• Journal of Life Science
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• v.24 no.10
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• pp.1078-1084
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• 2014

Here, we showed that Acanthocoris sordidus extract inhibited both cell and DNA damage caused by oxidative stress. In a radical scavenging assay, the scavenging activity of the A. sordidus extract against 1,1-diphenyl-2-picrylhydrazyl (DPPH) and hydroxyl radicals was 48.9% and 37.8%, respectively, that of ascorbic acid, which was used as a positive control. The ferrous iron chelating activity of the A. sordidus extract was 80.0% compared to that when ethylenediaminetetraacetic acid (EDTA) was used a control. To verify the inhibitory effect of the extract on oxidative cell damage induced by reactive oxygen species (ROS), a lipid peroxidation assay was performed. The results showed that peroxidation was completely inhibited in an extract-treated group compared to a radical-treated group. The level of p21 protein expression was 68.1% that of a control sample. The DNA cleavage-inhibiting property of the A. sordidus extract-treated group was 53.3% that of a control group. Moreover, the phosphorylation of the H2AX protein was reduced to 39.0% of that treated with radical agents, indicating that the extract might inhibit the DNA damage that causes radical oxidation. Taken together, our findings suggest that the A. sordidus extract is effective not only in repressing oxidation by free oxygen radicals and hydroxyl radicals but also in decreasing cell and DNA damage caused by oxidative stress.

• Journal of the Korean earth science society
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• v.37 no.1
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• pp.40-51
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• 2016

The problem has been pointed out that the domestic design response spectrum does not reflect site amplification, particularly in the high frequency bands, including the fact that site specific response spectrum from the observed ground motions appears relatively higher than design response spectrum. Among various methods, this study applied H/V spectral ratio of ground motion for estimating site amplification. This method, originated from S waves and Rayleigh waves, recently has been extended to Coda waves and background noise for estimating site amplification. For limited time of periods, 4 electric substation sites had operated seismic stations at two separate locations (bedrock and borehole) within each substation site. H/V spectral ratio of S wave, Coda wave, and background noise, was applied to 36 accelerations of 3 macro earthquakes (Odaesan, Jeju and Gongju earthquakes), larger than magnitude 3.4. observed simultaneously at each bedrock location within 4 electric substation sites. Site amplifications at the bedrock location of 4 sites were compared among S wave, Coda wave energy, and background noise, and then compared to the previous results from the borehole location data. The site classification was also tried using resonancy frequency information at each site and location. The results suggested that all the electric substation sites showed similar site amplification patterns among S wave, Coda wave, and background noise. Each station showed its own characteristics of site amplification property in low, high and specific resonance frequency ranges. Comparison of this study to other results using different method can give us much more information about dynamic amplification of domestic sites characteristics and site classification.

• Journal of Life Science
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• v.14 no.2
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• pp.239-244
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• 2004

This study was carried out to clarify the effect of addition of mugwort and carcass grade on the quality and sensory properties of loin hams. The volatile basic nitrogen, 2-thiobarbituric acid reactive substances, total bacterial count, water holding capacity and calorie of loin hams were not significantly different among hams, but the pH and residual nitrite of loin hams with mugwort were significantly lower than that of loin hams without mugwort. The fat content of grade B loin hams were higher than that of grade E loin hams, and the protein and total amino acid content of grade E loin hams were higher than that of grade B loin hams. The free amino acid, saturated fatty acid and unsaturated fatty acid were not significantly different among loin hams. The $L^{＊}$ value of grade B loin hams were higher than that of grade E loin hams, the a value of grade E loin hams were higher than that of grade B loin hams, and the $b^{＊}$ value was not significantly different among loin hams. The hardness, springiness, cohesiveness, gumminess and chewiness were not significantly different among loin hams. The aroma of loin hams without mugwort were superior than that of loin hams with mugwort, and the juiciness of grade B loin hams were superior than that of grade E loin hams. But the color, taste, texture and palatability were not significantly different among loin hams.

• Food Science and Preservation
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• v.24 no.2
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• pp.221-229
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• 2017

The effect of sweet potato on the quality of Doenjang was investigated during fermentation. Viable cells of yeast decreased gradually after 4 weeks of fermentation, but those of aerobic bacteria increased in the late stage. Amylase activity of Doenjang was higher in the late stage of fermentation, while neutral protease maintained high activity during fermentation. Hunter L and b values of Doenjang decreased gradually during fermentation, while a value was increased. The pH of Doenjang decreased gradually until 10 weeks of fermentation, and the titratable acidity was low in the sweet potato added groups. The acid value was low in the Shinyulmi sweet potato added Doenjang. Water activity and oxidation-reduction potential of Doenjang decreased during fermentation. Reducing sugar of Doenjang decreased in the middle stage of fermentation, and it was low in sweet potato added groups. The alcohol content of Doenjang decreased after 2 weeks of fermentation. Amino and ammonia-type nitrogen of Doenjang increased during fermentation and reached the maximum after 10 and 12 weeks of fermentation, respectively. After 12 weeks fermentation, 8% of Shinyulmi sweet potato added Doenjang was more favorable taste, flavor and overall acceptability (p<0.05) than the control or the Yeonwhangmi sweet potato added groups.

• Korean Journal of Medicinal Crop Science
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• v.17 no.6
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• pp.439-444
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• 2009

This study was to set the guidelines of soil chemical components in order to assure the safety and quality of the panax ginseng from physiological disorder. The disorder symptoms appeared on the leaf with yellow spot, atrophy, yellow-brown spot, also showed red skin and rough skin of the root. Occurrence type of physiological disorder in cultivated field divided into two types : type I 'such as, yellow spot' consist of single disorder symptom; type II 'such as, yellow spot and yellow-brown spot' consist of two or more different disorder symptoms. The individual contribution of soil properties to the occurrence type was as follows ; The yellow spot was affected by Na > $NO_3$-N > salinity (EC) in soil. The same results was observed in red skin. Atrophy was affected by $NO_3$-N > salinity (EC) > Ca > Mg. Rough skin was affected by $P_2O_5$>pH>Organic material > K. It showed positive associated to $P_2O_5$, pH and K, but negative associated to organic matter. Simultaneous occurrence of two different disorder, including cases which yellow spot and yellow-brown spot, those were affected by $NO_3$-N > salinity (EC) > Na > Mg. In the case of atrophy plus yellow-brown spot, those also were affected by in the order : $NO_3$-N > salinity (EC) > Ca > Mg > Na. Red-rough skin was affected in the order : salinity (EC) > $NO_3$-N > K > Na. Soil chemical components appear to be related to occurrence of physiological disorder, particularly in salinity (EC) and $NO_3$-N. The salinity (EC) and $NO_3$-N were negative related to plant growth. In addition, exchangeable cation capacity play critical roles in attributing to complex occurrence of physiological disorder.

• Journal of Conservation Science
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• v.34 no.1
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• pp.23-29
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• 2018

This study synthesized poly-urea and used it as a filler material for the restoration of porcelain. The synthesized poly-urea was manufactured as a resin and hardener mix that does not undergo contraction during curing, and is unfading. Given an adhesion strength of $180kg/cm^2$ and shearing strength of $200kg/cm^2$, the synthesized poly-urea exhibited the same efficacy as the epoxy putty currently sold in the market. Moreover, it also overcame the drawback of foaming encountered by urethane restoratives, which are a structurally similar type. The hardening time and pot life could also be controlled using additives. The poly-urea used for the restoration of modern artifacts presented a pot life of approximately one hour and took 12 h for complete hardening ($T_{90}$). When a $2{\times}2{\times}2cm$-sized test sample was added to xylene, poly-urea started to separate approximately two hours later and completed perfect pulverization within the solution 24 h later, demonstrating its reversibility. When directly applied to contemporary artifacts, it demonstrated the potential for restoration, as well as convenience and colorfulness.

• Korean Journal of Environmental Agriculture
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• v.38 no.4
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• pp.273-280
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• 2019

BACKGROUND: The reclaimed lands for agricultural use managed by the Korean government is consisted of 17,145 hectares of lands under construction and 13,384 hectares of completed lands. In order to utilize these reclaimed lands as competitive agricultural complexes, the government is preparing to develop comprehensive development plans for multiple purposes. For rational land-use planning and soil management, information of the soil chemical properties is necessary. METHODS AND RESULTS: From 2013 to 2016, soil samples were collected from 85 representative sampling sites of the reclaimed lands and analyzed for soil chemical properties including electric conductivity (EC), pH, soil organic matter (SOM), and nutrients. The annual mean soil EC ranged from 5.1 to 8.3 dS m^-1 and have continued to decrease over the years (estimation equation with EC as dependent and year as independent variable was y =0.0736x² - 1.4985x + 9.8305, R² = 0.9753). The pH ranged from 7.3 to 7.6, which was higher than the optimum range (5.5~7.0) for agricultural soils. Soil organic matter (8 to 11 g kg^-1) was lower level than the optimum range (20~30 kg^-1). Available silicate (Av.SiO₂) ranged from 169 to 229 mg kg^-1, which was close to the minimum content (≥157 mg kg^-1) for rice paddy field. Available phosphate (Av.P₂O₅) content (24~39 mg kg^-1) was lower than the optimum range (80~120 mg kg^-1) for rice paddy field. CONCLUSION: For efficient agricultural use of reclaimed lands under government management, our results suggest that the application of organic matter and supplying deficient nutrients as well as desalinization is required.

• Korean Journal of Food Science and Technology
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• v.46 no.1
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• pp.51-55
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• 2014

We investigated the feasibility of incorporating Codonopsis lanceolata (C. lanceolata) powder into cookies as a value-added food ingredient. The density and moisture content of the dough was not significantly affected by the addition of C. lanceolata powder (p>0.05); the pH ranged from 6.01-6.51. The spread ratio decreased significantly with the increasing levels of C. lanceolata powder added (p<0.05). The lightness decreased, but both browning and hardness increased significantly with the higher amounts of C. lanceolata powder in the formulation (p<0.05). The 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging activities were increased significantly (p<0.05) and correlated well with increasing amounts of C. lanceolata. In consumer acceptance tests, the addition of C. lanceolata powder, up to 10% (w/w), had a favorable effect on consumer preferences for all the attributes tested. Based on these observations, we recommend cookies with 5% C. lanceolata powder to take advantage of its functional properties without sacrificing consumer acceptability.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.2
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• pp.242-247
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• 2011

Soil management for environment-friendly agriculture depends on the effects of soil microbial activities and soil fertility. To improve soil health for the upland crops, this study evaluated a relationship between soil chemical properties and soil microbial diversities at 25 sites in upland soils in Gyeongnam Province. The average nutrients in the upland soils were 1.7 times for available phosphorous, 1.4 times for exchangeable potassium and 1.5 times for exchangeable calcium higher compared to recommend concentrations in the upland soils. We found a significant positive correlation between the soil organic matter and the soil microbial biomass C (p<0.01). Contents of organic matter and dehydrogenase in the inclined piedmont soils were significantly higher than those in the other topographical soils (p<0.05). In addition, concentrations of organic matter and microbial biomass C in the loam soils were significantly higher than in the silt loam soils (p<0.05). In principal component analyses of chemical properties and microbial populations in the upland soils, our findings suggested that available phosphorous should be considered as potential factor responsible for the clear upland soils differentiation. The soil organic matter was positive correlation with Bacillus sp. and fungi, whereas soil pH was also positive correlation with Pseudomonas sp. in upland soils.

• Journal of the Korean Ceramic Society
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• v.44 no.1 s.296
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• pp.52-57
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• 2007

We synthesized $(La_{1-x}Sr_x)MnO_3$ as a cathode for SOFC by glycine nitrate process (GNP) and knew the different properties of $(La_{1-x}Sr_x)MnO_3$ by using nitrate solution and oxide solution as a starting material. In case of using nitrate solution as a starting material, main crystal phase peak of $LaMnO_3$ increased as Sr content added up and a peak of $Sr_2MnO_4\;and\;La_2O_3$ was showed as a secondary phase. We added Mn excess to control a crystal phase. In this case, the electrical conductivity had a high value 210.3 S/cm at $700^{\circ}C$. On the other side, when we used oxide solution as a starting material, we found main crystal phase of $LaMnO_3$ to increase as Sr content added up and a peak of $La_2O_3$ as a secondary phase. Similary, we added Mn excess to control a crystal phase in this case. We knew $(La,Sr)MnO_3$ powder to sinter well and the electrical conductivity of the sintered body at $1200^{\circ}C$ for 4 h was 152.7 S/cm at $700^{\circ}C$. The sintered $(La,Sr)MnO_3$ powder at $1000^{\circ}C$ for 4 h got the deoxidization peak, depending on the temperature and in case of using nitrate solution as a starting material, the deoxidization peak was showed at $450^{\circ}C$ which is lower than used a oxide solution as a starting material. As a result, when $(La,Sr)MnO_3$ powder was synthesized to add Mn excess and to use nitrate solution as a starting material, we found it to have the higher deoxidization property and considered it as a cathode for SOFC properly. And we found it to have different electrical conductivity the synthesized $(La,Sr)MnO_3$ powder by using different starting materials like nitrate solution and oxide solution which influence a sintering density and crystal phase.