• The Korean Journal of Mycology
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• v.30 no.1
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• pp.44-49
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• 2002

The study was conducted to isolate and identify insecticidal bacteria for biological control of larvae of mushroom fly, Lycoriella mali, which is one of serious pests to oyster mushrooms during its cultivation period. Among eight bacteria isolated from the soil in the oyster mushroom beds and the dead body of L. mali, two bacteria, Bti-D and Bti-U showed more toxicity with mortality rate than other six-bacteria isolates. The two bacteria showed more toxicity in three instar of the period of development of the mushroom fly than in other instar. Symptoms of the larvae of L. mali infected by the two bacteria developed as follows: at the early infection, the front middle gut changed color to light brown, the middle gut to brown, whole body to black brown, and eventually, the fly died. For the identification of these isolates, cultural and biochemical characteristics by Bergey's manual and Biolog system, cell morphology by TEM, endospore and endotoxin by phase-contrast microscope, and test using 33H antisera were examined. According to the results, these two isolates, Bti-D and Bti-U were identified as Bacillus thuringiensis subsp. israelensis respectively.

• Tuberculosis and Respiratory Diseases
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• v.53 no.5
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• pp.569-576
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• 2002

Background : Chlamydia pneumoniae is one of common causes in upper and lower respiratory infections. Isolating C. pneumoniae from clinical specimens is very difficult due to the characteristics of the organism. Recently, we succeeded in isolating C. pneumoniae from a Korean patient, who suffered from acute pharyngitis. This is the first isolate from a clinical specimen in Korea. Methods : We attained a nasopharyngeal swab from a 22-year-old female patient, and inoculated it on a monolayer of the Hep-2 cell line. After 8 passages, we found the inclusion bodies of C. pneumoniae by an immunofluorescence(IF) test. The species-specific monoclonal antibody IF staining and species-specific PCR were done to confirm the species of the isolate, and electron microscopy was used to characterize the morphology. Results : The isolated was confirmed to be C. pneumoniae by species-specific IF and PCR, and the strain was named LKK-1. The shape of the elementary body was round and with a narrow periplasmic space, as shown by electron microscopy, which is similar to the Japanese strain, but not the Western strain. Conclusion : We succeeded in isolating C. pneumoniae from a 22-year-old patient with acute pharyngitis, which is the first isolate in Korea. In the future, this Korean strain will be useful to the study of C. pneumoniae.

• Nutrition Research and Practice
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• v.9 no.1
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• pp.22-29
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• 2015

BACKGROUND/OBJECTIVES: Recently, anthocyanins have been reported to have various biological activities. Furthermore, anthocyanin-rich purple corn extract (PCE) ameliorated insulin resistance and reduced diabetes-associated mesanginal fibrosis and inflammation, suggesting that it may have benefits for the prevention of diabetes and diabetes complications. In this study, we determined the anthocyanins and non-anthocyanin component of PCE by HPLC-ESI-MS and investigated its anti-diabetic activity and mechanisms using C57BL/KsJ db/db mice. MATERIALS/METHODS: The db/db mice were divided into four groups: diabetic control group (DC), 10 or 50 mg/kg PCE (PCE 10 or PCE 50), or 10 mg/kg pinitol (pinitol 10) and treated with drugs once per day for 8 weeks. During the experiment, body weight and blood glucose levels were measured every week. At the end of treatment, we measured several diabetic parameters. RESULTS: Compared to the DC group, Fasting blood glucose levels were 68% lower in PCE 50 group and 51% lower in the pinitol 10 group. Furthermore, the PCE 50 group showed 2-fold increased C-peptide and adiponectin levels and 20% decreased HbA1c levels, than in the DC group. In pancreatic islets morphology, the PCE- or pinitol-treated mice showed significant prevention of pancreatic ${\beta}$-cell damage and higher insulin content. Microarray analyses results indicating that gene and protein expressions associated with glycolysis and fatty acid metabolism in liver and fat tissues. In addition, purple corn extract increased the phosphorylation of AMP-activated protein kinase (AMPK) and decreased phosphoenolpyruvate carboxykinase (PEPCK), glucose 6-phosphatase (G6pase) genes in liver, and also increased glucose transporter 4 (GLUT4) expressions in skeletal muscle. CONCLUSIONS: Our results suggested that PCE exerted anti-diabetic effects through protection of pancreatic ${\beta}$-cells, increase of insulin secretion and AMPK activation in the liver of C57BL/KsJ db/db mice.

• Microbiology and Biotechnology Letters
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• v.31 no.3
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• pp.277-283
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• 2003

A bacterium producing the extracellular mannanase was isolated from Korean soybean paste. The isolate WL-7 has been identified as Bacillus subtiis on the basis on its 16S rRNA sequence, fatty acid composition, morphology and biochemical properties. The mannanase of culture supernatant was the most active around $55^{\circ}C$ and pH $6.0^{\circ}C$, and retained 90% of its maximum activity at range of pH 5.0∼7.5 and $50∼60^{\circ}C$. The additional carbohydrates including lactose, $\alpha$-cellulose, avicel, locust bean gum (LBG), wheat bran and konjak increased dramatically the mannanase productivity of strain WL-7. Especially, the maximum mannanase productivity was reached to 224 U/ml in LB medium supplemented with both 0.5% LBG and 0.5% konjak, which was approximately 200-folds more than that in LB medium. It was suggested that the increase of mannanase production was owing to induction of mannanase biosynthesis by both LBG and konjak hydrolysates transported following initial hydrolysis by extracellular mannanase during the cell growth.

• Journal of Microbiology and Biotechnology
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• v.16 no.6
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• pp.901-910
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• 2006

Poly(3-hydroxybutyrate) [P(3HB)] is a microbial polyester intracellularly accumulated as distinct granules in numerous microorganisms as an energy and carbon storage material. Recombinant Escherichia coli harboring the heterologous P(3HB) biosynthesis genes accumulates large amounts of P(3HB) granules, yet the granule-associated proteins have not been identified. Therefore, this study reports on an analysis of the P(3HB) granule-associated proteome in recombinant E. coli. Fiye proteins out of 7 spots identified were found to be involved in functions of translation, heat-stress responses, and P(3HB) biosynthesis. Two of the major granule-associated proteins, IbpA/B, which are already known to bind to recombinant proteins forming inclusion bodies in E. coli, were further analyzed. Immunoblotting and immunoelectron microscopic studies with IbpA/B antibodies clearly demonstrated the binding and localization of IbpA/B to P(3HB) granules. IbpA/B seemed to play an important role in recombinant E. coli producing P(3HB) by stabilizing the interface between the hydrophobic P(3HB) granules and the hydrophilic cytoplasm. Thus, IbpA/B were found to act like phasins in recombinant E. coli, as they are the major proteins bound to the P(3HB) granules, affect the morphology of the granules, and reduce the amount of cytosolic proteins bound to the P(3HB) granules.

• Korean Journal of Plant Taxonomy
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• v.42 no.4
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• pp.247-252
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• 2012

Seed morphology in the subtribe Agrimoniinae (Rosaceae) was examined using scanning electron microscopy to identify distinct characters and evaluate their evolution in a phylogenetic framework for five genera in the subtribe: Agrimonia L., Aremonia Neck. ex Nestl., Hagenia J.F. Gmel., Leucosidea Eckl. & Zeyh., and Spenceria Trimen. All genera have one or two mature achenes in a fruiting hypanthium. In the seed coats, the cell shape, size, wall features, and sculpturing vary across genera. Of most significance is the presence of papillae structures in both Agrimonia and Aremonia. Through the mapping of papillae features onto phylogenetic trees, either one or two changes in seed coats are hypothesized. The phylogenetic tree inferred from four nuclear and six chloroplast regions of sequence data suggests that at least two steps of papillae sculpturing on seed coats are required. On the other hand, in the phylogenetic tree of a low-copy nuclear gene, one independent evolutionary step is postulated to explain the current character states. In the latter hypothesis, the seed coat sculpturing also supports a monophyletic relationship for cosmopolitan Agrimonia and European endemic Aremonia. The seed coat sculpturing provides valuable information for inferring phylogenetic relationships at the generic level in the subtribe Agrimoniinae.

• Journal of Species Research
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• v.6 no.2
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• pp.101-118
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• 2017

In an investigation of indigenous prokaryotic species in Korea, a total of 57 bacterial strains assigned to the classes Betaproteobacteria and Gammaproteobacteria were isolated from diverse environments. Samples were collected from fresh water, natural caves, soil, paddy fields, lakes, sea water, jeotgal (fermented seafood), salt flats, soil from abandoned mines, plant roots, digestive organs of both Japanese crested ibis (Nipponia nippon) and Burmese python (Python molurus bivittatus) and tidal flats. From the high 16S rRNA gene sequence similarity (>98.7%) and formation of robust phylogenetic clades with closely related species, it was determined that each strain belonged to an independent and predefined bacterial species within either the Betaproteobacteria or Gammaproteobacteria. There is no official report or publication that describes these 57 proteobacterial species in Korea. Overall, in the class Betaproteobacteria there were 16 species in 12 genera of 4 families in the order Burkholderiales and two species in two genera of one family in the order Neisseriales. Within the class Gammaproteobacteia, there were five species in four genera of four families in the order Alteromonadales, 12 species in 11 genera of one family in the order Enterobacteriales, four species in four genera of three families in the order Oceanospirillales, 11 species in four genera of two families in the order Pseudomonadales, two species in the order Vibrionales and five species in five genera of one family in the order Xanthomonadales. Gram reaction, colony and cell morphology, basic biochemical characteristics, isolation source and strain IDs are described in the species description section.

• Polymer(Korea)
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• v.38 no.4
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• pp.441-448
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• 2014

Polyurethane/melamine phosphate composite foam (MP-PUF) was prepared from poly(adipate)diol/melamine phosphate composite (f=2), polyether-polyol (f=4.6), and PMDI (f=2.5). The thermal properties of MP-PUF such as morphology, closed-cell content, thermal conductivity, and thermal stabilities were characterized. Water was used as a blowing agent, and the composition of melamine phosphate (MP) was maintained at $1.43{\pm}0.3wt%$ of MP-PUF. As the content of water increased, the thermal conductivity of pure polyurethane foam (PUF) decreased, whereas the thermal conductivity of MP-PUF increased. The thermal stabilities of the PUF and the MP-PUF were maximized at 5 php $H_2O$, and then decreased at the higher $H_2O$ contents. The thermal stabilities of MP-PUF were greatly enhanced due to the synergetic effect of MP and urea, which was generated during the blowing process. The temperature of 50% residual mass of MP-PUF increased to $370{\sim}450^{\circ}C$ and the temperature of 30% residual mass exceeded over $700^{\circ}C$. Compared to the PUF, the temperature of 50% residual mass and 30% residual mass were higher than 25 and $70^{\circ}C$, respectively.

• Journal of Digital Convergence
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• v.12 no.6
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• pp.407-414
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• 2014

The aim of this study was to evaluate the photodynamic therapy effects against staphylococci using Photofrin and Radachlorin with Light emitting diode(LED). Experimental methods, The bacterial suspensions containing Staphylococcus aureus and Staphylococcus epidermidis at $1{\times}10^5$ were prepared and diluted to different concentrations of photosensitizer, Photofrin or Radachlorin, on 1.25, 2. 5,5 and $10{\mu}g/ml$. The bacterial suspensions were exposed to 630 and 670 nm LED light at the energy density of 14.4 and $19.8J/cm^2$, respectively. The CFU results of S. aureus and S. epidermidis were showed 33 and 50 colony forming at $5{\mu}g/ml$ of Photofrin, respectively and both of them perfectely were dead at $5{\mu}g/ml$ of Radachlorin. The fluorescent intensity by flow cytometry was showed the increase in the dead cells than the normal cells. In the TEM photograph, the damage of bacterial membrane and the distortion of cell morphology were observed. These results suggest that photodynamic therapy combine with Photofrin and Radachlorin can be applied a new modality for antibacterial therapy.

• Journal of Periodontal and Implant Science
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• v.25 no.3
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• pp.603-613
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• 1995

The purpose of this investigation was to evaluate on the biodegradability, biocompatibility and tissue regenerative capacity of synthetic bioabsorbable membranes in beagle dogs. For animal study, 9 adult beagle dogs were used to examination, on the surgical implantation of membranes and histological analysis. In each animal, the 3rd and 4th premolars of the both sides of the mandible were selected as test teeth. Two types of bioresorbable membranes including "Guidor membrane", "S-membranes" were used to examining for biological activity, and also Gore-tex membranes was used for positive control. Surgically created defects were made in 2 premolars of both sides of the mandible at $3{\times}4mm^2$ in size and tested membranes were implanted in the defected area. A plaque control regimen was instituted with daily tooth brushing with a 0.1% chlorhexidine digluconate during experimental periods. All the experimental animals were sacrificed after 2, 4, and 8 weeks from surgery and undecalcified slides were prepared using the "sawing and grinding" technique described by Donath and Breuner". In biodegradability, all the membranes were started their biodegradation from two weeks after implantation and gradually demolished of their frame morphology from eight weeks. However, demolition of membranes in 8 weeks after implantation was highest in Guidor membranes and followed by S-membranes. Biocompatibilityof two kinds of biodegradable membranes including Guidor and S-mambrane were shown to be well tolerated to the surrounding tissue, and were minimal accumulation of inflammatory cell infiltration around the implanted membranes to compare with Gore-tex membrane. Regeneration of defected alveolar bone was initiated from two weeks of membrane implantation and new bone formation was gradually increased from that time. However, pattern of new bone formation on the defected areas of two kinds of biodegrable membranes was almost similar and quite competitive comparing with Gore-tex membrane. These results implicate that bioresorbable membranes should be highly useful tool for guided tissue regeneration of periodontal defects.