• Microbiology and Biotechnology Letters
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• v.27 no.5
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• pp.378-384
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• 1999

Protopectinase (PPases) are heterologous group of enzymes that degrade pectin from the insoluble protopection which is constituent of the middle lamella and primary cell wall of higher plants by restricted depolymerization. From the previous report[6], enzymatically separated plant cells, which are produced from plant tissues by PPases treatment, showed well-conserved cellular components with their rigid cell wall and this characteristic is applicable to preparation of novel food material. The purpose of this study is to investigate the effect of medium composition of PPase production from Bacillus subtilis EK11 which was selected as a PPase producer. Various carbon sources and concentrations on PPase production were studied and corn starch at 0.7% was the most effective for production of PPase. Among the nitrogen sources, yeast extract was the most effective for PPase production and the effect of (NH4)2SO4 was notable as inotganic nitrogen source. Inorganic compounds such as KH2PO4, K2HPO4, Na3-citrate.2H2O and MgSO4 were optimized for PPase production. PPase activity was inhibited by the adition of Ba2+ or Zn2+. The optimal medium for PPase production was devised: 0.7% corn starch, 0.3% yeast extract, 1.4% KH2PO4, 0.6% K2HPO4, 0.1% Na3-citrate.2H2O and 0.02% MgSO4. PPase production by using the optimum medium was carried out with shaking cultivation at 37$^{\circ}C$. The maximum PPase activity of 256unit/ml could be obtained after the cultivation for 48hrs. The activity was increased about 2.2timesthan the activity, 112 unit/ml, in basal medium.

• Journal of the Korean Institute of Landscape Architecture
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• v.35 no.6
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• pp.48-63
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• 2008

This research is to apply suitable natural ecosystem evaluation criteria in order to develop the ecosystem conservation, restoration and ways to build substitute habitats as a compensation plan for damaged soundly natural ecosystems in small-scale projects such as resource recovery facility, filtration, etc. The environmental ecology evaluation i.e. generally based on their actual vegetation, community structure, wildlife, water system survey were measured the primary plans for reflecting unique natural environment level of site. As a result, it is necessary to conserve the land in fallow type of wetland, good conservative condition of deciduous forest, wetlanded watercourse for amphibia and reptiles crossing. However, the plan of filtration plant was destroyed wetland(sound ecosystem), natural forest, asian toad spawning area. According to the result of it schemed to build alternative wetland and spawning area, plan to healthy ecosystem and surface soil transplantation as compensation plan. The alternative wetland and spawning area are not only created a various water levels like depth of water is $0{\sim}30cm,\;30{\sim}60cm$, more than 1.5m but also it leads to asian toad spawning and wildlife inhabitant. Moreover, the ecosystem and surface soil transplantation be applied to use the Quercus acutissima forest resources(114 upper trees, 71 canopy trees, 401 shrubs) and surface soil$(5,072m^3)$ in ecology creation sets.

• Proceedings of the Korean Society of Plant Biotechnology Conference
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• 2004.10a
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• pp.74-79
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• 2004

Little is known about the effect of epigallocatechin-3 gallate (ESCG), a major constituent of green tea, on the expression of cyclooxygenase (COX)-2. Here, we studied the role of phospholipase D (PLD) isozymes in EGCG-induced COX-2 expression. Stimulation of human astrocytoma cells (U87) with EGCG induced formation of phosphatidylbutanol, a specific product of PLD activity, and synthesis of COX-2protein and its product, prostaglandin $E_2$ ($PGE_2$). Pretreatment of cells with 1-butanol, but not 3-butanol, suppressed EGCG-induced COX-2 expression and $PGE_2$ synthesis. Furthermore, evidence that PLD was involved in EGCG-induced COX-2 expression w3s provided by the observations that COX-2 expression was stimulated by over-expression of PLD1 or PLD2 isozymes and treatment with phosphatidic acid(PA), and that prevention of PA dephosphorylation by 1-propranolol significantly potentiated COX-2expression Induced by EGCG. EGCG induced activation of p38 mitogen-activated protein kinase (p38MAPK), and specific Inhibition of p38 MAPK dramatically abolished EGCG-Induced PLD activation, COX-2 expression, and $PGE_2$ formation. Moreover, protein kinase C (PKC) inhibition suppressed EGCG-induced p38 MAPK activation, COX-2 expression, and $PGE_2$ accumulation. The same pathways as those obtained in the astrocytoma cells were active in primary rat astrocytes, suggesting the relevance of the findings. Collectively, our results demonstrate for the first time that PLD isozymes mediate EGCG-induced COX-2 expression through PKC and p38 in immortalized astroglial line and normal astrocyte cells.

• The Plant Pathology Journal
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• v.17 no.1
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• pp.36-39
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• 2001

The secondary effects of pencycuron on cell membrane of Rhizoctonia solani AG4 were investigated by the observation of giant protoplast formation and lipid peroxidation. Compared to protoplasts of R. solani R-C (sensitive strain) and Rh-131 (non-sensitive strain) increased in their size by 2.0-3.5 times 12 h after incubation in potato-dextrose broth containing novozyme (7 mg/$m\ell$) and $\beta$-glucuronidase ($60\mu\textrm{g}/$\textrm{ml}) with 0.6 M mannitol (pH 5.2). The increase of protoplast size in R-C was slightly inhibited from $13.8\textrm{mg}/\textrm{ml}$ without pencycuron to 10.3 ${\mu}{\textrm}{m}$ with 1.0$\mu\textrm{g}$/$m\ell$ of pencycuron. However, the size of giant protoplast of Rh-131 was not affected by the pencycuron treatment. Both strains R-C and Rh-131 did not exhibit the lipid peroxidation 12 h after the application of 1.0 $\mu\textrm{g}$/$m\ell$ pencycuron. The remarkable peroxidation of membrane lipid was observed only in R-C 24 h after pencycuron application, but not in Rh-131. Althought the inhibition of giant protoplast formation and the membrane lipid peroxidation were observed only in the sensitive strain R-C by pencycuron, it is difficult to conclude that these are the primary mechanism of pencycuron. The mild activity of pencycuron on the inhibition of giant protoplast formation and late membrane lipid peroxidation in the fungicide-sensitive strain did not noincid with the dramatic activity of pencycuron in R. solani. Therefore, our results suggest that inhibition of giant protoplast formation and membrane lipid peroxidation is the secondary effect of pencycuron.

• FLOWER RESEARCH JOURNAL
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• v.17 no.3
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• pp.185-189
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• 2009

This study was carried out to investigate the effect of shading (50% or not) and pruning height (3cm, 6cm, and 9cm) of remained above-ground plant part on shoot emergence aspect, mortality rate, flowering and cut flower characteristics of two years old Gypsophila paniculata plants. Days to shoot emergence (80%) advanced, emerged shoot number increased and mortality rate surveyed on late October decreased in 50% shading treatment. In addition to, mortality rate decreased, as above-ground plant part was highly pruned. Blooming was earlier with highly pruning the remained above-ground pan and under non-shading condition than shading. Growth traits such flower stalk length, primary branches number, stem diameter, and cut flower yield were the best and also non-particulate rate and rosette formation rate were the lowest in pruning height of 9cm under non-shading condition.

• Journal of Plant Biology
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• v.38 no.4
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• pp.373-380
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• 1995

Photoinhibition of photosystem (PS) n was induced in primary leaves of 25 day-old peppers grown $100\;{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1},\;at\;25^{\circ}C$. The modulation of PSII functionality in vivo was induced by varying both irradiance ($0-3000\;{\mu}molm^{-2}{\cdot}s^{-1}$) and duration (0-70 min) of light treatment. The functionality of PSII was investigated in terms of photochemical efficiency of PSII (Fv/Fm) and quantum yield of $O_2$ evolution, and expressed as a function of photon exposure [$mol\;photons{\cdot}m^{-2}$, the product of irradiance and duration of light treatment (Bell and Rose, 1981)]. Contrary to the linear decline of Fv/Fm ratio showing 50% decreases by absorption of $10\;mol\;photons{\cdot}m^{-2$, quantum yield of $O_2$ evolution decreased biphasically with increasing photon exposure, showing 50% decreases by absorption of $5.5\;mol\;photons{\cdot}m^{-2}$. Treatment of low temperature at $15^{\circ}C$ for 30 min alone did not affect the functionality of PSII, but high temperature ($45^{\circ}C$) significantly inactivated PSII activity. However, when Jeaves of pepper were subjected to low or high temperature in the presence of light, PSII was substantially photoinactivated. These results suggest the presence of different photoinhibitory mechanisms at low and high temperature.rature.

• Journal of Plant Biotechnology
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• v.32 no.4
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• pp.293-300
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• 2005

The possible role of nitric oxide (NO)-induced cell division was investigated to explain the physiologycal effects of a NO donor, sodium nitroprusside (SNP) on the growth of primary leaves in chinese cabbage seedling plants. Exogenous treatment of SNP to chinese cabbage plants for 8 days at different concentrations (0, 200, 500 and 1000 ${\mu}M$) affected the leaf growth in a concentration-dependent manner, showing a maximum growth at $200\;{\mu}M$. In accordance with leaf growth responses, the chlorophyll and soluble protein contents increased strongly to 142% and 134% of control at $200\;{\mu}M$ SNP, respectively. However, a very little decrease in chlorophyll and a 13%> decrease in protein were observed at $1000\;{\mu}M$ SNP. In addition, the content of DNA and RNA also increased maximumly to 142% and 139% of the control at $200\;{\mu}M$ SNP, respectively, whereas they decreased to 80% and 84% of the control at $1000\;{\mu}M$ SNP. With respect to the development of enzymes related to cell wall synthesis, $200\;{\mu}M$ SNP led to the maximum activities in both phenylalanine ammonia-lyase (212% of the control) and guaiacol peroxidase (134% of the control). However, the activities of both enzymes were not modified significantly at $1000\;{\mu}M$ SNP. In conclusion, these results suggest that the enhancement of leaf growth in chinese cabbage plants by SNP at the effective concentration was probably due to the NO ability in the induction of cell division.

• Korean Journal of Plant Resources
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• v.9 no.3
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• pp.285-290
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• 1996

This experiment was conducted to investigate the variation of adhering primary and secondary rachis branches of panicle in three ecotypes at National Honam Agricultural Experiment Station in 1993. Three ecotypes. Odaebyeo and Sinunbongbyeo as early-maturing type, Cheongmyeongbyeo and Changanbyeo as medium, and Dongjinbyeo and Mangeumbyeo as late-maturing type were used. The treatment were 5 planting times from May 5 to 5 July by 15 day intervals. The number of primary rachis branch in early maturing type recorded high in between May 5 and 20 May as early transplanting. Medium and late-maturing type, however, was found to be have more primary rachis branches at the late time of June 20 transplanting than at the optimum transplanting of Honam area. The number of secondary rachis branch was high between June 5 and 20 June regardless ecotypes. The rate of secondary rachis branch per primary rachis branch was increased with later transplanting time up to June 5, but showed no differences onwards. The number of grain in primary and secondary rachis branches were low in transplanting time of May 5 regardless ecotype but high in late transplanting time by July 5. Densinty of seed sets was found to be higher in late transplanting than in early transplating;early-maturing type showed high in July 5 and 20 June in medium-late maturing type respectively.

• Korean Journal of Soil Science and Fertilizer
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• v.46 no.5
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• pp.351-358
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• 2013

A suitable supply of mineral elements into shoot via a root system from growth media makes plants favorable growth and yield. The shortage or surplus of minerals directly affects overall physiological reactions to plants and, especially, strongly influences carbohydrate metabolism as a primary response. We have studied mineral uptake and synthesis and translocation of soluble carbohydrates in N, P or K-deficient tomato plants, and examined the interaction between soluble carbohydrates and mineral elements. Four-weeks-old tomato plants were grown in a hydroponic growth container adjusted with suboptimal N ($0.5mmol\;L^{-1}\;Ca(NO_3)2{\cdot}4H_2O$ and $0.5mmol\;L^{-1}\;KNO_3$), P ($0.05mmol\;L^{-1}\;KH_2PO_4$), and K ($0.5mmol\;L^{-1}\;KNO_3$) for 30 days. The deficiency of specific mineral element led to a significant decrease in its concentration and affected the concentration of other elements with increasing treatment period. The appearance of the reduction, however, differed slightly between elements. The ratios of N uptake of each treatment to that in NPK sufficient tomato shoots were 4 (N deficient), 50 (P deficient), and 50% (K deficient). The P uptake ratios were 21 (N deficient), 19 (P deficient), and 28% (K deficient) and K uptake ratios were 11 (N deficient), 46 (P deficient), and 7% (K deficient). The deficiency of mineral elements also influenced on carbohydrate metabolism; soluble sugar and starch was substantially enhanced, especially in N or K deficiency. In conclusion, mineral deficiency leads to an adverse carbohydrate metabolism such as immoderate accumulation and restricted translocation as well as reduced mineral uptake and thus results in the reduced plant growth.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.16 no.3
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• pp.377-387
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• 2018

Korea's first commercial nuclear power plant, Kori Unit 1, was permanently shut down on June 18, 2017, after 40 years of successful operation. Kori Unit 1 plans to construct a waste treatment facility in the turbine building prior to commencement of dismantling in earnest. Various radioactive wastes are decontaminated, disassembled, cut and melted in the waste treatment facility and sent to the radioactive waste repository. The proportion of metal radioactive waste in dismantled waste is about 70%, of which large metal radioactive waste is mainly generated in the primary circuit and has high radioactivity, so radiation exposure must be managed during disassembly. In this study, the steam generators are selected as large metal radioactive waste, the exposure doses of the dismantling workers are calculated using RESRAD-RECYCLE code and the methods for reducing the exposure doses are suggested.