• 한국해양바이오학회지
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• 제2권3호
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• pp.187-191
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• 2007

The radical scavenging activity of methanol extracts of seaweeds and their active compounds, alginic acid, fucoidan and phloroglucinol, were investigated under in vitro. Among methanol extracts of seaweeds (sea mustard, sea tangle, seaweed papulosa, fusiforme, sea lettuce, purple laver and chlorella), seaweed papulosa and sea tangle showed strong scavenging activities of 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and hydroxyl radical (${\cdot}OH$). In addition, under in vitro, the scavenging activities on DPPH radical of alginic acid and fucoidan, which are active compounds of brown algae, and phloroglucinol, the active compound from Ecklonia species, were evaluated and compared. Fucoidan and phloroglucinol showed strong DPPH scavenging effect, in particular, phloroglucinol had strongest activity among the active compounds. On the other hand, alginic acid did not exert DPPH scavenging activity. From the present study, we could confirm the antioxidative activity of seaweeds and its active compounds.

• Journal of Microbiology and Biotechnology
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• 제6권4호
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• pp.265-269
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• 1996

An isolate of Streptomyces rochei synonym was found to produce antibiotics with narrow anti-microbial spectrum against Streptococcus and Xanthomonas sp. Among the antibiotic complex produced by the strain, the main active compound was isolated, and its physico-chemical properties and biological activities were investigated. Molecular weight of the compound was determined to be ${[M+H]}^+$ 797 (FAB-MS). UV, $^1H \;and\;^{13}C$ NMR, and IR spectra suggested that the compound is a kirromycin-like aurodox group antibiotic. However, the anti-microbial spectrum of the main compound was slightly different from that of kirromycin. In addition, it was newly found that kirromycin showed a selective anti-microbial activity against Streptococcus pyogenes and phytopathogenic Xanthomonas sp.

• 한국정밀공학회지
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• 제19권6호
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• pp.109-118
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• 2002

The vibrational intensity and the dynamic response of a compound vibratory system had been controlled actively by means of a feedforward control method. A compound vibratory system consists of a flexible beam and two discrete systems - a vibrating source and a dynamic absorber. By considering the interactive motions between discrete systems and a flexible beam, the equations of motion for a compound vibratory system were derived using a method of variation of parameters. To define the optimal conditions of a controller the cost function, which denotes a time averaged power flow, was evaluated numerically. The possibility of reductions of both of vibrational intensity and dynamic response at a control point located at a distance from a source were fecund to depend on the positions of a source, a control point and a controller. Especially the presence of a dynamic absorber gives the more reduction on the dynamic response but the less on the vibrational intensity than those without a dynamic absorber.

• 한국미생물·생명공학회지
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• 제24권5호
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• pp.540-545
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• 1996

A facultative anaerobe Enterococcus faecium 19-46-4 was used to study the production of an antimicrobial substance in anaerobic conditions. Major part of the antibiotic activity was found in the culture filtrate of the bacterium. The active compound was extracted by an equal volume of iso-butanol and concentrated in vacuo (at 50$\circ$C) before purification by C-18 liguid column chromatography and HPLC. A chromatographically pure compound was obtained by two passages of HPLC columns, The compound appeared as a pale-yellow powder. The yield was about 2.5 mg 1$^{-1}$ culture filtrate. The compound was named as KIST 194. KIST 194 were identified as cholic acid (3$\alpha$, 7$\alpha$, 12$\alpha$-trihydroxy-5$\beta$-cholan 24-oic acid) based on its physico-chemical properties determined by UV, IR, $^{1}H-NMR, $^{13}$C-NMR, El-MS and LC-MS.

• Journal of Applied Biological Chemistry
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• 제42권4호
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• pp.197-201
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• 1999

Antagonistic bacteria active against phytopathogenic fungi, Phytophthora capsici, Pythium ultimum, Rhizoctonia solani, Botrytis cinerea, and Fusarium oxysporum were isolated from greenhouse soils. An antifungal compound was extracted by ethyl acetate from acidified culture filtrate and purified through column chromatography and thin layer chromatography. Activity-guided bioassay was followed throughout the purification steps using Pythium ultimum as a test organism. The purified antifungal compound was identified as phenylacetic acid (PAA) based on the data obtained from IR, EI/MS, $^1H-NMR$, and $^{13}C-NMR$. Two different isolates, which had vast differences in differential characteristics except 16S rDNA sequence homology, produced the same compound, phenylacetic acid. $ED_{50}$ values of the phenylacetic acid against P. ultimum, P. capsici, R. solani, B. cinerea, and F. oxysporum were 45, 21, 318, 360, and 226 ppm, respectively.

• Bulletin of the Korean Chemical Society
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• 제33권5호
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• pp.1597-1602
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• 2012

In this study, we determined the 3D-structure of Arabidopsis thaliana KAPAS by homology modeling. We then investigated the binding mode of compounds obtained from in-house library using computational docking methods. From the flexible docking study, we achieved high dock scores for the active compounds denoted in this study as compound $\mathbf{3}$ and compound $\mathbf{4}$. Thus, we highlight the flexibility of specific residues, Lys 312 and Phe 172, when used in active sites.

• 한국미생물·생명공학회지
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• 제22권4호
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• pp.382-388
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• 1994

In the course of screening for insecticidal metabolites from soil microorganisms, Actinomycetes isolate no.1166 was found to produce active metabolites against Musca domestca and Bombyx mori. Three active components from the metabolites were isolated by solvent extraction and chro- matographic techniques and examined their insecticidal activities on Bombyx mori (3rd larvae) by diet feeding bioassay methods. By UV and NMR data analyses, compound I and III were identified as bafilomycin A$_{2}$ and B$_{1}$, respectively and compound II was also estimated to belong to the bafilomycin family from its physico-chemical data and biological properties.

• 미생물학회지
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• 제12권2호
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• pp.77-84
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• 1974

In order to study 5-nitro-2-furaldehyde derivatives having more effective antibacterial activity, four new $N^4$-(5-nitro-2-furfurylidene)-$N^1$-substituted sulfanilamides$N^1$-3,4-dimethyl-5-isoxazoyl-$N^4$-5-nitro-2-furfurylidene sulfanilamide, $N^1$-4,6-dimethyl-2-pyrimidyl-$N^4$-5-isoxazoyl-$N^4$-5-nitro-2-furfurylidene sulfanilamide, $N^1$-6-methoxy-3-pyridazinyl-$N^4$-5-nitro-2-furaldehyde with sulfa drugs such as sulfisoxazole, sulfamethazine, sulfamethoxypyridazine, and sulfadimethoxine. All compounds were tested for antibacterial activity in vitro on the following micro-organisms : Staphylococcus aureus, Bacillus subtilis, Escherichia coli, and Proteus vulgaris. Each compound exhibited a fair bacteriostatic activity against each microorganism. Above all, sulfisoxazole derivatives showed higher activity than the others. Each compound was most active against Staphylococcus aureus, whereas least active against proteus vulgaris.

• Journal of Welding and Joining
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• 제34권2호
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• pp.36-45
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• 2016

Recent developing tendency for technologies of high efficient brazing are studied by searching of NDSL, Science Direct, KIPRIS, PCT and so on. Active metal brazing, arc brazing, fluxless brazing, brazing with low melting point, reactive air brazing, laser brazing, laser droplet brazing are investigated. By optimal selecting of the above mentioned technologies, it needs to investigate an economical metallurgical design and the advanced brazing methods. To improve the embrittlement of intermetallic compound at brazing interface, it must be studied the inexpensive variant metals including nonmetals and the heat sources(MIG, TIG, Laser) by hybrid techniques.

• Journal of Acupuncture Research
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• 제23권5호
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• pp.167-175
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• 2006

Objectives : We studied the effects of Radix Asteris herbal acupuncture solution (RAHAS) on the type I hypersensitivity. Methods : In vivo, we measured compound 48/80 induced active systemic anaphylactic shock, anti-DNP IgE induced passive cutaneous anaphylaxis (PCA) and acetic acid induced microvascular permeability using ICR mice. In vitro, we showed effects on cytotoxicity and ${\beta}$-hexosaminidase release from RBL-2H3 cells. Results : In vivo, RAHAS pretreatments at $BL_{13}$ and optional points inhibited active systemic anaphylactic shock induced by compound 48/80 and microvascular permeability increased by acetic acid. PCA was only inhibited by RAHAS pretreatments at $BL_{13}$. In vitro, RAHAS treatments inhibited ${\beta}$-hexosaminidase release. Conclusion : These results suggest that RAHAS may be beneficial in the prevention of type I hypersensitive inflammatory response.