• Journal of Nutrition and Health
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• 제35권2호
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• pp.229-236
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• 2002

Cataracts are the leading cause of blindness worldwide and are characterized by increased opacity of the lens that significantly diminishes visual acuity. It has been suggested that increased risk of lens opacities are associated with age, exposure to sunlight, diabetes, smoking, and poor nutrition. Antioxidant nutrients have born demonstrated to protect the lens membrane and protein against damage due to oxidative stress. The purpose of this study was to investigate the antioxidant system in the blood of cataract patients. The status of the blood antioxidant system was evaluated based on the levels of antioxidant vitamins and minerals as well as glutathione peroxidase (GSH-Px) and malondialdehyde (M7A) activity in 34 patients with cataracts (17 male and 17 female) and 45 control subjects (20 male and 25 female). After adjusting for age, the results showed significantly lower levels of antioxidant vitamins such as lycopene (M : p < 0.05, F: p < 0.01), zeaxanthin (F: p < 0.01), ${\gamma}$-tocopherol (F: p < 0.01) and ascorbic arid (M: p < 0.05) in the cataract patients than in the control subjects. In contrast, the concentration of cryptoxanthin (F : p < 0.07) showed a significantly higher value in the cataract patients. The serum level of the antioxidant mineral Zn (M : p < 0.01) was found to be significantly lower in the cataract patients while the ratio of cu/zn appeared significantly higher (M : p < 0.05). Significantly higher (M : p < 0.01, F: p < 0.05) concentrations of MDA in serum was found in the cataract patients as compared to the control subjects. GSH-Px activity was significantly lower (F: p < 0.05) in 71e cataract patients. In conclusion, the antioxidant system may play an important roll in cataract creation. Further studies are needed to clarify the mechanisms underlying these findings and to establish preventive measures with an emphasis on antioxidant nutrition for cataract patients.

• 대한의생명과학회지
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• 제12권1호
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• pp.49-52
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• 2006

To elucidate the effect of antioxidant complex containing $\beta-carotene$, vitamin E, vitamin C, Ginkgo Biloba leaf extract and selenium on oxygen :tree radical production and detoxification system, rats were fed normal diet and normal diet with antioxidant complex 0.1%, 0.3% and 0.5% for 3 weeks. Feed efficiency ratio, changes in body weight, weight gain and amounts of feces of rat are similar in four groups. Liver weight per body weight and hepatic lipid peroxide weight increased in 0.5% group. However, hepatic glutathione contents in all antioxidant complex added groups were significantly increased compare with normal control group. On the other hand, the activity of xanthine oxidase was a little increased due to the amounts of antioxidant complex. Superoxide dismutase and gutathione peroxidase activity of 0.1% antioxidant complex added group were increased about $10{\sim}20%$ in comparison to normal control group. These results suggest that the supplementation of antioxidant complex 0.1% to basal diet may reduce the hepatic damage caused by free radicals.

• 약학회지
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• 제50권1호
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• pp.58-63
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• 2006

The antioxidant enzyme (AOE) system plays an important role in the defense against oxidative stress damage. To determine whether myricetin or myricetin/taurine can exert antioxidative effects not only by modulating the AOE system directly but also by scavenging free radical, we investigated the influence of the myricetin and taurine on cell viability ROS level, activities of different antioxidant enzyme, and the expression of different antioxidant enzyme. As results, the cell viability showed inhibition of the proliferation with treatment of 'myricetin' or 'myricetin with taruine', respectively, with dose-dependent manner. Compared to control, the treatment of 'myricetin' decreased activities and gene expressions of superoxide dismutase (SOD), and glutathione peroxidase (GPx). However, combined treatment of 'myricetin with taurine' increased activities and gene expressions of the SOD, GPx, and catalase (CAT). In addition, the combined treatment of 'myricetin with taurine' somewhat decreased ROS levels, compared to the treatment of 'myricetin'. In conclusion, our study provides that the combined treatment of different antioxidants can enhance antioxidant effects.

• Clinical and Experimental Pediatrics
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• 제56권3호
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• pp.107-111
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• 2013

Preterm infants are vulnerable to the oxidative stress due to the production of large amounts of free radicals, antioxidant system insufficiency, and immature oligodendroglial cells. Reactive oxygen species (ROS) play a pivotal role in the development of periventricular leukomalacia. The three most common ROS are superoxide ($O2^{\cdot-}$), hydroxyl radical ($OH^{\cdot}$), and hydrogen peroxide ($H_2O_2$). Under normal physiological conditions, a balance is maintained between the production of ROS and the capacity of the antioxidant enzyme system. However, if this balance breaks down, ROS can exert toxic effects. Superoxide dismutase, glutathione peroxidase, and catalase are considered the classical antioxidant enzymes. A recently discovered antioxidant enzyme family, peroxiredoxin (Prdx), is also an important scavenger of free radicals. Prdx1 expression is induced at birth, whereas Prdx2 is constitutively expressed, and Prdx6 expression is consistent with the classical antioxidant enzymes. Several antioxidant substances have been studied as potential therapeutic agents; however, further preclinical and clinical studies are required before allowing clinical application.

• 한국연초학회지
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• 제14권2호
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• pp.168-195
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• 1992

Pulmonary system is a target organ and primary defense mechanism against environmental oxidants and polutants. Enzymatic and nonenzymatic antioxdant defense mechanisms undoubtedly protect the lung from oxidants even endogenous oxidative stress. In addition, new ways of augmenting pulmonary antioxidant defenses are developed, which can be used to support the intrinsic antioxidants. Therefore, improved understanding of antioxidant defense mechanisms will increase our knowledge of the cause and will suggest rational approaches for treating and preventing oxidant-induced lung injury. In this review, we discuss the formation and scavenging of free radicals, and the strategies for antioxidant defense of pulmonary system.

• Food Science and Biotechnology
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• 제16권2호
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• pp.177-182
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• 2007

The beneficial effects of fruits, vegetables, and beverages on human health have been attributed to their antioxidant activities. Therefore, antioxidant activity of food products is recognized as one of the important parameters in determining their functional values. Until now, antioxidant activity has been measured by various chemical and biological methods; however, many factors confound the reliability and reproducibility of measurements of antioxidant activity of food. In vitro methods may provide a useful indication of antioxidant activity but their results may not translate to the human biological system, while in vivo tests are difficult to carry out due to the intricate processes of uptake, cellular transportation, and metabolism of individual antioxidant components. Therefore, as long as these limitations exist, our best option is to measure the antioxidant activity in food directly. This review briefly summarizes currently available methods for the measurement of antioxidant activity in food and examines their respective validity.

• 한국식품저장유통학회지
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• 제7권4호
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• pp.373-379
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• 2000

유백피의 천연항산화제로서의 이용성을 검토하기 위하여 각종 용매로 유백피 추출물을 제조하여 lard emulsion에 첨가하여 6$0^{\circ}C$에서 저장하면서 항산화 활성을 비교하고 항산화 활성이 우수한 추출물을 용매별로 분획하여 항산화 활성, 분획물의 첨가농도의 결정 및 기질특이성을 측정하였다. 또한 생체내에서도 분획물의 항산화 효과를 살펴보기 위하여 흰쥐 간 micmsome 을 사용하여 유도된 지질 과산화 반응에 대한 억제 효과를 측정하였다. 유백피의 추출물은 물추출물에서 가장 강력한 항산화 활성을 나타내었다. 물추출물의 용매분획별 항산화 활성은 ethyl acetate 분획에서 가장 높았으며 ethyl acetate 분획물 0.05%(w/w) 첨가는 합성 항산화제인 BHA(0.01%, w/w)와 비슷한 항산화 활성이었다. Ethyl acetate 분획물 0.05%(w/w)는 돈지, 대두유, 팜유 및 옥수수유에서도 항산화 활성을 나타내었다. 간 microsome 분획을 이용한 지질 과산화 억제 효과는 비효소적 지질 과산화 검정계인 Fe$^{++}$ascorbate system과 효소적 지질 과산화 검정계인 Fe$^{++}$-ADP/NADPH system 모두에서 ethyl acetate 분획물 첨가가 caffeic acid보다 강한 억제율을 보였다.

• Natural Product Sciences
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• 제10권6호
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• pp.296-301
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• 2004

Previously, a flavonoid fraction, which consisted mainly of protocatechuic acid, fustin, fisetin, sulfuretin, and butein, here named RCMF $({\underline{R}}VS\;{\underline{c}}hloroform-{\underline{m}}ethanol\;{\underline{f}}raction)$, was prepared from a crude acetone extract of Rhus verniciflua Stokes (RVS) which is traditionally used as a food additive and as an herbal medicine. In this study, we evaluated the effects of RCMF on the antioxidant defense system using embryonic normal hepatic cell line (BNL CL.2) and its SV40-mediated transformed cell line (BNL SV A.8). This study demonstrates that RCMF selectively stimulated the antioxidant defense system of normal cells, as BNL CL.2 cells proved to be more sensitive to RCMF-mediated increases of superoxide dismutase, catalase, glutathione, and glutathione reductase than BNL SV A.8 cells. In particular, RCMF caused a significant increase in the malonaldehyde content of BNL SV A.8 cells, which is believed to be closely associated with cytotoxicity of RCMF and RCMF-mediated growth inhibition. Collectively, our findings suggest that the flavonoid fraction, RCMF, selectively stimulates the antioxidant defense system in normal rather than hepatic tumor cells.

• 한국조리학회지
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• 제24권2호
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• pp.103-111
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• 2018

The objectives of the present study were to examine the antioxidant activity of autofocusing fractions from egg white protein hydrolysates and obtain higher antioxidant peptide fraction, which could be applied to the food model system. Alkaline protease hydrolysate of egg white protein exerted higher antioxidant activities than other protein hydrolysates and were fractionated on the basis of the amphoteric nature of sample peptides by preparative isoelectric focusing without toxic solvents and reagents, which is termed autofocusing. Neutral and basic fractions showed higher 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity than the acidic fractions. The acidic and neutral fractions showed higher hydroxyl (OH) radical scavenging activity and oxygen radical absorbance capacity (ORAC) values than the basic fractions. The acidic fractions showed higher metal chelating activity than basic fractions. Antioxidant activities of some autofocusing fractions except for ORAC showed higher compared to the crude hydrolysate. These results suggest that peptides fractions from egg white protein are effective antioxidant, and that autofocusing could be useful to increase antioxidant activity for application to food system.

• 약학회지
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• 제49권1호
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• pp.86-91
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• 2005

Flavonoids are class of polyphenolic compounds widely distributed in the plant kingdom, which display a variety of biological activities, including antiviral, antithrombotic, antiinflammatory, antihistaminic, antioxidant and free-radica 1 scavenging abilities. The antioxidant enzyme (AOE) system plays an important role in the defense against oxidative stress insults. To determine whether flavonoid, myricetin can exert antioxidative effects not only directly by modulating the AOE system but also scavenging free radical, we investigated the influence of the flavonoid myricetin on cell viability, different antioxidant enzyme activities, ROS level and the expression of different antioxidant emzyme in B16F10 murine melanoma cells. Myricetin in a concentration range from 6.25 to $50\;{\mu}M$ decreased superoxide dismutase (SOD) and glutathione peroxidase (GPx) enzyme activities, but catalase (CAT) activity was increased. In the myricetin-treated group, ROS levels were decreased dose-dependently. Antioxidant enzyme expression was measured by RT-PCR. Myricetin treatment of B16F10 cells increased catalase expression. Expression levels of copper zinc superoxide dismutase (CuZn SOD) were not affected by exposure of myricetin. Manganese superoxide dismutase (Mn SOD) and GPx expression levels decreased slightly after myricetin treatment. In conclusion, the antioxidant capacity of myricetin was due to CAT and free-radical scavenging.