• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2010년도 정기총회 및 추계학술발표회
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• pp.14-14
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• 2010

Vitamin C (ascorbic acid) is an essential component for collagen biosynthesis and also for the proper functioning of the cardiovascular system in humans. Unlike most of the animals, humans lack the ability to synthesize ascorbic acid on their own due to a mutation in the gene encoding the last enzyme of ascorbate biosynthesis. As a result, vitamin C must be obtained from dietary sources like plants. In this study, we have developed two different kinds of transgenic potato plants (Solanumtuberosum L. cv. Taedong Valley) overexpressing strawberry GalUR and mouse GLoase gene under the control of CaMV 35S promoter with increased ascorbic acid levels. Integration of the these genes in the plant genome was confirmed by PCR and Southern blotting. Ascorbic acid(AsA) levels in transgenic tubers were determined by high-performance liquid chromatography(HPLC). The over-expression of these genes resulted in 2-4 folds increase in AsA intransgenic potato and the levels of AsA were positively correlated with increased geneactivity. The transgenic lines with enhanced vitamin C content showed enhanced tolerance to abiotic stresses induced by methyl viologen(MV), NaCl or mannitol as compared to untransformed control plants. The leaf disc senescence assay showed better tolerance in transgenic lines by retaining higher chlorophyll as compared to the untransformed control plants. Present study demonstrated that the over-expression of these gene enhanced the level of AsA in potato tubers and these transgenics performed better under different abiotic stresses as compared to untransformed control. We have also investigated the mechanism of the abiotic stress tolerance upon enhancing the level of the ascorbate in transgenic potato. The transgenic potato plants overexpressing GalUR gene with enhanced accumulation of ascorbate were investigated to analyze the antioxidants activity of enzymes involved in the ascorbate-glutathione cycle and their tolerance mechanism against different abiotic stresses under invitro conditions. Transformed potato tubers subjected to various abiotic stresses induced by methyl viologen, sodium chloride and zinc chloride showed significant increase in the activities of superoxide dismutase(SOD, EC 1.15.1.1), catalase, enzymes of ascorbate-glutathione cycle enzymes such as ascorbate peroxidase(APX, EC 1.11.1.11), dehydroascorbate reductase(DHAR, EC 1.8.5.1), and glutathione reductase(GR, EC 1.8.1.7) as well as the levels of ascorbate, GSH and proline when compared to the untransformed tubers. The increased enzyme activities correlated with their mRNA transcript accumulation in the stressed transgenic tubers. Pronounced differences in redox status were also observed in stressed transgenic potato tubers that showed more tolerance to abiotic stresses when compared to untransformed tubers. From the present study, it is evident that improved to lerance against abiotic stresses in transgenic tubers is due to the increased activity of enzymes involved in the antioxidant system together with enhanced ascorbate accumulated in transformed tubers when compared to untransformed tubers. At moment we also investigating the role of enhanced reduced glutathione level for the maintenance of the methylglyoxal level as it is evident that methylglyoxal is a potent cytotoxic compound produced under the abiotic stress and the maintenance of the methylglyoxal level is important to survive the plant under stress conditions.

• Natural Product Sciences
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• 제25권3호
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• pp.255-260
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• 2019

Piper nigrum L. (Piperaceae), which is a well-known food seasoning, has been used as a traditional medicine for the treatment of vomiting, abdominal pain, diarrhea and anorexia in Korea, China and Japan. Methanol extract from the fruit of P. nigrum was successively partitioned as n-hexane, methylene chloride, ethyl acetate, n-butanol and $H_2O$ soluble fractions. Among those fractions the ethyl acetate soluble fraction showed the most potent DPPH radical scavenging activity, and piperine was isolated from the ethyl acetate fraction. To know the antioxidant activity of piperine, we tested the activities of superoxide dismutase (SOD) and catalase together with oxidative stress tolerance and intracellular ROS level in Caenorhabditis elegans. To investigate whether piperine-mediated increased stress tolerance was due to regulation of stress-response gene, we quantified SOD-3 expression using transgenic strain including CF1553. Consequently, piperine enhanced SOD and catalase activities of C. elegans, and reduced intracellular ROS accumulation in a dose-dependent manner. Moreover, piperine-treated CF1553 worms exhibited significantly higher SOD-3::GFP intensity.

• 생약학회지
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• 제54권2호
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• pp.66-71
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• 2023

Ethyl acetate (EA) soluble fraction of the Berberis amurensis (Berberidaceae) methanol extract showed the potent DPPH radical scavenging activity through Caenorhabditis elegans model system. The EA fraction was measured for the activity of superoxide dismutase (SOD), catalase, and oxidative stress tolerance by using C. elegans along with reactive oxygen species (ROS) level. In addition, SOD-3 expression was conducted using a transgenic strain (CF1553) to confirm that the regulation of the stress response gene is responsible for the increased stress tolerance of C. elegans treated by the EA fraction. As a result, the EA soluble fraction of B. amurensis increased SOD and catalase activity, and decreased ROS accumulation in a dose-dependent manner. Furthermore, the EA fraction-treated CF1553 worm showed higher SOD-3::GFP intensity than the control worm.

• 한국환경농학회지
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• 제16권2호
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• pp.142-148
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• 1997

중금속오염폐수처리에의 미생물 이용 가능성을 검토하기 위하여 중금속에 강한 내성을 지님과 동시에 균체내 중금속 축적능력이 우수한 중금속 내성균을 분리하여 competing ion, 대사저해제 등과 같은 외부 요인에 따른 균체내 중금속 축적변화를 조사한 결과는 다음과 같다. 중금속을 처리한 용액중 양이온인 $Al^{3+}$이온과 음이온인 $CO_3\;^{2-}$ 및 $PO_4\;^{2-}$이온이 competing ion으로 존재할 경우 중금속 내성균의 균체내 중금속 축적은 크게 감소되었으나, 그외 다른 양이온들과 음이온들에 대해서는 거의 영향을 받지 않았다. Cd, Zn 및 Cu 내성균주의 Cd, Zn 및 Cu 축적은 대사저해제에 의하여 크게 감소되었으나, Pb 내성균주에 의한 Pb 축적은 거의 영향을 받지 않는 것으로 나타나 Cd, Zn 및 Cu 내성균주의 Cd, Zn 및 Cu 축적은 에너지 의존적인 과정으로서 물질대사와 관련되어 있는 것으로 생각되었으며, Pb 내성균주의 Pb 축적은 에너지 비의존적인 과정으로서 물질대사와 관련이 별로 없는 물리적인 과정에 의하여 축적되는 것으로 생각되었다. 각 중금속 내성균주들은 해당 중금속 축적능력에 비하여 낮았으나 타 중금속들의 축적능력도 있었으며, 여러가지 중금속들을 동일 농도로 복합처리 하였을 경우 해당 중금속들의 축적능력이 타 중금속들에 비하여 매우 높게 나타나 각 중금속 내성균주들의 해당 중금속 축적은 선택적인 과정에 의하여 축적되는 것으로 생각되었다.

• Plant Biotechnology Reports
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• 제4권4호
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• pp.243-251
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• 2010

Nitric oxide (NO) has been shown to be involved in diverse physiological processes in microbes, animals and plants. In this study, the involvement of NO in the development and possible roles in oxidative stress protection of Chinese cabbage (Brassica rapa subsp. pekinensis cv. Samrack-ulgari) seedlings were investigated. Exogenous application of sodium nitroprusside (SNP) retarded root elongation, while increasing lateral root formation of Chinese cabbage. Plants showed no signs of external stress due to SNP application in true leaves. Cotyledons of 3-week-old Chinese cabbage plants were found to be highly sensitive to SNP application. Treated cotyledons displayed rapid tissue collapse and associated cell death. Although SNP application reduced root growth under normal growth conditions, it also enhanced methyl viologen (MV)-mediated oxidative stress tolerance. Analysis of SNP application to Chinese cabbage leaf disks, revealed SNP-induced tolerance against oxidative stresses by MV and $H_2O_2$, and evidence includes prevention of chlorophyll loss, superoxide anion (${O_2}^-$) accumulation and lipid peroxidation. This report supports a role for nitric oxide in modulating early seedling development, programmed cell death and stress tolerance in Chinese cabbage.

• Plant Biotechnology Reports
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• 제4권1호
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• pp.75-83
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• 2010

Glycine betaine has been reported as an osmoprotectant compound conferring tolerance to salinity and osmotic stresses in plants. We previously found that the expression of betaine aldehyde dehydrogenase 1 gene (OsBADH1), encoding a key enzyme for glycine betaine biosynthesis pathway, showed close correlation with salt tolerance of rice. In this study, the expression of the OsBADH1 gene in transgenic tobacco was investigated in response to salt stress using a transgenic approach. Transgenic tobacco plants expressing the OsBADH1 gene were generated under the control of a promoter from the maize ubiquitin gene. Three homozygous lines of $T_2$ progenies with single transgene insert were chosen for gene expression analysis. RT-PCR and western blot analysis results indicated that the OsBADH1 gene was effectively expressed in transgenic tobacco leading to the accumulation of glycine betaine. Transgenic lines demonstrated normal seed germination and morphology, and normal growth rates of seedlings under salt stress conditions. These results suggest that the OsBADH1 gene could be an excellent candidate for producing plants with osmotic stress tolerance.

• 미생물학회지
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• 제31권4호
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• pp.306-311
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• 1993

소수성 기질인 progesterone 을 수용성 반응액 속에 용해하기 위하여 사용되는 methanol 이 Rhizopus nigricans 의 성장과 progesterone 의 11.alpha.-hydroxylation 반응에 미치는 영향을 조사하고, 세포막 인지질의 불포화 지방산 함량을 증가시켜 유기용매에 대한 내성을 유도하였다. R. nigricans 의 균사체는 methanol 존재하에서 형태적인 변화를 일으켰으며, 세포막 인지질의 지방산 조성에 변화를 가져와 불포화 지방산, 특히 oleic acid 의 함량이 증가되었다. 세포의 고정화는 유기용매로부터 세포를 보호하여 progesterone 의 11-.alpha.-hydroxylation 율을 증가시켰다. 성장배지에 500.$\mu$g/l의 biotin 을 첨가하였을 때 세포막 인지질의 oleic acid 함랴이 증가되었으며 methanol 에 대한 내성이 증진되어 높은 progesterone 의 11 $\alpha$-hydroxylation 율을 얻을 수 있었다.

• 문화기술의 융합
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• 제5권3호
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• pp.327-332
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• 2019

현대 과학자들은 식물정화공정과 같은 새로운 기술로 중금속을 제거하려고 한다. 이런 최첨단 기술 중 하나는 토양의 특정 중금속을 제거하는 형질 전환 식물을 개발하는 것이다. 본 연구자는 T. goingense Metal Transport Protein 1 유전자와 TgMTP1 : GFP 유전자를 발현하는 형질 전환 벡터를 구축했다. 형질전환체 식물을 선택하여 형질 전환 된 유전자를 애기 장대 게놈에서 확인했다. 발현은 Arabidopsis 세포, 조직 및 기관의 여러 부분에서 확인되었다. Arabidopsis thaliana에서 TgMTP1 과발현하는 식물에 중금속이온이 처리되었을 때 형질 전환 식물체는 비 형질 전환 체보다 중금속 내성이 높았다. 추가 연구를 위해 4 (Zn, Ni, Co, Cd.)가지 중금속에 대한 내성이 향상된 형질 전환 식물을 선택했다. 선택된 T3 TgMTP1 과다 발현 애기 장대 식물은 중금속에 내성이 증가된다. 이 식물은 액포 내에 중금속을 축적하고 동시에 원형질막에 발현되는 MTP1 유전자의 발현을 특징으로 한다. 결론적으로, 이러한 식물은 식물 정화 응용 분야 및 내성이 증가 된 식물로 사용될 수 있다.

• Journal of Plant Biotechnology
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• 제6권4호
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• pp.259-264
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• 2004

The present study describes the ameliorating effect of $Ca^{++}\;on\;Cd^{++}$ toxicity on the germination, early growth of mungbean seedlings, nitrogen assimilation enzyme. s-nitrate reductase (NR), nitrite reductase (NIR), anti-oxidant enzymes (POD, CAT and SOD) and on the accumulation of hydrogen peroxide and sulphydryls. $Cd^{++}$ inhibited seed germination and root and shoot length of seedlings. While NR activity was down- regulated, the activities of NIR, POD and SOD were up- regulated with $Cd^{++}$ treatment. $Cd^{++}$ treatment also increased the accumulation of sulphydryls and peroxides, which is reflective of increased thiol rich proteins and oxidative stress. $Ca^{++}$ reversed the toxic effects of $Cd^{++}$ on germination and on early growth of seedlings as well as on the enzyme activities, which were in turn differentially inhibited with a combined treatment with calcium specific chelator EGTA. The results indicate that the external application of $Ca^{++}$ may increase the tolerance capacity of plants to environmental pollutants by both up and down regulating metabolic activities. Abbreviations: $Cd^{++}= cadmium,\;Ca^{++} = calcium$, NR= nitrate reductase, NIR=nitrite reductase, POD = peroxidse, SOD= superoxide dismutase, CAT= catalase, EGTA= ethylene glycol-bis( $\beta-aminoethyl ether$)-N,N,N,N-tetraacetic acid.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2001년도 추계학술발표대회
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• pp.177-180
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• 2001

Tobacco plants were transformed by A. tumefaciens harboring human ferritin gene and they were subjected to investigate for the expression of transformed gene as well as heavy metal accumulation. Seed from self-fertilized transgenic plants was germinated on media containing toxic level of Cd, Cu, Zn, Fe, Mn and scored for tolerance to this heavy metals. There is difference in growth rate between transgenic and control plants, especially Cd, Cu. And transgenic plants accumulated more heavy metals than control plants.