• Korean Journal of Microbiology
• /
• v.47 no.3
• /
• pp.218-224
• /
• 2011

Lactic acid bacteria (LAB) OA18 was isolated from yogurt prepared by using Kefir Grain as a starter. The OA18 strain was a Gram-positive, cocci-type bacterium, and able to grow anaerobically with $CO_2$ production. The OA18 strain grew well on MRS broth supplemented with 50 mM arginine at $30-37^{\circ}C$ and pH of 7.0-9.0. The optimum temperature and pH for growth are $37^{\circ}C$ and pH 7.0. The isolate fermented ribose, D-glucose, cellobiose, D-trehalose, but not L-xylose, D-melibiose, and inositol. The 16S rRNA gene sequence of the isolate showed 99.8% homology with the Enterococcus faecalis 16S rRNA gene (Access no. AB012212). Based on the biochemical characteristics and 16S rRNA gene sequence analysis data, it was identified and named as E. faecalis OA18. The E. faecalis OA18 strain showed a high ornithine-producing capacity in the presence of arginine and also showed an antimicrobial activity against Streptomyces strains such as Streptomyces coelicolor subsp. Flavus, S. coeruleorubidus, S. coeruleoaurantiacus, S. coelicolor, S. coeruleoprunus. The cell growth of E. faecalis OA18 strain was maintained in MRS broth with a NaCl concentration of 0-7%.

• Korean Journal of Microbiology
• /
• v.47 no.3
• /
• pp.255-262
• /
• 2011

Six protein-degrading bacteria were isolated from digestive organ of Harmonia axyridis. These isolates were categorized as Staphylococcus sciuri subsp. sciuri (3 strains), Bacillus subtilis (1 strain), and Bacillus thuringiensis (2 strains) by 16S rRNA gene sequence analysis. The Staphylococcus sp. CB2-3 was selected as a protease-producing bacterium which showed the highest protease activity of 58.5 U/ml at the pH 5.0 medium. The optimal pH and temperature of protease activity were pH 5.0 and $40^{\circ}C$, respectively. This acid protease had a relatively high stability of 80% between $30-50^{\circ}C$ at broad temperature range. The opimal medium compositions of carbon, nitrogen and mineral source for cell growth and protease activity were investigated. When sorbitol (0.5%) was used as carbon source, enzyme activity was increased about 2 times than that of the basal medium. When skim milk (0.5%) was used as nitrogen source, activity was increased about 2.5 times than that of the control. Cell growth and enzyme activity were increased by mineral source such as KCl, $K_2HPO_4$, $FeSO_4$, but was completely inhibited by divalent ions such as $Co^{2+}$, $Zn^{2+}$, $Mn^{2+}$, $Cu^{2+}$.

• Korean Journal of Microbiology
• /
• v.49 no.1
• /
• pp.90-94
• /
• 2013

A new Bacillus strain designated as MP56 producing antimicrobial substance has been isolated from the mud flat of Korea. The strain MP56 was found to exhibit broad spectrum of antimicrobial activity against Gram-positive pathogenic microorganisms and MDR (multi drug resistant) strains. The 16S rRNA sequence revealed that the MP56 was closely related to Bacillus subtilis with 99.93% homology. The optimal medium composition for production of antimicrobial substance in the B. subtilis MP56 were 1% mannitol, 1% oat meal, 0.01% $CaCl_2$. Antimicrobial activity of the culture broth against different pathogenic strains was assessed using the antimicrobial spectrum. The result suggests that Bacillus strain MP56 produces high quality antimicrobial substance that might be very useful to control varieties of pathogenic microbial growth.

• Korean Journal of Microbiology
• /
• v.49 no.1
• /
• pp.8-16
• /
• 2013

A GAL4 type transcription factor gene (formally annotated as AN3912) locating downstream of sndA (AN3911) was characterized. The putative transcription factor carries both Zn(II)2Cys6 binuclear cluster DNA-binding domain and transcription activator domain. The gene named gtfA (gal4 type transcription factor) had an open reading frame which consisted of 762 amino acids and was disrupted by three introns. The deletion mutant produced reduced amount of conidia but increased amount of fruiting bodies, suggesting that the GtfA make function in decision of asexual preferential to sexual development. The forced over expression of gtfA caused the retardation of fruiting body formation on high glucose concentration. The transcript level of gtfA was kept constant through the life cycle except late vegetative stage and early sexual development stage during which slight increase was found. The expression of gtfA was not significantly affected by sexual or asexual development regulators, such as VeA, NsdD or FluG, FadA, and SfaD. The GtfA repressed the nsdC transcription, which suggested that GftA control sexual development negatively via negative regulation of nsdC expression.

• Applied Biological Chemistry
• /
• v.46 no.1
• /
• pp.60-65
• /
• 2003

MMP-1 inhibitory compounds were isolated from 120 Korean traditional edible plants. UP- 1 activity significantly increased linearly with increasing UVB dose in normal human foreskin fibroblast HS68 cell, showing maximum activity at approximately 35 $mJ/cm^2$, whereas in HaCaT cell, normal human keratinocyte, no increase was observed. Maximum secretion of MMP-1 after UVB treatment occurred around 36-48 k after treatment. MMP-1 inhibitory compound isolated from cold-water fraction of Cataegus pinnatifida Bunge showed the mort potent activity. The MMP-1 inhibitory compound was deduced as a peptide based on the fact that pronase digestion decreased the activity whereas periodate oxidation did not. The most potent UP- 1-inhibitory protein, CP-2Va-2, showing an activity of 88.5% against MMP-1, was isolated through sequential column chromatography on DEAE-Toyopearl 650C, Butyl-Toyopearl 650M, and Bio-Gel P-30. Molecular weight of CP-2Va-2 determined through high performance liquid chromatography and SDS PACE was 19 and 20 kDa. respectively, signifying a monomeric structure.

• Journal of fish pathology
• /
• v.6 no.2
• /
• pp.205-218
• /
• 1993

On the development of hirame(Paratichtys olivaceus) culture, outbreak of scuticociliata infection was reported to cause severe damage in Japan. To establish effective measures for isolation and cultivation of this ciliate, we tried to culture this pathogenic ciliate using medium for bacteria and fish cell lines in vitro. Scuticociliata from the brain tissues of infected fish was aseptically inoculated to CHSE-214 cells cultured in MEM-10 without antibiotic. Scuticociliata grew well and the number of ciliate reached $10^6\;cells/ml$ at temperatures of $15^{\circ}C$ to $20^{\circ}C$ for 10d. The number of ciliate cultured in the cell lines is 10 times higher than the numbers cultured in the liquid medium alone. This ciliata could be cloned by dilution method. Scuticociliata isolated could grow well on 42 different cell lines that were established from marine fish, warm freshwater fish, and salmonids. This ciliate could be preserved in liquid nitrogen for more than 6 months. Subsequently, we observed the optimal temperature and salinity for growth, and tested the sensitivities of this organism to formaldehyde, flagyl(Metronidazole), Ekuteshin(Combination compound of sulfamonometoxin and ormethoprim), and ozonixation. Optimal temperature for growth was $25^{\circ}C$ and salinity was 1.0 to 1.5%. Washed scuticociliata was killed by formaldehyde at the concentration of 50ppm for 10min, but was not completely killed even at a high concentration of 400ppm for 20min in MEM-5. Flagyl and Ekuteshin can inhibit the growth of scuticociliata at the concentration of 1,000 and $100{\mu}g/ml$ in MEM-10, respectively. More than 99% of this scuticociliata could be killed by ozonization at a dose equivalent to $1.0mg/\ell$ oxidant for 30sec in sea water. Isolated scuticociliata showed the pathogenicity to the cultured hirame by artificial infection(I. P. injection, $10^5\;cells$/fish). The number of scuticociliata in the water could be counted by most probable number(MPN) method using tissue culture, and the minimum detectable number was $1.8\;cells/\ell$. The number in the reservoir tank for water supply to the culture tank was 110 cells/l. After cleaning by elimination of the sediments from of the reservoir tank and disinfected with formaldehyde, number of scuticociliata decreased and was counted less than $1.8\;cells/\ell$ and infection rate of cultured hirame was decreased.

• Korean Journal of Remote Sensing
• /
• v.27 no.1
• /
• pp.43-49
• /
• 2011

In the face of growing concern about global warming, increasing attention has been focused on the reduction of carbon dioxide emissions. One method to mitigating the release of carbon dioxide is Carbon Capture and Storage (CCS). CCS includes separation of carbon dioxide from industrial emission in plants, transport to a storage site, and long-term isolation in underground. It is necessary to conduct analyses on optimal site selection, surface monitoring, and additional effects by the construction of CCS facility in Gyeongsang basin, Korea. For the optimal site selection, necessary data; geological map, landcover map, digital elevation model, and slope map, were prepared, and a weighted overlay analysis was performed. Then, surface monitoring was performed using high resolution satellite image. As a result, the candidate region was selected inside Gyeongnam for carbon storage. Finally, the related regulations about CCS facility were collected and analyzed for legal question of selected site.

• Journal of Preventive Medicine and Public Health
• /
• v.36 no.1
• /
• pp.11-23
• /
• 2003

Objectives : The 1990s has seen advances in the conceptualization of self-perceived health status which has important roles for individual health and the quality of life. Many types of standardized questionnaires have been developed with the current wide use of SF-36, NHP, andEuroQol. However, the outcomes of these tools may be different with regard to regional, cultural and emotional backgrounds. The purpose of this study was to trial the development of a Korean Health Profile (KHP 1.0) to measure the self-perceived health stati of Koreans. Methods : The KHP 1.0 was designed on the basis of the Medical Outcome Study Form 36 (SF-36), the Nottingham Health Profile (NHP), and the EuroQOL. It was composed of 9 scales; physical functioning, role limitation-physical, pain, general health, energy, social isolation, sleep, role limitation-emotional, and e-motional health. Self-reported chronic disease conditions, and the Zung's Self-Rating Depression Scale (SDS), were also checked for the evaluation of clinical validity. This study was conducted, from December 2000 to January 2001, on 800 middle-aged parents, with four high school students, with 100 retest sets being conducted two weeks later. From the 800 subjects there were 588 complete responses (effective response 73.5%). The reliability of the test-retest results, and the factor analysis on the validity of the KHP 1.0 components, were evaluated using the SPSS (ver 10.0) software. Results : The reliability of the KHP 1.0 was good with Cronbach's alpha (>0.6), test-retest correlation coefficients (>0.5), but with no significant differences from the paired t-test. From the psychometric validity tests, the 9 scales of the KHP 1.0 were divided into two components; physical and mental, and trimmed to the established model with 55% of the total variance, with the exception of role limitation-emotional. The clinical validity on the basis of the comparison for the four characteristic groups; healthy, physical conditions only, mental conditions only, and physical and mental conditions were also good. Conclusions : The KHP 1.0 appears to be a valid measurement tool of self-perceived health stati of Koreans, although there are limitations, i.e. sample size was too small, a limited number of middle-aged subjects, and it was based on unconfirmed diagnoses, etc. Therefore, further study is required to standardize the assessment.

• Korean Journal of Soil Science and Fertilizer
• /
• v.38 no.1
• /
• pp.25-31
• /
• 2005

A soil bacterium, Bacillus subtilis HJ927, exhibiting strong antagonistic property against pathogenic fungi was isolated from pepper fields infested with Phytophthora capsici. Pepper plants inoculated with P. capsici revealed severe root mortality while plants co-inoculated with B. subtilis HJ927 and P. capsici showed drastically reduced root mortality. Low molecular weight substances released by B. subtilis HJ927 mediated the plant protective effect. The anti-fungal compounds released by B. subtilis HJ927 were identified as 3-methylbutyric acid, 2-methylbutyric acid, and methyl 2-hydroxy, 3-phenylpropanoate by high-performance liquid chromatography and gas chromatography-mass spectrometry. In addition to these compounds, B. subtilis HJ927 also produced ${\beta}$-1,3-glucanase, a hydrolytic enzyme implicated in antifungal activity.

• Journal of Microbiology and Biotechnology
• /
• v.20 no.8
• /
• pp.1219-1225
• /
• 2010

Actinobacillus succinogenes, a representative succinicacid-producing microorganism, is seriously inhibited by ammonium ions, thereby hampering the industrial use of A. succinogenes with ammonium-ion-based materials as the pH controller. Therefore, this study isolated an ammonium-ion-tolerant mutant of A. succinogenes using a continuous-culture technique in which all the environmental factors, besides the stress (ammonium ions), were kept constant. Instead of operating the mutant-generating system as a nutrient-limited chemostat, it was used as a nutrient-unlimited system, allowing the cells to be continuously cultured at the maximum specific growth rate. The mutants were isolated on agar plates containing the acid-base indicator bromothymol blue and a high level of ammonium ions that would normally kill the parent strain by 100%. When cultured in anaerobic bottles with an ammonium ion concentration of 354 mmol/l, the mutant YZ0819 produced 40.21 g/l of succinic acid with a yield of 80.4%, whereas the parent strain NJ113 was unable to grow. When using $NH_4OH$ to buffer the culture pH in a 3.0 l stirredbioreactor, YZ0819 produced 35.15 g/l of succinic acid with a yield of 70.3%, which was 155% higher than that produced by NJ113. In addition, the morphology of YZ0819 changed in the fermentation broth, as the cells were aggregated from the beginning to the end of the fermentation. Therefore, these results indicate that YZ0819 can efficiently produce succinic acid when using $NH_4OH$ as the pH controller, and the formation of aggregates can be useful for transferring the cells from a cultivation medium for various industrial applications.