• Analytical Science and Technology
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• v.23 no.5
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• pp.437-445
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• 2010

The aim of this study was to develop an analytical method for sulfonamide antibiotics (sulfadiazine, sulfamerazine, sulfamethazine, sulfamethoxazole, sulfathiazole) and their metabolites ($N^4$-acetylsulfadiazine, $N^4$-acetylsulfamerazine, $N^4$-acetylsulfamethazine, $N^4$-acetylsulfamethoxazole, sulfamethoxazole-$N^1$-glucuronide) in environmental samples. The solid phase extraction (SPE) with LC/ESI-MS/MS have been used for the analysis of target compounds, and the recoveries of SPE clean-up were at the range of 12-94% for C18 cartridge, 60-95% for HLB cartridge, 25-123% for MCX cartridge, and 70-90% for tandem HLB/MCX. By established method, detection limit, recovery, and relative standard deviation were 0.001~0.187 ng/mL, 66~115%, and 5~17%, respectively. This method was effective and sensitive to use for the simultaneous determination of sulfonamide antibiotics and their metabolites in environmental samples. Four sulfonamide antibiotics were detected at the range of 0.008~2.153 ng/mL. For metabolites, only $N^4$-acetylsulfamethoxazole was detected, but the concentration was under the MDL level.

• Journal of the Korea Organic Resources Recycling Association
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• v.20 no.4
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• pp.97-105
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• 2012

This study examined for possibility of the food wastewater incineration treatment method as one of overland treatment method by incineration through liquefied spray of food wastewater when incinerating domestic wastes under operation and for the relationship, etc of air discharge material discharged in incineration, and the results of study are as follow: The food wastewater as one of overland treatment method was analysed 94-96% of moisture contents. Temperature of incinerator outduct during mixed incineration of food wastewater with MSW was average $897^{\circ}C$ and incineration of only MSW was $925^{\circ}C$. Temperature of the mixed incineration of food wastewater was dropped about $28^{\circ}C$ by incineration of only MSW. Concentration of nitrogen oxides(NOx) among air discharge gases was studied by 50ppm, 46ppm when inputting $200{\ell}/hr$, $300{\ell}/hr$ into the incinerator as the quantity of food wastewater. In the mixed incineration of food wastewater, generation speed of scales in the inside of a tubular exhaust gas boiler became rapid and the scale generation quantity became large but the exhaust gas boiler normally operated since scales were removed in cleaning of the tube with a compressive air cleaning facility and there was no opening clogging phenomena in a filter cloth of the filtering dust collector. The overland treatment method, not ocean dumping of food wastewater can be proposed as a technology since mixed incineration of food wastewater with MSW in the existing domestic waste incineration plant is possible, and operation costs of the incineration facility were reduced since use of chemicals such as ammonia and urinary hydrogen ion excretion, etc used in incineration facilities for removing nitrogen oxides(NOx).

• Journal of Plant Biotechnology
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• v.30 no.1
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• pp.47-52
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• 2003

Anthers from several lines of carrot (Daucus carota L.) were plated on the semi-solid B$_{5}$, basal medium supplemented with 2,4-D and NAA at two concentrations, 1.0 and 2.0 mg/L plus 0.2 mg/L BAP (benzylaminop-urine). Anthers of the most lines on the B$_{5}$ basal medium with 2,4-D showed higher percentages of callus formation than those with NAA. Particularly, in line 45477, highest percentages of callus formation (50%) were observed on B$_{5}$ medium with 1.0 mg/L 2,4-D plus 0.2 mg/L BAP. With 1.0 mg/L 2,4-D, two months was sufficient for initiation of callus development. Calli were regenerated into plantlets through embryogenesis onto regeneration medium without any growth regulators. When callus showing yellowish and soft structure was cultured, it yielded green plants at high regeneration rates, The response of anthers in callus induction and plant regeneration was different among lines investigated. Optimal callus induction and plant regeneration could be obtained through manipulating the concentration of growth regulators. Plantlets after transfer to perlite were grown successfully in greenhouse conditions. Anther culture of carrot will be used as a useful breeding tool in future.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.34 no.8
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• pp.755-760
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• 2010

In this study, we mainly focused on the PM (Particulate Matter) emission characteristics of a diesel engine. To analyze particle behavior in the tail-pipe, particle emission was measured on the engine-out (downstream of turbocharger), each upstream and downstream both of DOC (Diesel Oxidation Catalyst) and DPF (Diesel Particulate Filter). Moreover, particle emission contours on each sampling point were constructed. The reduction efficiency of particle number concentration and mass through the DOC and DPF was studied. Parameters such as EGR (Exhaust Gas Recirculation) and the main injection timing were varied in part load conditions and evaluated using the engine-out emissions. The DMS500 (Differential Mobility Spectrometer) was used as a particle measurement instrument that can measure particle concentrations from 5 nm to 1000 nm. Nano-particles of sizes less than 30 nm were reduced by oxidation or coagulated with solid particles in the tail-pipe and DOC. The DPF has a very high filtration efficiency over all operating conditions except during natural regeneration of DPF.

• Korean Journal of Food Science and Technology
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• v.40 no.6
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• pp.633-642
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• 2008

Several domestic new varieties of grapes were utilized for the fermentation of wines, including Cabernet Sauvignon, NY 21576, Canner, SV 18315, Agawan, and Black Bagal red wines, and Naples, Aligote, and Alicante white wines. The oBx values of the grapes ranged between 17 and $20^{\circ}Bx$. Soluble solid content was adjusted to $21^{\circ}Bx$ by adding sugar for all grapes and fermented at $20^{\circ}C$ for 2 weeks. Black Bagal and Cabernet Sauvignon were relatively slower than other grapes with regard to alcohol production rate. The L value of wine made from Agawan and NY 21576 were lower and darker than those of wines prepared from other grapes. Wine made from NY 21576 grapes had a polyphenol concentration of 1.40 mg/mL, which was higher than that of any other wine, whereas wines made from MBA and all white wines evidenced value of only 0.55 mg/mL and 0.15 mg/mL, respectively, after 2 weeks of fermentation. The sensory evaluations demonstrated that the quality of red wines made from NY 21576, Cabernet Sauvignon, Black Bagal, and that of white wines made from Naples grapes were favorable among the different grape variants.

• Korean Journal of Food Science and Technology
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• v.45 no.3
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• pp.267-273
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• 2013

We aimed to improve the flavor quality of plain yogurt, which is known to be sour and less desirable in flavor, varying concentrations of a buckwheat saccharification solution (BSS) were added to milk, followed by fermentation with commercially available mixed strains of lactic acid bacteria. Volatile compounds were analyzed using the gas chromatography-headspace-solid phase microextraction (GC-HS-SPME) method. Fermentation properties, including pH, titratable acidity, viable cells, viscosity, and color value were also measured. Eleven volatile compounds were identified with GC-MS. Of which, diacetyl, butanoic acid, and 2-heptanone proportionally increased as the levels of BSS increased. Undesirable compounds such as acetic acid and 2-butanone, decreased as BSS concentration increased. Fermentation properties were significantly altered with the addition of BSS. Our findings indicate that the flavor quality of plain yogurt can be improved by adding BSS for fermentation, with an additional health benefit from buckwheat.

• Horticultural Science & Technology
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• v.32 no.6
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• pp.762-770
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• 2014

This study was conducted to elucidate the influence of prohexadione-calcium (Pro-Ca) application on shoot growth and fruit quality in 'Fuji'/M.9 mature apple trees. Pro-Ca was applied at concentrations ranging from 100 to $400mg{\cdot}L^{-1}$ one time at petal fall (PF; 5-10 cm terminal shoot growth) to the whole canopy of the tree, or at 100, 125, $150mg{\cdot}L^{-1}$ concentrations two times, at PF and then 4-8 weeks after PF. Pro-Ca treatment generally reduced mean shoot growth, with its effect being proportional to the application rate. Pro-Ca at $400mg{\cdot}L^{-1}$ significantly reduced the shoot growth by 15-22% compared to the control, while its effect was not significantly different from Pro-Ca $200mg{\cdot}L^{-1}$. Pro-Ca treatments induced higher occurrence of secondary growth compared to the control. Pro-Ca treatment increased the photosynthetic rate by 5-10% relative to the control, and also increased soluble solid concentration and fruit red color. However, fruit weight was significantly reduced by $400mg{\cdot}L^{-1}$ Pro-Ca, which was attributable to the greater secondary growth caused Pro-Ca $400mg{\cdot}L^{-1}$ treatment compared to the control and Pro-Ca $200mg{\cdot}L^{-1}$ treatment.

• Journal of the Korean Society of Food Culture
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• v.28 no.1
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• pp.78-88
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• 2013

Marinated beef galbi is a traditional Korean dish cooked with soy sauce, pear juice, onion, sesame oil, and sugar. However, there are many differences in beef galbi, including flavor and physicochemical aspects, depending on cooking conditions. Therefore, the physicochemical characteristics of marinated beef galbi prepared through various recipes was evaluated for its effects on pH, texture, aging, proteolysis, heating conditions, cooking time, and flavor compounds (pyrazines, IMPs, or FAAs). There were significant differences in salt concentration (0.8~3.03%), pH (4.89~6.22), and solid soluble contents (1.34-6.31 Brix) between recipes in this study. In the Pearson assay for sensory evaluation, overall preference correlated well with texture (a well-known sensory attribute in meat evaluation). Controlling the pH of meat through soaking in lemon solution, alkali water, phosphate, and baking powder solution, improved water holding capacity as much as 9 to 15% compared with the control. The myofibril index (MFI) of marinated meat stored at $4^{\circ}C$ increased 32% with 24 hours of aging and reached 39% at 48 hours of aging, and its fragmentation was observed through microscopy. SDS-PAGE showed hydrolysis of acid-soluble collagen by the pear juice, possibly related to meat tenderness. On the basis of surface temperature, the cooking time was estimated to be 8 minutes with pan heating at $170^{\circ}C$, 6 minutes at $270{\sim}300^{\circ}C$, and 4 minutes with charcoal at $700{\sim}900^{\circ}C$. Different pyrazine compounds, such as 2-methyl-3-phenylpyrrol(2,3-b) pyrazine (the typical product of the browning reaction) was mainly detected, and IMP (one of the main taste compounds in beef) was in higher amounts with the charcoal treatment, potentially related to its flavor preference among treatments. Our results demonstrate an effective case study and cooking system for beef galbi.

• Applied Biological Chemistry
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• v.49 no.4
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• pp.343-348
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• 2006

To investigate the immunostimulating and anticancer activities from hot water extract of Capsosiphon fulvescens, tumor cell toxicity, sarcoma-180 growth inhibition activity, complement system-activity, intestinal immune system and oral toxicity were performed. The extract of Capsosiphon fulvescens was prepared by hot water and precipitated by using ethanol. Partially purified extract (CFE) was obtained after dialysis and ultrafiltration. The polysaccharide compositions consisted of xylose(19.1%), fucose(15.3%), mannose(4.2%) and galactose(7.9%). The tumor cell toxicity of CFE slightly showed at high concentrations of 10-30 ${\mu}g/ml$, but inhibition ratio against mouse solid tumor was more increased for CFE of 40.1-59.4% than the control. Blood leukocyte counts increased to a maximum of 83% including liver, spleen and thymic of mouse. Immunoglobulin A binding amounts showed a high level of CFE of $2,454{\pm}113.8-2,670{\pm}133.1{\mu}g/mg$ in comparison with the control of $2,092{\pm}123.0{\mu}g/mg$. Acute toxicity of CFE was not detected at the concentration of 2,000 mg/kg in normal mouse.

• Korean Journal of Environmental Agriculture
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• v.39 no.3
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• pp.246-252
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• 2020

BACKGROUND: Pesticides are broadly used to control weeds and pests, and the residues remaining in crops are managed in accordance with the MRLs (maximum residue limits). Therefore, an analytical method is required to quantify the residues, and we conducted a series of analyses to select and validate the quick and simple analytical method for tolpyralate in five agricultural products using QuEChERS (quick, easy, cheap, effective, rugged and safe) method and LC-MS/MS (liquid chromatography-tandem mass spectrometry). METHODS AND RESULTS: The agricultural samples were extracted with acetonitrile followed by addition of anhydrous magnesium sulfate, sodium chloride, disodium hydrogencitrate sesquihydrate and trisodium citrate dihydrate. After shaking and centrifugation, purification was performed with d-SPE (dispersive-solid phase extraction) sorbents. To validate the optimized method, its selectivity, linearity, LOD (limit of detection), LOQ (limit of quantitation), accuracy, repeatability, and reproducibility from the inter-laboratory analyses were considered. LOQ of the analytical method was 0.01 mg/kg at five agricultural products and the linearity of matrix-matched calibration were good at seven concentration levels, from 0.0025 to 0.25 mg/L (R²≥0.9980). Mean recoveries at three spiking levels (n=5) were in the range of 85.2~112.4% with associated relative standard deviation values less than 6.2%, and the coefficient of variation between the two laboratories was also below 13%. All optimized results were validated according to the criteria ranges requested in the Codex Alimentarius Commission (CAC) and Ministry of Food and Drug Safety (MFDS) guidelines. CONCLUSION: In conclusion, we suggest that the selected and validated method could serve as a basic data for detecting tolpyralate residue in imported and domestic agricultural products.