• KOREAN JOURNAL OF CROP SCIENCE
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• v.49 no.spc1
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• pp.346-351
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• 2004

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.5
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• pp.653-656
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• 2009

This paper is intended as an investigation of the method of extraction and the analysis by high-performance liquid chromatography mass spectroscopy of decursin and decursinol angelate in the dried root of Angelica gigas Nakai. The extracted decursin and decursinol angelate were the purity of >95% using 60% ethanol at $-20^{\circ}C$ for 12 hours by HPLC analysis. Decursin and decursinol angelate were efficiently isolated using recycling HPLC. The purity of isolated decursin and decursinol angelate was identified as 99.97 and 99.40% by HPLC analysis, respectively. The molecular weights of Decursin and decursinol angelate were also identified as m/z=329 ($[M+H]^+$) and m/z=351 ($[M+Na]^+$) by mass spectroscopy.

• Proceedings of the Korean Society of Crop Science Conference
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• 2005.10b
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• pp.308-309
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• 2005

• Journal of Life Science
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• v.18 no.2
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• pp.206-212
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• 2008

The quorum sensing (QS) regulatory network has been the subject of extensive studies during recent years and has also attracted a lot of attention because it both positively and negatively regulates various putative virulence factors, although initially considered to be a specialized system of Vibrio fischeri and related species. In this study, to identify the novel materials which inhibit QS system of microorganisms, extracts of eighteen natural products were tested by bioassay using N-(3-oxohexanoyl)-$_L$-homoserine lactone and N-(3-oxooctanoyl)-$_L$-homoserine lactone synthesized in this experiment and an Agrobacterium tumefaciens NT1 biosensor strain containing a traI::lacZ fusion. The result indicated that the extracts of cabbage, leek, and onion exhibited the QS inhibition activity. Thus, materials contained in the extracts were isolated via recycling preparative HPLC and were purified via a JAIGEL-LS255 column. The common fraction corresponding to a peak of the 83 min point of them quenched the quorum sensing of A. tumefaciens NT1 biosensor strain in ABMM containing X-gal and was designated quorum sensing inhibitor-83 min (QSI-83). The QSI-83 exhibited the heat stability and did not inhibit the growth of A. tumefaciens NTl. Furthermore, thin layer chromatography (TLC) results suggested that these novel materials may be antagonists of N-acyl homoserine lactone or may inhibit the QS autoinducer synthesis by Pseudomonas syringae pv. tabaci.

• Proceedings of the Korean Institute of Resources Recycling Conference
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• 2003.10a
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• pp.196-200
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• 2003

A novel prepurification method was developed aiming at increasing yield and purity, also reducing solvent usage for purification of paclitaxel. The use of a micelle and precipitation in the prepurification process allows for rapid separation of paclitaxel from interfering compounds and dramatically reduces solvent usage compared to alternative methodologies. The prepurification process serves to minimize the size and complexity of the HPLC operations for paclitaxel purification. The process is readily scalable to a pilot plant and eventually to a production environment where multikilogram quantities of material are expected to be produced. As much as possible, the process has been optimized to minimize solvent usage, complexity, and operating costs.

• The Korea Journal of Herbology
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• v.21 no.2
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• pp.1-7
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• 2006

Objectives : The purpose of this study is to isolate tyrosinase inhibitory material from Pinellia ternata and characterize its own structure and activity. Methods : Pinellia ternata (600g) was extracted with 95% methanol (1L) at $37^{\circ}C$ for 4 days, with shaking at 250rpm. The extract was further solvent-fractionated with n-hexane, chloroform, ethylacetate and water. The active fraction was subjected to JAI recycling prep-HPLC JAIGEL GS-320 column. The structure was identified for the active peak with NMR and GC. Results : Tyrosinase was potently inhibited by 95% methanol extracts from Pinellia ternata. The $IC_{50}$ value of the extracts was estimated to be 0.05mg/ml. The extracts was divided into four solvent-fractions, and the most potent tyrosinase inhibition was found in ethylacetate layer. $IC_{50}$ value of ethylacetate fraction was 0.001mg/ml. This fraction was further purified with JAI Recycling Preparative HPLC (Model: LC 9104). The isolated compound showing inhibitory activity was characterized on its chemical structure by NMR and the compound was identified as 3,4-dihydroxybenzaldehyde. $IC_{50}$ was found to be 7.74 ${\mu}M$ which is much lower than that of kojic acid $(66.5{\mu}M)$. Conclusions : The data suggest that 3,4-dihydroxybenzaldehyde isolated and identified from Pinellia ternata is very strong inhibitor to melanin biosynthesis.

• Journal of Microbiology and Biotechnology
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• v.18 no.3
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• pp.520-522
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• 2008

A new compound named soraphinol C (1) was isolated from myxobacteria Sorangium cellulosum KM1001 a soil isolate, together with a structurally related known compound, 4-hydroxysattabacin (2). These compounds were isolated by silica gel column chromatography and recycling preparative HPLC, consecutively. The structures of the compounds were determined on the basis of combined spectroscopic analyses. Compounds 1 and 2 exhibited antioxidant activity as a radical scavenger in the experiment using a hydrophilic free-radical initiator, 2,2'-azobis(2-amidinopropane)dihydrochloride with ORAC values of 0.956 and 0.617, respectively.

• Korean Journal of Medicinal Crop Science
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• v.12 no.3
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• pp.179-182
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• 2004

Bioassay-directed fractionation of the dried roots of Salvia miltiorrhiza led to the isolation of abietane tanshinones, cryptotanshinone and dibydrotanshinone I. Their structures were elucidated using $^1H-\;and\;^{13}C-NMR$, UV, IR and mass spectral analyses. These compounds exhibited a moderate antimicrobial activities against Staphylococcus epidemidis, Staphylococcus aureus, and Staphylococcus pyogene.

• Korean Journal of Pharmacognosy
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• v.34 no.3 s.134
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• pp.246-249
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• 2003

The major polysaccharide, named EAP, was purified from the aerial parts of Eclipta alba by Sepharose CL-2B ion exchange chromatography and recycling HPLC. The molecular weight of EAP was estimated to be 20911.9 D by MALDI-TOF MS. In addition, the sugar composition was determined to be arabinose (23.6%), mannose (24.8%), galactose (12.3%), and glucose (41.3%), respectively, by GC analysis. The EAP decreased the blood sugar level, which was induced by alloxan in rats, dose dependently.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.6
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• pp.1122-1127
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• 1997

Melanoidins, which were higher polymers with intense brown color, were investigated on their decolorization and degradation by ozonolysis. Amino acids linked up with melanoidins were readily separated by depolymerization of melanoidins with ozonolysis. The IR spectra of ozone-untreated MRPs showed a higher peak at $1665cm^{-1}$ (C=N) and $1600cm^{-1}$ (C=C) than the corresponding peaks of ozone-treated MRPs. Ozone-treated melanoidins with molecular weight of above 900 showed the highest nitrogen composition of all melanoidins tested. Ozone-treated melanoidins with molecular weight of 900 to 1000 were separated into five peaks on recycling preparative HPLC chromatogram. Major functional groups in ozone-treated melanoidins with molecular weight of 900 to 1, 000 were -CH$_2$-CO-, -CH$_2$-O- and CH$_2$-.