• Microbiology and Biotechnology Letters
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• v.25 no.6
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• pp.586-591
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• 1997

In the course of screening for the tipA promoter-inducing substances, we isolated an active compound, sulfomycin Ia, from the mycelium of a microorganism designated 50634. The producing organism was identified as Streptomyces sp. on the basis of taxonomic studies. Sulfomycin Ia was purified from mycelial extract by silica gel column chromatography, LH-20 column chromatography, silica gel TLC, and preparative HPLC. The molecular weight of sulfomycin Ia was determined to be m/z 1129 (M+Na)$^{+}$ by FAB mass measurement and $^{1}$H NMR spectroscopic analysis. The structure was assigned as a derivative of sulfomycin I with thiazole, methyloxazole, oxazole, and pyridine rings by $^{1}$H NMR spectral data.

• Microbiology and Biotechnology Letters
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• v.23 no.1
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• pp.98-103
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• 1995

During the screening of antifungal antibiotics from microbial metabolites, we selected Pseudomonas aeruginosa KGM-100 showing powerful antagonistic activity against various phytopathogenic fungi. Antibiotics KGM-100A and KGM-100B were purified from the culture broth of Pseudomonas aeruginosa KGM-100 by diaion HP-20 column chromatography, ethyl acetate extraction, silica gel column chromatography, preparative TLC and recrystallization. KGM-100A which was recrystallized in MeOH showed antimicrobial activities against a broad spectrum of fungi and bacteria. Physico-chemical properties of KGM-100A were determined and identified to be phenazine-l-carboxylic acid by UV, IR, $^{1}$H-NMR, $^{13}$C-NMR, mass spectrum, and elemental analyses.

• Mass Spectrometry Letters
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• v.6 no.4
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• pp.99-104
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• 2015

A liquid chromatography mass spectrometry (LC-MS) system was used to identify and distinguish oligostilbene diastereoisomers. A polyphenolic extract from Neobalanocarpus heimii known to be rich in oligostilbenes of various degrees of condensation was used as test material. Fourteen oligostilbenes were isolated from this extract on a fully automated semi-preparative HPLC system. Out of these, two pairs of dimers, one pair of trimers, two pairs of tetramers and a group of four tetramers with similar skeleton were identified as diastereoisomers. Their structures and configurations were established by spectroscopic methods. All isolated compounds were subjected to an LC-MS/MS to study their fragmentation patterns. The experiments were performed on a liquid chromatography-mass spectrometry (LC-MS) with electrospray-ionization (ESI) interface in positive mode. MS/MS spectra of each pure compound were recorded by direct infusion in identical conditions and their product ion spectra were analysed. Some subtle yet significant differences were observed between the spectra of oligostilbenes from the various diastereoisomeric series.

• Microbiology and Biotechnology Letters
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• v.16 no.3
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• pp.219-225
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• 1988

Two isozymes of cellobiohydrolase and fifteen isozymes of endoglucanase from Trichodema viride QM 9414 were purified by ammonium sulfate fractionation, Sephadex G-100 column chromatography, DEAE-Sephadex A-50 column chromatography and preparative electrophoresis. The purified cellobiohydrolnse had a molecular weight of 71,000 estimated by electrophoresis and amino acid analysis showed its main amino acids to be in the form of aspartic acid and glutamic acid result-ing from its low pI point of 3.81. The optimum pH and temperature were 5.1 and 5$0^{\circ}C$ respectively.

• Journal of Microbiology and Biotechnology
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• v.22 no.9
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• pp.1214-1217
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• 2012

One Helicosporium strain, isolated from a wilted chestnut tree, evidenced in vitro antimicrobial activity against various types of bacteria and fungi, and generated a diffusible pigment. The antimicrobial compounds and the diffusible pigment of the Helicosporium sp. isolate were purified via solvent fractionation, column chromatography, and recycling preparative chromatography. Both the major antimicrobial compound and the diffusible pigment were identified as 2-methylresorcinol via nuclear magnetic resonance spectroscopy. Therefore, 2-methylresorcinol, a diffusible pigment generated by Helicosporium sp., appears to be an active antimicrobial principle. This pigment also exhibited considerable cytotoxicity against mammalian cells.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.04a
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• pp.110.2-111
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• 2003

삼백초 지상부를 탈지후 60% acetone으로 추출하고 이를 극성에 따라 diethyl ether, ethyl acetate, aqueous fraction과 같이 용매분획하였다. 각 fraction의 superoxide anion, hydrogen peroxide, hydroxyl radical, DPPH radical 에 대한 소거활성을 측정하였다. Diethyl ether fraction의 ROS 소거효과가 비교적 강하였으며 superoxide anion 소거활성은 100ppm에서 86.88%였고, hydroxyl radical 소거활성은 1ppm에서 85.3%로 나타났다. Hydrogen peroxide, DPPH radical 소거활성은 ethyl acetate fraction이 강하게 나타났다. Diethyl ether fraction으로부터 silica gel column chromatography, sephadex LH-20 column chromatography, preparative HPLC에 의하여 수 종의 성분을 분리하였으며 현재 구조동정과 이들의 LDL산화억제 효과 시험 중에 있다.

• Mycobiology
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• v.37 no.1
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• pp.31-36
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• 2009

A phytochemical study on the flower of Calotropis gigantea (Linn.) using silica gel column chromatography and preparative thin layer chromatography, led to the first time isolation of Di-(2-ethylhexyl) phthalate (compound 1) and anhydrosophoradiol-3-acetate (compound 2). The structures of these compounds were confirmed by spectroscopic analyses (IR, HRTOFMS and NMR). The antibacterial and antifungal activities of ethyl acetate extract, compound 1 and compound 2 were measured using the disc diffusion method. Ethyl acetate extract and compound 1 presented better results than compound 2. The minimum inhibitory concentrations (MICs) of the extract and compounds were found to be in the range of $16{\sim}128{\mu}g/ml$. The cytotoxicity ($LC_{50}$) against brine shrimp nauplii (Artemia salina) were also evaluated and found to be 14.61 ${\mu}g/ml$ for ethyl acetate, 9.19 ${\mu}g/ml$ for compound 1 and 15.55 ${\mu}g/ml$ for compound 2.

• Journal of Food Hygiene and Safety
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• v.12 no.3
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• pp.195-199
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• 1997

For the purpose of isolation and screening of tyrosinase inhibitory activity from edible mushrooms, Pleurotus ostreatus, Auricularia auricula-Judae, Umbilicaria esculenta, Agaricus bisporus, Flammuline velutipes, Lentinus edodes, Ganoderma lucidum, and Coriouls versicolor were examined by tracing inhibitory activities against tyrosinase, utilizing L-3,4-dihydroxyphenylalanine (L-DOPA) as a substrate. Among the eight edible mushrooms tested, Umbilicaria esculenta showed potent enzyme inhibitory activities above 7804% against tyrosinase in ethylacetate (EtOAc) extracts. Ganoderma lucidum and Agaricus bisporus showed inhibitory activities of 67.3% and 51.5% in water extracts. EtOAc extracts of Umbilicaria esculenta was fractionated from silicagel column chromatography and one fraction showed the most inhibitory activity of 60.9%. The three bands (Rf=0.38, 0.27, 0.19) were isolated from preparative TLC of the fraction for purification and identified as mixtures of orsellinate, methyl orsellinate, methyl lecanorate, and methyl gyrophorate by high pressure liquid chromatography (HPLC), ultravisible spectrophotometer (UV), mass spectrophotometer (Mass), nuclear magnetic resonance spectrometer (NMR).

• Proceedings of the Korean Society of Applied Pharmacology
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• 1998.11a
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• pp.130-130
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• 1998

Two novel compounds SSC1 and SSC2 were isolated from culture broth produced from the strain of Stereum hirsutum by using of YM broth. They were isolated through HP-20 column chromatography, silica gel column chromatography and preparative HPLC, successively. The molecular formulas of SSC1 and SSC2. were determined as C$\sub$15/H$\sub$22/O$_3$ by high resolution EI -mass. The chemical structures of SSC1 and SSC2 were determined as sesquiterpenoid compounds by spectroscopic analysis of UV, IR, $^1$H NMR, $\^$13/C NMR, DEPT, HMQC and HMBC spectrum.

• Microbiology and Biotechnology Letters
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• v.23 no.4
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• pp.411-415
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• 1995

The dextranase (EC 3.2.1.11) produced by Aspergillus ustus GR-98 was purified by the following sequential methods; salting-out and dialysis, gel filtration on BIO-GEL P-100, ion exchange chromatography on DEAH-cellulose, affinity chromatography on hydroxyapatite, and preparative electrophoresis. Three active fractions, dextranases 1, 11 and 111, were isolated in electrophoretically pure states, and specific activities of the dextranases were 1,276, 1,154 and 1,125 units/mg, the degrees of yield were 9.0, 3.6 and 2.2%, having 145, 131.1 and 127.8 times as those of culture filtrate in degree of purification, respectively. The enzyme purity was confirmed by the PAGE, SDS-PAGE and get permeation-HPLC.