• 한국식물병리학회지
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• 제12권3호
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• pp.302-306
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• 1996

항균물질을 생산하는 방선균 KGT-37를 인삼밭 토양에서 분리하여 배양액으로부터 항균물질을 분리하고 silica gel column chromatography, preparative TLC, HPLC로 정제하였다. \ulcornerH-\ulcornerH COSY, HMQC, HMBC등 NMR 분석결과 KGT-37이 생산하는 항균물질은 cyclic depsipeptide계의 항생물질인 echinomycin으로 동정되었으며 이 연구에서 지금까지 assign되지 않았던 \ulcornerH과\ulcornerC의 NMR signal이 완전히 assign되었다. 이 항균활성물질은 감자더뎅이병균인 Streptomyces scabies과 Corynebacterium lilium을 포함하는 그람 양성 세균에 특히 강한 항균활성을 보였으며, 도열병균 및 점무늬낙엽병균 등 병원곰팡이에도 항균활성을 나타내었다.

• Journal of the Korean Wood Science and Technology
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• 제38권5호
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• pp.439-443
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• 2010

The 95% aqueous EtOH extract was obtanied from the fruiting body of Russula subnigricans. Repeated silica gel column chromatography and preparative TLC afforded one fatty acid and three chlorinated hydroquinone derivatives. They were identified as nonadecanoic acid (1), 2,6-dichloro-4-methoxyphenol (2), russuphelin A (3), and russuphelin E (4) on the basis of several spectral data (MS, $^1H$ and $^{13}C$-NMR, including HMBC).

• 한국식품저장유통학회지
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• 제7권1호
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• pp.103-107
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• 2000

Previously , the methanolic extract of peach sees was found to have a strong tyrosinase inhibitory activity in an in vitro assay. Several phenolic compunds were isolated from the seeds by solvent fractionation , Sephadex LH-20 chromatography, and preparative HPLC , and one of them showing strong tyrosinase inhibition was identified as benzoic acid by UV, IR, $^1$H/$^1$$^3$C-NMR, and EI-MS spectrsopy. Benzoic acid (IC50= 250$\mu\textrm{g}$/ml) and L-ascorbic acid (IC50=28$\mu\textrm{g}$/ml), well-known tyrosinase inhibitors. In particular , benzoic acid inhibited markedly the enzymatic browing (melanosis) of apple juices at low concentration of 0.01% and 0.05, comparable to that of L-ascorbic acid (P<0.05). these results suggest that benzoic acid, one of an effective food preservatives, may be potentially useful as a functional alternative to sulfites for the control of melanosis in fruit juices.

• Macromolecular Research
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• 제15권2호
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• pp.134-141
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• 2007

The direct chromatographic separation of enantiomers by chiral stationary phases (CSPs) has been extensively developed over the past two decades, and has now become the most popular method for the analytical and preparative separations of enantiomers. Polysaccharide derivatives coated onto silica gel, as CSPs, playa significantly important role in the enantioseparations of a wide range of chiral compounds using high-performance liquid chromatography (HPLC). Unfortunately, the strict solvent limitation of the mobile phases is the main defect in the method developments of these types of coated CSPs. Therefore, the immobilization of polysaccharide derivatives onto silica gel, via chemical bonding, to obtain a new generation of CSPs compatible with the universal solvents used in HPLC is increasingly important. In this article, our recent studies on the immobilization of polysaccharide derivatives onto the silica gel, as CSPs, through radical copolymerization with various vinyl monomers are reported. Polysaccharide derivatives, with low vinyl content, can be efficiently fixed onto silica gel with high chiral recognition.

• Bulletin of the Korean Chemical Society
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• 제30권2호
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• pp.415-418
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• 2009

Concerned with ambiguous stereochemistry assignment of natural (+)-glabridin, absolute configurations of (${\pm}$)-glabridin enantiomers were studied with synthetic glabridin. Synthetic glabridin enantiomers were separated by semi-preparative Sumi-chiral column chromatography, and characterized by UV-Vis and NMR spectroscopy. Three-dimensional molecular structure of glabridin was obtained as equatorial Ph-3 half chair chroman ring from semi-empirical PM3 calculation, and refined by coupling constants in $^1H$ NMR spectrum. Finally, absolute configurations of two enantiomers were determined by circular dichroism spectroscopy based on the empirical helicity rules. Absolute configuration of natural (+)-glabridin was confirmed as (R)-glabridin, as known.

• 한국식품영양과학회지
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• 제29권1호
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• pp.106-110
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• 2000

We investigated the active oxygen scavenging activity and active compound from Humulus japonicus. The ethyl acetate and butanol fraction exhibited strong scavenging effects on hydroxyl radical. Furthermore active compound was isolated and purified using Amberlite XAD-2 column chromatography and preparative HPLC from ethyl acetate fracton, and major compound was identified as a luteolin-7-O-$\beta$-D-glucoside by the MS, UV, 1H-NMR and 13C-NMR analyses. Luteolin-7-O-$\beta$-D-glucoside exhibited strong scavenging effect on active oxygens such as superoxide radical, hydroxyl radical and hydrogen peroxide.

• 한국동물학회지
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• 제37권1호
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• pp.66-75
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• 1994

Juvenile hormone binding protein was identified in the hemolymph of fifth instar larvae and purified using column chromatography. Hemolymph was mixed with [3H] JH-III and electrophoresed on 691 NON-SDS gel, indicating that radioactivity peak appears at Rf value of 0.55. Gel filtration showed two radioactivity peaks equivalent to bound and free [3H]JH-III, respectively. JHBP was purified from hemolymph through gel filtration (Sephadex G-100), anion exchange chromatosraphv (DEAE Sepharose CL-6B), chromatofocusing chromatographv (PBE 94) and preparative electrophoresis.

• 한국동물학회지
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• 제19권2호
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• pp.63-70
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• 1976

免疫抗體分子의 基本 構造成分인 H-chain, L-chain외에 重合抗體分子 속에서만 발견되는 이른바, J-chain의 構造와 機能을 밝히기 위한 前段階로 J-chain의 純粹分離를 試圖하였다. 우선 多發性骨髓腫 患者의 血淸으로부터 重合型 IgA를 純粹分離한후, 이를 환원시켜 L-J-chain 混合物을 얻은 다음 3가지 方法, 1) 제조용 디스크 전기영동법 2) 脫鹽 透析法, 3) 이온-교환 크로마토그라피법으로 J-chain을 순수분리할 수 있었다. 위 3가지 방법으로 분리한 J-chain의 物理化學的 및 生化學的 성상은 동일하였으며, 사용한 세가지 방법 중 脫鹽 透析法이 가장 간편하고 효과적인 方法임을 알았다.

• Natural Product Sciences
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• 제29권1호
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• pp.17-23
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• 2023

A phytochemical investigation of the fruits extract of Melia toosendan afforded the isolation of two new nor-neolignans, meliasendanins E (1) and F (2), as well as twelve known compounds (3 - 14) using various separation technique such as Diaion HP20, silica, RP-18 gel column chromatography and semi-preparative HPLC. Their chemical structures were elucidated by extensive NMR spectroscopic data including 2D-NMR, and HR-ESI-MS as well as ECD data. Among the twelve known compounds, the absolute structures of 3 - 6 were determined first, and given the trivial names as meliasendanins G-J (3 - 6). Based on the evaluation of anti-inflammatory activity, compounds 7 - 8 exhibited inhibitory effects on LPS-induced nitric oxide production in RAW 264.7 macrophages with IC₅₀ values of 34.6 and 39.5 µM, respectively.

• Applied Biological Chemistry
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• 제38권4호
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• pp.293-296
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• 1995

무화과잎의 메탄올추출물을 용매분획하여 얻은 분획중 산성 분획과 페놀성 분획이 항미생물 활성이 강한 것으로 나타났고 페놀성 분획이 산성 분획보다 항미생물 활성이 더 강하여 페놀성 분획중의 항미생물 활성물질을 동정하기 위하여 먼저 silica gel column chromatography, RP-8 column chromatography 및 preparative liquid chromatography를 행하여 정제하였고 정제된 항미생물 활성물질을 IR, $^{1}H-NMR$ 및 MS에 의한 기기분석을 통하여 동정한 결과 각각 psoralen, bergapten, umbelliferone 및 ${\beta}$-sitosterol로 구명되었다.