• Journal of Korean Society of Forest Science
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• v.96 no.1
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• pp.14-20
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• 2007

In order to examine the differences in antioxidant enzyme activities which represent defence mechanism to stressful environments, and soil properties between healthy and declining (or unhealthy) trees, we selected three sites, Witseorum, Youngsil and Sungpanak (Jindallebat). Antioxidant enzymes including Ascorbate peroxidase (APX) and Glutathione Reductase (GR), forest soil properties including soil texture, soil pH, organic matter, total nitrogen, available phosphate, cation exchange capacity, exchangeable cation content and nutrient contents in leaves of Abies koreana (Korean fir) trees were analyzed. There were no significant differences between healthy and declining trees in GR activity. However, seasonal difference in antioxidant enzyme activity was observed. GR activity was lower in June and August than that of September. Soil chemical and physical properties of each site showed a tendency that organic content, total nitrogen content, available phosphorus, cation exchange capacity and cation content were lower at the site of declining trees than the site of healthy trees.

• Journal of fish pathology
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• v.27 no.2
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• pp.115-125
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• 2014

The effects of waterborne arsenic (As) exposure on antioxidant defense were studied in liver and gills of tilapia, Oreochromis niloticus under thermal stress. Tilapia were exposed to different As concentrations (0, 200 and $400{\mu}g/L$) at three water-temperatures (WT; 20, 25 and $30^{\circ}C$) for 10 days. In antioxidant response, glutathione (GSH) levels, glutathione reductase (GR), glutathione peroxidase (GPx) and glutathione S-treansferase (GST) activities were significantly decreased depend on WT in the gills after As exposure. Also, the range of fluctuation in these enzymes activities was most significantly increased at $30^{\circ}C$ in the liver of tilapia exposed to As. The present findings suggest that a simultaneous stress by temperature change and As exposure could accelerate the alteration in antioxidant enzymes activities of tilapia.

• Journal of the Korea Convergence Society
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• v.12 no.11
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• pp.403-410
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• 2021

This paper aimed to increase the functionality and competitiveness of rice bran, which is used as an alternative food and cosmetic raw material, through fermentation. As a result of comparing the enzyme activity of 𝛼-amylase, CMCase, 𝛽-glucosidase, protease, etc. of fermented rice bran using standard strains with 6 strains with excellent enzyme activity among 50 strains of Saccharomycopsis fibuligera isolated from 5 types of Nuruk, A8 strain showed excellent enzyme activity of 13.7%, 21.1%, 50.3%, and 10.0% compared to the KCTC 7806 strain. As a result of the ABTS and DPPH tests as a result of fermentation, it was confirmed that rice bran fermented with A8 had 1.12 times and 1.28 times more antioxidant activity than rice bran fermented with KCTC 7806 strain. In this paper, it was possible to confirm the S. fibuligera A8 strain superior to the standard S. fibuligera strain KCTC 7806.

• The Korean Journal of Mycology
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• v.28 no.1
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• pp.55-59
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• 2000

This study was carried out to investigate the antioxidative and chemopreventive effects of the extracts from Polyozellus multiplex, an edible mushroom through in vitro and in vivo assay. Polyozellus multiplex fractions were assayed for its antioxidative effect with colony formation assay. Polyozellus multiplex methanol extract and water fraction showed protective effects against the cytotoxicity of $H_2O_2$. The modifying effects of Polyozellus multiplex methanol extract and water fraction on the induction of carcinogenesis by N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) were investigated in Wistar rats. The GSH content was decreased by MNNG treatment but was increased by adding Polyozellus multiplex water fractions. Also the activity of glutathione S-transferase and the superoxide dismutase levels were increased by the treatment of Polyozellus multiplex water fractions more than with MNNG alone. In addition to the Polyozellus multiplex water fraction increased the p53 expression as compared with the value of MNNG alone.

• Korean Journal of Agricultural and Forest Meteorology
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• v.6 no.1
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• pp.24-29
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• 2004

The purpose of this study was to identify the effects of air pollution on the street trees in Seoul. Ten Gingko biloba street trees were selected in both Jongno(polluted area as a control) and Yangjae(non-polluted area) to investigate chlorophyll contents, photosynthesis and antioxidant enzymes such as APX(Ascorbate peroxidase) and GR(Glutathione reductase). The sampling, measurements and analysis were conducted in August. Chlorophyll contents and photosynthesis of Gingko biloba grown in Yangjae were higher than those of Jongno in the August measurement. In contrast, APX and GR activities of Gingko biloba grown in Yangjae were lower than those of Jongno. The observed tree responses are considered to be atypical compensatory response to polluted locations.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.1
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• pp.16-23
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• 2014

Red yeast rice (RYR) has been known to exhibit various biological effects, including anti-hyperlipidemia, antioxidant, anti-tumor, and anti-inflammtory activities. Oxidative stress is a main risk factor in the development of cardiovascular disease, such as atherosclerosis. Therefore, the aim of this study was to investigate the possible hypolipidemic and antioxidant effect of RYR on rats fed a high-cholesterol diet supplemented with either 0.2%, 1%, or 5% RYR for 4 weeks. We measured lipid profiles in the plasma and liver, antioxidant enzyme activities in plasma and erythrocyte, gene expression of antioxidant enzymes in the liver, and oxidative DNA damage in lymphocytes. The group supplemented with 0.2% RYR had total cholesterol level in plasma decreased by 24%, while the group supplemented with 5% RYR had high-density cholesterol increased by 20% compared to the control. The antioxidant enzyme activities were also affected by RYR supplementation. Total superoxide dismutase activities in plasma significantly decreased by 11% in the 1% RYR group, while these activities in the liver significantly decreased by 16% and 21% in the 1% and 5% supplemented group compared to the control, respectively. Glutathione peroxidase activities in plasma and erythrocytes increased 13% and 48% in the 1% RYR group, respectively. Catalase (CAT) activity in erythrocytes significantly increased by 49% and 68% in the 1% and 5% RYR group compared to the control, respectively. The gene expression of CAT was up-regulated 7.9 fold compared to the control in the 5% RYR supplemented group. These results suggest that RYR can control hyperlipidemia by improving the lipid profile and modulating oxidative stress.

• Journal of Korean Ophthalmic Optics Society
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• v.20 no.2
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• pp.237-246
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• 2015

Purpose: The present study was conducted to reveal the correlation of structural denaturation and decrease of enzyme activity when the antioxidative enzymes, superoxide dismutase (SOD) and catalase (CAT) were repeatedly exposed to UV-B, and further investigate whether the denaturation and inactivation of those enzymes can be effectively blocked by using UV-inhibitory RGP lens. Methods: Each enzyme solution was prepared from the standardized SOD and CAT, and repeatedly exposed to UV-B of 312 nm for 30 minutes, 1 hour and 2 hours a day over 1, 2, 3, 4 and 5 days. Structural denaturation of SOD and CAT induced by repeat UV-B irradiation was confirmed by the electrophoretic analysis, and their enzyme activity was determined by the colorimetric assay using the proper assay kit. At that time, the change in structure and activity of the antioxidant enzymes directly exposed to UV-B was compared to the case that UV-B was blocked by UV-inhibitory RGP lens. Results: SOD exposed repeatedly to UV-B showed the polymerization pattern in the electrophoretic analysis when it repeatedly exposed for 30 min a day, however, the change of its activity was less than 10%. On the other hand, CAT repeatedly exposed to UV-B reduced size and density of the electrophoretic band which indicated a structure denaturation, and its activity was significantly decreased. In the case that the repeat exposure time was longer, CAT activity was completely lost even though some enzyme band occurred in the electrphoretic analysis. In addition, the degeneration of CAT due to UV-B irradiation was inhibited to some extent by using RGP lens with a UV-B blocking of 63.7%, however, it was not completely inhibited. Conclusions: From these results, it was revealed that the structural denaturation of antioxidative enzymes was not perfectly correlated with the reduction in enzyme activity according to the type of enzyme. It is recommended to minimize the exposure time to UV when wearing contact lens, or wear the contact lenses having UV blocking rate of the FDA Class I blocker or the sunglasses having equivalent UV-blocking rate for reducing the damage of antioxidative enzymes induced by UV.

• Proceedings of the Korean Nutrition Society Conference
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• 1997.11b
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• pp.61-61
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• 1997

• The Science & Technology
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• v.31 no.7 s.350
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• pp.80-81
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• 1998

축산물의 가공과 이용에 관한 연구를 진행 하고 있는 강원대 축산가공학과 이성기 교수는 '냉동 세절돈육에서 소금이 지방산화 촉진과 항산화효소 역가에 미치는 영향'이라는 논문을 발표해 세계적인 관심을 모으고 있다. 이교수는 이러한 연구를 통해 돈육에 첨가한 소금이 냉동저장중에 지방산화를 급증시키는 반변 돈육 속에 함유된 항산화 효소들의 역가는 감소시켰다고 밝히고 있다.

• Proceedings of the Korea Society of Environmental Biology Conference
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• 2005.12a
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• pp.102-103
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• 2005