• The Korean Journal of Food And Nutrition
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• v.12 no.4
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• pp.358-363
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• 1999

This study was conducted to evaluate the extraction methods for the determination of antioxidants in soybean oil. Recovery rates of various antioxidants in soybean oil showed similar rates as 80.4~102.1% by solvent/solvent extraction method and 89.9~106.4% by sweep co-distillation method except 46.6~61.2% of PG at corresponding spiked concentractions. The maximun recovery rates of antioxidnts were obtained when extraction time and extraction temperature used in UNITREX were 20min and 21$0^{\circ}C$ respectively. In the recovery rates with the activation of florisil when 2% ofwater was added to florisil the highest recovery rates for TBHQ, BHA, BHT were obtained by sweep co-distillation met-hod. Therefore sweep co-distillation method showed less solvent simple operation and high recovery rate compared with solvent/solvent extraction method.

• Proceedings of the Korea Environmental Mutagen Society Conference
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• 2002.05a
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• pp.132-132
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• 2002

• Bulletin of the Korean Chemical Society
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• v.22 no.6
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• pp.629-632
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• 2001

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.11
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• pp.4405-4409
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• 2014

Reactive oxygen species (ROS), highly reactive molecules, are produced by living organisms as a result of normal cellular metabolism and environmental factors, and can damage nucleic acids and proteins, thereby altering their functions. The human body has several mechanisms to counteract oxidative stress by producing antioxidants. A shift in the balance between oxidants and antioxidants in favor of oxidants is termed as "oxidative stress". Paradoxically, there is a large body of research demonstrating the general effect of oxidative stress on signaling pathways, less is known about the initial and direct regulation of signaling molecules by ROS, or what we term the "oxidative interface." This review focuses on the molecular mechanisms through which ROS directly interact with critical signaling molecules to initiate signaling in a broad variety of cellular processes, such as proliferation and survival (MAP kinases and PI3 kinase), ROS homeostasis, and antioxidant gene regulation (Ref-1 and Nrf-2). This review also deals with classification as well as mechanisms of formation of free radicals, examining their beneficial and deleterious effects on cellular activities and focusing on the potential role of antioxidants in preventing and repairing damage caused by oxidative stress. A discussion of the role of phytochemical antioxidants in oxidative stress, disease and the epigenome is included.

• The Korean Journal of Nuclear Medicine
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• v.26 no.1
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• pp.133-139
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• 1992

To improve the quality of $^{99m}Tc-methylenediphonate$ $(^{99m}Tc-MDP)$ for skeletal imaging, different composed $^{99m}Tc-MDP$ complexes were prepared with addition of antioxidants such as ascorbic acid, getisic acid, and p-aminobenzoic acid. To characterize the different $^{99m}Tc-MDP$ preparations, some physical and biochemical properties of $^{99m}Tc-MDP$ such as thermal stability, lipophilicity and bindability to serum protein were studied and organ distribution pattern of these complexes also compared. The thermal stabilities of $^{99m}Tc-MDP$ contained antioxidants were dependant mainly on pH, temperature, and elapsed time after the preparation. $^{99m}Tc-MDP$ complex contained gentisic acid as antioxidant was extremely unstable at alkaline condition. The most stable $^{99m}Tc-MDP$ was found in the presence of p-aminobenzoic acid. $^{99m}Tc-MDP$ complexes with antioxidants were very lipophilic but lipophilicity differences in antioxidants were not observed. The bindability of $^{99m}Tc-MDP$ to serum protein was not affect at pH $5.0\sim9.0$ by the different antioxidants. However, protein binding percentage of $^{99m}Tc-MDP$ with ascorbic acid was relatively low (22.7%) at pH 9.0. In biodistribution studies in mice, bone to muscle ratios of $^{99m}Tc-MDP$ preparations containing ascorbic acid, gentisic acid, and p-aminobenzoic acid were 15.3, 24.5, and 30.1, respectively. Im to our results, p-aminobenzoic acid is fond to be the most promising antioxidant.

• The Korean Journal of Physiology and Pharmacology
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• v.11 no.1
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• pp.9-13
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• 2007

Antioxidant properties have been proposed as a mechanism for the putative anti-inflammatory effects of phenolic compounds. To reveal the relationship between antioxidant activity and anti-inflammatory effects of various antioxidants, we measured 1, 1-diphenyl-2-picryhydrazyl(DPPH)-reducing activity and examined the inhibitory effects on LPS-induced inflammation-related gene expression in the BV2 microglial cell line. Lipopolysaccharide(LPS)(0.2 ${\mu}g/ml$) was used with or without antioxidants to treat cells, and the regulation of iNOS and cytokine gene expression was monitored using an RNase protection assay(RPA). Although, all tested antioxidants had similar DPPH-reducing activity and inhibited nitrite production, but the curcuminoid antioxidants(ferulic acid, caffeic acid, and curcumin) inhibited LPS-induced gene expression(iNOS, $TNF-\alpha,\;IL-1{\beta}$, IL-6, and IL-1 Ra) in a concentration-dependent manner. Other tested antioxidants did not exhibit the same effects; N-acetylcysteine(NAC) only began to suppress $IL-1{\beta}$ gene expression just below the concentration at which cytotoxicity occurred. Moreover, the antioxidant potency of curcuminoids appeared to have no correlation with anti-inflammatory potency. Only curcumin could inhibit LPS-induced microglial activation at a micromolar level. These data suggest that curcumin may be a safe antioxidant possessing anti-inflammatory activity.

• Proceedings of the Korea Environmental Mutagen Society Conference
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• 2004.11a
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• pp.110-110
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• 2004

• Proceedings of the Korean Society of Toxicology Conference
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• 2002.05a
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• pp.132-132
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• 2002

Effects of antioxidant vitamins were investigated in di(2-ethylhexyl) phthalate (DEHP)-induced endocrine disruption toxicity. After rats were treated with DEHP, and vitamin C and vitamin E were supplemented for 30 days.(omitted)

• Bulletin of the Korean Chemical Society
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• v.24 no.12
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• pp.1853-1855
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• 2003

• Korean Journal of Animal Reproduction
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• v.21 no.4
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• pp.345-353
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• 1997

Antioxidants and antioxidants with somatic cell co-culture, bovine oviduct epithelial cells(BOEC) and buffalo rat liver cells(BRLC), were studied as a mean of increasing the development and intracellular glutathione(GSH) concnetrations of bovine embryos derived from in vitro matured(IVM) and in vitro fertilized(IVF) oocytes. Cell numbers and intracellular GSH concentrations of blastocysts were also counted. The developmental rate beyond morula stages in CRlaa containing taurine(2.5mM), superoxide dismutase(SOD, 600U) and catalase(250U) were 1%, 75.0%, 64.8% and 62.3%, respectively. The developmental rate in antioxidant groups was significantly higher than in control(P<0.05). The intracellular GSH concentrations of blastocysts cultured in 0, 2.5mM taurine, 600U SOD and 250U catalase were 33.8pM, 39.3pM, 42.3pM and 54.8pM, respectively. This result indicated that the developmental rates and intracellular GSH concentrations of catalase group was significantly higher than any other groups(P<0.05). The developmental capacity in CRlaa plus various antioxidants co-cultured with BOEC were 55.3%(control), 74.1%(2.5mM taurine), 66.7%(600U SOD) and 70.7%(250U catalase) and in CRlaa plus various antioxidants co-cultured with BRLC in control, 2.5mM taurine, 600U SOD and 250U catalase were 63.8%, 75.5%, 71.0% and 73.5%, respectveily, the intracellular GSH concentrations of blastocyst embryos co-cultured with BOEC and BRLC in CRlaa with 0.25mM taurine, 600U SOD and 250U catalase were 73.4pM and 64.4pM, 79.9pM and 67.5pM, 82.3pM and 71.7pM, and 83.0pM and 80.0pM, respectively. Cell numbers of blastocysts were not difference in all experimental groups. These studies indicate that andtioxidants and antioxidant with somatic cell co-culture can increase the proportion of embryo that developed into morula and blastocysts, and the intracellular GSH concentrations of blastocyst embryos.