• Korean journal of applied entomology
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• v.25 no.4 s.69
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• pp.229-233
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• 1986

By using the test fungus Macrophomina phaseolina, residues of triadimefon were found in straw collected after harvest from sprayed plants of wheat varieties Kharchia and Lal Bahadur but grains contain no such residues. Thin layer chromatographic method was developed to detect residues of the fungicide which was found to be present in straw of sprayed plants of both the varieties. No residues could be detected in grain samples. It was found that triadimefon was converted in triadimenol in/to host.

• The Research Journal of the Costume Culture
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• v.12 no.4
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• pp.579-590
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• 2004

This research was aimed to investigate and compare the effectiveness of TLC and GC-MS methods in the analysis of chromophoric substances extracted from madder plant. Alizarin and purpurin 0.3% solution were used as comparative standards; madder extraction was prepared by heating the solution of powdered madder at 80℃, pH 1.5, for 90 min. Best elution solvent for TLC in silica gel plate was toluene:ethyl acetate=9:1, which resulted in red and yellow spots from madder extraction each of which showed R/sub f/ values 0.32-0.43 and 0.07-0.11. Although the red spot in particular exhibited similar characteristics as standard purpurin in color, shape, and R/sub f/ values, the result was inconsistent throughout different TLC trials. GC-MS analysis showed only small amount of alizarin and no purpurin in the madder extraction. Other chromophoric substance such as 2-furancarboxaldehyde, 5-(hydroxymethyl)-, anthralin, and danthron were also detected in small amounts. The result indicated that TLC was less sensitive to detecting and identifying the natural dyestuff which is generally constituted with a number of similar but chemically different chromophoric substances.

• Journal of Life Science
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• v.16 no.2 s.75
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• pp.328-332
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• 2006

The possible presence of inhibitors of pancreatic lipase (tricaylglycerol acylhydrolase EC 3.1.1.3) was screened from Korean traditional edible or medicinal herbs. Among tested herbs, Arecae pericarpium, Mucunae Caulis, Rhus javanica, Thujae orientalis were shown to have strong inhibitory effect against pancreatic lipase. Thujae orientalis was finally selected as a candidate for pancreatic lipase inhibitor. The extract of Thujae orientalis was showed selective inhibition on porcine pancreatic lipase activity. Active inhibitors, TF-1, TF-2, TF-3, were purified from an extract of Thujae orientalis, using chloroform extraction, followed by successive chromatography in silica gel and LH-20 and high performance liquid chromatography (HPLC). The $IC_{50}$ values of TF-1, TF-2, TF-3 and orlistat were 44.7, 98.7, 46.1 and $27.6{\mu}g/ml$, respectively. And also the TF-2 and orlistat were shown to be inhibitory effect on the differentiation of preadipocyte NIH-3T3 L1 cells at a concentration of $10{\mu}g/ml$.

• Applied Biological Chemistry
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• v.34 no.2
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• pp.149-153
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• 1991

Several commercial soybean oils were stored at $20^{\circ}C,\;40^{\circ}C$ and $60^{\circ}C$ with daily exposure of fluorescent light for 12 hours and evaluated their rancidity by headspace gas chromatographic analysis of pentanal and hexanal. The data of gas chromatographic analysis was compared with organoleptic flavor evaluation. For headspace gas chromatographic analysis, the volatile compounds were recovered by porous polymer trap and flushed into a fused silica capillary column at $250^{\circ}C$, The pentanal and hexanal separated were identified by gas chromatography and gas chromatography-mass spectrometric method. The results showed that the contents of pentanal and hexanal were linearly increased during storage for 100 days. A very simple linear relationship was found between organoleptic flavor scores and amounts of two volatile compounds with very high correlation coefficient. A similar linear relationship was also obtained for acid and peroxide value with sensory data. This results suggested the possible implication of pentanal and hexanal as an quality index for rancidity evaluation of soybean oil.

• YAKHAK HOEJI
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• v.39 no.4
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• pp.427-432
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• 1995

The plasma oscillation has been observed in an argon pressure between a tungsten anode and cathode consisting of an aqueous conducting solution. The effects of experimental parameters on the electrical characteristics of the glow discharge have been studied. The experimental parameters include the anode-cathode distance, pressure, methanol flow rate, and cathode materials. The glow discharge with liquid cathode and solid anode showed the potential sensitive detector for HPLC

• Journal of Oral Medicine and Pain
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• v.25 no.1
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• pp.9-28
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• 2000

The purpose of this article, the first part of series, is to describe the general theory applicable to various chromatographic procedures. History of chromatography, separation of matters, classification of chromatography, underlying principles of separation in chromatography, covering resolution, column efficiency, column selectivity, and capacity factor, movement of solute in chromatographic phase, including elution development, displacement development, and frontal analysis, were discussed. Mathematical description of plate theory and thermodynamic viewpoint of retention were emphasized.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1994.04a
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• pp.275-275
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• 1994

생체시료 중 극미량성분분석에 관한 필요성이 높아지고 있으며 기존의 분석기기를 사용하여 분석방법을 개발하는 연구나 새로운 분석기기를 개발하는 연구들을 통하여 이들 물질들을 분석하고자 하고있다. 특히 극미량성분인 경우 생체내에 수십 Pg이 존재하면서 이들의 농도변화가 생리활성에 변화를 주기 때문에 검출한계가 낮은 검출기가 필요하게되며 또한 생체시료중의 여러물질들로 인하여 이들을 분리하는 크로마토그라피기술과 이들이 분리된 후 실제로 어떠한 물질인지를 확인할 수 있는 즉 정성까지 가능한 검출기의 개발이 요구되고 있다.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1996.04a
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• pp.164-164
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• 1996

생약(5kg)을 분말로 한 뒤, MeOH 4$\ell$로 24시간, 2회, 환류추출, 추출액을 감압 농축하여 MeOH ex. (450g)을 얻었다. 이것을 물에 현탁시켜 헥산, 벤젠, 에틸아세테이트, 수층으로 분획, L1210 세포에 대하여 이들 분획물과 vincristine의 병용효과를 관찰하였다. 그 결과, 벤젠분획물에서 강한 효과가 있었으므로 컬럼크로마토그라피하여 물질을 분리하였다.

• YAKHAK HOEJI
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• v.16 no.1
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• pp.55-64
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• 1972

The determination method of l-ephedrine and dl-methylephedrine by gas chromatography was developed, using reactive alkaline precolumn packed with celite 545 containing KOH. Symmetrical peaks were achieved under the condition, inlet temperature, $180^{\circ}C$-$230^{\circ}C$; column temperature, $180^{\circ}C$- $160^{\circ}C$; carrier gas flow rate, 30ml/minute. The peaks of the salts coincided with those of bases. When this method was applied to preparations, using d-dimethylaminobenzaldehyde as inner standard, good results were obtained. The relative retention times of l-ephedrine and dl-methylephedrine to p-dimethyl aminobenzaldehyde were 0.50 and 0.65 respectively.

• Journal of Industrial Technology
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• v.19
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• pp.409-413
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• 1999

Chemical oxidation of humic acid by ozonation process was investigated in the batch reactor. Aldehydes and ketone were identified as PFBOA derivatives in ozonated humic acid solutions using gas chromatography with PDECD. The formaldehyde was as a main by-product of ozonation. The characteristics of the formaldehyde production were discussed with respect to concentration at different experimental conditions.