• Korean Journal of Microbiology
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• v.51 no.3
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• pp.249-255
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• 2015

A soil microorganism producing iron chelator (siderophore) under low iron stress (up to $2{\mu}M$ of iron) was identified as Acinetobacter sp. B-W by 16S rDNA sequence analysis, biochemical-, physiological tests and morphological analysis using electron microscope. Catechol nature of siderophore was detected by Arnow test. Although optimal cell growth was identified at $36^{\circ}C$ in iron-limited media, significant quantities of siderophore were produced only at $28^{\circ}C$. Biosynthesis of siderophore was strongly inhibited by growth at $36^{\circ}C$. Production of siderophore was completely inhibited by $10{\mu}M\;FeCl_3$. Iron chelator produced from Acinetobacter sp. B-W was purified from supernatant using butanol extraction, Sephadex LH-20 column chromatography and HPLC. Purified sideropore was identified as 2,3-dihydroxybenzoic acid by HPLC, TLC and IR analysis.

• Applied Biological Chemistry
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• v.50 no.4
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• pp.348-351
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• 2007

The stem barks of Fraxinus rhynchophylla was extracted with 95% EtOH, and the concentrated extract was successively partitioned with $CH_2Cl_2$, n-BuOH, and $H_2O$ in order to investigate the major phytochemicals. From the $CH_2Cl_2$ soluble fraction, a sterol (1) was isolated through the repeated silica gel column chromatographies. Three additional compounds (2-4) were isolated from the n-BuOH soluble fraction through silica gel, RP-18, and Sephadex LH-20 column chromatographies. Their chemical structures were elucidated as daucosterol $(1;{\beta}-sitosterol-3-O-{\beta}-D-glucopyranoside)$, caffeic acid (2), 6,8-dihydroxy-7-methoxycoumarin (3), and coniferaldehyde glucoside (4) by comparing their spectral data with those in the literatures. All isolates (1-4) were the first to be isolated from F. rhynchophylla.

• Applied Biological Chemistry
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• v.50 no.4
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• pp.344-347
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• 2007

The aerial parts of Lespedeza cuneata were collected, air-dried and extracted with 95% aqueous EtOH. Then it was successively partitioned with n-hexane, $CH_2Cl_2$, EtOAc and $H_2O$. Repeated Sephadex LH-20 column chromatography on the EtOAc- and $H_2O-soluble$ fractions gave four compounds. Their structures were elucidated as quercetin (1), kaempferol (2), desmodin (3) and homoadonivernith (4) on the basis of spectroscopic evidences such as $^{1}H-NMR$, $^{13}C-NMR$, 2D-NMR and MS spectrum. Desmodin (3) and homoadonivernith (4) have not been reported from this plant so far.

• Applied Biological Chemistry
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• v.50 no.4
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• pp.358-361
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• 2007

The heartwoods of Rhus verniciflua was extracted with $H_2O$ and the concentrated extract was partitioned with $CHCl_3$, EtOAc, n-BuOH and $H_2O$, successively. From the EtOAc and n-BuOH fractions, four compounds were isolated through the repeated silica gel, ODS and Sephadex LH-20 column chromatographies. They were determined as sinapyl aldehyde (1), 2,4-dihydroxybenzaldehyde (2), 2,4-dihydroxybenzoic acid (3) and 2,4-dihydroxyphenylglyoxylic acid (4) on the basis of spectroscopic data, respectively. Among the isolated compounds, sinapyl aldehyde $(34.7{\pm}0.6%)$ and 2,4-dihydroxyphenylglyoxylic acid $(43.8{\pm}0.9%)$ showed the strong antioxidative activity than artificial antioxidant BHT $(14.4{\pm}0.3%)$ in DPPH radical scavenging activity.

• Journal of the Korean Wood Science and Technology
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• v.34 no.6
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• pp.72-80
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• 2006

Fallen needle (8.5 kg) of Larix kaempferi were collected and extracted with 95% EtOH. The EtOH extracts were evaporated under reduced pressure, concentrated, and successively fractionated with a series of hexane, methylene chloride, ethylacetate and water on a separatory funnel to be freeze dried. A portion of ethylacetate and water soluble powder were chromatographed on a Sephadex LH-20 column eluting with aqueous MeOH and EtOH-hexane mixture. Spectrometric analyses such as NMR and FAB-MS, including TLC, were performed on the seven isolated compounds and were elucidated as (+)-catechin, (-)-epicatechin, 2"-O-rhamnosylvitexin, juglanin, afzelin, laricitrin-3-O-${\beta}$-D-glucopyranoside, isoquercitrin and cedrusin.

• Food Science and Preservation
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• v.15 no.6
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• pp.878-883
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• 2008

Prunus mume was extracted using various solvents including ethyl ether, ethyl acetate and n-butanol. The extracts were fractionated by column chromatography. Antimicrobial compounds (A, B and C) in fractions showing antimicrobial activity were purified by Sephadex LH 20 column chromatography, and identified by $^{1}H$- and $^{13}C$-NMR analysis as isoeugenol, nomilin and $\beta$-sitosterol, respectively.

• Journal of the Korean Wood Science and Technology
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• v.41 no.4
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• pp.269-275
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• 2013

Antifungal and insecticidal activity of Korean traditional medicinal plants was carried out to develop natural material for the development of organic cultural heritage conservation. As a result, Phellodendron amurense fruit was finally selected as a candidate of antifungal and insecticidal natural material. An novel active compound was purified from the ethylacetate fraction of Phellodendron amurense fruits using silica gel and Sephadex LH-20 column chromatography and PTLC. The compound was obtained as yellow oil form; UV ${\lambda}_{max}$(MeOH): 260 nm. The chemical structure of novel compound was determined as (4'-ethyl-2'-methylfuranyl)-6-methoxy-7-methylnona-2E,4E,6Z,8E-tetraenoic acid on the basis of various NMR experiments including $^1H$- and $^{13}C$-NMR, HMQC, HMBC and ESI-mass spectrum.

• Applied Biological Chemistry
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• v.36 no.2
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• pp.99-104
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• 1993

In order to explore the brassinosteroid-active component in Cassia tora, methanol extract of immature seeds was purified by sequences of solvent fractionation, silica gel adsorption chromatography, Sephadex LH-20 chromatography, charcoal adsorption chromatography and Bondesil chromatography. The activity of brassinosteroid was monitored by the rice inclination test and its presence could be confirmed in each purification step. The purified active components were separated by silica gel adsorption chromatography. Brassinosteroid substances in separated active fractions were identified as teasterone, castasterone, brassinolide by TLC and HPLC. Our work is probably the first report of endogenous brassinosteroid in Cassia tora. The content of brassinosteroid in Cassia tora as converted into brassinolide was $3.5{\sim}5.5\;ng/g$ fresh weight. The order of brassinosteroid contents was toward to be teasterone, castasterone, brassinolide.

• Applied Biological Chemistry
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• v.42 no.3
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• pp.262-266
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• 1999

Thirty plants were screened for their antioxidative activity. The extracts of Agastache rugosa, Schizonepeta tenuifolia and Lycopus lucidus had high free radical(2,2-diphenyl-1-picrylhydrazyl) scavenging activities. Methanol extract of Agastache rugosa was fractionated with hexane, chloroform, ethyl acetate, and water. The ethyl acetate fraction showed the highest antioxidant activity in the DPPH test. The ethyl acetate fraction was applied to Sephadex LH-20 column, and the fractions showing antioxidative activity were collected and used for identification of the substance. The purified substance was applied to mass, IR, UV and NMR spectroscopy. The spectra of mass, IR, UV and NMR implied that the substance is a rosmarinic acids as a kind of phenolic compound. The rosmarinic acid has more antioxidative effect than those of BHT and ${\alpha}-tocopherol$ in the Rancimat test.

• Applied Biological Chemistry
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• v.43 no.4
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• pp.298-302
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• 2000

In our investigation on chemical constituents of edible mushrooms, seven compounds I-VII have been isolated from the methanolic extract of the fruit body of Sarcodon aspratus. The methanolic extract was separated by solvent partition, silica gel column chromatography and Sephadex LH-20 column chromatography, and compounds I-VII were finally purified by preparative HPLC or TLC. Their structures were assigned as 4-hydroxybenzoic acid methyl ester, 4-hydroxybenzaldehyde, cyclo(Ala-Pro), adenosine, nicotinamide, BL V, linoleic acid, respectively, on the basis of mainly $^1H\;NMR$ spectra.