• The Plant Pathology Journal
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• v.28 no.1
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• pp.68-74
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• 2012

Biocontrol microbes have mainly been screened among large collections of microorganisms $via.$ nutrient-rich $in$ $vitro$ assays to identify novel and effective isolates. However, thus far, isolates from only a few genera, mainly spore-forming bacilli, have been commercially developed. In order to isolate field-effective biocontrol microbes, we screened for more than 200 oligotrophic bacterial strains, isolated from rhizospheres of various soil samples in Korea, which induced systemic resistance against the soft-rot disease caused by $Pectobacterium$ $carotovorum$ SCC1; we subsequently conducted in $planta$ bioassay screening. Two oligotrophic bacterial strains were selected for induced systemic disease resistance against the $Tobacco$ $Mosaic$ $Virus$ and the gray mold disease caused by $Botrytis$ $cinerea$. The oligotrophic bacterial strains were identified as $Pseudomonas$ $manteilii$ B001 and $Bacillus$ $cereus$ C003 by biochemical analysis and the phylogenetic analysis of the 16S rRNA sequence. These bacterial strains did not exhibit any antifungal activities against plant pathogenic fungi but evidenced several other beneficial biocontrol traits, including phosphate solubilization and gelatin utilization. Collectively, our results indicate that the isolated oligotrophic bacterial strains possessing induced systemic disease resistance could provide useful tools as effective biopesticides and might be successfully used as cost-effective and preventive biocontrol agents in the field.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.43 no.6
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• pp.373-387
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• 2017

Objectives: The purpose of this study was to introduce our three experiments on bone morphogenetic protein (BMP) and its carriers performed using the critical sized segmental defect (CSD) model in rat fibula and to investigate development of animal models and carriers for more effective bone regeneration. Materials and Methods: For the experiments, 14, 16, and 24 rats with CSDs on both fibulae were used in Experiments 1, 2, and 3, respectively. BMP-2 with absorbable collagen sponge (ACS) (Experiments 1 and 2), autoclaved autogenous bone (AAB) and fibrin glue (FG) (Experiment 3), and xenogenic bone (Experiment 2) were used in the experimental groups. Radiographic and histomorphological evaluations were performed during the follow-up period of each experiment. Results: Significant new bone formation was commonly observed in all experimental groups using BMP-2 compared to control and xenograft (porcine bone) groups. Although there was some difference based on BMP carrier, regenerated bone volume was typically reduced by remodeling after initially forming excessive bone. Conclusion: BMP-2 demonstrates excellent ability for bone regeneration because of its osteoinductivity, but efficacy can be significantly different depending on its delivery system. ACS and FG showed relatively good bone regeneration capacity, satisfying the essential conditions of localization and release-control when used as BMP carriers. AAB could not provide release-control as a BMP carrier, but its space-maintenance role was remarkable. Carriers and scaffolds that can provide sufficient support to the BMP/carrier complex are necessary for large bone defects, and AAB is thought to be able to act as an effective scaffold. The CSD model of rat fibula is simple and useful for initial estimate of bone regeneration by agents including BMPs.

• Natural Product Sciences
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• v.24 no.1
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• pp.66-70
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• 2018

Helminthostachys zeylanica is a rare plant grows in lightly shaded areas. The fern was traditionally used as antipyretic and antiphlogistic agents. This study was aimed to evaluate the antibacterial potential of H. zeylanica on foodborne Bacillus cereus. The chemical composition of its ethanolic extract was also determined. The plant samples were collected at Kampung Kebun Relong, Kedah, Malaysia. The ethanolic extract showed significant inhibitory activity on B. cereus with a sizeable clear zone detected on disc diffusion assay. On broth microdilution assay, the MIC of the extract on B. cereus was 6.25 mg/ml and the MBC was 12.5 mg/ml. The inhibitory activity of the extract on B. cereus was bactericidal. In the growth dynamic study, the antibacterial efficacy of the extract was concentration dependent, where a lower colony forming unit count was obtained with increased extract concentration. The SEM micrograph of extract treated B. cereus cells showed invaginations of cell wall. The bacterial cell structure collapsed after 24 h exposure to the extract. The GCMS analysis of the extract showed that the major constituents of the extract were phenol (36.26%) and quercetin (29.70%). This study is important as it shows the potential use of H. zeylanica as an effective agent to control B. cereus related infections.

• Korean Journal of Poultry Science
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• v.31 no.1
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• pp.37-44
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• 2004

It has been recognized that the hen, like its mammalian counterparts, provides young chicks with antibodies as protection against hostile invaders. This system facilitates the transfer of specific antibodies from serum to egg yolk, and provides a supply of antibodies called immunoglobulin Y(IgY) to the developing embryo and the hatched chick. The protection against pathogens that the relatively immune-incompetent newly hatched chick has, is through transmission of antibodies from the mother via the egg. Egg yolk, therefore, can be loaded with a large amount of IgY against pathogens which can immobilize the existing or invading pathogens during the embryo development or in day-old chicks. Thus, the immunization of laying hens to various pathogens results in production of different antigen-specific IgY in eggs. Egg yolk contains 8∼20 mg of jmmunoglobulins (IgY) per ml or 136∼340 mg per yolk suggesting that more than 30 g of IgY can be obtained from one immunized hen in a year. By immunizing laying hens with antigens and collecting IgY from egg yolk, low cost antibodies at less than $10 per g compared to more than $20,000 per g of mammalian IgG can be obtained. This IgY technology opens new potential market applications in medicine, public health, veterinary medicine and food safety. A broader use of IgY technology could be applied as biological or diagnostic tool, nutraceutical or functional food development, oral-supplementation for prophylaxis, and as pathogen-specific antimicrobial agents for infectious disease control. This paper has emphasized that when IgY-loaded chicken eggs are produced and consumed, the specific antibody binds, immobilizes and consequently reduces or inhibits the growth or colony forming abilities of microbial pathogens. This concept could serve as an alternative agent to replace the use of antibiotics, since today, more and more antibiotics are less effective in the treatment of infections, due to the emergence of drug-resistant bacteria.

• The Journal of the Korean Society for Microbiology
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• v.22 no.4
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• pp.435-443
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• 1987

A total of 30 strains of Candida albicans were examined for susceptibility to amphotericin B and ketoconazole using Sabouraud's dextrose broth, Kimmig broth and Supplemented yeast nitrogen base broth media. Furthermore, the growth curve and colony forming units were checked for use of stationary-phase cells and 2-hour incubation cells in the absence of atifungal agents. The viable counts were determined periodically during incubation by standard plate count techniques. The minimum inhibitory concentrations of amphotericin B for use of stationary phase cells were as follows: SDB, $0.09{\sim}0.97mcg/ml$(0.39mcg/ml); Kimmig broth, $0.19{\sim}0.39mcg/ml$(0.42 mcg/ml) and SYNB, $0.19{\sim}0.39mcg/ml$mcg/ml(0.23mcg/ml). In ketoconazole, MICs were value SDB, $3.12{\sim}25.0mcg/ml$(12.5mcg/ml); Kimmig broth, $12.5{\sim}25.0mcg/ml$ (22.5mcg/ml) and SYNB, $3.12{\sim}12.5mcg/ml$(6.71mcg/ml). The MICs of amphotericin B(0.2mcg/ml cone.) for use of 2-hour incubation cells in absence of AMB were, SDB, $0.04{\sim}0.39mcg/ml$(0.11mcg/ml); Kimmig broth, $0.09{\sim}0.39mcg/ml$(0.18mcg/ml) and SYNB, $0.09{\sim}0.19mcg/ml$(0.14mcg/ml) and in KTZ, the value of MICs were SDB, $3.12{\sim}25.0mcg/ml$(12.22mcg/ml); Kimmig broth, $0.78{\sim}25.0mcg/ml$(11.01mcg/ml) and SYNB, $1.56{\sim}12.5mcg/ml$(3.90mcg/ml). The two-log reductions in CFU per milliliter observed when 2 hour preincubation cells were treated with 0.2mcg/concentrations of AMB and 25.0mcg/ml of KTZ. However, AMB treated cells were restored to growth activity, it suggested that the AMB has no active antifungal activity.

• Journal of Microbiology and Biotechnology
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• v.11 no.3
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• pp.399-405
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• 2001

Urushiol, a natural pro-electrophilic quinone compound, has potential structural characteristics as antitumor chemotherapeutic agents. However, urushiol's use as an antitumor drug has some problems, because it is hardly miscible with an aqueous solution. Purified urushiol is highly viscous and soluble only in strong solvents. for this study, we prepared an urushiol-ethanol micro-emulsion with a unimodal size distribution by high-speed homogenization. This generated effective delivery of urushiol to its action wites, so that we could investigate its cytotoxic activity against cancer cells. Using a colony-forming assay, we were able to show that urushiol selectively inhibited the growth of the ovarian cancer cells PA-1 and 2774 at a concentration of $10^{-6}$, whereas it had only a negligible effect on normal CHO cells at the same concentration. The data suggest that urushiol may have potential as an effective antitumor agent in the treatment of ovarian cancer. In addition, we addressed the question of whether the specific cytotoxic effect of urushiol is linked to apoptosis, by DNA fragmentation and DAPI staining assays. The inhibitory effects of urushiol on the growth of ovarian cancer cells was found to be associated with DNA fragmentation and the fragmented nuclei formation, both of which represent markers for the induction of apoptosis. Therefore, the results suggested that urushiol affected its profound cytotoxicity by triggering apoptosis in ovarian cancer cells.

• Macromolecular Research
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• v.16 no.8
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• pp.704-710
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• 2008

Injectable hydrogels are quite promising materials due to their potential to minimize invasive implantation and this provides versatile fitness irrespective of the damaged regions and facilitates the incorporation of bioactive agents or cells. In situ gel formation through stereocomplex formation is a promising candidate for injectable hydrogels. In this paper, a new series of enantiomeric, four-arm, PEG-PLA block copolymers and their stereocomplexed hydrogels were prepared by bulk ring-opening polymerization of D-lactide and L-lactide, respectively, with stannous octoate as a catalyst. The prepared polymers were characterized by $^1H$ nuclear magnetic resonance (NMR) spectroscopy, Fourier-transform infrared (FT IR) spectroscopy, gel permeation chromatography (GPC) and thermal gravitational analysis (TGA), confirming the tailored structure and chain lengths. The swelling and degradation behavior of the hydrogels formed from a selected copolymer series were observed in different concentrations. The degradation rate decreased with increasing polymer content in the solution. The rheological behavior indicated that the prepared hydrogel underwent in situ gelation and had favorable mechanical strength. In addition, its feasibility as an injectable scaffold was evaluated using a media dependence test for cell culture. A Tris solution was more favorable for in situ gel formation than PBS and DMEM solutions were. These results demonstrated the in situ formation of hydrogel through the construction of a stereocomplex with enantiomeric, 4-arm, PEG-PLA copolymers. Overall, enantiomeric, 4-arm, PEG-PLA copolymers are a new species of stereocomplexed hydrogels that are suitable for further research into injectable hydrogels.

• Elastomers and Composites
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• v.36 no.2
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• pp.102-110
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• 2001

The three types of surfactants such as nonylphenoxy poly(ethylene) ethanol homologues, caster oil poly(ethylene) ethanol homologues, and sodium perfluoroalkyl carboxylates are used to improve the wettability of rubber impression material. Among the surfactants, the usage of sodium perfluoroalkyl carboxylates containing fluoro group resulted in the lowest surface energy of impression material and the result gave the positive effect on the wettability of rubber impression material to teeth. Also, the anti-foaming agents were used to reduce or remove the hydrogen gas generating on the impression material by reaction. In the case of rubber impression material containing sodium perfluoroalkyl carboxylate as a surfactant, it was found that the tear strength of rubber impression material increased over 3 N/mm with the addition of anti-forming agent. Therefore, the anti-foaming agent could contribute to the mechanical property of rubber impression material without the change of surface property.

• Journal of Forest and Environmental Science
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• v.33 no.4
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• pp.322-329
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• 2017

As a result of contemporary environmental concerns, a number of studies from plants' tissues as one of the alternatives to conventional chemicals are increasingly investigated. In tandem with these trends, Lagenaria breviflora (LB) fruit, reputed as antiviral and depilatory agents in the Yoruba folkloric medicine was examined on Vitex doniana wood to ascertain its antifungal activity. Fungicides of 25%, 50%, 75%, and 100% LB fruits formulations (concentrations) were developed through simple one-step mechanical-forming process, including control. In this study, the yield, the chemical compositions, the absorption capacity of the fungicides and wood weight losses (WWL) analysis were evaluated to investigate the antifungal activity of LB fruit on wood. The fruit extract yielded 35.4% of fresh juice weight. LB fruits contained total: alkaloids ($8.78{\pm}0.21mg/mL$), flavonoids ($2.01{\pm}0.02mg/mL$), phenol ($7.42{\pm}0.09mg/mL$), saponins ($11.00{\pm}0.10mg/mL$) and tannins ($5.47{\pm}0.05mg/mL$) contents. All the formulations provided effective protection against the tested wood fungi compared to control. Interestingly, the antifungal activity of 50% and 25% formulations of 6.8% WWL and 9.9% WWL satisfied the excellent fungal resistance class description against white rot fungus (Ganoderma lucidum) and brown rot fungus (Fibroporia vaillantii), respectively according to ASTM D 2017. These results thus, support LB fruit as a strong potential source of natural antifungals for industrial wood production.

• Korean Security Journal
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• no.42
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• pp.251-276
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• 2015

The purpose of this article is to examine Israeli intelligence activity which had contributed to the building of Israel and of its national identity. In the late 19th, the Jews scattered around the world had shared the image of victims shaped in the history of the persecution. In this process, intelligence activity was a staple factor which established the state of Israel; political and religious community. Fighting against Arabs, Israel's intelligence agents had played key role in migrating Jews to Palestine and building their own state. In other words, Intelligence activity was the instrument of implementing political Zionism, Jewish nationalism. Even after independence in 1948, despite the opposition of Arab, Israeli intelligence agencies had persuaded the United States and the Soviet Union to recognize Israel as a member of the international society. Arab countries, nevertheless, had regarded Israel as 'a state to be disappeared', and its national identity was totally denied. However, Israel officially gained recognition for statehood through Arab-Israeli war and summit talks with Egypt. Israel finally restored the 'Promised Land' that is recorded in the Bible and established its identity of a winner. In conclusion, Israeli intelligence agency played a decisive role in founding the nation and even forming the consciousness of the people.