• Journal of Photoscience
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• 제8권1호
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• pp.13-17
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• 2001

Cucumber leaves subjected to light chilling stress exhibit a preferential inactivation of photosystem(PS) I relative to PSII, resulting in the photoinhibition of photosynthesis. In light chilled cucumber leaves, Cu/Zn-Superoxide dismutase(SOD) is regarded as a primary target of the light chilling stress and its inactivation is closely related to the increased production of reactive oxygen species. In the present study, we further explored that inactivation of PSI in cucumber leaves is not a light chilling specific, but general to various oxidative stresses. Oxidative stress in cucumber leaves was induced by treatment of methylviologen(MV), a producer of reactive oxygen species in chloroplasts. MV treatment decreased the maximal photosynthetic O$_2$ evolution, resulting in the photoinhibition of photosynthesis. The photoinhibition of photosynthesis was attributable to the decline in PSI functionality determined in vivo by monitoring absorption changes around 820 nm. In addition, MV treatment inactivated both antioxidant enzymes Cu-Zn-superoxide dismutase and ascorbate peroxidase known sensitive to reactive oxygen species. From these results, we suggest that chloroplast antioxidant enzymes are the primary targets of photooxidative stress, followed by subsequent inactivation of PSI.

• Biomolecules & Therapeutics
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• 제3권3호
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• pp.223-228
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• 1995

In an attempt to define the effects of biphenyldimethyl dicarboxylate (DDB) on the lipid peroxidation and oxygen free radical scavenging enzymes activities in mercuric chloride-induced hepatotoxic rats, we studied malondialdehyde (MDA) level and the activities of catalase and superoxide dismutase (SOD) in liver of the rats at 24 hr after the injection of mercuric chloride. Sprague-Dalwey albino rats were injected subcutaneously with mercuric chloride (5 mg/kg) only and mercuric chloride (5 mg/kg) plus. DDB (200 mg/kg/day, p.o) is administered for 4 days prior to 3 days from the injection of mercuric chloride. The group treated with mercuric chloride showed significantly higher MDA level and lower catalase and SOD activities as compared with that of control group. The group treated with mercuric chloride plus DDB showed significantly lower MDA level and catalase activity and higher SOD activity as compared with that of mercuric chloride-treated group. These results suggest that the excessive oxygen free radicals resulting from the depression of superoxide dismutase activity is an important determinant in the pathogenesis of mercuric chloride-induced hepatotoxicity and DDB has antioxidant effects.

• 대한본초학회지
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• 제24권4호
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• pp.137-142
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• 2009

Objectives : This study was performed to investigate the antioxidant activities of isolated compounds from the shoot of Aralia elata. Methods : The methanol extract from the shoot of Aralia elata was fractionated into ethyl acetate, n-BuOH and $H_2O$ layers through solvent fractionation. Repeated silica gel, ODS column chromatography of n-BuOH layer afforded four flavonol glycosides. Their antioxidant activity was determined by measuring free radical scavenging activity by DPPH, ABTS and superoxide dismutase (SOD) like activity assay. Results : They were identified as quercetin 3,7-di-O-$\alpha$-rhamnopyranoside (1), quercetin 3-O-$\beta$-D-galactoside-7-O-$\alpha$-L-rhamnoside (2), kaempferol 3-O-$\beta$-glucosyl($1{\rightarrow}2$)-$\alpha$-rhamnoside-7-O-$\alpha$-rhamnoside (3) and quercetin 3-O-$\beta$-glucosyl($1{\rightarrow}2$)-$\alpha$-rhamnoside-7-O-$\beta$-rhamnoside (4) on the basis of spectroscopic data. The result showed that 1 is the most active compound in the DPPH and ABTS radical scavenging test. Conclusions : Isolated Compounds from the shoot of Aralia elata showed anti-oxidative effect.

• Journal of Animal Science and Technology
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• 제64권1호
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• pp.70-83
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• 2022

A set of studies was performed to determine the influence of dietary ZnO concentration and source during two phases (days 0 to 14 and days 15 to 28). Experiment 1: 168 weaned piglets were allocated to four treatment groups in six replicates. The treatments included a basal diet without ZnO supplementation (control), 2,500 mg ZnO/kg (In2500), 500 mg nano-ZnO/kg (N500), and 150 mg nano-ZnO/kg (N150). Experiment 2: 168 weaned piglets were divided into three treatment groups with eight replicates. The treatments included control, In2500, N300, and 150 mg nano-ZnO/kg (N150). An in vitro trial showed that the growth of Listeria monocytogenes, Escherichia coli, and Salmonella typhimurium was inhibited when exposed to 300 and 500 ppm of ZnO after 24 h of incubation. In experiment 1, the average daily gain (ADG) by the pigs was improved in the N500 and IN2500 treatment groups. Colonization of coliforms and Clostridium spp. significantly decreased in the pigs fed the N500 and IN2500 diets in phase 1. The total plasma antioxidant capacity was greater in the IN2500 and N500 treatment groups than in the control. Superoxide dismutase (SOD) activity was greater in pigs fed the IN2500 (phase 1) or the IN2500 and N500 (phase 2) diets than in the control and N150 treatment group. In experiment 2, pigs in the N300 treatment group showed a higher ADG and lower fecal score colonization of coliforms and Clostridium spp. compared with those in the N150 treatment group. In conclusion, nano-ZnO at a dose of 300 ppm showed the same growth as the pharmacological dose of Zn. This provides an option to the pharmacological dose.

• 대한약리학회지
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• 제24권1호
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• pp.83-92
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• 1988

세포질 내 칼슘 농도의 증가는 다형핵 백혈구의 산화성 대사를 자극하는 주요 인자로 여겨지고 있다. 활성화된 다형핵 백혈구로부터 lysosomal enzyme의 유리는 세포내 cyclic nucleotide농도에 따라 조절될 수 있지만 신경전달물질과 ${\beta}$-아드레날린 또는 무스카린성 수용체의 결합에 따른 그밖의 반응은 아직도 분명하지 않다. 덧붙여, ${\alpha}$-아드레날린성 수용체의 중개에 의한 다형핵 백혈구의 기능은 알려져 있지 않다. Atropine, phentolamine과 propranolol은 활성화된 다형핵 백혈구의 칼슘흡수, superoxide 생성, NADPH oxidase 활성도 그리고 식작용을 억제하였으며, 이에 반하여 carbachol과 isoproterenol은 활성화된 세포의 반응을 약간 더 자극하였다. Carbachol또는 isoproterenol 의하여 항진된 superoxide 생성은 각각 그들의 길항제인 atropine과 propranolol 의하여 억제되었다. 활성화된 다형핵 백혈구의 반응은 chlorpromazine, verapamil과 dantrolene에 의하여 억제되었으나 lithium에 의 하여 약긴 항진되었다. 한편 chlorpromazine과 dibucaine은 NADPH oxidase 활성도에 영향을 주지 않았다. Atropine, phentolamine과 propranolol은 칼슘에 의존적인 식작용을 억제 하였다. 이상의 결과로부터 atropine, phentolamine과 propranolol은 칼슘 유입을 억제하고 자율 신경계의 수용체와 연관이 있는 NADPH oxidase계에 직접 작용함으로써 활성화된 다형핵 백혈구로부터 superoxide 생성을 억제할 것으로 시사되었다.

• 대한화장품학회지
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• 제31권2호
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• pp.207-212
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• 2005

강한 천연 생리활성물질인 폴리페놀과 탄닌을 다량 함유한 석류를 노화방지제 및 기능성화장품의 화장품 원료로 이용할 수 있는 가능성을 제시하고자, 과즙과 과피 및 종자유로 나누어 분리추출한 후, DPPH radical과 superoxide의 소거작용, 세포내 $H_2O_2$와 hydroperoxide 및 superoxide 생성 억제작용에 미치는 영향에 관하여 실험하여 항산화 작용을 비교 평가하였다. 석류과피 메탄올 추출액은 전반적으로 가장 유의성 있는 항산화 작용을 보였다. 자체적인 항산화 작용뿐만 아니라 세포내에서 free radical이 생성되는 것을 억제하는 작용도 있는 것으로 여겨지며, 석류과즙 농축액은 free radical을 소거하는 항산화 작용이 있으며, 또한 석류 종자유는 강한 hydroperoxide 생성 억제효과를 나타내어, 특히 hydroxy기를 가진 readical의 생성을 억제하는데 효과가 있는 것으로 사료된다. 이상과 같은 결과로 보아, 석류의 과즙보다는 과피의 추출물이 항산화 작용이 더 뛰어난 것을 알 수 있었으므로 피부미용에 관련된 건강보조식품 개발시 과피성분을 함유한 추출물을 원료로 사용하는 것이 효과적이라고 사료되며, 특히 피부 주름 방지제 등과 같은 기능성 화장품을 개발하고자 할 때는 석류 종자유를 화장품 원료로 하여 개발하는 것이 더 효과적이라고 사료된다.

• 한국식품저장유통학회지
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• 제9권2호
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• pp.253-259
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• 2002

민들레 잎과 뿌리로부터 물추출물을 제조하여 항산화 활성 및 라디칼 소거활성을 분석하기 위하여 linoleic acid에 대한 과산화물 생성저해율, DPPH radical에 대한 소거활성, chemiluminescence를 이용한 hydroxyl radical에 대한 소거활성, EPR을 이용한 superoxide anion radical에 대한 소거활성및 hydrogen peroxide에 대한 소거활성을 측정하였다. 그 결과, 민들레 잎의 물추출물이 뿌리의 물추출물 보다 지방산에 대한 과산화물 생성 저해율이 높았고, DPPH radical, hydroxyl radical, superoxide anion radical 및 hydrogen peroxide에 대한 소거활성 역시 매우 높은 것으로 나타났다.

• Natural Product Sciences
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• 제8권1호
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• pp.26-29
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• 2002

The MeOH extract of Sorbus commixta (Rosaceae) exhibited strong DPPH radical scavenging activity, and through activity-guided fractionation two antioxidant compounds were isolated and identified as $catechin-7-O-{\beta}-D-xylopyranoside$ (1) and $catechin-7-O-\;{\beta}-D-apiofuranoside$ (2) by physicochemical and spectrometric methods. To evaluate the antioxidant effect of these compounds, some in vitro tests, such as the DPPH radical scavenging activity test, the superoxide radical scavenging activity test and the lipid peroxidation inhibitory activity test, were performed. Compounds 1 and 2 showed stronger activities than both a-tocopherol and butylated hydroxy anisole (BHA) in each assay.

• Preventive Nutrition and Food Science
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• 제14권1호
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• pp.86-89
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• 2009

In this study, we investigated the free radical [1,1-diphenyl-2-picrylhydrazyl (DPPH), hydroxyl radical (${\cdot}OH$) and superoxide anion (${O_2}^-$)] scavenging activity of MeOH extract and 3 fractions of Citrus junos. Of the tested fractions, the BuOH fraction showed the strongest DPPH scavenging activity, showing the $IC_{50}$ values of 63.4 mg/mL. Therefore, we continuously carried out DPPH, ${\cdot}OH$ and ${O_2}^-$ scavenging activity tests of BuOH fraction of Citrus junos. The BuOH fraction of Citrus junos inhibited DPPH radical to 97.5% at a concentration of 1000 mg/mL and the scavenging activities were increased concentration-dependently. In addition, BuOH fraction from Citrus junos also scavenged ${\cdot}OH$ in a concentration dependent manner from 5 to 1000 mg/mL. Furthermore, BuOH fraction showed about 56% ${O_2}^-$-scavengimg activity at 25 mg/mL concentration but, the scavenging activities were not enhanced in a dose dependent manner. The present results suggest that BuOH fraction of Citrus junos would have the protective potential from oxidative stress induced by free radicals.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.235-235
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• 2017

Chromium (Cr) toxicity is hazardous to the seed germination, growth, and development of plants. ${\gamma}$-Aminobutyric acid (GABA) is a non-protein amino acid and is involved in stress tolerance in plants. To investigate the effects of GABA in alleviating Cr toxicity, we treated eight-d-old mustard (Brassica juncea L.) seedlings with Cr (0.15 mM and 0.3 mM $K_2CrO_4$, 5 days) alone and in combination with GABA ($125{\mu}M$) in a semi-hydroponic medium. The roots and shoots of the seedlings accumulated Cr in a dose-dependent manner, which led to an increase in oxidative damage [lipid peroxidation; hydrogen peroxide ($H_2O_2$) content; superoxide ($O{_2}^{{\cdot}-}$) generation; lipoxygenase (LOX) activity], MG content, and disrupted antioxidant defense and glyoxalase systems. Chromium stress also reduced growth, leaf relative water content (RWC), and chlorophyll (chl) content but increased phytochelatin (PC) and proline (Pro) content. Furthermore, supplementing the Cr-treated seedlings with GABA reduced Cr uptake and upregulated the non-enzymatic antioxidants (ascorbate, AsA; glutathione, GSH) and the activities of the enzymatic antioxidants including ascorbate peroxidase (APX), monodehydroascorbate reductase (MDHAR), dehydroascorbate reductase (DHAR), glutathione reductase (GR), glutathione peroxidase (GPX), superoxide dismutase (SOD), catalase (CAT), glyoxalase I (Gly I), and glyoxalase II (Gly II), and finally reduced oxidative damage. Adding GABA also increased leaf RWC and chl content, decreased Pro and PC content, and restored plant growth. These findings shed light on the effect of GABA in improving the physiological mechanisms of mustard seedlings in response to Cr stress.