• 환경위생공학
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• 제20권4호통권58호
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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.

• 한국환경과학회지
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• 제10권5호
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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).

• 한국식품위생안전성학회지
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• 제27권1호
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• pp.87-95
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• 2012

본 연구에서는 울산지역의 재래시장 및 대형할인점에서 판매되는 즉석 반찬류의 미생물학적 안전성을 평가하여 이들 반찬류의 위생상의 문제점을 파악하고 이를 개선하기 위한 기초자료로 삼고자 재래시장(2곳), 대형할인점(2곳) 총 4곳에서 구입한 반찬류 4종 20품목 200건에 대해 위생지표세균인 일반세균, 대장균군, 대장균과 식중독 원인균인 $Salmonella$ spp., $Shigella$ spp., $Staphylococcus$ $aureus$, $Listeria$ $monocytogenes$, $Vibrio$ $parahaemolyticus$, $Yersinia$ $enterocolitica$, $Bacillus$ $cereus$, $Clostridium$ $perfringens$, $Camphylobacter$ $jejuni$, Pathogenic $E.$ $coli$를 조사하였다. 일반세균의 평균 검출량 (범위)는 재래시장이 4.75 log CFU/g (1.60~6.92 log CFU/g), 대형할인점이 4.62 log CFU/g(2.00~6.46 log CFU/g) 수준으로 구입 장소에 따른 유의적인 차이는 없었다. 대장균군의 검출건수(검출률)는 재래시장이 총 64건(64%) 으로, 젓갈류와 절임류가 각각 20건(80%), 조림류 13건(52%), 생채류 11건(44%)의 순을 나타내었다. 대형할인점은 66건(66%)이 검출되었고, 젓갈류와 조림류 19건(76%), 절임류 18건(72%), 생채류 10건(40%)의 순을 보여 재래시장과 마찬가지로 생채류가 낮은 검출을 나타내었다. 그리고 평균 검출량은 재래시장과 대형할인점 모두 생채류가 대체적으로 낮은 경향을 보였다. 대장균은 재래시장에서 오징어젓갈 (젓갈류) 1건, 된장콩잎 (절임류) 2건, 깻잎장아찌 (절임류) 1건 등 4건(4%)에서 검출되었고, 생채류와 조림류에서는 검출되지 않았다. 그리고 대형할인점은 생마늘쫑 (생채류) 1건, 고들빼기 (절임류) 1건, 된장콩잎 (절임류) 2건, 깻잎장아찌 (절임류) 2건 등 6건(6%)에서 검출되었고, 젓갈류와 조림류에서는 검출되지 않았다. 식중독균 검사결과, $B.$ $cereus$와 $L.$ $monocytogenes$는 재래시장에서 각각 1건(생채류 1건, 젓갈류 1건)이, $B.$ $cereus$는 대형할인점에서 4건(생채류 1건, 절임류 1건, 조림류 2건)이 확인되었으며 $Salmonella$ spp., $Shigella$ spp., $Vibrio$ $parahaemolyticus$, $Y.$ $enterocolitica$, Pathogenic $E.$ $coli$, $C.$ $jejuni$ 등 나머지 식중독균은 검출되지 않았다. 결론적으로 반찬류의 안전성은 위생지표세균 측면에서는 절임류, 젓갈류, 조림류가 (특히 절임류), 식중독균 측면에서는 생채류와 젓갈류가, 그리고 대형할인점이 재래시장에 비해 상대적으로 취약하여 이에 대한 위생관리가 필요하다고 판단된다. 따라서 시판 반찬류의 미생물적 안전성 확보를 위해 제조단계, 유통단계, 판매단계에 이르기까지 안전을 위한 총체적인 관리방안의 수립과 체계적인 관리가 요구된다.

• 한국토양비료학회지
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• 제45권6호
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• pp.1126-1135
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• 2012

다양한 기능을 가진 토착미생물을 분리 동정 후 퇴비화에 적용하여 우수한 기능성을 가진 발효퇴비를 제조하고자 하였다. 7개의 우수 토착미생물을 주축으로 3개의 발효퇴비를 제조하여 생리활성을 조사한 결과, 대두의 발아율 증가, 섬유소, 키틴, 단백질 분해 등의 생리활성이 대조구보다 뛰어나고, 오옥신 생산량이 유의적으로 증가하였다. 퇴비중 암모니아 가스와 휘발성 지방산 함량 역시 2차 발효가 시작되는 20일까지 함량 감소가 있었고, 대두의 건물수량이 증가함을 확인하였다. 또한 식물보호제 분해시험에서도 유의적인 분해율이 있었고, 중금속 함량 역시 유의적으로 감소하였다. 따라서 토착미생물의 다 기능적 활성을 활용한 발효퇴비의 제조는 기존보다 더 향상된 발효퇴비를 농업생산 환경에 적용할 수 있을 것이다.

• 상하수도학회지
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• 제18권4호
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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.

• 한국환경보건학회지
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• 제28권3호
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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.

• 한국식품저장유통학회지
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• 제6권3호
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• pp.339-344
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• 1999

김치의 향미개선 및 게껍질 분말 첨가김치의 부미를 제거하기 위한 향미개선제로서 우골추출물의 첨가효과를 검토하였다 우골추출물은 김치의 숙성중 pH와 산도, 총균수, 젖산균비, Leuconostoc과 Lactobacilli의 수에는 큰 영향을 미치지 못하였으나 산미와 김치냄새를 감소시키고 종합적 맛을 개선시키는 향미 개선제로서의 역할을 하였다. 또 우골추출물(0.03%)을 게껍질분말(1.5%)과 함께 첨가할 경우는 게껍질분말만을 첨가한 경우보다 높은 pH를 유지하는 한편 완충효과가 증가되었으며 젖산균비가 높아졌다. 관능검사에 의하여 평가한 결과 게껄질분말을 단독으로 첨가한 경우보다 우골추출물을 병용하여 첨가한 김치에서 비린 맛이 낮아졌으며, 아삭아삭한 맛과 종합적인 맛은 숙성전반에 걸쳐 높게 나타났다.

• Journal of Microbiology and Biotechnology
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• 제21권11호
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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.

• 한국지하수토양환경학회지:지하수토양환경
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• 제21권1호
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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.

• 한국식품저장유통학회지
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• 제13권4호
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• pp.445-449
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• 2006

본 연구에서는 살균조건 및 저장온도에 따른 석류농축액의 품질특성을 조사하였다. 대장균은 모든 구간에서 검출되지 않았으나 일반미생물은 살균처리 하지 않은 구에서 조금 검출되었으며 $10^{\circ}C$보다 $37^{\circ}C$에서 저장할 때 더 많이 증식하였다. 저장 중 pH는 조금씩 증가하는 경향이며 총산은 조금 감소하는 경향으로 구간들 간에 큰 차이는 없었다. 당도는 저장 중 조금 감소하는 경향으로 나타났다. $37^{\circ}C$에서 저장할 때 L, a b값 모두 점점 감소하는 경향을 나타내었으나 $10^{\circ}C$에서 (B)구간의 경우 색도에 큰 변화가 없어 석류 농축액을 $65^{\circ}C$에서 30분간 살균한 후 $10^{\circ}C$에서 저장하면 미생물의 오염을 방지하고 색의 변화를 최소화 할 수 있는 것으로 나타났다.