• Microbiology and Biotechnology Letters
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• v.30 no.1
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• pp.21-25
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• 2002

Structural analysis was performed by the $^1$H-NMR, $^{13}$ C-NMR, amino acid composition analysis and FAB-mass. The instrumental analysis represented that the potential antifungal antibiotic belonged to the iturin E group antibiotic, consisting of 7 $\alpha$-amino acid residues and a collection of $\beta$-amino acid with aliphatic side chain. Compared to the Iturin E group, notably, the potent antifungal antibiotic from Bacillus sp. YJ-63 carried longer $\beta$-amino acid side chain. In conclusion, these findings identified a potential antibiotic, which contained a stable cyclopeptide structure with long $\beta$-amino acid side chain.

• Journal of the Korean Chemical Society
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• v.54 no.1
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• pp.49-54
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• 2010

A new series of novel 2-morpholino-N-(4,6-diarylpyrimidin-2-yl)acetamides 34-42 is synthesized by the condensation of 2-chloro-N-(4,6-diarylpyrimidin-2-yl)acetamides 25-33 with morpholine in the presence of anhydrous potassium carbonate. The synthesized compounds have been characterized by melting point, elemental analysis, MS, FT-IR, one-dimensional NMR ($^1H$ & $^{13}C$) spectroscopic data.

• The Korean Journal of Food And Nutrition
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• v.24 no.4
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• pp.617-621
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• 2011

$Coptis$ $chinensis$ Franch rhizome is one of the important traditional Korea medicines with anti-inflammatory, anti-bacterial, anti-hypertensive and anti-cancer properties. The methanol extract of rhizome from the $Coptis$ $chinensis$ rhizome was purified by using preparative centrifugal partition chromatography (CPC) and HPLC method. The optimum two-phase CPC solvent system was composed of n-butanol:acetic acid:water at a ratio of 4:1:5. Berberine (16.8 mg) was successfully isolated by CPC and HPLC. The chemical structure of the compound was identified by (1 H)$^1H$, $^{13}C$-NMR and ESI-MS spectral data analysis.

• Microbiology and Biotechnology Letters
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• v.21 no.1
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• pp.36-40
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• 1993

A bacterial strain, producing extracellular inulin fructotransferase which converts inulin into di-D-fructofuranose dianhydride (DFA) was isolated from soil and presumed as Enterobacter sp. The DFA isolated on Bio-gel P2 column was identified as DFA III by high performance liquid chromatography and $^13C-nmr$ spectroscopy. The enzyme production was induced by inulin and markedly enhanced by the addition of corn steep liquor and $NH_4H_2P0_4$ for nitrogen source. Under optimum condition, the enzyme activity in the culture broth reached at maximum, 0.22 unit/ml after cultivation for 72 hour.

• Journal of the Korean Chemical Society
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• v.41 no.3
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• pp.157-165
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• 1997

The transesterification reaction could be used to the technical production as it forms an in-situ compatibilizer during the processing of polymer blends. Thus, TR-4,6(poly(tetramethylene-4,4'-terephthaloyldioxydibenzoate-co-hexametylene-4,4'-terephthaloyldioxydibenzoate), one of thermotropic liquid crystalline polymers was synthesized and was blended with PBT(polybutylene terephthalate), one of engineering plastics, to study the transesterification reaction. The transesterification reactions between two components, TR-4,6 and PBT, were monitored by IR, DSC and $^{13}C-NMR$ and analyzed by a statistical treatment method. Also, the reaction rates and the sequence distributions of repeating unit were (calculated and) invesitigated.

• Journal of the Korean Wood Science and Technology
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• v.29 no.4
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• pp.53-59
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• 2001

The needles of torreya(Torreya nucifera S. et Z) were collected, extracted with acetone-$H_2O$(7:3, v/v), fractionated with hexane, chloroform and ethylacetate, and freeze dried to give some dark brown powder. The ethylacetate soluble mixture was chromatographed on a Sephadex LH-20 column using a series of aqueous methanol and ethanol-hexane mixture as eluents. Most of the needle extractives were flavan and its methyl ether compounds such as (+)-catechin, (-)-epicatechin, (+)-gallocatechin, (-)-epigallocatechin, 3'-O-methyl-(+)-catechin and 3'-O-methyl-(-)-epicatechin including protocatechuic acid, one of benzoic acids. $^1H$- and $^{13}C$-NMR, NOE and CI-MS analyses were performed to elucidate the structures of the isolated compounds.

• Korean Journal of Microbiology
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• v.54 no.2
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• pp.136-139
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• 2018

The inhibitory compound (Compound S) against Ralstonia solanacearum and its conversion product (Compound S') were isolated from the culture filtrate of Bacillus subtilis JW-1 using a series of chromatography procedures. The structures were elucidated as alanyl-L-${\beta}$-(2,3-epoxycyclohexyl-4-one)alanine and alanyl-L-${\beta}$-(2,3-dihydroxycyclohexyl-4-one)alanine, respectively on the basis of nuclear magnetic resonance spectral data, including $^1H$, $^{13}C$, $^1H-^1H$ correlation spectroscopy and heteronuclear multiple bond correlation spectroscopy. The compound S exhibited a broad antimicrobial activity against $G^+$, $G^-$ bacteria, Saccharomyces cerevisiae and Candida albicans. The activity loss of the conversion product revealed that the epoxy function was essential for activity of Compound S.

• The Korean Journal of Food And Nutrition
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• v.11 no.3
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• pp.347-353
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• 1998

An antibiotic for methicillin resistant Staphylococcus aureus(MRSA) produced by Streptomyces lydicus YSK-681 was extracted by chloroform, and then purified by the C18 reversed-phase HPLC and silica gel column HPLC. The molecular weight of the purified antibiotic was determined from the FAB analysis MS an m/z 1022.4 and 1036.4(M+H)+, indicating that the isolated antibiotic consisted of two similar compounds with the molecular weight difference of 14 m/z value. With the aid of the various nuclear magnetic resonance(NMR) spectroscopic techniques such as 1H NMR, 13C NMR, DEPT and HMQC spectroscopy, the characteristics of function al groups were deduced as the hydroxyl group and leucine. The MIC values of the purified antibiotic were observed at 1∼32 $\mu\textrm{g}$/$m\ell$ against Gram-positive bacteria compared to > 125 $\mu\textrm{g}$/$m\ell$ against Gram-negative bacteria or fungi. The antibiotic was active at 8 $\mu\textrm{g}$/$m\ell$ of MIC90 and S180 at the concentration of 500 $\mu\textrm{g}$/$m\ell$.

• Applied Chemistry for Engineering
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• v.23 no.3
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• pp.284-288
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• 2012

This work deals with the chemical characterization of glycine aqueous solution in $CO_2$ absorption. Three alkali elements were impregnated into the glycine in order to facilitate the formation of amino functionalities. The analysis by IR revealed the transformation of ammonium ions to the amino group. In addition, the NMR analysis showed that the substitution of metal cations to the chemical shift of hydrogen and carbon atoms in glycine; in order of lithium glycinate, sodium glycinate and potassium glycinate depending on the electro negativity. Meanwhile, the $CO_2$ absorption at room temperature was the highest in primary amine solution, but at the increasing temperature sodium glycinate could capture more $CO_2$ than that of the pure amine solution.

• The Korean Journal of Pesticide Science
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• v.3 no.1
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• pp.13-19
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• 1999

Insecticidal potentials of polar and non-polar tractions obtained from 84 medicinal plants were screened against five major agricultural insects. Based on the primary and secondary screening results, non-polar fraction of Atractylodes koreana Kitam. rhizomes was selected to isolate and identify an active compound effective to diamondback moth (Plutella xylostella L.) larvae. Counter-current distribution separation on the non-polar fraction and TLC and spectroscopic analyses (GC-MS and $^{1}H$- and $^{13}C$-NMR) revealed that molecular formula of the active compound was $C_{15}H_{22}O$ known as a sesquiterpenoid 4,11-selinadien-3-one (${\alpha}$-cyperone). However, ${\alpha}$-cyperone was not detected in the non-polar fractions that showed high insecticidal potential against the diamondback moth. Although ${\alpha}$-cyperone has been first identified from Cyperus rotundus, the compound did not occur in C. rotundus cultivated in Korea.