• Journal of Life Science
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• v.28 no.10
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• pp.1163-1169
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• 2018

In order to utilize the residue that is thrown away after an onion harvest, we analyzed the physiological activity and cytotoxicity of fermented and hot water extracts of the residue. The pH of the extracts were all acidic, and organic matter content was 0.75% in the fermented extract and four times more than 0.19% in the hot water extract. The contents of nitrogen, phosphoric acid, calcium, and magnesium components, except for the potassium component among macroelements, were higher in the fermented extract than in the hot water extract. The content of iron and silicon among the micro-elements was also higher in the fermented extract than in the hot water extract. In addition, the content of boron was higher in the hot water extract than in the fermented extract. The total polyphenol contents of the fermented and hot water extracts were $16.2{\pm}3.3mg{\cdot}g^{-1}$ and $14.6{\pm}1.4mg{\cdot}g^{-1}$, respectively, which was $1.6mg{\cdot}g^{-1}$ higher in the fermented extract than in the hot water extract. However, the total flavonoid contents of the fermented and hot water extracts were $0.1{\pm}0.1mg{\cdot}g^{-1}$ and $4.8{\pm}0.7mg{\cdot}g^{-1}$, respectively, which was $4.7mg{\cdot}g^{-1}$ higher in the hot water extract than in the fermented extract. DPPH and ABTS radical scavenging ability for antioxidant activity were higher in the hot water extract than the fermented extract. The cytotoxicity of the extract using MTT assay showed cell viability of 101.6% and 97.9% in the fermented and hot water extracts, respectively. It was confirmed that there was no cytotoxicity in either extract.

• Journal of Wetlands Research
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• v.16 no.3
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• pp.431-440
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• 2014

To propose the improvement and management plans to strengthen the pollutant removal efficiency of dam reservoir's constructed wetlands(CWs), the operation status and configuration of CWs (including water depth, operational flow, water flow distribution, residence time, and pollutant removal efficiency, aspect ratio, open water/vegetation ratio etc.) were analyzed in 10 major wetlands constructed in dam reservoirs. The pollutant concentrations in the inflows of the studied CWs were lower than those of American and European constructed wetlands. Especially, organic matter concentrations in all of inflows were below 3 mg/L(as BOD) due to advanced treatment of sewage disposal plant and an intake of low concentration water during dry and normal seasons. The average removal efficiency of total nitrogen(TN) and total phosphorus(TP) for 10 CWs ranged from 7.6~67.6%(mean 24.9%) and -4.9~74.5%(mean 23.7%), respectively, showing high in wetlands treating municipal wastewater. On the other hand, the removal efficiency of BOD was generally low or negative with ranging from -133.3 to 41.7%. From the analysis of the operation status and configuration of CWs, it is suggested that the low removal efficiency of dam reservoir's CWs were caused by both structural (inappropriate aspect ratio, excessive open water area) and operational (neglecting water-level management, lack of facilities and operation for first flush treatment, lake of monitoring during rainy events) problems. Therefore, to enable to play a role as a reduction facility of non-point source(NPS) pollutants, an appropriate design and operation manuals for dam reservoir's CW is urgently needed. In addition, the monitoring during rainy events, when NPS runoff occur, must be included in operation manual of CW, and then the data obtained from the monitoring is considered in estimation of the pollutant removal efficiency by dam reservoir's CW.

• The Korean Journal of Pesticide Science
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• v.18 no.3
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• pp.123-129
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• 2014

The present work was aimed to determine the pre-harvest residue limits (PHRLs) and the safety management of commonly used pesticides namely buprofezin and penthiopyrad on oriental melon (Cucumis melon var. makuwa). In this study, the buprofezin (diluted two thousand fold) and penthiopyrad (diluted four thousand fold) were sprayed single time on oriental melon in the cultivation areas Sangju (site 1) and Sungju (site 2). Oriental melon were randomly collected from the both areas at the end of 0 (2 hours after pesticides spaying), 1, 2, 3, 5, 7, 9 and 10 days. For analysis, each samples were partitioned twice (80 and 70 mL) with dichloromethane and purified by florisil SPE cartridge. Finally, the residual amounts of both pesticides in all samples were analyzed using gas chromatography/nitrogen phosphorus detector (GC/NPD). In this study, the method limit of quantification (MLOQ) for both buprofezin and penthiopyrad in oriental melon was found to be $0.01mg\;kg^{-1}$ and their recovery levels were 91.1~98.6% and 90.0~104.6%, respectively. Further, the calculated biological half-life for buprofezin and penthiopyrad in oriental melon were 3.9 and 3.5, and 3.0 and 2.7 days in site 1 and 2, respectively. The results of this study found that the PHRLs for buprofezin and penthiopyrad were 4.24 and $2.31mg\;kg^{-1}$, respectively at 10 days before harvest. Consequently, the present study suggest that the residual amounts of both pesticides will be lower than the maximum residue limits (MRLs) when oriental melon is harvested.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.34 no.6
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• pp.611-616
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• 2001

The bacteriological and physiochemical analysis of seawater in Tongyeong harbor was conducted to evaluate sanitary conditions, The samples were collected at 6 stations established once a month from January to December, 2000. During the study period, the ranges of temperature, transparency, chemical oxygen demand, dissolved oxygen, dissolved nitrogen, phosphate and chlorophyll-a were $6.8\sim25.2^{\circ}C,\;1.0\sim2.5\;m,\;1.79\sim2.41\;mg/L,\;5.7\sim10.1\;mg/L,\;6.59\sim10.53{\mu}g-at/L,\;0.56\sim1.01{\mu}g-at/L\;and\;1.21\sim9.54\;mg/m^3$, respectively, The viable cell counts of seawater in Tongyeong harbor ranged from $3.0\times10^4CFU/mL\;to\;6.9\times10^6CFU/mL$. The coliform group and fecal coliform MPN's of the samples were ranged $23\~4,600\;MPN/100\;mL$ (means 540 MPN/100 mL) and $11\~1,600\;MPN/100\;mL$ (means 210 MPN/100 mL), respectively, The coliform group was classified with IMViC reactions and pathogenic vibrios were analyzed. Two hundred eighteen strains that were obtained from seawater samples in Tongyeong harbor represented Escherichia coli group, $66.1\%$; Citrobacter freundii group, $11.0\%$; Enterobacter aerogenes, $9.6\%$; and unknown, $13.3\%$, respectively. During the study period, infectious bacteria such as Vibrio cholerae O1, Salmonella sp. and Shigella sp. were not detected from the samples, but detection ratios of V. parahaemolyticus, V cholerae non-O1 and V. vulnificus were $10.0\sim30.1\%$.

• Journal of the Korean Chemical Society
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• v.54 no.5
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• pp.541-550
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• 2010

A new $N_4O_3$ heptadentate ligand, N,N'-Bis(2-hydroxybenzyl)-1,3-bis[(2-aminoethyl)amino]-2-propanol(H-BAP 4HCl)was synthesized. The hydrochloric acid salts of Br-BAP 4HCl, Cl-BAP 4HCl, $CH_3O$-BAP 4HCl and $CH_3$-BAP 4HCl containing Br-, Cl-, H-, $CH_3O-$ and $CH_{3^-}$ groups at the para-site of the phenol group of the H-BAP were synthesized. The structures of the ligands were confirmed by C. H. N. atomic analysis and $^1H$ NMR, $^{13}C$ NMR, UV-visible and mass spectra. The elemental stepwise protonation constants(${logK_n}^H$) of the synthesized $N_4O_3$ ligands showed six steps of the proton dissociation. The orders of the overall dissociation constants($log{\beta}_p$) of the ligands were Br-BAP < Cl-BAP < H-BAP < $CH_3O$-BAP < $CH_3$-BAP. The orders agreed well with that of Hammett substituent constants($\sigma_p$). The calculated stability constants($logK_{ML}$) between the ligands and transition metal ions agreed well with the order of the overall proton dissociation constants of the ligands but they showed a reverse order in Hammestt substituent constants($\sigma_p$). The order of the stability constants between the transition metal ions with the ligands were Co(II) < Ni(II) < Cu(II) > Zn(II) > Cd(II) > Pb(II).

• Food Science and Preservation
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• v.24 no.8
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• pp.1168-1179
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• 2017

In this study, we tried to screen the Bacillus strain having safety probability by isolation of strains from traditional fermented food, measurement of probiotic properties, and the fermentative characteristics of Cheonggukjang. We isolated 400 Bacillus-like isolates from traditional fermented foods. Selected strains examined on the prevalent characteristic such as extracellular enzyme and antibacterial activities, and their safety probability was confirmed by biogenic amine productivity, hemolytic, and harmful substances and enzyme productivity. We selected the 5 strains by analysis of biogenic amine, antibacterial and B. cereus toxic associated gene. Five selected strains were examined on cell surface hydrophobicity, and bile and acid tolerance, and we selected the SRCM100730 as the final strain. SRCM100730 was confirmed B. amyloliquefaciens by 16S rRNA sequencing, and named the B. amyloloquefaciens SRCM100730 (KCCM11966P). Finally, we manufactured Cheonggukjang using SRCM100730 for confirmation of fermentation properties. Manufactured Cheonggukjang did not contain B. cereus, and showed that ${\gamma}$-PGA and extracellular enzyme activities were superior to commercial Chunggukjang. Amino nitrogen content was 544.02 mg% and 26 free amino acid were detected, and the bitterness-related amino acid content was lower than commercial Cheonggukjang. Especially, the amount of GABA was 3 fold higher than commercial Cheonggukjang. These results suggest that SRCM100730 have high availability in commercial probiotics market and fermented food industry.

• Korean Journal of Plant Resources
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• v.27 no.1
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• pp.60-71
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• 2014

This study was conducted to identify the potential of rape stalk as a raw material for biorefinery process of rape flower. At first, rape stalk (RS) was immersed in distilled water (DW), acetic acid (AA), oxalic acid (OA), sulfuric acid (SA) and sodium hydroxide (SH) solutions, and the content of reducing sugars liberated from immersed RS was analyzed. Glucose, xylose, arabinose and sucrose were detected varying with the immersion type. In particular, 1% AA-immersion of RS for 72 hr was the most effective conditions to liberate glucose from RS. Secondly, the RS residues were used for elementary analysis and fabrication of fuel pellets. In addition to the solution type, concentration of immersion solutions (0%, 1%, 2%) and immersion time (24, 72, 120 hr) were used as experimental factors. The contents of nitrogen, sulfur and chlorine reduced effectively through the immersion of RS in DW, AA and OA solutions. For properties of RS-based pellets, bulk density and higher heating value of RS-based pellets greatly increased with the immersion of RS, and the qualities were much higher than those of the A-grade pellet of the EN standards. Ash content decreased remarkably through the immersion of RS, and was satisfied with the A-grade pellet standard. Durability was negatively affected by the immersion of RS, and did not reached to B-grade of the EN standard. In conclusion, acid immersion of RS can be a pretreatment method for the production of fuel pellet and bioethanol, but use of the immersed RS for the production of high-quality pellets might be restricted due to low durability of immersed-RS pellets. Therefore, further studies, such as investigation of detailed immersion conditions, fabrication of mixed pellets with wooden materials and addition of binders, are needed to resolve the problems.

• Journal of Life Science
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• v.17 no.11
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• pp.1562-1570
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• 2007

This experiment was conducted to develop fertilizer which promotes plant growth as well as suppressing pathogenic fungi. The fertilizer was made from the mixture of Ju-Back (Korean rice wine cake) and indigenous rhizosphere-bacterium. The main ingredients of Ju-Back were investigated as 6.04% total nitrogen, 42.59% total carbohydrate, 1.01% available phosphate, 73.42% organic matter, 7.72% potassium oxide, 1.35% calcium oxide, 0.53% magnesium oxide. The enzyme activities of Ju-Back were estimated to be 980 units/g for ${\alpha}-amylase$, 300 units/g for glucoamylase, and 1800 units/g for acid pretense. Indigenous rhizosphere bacteria which produced antifungal agent were isolated from soil, and was selected KMU-13 strain which can antagonize against various plant pathogenic fungi (Botrytis cinerea KACC 40573, Sclerotinia sclerotiorum KACC 41065, Fusairum oxysporum KACC 40052, Pythium aphanidermatum KACC 40156, Phytophthora capsici KACC 40476 and Glomerella cingulata KACC 40299). KMU-13 strain was identified as Bacillus subtilis KMU-13 by biochemical and 16s rDNA analysis. The organic fertilizer was made as prototype which was composed 20% Ju-Back, 70% carrier, 9.7% microorganism cultivated solution, 0.3% trace-element. We also investigated an application of fertilizer using Ju-Back for cultivating lettuce (Lactuca sativar) which were grown in three soil conditions that had chemical fertilizer, barnyard manure, lime power, urea, potassium chloride and superphosphate as a control, the whole quantity (80 kg/10a) of posted fertilizer with the control and the half quantity (40 kg/10a) with the control. The growth characteristics were examined and analysed with several weeks interval from 3 weeks to 8 weeks on head length (cm), head width (cm/head), number of leaf and fresh weight (g/plant). The results are summarized as follows. The head width and fresh weight of lettuce were the highest at posted fertilizer 1 (whole quantity) was applied chemical, organic matter (Ju-Back) and carrier. The head length was the highest at posted fertilizer 2 (whole quantity) was applied Ju-Back only.

• Korean Chemical Engineering Research
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• v.44 no.6
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• pp.659-668
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• 2006

The optimization of supercritical water oxidation (SCWO) process for decomposing nitromethane was studied by means of a design of experiments. The optimum operating region for the SCWO process to minimize COD and T-N of treated water was obtained in a lab scale unit. The authors had compared the results from a SCWO pilot plant with those from a lab scale system to explore the problems of scale-up of SCWO process. The COD and T-N in treated waters were selected as key process output variables (KPOV) for optimization, and the reaction temperature (Temp) and the mole ratio of nitromethane to ammonium hydroxide (NAR) were selected as key process input variables (KPIV) through the preliminary tests. The central composite design as a statistical design of experiments was applied to the optimization, and the experimental results were analyzed by means of the response surface method. From the main effects analysis, it was declared that COD of treated water steeply decreased with increasing Temp but slightly decreased with an increase in NAR, and T-N decreased with increasing both Temp and NAR. At lower Temp as $420{\sim}430^{\circ}C$, the T-N steeply decreased with an increase in NAR, however its variation was negligible at higher Temp above $450^{\circ}C$. The regression equations for COD and T-N were obtained as quadratic models with coded Temp and NAR, and they were confirmed with coefficient of determination ($r^2$) and normality of standardized residuals. The optimum operating region was defined as Temp $450-460^{\circ}C$ and NAR 1.03-1.08 by the intersection area of COD < 2 mg/L and T-N < 40 mg/L with regression equations and considering corrosion prevention. To confirm the optimization results and investigate the scale-up problems of SCWO process, the nitromethane was decomposed in a pilot plant. The experimental results from a SCWO pilot plant were compared with regression equations of COD and T-N, respectively. The results of COD and T-N from a pilot plant could be predicted well with regression equations which were derived in a lab scale SCWO system, although the errors of pilot plant data were larger than lab ones. The predictabilities were confirmed by the parity plots and the normality analyses of standardized residuals.

• Restorative Dentistry and Endodontics
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• v.33 no.4
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• pp.332-340
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• 2008

The purpose of this study was to evaluate the viability of periodontal ligament cell in rat teeth using slow cryopreservation method with magnetic field through MTT assay and TUNEL test. For each group, 12 teeth of 4 weeks old white female Sprague-Dawley rat were used for MTT assay, and 6 teeth in TUNEL test. The Maxillary left and right, first and second molars were extracted as atraumatically as possible under tiletamine anesthesia. The experimental groups were group1 (immediately extraction), group 2 (cold preservation at 4$^{\circ}C$ for 1 week), group 3 (rapid cryopreservation in liquid nitrogen), group 4 (slow cryopreservation with magnetic field of 1 G), and group 5 (slow cryopreservation). F medium was used as preservation medium and 10% DMSO as cryoprotectant. After preservation and thawing, the MTT assay and TUNEL test were processed. One way ANOVA and Scheffe method were performed at the 95% level of confidence. The value of optical density obtained after MTT analysis was divided by the value of eosin staining for tissue volume standardization. In both MTT assay and TUNEL test, it had showed no significant difference among group 3, 4, and 5. And group 3 had showed higher viability of periodontal ligament cell than group 2. From this study, slow cryopreservation method with magnetic field can be used as one of cryopreservation methods.