• Molecules and Cells
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• v.23 no.3
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• pp.280-286
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• 2007

L-asparaginase (EC 3.5.1.1) catalyzes the hydrolysis of the amide group of L-asparagine, releasing aspartate and $NH_4{^+}$. We isolated a low temperature-inducible cDNA sequence encoding L-asparaginase from soybean leaves. The full-length L-asparaginase cDNA, designated GmASP1, contains an open reading frame of 1,258 bp coding for a protein of 326 amino acids. Genomic DNA blotting and fluorescence in situ hybridization showed that the soybean genome has two copies of GmASP1. GmASP1 mRNA was induced by low temperature, ABA and NaCl, but not by heat shock or drought stress. E. coli cells expressing recombinant GmASP1 had 3-fold increased L-asparaginase activity. A possible function of L-asparaginase in the early response to low temperature stress is discussed.

• Journal of Radiation Industry
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• v.6 no.2
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• pp.129-138
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• 2012

Proteomic analysis was performed in order to identify proteomic changes by salt stress between the Japonica cv. Donganbyeo (WT) and two salt-tolerant (ST) mutant lines by using the SDS-PAGE and 2-DE. Two salt tolerant rice mutant lines, ST-87 and ST-301, were selected by in vitro mutagenesis with gamma-ray. Three-week-old seedlings were treated with 171 mM NaCl for 7 days. In the SDS-PAGE, three proteins with molecular weights of 27, 46 and 58 kDa were highly increased under salt treatment. Total proteins from shoots of both WT and ST-lines were separated by two-dimensional gel electrophoresis. In 2-DE, 201, 226, 217 and 213 protein spots were detected in the untreated-or treated-WT and untreated- or treated-ST-87, respectively. Of theses, 17 and 10 protein spots were up- and down-regulated under salt stress in the WT, respectively. While, 16 and 8 protein spots were up- and down-regulated under salt stress in the ST-87, respectively, compared with the untreated plants. High intensity or de novo synthesized proteins were analyzed by MALDI-TOF/MS analysis.

• Asian Journal of Turfgrass Science
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• v.11 no.4
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• pp.311-320
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• 1997

This study was carried out to induce and maintain callus from 59 zoysiagrass lines, to know the effective disinfestation method for zoysiagrass stolon as explant and the difference in the response of callus induction among 59 lines, and to investigate the effect of medium, growth regulators, light, temperature, stolon part and internode position on callus induction and emhryogenic callus(E.C.) formation. The treatment of 0.lmg/L $HgCl_2$for 15 min resulted in no contamination and the highest callus induction(46.6%). Callus was induced from the 59 zoysiagrass lines. The callus growth of Z. japonica and Z. sinica was generally better than Z. matrella Ten cell lines whose callus and stolon grow fast in culture and in field, respectively were selected to he used for breeding. Callus induction was the most effective at 2.0mg /L of both 2, 4-D and picloram in MS medium. MS medium was the best for callus induction and growth while LS medium was the best for embryogenic callus and shoot formation. Callus induction and growth was better at 28, 31$^{\circ}C$. than 25$^{\circ}C$. and dark condition was better than light condition in MS me-dium containing 2mg/L 2,4-D. While callus induction was better with node part as explant than with internode part, callus growth and embryogenic callus formation was better with internode part. In 'Japonica 1', the first internode was the most effective in callus induction, but third internode was the best in '$M_2$ X $S_2$'.

• Archives of Pharmacal Research
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• v.27 no.7
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• pp.806-810
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• 2004

Metformin is a biguanide antihyperglycemic agent often used for the treatment of non-insulin dependent diabetics (NIDDM). In this study, the pharmacokinetics and pharmacodynamics of metformin were investigated in Korean healthy volunteers during a fasting state for over 10 h. In order to evaluate the amount of glucose-lowering effect of metformin, the plasma concentrations of glucose were measured for a period of 10 h followed by the administration of metformin (oral 500 mg) or placebo. In addition, the concentration of metformin in blood samples was determined by HPLC assay for the drug. All volunteers were consumed with 12 g of white sugar 10 minutes after drug intake to maintain initial plasma glucose concentration. The time courses of the plasma concentration of metformin and the glucose-lowering effect were analyzed by nonlinear regression analysis. The estimated $C_{max}$, $T_{max}$, $CL_{t}$/F (apparent clearance), V/F(apparent volume of distribution), and half-life of metformin were 1.42$\{pm}$0.07 $\mu\textrm{g}$/mL, 2.59$\{pm}$0.18h, 66.12$\{pm}$4.6 L/h, 26.63 L, and 1.54 h respectively. Since a significant counterclock-wise hysteresis was found for the metformin concentration in the plasma-effect relationship, indirect response model was used to evaluate pharmacodynamic parameters for metformin. The mean concentration at half-maximum inhibition $IC_{50}$, $k_{in}$, $k_{out}$ were 2.26 $\mu\textrm{g}$/mL, 83.26 $H^{-1}$, and 0.68 $H^{-1}$, respectively. Therefore, the pharmacokinetic-pharmacodynamic model may be useful in the description for the relationship between plasma concentration of metformin and its glucose-lowering effect.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.4
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• pp.212-219
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• 2021

Chemical accidents caused by transport vehicles account for 20% of all chemical accidents every year, but there are difficulties in the accident-response process due to repeated situations where the impact assessment information is unknown. In this study, we developed a calculation table and formula for predicting the range of damage for chlorine and hydrogen fluoride, which have a high domestic usage, high risk of accidents, and high accident frequency in the last 7 years. The calculation table is based on the leakage rate, wind speed, and temperature, and the calculation formula was derived using R software for special situations where it is difficult to apply the calculation table. The calculation table and formula could be used on site by related organizations to obtain important information for decision making, which could help in minimizing damage from chemical accidents, setting separation distances, and deciding to evacuate residents.

• Journal of Medicine and Life Science
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• v.15 no.2
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• pp.67-71
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• 2018

Neuronal excitotoxicity induces mitochondrial dysfunction and the release of proapoptotic proteins. Excitotoxicity, the process by which the overactivation of excitatory neurotransmitter receptors leads to neuronal cell death. Neuronal death by excitotoxicity was related to neuronal degenerative disorders and hypoxia, results from excessive exposure to excitatory neurotransmitters, such as glutamate. Glutamate acts at NMDA receptors in cultured neurons to increase the intracellular free calcium concentration. Therefore endogenous glutamate may be a key factor to regulate neuronal cell death via activating $Ca^{2+}$ signaling. For this issue, we tested some conditions to alter intracellular $Ca^{2+}$ level in dissociated hippocampal neurons of rats. Cultured hippocampal neuron were treated by KCl (20 mM), $CaCl_2$ (3.8 mM) and glutamate ($5{\mu}M$) for 24 hrs. Interestingly, The Optical Density of hippocampal neurons was increased by high KCl application in MTT assay data. This enhanced response by high KCl was dependent on synaptic $Ca^{2+}$ influx but not on intracellular $Ca^{2+}$ level. However, the number of neurons seemed to be not changed in Hoechst 33342 staining data. These results suggest that enhancement of synaptic activity plays a key role to increase mitochondrial signaling in hippocampal neurons.

• Journal of Microbiology and Biotechnology
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• v.32 no.1
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• pp.99-109
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• 2022

This study is the first report on production and characterization of the enzyme from an Ornithinibacillus species. A 4.2-fold increase in the extracellular protease (called L9^T) production from Ornithinibacillus caprae L9^T was achieved through the one-factor-at-a-time approach and response surface methodological optimization. L9^T protease exhibited a unique protein band with a mass of 25.9 kDa upon sodium dodecyl sulfate-polyacrylamide gel electrophoresis. This novel protease was active over a range of pH (4-13), temperatures (30-80℃) and salt concentrations (0-220 g/l), with the maximal activity observed at pH 7, 70℃ and 20 g/l NaCl. Proteolytic activity was upgraded in the presence of Ag⁺, Ca²⁺ and Sr²⁺, but was totally suppressed by 5 mM phenylmethylsulfonyl fluoride, which suggests that this enzyme belongs to the serine protease family. L9^T protease was resistant to certain common organic solvents and surfactants; particularly, 5 mM Tween 20 and Tween 80 improved the activity by 63 and 15%, respectively. More importantly, L9^T protease was found to be effective in dehairing of goatskins, cowhides and rabbit-skins without damaging the collagen fibers. These properties confirm the feasibility of L9^T protease in industrial applications, especially in leather processing.

• Journal of Environmental Science International
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• v.30 no.11
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• pp.957-965
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• 2021

This research was carried out to investigate seed germination and growth of the perennial plant Apocynum lancifolium under different NaCl concentrations, with a view for future cultivation on reclaimed land. Initial characterization revealed that the average length and weight of A. lancifolium seed pods was 133.6 mm and 0.23 g, respectively, and the thousand-grain weight was 0.59 g. Upon examining the effects of light on seed germination, we found germination to be 1.7% higher under light conditions (90%) than under dark conditions (88.3%). In terms of the response to salt stress, we found that 90% of seeds germinated in the 0.00%, 0.25%, and 0.50% salt treatment groups. Although salt treatment up to a concentration of 0.5% was found to have little effect on seed germination, the rate of germination decreased at higher concentrations and was completely inhibited in the 2% treatment. We also established that germination rates were higher in seeds sown in horticultural topsoil than in the coarse sandy soil found in the plant's natural habitats. Although the growth of A. lancifolium tends to decrease with an increase in salt concentration, we found that the stem thickness, fresh weight, and dry weight of A. lancifolium seedlings subjected to 0.25%-1.0% salt were comparable to those of the control seedling that were not exposed to salt. Furthermore, in contrast to those plants subjected to 2.0% salt, these plants continued to grow and remained viable.

• Corrosion Science and Technology
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• v.22 no.1
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• pp.21-29
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• 2023

In this paper, a SiC nano electroless nickel plating layer with excellent corrosion resistance was fabricated using the Taguchi method. The electroless plated low carbon steel was subjected to tests to examine the influence of corrosive media, microhardness, and corrosion rate on the corrosion resistance of this alloy. Three different corrosive media (HCl, Na₂SO₄, and NaCl) at various temperatures (80, 90, and 100 ℃) were used, and at three different times (40, 80, and 120 min.) with a speed of stirring equal to 500 rpm. The results of microhardness were found from 134.276 HV to 278.578 HV at various conditions, while the corrosion rate results were obtained from 0.89643 mpy to 7.12571 mpy at different circumstances. Corrosion, and mechanical characteristics were explained using Taguchi design. Taguchi technique was used to account for all possible combinations of elements in order to conduct a complete study. Models that link the response and procedure parameters were developed using the results of these tests, and the analysis of variance was utilized to validate these models (ANOVA). For maximum efficiency, a function called "desirability" was applied to all responses at once.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.113-113
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• 2022

Salinity in surface waters is increasing around the world. Many factors, including increased water extraction, poor irrigation management, and sea-level rise, contribute to this change, and posing a threat to plant development and agricultural production. Seeds exposed to high salinity, have a lower probability of germinating and various physiological and biochemical effects. Salinity stress affects more than 20% of agricultural land and about 50% of irrigated land. In the current study, our objective is to identify the salt-tolerant peanut (Arachis hypogaea L.) Korean genotypes under salinity stress. Thus, two-week-old 19 diverse peanut Korean genotypes were exposed to 10 days of salinity (150 mM NaCl) stress. Based on the growth attributes investigation, Baekjung and Ahwon genotypes showed significantly higher shoot lengths compared to control plants. Whereas, the Sinpalwang genotype exhibited a significantly positive response for plant growth and reduced wilting symptoms compared to other genotypes. This study was able to find out peanut tolerant and sensitive genotypes for salt stress. These results may provide a good template for further salt-tolerant peanut cultivar improvement programs. Identified diverse salt-responsive genotypes can be utilized as source material in Korean breeding schemes for peanut crop improvement for salt and other abiotic stress tolerance.