• Applied Biological Chemistry
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• v.37 no.5
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• pp.392-396
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• 1994

The toxic substance causing blown blotching on the mushroom cap was extracted and purified from the culture broth of P.tolaasii. Purification and identification of the toxic compound was carried out with the silica gel chromatography, mass spectrum and NMR and appeared to be an aminobenzene in amylamine group. The purified toxic substance showed UV spectrum at 234nm and melting point at $76^{\circ}C$, respectively.

• Journal of the Korean Chemical Society
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• v.39 no.7
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• pp.524-529
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• 1995

The separation efficiency of metal ions by using silica gel bonded 15-crown-5 (SGBM) has been determined by column chromatography in aqueous solution at pH 1. Bindinng constants and separation factors for several SGBM-Metal interactions were measured in aqueous solution. The order of these binding constants and separation factors with metal ions was Li(Ⅰ) < Sr(Ⅱ) < Na(Ⅰ) < Cu(Ⅱ) < Mg(Ⅱ) < K(Ⅰ) < Ca(Ⅱ) < Bi(Ⅲ) < Sb(Ⅲ). These results were explained in terms of the size effect and electron density effect. This experimental results showed good efficiency for separation of $Sb^{3+}$ from mixtures of alkali, alkaline earth metal ions, and $Cu^{2+}$ in aqueous solution.

• Journal of Applied Biological Chemistry
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• v.63 no.4
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• pp.319-325
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• 2020

The liquids of Lycopersicon esculentum were extracted with 70% aqueous MeOH and the concentrates were partitioned into EtOAc, n-BuOH, and H2O fractions. The repeated silica gel and octadecyl silica gel column chromatographies for the EtOAc fraction, whose activity was confirmed, led to isolation of one flavonol compound. The chemical structures of the compound were determined as quercetin (1) based on spectroscopic analyses including nuclear magnetic resornance, infrarad spectroscopy, and mass spectroscopy. Through this study, the antioxidant efficacy was confirmed by demonstrating that the L. esculentum fraction showing an increase in glutathione mean (GM) and a decrease in glutathione heterogeneity (GH) uniformly raises the intracellular glutathione (GSH) level.

• The Korean Journal of Pesticide Science
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• v.14 no.4
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• pp.361-370
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• 2010

Considering the efficiencies of the preparation process at each stage obtained in previous studies, the analytical determination method was established for multi-pesticide residues in soils. It consist of the acetone-extraction, the dichloromethane-partition, the Florisil or silica-gel chromatography and the gas chromatography analysis equipped with the electron capture detector and the nitrogen-phosphorus detector. In the soil recovery test by Florisil clean-up system, the number of pesticides recovered in the range of 70~120% and showed less than 20% of RSD were 165 pesticides for paddy soil, 169 pesticides for upland soil and 159 pesticides in both soils through the tested 183 pesticides. And in the soil recovery test by silica-gel system, the number of pesticides recovered in the range of 70~120% and showed less than 20% of RSD were 154 pesticides for paddy soil, 145 pesticides for upland soil, and 134 pesticides in both soils.

• KSBB Journal
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• v.6 no.2
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• pp.123-128
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• 1991

The production of bassinosteroid-like substances of two hybrid types of Korean rice, Jangseongbyeo, Taebackbyeo were investigated. The shoots at the maximum tillering stage were extracted and purified by solvent fractionation, silica gel adsorption chromatography Sephadex LH-20 chromatography, charcoal adsorption chromatography, Bondesil chromatography and HPLC of reverse phase, successively. Biological activities of each purification step were monitored by the rice lamina inclination test. Higher activities against the rice lamina inclination test in the each purification step showed that the shoots of two cultivars biosynthesize brassinosteroids. Two cultivars also showed a similar distribution of biological activities of endogenous brassinosteroids detected by HPLC.

• YAKHAK HOEJI
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• v.25 no.4
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• pp.137-143
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• 1981

In order to confirm the exact antipyretic component in the earthworm, etherial extract of American earthworm(Red Worm) was fractionated into five fractions by using silica gel column chromatography and thin layer chromatography. The fraction including free fatty acids was found to possess artipyretic response and standard arachidonic acid showed marked antipyretic response on typhoid vaccinated rabbits. Arachidonic acid was identified from the free fatty acid fraction of the earthworm by using gas liquid chromatography. Thus it was considered that the antipyretic activity of the free fatty acid may be due to the presence of arachidonic acid. Lipid-free earthworm powder was extracted with phosphate buffer (pH, 8.0, 0.1M) and all the proteins was salted out by ammonium sulfate. The crude precipitate was dialyzed and the impure proteins were eliminated at pH 5.4 and 4.6. The remaining protein solution was fractionated with various concentrations of acetone. The acetone fractions were identified by using S.D.S. polyacrylamide gel electrophoresis and disc gel electrophoresis. The precipitate at 85% acetone concentration and the remaining proteins in the supernatant did not exhibit the antipyretic activity.

• The Korean Journal of Pesticide Science
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• v.14 no.4
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• pp.347-360
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• 2010

In order to develop the multi-residue purification method for 180 pesticides commonly used in Korea, many analytical methods on individual and multi- pesticide residues in the agricultural commodities and food product were examined. Through the modification of adsorption chromatographic methods used in Europe, the United States and Korea, the Florisil and silica-gel chromatographic systems were developed. Through these purification systems, elution profiles for all pesticides were examined. As the results, 145 pesticides were recovered in the range of 70-120% in Florisil clean-up system. The distribution of pesticides in the elution profile was 12 pesticides in the first fraction, 76 pesticides in the second fraction, 81 pesticides in the third fraction, 60 pesticides in the fourth fraction and 30 pesticides in the last fraction. And, in silica-gel system, 137 pesticides were recovered in the range of 70~120%. The distribution of pesticides in the elution profile was 22 pesticides in the first fraction, 59 pesticides in the second fraction, 102 pesticides in the third fraction, 46 pesticides in the fourth fraction and 8 pesticides in the last fraction.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.7
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• pp.1059-1065
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• 2003

Antimicrobial activity of Mokdan bark (Paeonia suffruticosa $A_{NDR}$) was investigated. Methanol extract of dried Mokdan was fractionated to hexane, chloroform, ethylacetate, butanol and aqueous fraction. Ethylacetate fraction among these fractions showed the highest inhibitory effect on the microorganisms such as L. monocytogenes, and E. coli at 500 $\mu\textrm{g}$/disc. Ethylacetate fraction was further fractionated into 3 fractions by silica gel column and thin layer chromatography (TLC). The results showed that ethylacetate fractions No. 1 and 2 had the highest antimicrobial activity. They were mixed again, reseparated, and 3 fractions were obtained. Among them, No. 1 had the highest inhibitory effect on the microorganisms, No. 1 fraction was identified as isobutyl isopentanoate by HPLC, and GC-MS.

• Journal of the Korean Applied Science and Technology
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• v.33 no.2
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• pp.255-263
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• 2016

Antimicrobial properties of Licorice(Glycyrrhizae radix L.) against food spoilage microorganism, Bacillus subtilis KCTC 1021 was investigated. Antibacterial activity of the essential oil was as equivalent as Potassium metabisulfite and myconazole. The licorice extracts was fractionated to hexane, chloroform, ethyl acetate, butanol and water fraction. Chloroform fraction showed the highest inhibitory effect on the Bacillus subtilis KCTC 1021. Chloroform fraction was further fractionated by silica gel column chromatography and thin layer chromatography(TLC). The antibacterial compound was isolated from their fractions and its chemical structures was identified as (R)-glabridin by ESI-MS, $^1H$-NMR and $^{13}C$-NMR.

• Korean Journal of Food Science and Technology
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• v.36 no.4
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• pp.643-647
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• 2004

Natural antimicrobial substance from peanut (Arachis hypogaea) shells was isolated and structurally elucidated. Peanut shells were extracted with methanol (MeOH) and concentrated in vacuo, MeOH extract was solvent-fractionated with ethyl acetate (EtOAc) and various buffer to obtain EtOAc acidic, neutral, and phenolic fractions. EtOAc neutral fraction, which showed antimicrobial activity, was purified through silica gel adsorption column, Sephadex LH-20 column, ODS column, and high performance liquid chromatographies, and its active substance was isolated and identified as pratensein (3',5,7-trihydroxy-4'-methoxyisoflavone) by spectroscopic methods of proton-nuclear magnetic resonance, mass spectrometry, and nuclear overhauser enhancement spectroscopy.