• Title/Summary/Keyword: GLC

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Residual Patterns of Strobilurin Fungicides in Korean Melon under Plastic Film House Condition (Strobilurin계 살균제의 시설재배 참외 중 잔류 양상)

  • Park, Eun-Jeong;Lee, Ju-Hee;Kim, Tae-Hwa;Kim, Jang-Eok
    • Korean Journal of Environmental Agriculture
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    • v.28 no.3
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    • pp.281-288
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    • 2009
  • The strobilurin fungicides, azoxystrobin and kresoxim-methyl, were investigated to know the biological half-lives and dissipation patterns in Korean melon under plastic film house condition. Used pesticides for field application were 20% azoxystrobin of suspension concentrate and 47% kresoxim-methyl of water dispersible granule. Two pesticides were sprayed at recommended and double dose rate. Pesticide residues in Korean melon were analyzed until 14 days after application. The azoxystrobin was analyzed by HPLC equipped with UV detector after cleanup with florisil glass column. Initial residue concentrations of azoxystrobin in Korean melon at recommended and double dose rate were 0.09 mg/kg and 0.14 mg/kg, respectively. Those were less than 0.2 mg/kg maximum residue limit of Korean melon established by KFDA. The biological half-lives of azoxystrobin in Korean melon were 4.7 days at recommended dose rate and 7.8 days at double dose rate. Initial concentrations of kresoxim-methyl which was analyzed by GLC-ECD in Korean melon at recommended and double dose rate were 0.10 mg/kg and 0.23 mg/kg, respectively. Those were less than 1.0 mg/kg, MRL. The biological half-lives of kresoxim-methyl in Korean melon were 4.1 days at recommended dose rate and 4.8 days at double dose rate. The residue amounts of both pesticide was lower than MRL and biological half-lives were not so long. Because the weight of Korean melon under plastic film house condition was fast increased during cultivation.

Criteria and Index of Social and Economic Evaluation in River Restoration (하천복원사업의 사회.경제성 평가 기준 및 지표에 관한 연구)

  • Kim, Chong-Won;Yi, Jung-Hun
    • Proceedings of the Korea Water Resources Association Conference
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    • 2007.05a
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    • pp.470-474
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    • 2007
  • 본 논문에서는 하천복원사업으로부터 발생하는 사회 경제적 편익의 측정 및 평가를 위한 기준 및 지표를 다루고자 한다. 하천복원사업의 목적 및 하천의 기능 및 사업의 영향을 기초로 선정된 평가 기준은 크게 생태적 측면과 사회 경제적 측면으로 나눌 수 있다. 본 연구에서 생태적 측면이 강조되는 것은 하천 생태의 다양한 측면을 파악하는 것이 사회 경제성 연구에 있어 풍부한 논의의 가능성을 제공해주는 측면이 있기 때문이다. 이는 하천복원사업이 가지는 복합적인 성격으로 인해 사업의 사회적, 경제적, 생태적 영향이 서로 고립되지 않고 영향을 주고받는 것에서 연유한다. 첫 번째 평가 기준인 생태적 측면에서는 세부기준으로 생태계 및 수문부문 등의 변화를 포함하며, 복원사업 전후의 서식처 및 생물 종 다양성의 변화, 하상의 다양화 등을 지표로 고려할 수 있다. 나머지 큰 평가 기준인 사회 경제적 측면에서는 홍수방지 효과나 수질개선 효과와 같은 우리가 생태계로부터 제공받는 직접적인 서비스나 토지 이용의 변화 및 그 변화에서 야기되는 영향(하천의 친수 기능이나 학습효과 등), 복원사업의 관리 및 비용 측면 등을 세부기준으로 고려할 수 있다. 하천복원사업의 구체적인 평가를 위해, 각 세부기준에 대한 지표는 현 복원사업에서 실시되는 평가기법, 하천복원관련 문헌조사 및 사례조사를 통해 검토하여 일차적으로 선정한다. 각 지표는 고려하고자 하는 특성에 따라 정량화가 용이한 지표와 정성적 측면이 강한 지표로 나뉜다. 이렇게 선정된 지표는 전문가 조사를 통해 지표에 대한 의견을 수렴하여 확정한다.한 치즈곤죽에서는 쓴맛 펩타이드가 형성되었다가 사라짐을 관찰할수 있었다. 한편 지질분해효소를 침가할 경우 총 휘발성산이 4일 이후에 급격히 증가함을 통해 사용한 효소는 유지방을 잘 분해함을 알 수 있었으며 GLC에 의한 유리 지방산의 분석 결과는 Cheddar치즈곤죽은 시판Cheddar 치즈와 비슷하고 Italian형 치즈곤죽은 시판 Italian치즈보다 약간 떨어졌다. Cheddar치즈의 중요한 품미성분인 활성 SH기는 glutathione을 첨가한 치즈곤죽에서 발효 4일부터 증가하였으며 단백질분해효소를 함께 첨가할 경우 그 증가현상이 현저하였다. 단백질분해요소의 첨가유무에 따라 점도 변화는 다른 두 가지 양상으로 나타나 효소를 첨가할 경우 단백질이 분해됨에 따라 점도가 급격히 감소하였다.>${\pm}0.36$) %, 0.34(${\pm}0.27$) %, 0.34(${\pm}0.18$) % 의 오차를 보였다 중간에 6 cm 의 PP 을 위치한 경우에는 에너지별로 1.15(${\pm}1.86$) %, 0.90(${\pm}1.43$)%, 0.86(${\pm}1.01$)% 의 오차를 나타내었다. 이 경우에는 PCD 10 cm 의 경우에 비교적 큰 오차를 보였으며 PCD 10 cm 인 경우를 제외하면 에너지별로 0.47(${\pm}1.17$) %, 0.42(${\pm}0.96$) %, 0.55(${\pm}0.77$0.

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Adsorption of Heavy Metal onto the Extracellular Polysaccharide Produced by the Purple Nonsulfur Photosynthetic Bacteria Rhodopseudomonas sp. KH4 (홍색 비황 광합성 세균 Rhodopseudomonas sp. KH4의 Extracellular polysaccharide의 중금속 흡착)

  • Jeong, Jeong-Hwa;Seo, Pil-Soo;Kong, Sung-Ho;Lee, Jong-Yeol;Lee, Sang-Seob
    • Korean Journal of Microbiology
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    • v.42 no.4
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    • pp.326-331
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    • 2006
  • In the present study, we examined biosorption characteristics of heavy metals onto the extracellular polysaccharide (EPS) produced by the purple nonsulfur photosynthetic bacteria Rhodopseudomonas sp. KH4, which was isolated from a stream in Anyang, Kyonggi-Do. When Cd (100 mg/L) and Cu (100 mg/L) were added to EPS (1.0 g/L) in the optimal condition (Cd; pH 8, Cu; pH 5, $40^{\circ}C$), 84.2 mg/L of Cd and 70.0 mg/L of Cu were adsorbed within 30 min and 10 min, respectively. When 100 mg/L of Cd and Cu were present as mixture, 16.8 mg/L of Cd and 48.7 mg/L of Cu were adsorbed at $25^{\circ}C$, pH 5. The maximum adsorption capacity determined by fitting Langmuir isotherms model was suitable for describing the biosorption of Cd (76.9 mg/g) and Cu (67.1 mg/g) by EPS. The neutral monosaccharide in the EPS determined by GC consisted of arabinose (2.4%), glucose (7.1%) and mannose (90.5%).

Effect of Spore-forming Eumycetes on the Chemical Change of Korean Ginseng Components -II. Spectroscopic Studies on Free Fatty Acid and Total Saponin in the Root of Panax ginseng C. A. Meyer- (포자형성진균류(胞子形成眞菌類)가 한국산(韓國産) 인삼성분(人蔘成分)의 화학적(化學的) 변화(變化)에 미치는 영향(影響) -제(第) 2 보(報): Panax ginseng C. A. Meyer의 뿌리에 존재(存在)하는 유리지방산(遊離脂肪酸)과 total saponin의 분광학적(分光學的) 연구(硏究)-)

  • Han, Kang-Wan;Nam, Chang-Woo;Jo, Jae-Sun;Oh, Sung-Ki
    • Korean Journal of Food Science and Technology
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    • v.13 no.3
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    • pp.209-218
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    • 1981
  • Free fatty acid and total saponin, which were extracted from the spent media and colony of the strain Phizopus delemar Rh-1, were qualitatively examined by GLC and spectroscopic methods and compared with these of intact ginseng media. The 18, 18, and 14 free fatty acids were respectively identified from the control, spent media and colony. Among them, $iC_{12:0},\;C_{16:2},\;C_{17:0},\;C_{18:3}\; and\;C_{20:0}$ acids were not detectable from the colony. In add ition, $C_{16:2}\;and\;C_{20:0}$ peaks were rot found in the spent media and control, respectively. The isible absorption spectra of free fatty acids and total saponins in the control, spent media and colony were invariable. In contrast, however, the infrared and ultraviolet absorption spectra showed significant spectral variations, particularly in the it finger-print region, demonstrating that the ginseng components were considerably utilized by the strain Rhizopus delemar Rh-1.

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Changes of Some Physicochemical Properties of Yoghurt made from ${\beta}$-Galactosidase-treated Commercial Milks (${\beta}$-Galactosidase 처리 시유로 제조한 요구르트의 이화학적 성분 변화)

  • Lee, In-Seon;Kim, Sang-Hee;Ha, Jae-Ho;Kang, Kook-Hee
    • Korean Journal of Food Science and Technology
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    • v.21 no.6
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    • pp.795-799
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    • 1989
  • This study was carried out to hydrolyze lactose in commercial milk by ${\beta}-galactosidase$ from Kluyveromyces fragilis and to compare some physicochemical properties of yoghurts made from control and lactase-treated commercial milks. Quantitative analysis of sugars was performed by gas liquid chromatograph (GLC) on trimethylsilyl (TMS) derivatives. In commercial milk, 94.6% of lactose was hydrolyzed after 2 hours incubation at $40^{\circ}C$ with 6.0 units/ml of ${\beta}-galactosidase$. pH, titratable acidity and viable cell number of yoghurt made from lactase-hydrolyzed (LH) commercial milk were 4.1, 1.04% and $6.5{\times}10^8/ml$ of Str. thermophilus, $8.9{\times}10^8/ml$ of L. bulgaricus after 8 hours incubation at $40^{\circ}C$, respectively, The total contents of amino acid were 2.63% in control and 2.19%. in LH yoghurt. The total contents of free amino acid were 26.95 mg% in control and 17.55mg% in LH yoghurt. Analysis of free fatty acids resulted in that the contents of short chain fatty acids in LH yoghurt were a little higher than those in control. Both in control and LH yoghurt, the palmitic acid content was highest and that was followed by oleic and myristic acid.

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The Formation of Trans Fatty Acids with Heat Treatment and Storage of Fats and Oils (II) -The contents and the kinds of Trans fatty acids- (유지의 가열 및 저장에 따른 Trans지방산 생성에 관한 연구 -제2보 ; Trans지방산 함량 및 조성 변화를 중심으로-)

  • Kim, Duk-Sook;Koo, Bon-Soon;Ahn, Myung-Soo
    • Korean journal of food and cookery science
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    • v.6 no.3 s.12
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    • pp.25-32
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    • 1990
  • In this study, the cis to trans isomerization of unsaturated fatty acids were investigated about Soybean oil (SBO), Corn germ oil (CGO), Cottonseed oil (CSO), Margarine (MG), Shortening (ST) incubated at $40{\pm}2^{\circ}C$ for 35 days and heated at $185{\pm}2^{\circ}C$ for 24 hours. The contents and kinds of trans fatty acids in each sample were determined by GLC after seperating by HPLC. The results were obtained as follows; 1. When samples were incubated at $40{\pm}2^{\circ}C$ for 35 days, the contents of total trans fatty acids were increased from $0.5{\sim}12.3%$ to $0.8{\sim}20.5%$. The kinds of trans fatty acids found were $t-C_{18:1},\;t,c-C_{18:2},\;t,t-C_{18:2},\;t,c,c-C_{18:3}$ in $SBO,\;t-C_{18:1},\;t,c-C_{18:2}$ in $CGO,\;t-C_{16:1},\;t-C_{18:1},\;t,c-C_{18:2},\;t,t-C_{18:2}$ in CSO. Processed oil such as MG and ST showed more complicated composition of trans fatty acids than SBO, CGO and CSO. $t-C_{18:1},\;t,c-C_{18:2},\;t,t-C_{18:2},\;t,c,t-C_{18:3},\;t-C_{20:1}$ were detected in ST. 2. In the case of heating at $185{\pm}2^{\circ}C$ for 24 hours, the contents of total trans fatty acid were $1.6{\sim}37%$. 2% in all samples. Heating made more remarkable isomerization than incubation $(40{\pm}2^{\circ}C)$. Specially, $c,c,t-C_{18:3}$ in $SBO,\;t,t,t-C_{18:3}$ in $MG,\;t,c,t-C_{18:3},\;t,t,t-C_{18:3}$ in ST were detected. 3. The total contents of trans fatty acids of processed oil were higher than vegetable oils. During incubation, trans fatty acids increased in the order of MG>ST>CGO>SBO>CSO, and during heat treatment, MG>ST>SBO>CGO>CSO.

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Residue analysis of insecticide thiodicarb in sweet persimmon and its safety evaluation (살충제 thiodicarb의 단감 중 잔류분석 및 안전성 평가)

  • Lo, Seog-Cho;Hwang, Cheol-Hwan;Kim, Min-Soo;Ma, Sang-Yong;Han, Seong-Soo
    • The Korean Journal of Pesticide Science
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    • v.8 no.3
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    • pp.184-188
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    • 2004
  • The residue analysis of the insecticide thiodicarb in sweet persimmon was analyzed with a gas chromatograph equipped with nitrogen phosphorus detector(NPD) to evaluate efficacy of analysis method and safety of thiodicarb in persimmon. Minimum detectable amount of methomyl oxime, hydrolysate of thiodicarb, was 0.2 ng and detection limit of thiodicarb was 0.05 ppm. The mean recoveries evaluated from untreated samples spiked at 0.5 ppm and 2.5 ppm were $93.9{\pm}3.9$ and $92.8{\pm}2.0%$, respectively. When thiodicarb was sprayed onto the sweet persimmon two times until 40 and 30 days before harvest, three times until 40, 30 and 21 days before harvest, and four times until 40, 30, 21 and 14 days before harvesting, the mean residual amount in sweet persimmon were $1.50{\pm}0.04$, $1.86{\pm}0.04$ and $2.11{\pm}0.12$ ppm, respectively. It would be safe when thiodicarb 40% WP is treated four times 14 days before harvesting to control fruit moth in sweet persimmon.

Inhibition of acetylcholinesterase activity by impurities in technical grades and purified flupyrazofos (Flupyrazofos 원제 및 정제품의 불순물 조성과 Acetylcholinesterase에 대한 저해 비교)

  • You, Kyoung-Youl;Cho, Boo-Yeon;Park, Dong-Sik;Hur, Jang-Hyun
    • The Korean Journal of Pesticide Science
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    • v.9 no.1
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    • pp.97-101
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    • 2005
  • Flupyrazofos (O,O-diethyl O-1-phenyl-3-trifluoromethylpyrazo-5-yl phosphorothioate) is an organophosphorus insecticide with a pyrazole moiety which is newly developed and commercialized by SUNGBO chemical company and Korean Research Institute of Chemical Technology for effectively control against diamond back moth. This study was conducted to determine the composition and quantity of impurities in technical 1 (94.5%), technical 2 (97.6%) and purified (99.2%) flupyrazofos using GLC/MSD. Bimolecular inhibition rate constant($k_i$) with acethylcholinesterase (in vitro) and $I_{50}$ with mouse brain acetylcholinesterase (in vivo) were measured for comparing inhibitory patterns of two technicals and purified flupyrazofos. Impurities of flupyrazofos were identified as O,O,O-triethylthio-phosphoric acid (TEA), 1-phenyl-3-trifluoromethyl-5-ethoxy pyrazole(PTMEP), O,O-diethyl O-1-phenyl-3-trifluoromethylpyrazo-5-yl phosphoric acid ester(flupyrazofos oxen), O,S-diethyl O-1-phenyl-3-trifluoromethylpyrazo-5-yl phosphorothionate (S-ethyl flupyrazofos). In in vitro, technical 1 showed the fastest inhibition on AChE activity among them. And technical 1 and 2 showed 40% higher in vivo inhibition against mouse brian AChE than purified flupyrazofos did. These results could be caused by the impurities such as flupyrazofos oxen and S-methyl flupyrazofos contained in technical grades of flupyrazofos.

Monitoring of Endocrine Disruptor-suspected Pesticide Residues in Greenhouse Soils and Evaluation of Their Leachability to Groundwater (시설재배 토양 중 내분비계장애 추정농약의 잔류 모니터링 및 지하수 용탈 가능성)

  • Noh, Hyun-Ho;Lee, Kwang-Hun;Lee, Jae-Yun;Park, Hyo-Kyung;Lee, Eun-Young;Hong, Su-Myung;Park, Young-Soon;Kyung, Kee-Sung
    • The Korean Journal of Pesticide Science
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    • v.15 no.4
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    • pp.441-452
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    • 2011
  • This study was carried out to survey the residual characteristics of endocrine disruptor (ED)-suspected pesticides in greenhouse soils and assess their leachabilites to groundwater. Greenhouse soils were collected from 40 sites of greenhouse in 2008 in Korea. Sixteen ED-suspected pesticides which had been using in Korea, such as alachlor, benomyl, carbaryl, cypermethrin, 2,4-D, dicofol, endosulfan, fenvalerate, malathion, mancozeb, metribuzin, metiram, methomyl, parathion, trifluralin, and vinclozolin, in the soils, were analyzed by chromatographic methods using GLC-ECD and HPLC-DAD/FLD. Limits of detection (LODs) of the test pesticides ranged from 0.0004 to 0.005 mg/kg. Recoveries of the target pesticides from soil ranged from 72.69 to 115.28%. Four pesticides including cypermethrin were detected in the range of from 0.001 to 2.019 mg/kg, representing that their detection rate from greenhouse soils was 37.5%. The highest detection rate was observed from endosulfan which was detected from 16 site soils of the total samples, indicating that endosulfan is persistent in soil because of its very low mobility and high adsorption characteristics in soil. Based on the groundwater ubiquity scores (GUSs) of the pesticides detected from greenhouse soils, most of them have little possibilities of groundwater contamination except the fungicide vinclozolin with some leaching potential because of high water solubility and very low soil adsorption property.

A Study on the Lipid Components in Oyster Mushroom (느타리버섯의 지방성분(脂肪成分)에 관한 연구(硏究))

  • Kwon, Yong-Ju;Uhm, Tai-Boong
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.13 no.2
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    • pp.175-180
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    • 1984
  • Lipids in oyster mushroom (Pleurotus florida) were extracted by the mixture of chloroform-methanol (2: 1, v/v) and fractionated into neutral lipids, glycolipids and phospholipids by silicic acid column chromatography. Components and fatty acid composition of each fraction were deter- mined by thin-layer and gas-liquid chromatographies. Fresh oyster mushroom contained 0.5% total lipid in which the contents if neutral lipids, glycolipids and phospholipids were 33.8%, 19.7% and 45. 6%, respectively, Triglycerides(38.2%), free fatty acids (20%) and free sterol (10%) were the major components among the neutral lipids. Diglycerides, monoglycerides, sterol esters and three unidentified neutral lipids were the minor components. Major components of glycolipids were steryl glycosides(35.9%) and esterified steryl glycosides (23.7%). Digalactosyl diglycerides, mono-galactosyl diglycerides and two unknown components were also present. Of the phospholipids, phosphatidyl cholines and serines (48.2%), and phosphatidyl ethanolamines(44.4%) were the major components. On the other hand, the major fatty acids of neutral lipids we.e linoleic, palmitoleic, oleic and palmitic acid. Linoleic and palmitic acid were the predominant fatty acids of both glycolipids and phospholipids.

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