• 한국식품과학회지
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• 제32권5호
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• pp.985-990
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• 2000

${\zeta}-Carotene$를 dichloromethane에 용해하고 dry ice 상에서 ozonolysis을 행하였다. Ozonolysis에 의해 생성된 화합물은 silica gel chromatography를 행하여 분획하고, photodiode array detector를 이용하여 ODS-HPLC로 분석하였다. Toluene에 ${\zeta}-carotene$을 용해하고 $37^{\circ}C$, 72시간 자동산화시킨 결과, 다수의 carbonyl 및 acidic화합물이 생성되었다. ${\zeta}-Carotene$의 자동산화로부터 생성된 carbonyl 화합물의 대부분은 ozonolysis에 의하여 얻어진 산화개열산물이 나타내는 HPLC상의 거동과 분광학적 특성이 서로 잘 일치하였다. 또한 ${\zeta}-carotene$의 자동산화에 의해 생성된 중앙개열 acidic 화합물은 생물활성을 나타내는 4,5-didehydrogeranyl geranyl acid 표준품과 동일한 분광학적 특성을 나타냈다. 이러한 결과는 in vitro상의 산화적 조건하에서 ${\zeta}-carotene$ 자동산화에 의해 eccentric cleavage가 생성됨을 알 수 있었다.

• 한국환경농학회지
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• 제15권1호
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• pp.37-45
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• 1996

수도재배환경(水稻栽培環境) 및 현탁배양세포(懸濁培養細胞) 조건에서 생성된 PCP의 수용성대사물(水溶性代謝物)을 확인에 필요한 정보를 확보하기 위해서 이를 여러 chromatography로 충분히 정제한 다음 이것의 aglycons과 glycon(전보(前報)에서 ${\beta}-glucose$ conjugates인 것으로 추정)을 GC/MS로 분석, 동정하였다. Glycon, 즉 대사물의 polar부위(endocon)가 glucose임을 확인하므로써 전보에서 효소특이성을 통해 추론한 것을 입증할 수 있었다. 또한 conjugates의 source에 따라 다르기는 하였지만 배양세포에서의 aglycon(exocon)s는 주로 PCP, tetrachlorophenol이성체 및 tetra chlorocatechol을, 그리고 수도재배환경에서는 이 외에도 2,4,5- 및 2,4,6-trichlorophenol을 각각 확인할 수 있었다. 이러한 사실은 PCP glucose conjugates의 구조는 PCP뿐만 아니라 이것의 대사물인 Polychlorinated phenols가 개별적으로 glucose와 ${\beta}-anomeric$ conjugation을 이루고 있는 것으로 판단할 수 있었다. 그리고, 대사초기에 이미 여러 종류의 aglycon이 생성되는 것으로 보아 PCP자체도 빠르게 PCPs로 전환되는 것을 알 수 있었다.

• 한국환경농학회지
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• 제34권2호
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• pp.139-148
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• 2015

BACKGROUND: The aim of this study was to isolate and identify algicidal bacterium that tends to kill the toxic dinoflagellate Alexandrium catenella, and to determine the algicidal activity and algicidal range of algicide. METHODS AND RESULTS: Among of algicidal bacteria isolated in this study, NH-3 isolate was the strongest algicidal activity against A. catenella. NH-3 isolate was identified on the basis of biochemical characteristics and analysis of 16S rRNA gene sequences. The NH-3 isolate showed over 99% homology with Arthrobacter oxydans, and was designated as Arthrobacter sp. NH-3. The optimal culture conditions were $25^{\circ}C$, initial pH 7.0, and 2.0% (w/v) NaCl concentration. The algicidal activity of Arthrobacter sp. NH-3 was significantly increased to maximum value in the late of logarithmic phase. Arthrobacter sp. NH-3 showed algicidal activity through indirect attack, which excreted active substance into the culture filtrate. When 10% culture filtrate of NH-3 was applied to A. catenella, 100% of algal cells were destroyed within 30 h. In addition, the algicidal activities were increased in dose and time dependent manners. The pure algicide was isolated from the ethyl acetate extract of the culture filtrate of NH-3 by using silica gel column chromatography and high performance liquid chromatography (HPLC). We investigated the algicidal activity of this algicide on the growth of harmful algal bloom (HAB) species, including A. catenella. As a result, it showed algicidal activity against several HAB species at a concentration of $100{\mu}g/mL$ and had a relatively wide host range. CONCLUSION: Taken together, our results suggest that Arthrobacter sp. NH-3 and its algicide could be a candidate for controlling of toxic and harmful algal blooms.

• Applied Biological Chemistry
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• 제10권
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• pp.47-61
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• 1968

Rhizopus nigricans에 감염(感染)된 고구마의 생화학적(生化學的) 성질(性質)을 구명(究明)하기 위하여 연부(軟腐)고구마로부터 이상대사산물(異常代謝産物)을 분리(分離)하고 그 성질(性質)에 관(關)하여 실험(實驗)한 결과(結果)를 다음과 같이 요약(要約)한다. 1. 건전(健全)한 고구마에는 없는 이상대사산물(異常代謝産物)로서 19개(個)의 Ehrlich's 시약(試藥)에 대(對)한 양성반응성질(陽性反應性質)과 3개(個)의 형광성물질(螢光性物質)의 존재(存在)를 박층(薄層)크로마토그라프로 확인(確認)하였다. 2. 이상대사산물중(異常代謝産物中)에는 그 생성량(生成量)이 가장 많은 물질(物質)로서 Ipomeamarone과 Umbelliferone을 분리(分離)하고 이들의 정제(精製)와 동정(同定)을 행(行)하였다. 3. Ipomeamarone과 Umbelliferone의 경시적(經時的) 생성량(生成量)을 관찰(觀察)하고 이들의 가능(可能)한 생합성(生合成) 경로(經路)에 관(關)하여 고찰(考察)하였다. 4. 연부(軟腐)고구마의 이상대사산물중(異常代謝産物中) Ipomeamarone과 이의 유사물질(類似物質)은 ${\alpha}-amylase$에 대(對)한 활성(活性)을 저해(抵害)하였으며 그 저해형(抵害型)은 비경쟁적(非競爭的)이었다. 5. 연부(軟腐)고구마로부터 분리한 Ipomeamarone은 Yeast의 호흡(呼吸)을 촉진(促進)시켰으며 산화적(酸化的) 인산화반응(燐酸化反應)의 연합해제제(聯合解除劑)인 2, 4-dinitrophenol과 동일(同一)한 효과(效果)를 나타내었다.

• 대한약침학회지
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• 제20권2호
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• pp.119-126
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• 2017

Objectives: Semecarpus anacardium Linn. is a plant well-known for its antimicrobial, antidiabetic and anti-arthritic properties in the Ayurvedic and Siddha system of medicine. This has prompted the screening of this plant for antibacterial activity. The main aims of this study were to isolate compounds from the plant's seeds and to evaluate their antibacterial effects on clinical bacterial test strains. Methods: The n-butanolic concentrate of the seed extract was subjected to thin layer chromatography (TLC) and repeated silica gel column chromatography followed by elution with various solvents. The compound was identified based on observed spectral (IR, $^1H$ NMR, $^{13}C$ NMR and high-resolution mass spectrometry) data. The well diffusion method was employed to evaluate the antibacterial activities of the isolated acyclic isoprenoid compound (final concentration: $5-15{\mu}g/mL$) on four test bacterial strains, namely, Staphylococcus aureus (MTCC 96), Bacillus cereus (MTCC 430), Escherichia coli (MTCC 1689) and Acinetobacter baumannii (MTCC 9829). Results: Extensive spectroscopic studies showed the structure of the isolated compound to be an acyclic isoprenoid ($C_{21}H_{32}O$). Moreover, the isoprenoid showed a remarkable inhibition of bacterial growth at a concentration of $15{\mu}g/mL$ compared to the two other doses tested (5 and $10{\mu}g/mL$) and to tetracycline, a commercially available antibiotic that was used as a reference drug. Conclusion: The isolation of an antimicrobial compound from Semecarpus anacardium seeds validates the use of this plant in the treatment of infections. The isolated compound found to be active in this study could be useful for the development of new antimicrobial drugs.

• The Plant Pathology Journal
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• 제15권1호
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• pp.14-20
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• 1999

Twenty isolates of Helminthosporium species were obtained from various grass plants and tested for controlling efficacy on the development of plant diseases. An isolate of Helminthosporium sp. TP-4 was chosen and six antibiotic substances were purified from cultures of the fungus by repeated silica gel column chromatography and preparative thin-layer chromatography. They were identified as ophiobolin a, 6-epiophiobolin A, 3-anhydroophiobolin A, 3-anhydro-6-epiophiobolin A, iphiobolin B, and iphiobolin I mainly by mass spectrometry and nuclear magnetic resonance spectrometry. Ophiobolins inhibited the growth of a grampositive bacterium Streptomyces griseus, but were not active against gram-negative bacteria. They also showed an antifungal activity. In in vivo tests, iphiobolin B exhibited potent controlling activities against rice blast, tomato late blight, and wheat leaf rust with control values more than 90% and 70% at concentration of $500\mu\textrm{m}$/ml and 100 ${\mu}{\textrm}{m}$/ml. Ophiobolin A and 6-epiophiobolin A controlled the development of wheat leaf rust more than 80% at concentrations of 100 /ml and $500\mu\textrm{m}$/ml respectively. 3-Anhydro-6-epiophiobolin A was not active against any plant disease. On the other hand, the A-series ophiobolins other than 3-anhydroophiobolin A showed stronger phytotoxic activity in a leaf-wounding assay using 8 plant species than those of 3-anhydroophiobolin A, ophiobolin B, and ophiobolin I. The results indicate that there is little correlation between antifungal activity and phytotoxicity of ophiobolins.

• Journal of the korean society of oceanography
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• 제36권4호
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• pp.101-108
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• 2001

Polybrominated diphenylether (PBDEs) congeners, 2,4,4'-TrBDE, 2,2',4,4'-TeBDE, 2,2',4,4',5-PeBDE, 2,2',4,4',5,5'-HXBDE, and 2,2',4,4',5,6-HxBDE, were measured in sediments from 52 stations in the southeastern coastal areas of Korea. Sediment samples were analyzed using gas chromatography coupled to mass spectrometer detector (GC/MSD) with positive electron impact (PEI) mode. New analytical methodology for PBDEs by the isotope dilution method was established using a multi-layer silica gel column chromatography. Total PBDEs levels in sediments for Pohang coast ranged from 1,1 to 33.8 ng/g dry weight (mean 5.3 ng/g dry), from 1.6 to 36.4 ng/g dry weight (mean 5.7 ng/g dry) for Ulsan coast, from 0.8 to 20.3 ng/g dry weight (mean 4.9 ng/g dry) for Busan coast, and from 0.8 to 10.3 ng/g dry weight (mean 4.4 ng/g dry) for Jinhae Bay. PBDEs contamination in surface sediments from Korean southeastern coasts was relatively moderate in comparison to that of other marine environment in the world. The predominant PBDE congeners were 2,2',4,4'-TeBDE and 2,2',4,4',5-PeBDE.

• Journal of Microbiology and Biotechnology
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• 제15권5호
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• pp.1001-1010
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• 2005

Bacillus megaterium KL39, an antibiotic-producing plant growth promoting rhizobacterium (PGPR), was selected from soil. The antifungal antibiotic, denoted KL39, was purified from culture filtrate by column chromatography using Dion HP-20, Silica gel, Sephadex LH-20, and prep-HPLC. Thin layer chromatography, employing the solvent system of ethanol:ammonia:water=8:1:1, showed the $R_{f}$. value of 0.32. The antibiotic KL39 showed a negative reaction with ninhydrin solution, positive with iodine vapor, and also positive with Ehrlich reagent. It was soluble in methanol, ethanol, butanol, and acetonitrile, but insoluble in chloroform, toluene, hexane, ethyl ether, or acetone. Its UV spectrum had the maximum absorption at 208 nm. Amino acid composition, FAB-mass, $^{1}H-NMR,\;^{13}C-NMR$, and atomic analyses showed that the antibiotic KL39 (MW=1,071) has a structure very similar to iturin E. The antibiotic KL39 has a broad antifungal spectrum against a variety of plant pathogenic fungi including Rhizoctonia solani, Pyricularia oryzae, Monilinia froeticola, Botrytis cinenea, Altenaria kikuchiana, Fusarium oxysporum, and F. solani. An MIC value of $10\;{\mu}g/ml$ was determined for Phytophthora capsici. Macromolecular incorporation studies with P. capsici using radioactive [$^{3}H-adenine$] as the precursor, indicated that the antibiotic KL39 strongly inhibits the DNA biosynthesis of the fungal cell. Microscopic observation of the antifungal action showed abnormal hyphal swelling of P. capsici. The purified antibiotic KL39 was very effective for the biocontrol of in vivo Phytophthora-blight disease of pepper.

• Journal of Ginseng Research
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• 제42권2호
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• pp.199-207
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• 2018

Background: Ginseng is a well-known traditional Chinese medicine that has been widely used in a range of therapeutic and healthcare applications in East Asian countries. Microbial transformation is regarded as an effective and useful technology in modification of nature products for finding new chemical derivatives with potent bioactivities. In this study, three minor derivatives of ginsenoside compound K were isolated and the inducing effects in the Wingless-type MMTV integration site (Wnt) signaling pathway were also investigated. Methods: New compounds were purified from scale-up fermentation of ginsenoside Rb1 by Paecilomyces bainier sp. 229 through repeated silica gel column chromatography and high pressure liquid chromatography. Their structures were determined based on spectral data and X-ray diffraction. The inductive activities of these compounds on the Wnt signaling pathway were conducted on MC3T3-E1 cells by quantitative real-time polymerase chain reaction analysis. Results: The structures of a known 3-keto derivative and two new dehydrogenated metabolites were elucidated. The crystal structure of the 3-keto derivative was reported for the first time and its conformation was compared with that of ginsenoside compound K. The inductive effects of these compounds on osteogenic differentiation by activating the Wnt/b-catenin signaling pathway were explained for the first time. Conclusion: This study may provide a new insight into the metabolic pathway of ginsenoside by microbial transformation. In addition, the results might provide a reasonable explanation for the activity of ginseng in treating osteoporosis and supply good monomer ginsenoside resources for nutraceutical or pharmaceutical development.

• 한국약용작물학회지
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• 제12권5호
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• pp.349-354
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• 2004

The extracts of Pinus densiflora sawdust by n hexane, ethyl acetate and methanol solvent were investigated to identify their mycelial growth inhibition against Lentinus edodes. The yields of n hexane soluble fraction, ethyl acetate-soluble fraction, and methanol soluble fraction from P. densiflora sawdust were obtained 1.36%, 2.21% and 4.03% using organic solvent, respectively. The mycelial growth inhibition of L. edodes was the greatest for n hexane extract, ranging from 36.5% to 47.6% at concentrations of 125 ppm to 1,000 ppm, with the values for all concentrations significantly different from one another. After direct extraction of P. densiflora sawdust using n hexane, ethyl acetate and methanol, each extract was separated into three fractions by silica gel column chromatography and then the fractions were isolated on the values of $R_f$ by thin layer chromatography. The mycelial growth inhibition against L. edodes was recognized in the fractions II (33.5%) and III (37.6%) of n hexane extract, the fraction II (21.4%) of ethyl acetate extract and the fraction II (26.4%) of methanol extract. The fractions III of n-hexane extract showed the highest growth inhibition among the nine fractions of the organic solvent extract.