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Simultaneous Determination of Pesticides in Water Using a GC/MS Coupled with Micro Extraction by Packed Sorbent (MEPS-GC/MS를 이용한 농약류 동시 수질분석)

  • Lee, Ki-chang;Lee, Wontae
    • Journal of Korean Society of Environmental Engineers
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    • v.37 no.5
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    • pp.262-268
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    • 2015
  • This study established an analytical method to simultaneously determine six organophosphorous pesticides [methyldemetone-S, diazinon, fenitrothion, parathion, phentoate, and O-ethyl O-(4-nitrophenyl) phenylphosphonothioate (EPN)] and carbaryl in water using a gas chromatography/mass spectrometry (GC/MS) system coupled with on-line micro extraction by packed sorbent (MEPS) and programmed temperature vaporizer (PTV) injector. Polystyrene divinylbenzene (PDVB) was used as a sorbent of MEPS. The effects of elution solvents, pH, elution volume and draw-eject cycles of samples on sample pretreatment process were investigated. Also, quality assurance and quality control (QA/QC) and the recovery of the pesticides in environmental samples were evaluated. The elution was performed using $30{\mu}L$ of a mixed solvent (acetone : dichloromethane = 80 : 20 (v/v)). Sample pretreatment processes were optimized with seven cycles of draw-eject of sample (1 mL) spiking an internal standard and sulfuric acid. At lower pH, the analytical sensitivity of diazinon decreased, but that of carbaryl increased. The method detection limit and the limit of quantification for this method were 0.02~0.18 and $0.08{\sim}0.59{\mu}g/L$, respectively. The method precision and accuracy were 1.5~11.5% and 83.3~129.8%, respectively, at concentrations of $0.5{\sim}5.0{\mu}g/L$. The recovery rates for all the pesticides except carbaryl in various environmental samples ranged 75.7~129.3%. The recovery rate of carbaryl in effluent sample was over 200% whereas carbaryl in drinking water, groundwater, and river water were in the acceptable range.

Microbial and Quality Changes during Storage of Raw Oyster Treated with High Hydrostatic Pressure (초고압 처리한 생굴의 저장 중 미생물수 및 품질 변화)

  • Park, Whan-Jun;Jwa, Mi-Kyung;Hyun, Sun-Hee;Lim, Sang-Bin;Song, Dae-Jin
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.35 no.10
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    • pp.1449-1455
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    • 2006
  • Raw oysters were treated at $10^{\circ}C$ and $22^{\circ}C/350$ Mpa/15 min, and microbial counts and quality were measured during storage of 14 days at $10^{\circ}C$. Total viable cell count (TVCC) in untreated oyster increased greatly during storage from starting inoculum of $1.6\times10^2\;CFU/mL$, and reached to $5.6\times10^2\;CFU/mL$ after 4 days of storage. TVCC of the pressure-treated was about $10^1\;CFU/mL$ right after high hydrostatic pressure treatment and increased slowly during storage, and about $10^3\;CFU/mL$ even after 7 days of storage. Lactic acid bacteria count (LABC) in the untreated was increased greatly during storage from starting inoculum of $3.3\times10^3\;CFU/mL$ at 3 days of storage and $7.2\times10^4\;CFU/mL$ after 4 days of storage. LABC in the pressure-treated was detected only after 5 days of storage, and about $10^2\;CFU/mL$ after 8 days of storage. The pH of the untreated was 6.19 and decreased gradually during storage, and 5.83 after 4 days of storage. The pH of the pressure-treated showed little change during storage, and 6.07, 6.03 and 5.82 after storage of 4, 8 and 14 days, respectively. Volatile basic nitrogen (VBN) in the untreated was 16.8 mg%, and maintained almost constant until 1 day of storage, and then increased suddenly, and 30.1 mg% after 4 days of storage. VBN of the pressure-treated stayed unchanged during storage, and about 20 and 23 mg% even after 4 and 8 days of storage, respectively. Hunter $L^*,\;a^*\;and\;b^*$ values were increased until 2 days of storage and then showed no change during storage. Demerit score was the lowest in the thawed raw oyster, and then in the increasing order of the pressure-treated (4 day and 8 day storage) and the untreated (4 day storage).

Freshness of Satsuma Mandarin Packed in Anti-fogged MA Film with Acid Treated Zeolite (산 처리된 제올라이트와 결로 방지제를 함유한 MA 필름으로 포장한 감귤의 신선도)

  • Park, Hyung-Woo;Ryu, Na-Hee
    • KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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    • v.19 no.1
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    • pp.35-41
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    • 2013
  • This study investigated the effect of functional MA films (FMA) incorporated with zeolite powder treated with 1 N HCL solution and anti-fogging agent on the freshness extension of Satsuma mandarin. Preference, weight loss, total ascorbic acid, sugar content, titratable acidity and gas composition in package of Satsuma mandarin were evaluated during storage at $15^{\circ}C$. After 120 days of storage, the weight loss of mandarin packed with LLDPE film (control, L) was 1%, FMA film (CA) was 1.6%. Total ascorbic acid content of Satsuma manderin in control was 19.97 mg%, those of CA was 24.25 mg%. The titratable acidity of Satsuma manderin in CA was higher than that of control, while soluble solids content of CA was lower than that of control after 120 days. Ethylene gas content of control was 89.5 ppm and those of CA was 73.6 ppm after 120 days. Quality of Satsuma mandarin packed with CA was better than that of control. It was verified that shelf-life of Satsuma mandarin in control was 100 days and those of CA film was 130 days. Quality of Satsuma mandarin was few different between treated with anti-fogging agent and non-treated, but commodity of film treated with anti-fogging agent was considered better than that of non-treated.

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The Assessment of Blood Glucose Distribution according to the Fasting State and Glycemic Control Indicators for Diabetes Screening (금식 여부에 따른 혈당치 분포와 당뇨병 선별을 위한 혈당조절지표의 평가)

  • Kwon, Pil Seung;Rheem, Insoo
    • Korean Journal of Clinical Laboratory Science
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    • v.48 no.4
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    • pp.312-320
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    • 2016
  • This study analyzed the distribution of the blood glucose level according to the fasting status. Moreover, a relationship was analyzed between fasting blood glucose level and glycemic control indicators. A total of 707 outpatients, who visited Dankook University Hospital, were included and classified into either the fasting group and the non-fasting group. The mean blood glucose level of each group was calculated and analyzed by sex, age, and clinic. In addition, blood glucose, HbA1c, fructosamine, and 1,5-AG were measured in 153 fasting health check-up patients, and the correlation between the blood glucose level and glycemic control indicators was evaluated. Blood glucose averages between the two groups (non-fasting 111.9 vs. fasting 103.6 mg/dL) were different (p<0.05); and the mean difference was lower in women (4.8 mg/dL) than in men (12.2 mg/dL). A significant difference of the median glucose values among the age groups was only observed in the non-fasting group (Kruskal-Wallis test, p<0.01), and not in the fasting group. A 1,5-Anhydroglucitol was estimated to be significantly correlated with the fast blood glucose level in the range of the criteria of impaired fasting glucose (IFG). We presented an assessment of the distribution of blood glucose level in accordance with the fasting status among outpatients, and estimated that 1,5-anhydroglucitol was well correlated with the fasting blood glucose than fructosamine and HbA1c, through the analysis of results of health screening subjects. It is suggested that the use of glycemic indicators that reflect short-term blood glucose control can be used together with the blood glucose measurement in the screening of diabetes mellitus.

Improvement of Shoot Regeneration from Scutella-Derived Callus in Rice

  • Kim, Yong-Wook;Cho, Joon-Hyeong;Lee, Jang-Yong
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.49 no.1
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    • pp.52-60
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    • 2004
  • The optimized in vitro culture system was investigated for improvement of regeneration efficiencies by observing the responses of scutella-derived callus of Korean rice (Oryza sativa L.). Large variations of callus induction (43.9-93.9%) and shoot regeneration (0-88.7%) were observed among the rice cultivars depending on medium. However, shoot regeneration was significantly improved by selected utilization of basal medium, growth regulators, and carbon sources. N6 basal medium was more efficient for embryogenic callus induction than MS or LS basal medium, while MS was superior to N6 for shoot regeneration. The calli of highly regenerative cultivars grew faster and showed higher rates of green tissue formation (GT) and shoot regeneration (SR) and lower rate of callus browning (CB) than those of recalcitrant cultivars. Although a higher level of kinetin stimulated the GT and SR in highly regenerative cultivars, $10\textrm{mgL}^{-1}$ kinetin generally suppressed the GT and SR, while CB was accelerated compared to $2\textrm{mgL}^{-1}$ kinetin. Additional benefits of sorbitol combined with maltose (or sucrose) under $5\textrm{mgL}^{-1}$ kinetin were certainly confirmed on regeneration efficiencies compared to sucrose alone as carbon source and osmotic regulator. This combination showed high rate of GT and SR with multiple shoots while low rate of CB. With MSRK5SM-Pr medium ($5\textrm{mgL}^{-1}$ kinetin, 3% sorbitol, 2% maltose, $500\textrm{mgL}^{-1}$ proline), the regeneration efficiencies of total 17 out of 24 cultivars were practically improved 160% on average compared to MSRK2S ($2\textrm{mgL}^{-1}$ kinetin, 3% sucrose) control medium. Especially, the medium was most effective to the cultivars showing a medium level of regenerability such as Daesanbyeo and Dongjinbyeo and Suwon477, enhancing efficiencies more than 300-600% compared to MSRK2S medium.

Design of the RF Front-end for L1/L2 Dual-Band GPS Receiver (L1/L2 이중-밴드 GPS 수신기용 RF 전단부 설계)

  • Kim, Hyeon-Deok;Oh, Tae-Soo;Jeon, Jae-Wan;Kim, Seong-Kyun;Kim, Byung-Sung
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.21 no.10
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    • pp.1169-1176
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    • 2010
  • The RF front-end for L1/L2 dual-band Global Positioning System(GPS) receiver is presented in this paper. The RF front-end(down-converter) using low IF architecture consists of a wideband low noise amplifier(LNA), a current mode logic(CML) frequency divider and a I/Q down-conversion mixer with a poly-phase filter for image rejection. The current bleeding technique is used in the LNA and mixer to obtain the high gain and solve the head-room problem. The common drain feedback is adopted for low noise amplifier to achieve the wideband input matching without inductors. The fabricated RF front-end using $0.18{\mu}m$ CMOS process shows a gain of 38 dB for L1 and 41 dB for L2 band. The measured IIP3 is -29 dBm in L1 band and -33 dBm in L2 band, The input return loss is less than -10 dB from 50 MHz to 3 GHz. The measured noise figure(NF) is 3.81 dB for L1 band and 3.71 dB for L2 band. The image rejection ratio is 36.5 dB. The chip size of RF front end is $1.2{\times}1.35mm^2$.

Identification and Fermentation Characteristics of Lactic Acid Bacteria Isolated from Hahyangju Nuruk (하향주 누룩으로부터 분리한 젖산균의 동정 및 발효 특성)

  • Park, Chi-Duck;Jung, Hee-Kyoung;Park, Hwan-Hee;Hong, Joo-Heon
    • Food Science and Preservation
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    • v.14 no.2
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    • pp.188-193
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    • 2007
  • The purpose of this study was to isolate lactic acid bacteria, useful in the fermentation industry from Hahyangju Nuruk. Five strains were isolated, and identified as Lactobacillus based on growth inhibition by 10% (v/v) alcohol at pH 4.0. Isolated strains were identified to species, and named Lactobacillus plantarum L-3, L. sakei L-10, and L. curvatus strains L-8, L-11, and L-12. Morphological characteristics, physiological data, carbohydrate fermentation patterns, and 16S rRNA sequence data, were all used to characterize the bacterial isolates. L. plantarum L-3 showed the highest lactic acid productivity of all isolates, but grew only poony in the presence of 10% (v/v) alcohol at pH 4.0. The other strains exhibited lower lactic acid productivity than did L. plantarum L-3 and did not grow in the presence of 10% (v/v) alcohol at pH 4.0. The optimal temperature and pH for lactic acid production were $30^{\circ}C$ and pH 6.0 7.0, respectively. The lactic acid productivity of L. plantarum L-3, L. sakei L-10 and the three L. curvatus strains L-8, L-11, and L-12 were (% v/v of culture supematant) 1.55, 1.0, 1.06, 1.0, and 0.99, respectively, at $30^{\circ}C$ and pH 6.0. While L. plantarum L-3 suffered growth inhibition in the presence of 10% (v/v) alcohol, growth of the other strains was inhibited at 8% (v/v) alcohol.

Effect of Plant Growth Regulators on Plant Regeneration from Leaf and Stem Explant Cultures of Sedum erythrostichum Miq. (꿩의비름(Sedum erythrostichum Miq.)의 잎과 줄기 절편으로부터 식물체의 재분화에 미치는 생장조절제의 영향)

  • 윤의수
    • Korean Journal of Plant Tissue Culture
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    • v.24 no.5
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    • pp.285-289
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    • 1997
  • Leaf and stem explants of Sedum erythrostichum Miq. were cultured on MS medium supplemented with various combinations of growth regulators. After two weeks of culture, 100% of the leaf explants formed calli on medium containing 2.0 mg/L 2, 4-D and 1.0 mg/L BA. Callus proliferated when subcultured on medium containing 2.0 mg/L 2, 4-D and 1.0 mg/L BA. Numerous adventitious buds were regenerated from callus cultured on the medium containing 2.0 mg/L NAA and 1.0 mg/L BA. Root formation from shoot was occurred on the MS basal medium containing 1.0 mg/L IAA.

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Fatty Acid Composition of Salt-Fermented Seafoods in Chonnam Area (전남산 젓갈의 지방산 조성)

  • 박복희;박영희
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.22 no.4
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    • pp.465-469
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    • 1993
  • This study was designed to investigate fatty acid composition of salt-fermented seafoods in Chonnam area. The seven samples were analyzed for fatty acid composition. The contents of lipid was highest in salt-fer-mented anchovies and followed by salt-fermented small mullets, salt-fermented oysters, salt-fermented sea-arrows and salt-fermented small shrimps. The ratio of fatty acid composition depended on the samples but the major fatty acids were $C_{l6:0}$, $C_{20:5}$, $C_{l6:1}$, $C_{22:6}$, and $C_{l8:1}$ among all samples. The composition of n-3 polyunsaturated fatty acids was highest in salt-fermented sea-arrows (39.11%) and followed by salt-fermented small shrimps, salt-fermented oysters, salt-fermented anchovies and salt-fermented small mullets. In n-3 polyunsaturated fatty acids, $C_{20:5}$ was relatively abundant in salt-fermented oysters (17.71%) and salt-fermented sea-arrows (16.38%), and $C_{22:6}$ in salt-fermented sea-arrows (22.22%) and salt-fermented small shrimps (15.13~21.50%). However, $C_{22:6}$ was very little in salt-fermented small mullets.l mullets.

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Anti-inflammatory Effect of Coptidis Rhizoma Extract (황련(黃連) 추출물의 항염효능에 관한 연구)

  • Lee, Jeon-Woo;Han, Hyo-Sang;Lee, Young-Jong
    • The Korea Journal of Herbology
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    • v.29 no.5
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    • pp.83-90
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    • 2014
  • Objectives : This research has been done to investigate the anti-inflammatory effect of Coptidis Rhizoma extracts. Method : Coptidis Rhizoma was extracted by $100^{\circ}C$ water. The extract (CC : Extract of Coptis chinensis rhizome) was used to examine its effects on the cell viability of mouse macrophage Raw 264.7 cell line. Also the production of nitric oxide (NO), the c-jun N-terminalkinase (JNK) activation and the production of cytokines such as (IL)-5 were evaluated in lipopolysaccharide (LPS)-stimulated Raw 264.7 cells. After the CC and LPS were applied to Raw 264.7 cells which were cultured for 24 hours, the MTT assay was performed. Result : The CC extracts didn't affect the viability of macrophage cells. However, the extracts inhibited the NO production and the JNK activation significantly in LPS-stimulated macrophage cells treated with 100 and $200{\mu}g/mL$ concentrations. The CC extract, also, impeded the production of inflammation-related factors and cytokines such as KC, VEGF, MCP-1, GM-CSF, IL-$1{\alpha}$, IL-5, IL-6, and IL-12p40 in LPS-stimulated macrophage cells at the concentration higher than $25{\mu}g/mL$. The production of basic-FGF concentration of 50 and $100{\mu}g/mL$, the production of IP-10 at $100{\mu}g/mL$, and the production of IFN-${\gamma}$ at $25{\mu}g/mL$, respectively. Conclusion : The CC prepared using $100^{\circ}C$ water showed the significant anti-inflammatory effect such as the inhibition not only on the production of NO, KC, VEGF, MCP-1, GM-CSF, IL-$1{\alpha}$, IL-5, IL-6, and IL-12p40 in LPS-stimulated macrophage cells at or higher than the concentration of $25{\mu}g/mL$, but also on the JNK activation at 100 and $200{\mu}g/mL$.