• Proceedings of the PSK Conference
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• 2003.04a
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• pp.141.3-142
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• 2003

The inverse relationship between dietary flavonoids consumption and cardiovascular diseases may be associated with the ability of flavonoids to attenuate LDL oxidation. Although flavonoids have been employed to prevent against LDL oxidation, their pro-oxidant effect also deserves an attention in respect to untoward property. (omitted)

• Bulletin of the Korean Chemical Society
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• v.31 no.8
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• pp.2299-2303
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• 2010

A new approach to the use of potassium peroxodisulphate as an oxidizing reagent is proposed and applied to the case of oxidative aromatization of 1, 4-dihydropyridines with cetyltrimethylammonium peroxodisulfate, a phase transfer oxidant. We demonstrate how it is possible to increase the reactivity of potassium peroxodisulphate in the presence of phase transfer catalyst. Dealkylation in case of 4-n-alkyl/n-alkenyl was not obtained.

• Journal of the Korean Chemical Society
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• v.18 no.6
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• pp.443-446
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• 1974

The regenerated lubricating oils for an internal combustion engine, obtained from the sulfuric acid and clay treatment, showed an improved thermal oxidation stability regardless of additives, especially anti-oxidant, originally presented in the oils. It is believed that such improvement is due to the formation of anti-oxidant materials, which is observed by the in crease of 25 % of aromatic compounds.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09b
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• pp.1071-1074
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• 2006

Fabrication and investigation of composite made of graphite, SiC, mullite and aluminum as the additive are the aim of this project. Aluminum acts as an anti-oxidant. SiC is a non-metallic anti-oxidant that increases composite strength. Different compositions with influent percents of aluminum have been selected to determine product specifications by XRD, SEM and STA methods. Results show that the composition of 40wt% graphite-20% SiC- 20% mullite-20% aluminum is a more robust and occurs at elevated temperatures than other graphite combustion composites.

• YAKHAK HOEJI
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• v.37 no.1
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• pp.95-99
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• 1993

Peroxidase activity of cytochrome P-450 was examined using N, N-dimethylaniline (NDA) as a substrate and cumene hydroperoxide (CHP) as an oxidant. The initial rates of the N-demethylation for varied concentrations of NDA (0.05-0.5 mM) by P-450 at different fixed concentrations of CHP (0.02-0.2 mM) were determined. The results suggest that P-450 proceeds its peroxidative reaction by the rapid equilibrium random bi bi mechanism to form a ternary complex with substrate and oxidant as an active intermediate.

• Proceedings of the PSK Conference
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• 2003.04a
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• pp.288.2-288.2
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• 2003

The anti-oxidant activities of the various fractions from the herbs of Artemisia apiacea were investigated. The n-hexane and n-butanol fractions were found to cause significant free radical scavenging effects on DPPH, their scavenging potencies as indicated in IC50 values, being 230.1 and 183.7 mg/$m\ell$, respectively. (omitted)

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.123.3-124
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• 2003

To investigate the relationship between structure and biological activity of phenylpropanoids, we measured effects of phenylpropanoids on anti-oxidant and whitening activity. In DPPH radical scavenging activity, caffeic acid analogues had anti-oxidant activity in a dose-dependent manner. Although phenylpropanoids did not inhibit purified tyrosinase activity, they significantly inhibited tyrosinase activity and melanin production in MSH-stimulated B16 melanoma cells. (omitted)

• Proceedings of the Korean Society of Toxicology Conference
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• 2002.05a
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• pp.89-89
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• 2002

It is well known that oxygen radicals induce neuronal cell damage by initiation of lipid peroxidation chain reaction. Recent work has been also demonstrated that enzymatically generated free radicals cause the release of glutamate and aspartate from cultured rat hippocampal slices.(omitted)

• The Korea Journal of Herbology
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• v.20 no.4
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• pp.1-10
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• 2005

Objectives : We investigated the anti-aging effect on skin with the extract of the needles of red pine, Pinus densiflora. Methods : We measured various effects related to skin such as the anti-oxidant effect, the protection against ultraviolet (UV) irradiation, the inhibition of reactive oxygen species (ROS) generation, the induction of heat shock protein 70 (HSP70), the reduction of matrix metalloproteinase-2 (MMP-2) synthesis and senescent cell. Results : The results were as follows : The extract of the needles of red pine (RP) had the potent anti-oxidant effect and the ROS scavenging effect. Also RP preserved the systemic anti-oxidant enzyme system (superoxide dismutase and catalase) from UVB irradiation. RP protected the cell membrane from the damages induced by UVB irradiation. RP induced HSP70, a mediator of resistance to UVB irradiation. RP reduced the synthesis of MMP-2 induced by UVB irradiation. And RP inhibited the amount of senescent-associated (SA) ${\beta}-galactosidase$ staining, as a marker of replicative senescence. Conclusions : The results of our study indicate that the extract of the needles of red pine, Pinus densiflora, has anti-aging effects on skin.

• Journal of the Korean Society of Clothing and Textiles
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• v.36 no.8
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• pp.875-884
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• 2012

Many Koreans have recently bleached their black hair to blond or a light color due to the influence of their favorite Korean idols. Bleaching effects were studied under various bleaching conditions, such as the concentration of oxidants, the ratio between bleach accelerant and oxidant, and treatment temperature and time. The degree of damage of bleached hair with the same color difference (${\Delta}E$) intervals was observed in SEM images, the retention of breaking load and the change of color after dyeing. The ratio between bleach accelerant and oxidant of 1:2.5 was an effective condition. $L^*$ values of the bleached hair treated with 9% oxidant increased to 90 min. At a treatment temperature of $30^{\circ}C$, $a^*$ values were maximum at 30 min and then decreased as time further increased; however, $b^*$ values of the bleached hair increased as the treatment time increased. At $45^{\circ}C$, both of $a^*$ and $b^*$ values showed a maximum at a specific time. Bleaching efficiency was influenced most by temperature, followed in order by time, and oxidant concentration. As the treatment time increased, $L^*$ values greatly increased with twice treatment; however, $a^*$ and $b^*$ values decreased. Bleached hair, which had a color difference of higher than 30, showed the scales were completely removed and the retention of the breaking load greatly decreased. Highly bleached hair showed a great decrease in $L^*$ values by dyeing; however, dyeing with bright colors was more indicative to the effect of bleaching.