• Journal of environmental and Sanitary engineering
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• v.20 no.4 s.58
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• pp.21-30
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• 2005

This research was performed to measure the concentration distribution of bioaerosol in apartment houses in the region of Chungnam (Chunan, Asan) for 1 month, December, 2004. The results are as follows. 1. By using SDA method, the average concentration of total microbe and fungus in the air inside and outside apartment house below 4 years are $69,42cfu/m^3\;and\;15.66cfu/m^3$, while apartment house over 4 years, $214.58cfu/m^3\;and\;216.43cfu/m^3$, respectively With gravitational sedimentation method, the average concentration of total microbe and fungus of apartmenthouse below 4 years are $100.63cfu/m^3\;and\;22.83cfu/m^3$, while apartment house over 4 years, $216.43cfu/m^3\;and\;70.000cfu/m^3$, respectively. 2. The I/O ratio of floating germ of apartment house below 4 years and over 4 years are 2.87 and 5.12 for total microbe, and 3.32 and 8.28 for fungus, respectively. The I/O ratio of falling germ of apartment house below 4 years and over 4 years are 1.55 and 2.81 for total microbe, and 2.85 and 4.08 for fungus, respectively. The apartment house below 4 years shows a low I/O ratio in all cases. 3. The difference in concentration of microbe between inside master bedroom and living room of apartment house below 4 years is $13.183cfu/m^3$, total microbe, and $4.787cfu/m^3$, fungus, while, apartment house over 4 years, $43.531cfu/m^3$, total microbe, and $21.932cfu/m^3$, fungus. The measured differences are statistically significant. 4. Air sampler was used to verify the difference in concentration of microbe with the age of apartment house. The difference in concentration of total microbe and fungus for outside apartment house below 4 years and over 4 years are $49.82cfu/m^3$ and $3.78cfu/m^3$, respectively. The difference of inside living room shows $160.23cfu/m^3$ for total microbe and $28.01cfu/m^3$ for fungus, and the difference of inside master bedroom shows $225.43cfu/m^3$ for total microbe and $56.73cfu/m^3$ for fungus. The differences are statistically significant. The difference in concentration of outside apartment house below 4 years and years 4 years are $34.66cfu/m^3$, total microbe, and $15.66cfu/m^3$, fungus, while inside apartment house below 4 years and over 4 years, $196.93cfu/m^3,\;and\;78.67cfu/m^3$, respectively. The measured differences are statistically significant.

• Journal of Environmental Science International
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• v.10 no.5
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• pp.315-321
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• 2001

This study was conducted to estimate the decomposition capacity for organic matter by microbe of tidal flat sediments (Hajae, Dongjin and Mankyung). The decomposition rate constants (K') have been determined by Thomas slope method and compared with the values of each tidal flats. The decomposition rates of organic matter by microbe were initially very slow, but at the end of 12 hours, very sharply increased. The values of decomposition rate constant for Dongjin, Mankyung and Hajae tidal flat sediment were 1.364$day^{-1}$/, 1.080d$day^{-1}$ and 0.735$day^{-1}$, respectively. The decomposition rate constant of Dongjin tidal flat sediment which affected by livestock wastewater was higher than others. The decomposition quantity (mg/g/day) of organic matter by microbe of tidal flat sediments was 0.4mg/g/day for Dongjin, 0.36mg/g/day for Mankyung and 0.36mg/g/day for Hajae. The average of decomposition quantity was 0.37mg/g/day. To calculate purification capacity (kg/ha) of organic matter by microbe, we applied to two assumption ; 1) biological action by microbe is occur within 0.1cm under surface 2) specific gravity of sediment are 2.5g/$\textrm{cm}^2$. The purification capacity of organic matter by microbe of tidal flat sediment was calculated to 9.25kg/ha. The relationships between decomposition rate constant (K') and ignition loss (I. L), chemical oxygen demand by sediment (CO $D_{sed}$), total carbon(TC), silt and clay as index of organic matter were a high positive($R^2$=0.97~1.00).

• Journal of Food Hygiene and Safety
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• v.27 no.1
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• pp.87-95
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• 2012

This study was investigated to determine the contamination levels of total aerobic bacteria, coliform group, $E.$ $coli$ and food-borne pathogens of side dishes from 2 traditional markets (100 samples) and 2 super markets (100 samples) located on Ulsan. The levels (range) of total aerobic bacteria was 4.75 log CFU/g (1.60~6.92 log CFU/g) in traditional market and 4.62 log CFU/g (2.00~6.46 log CFU/g) in super market, respectively. Coliform was detected in 64 and 66 samples sold at traditional markets and super markets, respectively. $E.$ $coli$ was detected in 4 and 6 samples sold at traditional markets and super markets, respectively. The food-borne pathogens, namely $Bacillus$ $cereus$ and $Listeria$ $monocytogenes$ were detected in 1 sample sold at traditional markets, respectively, and $Bacillus$ $cereus$ was detected in 4 samples sold at super markets. However, other pathogens such as $Salmonella$ spp., $Shigella$ spp., $Vibrio$ $parahaemolyticus$, $Yersinia$ $enterocolitica$, $Clostridium$ $perfringens$, $Camphylobacter$ $jejuni$ and Pathogenic $E.$ $coli$ were not detected. The $Saengchae$ and $Seasoned$ $Jeotgal$ were relatively vulnerable compared to the others in the food-borne pathogens.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.6
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• pp.1126-1135
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• 2012

In order to produce high-quality fermenting composts, bacteria strains with high activities of extracellular enzymes (cellulase, chitinase, amylase, protease and lipase) were isolated from the soils in 6 provinces of Korea, and characterized by 16S rRNA gene sequence analysis and properties. The selected 7 stains inoculated to livestock manure for 2' fermenting time, and experimental treatment divided into 3 groups, B1, B2 and B3, according to microbial activity and enzyme type. Our results showed that microbe applications (B1, B2 and B3) can increase (p<0.05) both rhizomes (17-38%) and enzyme activities (50-81%) in compost after fermenting time, respectively, compared to non-microbe treatment (control). The microbe application also decreased significantly (p<0.05) the $NH_3$ and $H_2S$ gas contents 13.4 and 27.3% compared with control, and the Propionic acid and Butyric acid gas contents 14.5 and 19.6%, respectively, as compared to the control. The microbial degradation rate (%) of pesticides and heavy metals increased significantly (p<0.05) after fermenting time, respectively, as compared to the control. Especially, microbe applications were more effective in total rhizomes yields and bioactivities than non-microbe treatment. Thus the results of this study could help in development of potential bioinoculants and composting techniques that maybe suitable for crop production, and protectable for earth environment under various conditions.

• Journal of Korean Society of Water and Wastewater
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• v.18 no.4
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• pp.470-479
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• 2004

The experimental conditions and relationships between parameters such as organic matter, aeration volume, aeration time, and precipitation time for the effective treatment of domestic wastewater were investigated. With the batch systems, the adsorption amount of unit microbe was measured with the change of MLSS concentration, precipitation time, and aeration amount. Theoretical adsorption amount of microbes was then numerically formulated by use of a SPSS multiple analysis as follows: $$Y=-0.0106(X_1)+0.07310(X_2)+42.705(X_3)+62.700$$ In this study, the amount of organisms to be removed in the range of MLSS concentration 2,000~4,500 mg/l were examined. In order to investigate the optimal condition of nitrification, the upper water in the biosorption stage was used as the initial experiment water. The results showed that the C/N ratio was 1.5 and the reaction time for the optimal nitrification was 1.5 hr. When the adsorption efficiency for microbe biosorption was 66%, the optimum denitrification efficiency was 83.3%. When the optimum parameters obtained from the batch experiment were applied to the lab-scale operation, the total retention time from the flow-in to flow-out was 10 hours and the removal efficiency was 93.8% for $COD_{cr}$ and 80.9% for TN. For the full-scale operation, the total retention time was 9.0 hours and the removal efficiency was 94.4% for BOD, 89.6% for $COD_{cr}$, 88.0% for TN, and 86.2% for TP.

• Journal of Environmental Health Sciences
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• v.28 no.3
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• pp.34-38
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• 2002

Statistical analysis between sewage plant operating parameters and the effluent quality was performed. We extracted two factors from principal component analysis of operating parameters and effluent quality from each plant. The total variance of 84.7%, 79.2% was explained by the two factors at SB plant and SC plant, respectively. The factors were identified at SB plant in the following order 1) the oxidation of organic material by aeration basin microbe,2) biomass in aeration basin and at SC plant 1) the oxidation of organic material by aeration basin microbe, 2) thickening of acti-vated sludge. These results suggested that the control of microbial composition might be critical on the improvement of the effluent quality and plant operating efficiency because most of the factors were related with microbes.

• Food Science and Preservation
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• v.6 no.3
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• pp.339-344
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• 1999

The effects of water extracts of cow bone(WECB), and crab-shell powders(CSP) on the fermentation of kimchi were investigated. WECB has not a great effects on pH, titratable acidity, ratio of lactic acid bacteria against total microbe, and the number of Leuconostoc and Lactobacilli, but has on sour taste, and flavor and overall taste. The kimchi prepared by adding the 0.03% WECB and 1.5% CSP together showed more effective than the control and CSP-added kimchi in pH maintenance, buffer action ratio of lactic acid bacteria against total microbe. The sensory profiles such as fishy and garlic flavor, crispness and overall taste showed in the control and CSP-added kimchi were improved in the kimchi added no only, and CSP and WECB together.

• Journal of Microbiology and Biotechnology
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• v.21 no.11
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• pp.1184-1192
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• 2011

A bacterial isolate (strain JS-2) characterized as Bacillus sp. was challenged with high concentrations of toxic selenite ions. The microbe was found to transform the toxic, soluble, colorless selenite (${SeO_3}^{2-}$) oxyions to nontoxic, insoluble, red elemental selenium ($Se^0$). This process of biotransformation was accompanied by cytoplasmic and surface accumulation of electron dense selenium ($Se^0$) granules, as revealed in electron micrographs. The cells grown in the presence of selenite oxyions secreted large quantities of extracellular polymeric substances (EPS). There were quantitative and qualitative differences in the cell wall fatty acids of the culture grown in the presence of selenite ions. The relative percentage of total saturated fatty acid and cyclic fatty acid increased significantly, whereas the amount of total unsaturated fatty acids decreased when the cells were exposed to selenite stress. All these physiological adaptive responses evidently indicate a potentially important role of cell wall fatty acids and extracellular polymeric substances in determining bacterial adaptation towards selenite-induced toxicity, which thereby explains the remarkable competitiveness and ability of this microbe to survive the environmental stress.

• Journal of Soil and Groundwater Environment
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• v.21 no.1
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• pp.94-103
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• 2016

Landfarming that supplies aerobic biodegradation condition to indigenous microbes in soils is a biological remediation technology. In this research, volatilization and biodegradation rate by indigenous microbes in the soil contaminated with total petroleum hydrocarbons (TPH) were measured. Soils were contaminated with diesel artificially and divided into two parts. One was sterilized by autoclave to remove indigenous microorganism and the other was used as it was. Various moisture contents and number of tillings were applied to the soil to find out proper condition to minimize volatilization and enhance bioremediation. Volatilization of TPH was inhibited and biodegradation was enhanced by increase on moisture content. Tilling was usually used to supply air for microbes, but tillings did not affect the growth of microbes in our study. Enough moisture content and proper aeration are important to control volatilization in landfarming. Also, TPH degradation was a function of the microbe counts (x₁), numbers of tilling (x₂), and moisture content (x₃) from the application of the response surface methodology. Statistical results showed the order of significance of the independent variables to be microbe counts > numbers of tilling > moisture content.

• Food Science and Preservation
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• v.13 no.4
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• pp.445-449
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• 2006

This study was carried out to investigate the quality properties of pomegranate concentrate with different sterilization conditions and storage temperature during storage. Total microbe level detected in non-sterilization pomegranate concentrate and the multiplication rate of total microbe level were higher at a storage temperature of $37^{\circ}C$ than at $10^{\circ}C$. Coliform was not detected in any of the samples. The pH was gradually increased but $^{\circ}Brix$ and total acidity were gradually decreased. Changes in a color values were gradually decreased but that of the sterilized pomegranate concentrate at $65^{\circ}C$(30 min) wasn't changed after storage at $10^{\circ}C$. The sterilization of pomegranate concentrate at $65^{\circ}C$ (30 min) could be useful for preservation.