• 생태와환경
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• 제35권2호통권98호
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• pp.71-78
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• 2002

Seasonal change of total bacterial numbers were estimated in Daechung Reservoir from September, 1998 to August, 1999 and environmental factors which affects total bacterial numbers were estimated. Total bacterial numbers ranged between 1.2 and $19.0{\times}10^6\;cells/ml$ and averaged $6.9{\times}10^6\;cells/ml$. Bacterial numbers changed dynamically with season. The bacterial numbers were highest in July and showed peaks in April and July in sites studied except for the HOE (Hoenam site), In the HOE (Hoenam site), total bacterial numbers increased eve the period of March${\sim}$August. The correlation coefficient between bacterial number and chlorophyll a (<$200\;{\mu}m$) was r = 0.72(p< 0.05) at the MAN (man site). Total bacterial numbers in Daechung Reservoir was diversely changed by the seasonal variation of several environmental quality parameters.

• 미생물학회지
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• 제37권2호
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• pp.124-129
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• 2001

하수종말처리장의 처리효율에 미치는 염분의 영향을 알기 위하여 염분의 농도 변화에 따른 종속영양세균, 총세균 그리고 FISH 방법으로 세균 군집 구조를 파악하였다. 총세균수는 염분과 관계없이 큰 변화가 없었으나, 종속영양세균수와 군집구조는 염분에 따라 다르게 변화하였다. 염분이 1% 인 경우에는 대조구에 큰 변화가 없었으나, 염분이 2% 이상이 되면 종속영양세균과 Eubacteria의 비율이 줄어들고, 세균 군집도 큰 변화가 있었다. 특히 Proteobacteria $\alpha$-group, $\gamma$-group 및 Cytophaga-Flavobacterium group의 비율이 감소하였다. 염분이 증가하면, 종속영양세균수와 세균 군집이 변화하므로, 하수처리과정에서 염분이 유입될 경우에는 염분을 1% 이하로 유지하여야 한다.

• 자연과학논문집
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• 제16권1호
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• pp.143-154
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• 2005

대청호에서 세균군집의 생태학적 역할을 조사하기 위하여 대청호 본 댐과 대전 취수탑의 중간 지점인 대청호의 만입부 지점에서 1998년 9월~1999년 8월까지 DAPI 염색법으로 수심에 따른 총 세균수를 조사하였다. 조사지점의 수표면, 수심 5m, 10m, 15m, 및 25m에서 각각 채수하여 총 세균수를 측정하고 이화학적 수질요인과 총 엽록소 $\alpha$의 농도를 측정하였다. 총 세균수는 표층수에서 $1.6-1.7.0x10^6$ cells/ml, 수심 5m에서는 $2.3-11.0x10^6$ cells/ml, 수심 10m에서는 $1.2-1.4.0x10^6$ cells/ml, 수심 15m에서는$1.4-15.0x10^6$ cells/ml, 그리고 수심 25m에서는 $1.4-1.3.0x10^6$ cells/ml이었으며, 본 조사에서는 4월경부터 수온 증가에 따라 표층수의 총세균수는 증가하기 시작하여 7월경에 최대에 도달하였고, 이때 수심이 깊어질수록 총세균수는 감소하는 경향을 보였다. 각 수심에서 총세균수와 총엽록소 $\alpha$ 량 및 이화학적 수질요인과의 관계를 논의하였다.

• 한국물환경학회지
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• 제25권2호
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• pp.329-334
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• 2009

Bacterial numbers, such as endospore-formers, and treatment efficiencies were investigated for Rotating Activated Bacillus Contactors (RABC) and other advanced wastewater treatment processes including anaerobic-anoxic-oxic (A2O), sequencing batch reactor (SBR) and biological aerated filter (BAF). Endospore-forming bacterial numbers in the RABC showed 129-fold higher levels than those of the existing advanced systems. RABC process demonstrated the highest bacterial numbers in its bioreactors (paired t-test, p<0.01). RBC biofilms and aeration tanks of the RABC system showed 131- and 476-fold higher than other existing advanced processes, respectively. Mean treatment efficiencies of the existing systems were 83.5% for chemical oxygen demand (COD), 59.1% for total nitrogen (TN) and 76.8% for total phosphorus (TP). However, RABC process removed 96.9% for COD, 96.9% for TN and 91.9% for TP for highly concentrated food wastewater (COD>1,500 mg/L, TN>150 mg/L, TP>50 mg/L). Treatment efficiency was significantly reduced when the numbers of Bacillus genus in the bioreactors decreased below $10^6CFU/mL$. The automated RABC (A-RABC), in which dissolved oxygen concentrations are automatically controlled, showed higher treatment efficiencies compared to the RABC process. The RABC system maintained sufficient bacterial numbers for the effective treatment of highly concentrated food wastewater. Moreover, final effluent was in agreement to water quality standards.

• Asian-Australasian Journal of Animal Sciences
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• 제17권5호
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• pp.643-647
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• 2004

An in vitro experiment was carried out to investigate effects of solid associated (SAB) and liquid associated bacteria (LAB) and the type of incubation substrate on ruminal fermentation and gas production profiles. Bacterial fraction did not influence total numbers of bacteria. Gas production degradation parameters were significantly influenced by bacterial fraction and type of substrate (p<0.05). There was significant interaction between bacterial fraction and type of substrate in gas production (p<0.01). Total VFA concentration and acetic and propionic acid ratio were also influenced by bacterial fraction and type of substrate with little differences in individual VFA concentration.

• 미생물학회지
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• 제43권1호
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• pp.40-46
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• 2007

생태계가 파괴된 파로호에 수초대를 복원하는 방법으로 rubberized coconut fiber를 식생기반재로 사용한 인공식물섬을 2003년 8월에 설치하였다. 인공식물섬 식생기반재에서는 식물이 자랄 수 있을 정도로 영양염이 농축되어 꽂창포(Iris ensata), 노랑 꽃창포(Iris pseudoacorus), 갈대(Phragmites communis)등 식재된 식물이 잘 자랐다. 이 과정에서 세균의 역할을 알아보기 위하여 2004년 4월부터 10월까지 2주 간격으로 총세균수, 활성세균수, ${\beta}-glucosidase$, phosphatase를 조사한 결과 인공식물성 식생기반재의 공극수에서 각각 평균 $28.6{\times}10^{6}\;cells/ml,\;22.7{\times}10^{6}\;cells/ml,\;452.9nM/L/hr,\;16381.9nM/L/hr$로 조사되어 파로호 호수물보다 각각 10배, 15배, 22배, 38배 높았다. 그리고 영양염류농도는 총인과 충질소가 식생기반재 공극수에서 각각평균 1.06 mg/L, 12.5 mg/L으로 조사되어 호수물보다 12배, 3배 높았다. 이 결과 인공식물섬 식생기반재에서 새로운 생태계가 만들어졌으며, 이 생태계에서 세균이 중요한 역할을 하여 빈-중영양상태의 호수물에서도 식물이 잘 자랄 수 있었다.

• Journal of Microbiology
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• 제37권1호
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• pp.10-13
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• 1999

The bacterial abundance, proportion of respiring bacteria, and bacterial community of southern Lake Baikal were analyzed at 1 m and 400m depths during winter. The total bacterial numbers were 5.1${\times}$105 cells ml-1 at 1 m and 2.5${\times}$105 cells ml-1 at 400 m depth, which are about half and quarter of the numbers of other lakes. The proportion of respiring bacteria was as low as 2.5% at 1 m and 1.4% at 400 m depth. Considering the amount of organic carbon which need to be degraded and low proportion of respiring bacteria, the bacteria could be assumed to have high activities. The EUB/DAPI ratios were 77 and 89% at 1 m and 400 m depths, respectively. Of the bacterial community, the other group was dominant at both depths, and gamma group of protebacteria followed next. But the beta group of proteobacteria and Cytophaga-Flavobacterium groups occupied very small proportions.

• 한국환경과학회지
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• 제8권1호
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• pp.101-106
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• 1999

The relationship between primary productivity and changes in water quality was investigated at Mulgum station, a site downstream of the Nakdong River, Korea. Phytoplankton production was characterized by blooms of Microcystis aeruginosa during the summer and Stephanodiscus hantzschii during the winter. Primary production and secondary production by bacterioplankton ranged from 1.5~53.5 mg-C/ι day and 0.1~0.3 mg-C/ι day, respectively. Distribution of total organic carbon appeared to be highly correlated with phytoplankton biomass, especially during blooms of M. aeruginosa, when particulate organic carbon was 81% of total organic carbon and the main source of organic materials supplied into the water. The correlation coefficient between chlorophyll-a and BOD was 0.86. Thus it was concluded that autochthonous phytoplankton mostly affected the BOD level. Total bacterial numbers were also highly correlated with chlorophyll-a ($r^2$= 0.84) and the bacterial community appears to be regulated by phytoplankton biomass in this area.

• 한국식품영양학회지
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• 제20권4호
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• pp.363-368
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• 2007

Traditional kochujang samples were collected from the folk village in Sunchang to find the major microbial composition and correlation between the taste and the microbial properties. Among the 29 samples, 17 samples showed Bacillus licheniformis as dominant strain with 11 samples Bacillus subtilis and 1 sample Staphylococcus pasteuri. Subdominant strain of 17 samples was Bacillus licheniformis with 12 samples Bacillus subtilis. Dominant strain numbers varied in rage of $6.60{\sim}8.38$ logCFU/g with subdominant strain number $5.90{\sim}7.86$ logCFU/g and total microbial number $6.64{\sim}8.56$ logCFU/g respectively. Bacterial type number varied in range of $6{\sim}18$ with the average 10.5 types. Fungi were found only in 2 samples and identified all to be Aspergillus oryzae. Yeasts were found in 25 samples. The dominant yeast strain of 23 samples was identified to be Zygosaccharomyces pseudorouxii and that of 2 samples Zygosaccharomyces rouxii. Yeast type variety showed that only single type was found in 15 samples, 2 types in 8 samples, 3 types in 1 sample and 4 types in 1 sample. Fungal number was 3.90 and 4.08 logCFU/g and yeast numbers varied in range of $3.90{\sim}6.43$ logCFU/g. The sensory scores of kochujang showed positive correlation with type numbers, but no significant correlation with the other microbial properties like total bacterial number, dominant bacterial number, subdominant bacterial number and dominant yeast number.

• Applied Biological Chemistry
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• 제21권2호
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• pp.81-83
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• 1978

밭 토양에 bentazon을 50, 200ppm 처리(處理)하여 $NH_4-N$의 질산화(窒酸化) 작용(作用) 및 아질산산화(亞窒酸酸化) 세균수(細菌數), 그리고 총세균(總細菌) 및 사상균수(絲狀菌數)의 변동(變動)에 미치는 영향을 조사해 본 결과는 다음과 같다. 1. 처리 농도가 높을 수록 질산화 작용은 지연되었으며 아질산(亞窒酸) 산화균수(酸化菌數)도 현격한 감소를 나타냈다. 2. 총균수(總菌數) 및 사상균수(絲狀菌數)의 변동(變動)은 농도(濃度)가 높아짐에 따라 세균수(細菌數)는 감소하였으나 사상균수(絲狀菌數)는 초기에는 반대로 증가하는 경향이 었다.