• Journal of Sericultural and Entomological Science
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• v.15 no.1
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• pp.15-25
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• 1973

The author studied the applicability of Furazolidone to the silkworm rearing industry as a useful remedy for certain silkworm diseases, at the silkworm rearing house of the college of agriculture, Seoul national university, during both the spring and the autumn silkworm rearing season of 1972. Discovering the fact that Furazolidone, when put on the mulberry leaves in a powdered form, is eaten along with the leaves by silkworms and thus the systematic administration of Furazolidone to silkworms is possible, the experimenter carried on a series of experiments (1. determining the in vitro antibacterial activity of Furazolidone to four pathogens of silkworm diseases-Bacillus thuringiensis, Aspergillus oryzae, Aspergillus flavus, and Isaria farinosa, 2. observing the prophylactic and therapeutic effect of Furazolidone against the experimental flacherie caused by inoculation of B. thuringiensis, and 3. examining the toxicity of Furazolidone to silkworm larvae). As the results of the experiments the investigator found out the fundamental fact that Furazolidone exerts a good prophylactic and therapeutic effect against flacherie which is the most common and important silkworm disease: Furazolidone, in in vitro test, inhibited completely the growth of B. thuringiensis, the pathogen of bacterial flacherie, at the concentration of 1 ${\mu}$g/mι. with the tube method and at the concentration of 5 ${\mu}$g/mι. with the plate method, and the drug showed an excellent prophylactic effect and a considerably good therapeutic effect, depending on the time of administration, on the 5th instar silkworms inoculated B. thuringiensis, at the tentative dose of 150mg. per 10 silkworms administered once a day for 2 days. For the practical administration of Furazolidone against flacherie, the dose, the time and duration of administration, and the form of preparation, will be investigated more closely.

• Journal of the korean academy of Pediatric Dentistry
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• v.39 no.4
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• pp.366-372
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• 2012

The aim of this study was to compare two commercial root canal medicaments, ProRoot MTA (Dentsply Tulsa, USA) and OrthoMTA (Bio MTA, Korea), by assessing the antimicrobial effects on three selected species commonly found in root canals of infected teeth, namely Enterococcus faecalis, Fusobacterium nucleatum and Staphylococcus epidermidis. Colonies of these bacteria were treated with varied concentrations of ProRoot MTA or OrthoMTA over different lengths of time. The results are as follows : 50, 25 and 12.5 mg/mL of ProRoot MTA or OrthoMTA did not completely inhibit the growth of E. faecalis, but a decreased growth rate was evident in comparison to the control (p < 0.05). 50 mg/mL of both materials successfully eliminated F. nucleatum during the first 24 hours. Regrowth of microbes after 24 hours, however, indicated a diminished effect of ProRoot MTA whereas OrthoMTA showed its continuously sustained antimicrobial actions (p < 0.05). 50 mg/mL of ProRoot MTA and 50, 25 mg/mL of OrthoMTA exerted their full antibacterial actions against S. epidermidis during the first 24 hours. Although the regrowth of colony was observed after 24 hours, the rate of growth was significantly decreased, approximating a complete inhibition (p < 0.05). The present study revealed that OrthoMTA, recently developed in Korea, had antimicrobial activity higher than ProRoot MTA.

• Korean Journal of Microbiology
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• v.43 no.2
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• pp.124-129
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• 2007

We evaluated the use of citrus fruit fermented by lactic acid bacteria, as a feed supplement for flounder (Paralichthys olivaceus) cultivation. For the fermentation, a lactic acid bacterial strain W-44 showing antibacterial activity was isolated from kimchi. From the phylogenetic analysis based on, 16S rDNA sequence, the strain W-44 was identified as Lactococcus lactis. After the fermentation of citrus fruit with L. lactis W-44, the contents of naringenin and hesperetin, bioactive flavonoid aglycones, were increased about ten-fold and six-fold, respectively. The effects of fermented citrus fruit-based feed additives (CFBFA) were tested on the growth of flounder, Paralichthys olivaceus. There were significant differences in average total length and body weight between the experimental and control group. The growth rate of the experimental group fed with the 0.2% CFBFA-supplemented diet was increased 4.5% and 20.9% more than the control group in total length and body weight, respectively. These results suggest that the fermented citrus fruit could be used as a functional feed additive for flounder cultivation.

• Korean Journal of Microbiology
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• v.50 no.1
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• pp.27-32
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• 2014

Autophagy is one of the lysosomal degradation pathways to maintain cellular homeostasis. The damaged proteins or organelles are uptaken through extra- and intra-cellular stress, starvation and infected pathogens, subsequently, autophagosomes are fused with lysosomes to break down the molecules. Salmonella enterica serovar Typhimurium (S. Typhimurium), intracellular bacteria, cause acute gastroenteritis and food poisoning. Given that autophagy induced by S. Typhimurium plays an important role in the cells to control the infection, we identify whether the induction of autophagy with rapamycin, chemical inducer of autophagy, before infection regulates S. Typhimurium infection. After treatment of rapamycin or 3-methyladenine (3-MA), autophagy inhibitor, RAW264.7 cells were infected with S. Typhimurium. Pretretment of rapamycin decreased the growth rate of S. Typhimurium in the cells; otherwise, pretreatment of 3-MA increased the growth rate of S. Typhimurium. The expression of autophagy-related genes was significantly increased in the S. Typhimurium-infected cells pretreated with rapamycin. To examine whether induced autophagy by rapamycin control the infection with increase the production of reactive oxygen species (ROS) and nitric oxide (NO), antibacterial radical substrates were measured in infected cells followed by the treatment with either rapamycin or 3-MA. NO production increased in RAW264.7 cells; otherwise, ROS production remained unchanged during the infection. These findings suggest that inducing autophagy with rapamycin reveals antimicrobial activity as producing NO against S. Typhimurium infection in mouse macrophages.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.4
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• pp.712-718
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• 2000

The alkali extraction of anticoagulant from a clove revealed 3-to 6-fold more effective than hot-water extraction. The highest anticoagulant activity was found with 0.1 N NaOH at 7$0^{\circ}C$. The anticoagulant fractions from a clove, EC-2B and EC-2C were separated by alkali extraction, ethanol precipitation, cetavlon treatment, and ultrafiltration. The anticoagulant activities of these two fractions were, respectively, 6.57 and 8.63 times higher than those extracted with hot-water. As of the sensory evaluation, boiled pork added with EC-2B fraction revealed similar sensory acceptability to raw clove material, while EC-2C fraction had low sensory acceptability due to a mild chemical odor. Antibacterial characteristics against pathogenic microorganism of both fractions were confirmed in the control strain. The inhibitory effect of growth by EC-2B was noticed above 0.016% in S. aureus. Also, EC-2C showed the inhibitory effect at 0.004% in both E. cole and S. aureus control strains.

• Journal of Life Science
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• v.19 no.6
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• pp.720-727
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• 2009

Lyophilized powder (BP2FS) of soybeans fermented with Bacillus polyfermenticus KJS-2 (B. polyfermenticus KJS-2) exhibited in vitro antibacterial activities against eight pathogenic bacteria. BP2FS was used as a fodder additive for Oplegnathus fasciatus (0. fasciatus) culture. One group (UFD) of O. fasciatus was fed a commercial fodder, while another group (FD) was fed the same fodder, but including BP2FS ($6{\times}10^{4}$ cfu $g^{-1}$ fodder), two times daily for 120 days. The mean body weight of the FD group (67.29${\pm}$12.62 g) was higher than that of the UFD group (56.56${\pm}$8.21 g) after 120 days. The survival rate of FD was 80% compared to 40% for the UFD group. Cumulative mortalities in the FD and UFD groups were 18.95% and 60.98% respectively. B. polyfermenticus KJS-2 was isolated from the intestines of the FD group and the number of viable colonies was estimated to be $1.04{\times}10^{4}$ cfu $g^{-1}$. Iridovirus and Vibrio vulnificus was detected in the organs of the UFD group but not in the FD group. All of the infected fish showed typical clinical symptoms of hemorrhage in their tail fins. Dissection of the infected internal organs revealed liver congestion and spleen enlargement - typical symptoms caused by iridovirus infection. These results clearly show that BP2FS is highly beneficial in preventing O. fasciatus from iridovirus infection.

• Journal of fish pathology
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• v.27 no.2
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• pp.107-114
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• 2014

For the treatments and protection of bacterial fish disease, many requirements are needed for aquatic probiotics so that they are effective in aquaculture animals but are also harmless to humans. In the present study, among 17 candidate probiotic bacteria (CPB) obtained from the edible part of the shellfish, Bacillus sp. CPB-St (CPB-St) were selected and in vitro evaluated for the possibility as a probiotic strain for the control of fish streptococcosis which frequently occurs in the olive flounder farms. CPB-St showed inhibitory effects on the growth of various fish pathogenic bacteria, Streptococcus sp., S. parauberis, S. iniae, Lactococcus garvieae and L. piscium by the double layer test ranging about 18~26 mm of clear zone. Inhibitory activity of CPB-St to Streptococcus sp. was observed 6 hours after and the growth of Streptococcus sp. was decreased to 8~55 folds in the co-culture of CPB-St with Streptococcus sp.. The safety of CPB-St to fish and survival of CPB-St in the intestine were assessed in the olive flounder, Paralichthys olivaceus. Fish mortality was not observed in artificial infection with CPB-St for 2 weeks. CPB-St was entirely excreted from the stomach and intestine 24 hours after oral injection. This results indicate that CPB-St has potential applications as a probiotic for the control of fish streptococcosis in aquaculture.

• Korean Journal of Environmental Biology
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• v.24 no.1 s.61
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• pp.38-45
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• 2006

Ecological characteristics of microbial populations inhabiting heavy metal polluted soil were investigated. The samples were collected from 293 sites around an factory and industry at Gyeoungsangbuk-do. We measured the contents of seven heavy metal elements (Cd, Cu, As, Hg, Pb, $Cr^{6+}$, CN), seven sites have been seriously contaminated by mercury and chrome. A quantitative evaluation of microbial populations in mercury and chrome contaminated soil was examined by using plate count method. Bacterial numbers in polluted soil samples ranged from $7.4X10^5\;to\;9.3X10^7\;cfu\;g^{-1}$, about $10\sim100$ fold less than the count for the unpolluted soil. Moulds were not detected in chrome polluted soil. The log values of actinomycetes of each contaminated soil samples were log ranged from 6.18 to 7.52. The ratio of actinomycetes was similar to unpolluted soil. The investigation showed actinomycetes to be the major microbial population inhabiting the mercury and chrome polluted soil. Thirty-one isolates among the total isolates were examined for antibacterial activity. These isolates were identified based on a phylogenetic analysis using 16S rRNA gene nucleotide sequences, they were categorized in three major phylogenetic groups, belong to the Streptomyces (6 strains), Saccharopolyspora (3 strains), Nocardiodes (1 strain). On the phylogenetic tree, the clade consisting of five isolates were distantly related to all of the established Streptomycetes genera, indicating the possibility as members of new species.

• The Journal of Engineering Geology
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• v.22 no.4
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• pp.439-448
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• 2012

The aim of this study is to develop eco-friendly, fundamental technology for vegetative restoration of barren lands using green rehabilitation material, for the stabilization of abandoned mine debris slopes and depository slopes composed of rock fragments. It is expected that such methods would help to improve the negative view of artificial slopes that remain following mining activity, while also contributing to slope stabilization and prevention of the loss of rock fragments and the dispersion of tailings. We tested the tensile strength and tear strength of various materials, including commonly used natural coir material, natural fibers, and synthetic textile materials with enhanced durability. In conclusion, there is the possibility that natural coir can be used as an eco-friendly material in vegetation restoration, while its durability in natural conditions can be improved by controlling the degree of knot convolution and by antibacterial treatment against biodegradation.

• Journal of Oral Medicine and Pain
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• v.34 no.1
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• pp.23-37
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• 2009

The antibacterial effect of phytoncide on Porphyromonas gingivalis, which is the main causative agent of periodontal disease and halitosis, has been reported. However, little is known about its effect on normal oral microflora. The present study was performed to observe the effect of phytoncide on oral normal microflora and the inhibitory effect of surviving resident oral bacteria on P. gingivalis. In this study, saliva from each of 20 healthy subjects was treated with 1% phytoncide from Japanese Hinoki (Chamaecyparis obtusa Sieb. et Zucc.). Surviving salivary bacteria were isolated on blood agar plates and identified by 16S rDNA sequencing. In order to select inhibitory isolates against P. gingivalis, the isolates from the phytoncide-treated saliva were cultured with P. gingivalis. The results were as follows: 1. In general, the number of bacteria in saliva from periodontally healthy subjects was decreased when the saliva was treated with 1% phytoncide. 2. The majority of the salivary bacteria surviving the treatment of phytoncide were S. thermophilus (53%). 3. Most of the surviving salivary bacteria (72.5%) inhibit the growth of P. gingivalis A7A1-28 and P. gingivalis W83 on blood agar plates. 4. Among the surviving S. thermophilus, 85.8% of them were observed to inhibit P. gingivalis strains and 75.8% of the surviving S. sanguinis were inhibitory. Taken together, oral resident bacteria surviving phytoncide, which has been shown to inhibit P. gingivalis, may exert an additional inhibitory activity against the periodontopathic bacterium. Therefore, phytoncide can be used for preventing and ceasing the progress of periodontal disease and halitosis, and thus is expect to promote oral health.