• Journal of Microbiology and Biotechnology
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• v.28 no.6
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• pp.968-975
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• 2018

In the course of screening for microbes with nematicidal activity, we found that Enterobacter asburiae HK169 displayed promising nematicidal activity against the root-knot nematode Meloidogyne incognita, along with plant growth-promoting properties. Soil drenching of a culture of HK169 reduced gall formation by 66% while also increasing root and shoot weights by 251% and 160%, respectively, compared with an untreated control. The cell-free culture filtrate of the HK169 culture killed all juveniles of M. incognita within 48 h. In addition, the nematicidal activity of the culture filtrate was dramatically reduced by a protease inhibitor, suggesting that proteolytic enzymes contribute to the nematicidal activity of HK169. In order to obtain genomic information about the HK169 isolate related to its nematicidal and plant growth-promoting activities, we sequenced and analyzed the whole genome of the HK169 isolate, and the resulting information provided evidence that the HK169 isolate has nematicidal and plant growth-promoting activities. Taken together, these observations enable the future application of E. asburiae HK169 as a biocontrol agent for nematode control and promote our understanding of the beneficial interactions between E. asburiae HK169 and plants.

• Korean Journal of Pharmacognosy
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• v.41 no.1
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• pp.38-42
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• 2010

Curcumin content of butanol fraction from C. longa was found to be 22.4942% of the highest content. However, in DPPH radical scavenging ability and antibacterial activity against methicillin resistance Staphylococcus aureus(MRSA, CCARM3696), ethylacetate fraction contained 2.5791% of curcumin was exhibited highest activity. In comparison of enhancing antibiotic(ampicillin) effect against MRSA, ethanol extract contained 1.7838% of curcumin showed more strong activity. This indicates that the ethanol extract and some fractions from C. longa can have antibacterial activity and enhancing antibiotic effect possibly without curcumin. Appropriate use of antimicrobial agent was important point prior to the development of new antibiotics. And in that sence, extract and fractions of C. longa were worth using as synergist of antibiotics and natural antimicrobial agent.

• Applied Biological Chemistry
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• v.41 no.4
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• pp.246-250
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• 1998

The cytotoxic activity of methanol extracts of 25 leguminous seeds in vitro was evaluated by sulforhodamine B assay, using the five human solid A549 lung, SK-OV-2 ovarian, SK-MEL-2 melanoma, XF-498 CNS and HCT-15 colon tumor cell lines. The responses varied with both cell line arid leguminous seed used. Extracts of Canavalia lineata and Glycine soja revealed potent cytotoxic activity against A549 arid SK-MEL-2 cell lines. Moderate activity was observed in the extracts of Cassia obtusifolia and Glyeine max var. chungtae, and C. lineata and Vigna angulasis against SK-MEL-2 and HCT-15 cell lines, respectively. The other seed extracts were ineffective against model tumor cell lines. Because of their potent cytotoxic activities, the activity of each solvent fraction from C. lineata and G. soja was determined and the potent activity was produced from their chloroform fractions. As a naturally occurring therapeutic agent, leguminous seeds described could be useful for developing new types of anti-tumor agents.

• Restorative Dentistry and Endodontics
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• v.24 no.1
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• pp.76-87
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• 1999

The effect of retrograde root-end filling materials(IRM, Super-EBA, Vitremer, MTA) on human periodontal ligament fibroblasts and osteoblasts was observed. The cell activities were evaluated by MTT assay, protein assay and alkaline phosphatase activity examination. The results as follows ; 1. After 24hrs culture, both E1 cells & PDL fibroblast adding root-end filling materials were suppressed cell activities but after 48hrs, cell activities were recovered. 2. Cell activity was lowest in Vitremer followed by IRM, MTA, Super-EBA. 3. Cell activity depression by Vitremer was not concerned with pH changes. 4. Protein synthesis by root-end filling materials were not significant difference in Both E1 cell & PDL fibroblasts but protein synthesis were a little increased by Super-EBA. 5. Alkaline phosphatase activity was increased in E1 cell by Super-EBA & MTA but was not significant differences in E1 cell by IRM & Vitremer. Alkaline phosphatase activity was a little depressed in PDL fibroblast by Vitremer. This findings suggest that these root-end filling materials may have important roles in promotion of PDL healing and consequently may be useful for clinical application in apical surgery.

• International Journal of Industrial Entomology and Biomaterials
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• v.35 no.2
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• pp.111-117
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• 2017

Mulberry leaves containing 1-deoxynojirimycin (DNJ) known to be a strong inhibitory effect for ${\alpha}-glucosidase$. Thus, DNJ has been recognized as a potentially important source for prevent or treat hyperglycemia. More effective method for the DNJ high-production is needed because DNJ content of natural mulberry leaf are as low as 0.1%. Many researchers have studied for the DNJ high-production in mulberry leaves such as the harvest season, fermentation using microorganisms, optimal culture conditions, and optimal extraction conditions. In order to provide for useful data that is anticipated at the level of industrial scale, we investigated ${\alpha}-glucosidase$ inhibitory activity, pH value and DNJ content in large-scale based on the optimal culture conditions for mulberry leaf fermentation of small-scale in our previous study. The ${\alpha}-glucosidase$ inhibitory activity, pH value, and DNJ content in this study were measured from the mulberry leaf fermentation broth for 7 days. During mulberry leaf fermentation, the ${\alpha}-glucosidase$ inhibitory activity and DNJ content was increased until 2 to 4 days, but after 4 day was decreased. The pH value showed a decreasing trend up to 2 day, and little changes in 2 to 4 days. However, the pH was started to increase after 4 days.

• Korean Journal of Materials Research
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• v.16 no.10
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• pp.606-613
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• 2006

This study was purposed to evaluate the influence of anodically oxidized film on titanium (Ti) onto MG-63 osteoblast-like cell attachment and activity. Only scratch lines created by polishing were seen in ASR and ANO-1 groups. About $1.5{\mu}m$-thick homogeneous oxide film which has pores of about $0.5{\mu}m$ diameter were formed in ANO-12. The crystalline structure of the oxide films formed by anodization in phosphoric acid electrolyte was $TiP_2O_7$. The total protein amounts of ANO-1 and ANO-12 groups showed higher values of maximum protein amount than that of AS-R group. At 3 days of incubation, total protein amount showed higher value in ANO-2 when comparing to that of AS-R (p<0.05). Based on the results of ALPase activity test, the degree of MG-63 cell differentiation for initial mineralization matrix formation was similar. For all the test groups after 1 day of incubation, MG-63 cells grew healthily in mono-layer with dendritic extensions. After incubation for 3 days, the specimen surfaces were covered more densely by cells, and numerous micro filaments were extruding to the extracellular matrix.

• Korean Journal of Materials Research
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• v.20 no.3
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• pp.117-124
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• 2010

Titanium dioxide ($TiO_2$) particles deposited on different quantitative Fe-treated carbon nanotube (CNT) composites with high photocatalytic activity of visible light were prepared by a modified sol-gel method using TNB as a titanium source. The composites were characterized by BET, XRD, SEM, TEM and EDX, which showed that the BET surface area was related to the adsorption capacity for each composite. From TEM images, surface and structural characterization of for the CNT surface had been carried out. The XRD results showed that the Fe-ACF/$TiO_2$ composite mostly contained an anatase structure with a Fe-mediated compound. EDX results showed the presence of C, O, and Ti with Fe peaks in the Fe-CNT/$TiO_2$ composites. The photocatalytic activity of the composites was examined by degradation of methylene blue (MB) in aqueous solution under visible light, which was found to depend on the amount of CNT. The highest photocatalytic activity among the different composites was related to the optimal content of CNT in the Fe-CNT/$TiO_2$ composites. In particular, the photocatalytic activity of the Fe-CNT/$TiO_2$ composites under visible light was better than that of the CNT/$TiO_2$ composites due to the introduction of Fe particles.

• 한국신재생에너지학회:학술대회논문집
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• 2006.11a
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• pp.316-319
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• 2006

There is a worldwide interest in the development and commercialization of Polymer Electrolyte Membrane Fuel Cells (PEMFCs) for vehicular and stationary applications. One of the major objectives is the reduction of loaded electrode materials, which is comprise of the Pt-based noble metals. In this paper, a novel chemical strategy is described for the preparation and characterization of carbon-supported and surface-alloys, which were prepared by using a successive reduction process. After preparing Au colloid nanoparticles, the deposition of Au colloid nanoparticles occurred spontaneously in the carbon black-dispersed aqueous solution. Then nano-scaled active materials were formed on the surface of carbon-supported Au nanoparticles. The structural and electrochemical analyses indicate that the active materials were deposited on the surface of Au nanoparticles selectively and that an at toying process occurred during the successive reducing process The carbon-supported & surface-alloys showed the higher electrocatalytic activity than those of the particle-alloys and commercial one (Johnson-Matthey) for the reaction of methanol and formic acid oxidation. The increased electrocatalytic activity might be attributed to the effective surface structure of surface-alloys, which have a high utilization of active materials for the surface reaction of electrode.

• International Journal of Industrial Entomology and Biomaterials
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• v.33 no.1
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• pp.24-30
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• 2016

1-Deoxynojirimycin (DNJ) have been extensively investigated for their α-glucosidase inhibitor on postprandial hyperglycemia, and applied in nutraceuticals and medicine for preventing or delaying progression of type 2 diabetes. However, the amount of DNJ in mulberry leaves is low (about 0.1%), therefore, more effective extraction method is needed. This study was performed to develop microbial DNJ for biological methods of DNJ as an alternative to the chemical methods. In this study, we obtained evidence for Bacillus subtilis that produce DNJ in large quantities by high performance liquid chromatography. Inhibition of α-glucosidase activity was determined to DNJ production or non-production. Investigation of the effect of mulberry leaves powder concentration (1~5%), using the DNJ high-production bacteria, provided evidence for microbial mass production of DNJ. When the 4% mulberry leaf powder for 9 days was used, the α-glucosidase inhibitory activity was over the 85%. Also, the results presented in this study confirm DNJ yield's increasement in microbes using the various of nutrients and provide insight of ways to improve DNJ yields in microorganisms.

• International Journal of Industrial Entomology and Biomaterials
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• v.33 no.1
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• pp.31-35
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• 2016

The influence of commonly used steeping times and temperatures about mulberry tea on a-glucosidase inhibitory activity were studied. The effects of product and preparation variables on the in-cup chemical composition of mulberry tea extracts is of interest because the appearance and taste characteristics and the possible health effects of a tea liquor arise from the chemical components extracted from the leaf during mulberry tea preparation. A comprehensive study was therefore undertaken to determine the contributions of product and provide a basic data for development of high quality mulberry tea products against diabetes. Specific eight mulberry tea were collected from each region of Korea (A-I) and when it was extracted on 85℃ for 2min, a-glucosidase activity was best for 98-102%. According to various temperature and time extraction methods, this study was carried out to optimize teamaking conditions for maximal DNJ extraction from Korean mulberry tea and and it would be of particular interest for people who drink mulberry tea to control blood glucose levels.