• Journal of Plant Biotechnology
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• v.41 no.3
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• pp.146-158
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• 2014

Camelina sativa that belongs to Brassicaceae family is an emerging oilseed crop. Camelina seeds contain approximately 40% storage oils per seed dry weight, which are useful for human and animal diets and industrial applications. Microsomal delta-12 fatty acid desaturase2 (FAD2) catalyzes the conversion of oleic acid to linoleic acid. The polymorphisms of FAD2 genes are correlated with the levels of oleic acids in seed oils. Microsomal delta-12 fatty acid desaturase2 (FAD2) catalyzes the conversion of oleic acid to linoleic acid. The polymorphisms of FAD2 genes are correlated with the levels of oleic acids in seed oils. In this study, three CsFAD2 genes (CsFAD2-1, CsFAD2-2 and CsFAD2-3.1) were isolated from developing seeds of Camelina sativa (L.) cv. CAME. The nucleotide and deduced amino acid sequences of three CsFAD2 genes were compared with those from dicotyledon and monocotyledon plants including Camelina cultivars Sunesone and SRS933. Three histidine motifs (HECGH, HRRHH, and HVAHH) required for FAD activity and a hydrophobic valine or isoleucine residue, which is a SNP (single nucleotide polymorphism) marker related with enzyme activity are well conserved in three CsFAD2s. The expressions of CsFAD2-1 and CsFAD2-3.1 were ubiquitously detected in various Camelina organs, whereas the CsFAD2-2 transcripts were predominantly detected in flowers and developing seeds. The contents of oleic acids decreased, whereas the amounts of linoleic acid increased in dry seeds of transgenic fad2-2 lines expressing each CsFAD2 gene compared with fad2-2 mutant, indicating that three CsFAD2 genes are functionally active. The isolated CsFAD2 genes might be applicable in metabolic engineering of storage oils with high oleic acids in oilseed crops.

• Current Research on Agriculture and Life Sciences
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• v.4
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• pp.55-64
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• 1986

Polyphenol oxidase in japanese pear (Pyrus communis var. mansamkil) was isolated, partially purified and its some properties were investigated. Polyacrylamide disc gel electrophoresis indicated two bands with polyphenol oxidase activity in the extract from acetone dry powder of par flesh. These two polyphenol oxidases (PPO A and PPO B) were purified through acetone precipitation and diethylaminoethyl cellulose column chromatography. PPO A and B were purified 7.8 fold and 8.7 fold by the present procedure, respectively. The Rm values of partially purified PPO A and B were estimated to be 0.58 and 0.68, respectively. The optimum temp, and pH of PPO A activity were $33^{\circ}C$ and pH 7.0, while those of PPO B were $30^{\circ}C$ and pH 4.2, respectively. Two PPO were unstable over the temperature of $60^{\circ}C$. The substrate specificity of pear PPO showed high affinity toward o-diphenolic compounds, especially catechol in PPO A and chlorogenic acid in PPO B, but inactive toward m-diphenol, p-diphenol and monophenols. PPO A showed affinity toward the trihydroxyphenolic compound. $Zn^{{+}{+}}$ activated the PPO A activity but $Fe^{{+}{+}}$ inhibited PPO B activity, while $Fe^{{+}{+}}$ and $Zn^{{+}{+}}$ activated the PPO B activity, while $Fe^{{+}{+}}$ and $Zn^{{+}{+}}$ activated the PPO B activity but $K^+$, $Mg^{{+}{+}}$, $Ca^{{+}{+}}$ and $Hg^{{+}{+}}$ inhibited at 10mM concentration. $Cu^{{+}{+}}$ activated the enzyme action at low concentrations but inhibited at high concentration. Inhibition studies indicated that L-ascorbic acid, L-cysteine and thiourea were most potent. The Km values of PPO A and PPO B for catechol were 20mM and 14.3mM, respectively.

• Korean Journal of Microbiology
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• v.55 no.3
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• pp.234-241
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• 2019

An intensive interaction between yeasts and insects has highlighted their relevance for attraction to food and for the insect's development and behavior. Yeast associated in the gut of insects secretes cellulase which aided in the food digestion (cellulose degradation). Three strains of cellulose-degrading yeast were isolated from the gut of adult grasshoppers collected in Gyeonggi Province, South Korea. The strains $ON22^T$, $G10^T$, and $G15^T$, showed positive cellulolytic activity in the carboxymethyl cellulose (CMC)-plate assay. The phylogenetic tree based on sequence analysis of D1/D2 domains of the large subunit rRNA gene and the internal transcribed spacer (ITS) regions revealed that the strains $ON22^T$ (100 and 98.4% sequence similarities in D1/D2 domains and ITS) and $G10^T$ (99.8 and 99.5% in D1/D2 domain and ITS region) were most closely related to the species Moesziomyces aphidis JCM $10318^T$; $G15^T$ (100% in D1/D2 domains and ITS) belongs to the species Moesziomyces antarcticus JCM $10317^T$, respectively. Morphology and biochemical test results are provided in the species description. Cellulase with its massive applicability has been used in various industrial processes such as biofuels like bioethanol productions. Therefore, this is the first report of the cellulolytic yeast strains $ON22^T$, $G10^T$, and $G15^T$ related to the genus Moesziomyces in the family Ustilaginaceae (Ustilaginales), in Korea.

• The Korean Journal of Pesticide Science
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• v.2 no.3
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• pp.36-44
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• 1998

To develope cost-effective new granular formulation of mixture with 7.0% chlomethoxyfen and 3.5% butachlor, this study was conducted by investigation of floatability, dispersibility or collapsability and released concentration of active ingredients in water and bio-efficacies of the granules formulated by different formulation methods compared to commercial pellet-extruded granules. They were formulated by coating on or impregnation into extruded pellets, sands and zeolites with two active ingredients, binders, friction reducer, dispersing agents and bentonite. Pellet-coated method showed similar floatability, collapsability and bio-efficacy to the commercial pellet-extruded one or better than that but unstable patterns of released concentration of chlomethoxyfen because of easy isolation of coated technical particles from the surface of granules. Sand-coated methods showed similar physical properties, released pattern of two active ingredients, and bio-efficacy to the commercial one. Liquid binders and/or dispersing agents are more important than powdered ones to control released concentration of active ingredients from the granule mixtures, to improve the floatability and dispersibility, and to show good bio-efficacy. Sand-coated one might be a suitable method if types and amount of liquid binders and dispersing agents are selected.

• The Korean Journal of Mycology
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• v.23 no.3 s.74
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• pp.246-256
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• 1995

Phenotypic characteristics, pathogenicity and fungicides resistance of fifty one isolates of Botrytis cinerea obtained from various host plants were observed and determined. The relationships between these characteristics were also investigated on the basis of isolation host plants. The isolates of B. cinerea varied in the capacity of sclerotia formation and sporulation. The pathogenicity of 44 isolates from tomato, cucumber, and strawberry was significantly stronger with 3.2 cm in average diameter of necrotic lesions on cucumber leaves than that of seven isolates from other host plants such as orange, gerbera, ginseng, kiwi, grape, pear and from butter with 1.8 cm in average diameter of necrotic lesions. Benomyl resistance of 12 isolates from tomato plants was much higher with the $EC_{50}$, 562 ppm than that of 19 isolates from various host plants. Diethofencarb resistance, however, of 11 isolates from strawberry plants was highest with the $EC_{50}$, 210 ppm among isolates from other host plants. Polygalacturonase activity varied among isolates in the range of 0 to 103 unit and that of isolates from tomato, cucumber and strawberry was slightly lower than that of isolates from other host plants. No significant relationship between pathogenicity and fungicides resistance, polygalacturonase activity was found among 51 isolates of B. cinerea. Isozyme patterns of polygalacturonase produced from two strongly and weakly pathogenic isolates (FC122, KC6) were slightly different depending upon carbon sources during cultivation.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.11 no.2
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• pp.157-178
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• 2013

This study gives a conceptual and basic direction to develop a URL (underground research laboratory) program for establishing the performance and safety of a deep geological disposal system in Korea. The concept of deep geological disposal is one of the preferred methodologies for the final disposal of spent nuclear fuel (SNF). Advanced countries with radioactive waste disposal have developed their own disposal concepts reasonable to their social and environmental conditions and applied to their commercial projects. Deep geological disposal system is a multi-barrier system generally consisting of an engineered barrier and natural barrier. A disposal facility and its host environment can be relied on a necessary containment and isolation over timescales envisaged as several to tens of thousands of years. A disposal system is not allowed in the commercial stage of the disposal program without a validation and demonstration of the performance and safety of the system. All issues confirming performance and safety of a disposal system include investigation, analysis, assessment, design, construction, operation and closure from planning to closure of the deep geological repository. Advanced countries perform RD&D (research, development & demonstration) programs to validate the performance and safety of a disposal system using a URL facility located at the preferred rock area within their own territories. The results and processes from the URL program contribute to construct technical criteria and guidelines for site selection as well as suitability and safety assessment of the final disposal site. Furthermore, the URL program also plays a decisive role in promoting scientific understanding of the deep geological disposal system for stakeholders, such as the public, regulator, and experts.

• Journal of Advanced Navigation Technology
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• v.21 no.4
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• pp.377-385
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• 2017

The solar cell need the characteristic interpreting because the solar cell changes greatly according to the isolation, temperature and load in the photovoltaic development. Moreover, to get many energy in photovoltaic development need the position tracking of the sun according to the environment change. Also, The solar cells should be operated at the maximum power point. In this paper, I used microprocessor and sensor and designed to improve the efficiency of the photovoltaic system the photovoltaic position tracker device, and compared the normal photovoltaic system of fixed form with the photovoltaic system of solar position tracked form. Moreover, compared the catalogue of solar cell module and the simulation through a mathematics modelling with the solar cell's characteristic interpreting and composed an power conversion system with boost converter and voltage source inverter. Used the constant voltage control method for maximum power point tracking in boost converter control and, used the SPWM(Sinusoidal Pulse Width Modulation) control method in inverter control. The result was less then 5% when compared the catalogue of solar cell module and the simulation through a mathematics modelling. The boost rate of boost converter was similar to 167 % with the simulation.

• Korean Journal of Environmental Biology
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• v.35 no.1
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• pp.57-63
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• 2017

This study was conducted to determined the status and geographical distribution of the alien invasive Red-eared slider (Trachemys scripta elegans) turtle on Jeju Island. We found thirty-two Red-eared slider habitats including twenty-five ponds, five agricultural reservoirs, a puddle and a stream. Among those, thirteen sites are newly determined habitats of the turtle. The remaining nineteen are previously reported. However, we could not find any turtles at nine sites, which were documented as turtle habitats in earlier reports. A total of one hundred thirty-three turtles were observed. Among them, we determined that thirty-nine were juvenile turtles, found in nineteen different habitats, indicating estimating that Red-eared sliders produced their progeny in the wild of this island. Because of geographical isolation by the ocean, no freshwater turtle had been found until $19^{th}$ Century. Therefore, the increased number of finding sites and Red-eared sliders indicate the possibility of human release of their pets or for other purposes, and natural propagation in the wild on Jeju Island. Our findings will be useful for management planning to deal with this invasive species, and implementation of a conservation program for native wildlife on Jeju Island.

• Analytical Science and Technology
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• v.12 no.5
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• pp.428-435
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• 1999

A method for measuring Rn-222 and Ra-226 in aqueous sample using liquid scintillation counting technique has been studied. The Rn-222 was extracted easily from the water sample (10 mL) by 12 mL of xylene based organic scintillant. After radioactive equilibrium between Rn-222 and its alpha emitting decay products for three hours, the alpha activity from Rn-222 and its decay products were measured in a scintillation vial using the Wallae $1220^{TM}$ Quantulus liquid scintillation counter. Ra-226 concentration in aqueous sample was determined, after isolation of Ra-226 from the sample matrix, by extraction the ingrowth of the Rn-222 and its alpha emitting decay products with xylene based organic scintillant. The optimum pulse-shape analysis (PSA) value was evaluated by the figure of merit (FM) criterion. Minimum detectable activity (MDA) is about 0.14 Bq/L (3.78 pCi) for the region of Rn-222 and its alpha emitting decay products and 0.06 Bq/L (1.63 pCi) for the region of Po-214 respectively, with 200 min, counting time at PSA level 100 in the low-diffusion polyethylene vial and xylene based cocktail solution. Experiment on the optimum sample-cocktail volume ratio, the influence of agitation and the diffusion of radon from vial were carried out.

• Journal of Life Science
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• v.15 no.5 s.72
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• pp.679-684
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• 2005

The objective of this study was investigate the characteristic of biosurfactant produced from the iso-lated strain. The strain was isolated from soli samples of Duck-Yu Mountain and it was identified as Bacillus atrophaeus DYL-130 by 16S rDNA and gyrA gene nucleotide sequence analysis. The surface ten-sion of culture filtrate of Bacillus atrophaeus DYL-130 decreased to 28 mN/m and its biosurfactant con-centration was determined by diluting the culture filtrate until the critical micelle concentration (CMC). The emulsifying activity and stability of crude biosurfactant was measured by using water-immiscible hydrocarbons and oils as substrate. The biosurfactant was purified by affinity chromatography and the surface activity of purified biosurfactant was measured by drop-collapsing method and it could be effectively emulsify toluene.