• Korean Journal of Microbiology
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• v.45 no.2
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• pp.193-199
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• 2009

A bacterium producing the halotolerant extracellular protease was isolated from squid jeotgal, and was identified as Bacillus sp. SJ-10 based on morphological, physiological and biochemical characteristics, as well as phylogenetic analysis using 16S rRNA gene sequence. The strain grew at $20^{\circ}C\sim55^{\circ}C$, pH 5~8, and 0%~14% NaCl and optimal growth conditions were $35{\pm}5^{\circ}C$, pH 7, and 5% NaCl. The major cellular fatty acids were anteiso-$C_{15:0}$, anteiso-$C_{17:0}$, and $C_{16:0}$ DNA G+C content was 50.58 mol% and menaquinone consisted of MK-7 Phylogenic analysis based on the 16S rRNA gene sequence indicated that SJ-10T belongs to the genus Bacillus. About 40 kDa of the salt-tolerant protease was purified by 40% ammonium sulfate saturation and Mono Q column chromatography. The optimal activity of the protease was pH 8 and stable at pH 5~10. The optimum temperature and NaCl concentration were $35{\pm}5^{\circ}C$ and $5{\pm}1%$, respectively.

• Journal of Korean Society for Atmospheric Environment
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• v.20 no.3
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• pp.381-396
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• 2004

In order to understand the precipitation acidity and chemical composition of ion species in Iksan area as well as to know the difference of chemical characteristics in precipitation samples from the viewpoint of precipitation sampling method, precipitation samples were collected by wet-only automatic precipitation sampler and bulk manual precipitation sampler in Iksan, from March 2003 to August 2003. The mean pH of precipitation was 5.0. There was a little significant difference in the mean value of pH between automatic and manual sampler. However, pH values of some precipitation samples were lower in automatic sampler than in manual sampler, especially in case of precipitation samples with small rainfall for March 2003. The mean concentrations of each ions in precipitation were generally a little higher in precipitation samples collected by the manual sampler than in those collected by the automatic sampler because of accumulation of dry deposition on the surface of glass funnel installed at the manual sampler during the sampling period or no rainfall. Dominant species determining the acidity of precipitation, were N $H_4$$^{[-10]}$ and nss-C $a^{2+}$ for cations and nss-S $O_4$$^{2-}$ and N $O_3$$^{[-10]}$ for anions. The mean concentration of N $H_4$$^{+}$ and nss-C $a^{2+}$ were 31 $\mu$eq/L and 9 $\mu$eq/L for the automatic sampler and 40 ueq/L and 16 ueq/L for the manual sampler, respectively. In addition, nss-S $O_4$$^{2-}$ and N $O_3$$^{[-10]}$ were 27 $\mu$eq/L and 13 $\mu$eq/L for the automatic sampler and 32 $\mu$eq/L and 17 $\mu$eq/L for the manual sampler, respectively. Although the concentrations of the acidifying ions of nss-S $O_4$$^{2-}$ and N $O_3$$^{[-10]}$ were about 3 times higher than those for foreign pristine sites, precipitation acidity were estimated to be natural due to the neutralization reaction of the alkaline species of N $H_4$$^{+}$ and nss-C $a^{2+}$ with its higher concentrations. Considering the ratios of nss-S $O_4$$^{2-}$/N $O_4$$^{[-10]}$ nss-S $O_4$$^{2-}$, it was found that ammonium sulphate was dominant in Iksan precipitation. The major non-sea salt ions were maximum concentrations for March, but decreased with increasing of precipitation amount.on amount.

• Food Science of Animal Resources
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• v.26 no.1
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• pp.98-105
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• 2006

This study was performed to investigate the product characteristics of meat products sold in Korean markets and determine if these products meet the comsumer demands. The total nineteen meat produce were evaluated the physico-chemical, textural properties, and microbial counts of total bacteria and Enterobacteriaceae. pH values were ranged from 5.46 to 6.69, moisture $47.6{\sim}65.3%,\;fat\;14.2{\sim}34.7%,\;and\;9{\sim}20%$ and the pH values of ham products were higher than those of sausages. Purge loss(%) and expressible moisture(%) were ranged $2.40{\sim}7.44\;and\;6.10{\sim}21.2%$ respectively. Varied hunter color values (Lightness $59.6{\sim}75.7$, Redness $11.6{\sim}21.1$, Yellowness $2.30{\sim}l1.4$) were observed. Texture profile analysis values were observed and Frank A sausages made with chicken had highest fracturability, hardness and springiness, whereas loin ham and beershinken had highest cohesiveness, gumminess and chewiness. Most meat products had the total microbial counts of less than 3 log CFU/g and Enterbacteriaceae were not detected (< 2 log CFU/g) in this study. These data suggested that the meat products sold in Korean market were various and relatively safe. In addition, well-being meat products, such as low-fat, salt and containing functional ingredient, should be developed to meet the consumer needs these days.

• Korean Journal of Soil Science and Fertilizer
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• v.41 no.1
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• pp.18-25
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• 2008

Pseudomonas sp. PRGB06, a bacterial strain isolated from diamondback moth (Plutella xylostella) gut, was examined for its plant growth promotion and biofertilizing traits. The bacteria growth was observed under various conditions of carbon sources, temperature, pH and salt concentrations. In addition, the mechanisms of antagonism and phosphate solubilization were investigated. The bacterial strain PRGB06, grew well using most of the tested carbon sources. The best growth was observed at $30^{\circ}C$ and pH 7. The inhibition of the pathogenic fungi was likely due to the volatile antifungal metabolite and ammonia gas produced by the bacteria. A significant positive relationship was found between the phosphate solubilization and acid production. When inoculated with PRGB06 in vitro and in gnotobiotic condition, red pepper and maize showed increase in root length, seedling vigor and dry bio-mass.

• Journal of Korea Water Resources Association
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• v.48 no.12
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• pp.1023-1035
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• 2015

This study applies 3-D N-S solver based on PBM (Porous Body Model), LED-WASS-3D ver 2.0 to directly analyze non-linear interaction of seawater-freshwater-coastal aquifer in order to simulate the seawater infiltration into coastal aquifer. This numerical simulation is the first trial in Korea, as well as unusual and new numerical analysis abroad. Firstly, to validate the applied numerical model, the validity and effectiveness was verified for the numerical model by comparing and considering it with the result of laboratory experiment for seawater-freshwater interface in coastal aquifer. And then it simulated the seawater infiltration into coastal aquifer considering the changed levels of seawater and groundwater in order to analyze the distribution characteristics of flow field and seawater-freshwater interface of coastal aquifer as the level difference between seawater and groundwater and rate of seawater level (${\Delta}h/h$) increased. In addition, the characteristics of seawater infiltration were analyzed from the vertical salinity in the coastal aquifer by ${\Delta}h/h$, which cannot be obtained from existing non-diffusion numerical models. Finally, it analyzed the effect of ${\Delta}h/h$ on the seawater infiltration distance in coastal aquifer, which was indexed.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.347-347
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• 2012

Nickel Oxide (NiO) is a transition metal oxide of the rock salt structure that has a wide band gap of 3.5 eV. It has a variety of specialized applications due to its excellent chemical stability, optical, electrical and magnetic properties. In this study, we concentrated on the application of NiO thin film for transparent conducting oxide. The energy band structure, electronic and optical properties of Nickel Oxide (NiO) thin films grown on Si by using electron beam evaporation were investigated by X-Ray Photoelectron Spectroscopy (XPS), Reflection Electron Energy Loss Spectroscopy (REELS), and UV-Spectrometer. The band gap of NiO thin films determined by REELS spectra was 3.53 eV for the primary energies of 1.5 keV. The valence-band offset (VBO) of NiO thin films investigated by XPS was 3.88 eV and the conduction-band offset (CBO) was 1.59 eV. The UV-spectra analysis showed that the optical transmittance of the NiO thin film was 84% in the visible light region within an error of ${\pm}1%$ and the optical band gap for indirect band gap was 3.53 eV which is well agreement with estimated by REELS. The dielectric function was determined using the REELS spectra in conjunction with the Quantitative Analysis of Electron Energy Loss Spectra (QUEELS)-${\varepsilon}({\kappa},{\omega})$-REELS software. The Energy Loss Function (ELF) appeared at 4.8, 8.2, 22.5, 38.6, and 67.0 eV. The results are in good agreement with the previous study [1]. The transmission coefficient of NiO thin films calculated by QUEELS-REELS was 85% in the visible region, we confirmed that the optical transmittance values obtained with UV-Spectrometer is the same as that of estimated from QUEELS-${\varepsilon}({\kappa},{\omega})$-REELS within uncertainty. The inelastic mean free path (IMFP) estimated from QUEELS-${\varepsilon}({\kappa},{\omega})$-REELS is consistent with the IMFP values determined by the Tanuma-Powell Penn (TPP2M) formula [2]. Our results showed that the IMFP of NiO thin films was increased with increasing primary energies. The quantitative analysis of REELS provides us with a straightforward way to determine the electronic and optical properties of transparent thin film materials.

• Journal of Pharmacopuncture
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• v.20 no.1
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• pp.52-56
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• 2017

Objectives: Neutrophils represent the front line of human defense against infections. Immediately after stimulation, neutrophilic enzymes are activated and produce toxic mediators such as pro-inflammatory cytokines, nitric oxide (NO) and myeloperoxidase (MPO). These mediators can be toxic not only to infectious agents but also to host tissues. Because flavonoids exhibit antioxidant and anti-inflammatory effects, they are subjects of interest for pharmacological modulation of inflammation. In the present study, the effects of rutin on stimulus-induced NO and tumor necrosis factor $(TNF)-{\alpha}$ productions and MPO activity in human neutrophils were investigated. Methods: Human peripheral blood neutrophils were isolated using Ficoll-Hypaque density gradient centrifugation coupled with dextran T500 sedimentation. The cell preparations containing > 98% granulocytes were determined by morphological examination through Giemsa staining. Neutrophils were cultured in complete Roswell Park Memorial Institute (RPMI) medium, pre-incubated with or without rutin ($25{\mu}M$) for 45 minutes, and stimulated with phorbol 12-myristate 13-acetate (PMA). Then, the $TNF-{\alpha}$, NO and MPO productions were analyzed using enzyme-linked immunosorbent assay (ELISA), Griess Reagent, and MPO assay kits, respectively. Also, the viability of human neutrophils was assessed using tetrazolium salt 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT), and neutrophils were treated with various concentrations of rutin ($1-100{\mu}M$), after which MTT was appended and incubated at $37^{\circ}C$ for 4 hour. Results: Rutin at concentrations up to $100{\mu}M$ did not affect neutrophil viability during the 4-hour incubation period. Rutin significantly decreased the NO and $TNF-{\alpha}$ productions in human peripheral blood neutrophils compared to PMA-control cells (P < 0.001). Also, MPO activity was significantly reduced by rutin (P < 0.001). Conclusion: In this in vitro study, rutin had an anti-inflammatory effect due to its inhibiting NO and $TNF-{\alpha}$ productions, as well as MPO activity, in activated human neutrophils. Treatment with rutin may be considered as a therapeutic strategy for neutrophil-mediated inflammatory/autoimmune diseases.

• Journal of the Korea institute for structural maintenance and inspection
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• v.21 no.6
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• pp.132-139
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• 2017

A huge amount of de-icing agent is sprayed during winter to promote traffic safety in cold regions, and the quantity of de-icing agent sprayed has increased each year. The main ingredients in commonly used de-icing agents are chlorides, such as calcium chloride($CaCl_2$) and sodium chloride(NaCl). While calcium chloride is mostly used in Korea and sodium chloride is usually used in the U.S. and Japan, all de-icing agents include chloride ions. The chlorides included in sprayed calcium chloride-based de-icing agents have severe adverse effects, including the corrosion of reinforcing steels through salt damage by infiltrating into road structures, reduced structural performance of pavement or damage to bridge structures, and surface scaling, in combination with freezing damage in winter, as well as water pollution. In addition, the deterioration of paved concrete road surface that occurs after the use of calcium chloride-based de-icing agent accelerates the development of visual problems with traffic structures. Therefore, the present study was performed to prepare an environment-friendly liquid de-icing agent through a reaction between waste organic acids and calcium-based by-products, which are industrial by-products, and to analyze the properties of the de-icing agent in order to evaluate its applicability to road facilities.

• Korean Journal of Food Science and Technology
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• v.22 no.7
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• pp.724-731
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• 1990

The fermentation process of Andong Sickhae including optimal composition of the product was investigated. Through sensory evaluation and ingredient analysis of ten samples prepared in the laboratory and the samples collected from Andong region, we found that the ratio of ingredient of the product by weigh are as follow : [glutinous rice(80) : malt(50) : radish(100) : water(500) : ginger(8) : red pepper(4)]. The level of nitrogen compound turned out to be low while that of soluble protein and salt soluble protein was high. The content of total sugar and reducing sugar was found to be considerable high and among the free sugar, maltose was the highest(80%), followed by glucose and maltotriose. Activities of acid protease and saccharogenic amylase were 1.55 unit per milliliter and $12.5D^{40}_{30}^{\circ}$ respectively. Results of sensory evaluation showed that the good Andong Sickhae turned out to have well harmonized taste of flavor, sweetness and sourness while the color looked slightly red.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.43 no.5
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• pp.415-420
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• 2010

In Korea, oysters are used as an ingredient of Kimchi (Korean pickled cabbage) in early winter. Although viral contamination of oysters, including contamination by norovirus, can provoke gastroenteric illness, little is known of the epidemiological relationship to outbreaks. We postulated that Kimchi ripening can reduce the infectivity of norovirus, in order to test this hypothesis, we carried out a model experiment. Since norovirus is currently regarded as non-culturable, feline calicivirus (FCV) was used as a surrogate to examine the activation of norovirus with Kimchi ripening. In commercial well-prepared Kimchi, the infectivity ($TCID_{50}$) of FCV decreased by 2 log every 12 hours and reached the limit of detection after 48 hours during over-aging at $25^{\circ}C$. During storage at $4^{\circ}C$, the infectivity ($TCID_{50}$) of FCV decreased slowly and reached 5.00 $TCID_{50}$ after 48 hours. The low pH appears to affect the infectivity of FCV directly via organic acids produced by ripening during over-aging and storage. In neutralized lab-prepared Kimchi (pH 7.0), the infectivity ($TCID_{50}$) of FCV also decreased and reached the limit of detection after 72 hours at $4^{\circ}C$. This indicates that there are substances beside organic acids in Kimchi that originate from the raw materials and are produced during ripening. Among the raw materials, salt-fermented anchovies and garlic showed high direct antiviral activity. The main factor decreasing the infectivity of FCV in Kimchi was the high acidity caused by organic acids, regardless of the type, produced by ripening. Furthermore, unknown secondary products of microorganisms associated with Kimchi ripening and antiviral materials originating from raw material might contribute to the decreased infectivity of FCV, the surrogate of norovirus.