lead to various diseases, but also oxidative damage resulting aging. In our previous study, Cercis chinensis (Leguminosae) showed a potent antioxidant activity. Nineteen compounds were isolated through antioxidant activity-guided fractionation. The C. chinensis extract and some of the constituents exhibited a potent antioxidant activity on the free radicals and lipid peroxidation and a notable protective effect on the t-BuOOH induced oxidative damage. In vivo test of skin damage induced by UVB irradiation, the extract of C. chinensis and a constituent, piceatannol, exhibited a significant protective effect. The life-span of the HEK-N/F cells were extended by 1.21-2.12 fold as a result of the continuous administration of 3 $\mu\textrm{g}$/ml of the C. chinensis extract and the active constituents compared to that of the control. These observations were attributed to the inhibitory effect of the C. chinensis extract and its constituents on the age-dependent shortening of the telomere. Thus, C. chinensis was demonstrated to protect the skin cells against oxidative stress and inhibit thereby the cellular aging, followed by expectation as anti-aging cosmetic ingredient.

• Journal of Veterinary Clinics
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• v.21 no.3
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• pp.236-242
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• 2004

1,2-benzopyrone can stimulate macrophages to increase the ability of phagocytosis. Peripheral blood polymorphonuclear cells (PMN) and macrophages destroy microbial organisms with reactive oxygen species (ROS), called oxidative burst activity (OBA). This study was undertaken to determine whether 1,2-benzopyrone affects the OBA on the phagocytic response of canine peripheral blood phagocytes. The OBA of phagocytes in the addition or absence of latex beads was analyzed by flow cytometry system using dihydrorhodamine 123 (DHR). The direct treatments of 1,2-benzopyrone have no effect on the OBA of peripheral blood mononuclear cells (PBMC), PMN and monocyte-rich cells regardless of addition of latex beads. When latex beads are added to PMN, the OBA of PMN was remarkably enhanced by culture supernatant from PBMC but not PMN treated with 1,2-benzopyrone. Similary, it was also enhanced by human recombinant (hr) $TNF-\alpha.$ However, when latex beads were not added to PMN, its OBA was not enhanced by culture supernatant from either PBMC or PMN treated with 1,2-benzopyrone. The OBA of latex beads-phagocytized PBMC and monocyte-rich cells was not enhanced by culture supernatant from either PBMC or PMN treated with 1,2-benzopyrone. These results strongly suggested that 1,2-benzopyrone has an immunoenhancing effect on the OBA of PMN when phagocytic response occurred only. This enhanced OBA may be mediated through active humoral substance(s), such as $TNF-\alpha,$ produced by PBMC stimulated with 1,2-benzopyrone.

• Korean Journal of Plant Resources
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• v.23 no.6
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• pp.487-497
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• 2010

ROS have been associated with pathogenic processes including carcinogenesis through direct effect on DNA and play an important role in the pathogenesis of inflammation. Because of many types of phenolic acid derivatives and flavonoids, apples have been one of the human diet since ancient times and are one of the most commonly consumed fruits in worldwide. In this study, catechin, chlorogenic acid and phlorizin dihydrate were purified and identified by HPLC and GC/MS. The contents of catechin, chlorogenic acid and phlorizin dihydrate were 1.01 mg, 7.01 mg and 3.67 mg/ kg wet weight, respectively. Catechin and phlorizin dihydrate were found to significantly inhibit oxidative DNA damage, while chlorogenic did not affect. Also, catechin inhibits NO and $PGE_2$ production via suppressing iNOS and COX-2 expression. However, chlorogenic acid and phlorizin dihydrate did not affect. Our results show that catechin may be the most active phenolic compound in anti-oxidative damage and anti-inflammatory effect.

• Journal of Electrochemical Science and Technology
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• v.2 no.2
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• pp.85-90
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• 2011

Active oxygen species or free radicals are considered to cause extensive oxidative damage to biological macromolecules, which brings about a variety of diseases as well as aging. Electrolyzed reduced water(ERW) has been regarded as a ideal antioxidative agent in recent years. ERW is produced by passing a diluted salt solution through an electrolytic cell, within which the anode and cathode are separated by membrane. It can be produced reactive materials in ERW near the cathode during the electrolysis of water. ERW have the following advantages over other traditional cleaning agents: effective antioxidative agent, easy preparation, inexpensive, and environmentally friendly. The main advantage of ERW is its safety and antioxidative effect. ERW with strong reducing potential can be used to remove dirt and grease from items such as cutting boards and other kitchen utensils. The primary aim of this study is the activation mechanism of oxidation reduction potentials, ion conductivity, pH, and electrochemical properties with reactive materials in ERW.

• Electrical & Electronic Materials
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• v.8 no.3
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• pp.316-323
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• 1995

A vital step in magnetic tape manufacturing is the surface modification of polymer substrate prior to ink application. A critical element for good adhesion of magnetic ink on polymeric substrate is the ability to join ink in cost-effective manner. Corona discharging is one of the effective methods of modifying polymer surface to improve adhesion while maintaining the desirable properties of the film itself. Surface treatment by corona which is exposure of film surface to electron or ion bombardment, rather than mere exposure to active species, like atomic oxygen or ozone, can enhance adhesion by removing contaminant, electret, roughening surface, and/or introducing reactive chemical groups. Reactive neutrals, ions, electron and photons generated during the corona treatment interact simultaneously with polymers to alter surface chemical composition, wettability, and thus film adhesion. However, it is highly recommended that extensive chains scission be avoided because it can lead to side-effect by forming sticky matter, resulting in dropouts. This paper reviews principles of surface preparation of polymer substrate by corona discharging. In addition, the experimental section provides a description of parameter optimization on corona discharging treatment and its side-effect. Experimental results are discussed in terms of surface wetting as determined by contact angle measurements.

• BMB Reports
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• v.46 no.1
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• pp.59-64
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• 2013

Signal transducer and activator of transcription 3 (STAT3) and telomerase are considered attractive targets for anticancer therapy. The in vitro anticancer activity of the gold(I) compound auranofin was investigated using MDA-MB 231 human breast cancer cells, in which STAT3 is constitutively active. In cell culture, auranofin inhibited growth in a dose-dependent manner, and N-acetyl-L-cysteine (NAC), a scavenger of reactive oxygen species (ROS), markedly blocked the effect of auranofin. Incorporation of 5-bromo-2'-deoxyuridine into DNA and anchorage-independent cell growth on soft agar were decreased by auranofin treatment. STAT3 phosphorylation and telomerase activity were also attenuated in cells exposed to auranofin, but NAC pretreatment restored STAT3 phosphorylation and telomerase activity in these cells. These findings indicate that auranofin exerts in vitro antitumor effects in MDA-MB 231 cells and its activity involves inhibition of STAT3 and telomerase. Thus, auranofin shows potential as a novel anticancer drug that targets STAT3 and telomerase.

• Toxicological Research
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• v.18 no.3
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• pp.215-226
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• 2002

Acute or repeated physical exercise affects a large number of physiological parameters including hemodynamics, respiration, pH, temperature, gastrointestinal function and biotransformation, which determine the pharmacokinetics of drugs and chemicals. The rate and the amount of a chemical reaching the active site are altered by physical exercise, which results in significant changes in pharmacolosical/toxicological activity of the chemical. This aspect of physical exercise has vast implication in therapeutics and in safety evaluation, particularly for chemicals that have a low margin of safety. However there appears to be a wide inter- and intraindividual variation in the effects of physical exercise depend-ing on the duration, intensity and type of exercise, and also on the properties of each chemical. It is suggested that more studies need to be done to determine which factor(s) plays a major role in the disposition of chemicals in human/animals performing physical exercise. Certain chemicals induce severe toxicity due to metabolic conversion to reactive intermediate metabolites. it is suggested that repeated exercise may enhance the free radical scavenging system by increasing the activity of antioxidant enzymes. This area of research remain to be explored to elucidate the interaction of exercise and chemical on the antioxidant system.

• Natural Product Sciences
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• v.9 no.4
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• pp.226-231
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• 2003

Reactive oxygen species damage biomolecules such as lipids, proteins, sugars and DNA, which can not only lead to various disease but also oxidative damage resulting aging. In order to search for antioxidants from plants, the antioxidant effects of the MeOH extracts from 182 plants were evaluated. The results showed that thirteen plant extracts exhibited antioxidant activity (>80%) in DPPH radical assay, seven plant extracts demonstrated antioxidant activity (>40%) in the hydroxyl radical assay and eighteen plant extracts were active (>80%) in the lipid peroxidation assay. In particular, the extracts of Distylium racemosum (Hamamelidaceae), Astilbe koreana (Saxifragaceae), Astilbe chinensis and Euphorbia supina (Euphorbiaceae) were identified as potent principles of antioxidant activity in all the assay systems.

• Natural Product Sciences
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• v.18 no.1
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• pp.52-59
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• 2012

In our continuous efforts to procure the active materials from natural products in the protective effects of oxidative stress or UV damage to skin cells we found the Prunus persica flesh extract (PPFE) is considerable to meet the demand to protect the skin damage. PPFE attenuated cell damage induced by hypoxanthine-xanthine oxidase in cultured human keratinocytes, indicating that PPFE has the potential of the scavenging effect of reactive oxygen species (ROS) in human skin cell. Moreover, PPFE significantly suppressed UVA-induced ROS production determined by the oxidation of 2,7-dichlorodihydrofluorescein diacetate (DCFH) using FACS analysis. Additional study revealed that UVA irradiation of HaCaT human keratinocytes increased the gelatinolytic activities of matrix metalloproteinase-2, and -9 (MMP-2, -9) and mRNA expression of MMP-9 analyzing by a real-time reverse transcriptase-polymerase chain reaction (RT-PCR), and these events were significantly suppressed by the treatment with PPFE. These results suggest that PPFE might be applicable as natural ingredients for skin antiaging agents via UV-induced ROS scavenging activity and suppression of MMP expression in the skin cells.