• 한국환경농학회지
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• 제27권3호
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• pp.279-284
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• 2008

We investigated whether carboxylate exudation of Brassica pekinensis Rupr. was affected by nitrate deposition from simulated acid rain. A gas chromatographic (GC) analysis was employed for the determination of low molecular weight organic acids (LOA) in rhizosphere soils, bulk soil, roots and leaves of Brassica pekinensis Rupr.. Rhizosphere soils were collected after 8 weeks of plant growth by first removing the bulk soil from the root system and then by mechanical move off the rhizosphere soil that adhered to the root surface with soft brush. Soil and plant materials were simultaneously extracted with the mixture of methanol and sulfuric acid (100:7, v/v). Seven organic acids, oxalic, malonic, fumaric, succinic, maleic, L-malic and citric acid were identified and quantified by GC equipped with FID. Oxalic, L-malic, and citric acids were found in both the bulk and rhizosphere soils, while most LOAs were not detected in the control treatment. On the contrary, except maleic acid, all other organic acids were detected in the leaves and roots of cabbages treated with nitrate deposition.

• 생약학회지
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• 제32권3호통권126호
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• pp.200-211
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• 2001

This study was carried out to determine the 11 organochlorine, 7 organophosphorus residual pesticides in 251 crude drugs. These residual pesticides in herbal drugs were extracted with acetonitrile and the extracts were cleaned up via LC-florisil solid phase extraction column. The prepared samples were assayed for pesticide residues using GC-ECD, NPD with capillary column and identified by GC-MSD. Recoveries were $63.9{\sim}111.5%$ in the organochlorine pesticides and $69.8{\sim}92.4%$ in the organophosphorus pesticides, and detection limits were $0.001{\sim}0.65\;ppm$ in the organochlorine pesticides and $0.0009{\sim}0.0074\;ppm$ in the organophosphorus pesticides. Pesticide residues were detected in 9 cases.

• 한국동물위생학회지
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• 제22권1호
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• pp.15-23
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• 1999

A multiresidue, simple and rapid isolation technique known as matrix-solid phase dispersoin (MSPD) for the extraction and quantitative gas chromatographic/electron capture detection (GC/ECD) determination of 14 organochlorinated pesticides($\alpha$-BHC, ($\beta$-BHC, ($\gamma$-BHC, aldrin, dieldrin, endrin, heptachlor, ($\alpha$-endosulfan, ($\beta$-endosulfan, endosulfan sulfate, p,p'-DDE, o,p'-DDD, p,p'-DDD, p,p'-DDT) from meat fats. The 14 pesticide were fortified into meat fat(0.5g) and blend with 2g $C_{18}$, $C_{18}$meat fat matrix blend and 2g activated florisil comprise an extraction column from which the pesticides are eluted by adding 8ml acetonitrile. Then 2${\mu}\ell$ of the eluate is analyzed by GC/ECD. Unfortified blank controls are tested similarly. The eluate contained all the pesticide analytes and was free of interfering coextractants. Recovery rate(31.3-500ng/g) were ranged from 80$\pm$4% to 97$\pm$4%. Any organochlorinated pesticides were not detected in 120 samples of beef and pork collected from slaughter houses in Kyeonggi province.

• 한국식품조리과학회지
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• 제8권3호
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• pp.247-253
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• 1992

The total dietary fiber (TDF) contents in cultivated dodok, wild dodok and ginseng were determined by AOAC method and Mongeau et al's method. Also, the nonstarch polysaccharide (NSP) contents of them were analyzed by Englyst et al's gas chromatographic (GC) method. The TDF values by AOAC method and Mongeau et al's method were 34.50% and 35.92% for wild dodok, 46.40% and 47.55% for cultivated dodok, and 14.93% and 14.03% for ginseng, respectively. The ratios of soluble dietary fiber (SDF) contents to TDF contents by Mongesu et al's method were 64.17% for wild dodok, 75.77% for cultivated dodok, and 53.74% for ginseng, respectively. The major sugar constituents of NSF in wild dodok, cultivated dodok and ginseng by GC were glucose, galactose and uronic acid. The Enalyst's TDF contents, i.e., NSP plus lignin contents in wild dodok, cultivated dodok, and ginseng were 20.65%, 20.03% , and 9.72%, respectively.

• 대한화학회지
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• 제41권2호
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• pp.105-112
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• 1997

건어물 중의 냄새나는 질소화합물을 증류동시 추출법으로 추출하여 GC-MS로 분석하였다. Amine의 equivalent chain length를 구하여 머무름시간으로부터 탄소수와 차수를 예측할 수 있었다. 새우, 멸치, 북어, 대구, 오징어, 문어, 쥐포, 병어포, 홍합, 조갯살 등 우리 나라에서 많이 식용되는 시료를 분석대상으로 하였다. Dimethylamine, trimethylamine, diethylamine 등은 건어물에서 검출되지 않았으나 methylamine, acetamide, thiazole, 2-hydroxy isopropylamine, N-methyl pyrroline, cyclohexylamine 같은 냄새나는 질소화합물들이 GC-MS로 확인되었다. 건어물의 냄새패턴을 식별하기 위하여 GC-MS 피크면적을 자료로 주성분분석을 적용하였다. 주성분분석에 의한 다변량해석은 건어물의 냄새패턴의 유사성과 이질성의 식별에 유익하다는 결론을 얻었다.

• Toxicological Research
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• 제25권1호
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• pp.41-45
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• 2009

This study was conducted to monitor the level of bifenthrin residues in pear sprayed with 2% bifenthrin wettable powder (WP) at the recommended rate at four different schedules prior to harvest. The target analyte was extracted with acetone, partitioned into dichloromethane, and then purified by florisil chromatographic column. The residue determination was performed on a DB-5 capillary column using GC with electron capture detector (ECD). Linearity of this method was quite good ($r^2$ = 0.9951) in the concentration ranged from 0.2 mg/kg to 10 mg/kg. Recovery test was carried out at two concentration levels, 0.2 mg/kg and 1.0 mg/kg, in three replicates, and their rates were from 82.9% to 107.2%. No quantitative bifenthrin was detected in pear of all kinds of treatments including the treatment sprayed 4 times until 7 days before harvest. This sensitive and selective method can be used to monitor the trace residual amounts of bifenthrin in pear in a quite low concentration level.

• 한국근적외분광분석학회:학술대회논문집
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• 한국근적외분광분석학회 2001년도 NIR-2001
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• pp.3114-3114
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• 2001

During the last years phytochemistry and phytopharmaceutical applications have developed rapidly and so there exists a high demand for faster and more efficient analysis techniques. Therefore we have established a near infrared transflectance spectroscopy (NIRS) method that allows a qualitative and quantitative determination of new polyphenolic pharmacological active leading compounds within a few seconds. As the NIR spectrometer has to be calibrated the compound of interest has at first to be characterized by using one or other a combination of chromatographic or electrophoretic separation techniques such as thin layer chromatography (TLC), high performance liquid chromatography (HPLC), capillary electrophoresis (CE), gas chromatography (GC) and capillary electrochromatography (CEC). Both structural elucidation and quantitative analysis of the phenolic compound is possible by direct coupling of the mentioned separation methods with a mass spectrometer (GC-MS, LC-MS/MS, CE-MS, CEC-MS) and a NMR spectrometer (LC-NMR). Furthermore the compound has to be isolated (NPLC, MPLC, prep. TLC, prep. HPLC) and its structure elucidated by spectroscopic techniques (UV, IR, HR-MS, NMR) and chemical synthesis. After that HPLC can be used to provide the reference data for the calibration step of the near infrared spectrometer. The NIRS calibration step is time consuming, which is compensated by short analysis times. After validation of the established NIRS method it is possible to determine the polyphenolic compound within seconds which allows to raise the efficiency in quality control and to reduce costs especially in the phytopharmaceutical industry.

• Bulletin of the Korean Chemical Society
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• 제24권4호
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• pp.413-420
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• 2003

A gas chromatography/mass spectrometric assay method was developed for the simultaneous determination of neutral and bacis twenty-five disruptors $(ED_S)$ in frog and fish. Afther homogenization and sonication of 5 g of sample, purification was achieves in one step with a solid phase extraction procedure using silica gelflorisl. Eluton was performed with 50mL of acetone : n-hexane (1 : 9) solution. The eluate was concentrated to approximately 10uL and dissolves with 100 uL of hexane and analyzed by GC-MS (SIM). The peaks had good chromatographic properties and the extraction of these compounds from sample also gave relatively high recoveries with small variatoins. Detection limits were 0.1 ng/g for 4-nitrotoluene, benzophenone, hexachlorobenzene, atrazine, malathion, o,p-DDT, o,p-DDT and permethrin, and 0.2 ng/g for heptachlor epoxide, γ-chlordane, α-chlordane, p,p'-DDE, p,p'-DDD, cypermethrin and fenvalerate, and 0.3 ng/g for trifluralin, metribuzin, alachlor, dieldrin and p,p'-DDT, and 0.5 ng/g for heptachlor, aldrin and parathion, and 0.7 ng/g for endrin, and 0.8 ng/g for nitrofen. The recoveries were between 33 and 109%. The method was used to analyze twenty-five frogs and forty-six fishes fishes samples caught from various regions in Korea. Benzophenone was detected at concentration of up to 17.2 ng/g in frog or fish. Heptachlor, aldrin, γ-chlordane, p,p'-DDE, p,p'-DDD, endrin and o,p-DDD were detected at concentrations of 0.7-12.5 ng/g in frog or fish. Also significant leveles of dieldrin (up to 22.5 ng/g) were observed. The developed method may be valuable to be used to the national monitoring project of EDS in biota samples.

• Bulletin of the Korean Chemical Society
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• 제28권3호
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• pp.432-438
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• 2007

Environmentally important phthalic esters have been analyzed by GC-MS in terms of individual phthalic esters or total phthalic esters directly or after derivatization. Derivatization improves the chromatographic characteristics of the highly polar phthalic esters. This study focused on the GC-MS determination of the total phthalic esters and the individual phthalic esters simultaneously. The phthalic esters were hydrolyzed to phthalate and corresponding alcohols in 1 M NaOH solution at 90 oC for 30 min followed by extraction with ethyl acetate after acidifcation. The phthalic acid and alcohols were simultaneously silyl derivatized using bis(trimethylsilyl)trifluoroacetamide (BSTFA) to their corresponding silyl ester and ethers in the mixture of 60% acetone and 40% ethyl acetate at room temperature within 30 min. Because of the high reactivity of BSTFA with the phthalic acid and alcohols effective silyl derivatization was possible simultaneously. GC-MS analysis of the silyl derivatives of phthalic acid and alcohols was performed. The total phthalic ester content was estimated from the analytical result of phthalic silyl ester, while the individual phthalic ester was quantified from the analytical results of alcoholic silyl ethers. This technique was applied to spiked tab water and real seawater samples from the Lake Shihwa in Korea. The results were checked against the results from the direct GC-MS analysis of the phthalic esters and reasonable recoveries with high sensitivity were achieved. The recoveries were higher than 75% with low relative standard deviation (below 10%).

• 생명과학회지
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• 제14권2호
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• pp.221-224
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• 2004

일반적으로 오징어의 콜레스테롤 함량은 높다고 보고하고있지만, 이는 주요 가식부인 몸통육에 대한 것이고, 여타 스테롤도 함께 정량하는 비색법에 의한 정량 결과인 경우가 많아 신뢰하기 힘들다. 그리고 이런 단점을 개선한 효소법이나 GC법은 모두 다 또 다른 단점인 고가 효소 키트가 필요하다던가 복잡한 전처리가 필요하다던가 하여 적용하기가 쉽지 않다. 따라서, 오징어 몸통 이외의 새로운 가식부로 이용되고 있는 껍질부, 내장이나 간장부위 등에는 얼마만큼의 콜레스테롤이 함유되어 있는지 정량해 보고 아울러 기존 효소법이나 GC법의 단점을 모두 극복한 Iatroscan법에 의한 콜레스테롤 정량을 시도 확립해 보았다. 또한, 이 방법의 확립을 위해 필요한 오징어 부위별 수분함량과 지방함량 및 지방종 분석도 동시에 행하였다. 한국산 물오징어 중의 부위별 수분 및 지방함량에 있어서 간장부위가 각각 50.4%, 15%로서 다른 부위와 큰 차이를 보였고, 다른 부위는 각각 75.8∼83.6%, 1.9∼4.7% 수준으로서 큰 차이는 없었다. Iatroscan법에 의한 콜레스테롤 정량을 위한 근거가 되는 지방종 조성비에 있어서는 간장부위는 92.1%가 중성지방으로서 주성분을 이루고 있었고, 몸통육과 다리육이나 껍질부위는 인지질이 81.2∼87.9%%로서 주성분이었다. 5$\alpha$-cholestane을 내부표준물질로한 Iatroscan법에 의한 콜레스테롤 정량 결과 기존의 효소법과 GC법에 의한 수치와 큰 차이를 보이지는 않아 가장 간단히 콜레스테롤을 정량해 내는 법으로 사용할 수 있다고 판단되었다. 즉, Iatroscan법으로 오징어 부위별 콜레스테롤을 정량한 결과 오징어 간장 부위에 643.2 mg%, 껍질에 608.8 mg%, 다리육에 321.4 mg%, 눈 부위에 159.5 mg%, 주가식부인 몸통육에 178.9 mg% 수준으로 콜레스테롤이 함유되어 있었다.