• Title/Summary/Keyword: Gas Chromatography/mass spectrometry

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Determination of benzene, toluene, ethylbenzene and o-xylene in bottled waters by headspace solid-phase microextraction and gas chromatography/mass spectrometry (HS-SPME-GC/MS를 이용한 먹는 샘물 중 벤젠, 톨루엔, 에칠벤젠, 자일렌의 정량)

  • Kim, Jong-Hun
    • Analytical Science and Technology
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    • v.24 no.2
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    • pp.119-126
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    • 2011
  • Abstract: The amount of benzene, toluene, ethylbenzene, and o-xylene (BTEX) in 30 kinds of bottled waters purchased from market and 9 kinds of tap waters from home were determined using headspace solid phase microextraction (HS-SPME). The sample was stirred at 1200 RPM G for 4 min using a magnetic bar with $100\;{\mu}m$ PDMS as adsorbent for BTEX. Then it was desorbed from the fiber for 1 min at room temperature. Quantitation was achieved using standard calibration method. The limit of detection was determined as benzene 0.39 (${\pm}0.04$) ng/mL, toluene 0.08 (${\pm}0.04$) ng/mL, ethylbenzene 0.04 (${\pm}0.01$) ng/mL, and o-xylene 0.05 (${\pm}0.02$) ng/mL. Benzene and o-xylene were not detected in any samples, but toluene was detected in 11 samples, and ethylbenzene was detected just in 3 samples among 30 investigated bottled waters. The concentration range of investigated materials for toluene and o-xylene were $0.24({\pm}0.09)\sim2.95\;({\pm}0.08)\;ng/mL$, $0.08({\pm}0.06)\sim0.93({\pm}0.10)\;ng/mL$, respectively.

Analysis of radiation induced hydrocarbons by electron-beam irradiation in dried squid (Todarodes pacificus) and octopus (Paroctopus dofleini) (전자선 조사한 건조된 오징어와 문어에서 유도된 지방분해산물의 분석)

  • Hong, Young Shin;Ryu, Keun Young;Kim, Kyong Su
    • Food Science and Preservation
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    • v.21 no.3
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    • pp.381-387
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    • 2014
  • Food irradiation is one of the successful modern techniques used to preserve food. However, it needs very careful control. Detection of irradiated food is of prime importance to facilitate global trade and consumer assurance, choice, and protection. This study was performed to evaluate the radiation-induced hydrocarbon content of dried squid and octopus by e-beam irradiation. The samples were collected from supermarkets all over South Korea and irradiated with an e-beam at 0, 1, 3, 5, 7, and 10 kGy doses. Lipids were extracted with soxhelt, and the hydrocarbons induced with irradiation were separated via solid phase extraction (SPE) and identified via gas chromatography mass spectrometry (GC/MS). The major induced hydrocarbons in the irradiated dried squid and octopus were 1-tetradecene and pentadecane derived from palmitic acid and 1-hexadecene and heptadecane from stearic acid. The concentration of hydrocarbons differed from the composition of the fatty acid at the same radiation and increased according to the level of the radiation dose. The hydrocarbons induced by e-beam irradiation, including 1-tetradecene, 1-hexadecene, and heptadecane, were confirmed to have been the irradiation marker compounds. Therefore, they can be used to distinguish the e-beam-irradiated dried squid and octopus from the non-irradiated ones.

Synthesis and Isolation of Monoacetyl-DCB and Diacetyl-DCB from 3,3대-dichlorobenzidine(DCB) (디클로로벤지딘으로부터 대사물질의 합성과 분리방법에 대한 연구)

  • Lee, Jin-Heon;Lee, Beom-Gyu
    • Journal of Environmental Health Sciences
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    • v.29 no.2
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    • pp.50-55
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    • 2003
  • 3,3-dichlorobenzidine is suspected to be cancinogenic in experimental animal and human. Several studies have investigated excretion of metabolites in urine, hemoglobin adduction and cancer incidence among workers occupationally exposed to 3,3'-dichlorobenzidine. In these researches, metabolites of 3,3'-dichlorobenzidine had a very important role, and were required as highly purity. The purpose of this study was synthesis and isolation of its metabolites from 3,3'-dichlorobenzidine. 3,3'-dichlorobenzidine was partially dissolved in benzene, ether, ethanol and methanol, and completely dissolved in 70% acetic acid on mixtures of citric acid containing less than 1% DCB, pyridine, a mixture of 0.5N NaOH and toluene(1:2), and phenol saturated with 20 mM TRIZA base. DCB, monoacetyl-DCB and diacetyl-DCB were measured by using gas chromatography/mass spectrometry(GC/MS). Detection for checking them was nitrogen phosphorous detection mode(NPD), and for identifying them was selected ion monitoring mode(SIM). The base peaks were 252 m/z in DCB, 252, and 294 m/z in monoacetyl-DCB, and 252, 294 and 336 m/z in diacetyl-DCB, respectively. Diacetyl-DCB was synthesized by titrating DCB solution of pyridine with sufficient acetyl chloride. Precipitation was diacetyl-DCB, which was purity of 98.7%. And its supernatant was composed of DCB, monoacetyl-DCB and diacetyl-DCB. By using acetic acid as controller of acetylation, monoacetyl-DCB was isolated from diacetyl-DCB . And residual pyridine was removed by using acetone. The purity of monoacetyl-DCB was 98.8%.

Gastric Stump Cancer (잔위암)

  • Oh Young Seok;Kim Young Sik;Sin Yeon Myung;Lee Sang Ho;Moon Yeon Chang;Choi Kyung Hyun;Chung Bong Churl
    • Journal of Gastric Cancer
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    • v.1 no.3
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    • pp.144-149
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    • 2001
  • Purpose: Gastric stump cancer is defined as a cancer that develops in the stomach after a resection in cases of non-malignant or malignant gastric disease. The interval between the gastrectomy and the detection of gastric stump cancer must be over 5 years. Since duodenogastric reflux gastritis is a precancerous condition and one of the most important factors inducing gastric stump cancer, we compared the bile-acid content of gastric juice between gastric stump cancer patients and controls. Materials and Methods: To evaluate retrospectively the surgical treatment of patients with gastric stump cancer, we reviewed the cases histories of 1016 stomach cancer patients who had been operated on at the Department of General Surgery, Kosin University Gospel Hospital, between 1995 and 1998. The gastric juice was collected during the operations on the gastric stump cancer patients by using a needle puncture of the fundus of the stomach and during the endoscopic examinations of the control subjects. The samples were analyzed for various bile acids (gas chromatography/mass spectrometry). Results: The 6 gastric stump cancer cases accounted for $0.6\%$ of all gastric cancer patients; 5 patients were first operated on for a peptic ulcer and the remaining one for an adenocarcinoma of the stomach. All of the cases were men. The reconstruction method after the initial gastrectomy was a Billroth II in all cases. The sites of the gastric stump cancer were the anastomotic sitein 2 patients, the upper body in 2, the fundus in 1 and the cardia in 1. The operative methods were 3 total gastrectomies, 2 subtotal gastrectomies with Roux en Y anastomosis, and 1 partial gastrectomy with lymph node dissection and had a curative intention in all patients. All of the patients were still surviving at the time of this report. The gastric juices of 4 gastric stump patients showed significantly higher contents of cholic acid ($36.42{\mu}g/ml$) compared to the gastric juices of 35 control subjects ($36.42{\mu}g/ml$)(p$\leq0.0001$). Chenodeoxycholic acid and lithocholic acid were not significantly different. Conclusion: The gastric juice of gastric stump cancer patients contained a significantly higher cholic acid content. At the time of the initial gastrectomy, an operative method that prevents duodenogastric reflux may prevent or minimize the development of gastric stump cancer, and more aggressive surgical treatment may improve survival.

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Volatile Components of Pine Needle(Pinus densiflora S.) by Purge and Trap Headspace (Purge and Trap Headspace 법에 의한 솔잎(Pinus densiflora S.)의 휘발성 성분)

  • Lee Jae-Gon;Lee Chang-Gook;Jang Hee-Jin;Kwag Jae-Jin
    • The Korean Journal of Food And Nutrition
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    • v.17 no.3
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    • pp.260-265
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    • 2004
  • Volatile components of pine needle(Pinus densiflora S.) were isolated by purge & trap headspace technique and analyzed by gas chromatography-mass spectrometry(GC-MS). And then volatile components were extracted for 2 hr and 20 hr at the two different temperature settings: room temperature and 60$^{\circ}C$. A total of 61 volatile components were identified by the four different conditions. These compounds are classified into six categories in terms of chemical functionality: 35 hydrocarbons, 16 alcohols, 4 carbonyls, 2 esters, 1 acid and 3 ethers. The major components were ${\alpha}$-pinene(1.5~15.7%), ${\beta}$-myrcene(13.2~15.6%), ${\beta}$-phellandrene(l2.0~16.0%) and cis-3-hexenol(4.0~18.3%). In the comparison of the four extraction conditions, longer extraction can be effective to extract components that have a high boiling point, but proved useless in obtaining low boiling point components. As a result of these experiments under the four different conditions, the 20 hr extraction at room temperature appeared to be the most optimized condition for the analysis of volatile compounds by using the purge & trap headspace technique.

Volatile Constituents by Treatment of Artificial Saliva in Fresh Ginseng Root (인공타액처리에 의한 수삼의 향기성분 변화 분석)

  • In, Jun-Gyo;Kwon, Woo-Sup;Min, Jin-Woo;Lee, Bum-Soo;Kim, Eun-Jeong;Yang, Deok-Chun
    • Journal of Ginseng Research
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    • v.32 no.4
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    • pp.305-310
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    • 2008
  • The volatile constituents of the fresh roots of Panax ginseng C.A. Meyer have been investigated after treatment with artificial saliva and analysed by gas chromatography-mass spectrometry (GC-MS) using solid phase microextraction (SPME) fiber. Twenty peaks were detected in fresh ginseng, 5 of them were unknown peak, and mainly hydrocarbon components (${\alpha}$-pinene, ${\beta}$-pinene, myrcene, limonene, ${\beta}$-panasinsene, ${\beta}$-elemene, ${\beta}$-gurjunene, trans-caryophyllene, ${\alpha}$-gurjunene, ${\alpha}$-panasinsene, ${\alpha}$-neoclovene, trans-${\beta}$-farnasene, ${\alpha}$-humulene, ${\beta}$-neoclovene, ${\alpha}$-selinene, ${\beta}$-selinene, bicyclogermacrene) were detected. It's area percentage was increased about 10% in the fresh ginseng added artificial saliva during 40 minutes.

Comparative Evaluation of the Analytical Methods used to Determine Pesticide Residues in Milk via Dispersive Solid Phase Extraction (Dispersive Solid Phase Extraction을 사용한 우유 내 잔류농약 다성분 동시 분석법 비교연구)

  • Oh, Nam Su;Shin, Yong Kook;Lee, Ji Young;Baick, Seung Chun
    • Journal of Dairy Science and Biotechnology
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    • v.33 no.1
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    • pp.27-34
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    • 2015
  • The aim of this study was to optimize a simple, fast, and economic analytical method for the simultaneous determination of various pesticides (aldrin, p,p'-DDT, o,p'-DDT, p,p'-DDE, ${\alpha}$-endosulfan, ${\beta}$-endosulfan, dieldrin, heptachlor, permethrin, chlordane, deltamethrin, diazinon, bifenthrin, methoprene, propargite, fenpropathrin, cypermethrin, fenvalerate, and fenpropathrin) in milk by using dispersive solid phase extraction (SPE). In this study, two different extraction methods (low temperature cleanup and liquid-liquid partitioning), which were followed by a cleanup process based on dispersive-SPE, were evaluated and compared for the 19 pesticides. The results for all the pesticides were determined by gas chromatography mass spectrometry (GC/MS) with selected-ion monitoring mode, and the matrix effect of the method was evaluated. Comparison of these approaches yielded higher and more consistent recoveries of most pesticides at fortification levels of $1{\mu}g/mL$ using low-temperature fat precipitation, followed by cleanup process based on dispersive-SPE with PSA and C18 as sorbents, than other preparation process. The relative standard deviation was <20 % and the combination of this method were very effective for the cleanup.

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Fragrance, Chemical Composition and Toxicity of the Essential Oil in Erect Bur-marigold (Bidens tripartita L.) (가막사리 (Bidens tripartita L.) 정유의 향취, 화학성분 및 세포독성)

  • Yun, Mi-Sun;Yeon, Bo-Ram;Cho, Hae-Me;Lee, Sa-Eun;Jhoo, Jin-Woo;Jung, Ji-Wook;Park, Yu-Hwa;Kim, Song-Mun
    • Korean Journal of Weed Science
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    • v.32 no.3
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    • pp.195-203
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    • 2012
  • The essential oil was extracted by steam distillation from the aerial part of erect bur-marigold (Bidens tripartita L.), one of the noxious weed in paddy field. The composition of the essential oil was analyzed by gas chromatography-mass spectrometry. The fragrance of the essential oil was green, herbal, oily, spicy. There were 42 constituents in the essential oil:17 hydrocarbons, 6 alcohols, 6 acetates, 5 N-containing compounds, 3 ethers, 3 ketones, 1 lactone and 1 S-containing compound. Major constituents were ${\alpha}$-phellandrene (22.50%), ${\alpha}$-pinene (22.21%), 2,4-dimethyl (2,5-dimethylphenyl) methyl ester benzoic acid (15.11%), limonene (10.66%), ${\beta}$-pinene (35.43%), and ${\beta}$-cubebene (5.27%). The $IC_{50}$ value in MTT assay using HaCaT keratinocyte cell line was 0.018%. However, attachment of patch with 0.1% of the erect bur-marigold essential oil for 24 hr did not show any skin toxicity. Overall results of this study suggest that the essential oil of erect bur-marigold could be used as a source for the development of perfumery industrial products.

Validity Assessment of Self-reported Smoking Status: Results from the Korean National Environmental Health Survey (KoNEHS) 2009-2011 (흡연상태에 관한 자가보고 설문의 타당도 평가: 제1기(2009-2011) 국민환경보건기초조사 자료 분석)

  • Choi, Wookhee;Park, Kyung Hwa;Kim, Hyun Jeong;Ryu, Jungmin;Yu, Seung Do;Choi, Kyunghee;Kim, Suejin
    • Journal of Environmental Health Sciences
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    • v.40 no.6
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    • pp.492-501
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    • 2014
  • Objectives: The purpose of this study was to assess the validity of self-reported cigarette smoking status and investigate factors associated with the accuracy self-reported and measured urinary cotinine in Korean adults. Methods: We used data from the $1^{st}$ Korean National Environmental Health Survey (2009-2011) among adults aged ${\geq}19$ years (N=6,246). The survey examined self-reported smoking status, and urinary cotinine was regarded as the biomarker of exposure to tobacco smoke. Urinary cotinine was analyzed using a gas chromatography-mass spectrometry (GC/MS) and data analysis was conducted using IBM SPSS version 20.0, which uses the sample weight and calculates variance estimates to adjust for the unequal probability of selection into the survey. Results: We calculated a cut-off point (53.3 ug/L) by using a ROC (Receiver Operating Characteristic) curve. The smoking prevalence was 24.6% based on self-reported data and 28.2% based on urinary cotinine concentrations. When we assessed the agreement between self-reported and urinary cotinine, we found an average agreement of 97.7% among self-reported smokers and 94.5% among self-reported non-smokers. Among self-reported smokers, factors affected the discrepancy were age, household economic status and average number of cigarettes smoked per day. On the other hand, gender, former smoking experience, and exposure to SHS (second hand smoke) were associated with discrepancies among self-reported non-smokers. Conclusion: These results suggest that self-reported data on smoking status provide a valid estimate of actual smoking status. In future research, we will conduct a continuous monitoring study for reliability verification of the data to reduce potential interpretation errors.

Irradiation-induced Volatile Compounds in Irradiated Chicken by P&T Method (P&T법에 의한 닭고기의 방사선 유래 휘발성 조사물질 구명)

  • Kim, Hun;Cho, Woo-Jin;Jung, Yeon-Jung;Lee, Young-Mi;Jeong, Eun-Jeong;Yoo, Young-Jae;Byun, Myung-Woo;Cha, Yong-Jun
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.31 no.6
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    • pp.958-964
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    • 2002
  • To select the irradiation-induced marker components from volatile flavor compounds in irradiated chicken, and complement the extraction problems of liquid continuous extraction (LLCE) method, the volatile compounds of irradiated (0,1,3,5 and 10 kGy) chicken were analyzed by Purge and Trap (P&T) and gas chromatography/mass spectrometry (GC/MS) methods. A total of 119 compounds were detected in irradiated chicken, and these compounds were composed mainly of 7 aldehydes,22 ketones,8 alcohols,30 esters,36 hydrocarbons,8 aromatic compounds and 8 miscellaneous compounds. Among these, only 21 compounds were detected in both LLCE and P&T methods, and the 98 other were detected in omly P&T method. Among volatile compounds detected in irradiated chicken, only 3 compounds such as hexene (r=0.96, p<0.01), propanol (r=0.93, p<0.05) and 1,3-bis(1,1-dimethylethyl) benzene (r=0.96, p<0.05) were newly selected as marker compounds in irradiated chicken by P&T method, which showed significant and high positive correlation coefficient in the change of relative concentration according to the increment of irradiation dosage.