• Natural Product Sciences
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• v.22 no.4
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• pp.225-230
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• 2016

Phytochemical investigation from the stem bark of Beilschmiedia pulverulenta resulted in the isolation of five lignans, (+)-yangambin (1), (+)-sesartemin (2), (+)-excelsin (3), (+)-sesamin (4), and (+)-syringaresinol (5), together with lupeol (6), lupenone (7), ${\beta}-sitosterol$ (8), and ${\beta}-sitostenone$ (9). Their structures were established by the analysis of their spectroscopic (1D and 2D NMR) and spectrometric (MS) data, as well as by comparison with those reported in the literature. The isolated lignans were tested for their anticholinesterase (AChE: acetylcholine esterase and BChE: butyryl cholineesterase) and anti-inflammatory (COX-2: cyclooxygenase-2 and LOX: lipoxygenase) activities. All the isolated lignans (1 - 5) exhibited significant inhibition activities in AChE/BChE and COX-2/LOX assays with $IC_{50}$ values ranging from $168.8-504.2{\mu}M$ and $21.0-59.4{\mu}M$, respectively.

• Bulletin of the Korean Chemical Society
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• v.27 no.1
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• pp.44-52
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• 2006

New organotin(IV) derivatives with general formulae R_2SnL_2 and R_3SnL, where R = methyl, n-butyl, n-octyl and phenyl and HL is either 3-[N-(4-nitrophenyl)amido]-propenoic acid or 3-[N-(4-nitrophenyl)amido] propanoic acid have been synthesized in 1 : 2 and 1 : 1 molar ratio by different methods. The FTIR spectra clearly demonstrated that the organotin(IV) moieties react with [O,O] atoms of the ligands. The bonding and coordination behavior in these complexes are discussed on the basis of multinuclear (^1H,\,^{13}C,\,^{119}Sn) NMR and mass spectrometric studies. Antibacterial, and antifungal screening tests were performed for these compounds and reported here. These values were compared to those of the precursors and it was found that diorganotin(IV) complexes exhibit less activity as compared to triorganotin(IV) complexes . LD_{50} data were obtained by Brine Shrimp assay method. Insecticidal activity was performed for selective compounds by contact toxicity method.

• Journal of Microbiology and Biotechnology
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• v.32 no.3
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• pp.302-306
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• 2022

A chemical investigation of a culture extract from Streptomyces sp. RK85-270 led to the isolation and characterization of two new oxindoles, RK-270D (1) and E (2). The structures of 1 and 2 were determined by analyzing spectroscopic and spectrometric data from 1D and 2D NMR and High-resolution electrospray ionization mass spectrometry (HRESIMS) experiments. Compound 1 exhibited anti-angiogenic activities against human umbilical vein endothelial cells (HUVECs) without cytotoxicity. Results of Western blot analysis revealed that 1 inhibits VEGF-induced angiogenesis in the HUVECs via VEGFR2/ p38 MAPK-mediated pathway.

• Natural Product Sciences
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• v.29 no.1
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• pp.38-41
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• 2023

Two xanthones and 4-phenylcoumarins were isolated from the twigs of Mesua beccariana (Baill.) Kosterm. Among them, one new xanthone, beccarianin A (1), along with 7-isoprenyl-jacareubin (2), mammea A/AA cyclo F (3), and mammea A/BA cyclo F (4). These structures were determined by spectrometric and spectroscopic methods, HRESIMS data, NMR, and UV spectra. Two xanthones (1-2) and two 4-phenylcoumarins (3-4) were evaluated for their cytotoxic effect on the HeLa cells. Compound 1 showed active activity (IC₅₀ = 8.2 µM), and compounds 3-4 showed moderate activity (IC₅₀ = 12.3 and 15.6 µM, respectively).

• Proceedings of the Plant Resources Society of Korea Conference
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• 2010.05a
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• pp.18-18
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• 2010

Glucosinolates(GSLs) are major secondary products($\beta$-thioglucoside N-hydroxysulfates) containing sulfates that are found mainly in Cruciferae family such as cabbage, broccoli, radish, turnip, kale, mustard and rapeseed as the important crops in agronomic and economic aspects. Especially, isothiocyanates(ITCs) have been shown to inhibit carcinogenesis with regulation cancer cell development followed by regulating target enzymes, inducing cell cycle arrest and apoptosis against various human cancer cell lines. Total desulfo(DS)-GSLs of nine type in 210 Korean leaf mustard accessions were isolated and confirmed using electrospray ionization mass spectrometric(ESI-MS/MS) method and DS-GSLs powerful library maked from several reference data. The isolated individual DS-GSLs were identified by removed $\beta$-D-glucopyranose residue ($C_6H_{11}O_5$, MW 163) from MS/MS data. Among them sinigrin(41.7%), glucoiberverin(21.7%) and gluconasturtiin(12.6%) were major components, Especially, despite gluconapin was minor component, accession K046197-1 and K046197-2 showed higher content of 4.11 and 3.31 mg/g(DW), respectively. The total GSLs contents in 210 accessions were ranged from 5.3 to 23.2 mg/g(DW) with a mean value of 13.0 mg/g(DW). As a result of principal component analysis(PCA), the individual GSLs loading plots were composed of three groups and components belonged to each group showed correlationship in quantitative pattern.

• Journal of the Korean Chemical Society
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• v.65 no.4
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• pp.254-259
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• 2021

The purpose of this work is the development of a method for an effective, less expensive, rapid, and simultaneous determination of three phenolic compounds (caffeic acid, gallic acid, and quercetin) widely present in food resources and known for their antioxidant powers. The method relies on partial least squares (PLS) calibration of UV-visible spectroscopic data. This model was applied to simultaneously determine, the concentrations of caffeic acid (CA), gallic acid (GA), and quercetin (Q) in six herb infusion extracts: basil, chive, laurel, mint, parsley, and thyme. A wavelength range (250-400) nm, and an experimental calibration matrix with 21 samples of ternary mixtures composed of CA (6.0-21.0 mg/L), GA (10.0-35.2 mg/L), and Q (6.4-17.5 mg/L) were chosen. Spectroscopic data were mean-centered before calibration. Two latent variables were determined using the contiguous block cross-validation procedure after calculating the root mean square error cross-validation RMSECV. Other statistic parameters: RMSEP, R², and Recovery (%) were used to determine the predictive ability of the model. The results obtained demonstrated that UV-visible spectrometry and PLS regression were successfully applied to simultaneously quantify the three phenolic compounds in synthetic ternary mixtures. Moreover, the concentrations of CA, GA and Q in herb infusion extracts were easily predicted and found to be 3.918-18.055, 9.014-23.825, and 9.040-13.350 mg/g of dry sample, respectively.

• Geophysics and Geophysical Exploration
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• v.18 no.3
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• pp.97-104
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• 2015

KIGAM has surveyed most of the Korean territory since 1982 using airborne gamma-ray spectrometry, and complete the nationwide scale map in the near future. However, since the duration of survey is too long and the conditions of survey is not consistent, the data does not have physical consistency. In addition, the window counts (count/sec) were recorded instead of potassium, uranium and thorium radioelement concentrations. Thus, the data could not be registered to the International Atomic Energy Agency (IAEA) radioelement datum. This limits the usefulness of the data and it is not possible to easily combine surveys into regional compilations or make quantitative interpretations between different survey areas. To solve these problems, we undertook a test baseline survey over Jincheon-Eumseong area, to level the different two sets of data and to map radioelement concentrations. This survey confirms to IAEA radioelement baseline. The method and procedures of data leveling prepared by this study improve the usefulness and usability of the radiometric data, and make it enable to compile the nationwide scale radioelement concentration maps.

• Journal of Microbiology and Biotechnology
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• v.18 no.10
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• pp.1659-1662
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• 2008

Pseudomonas chlororaphis O6 exhibits induced systemic resistance (ISR) against P. syringae pv. tabaci in tobacco. To identify one of the ISR metabolites, O6 cultures were extracted with organic solvents, and the organic extracts were subjected to column chromatography followed by spectroscopy analyses. The ISR bioassay-guided fractionation was carried out for isolation of the metabolite. High-resolution mass spectrometric analysis of the metabolite found $C_{9}H_{9}O_{3}N$ with an exact mass of 179.0582. LC/MS analysis in positive mode showed an $(M+H)^{+}$ peak at m/z 180. Nuclear magnetic resonance ($^{1}H,\;^{13}C$) analyses identified all protons and carbons of the metabolite. Based on the spectroscopy data, the metabolite was identified as 4-(aminocarbonyl) phenylacetate (4-ACPA). 4-ACPA applied at 68.0 mM exhibited ISR activity at a level similar to 1.0 mM salicylic acid. This is the first report to identify an ISR metabolite produced by P. chlororaphis O6 against the wildfire pathogen P. syringae pv. tabaci in tobacco.

• Mass Spectrometry Letters
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• v.8 no.4
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• pp.109-113
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• 2017

Single analytical procedure including extraction, liquid chromatography, and mass spectrometric analysis was evaluated for the simultaneous measurement of lysophospholipids (LPLs). LPLs, particularly, lysophosphatidic acids (LPA) and sphingosine 1-phosphate (S1P) are lipid messengers ubiquitously found in various biological matrix. The molecular species mediate important physiological roles in association with many diseases (e.g. cancer, inflammation, and neurodegenerative disease), which emphasize the significance of the simple and reliable analytical method for biomarker discovery and molecular mechanistic understanding. Thus, we developed analytical method mainly focusing on, but not limited by those lipid species S1P and LPA using reverse phase liquid chromatography-tandem mass spectrometry (RPLC-ESI-MS-MS). Extraction method was modified based on Folch method with optimally minimal level of ionization additive (ammonium formate 10 mM and formic acid). Reverse-phase liquid-chromatography was applied for chromatographical separation in combination with negative ionization mode electrospray-coupled Orbitrap mass spectrometry. The method validation was performed on human blood plasma in a non-targeted lipid profiling manner with full-scan MS mode and data-dependent MS/MS. The proposed method presented good inter-assay precision for primary targets, S1P and LPA. Subsequent analysis of other types of LPLs identified a broad range of lysophosphatidylcholines (LPCs) and lysophosphatidyl-ethanolamines (LPEs).

• Natural Product Sciences
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• v.21 no.2
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• pp.111-121
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• 2015

The root of Panax ginseng, is a Korea traditional medicine, which is used in both raw and processed forms due to their different pharmacological activities. As part of a continued chemical investigation of ginseng, the focus of this research is on the isolation and identification of compounds from Panax ginseng root by open column chromatography, medium pressure liquid chromatography, semi-preparative-high performance liquid chromatography, Fast atom bombardment mass spectrometric, and nuclear magnetic resonance. Dammarane-type triterpenoid saponins were isolated from Panax ginseng root by open column chromatography, medium pressure liquid chromatography, and semi-preparative-high performance liquid chromatography. Their structures were identified as protopanaxadiol ginsenosides [gypenoside-V (1), ginsenosides-Rb1 (2), -Rb2 (3), -Rb3 (4), -Rc (5), and -Rd (6)], protopanaxatriol ginsenosides [20(S)-notoginsenoside-R2 (7), notoginsenoside-Rt (8), 20(S)-O-glucoginsenoside-Rf (9), 6-O-[$\alpha$-L-rhamnopyranosyl(1$\rightarrow$2-$\beta$-D-glucopyranosyl]-20-O-$\beta$-D-glucopyranosyl-$3\beta$,$12\beta$, 20(S)-dihydroxy-dammar-25-en-24-one (10), majoroside-F6 (11), pseudoginsenoside-Rt3 (12), ginsenosides-Re (13), -Re5 (14), -Rf (15), -Rg1 (16), -Rg2 (17), and -Rh1 (18), and vinaginsenoside-R15 (19)], and oleanene ginsenosides [calenduloside-B (20) and ginsenoside-Ro (21)] through the interpretation of spectroscopic analysis. The configuration of the sugar linkages in each saponin was established on the basic of chemical and spectroscopic data. Among them, compounds 1, 8, 10, 11, 12, 19, and 20 were isolated for the first time from P. ginseng root.