• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2005.04a
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• pp.199-201
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• 2005

This paper describes a simple procedure for the quantitative analysis of 7 PCBs (polychlorinated biphenyls) in soils on the waste reclaimed land, The procedure involved sample clean up using silicagel column, acetonitrile partition and sulfuric acid procedures. The instrumental technique is applied GC/PDD(gas chromatography/pulsed discharge detector) and GC/ECD(gas chromatography/electron capture detector). Concentration of $sub-{\mu}g/g$ level was attainable with 20g soils on the waste reclaimed land.

• Journal of the Korean Society of Tobacco Science
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• v.16 no.1
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• pp.20-25
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• 1994

The volatile components were extracted from root of Cnidium officinale M. by SDE(Simultaneous steam distillation and extraction) apparatus and analyzed by GC/M.5 and GC retention index matching. The experimental results revealed the presence of over 22 volatile components. Major components were cnidilide (35.1%), neocnidilids (13.4%), ligustilide (23.2%). The essential oils were separated by silica gel column chromatography(Merck 70-230mesh), and 4 fractions among 12 fractions separated had a, good aroma character.

• Korean Journal of Food Science and Technology
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• v.35 no.1
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• pp.144-148
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• 2003

Volatile components were detected from domestic and imported Angelica gigas Nakai without any pretreatment using GC based on Surface Acoustic Wave (SAW) sensor. This system produced a frequency proportional to the amount of column effluent deposited on the SAW sensor. Discrimination between domestic and imported Angelica gigas Nakai was achieved through recognition of visual pattern using $VaporPrint^{TM}$ derived from frequency and chromatogram of GC-SAW sensor.

• Korean Journal of Food Science and Technology
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• v.20 no.2
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• pp.176-187
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• 1988

Volatile flavor components in the Chinese quince fruits were trapped by simultaneous steam distillation-extraction method, and these were fractionated into the neutral, the basic, the phenolic and the acidic fraction. In the identification of carboxylic acids, the acidic fraction was methylated with diazomethane. Volatile flavor components in these fractions were analyzed by the high-resolution GC and GC-MS equipped with a fused silica capillary column. The total of one hundred and forty-five compounds from the steam volatile concentrate of the Chinese quince fruits were identified: they were 3 aliphatic hydrocarbons, 1 cyclic hydrocarbon, 4 aromatic hydrocarbons, 9 terpene hydrocarbons, 17 alcohols, 3 terpene alcohols, 6 phenols, 21 aldehydes, 7 ketones, 28 esters, 27 acids, 3 furans, 2 thiazoles, 2 acetals, 3 lactones and 9 miscellaneous ones. The greater part of the components except for carboxylic acids were identified from the neutral fraction. The neutral fraction gave a much higher yield than others and was assumed to be indispensable for the reproduction of the aroma of the Chinese quince fruits in a sensory evaluation. According to the results of the GC-sniff evaluation, 1-hexanal, cis-3-hexenal, trans-2-hexenal, 2-methyl-2-hepten-6-one, 1-hexanol, cis-3-hexenol, trans, trans-2, 4-hexadienal and trans-2-hexenol were considered to be the key compounds of grassy odor. On the other hand, esters seemed to be the main constituents of a fruity aroma in the Chinese quince fruits.

• Korean Journal of Food Science and Technology
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• v.32 no.3
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• pp.513-518
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• 2000

Volatile flavor components of Angelica gigas Nakai affected by different storage time and temperature were investigated. The aroma compounds was extracted by a simultaneous distillation and extraction method using a Likens and Nickerson's apparatus. The concentrated extract was analyzed and identified by GC and GC-MS equipped polar and nonpolar column. The yields of volatile concentrates of Angelica gigas Nakai by low temperature storage were larger than those by room temperature storage. The GC patterns of the flavor components of both resembled but the peak area of each flavor compounds was little different. Main volatile flavor components of Angelica gigas Nakai by using polar column were ${\alpha}-pinene$, ${\beta}-pinene$, terpineol, farnesol, cadinene, guaiol, isolongifolene and eudesmol etc. Main volatile flavor components of Angelica gigas Nakai by using nonpolar column were camphene, ${\beta}-pinene$, elemol, eudesmol etc.

• Korean Journal of Environmental Agriculture
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• v.29 no.2
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• pp.165-175
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• 2010

A gas chromatographic (GC) method was developed to determine residues of captan, folpet, captafol, and chlorothalonil, known as broad-spectrum protective fungicides for the official purpose. All the fungicide residues were extracted with acetone containing 3% phosphoric acid from representative samples of five agricultural products which comprised rice, soybean, apple, pepper, and cabbage. The extract was diluted with saline, and dichloromethane partition was followed to recover the fungicides from the aqueous phase. Florisil column chromatography was additionally employed for final cleanup of the extracts. The analytes were then determined by gas chromatography using a DB-1 capillary column with electron capture detection. Reproducibility in quantitation was largely enhanced by minimization of adsorption or thermal degradation of analytes during GLC analysis. Mean recoveries generated from each crop sample fortified at two levels in triplicate ranged from 89.0~113.7%. Relative standard deviations (RSD) were all less than 10%, irrespective sample types and fortification levels. As no interference was found in any samples, limit of quantitation (LOQ) was estimated to be 0.008 mg/kg for the analytes except showing higher sensitivity of 0.002 mg/kg for chlorothalonil. GC/Mass spectrometric method using selected-ion monitoring technique was also provided to confirm the suspected residues. The proposed method was reproducible and sensitive enough to determine the residues of captan, folpet, captafol, and chlorothalonil in agricultural commodities for routine analysis.

• Korean Journal of Medicinal Crop Science
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• v.2 no.2
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• pp.168-173
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• 1994

Contents of essential oil and its composition in aerial part of Agastache rugosa were investigated. Essential oil was obtained from the dried stems, leaves and flowers by steam distillation and fractionated into hydrocarbon and oxygenated hydrocarbon by silica gel column chromatography. Each isolate or fraction was identified by GC and GC-MS. The contents of essential oil were 0.29% in leaves of Agastache rugosa on dry basis, 0.38% in flowers. Major components were ${\beta}-caryophyllene(59.3%)$, limonene(13.1%), ${\delta}-cadinene(10.7%)$ among 13 kinds of components confirmed in hydrocarbon fraction of essential oil isolated from leaves. Also, major components in oxygenated hydrocarbon fraction were methyl chavicol (79.1%) and cis-3(1-propenyl) phenol(4.5%) among 44 kinds components confirmed. The highest content among the components identified was methyl chavicol in both leaves and flowers. On the other hand, limonene, trans-2-hexenal, 1-octen-3-one, 6, 10, 14- trimethyl pentadecane- 2-one and phytol were detected typically in leaves, but jasmone and ${\rho}-methoxyacetophenone$ were detected mainly in flowers with small quantity.

• Applied Biological Chemistry
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• v.34 no.4
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• pp.312-317
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• 1991

The volatile components of Korean and Chinese Inulae flos were identified. It is made of dried Inulae flos from the components were collected by simultaneous steam distillation extract method. Those were analyzed by combined gas chromatography(GC) and gas chromatography-mass spectrometrt(GC/MS). Sixty two components, including 10 hydrocarbons, 7 aldehydes, 18 alcohols, 3 ketones, 5 esters, 13 acids and 6 miscellaneous components were identified. Volatile components in Inulae flos were fractinated into one hydrocarbon fraction and two oxygenated hydrocarbon fractions by using silica gel column chromatography. The volatile components consisted of 16.85% hydrocarbon and 83.15% oxygenated hydrocarbons in Korean Inulae flos, 23.46% hydrocarbon and 76.53% oxygenated hydrocarbons in Chinese Inulae flos.

• Korean Journal of Food Science and Technology
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• v.28 no.6
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• pp.1033-1037
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• 1996

An attempt was made to analyze preservatives in flavor-containing curry and tomato ketchup without interference due to their of flavor components. Samples were steam-distillated and extracted with ether. Sorbic acid, benzoic acid, dehydroacetic acid and salicylic acid were analyzed by GC with capillary column. Benzoic acid and dehydroacetic acid in curry were interfered by flavor components, but there was no interference in case of tomato ketchup. Samples were pretreated with Sep-Pak $C_{18}$ cartridge and analyzed with HPLC to avoid any interference due to flavor components. The recoveries by HPLC were higher than those by GC. Recoveries of sorbic acid, benzoic acid and salicylic acid from curry were 79.9%, 71.2% and 64.4%, respectively. Recoveries of sorbic acid, benzoic acid and salicylic acid from tomato ketchup were 83.4%, 87.8% and 77.7%, respectively.

• Korean Journal of Food Science and Technology
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• v.32 no.5
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• pp.997-1001
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• 2000

The organic acids in 3 kinds of medicinal herbal extracts were screened and compared each other according to their organic acid contents by an efficient gas chromatographic method. It involves solid-phase extraction of organic acids using Chromosorb P with subsequent conversion to stable tert-butyldimethysilyl derivatives for the direct analysis by capillary column gas chromatography and gas chromatography-mass spectrometry. Total of 24 organic acids were reproducibly identified from 3 kinds of herbal extracts. When the GC profiles were simplified to their retention index spectra, characteristic patterns were obtained for each herb sample. As expected, three kinds of herbal extracts showed three distinct patterns.