• Journal of Applied Biological Chemistry
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• v.58 no.2
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• pp.153-155
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• 2015

The root barks of Morus alba L. were extracted with 80% aqueous MeOH, and the concentrated extract was partitioned with EtOAc, n-BuOH, and $H_2O$ fractions. The repeated silica gel, octadecyl silica gel, and Sephadex LH-20 column chromatographies of the EtOAc and n-BuOH fractions led to isolation of four phenolic compounds. The chemical structures of the compounds were determined as norartocarpanone (1), 2',4',7-trihydroxy-(2S)-flavanone (2), methyl ${\beta}$-resorcylate (3), and (Z)-oxyresveratrol-4-O-${\beta}$-$\small{D}$-glucopyranoside (4). Compound 4 was isolated for the first time from the root barks of M. alba L.

• Korean Journal of Food Science and Technology
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• v.31 no.4
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• pp.984-993
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• 1999

The ethanol extracts and its n-hexane fraction of Dystaenia takesimana Kitagawa exhibited growth inhibition on Listeria monocytogenes ATCC 19111, ATCC 19112, ATCC 19113, ATCC 19114 and ATCC 15313. The minimum inhibitory concentration of the ethanol extract and its n-hexane fraction were 50 ppm and below 30 ppm on Listeria monocytogenes respectively. By silica gel column chromatography, the active fraction A8 was obtained from the ethanol extract of Dystaenia takesimana Kitagawa. After three times of column chromatography, the SBD-1 and SBD-2 were separated from the A8 fraction of the ethanol extract of Dystaenia takesimana Kitagawa. Antimicrobial activity of the SBD-l and SBD-2 was lower than that of the A8. And the A8 exhibited growth inhibition on five strains of Listeria monocytogenes at the level of $10{\sim}30$ ppm and the bactericidal effect was confirmed at same the level. The purified antimicrobial active compound was identified as (9z)-heptadeca-l,9-dien-4,6-diyn-3,8-diol, falcarindiol, by EI/MS, $^{1}H-NMR$ and $^{13}C-NMR$.

• Journal of Microbiology and Biotechnology
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• v.26 no.8
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• pp.1383-1391
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• 2016

The fungal strain EML-DML3PNa1 isolated from leaf of white dogwood (Cornus alba L.) showed strong nematicidal activity with juvenile mortality of 87.6% at a concentration of 20% fermentation broth filtrate at 3 days after treatment. The active fungal strain was identified as Aspergillus oryzae, which belongs to section Flavi, based on the morphological characteristics and sequence analysis of the ITS rDNA, calmodulin (CaM), and β-tubulin (BenA) genes. The strain reduced the pH value to 5.62 after 7 days of incubation. Organic acid analysis revealed the presence of citric acid (515.0 mg/kg), malic acid (506.6 mg/kg), and fumaric acid (21.7 mg/kg). The three organic acids showed moderate nematicidal activities, but the mixture of citric acid, malic acid, and fumaric acid did not exhibit the full nematicidal activity of the culture filtrate of EML- DML3PNa1. Bioassay-guided fractionation coupled with ¹H- and ¹³C-NMR and EI-MS analyses led to identification of kojic acid as the major nematicidal metabolite. Kojic acid exhibited dose-dependent mortality and inhibited the hatchability of M. incognita, showing EC₅₀ values of 195.2 μg/ml and 238.3 μg/ml, respectively, at 72 h post-exposure. These results suggest that A. oryzae EML-DML3PNa1 and kojic acid have potential as a biological control agent against M. incognita.

• Korean Journal of Food Science and Technology
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• v.40 no.2
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• pp.129-134
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• 2008

Five antioxidative active substances were isolated from the EtOAc layer (20 g/56.2 g) of Korean black raspberry (Rubus coreanus Miquel) wine (11 L, black raspberry 15.7 kg fresh wt. eq.) by various column chromatography and high performance liquid chromatography (HPLC). Proton nuclear magnetic resonance ($^1H$-NMR) spectroscopy and gas chromatography Electro Ionization-Mass Spectrometry (GC-EI-MS) identified these as 4-hydroxybenzoic acid (1, 0.1 mg), 3,4-dihydroxybenzoic acid (2, 0.3 mg), 4-(2-hydroxyethyl)-phenol (3, 0.6 mg; tyrosol), pyrocatechol (4, 0.3 mg), 3,4,5-trihydroxybenzoic acid ethyl ester (5, 0.6 mg; ethyl gallate). The presence of 1 and 2 in Korean black raspberry has previously been reported. However, the presence of 3-5 in Korean black raspberry, and the identification of 1-5 from the Korean black raspberry wine have never before been reported.

• Korean Journal of Medicinal Crop Science
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• v.15 no.4
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• pp.296-303
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• 2007

Acer tegmentosum (Acereaceae) has been used a source of traditional medicines for the treatment of hepatic disorders in Korea. This research was conducted to determine biofunctional activities of A. tegmentosum stem extract and to identify its bioactive components. Methanolic extract from A. tegmentosum stem was partitioned by using organic solvents, including n-hexane, ethyl acetate, n-butanol, and water. Two compounds were isolated by using an ODS column chromatography from ethyl acetate soluble fraction shown to the strongest antioxidant activity ($RC_{50}=3.15\;{\mu}g/m{\ell}$) among the fractions. The isolated compounds were analyzed by $^1H$ and $^{13}C$ NMR, IR, UV/VIS, MS spectrum data and identified as catechin, ${\rho}-Hydroxyphenethyl$ alcohol $1-O-{\beta}-_D-(6'-O-galloyl)-glucopyranoside$. The compounds have shown strong antioxidant activity, with similar activity to BHA ($RC_{50}=2\;{\mu}g/m{\ell}$). Especially, ${\rho}-Hydroxyphenethyl$ alcohol 1-O-{\beta}-_D-(6'-O-galloyl)-glucopyranoside$ was shown strong anti-lipid peroxidative activity. However, the compounds were not shown antimicrobial activities. In antimicrobial activity assays, ethyl acetate soluble fraction was effective to bacterial inhibition, such as Escherichia coli and Klebsiella pneumonia, with minimum inhibitory concentrations in $125\;{\mu}g/m{\ell}$. Otherwise, antifungal activity against Candida albicans was shown in n-hexane soluble fraction exhibiting $63\;{\mu}g/m{\ell}$ of minimum inhibitory concentration. In anticomplementary activity assays, water soluble fraction was the most effective exhibiting 24% inhibitory activity.

• Korean Journal of Food Science and Technology
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• v.33 no.4
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• pp.401-408
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• 2001

The ethanol extract and n-hexane fraction of Commiphora molmol Engl. showed minimum inhibitory concentration of 50 ppm and 25 ppm, respectively, on 5 strains of Listeria monocytogenes at $32^{\circ}C$. The purified substance, C3-3-2 fraction, was isolated by silica gel column and preparative thin layer chromatography from n-hexane fraction of Commiphora molmol Engl. The C3-3-2 fraction showed a strong bactericidal activity on 5 strains of L. monocytogenes at the concentration of 10 ppm in tryptic soy broth medium. At that concentration, the viable count was reduced $5{\sim}6$ log cycle from initial cell number. The n-hexane fraction of Commiphora molmol Engl. showed strong growth inhibition at the concentration of 25 ppm on Bacillus cereus and Staphylococcus aureus, at 50 ppm in broth on Salmonella enteritidis, and at 500 ppm on Vibrio parahaemolyticus. The purified antimicrobial substance, the C3-3-2 fraction, was identified as m-nonylphenol by on the basis of the $^1H-,\;^{13}C-NMR$ and EI/MS data. For the application test, the C3-3-2 fraction which was purely isolated from Commiphora molmol Engl. at 100 ppm were applied to minced Alaska pollack and ground beef at $32^{\circ}C$ and $5^{\circ}C$. The antimicrobial substances did not reduce L. monocytogenes ATCC 19113 at $32^{\circ}C$, while they reduced L. monocytogenes ATCC 19113 in viable number at $5^{\circ}C$. However, the antimicrobial effect of C3-3-2 fraction in food system was lower than that of broth condition.

• Journal of the Korean Electrochemical Society
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• v.19 no.3
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• pp.69-79
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• 2016

Lithium ion battery with high energy density is expanding its application area to electric automobile and electricity storage field beyond existing portable electric devices. Such expansion of an application field is demanding higher characteristic and stable long life characteristic of an anode material, the natural graphite that became commercialized in lithium ion battery. This thesis produced cathode by using natural graphite anode material, analyzed creation of the cathode SEI film created due to initial reaction by using electrolyte additives, VC (vinylene carbonate), VEC (vinyl ethylene carbonate), and FEC (fluoroethylene carbonate), and considered correlation with the accompanying electrochemical transformation. This study compared and analyzed the SEI film variation of natural graphite cathode according to the electrolyte additive with SEI that is formed at the time of initial filling and cathode of $60^{\circ}C$ life characteristic. At the time of initial filling, the profile showed changes due to the SEI formation, and SEI was formed in No-Additive in approximately 0.9 V through EVS, but for VC, VEC, and FEC, the formation reaction was created above 1 V. In $60^{\circ}C$ lifespan characteristic evaluation, the initial efficiency was highest in No-Additive and showed high contents percentage, but when cycle was progressed, the capacity maintenance rate decreased more than VC and FEC as the capacity and efficiency at the time of filling decreased, and VEC showed lowest performance in efficiency and capacity maintenance rate. Changes of SEI could not be verified through SEM, but it was identified that as the cycle of SEI ingredients was progressed through FT-IR, ingredients of Alkyl carbonate ($RCO_2Li$) affiliation of the $2850-2900cm^{-1}$ was maintained more solidly and the resistance increased as cycle was progressed through EIS, and specially, it was identified that the resistance due to No-Additive and SEI of VEC became very significant. Continuous loss of additives was verified through GC-MS, and the loss of additives from partial decomposition and remodeling of SEI formed the non-uniform surface of SEI and is judged to be the increase of resistance.

• Korean Journal of Food Science and Technology
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• v.31 no.6
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• pp.1667-1678
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• 1999

Certain parts of 190 kinds of medicinal herbs and 171 kinds of original materials of food were extracted by methanol. The extracts were tested their microbial inhibition activities against several food spoilage microorganisms, Micrococcus luteus, Bacillus subtilis, Bacillus cereus, Listeria monocytogenes, Pseudomonas aeruginosa, Salmonella typhimurium, Escherichia coli, Saccharomyces cerevisiae, Candida albicans, Penicillium citrinum, Aspergillus flavus and Aspergillus niger. The methanol extracts of Cornus officinalis, Evodia officinalis, Glycyrrhiza glabra, Salvia miltiorrhiza. Schizandrae fructus, Coptidis rhizoma, aroma hop and bitter hop were shown inhibitory effect on certain species of gram(+) bacteria. Aroma hop and bitter hop were shown inhibitory effect on certain species of gram(-) bacteria. The methanol extract of Salvia miltiorrhiza exhibited a strong antibacterial activities. It was purified by solvent fractionation, silicagel column chromatography, prep. TLC, prep. HPLC. The purified active substance was identified as cryptotanshinone by EIMS, $1^H-NMR,\;{13}^C-NMR$ and DEPT. Cryptotanshinone showed a strong antibacterial activity against gram positive bacteria $(MIC\;:\;3.91{\sim}62.50\;{\mu}g/mL)$. Especially, this compound was the most strong activity against Bacillus subtilis $(MIC\;:\;3.91\;{\mu}g/mL)$.