• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.95.2-96
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• 2003

In order to develop a new microbial fungicide for the control of vegetable diseases using endophytic bacteria, a total of 260 bacterial strains were isolated from fresh tissues of 5 plant species. After they were cultured in broth media, their antifungal activities were screened by in vivo bioassays against Botrytis cinerea(tomato gray mold), Pythium ultimum(cucumber damping-off), Phytopkhora infestans(tomato late blight), Colletotrichum orbiculare(cucumber anthracnose), and Blumeria graminis f. sp. hordei(barley powdery mildew). As the results of screening, 38 bacterial strains showed potent antifungal activities against at least one of 5 plant pathogens. A bacterial strain EB072 displayed potent disease control activities against 3 plant diseases. Among the bacterial strains with a potent antifungal activity against cucunlber anthracnose, three bacterial strains, EB054, EB151 and EB215, also displayed a potent in vitro antifungal activity against C. acutatum, a fungal agent causing pepper anthracnose. A bacterial strain EB215 obtained from roots of cucumber was identified as Burkholderia cepacia based on its physiological and biochemical characteristics and 165 rRNA gene sequence. An antifungal substance was isolated from the liquid cultures of B. cepacia EB215 strain by ethyl acetate partitioning, repeated silica gel column chromatography, and invitro bioassay, Its structural determination is in progress by various instrumental analyses.

• Journal of Food Hygiene and Safety
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• v.2 no.4
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• pp.181-189
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• 1987

To find esterase inhibitors and in the metabolites of Streptomyces strain DMC-498, two active compounds were isolated from the methanol extract of the mycelia of the strain by Silica gel column chromatography and preparatory argentation TLC. These compounds were proved to show competitive inhibition. Compound B was found to consist of linoleic and oleic acids. Fifty percent inhibition concentration ($lC_{50}$) of linoleic acid was $0.045\mu\textrm{g}/ml$, whereas oleic acid exhibited no inhibitory activity. Associated lipids: isostearic acid, isostearic acid methyl ester, oleic acid methyl ester and linoleic acid methyl ester, were isolated from the same extract, showing no inhibition of the esterase. Compound A was found to be a liquid inhibitor with an alicyclic ring and two or more oxygens, its molecular weight being more than 500.

• Applied Biological Chemistry
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• v.10
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• pp.47-61
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• 1968

Sweetpotato infected by Soft-rot, Rhizopus nigricans, has been investigated for its biochemical changes. The results of the present experiment are summarized as follows: 1. From the Soft-rotted tuber, nineteen Ehrlich's positive substances and three fluorescent compounds which had not been found in a healthy tuber were detected with thin layer chromatography. 2, Ipomeamarone and umbelliferone, each of which are predominating substances among the Ehrlich's positive and fluorescent compounds, were isolated by silica gel column chromatography and studied for their identities. 3. Time course biosynthesis of the metabolites was studied and discussed for their possible biosynthetic pathways. 4. Among the metabolites, ipomeamarone and ipomeamarone-like substances have enzyme: inhibitive action against ${\alpha}$-amylase and probably other enzymes; the inhibition type was determined as the uncompetitive one. 5. Ipomeamarone obtained from soft-rotted sweetpotato was proved to have an uncoupling action as 2, 4-dinitrophenol.

• Applied Biological Chemistry
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• v.32 no.4
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• pp.338-343
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• 1989

The volatile oil of the root of Codonopsis lanceolata Traut. (Benth. et Hook.) was isolated by steam distillation and extraction method and fractionated by silica gel column chromatography. The total volatile oil and each fractions were analyzed by GG, GC-MS and retention indices matching. A total of 50 components were identified in the volatile oil including 16 terpene and terpene alcohols, 13 hydrocarbons, 5 alcohols, 6 aldehyde and ketones, 6 acids, 2 esters and 2 miscellaneous components. The major components were n-hexanal (7.3% of total volatile oil), trans-2-hexenal (24.9%), n-hexanol (19.8%), cis-3-hexen-1-ol (5.6%) and trans-2-hexen-1-ol (29.4%).

• Korean Journal of Medicinal Crop Science
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• v.8 no.2
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• pp.94-101
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• 2000

On the purpose of development of antioxidative compounds from natural sources, 38 plants known to have antioxidant activity have been examined concerning DPPH radical scavenging activity. Among 13 plants exhibiting the activity, the seed of Carthamus tinctorius L, was selected as resources to search for active compounds due to rareness of study. The seed of the plant has been used as edible oil or preventive and remedial drugs for osteoporosis, arthritis. To reveal the principal component manifesting the antioxidant activity, the MeOH extracts was successively solvent-fractionated with EtOAc, n-BuOH and water. In order to isolate active component from the EtOAc fractions, application of silica gel column chromatographies and activity tests were repeated for a active component to be isolated. Its chmical structure was determined to be N-feruloylserotonin, a conjugated serotonin compound, by the interpretation of spectral data, NMR. MS and the adaptation of chemical reactions.

• Journal of the Korean Ceramic Society
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• v.50 no.2
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• pp.134-141
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• 2013

Pond ash produced from Seochun Power Station was quantitatively characterized to manufacture geopolymers with a range of Si/Al compositional ratios. Mix consistency was kept nearly constant for comparing the compressive strengths of geopolymers. The amorphous composition of coal ash was determined using XRF and quantitative X-ray diffraction. Different mix compositions were used in order to achieve Si/Al ratios of 2.0, 2.5 and 3.0 in the geopolymer binder. Geopolymers synthesized from coal ash with a Si/Al ratio of 3.0 exhibited the highest compressive strength in this study. It was found that geopolymers activated with aluminate produced different microstructure from that of geopolymers activated with silicate. High silica in alkali activators produced the fine-grained microstructure of geopolymer gel. It was also found that high compressive strength was related to low porosity and a dense, connected microstructure. The outcome of the reported experiment indicates that quantitative formulation method made it possible to choose suitable activators for achieving targeted compositions of geopolymers and to avoid efflorescence.

• Journal of Radiation Protection and Research
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• v.18 no.1
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• pp.25-35
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• 1993

To develop a technique of theoretical alpha track density calculation for comparison with measured track density, an electrostatic ion spectrometer was specially designed and fabricated. The mobility spectrum of first radon daughter(Po-218) in the range of $0.07{\sim}5.0cm^2/V\;s$ from the radon chamber was measured using-the electrostatic ion spectrometer. Measurement was taken in a radon chamber operated using dry particle free air passed through silica gel, activated charcoal and molecular sieve filters. The mobility of a new-born Po-218 ion measured by the electrostatic ion spectrometer was determined to be $1.92cm^2/V\;s$. A comparison of the theoretical and measured alpha track densities was completed and uncertainties concerning the shape of the spectrum were analyzed. It was found that the discrepancies in track densities are primarily Que to the neglect of wall loss of ions in the theoretical track density calculation.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.13 no.5
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• pp.217-221
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• 2003

In this work, chemical-solution derived silicate fibers were prepared by mixing tetraethyl orthosilicate, ethanol, distilled water, and hydrochloric acid in order to investigate surface roughness of fiber. Silicate fibers were drawn by using a viscous solution after evaporation at $80^{\circ}C$. The dried gel fibers were finally annealed at $1000^{\circ}C$, $1100^{\circ}C$, $1200^{\circ}C$ and $^1300{\circ}C$ for 60 min in dried air (flow rate = ∼200 ml/min). The crystallinity of the heat-treated silica fiber was analyzed by the X-ray diffraction $\theta$-2$\theta$ scan. A field emission-scanning electron microscope and an atomic force microscope were used to evaluate surface properties. The silicate fiber annealed at $1300^{\circ}C$ showed high value of root mean square roughness and had a relatively inhomogeneous surface structure.

• Microbiology and Biotechnology Letters
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• v.26 no.4
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• pp.283-289
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• 1998

A bacterial strain KH-95 producing a high concentration of red pigment was isolated from the soil. The strain KH-95 was identified as a strain of Serratia sp. based on morphological and physiological characteristics. The optimal temperature and initial pH range for the production of pigment were 28$^{\circ}C$ and 7.0-8.0, respectively. The red pigment was purified through solvent extraction and silica gel column chromatography. Analyzing the structure of this pigment by instrumental analysis, it was identified as prodigiosin-like compound. In optimization of carbon and nitrogen sources, all carbon sources tested in this work inhibited the production of pigment except oils. Casein fumed out to be the most suitable nitrogen source for pigment production. Other nitrogen sources such as yeast extract, beef extract and peptone showed good cell growth but potently inhibited the production of pigment.

• Journal of Pharmacopuncture
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• v.22 no.4
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• pp.239-247
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• 2019

Objectives: Allium jesdianum (Aj) is a medicinal plant that has highlighted pharmacological features. In this study, the effects of Aj extract were examined on acetaminophen (APAP)-induced hepatic failure in rats. Methods: Methanolic fraction of hydro-alcoholic extract of Aj was obtained by silica gel column chromatography method. Animals were randomly divided into four groups each containing six rats and treated by gavage as follows: the first and second groups received normal saline, the third and fourth groups were received with 50 and 100 mg/kg of Aj extract, respectively. After two consecutive weeks, the groups 2-4 were given a single dose of APAP (2 g/kg). After 48 hours, blood and liver samples were collected for biochemical and histological examinations. Results: The findings of the study demonstrated that APAP caused a significant increase in ALT (P < 0.001), AST (P < 0.001), LDH (P < 0.001), ALP (P < 0.001) serum levels, hepatic lipid peroxidation (LPO; P < 0.001) and nitric oxide (NO; P < 0.001). In this regard, APAP led to the depletion of the total antioxidant capacity (TAC; P < 0.001), glutathione and total thiol groups (TTGs; P < 0.001), and structural change in the liver. In the Aj extract groups, a considerable improvement was found in the hepatic function alongside the histopathologic changes. Conclusion: This investigation indicated that the influential effects of Aj extract in APAP-induced hepatic failure might depend on its effect on improving oxidant/antioxidant balance in hepatic tissue.