• Proceedings of the Korean Society of Organic Agriculture Conference
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• 2009.12a
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• pp.302-302
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• 2009

유기농업에서 유기물은 양분의 공급, 토양의 이화학성 개선, 토양의 생물학적 건전성 유지 등 중요한 역할을 한다. 토양의 생물학적 건전성은 토양의 생태계적 기능을 지속적으로 유지시키는 토양미생물이 관여하고 있다. 따라서 본 연구는 유기물의 장기연용에 따른 밭토양 미생물의 다양성을 비교 분석하였다. 여러 가지 유기자원을 동일한 기준으로 매년 동일 장소에 처리하였다. 사용된 유기자원은 가축분퇴비, 채종유박인 유기질비료, 볏짚으로만 퇴비화한 볏짚퇴비와 겨울철 휴한기에 헤어리베치를 재배하여 이듬해 봄에 예취한 후 토양에 환원한 녹비처리구, NPK구, 가축분퇴비를 혼용처리한 NPK퇴비군, 양분을 전혀 시용하지 않은 무비구 등 총 7처리구였다. 각각의 처리구에서 토양(0-20 cm)을 채취하여 배양성 토양미생물은 희석평판법으로 해당 선백배지에 시료를 도말 하여 조사하였고 비배양성 미생물은 토양으로부터 genomic DNA를 추출하여 세균의 16S rDNA를 증폭시킨 후 denaturing gradient gel electrophoresis (DGGE)를 수행하여 분석하였다. 주요결과를 요약하면 밭토양에 서식하는 토양미생물의 균수는 처리별간의 차이를 보였으며 유기물처리구가 화학비료처리구보다 높았다. DGGE 분석을 통해 유기물 처리에 따른 군집의 다양성을 살펴본 결과 Fig. 1에서 보는바와 같이 Gel 상에서 다양한 위치의 밴드를 확인할 수 있었고 처리별로 특이 밴드가 있음을 확인할 수 있었다. Fig. 1에서 얻은 DGGE profile상의 밴드 강도와 수를 비교하여 Fig 2와 같은 dendrogram을 나타낼 수 있었다.

• Journal of fish pathology
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• v.26 no.3
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• pp.193-206
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• 2013

The ark shell, Scapharca broughtonii is a marine bivalve mollusks belonging to the family Arcidae and important seafood for Korean and Japanese, and southern coast is brisk bays for the ark shell aquaculture. However, productivity of ark shell from these regions were rapidly reduced during the last decade due to mass mortality. The reason of this great damage has not yet been identified. To overcome this economic loss, diverse investigations were focused on environmental factors that affects in the physiology of S. broughtonii, but microbiological researches were performed insufficiently. Hemoglobin is one of the major blood component of ark shell and is damaged by some species of bacterial toxins. We concentrated on this red pigment because hemolysis could be the cause of ark shell mortality. In this study, we analyzed microbial diversity of underwater sediments in coastal regions and also existences in the body of S. broughtonii. We investigate about 4,200 isolates collected from June to September for microbial diversity of sediments and ark shell. We screened all of culturable microorganisms, and identified 25 genera 118 species, 24 genera 89 species, 30 genera 109 species and 39 genera 141 species, and selected 140 unique colonies for identification and challenge assay.

• KSBB Journal
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• v.16 no.3
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• pp.225-232
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• 2001

The hydrophobicity of the microbial cell surface is responsible for the various interactions between microorganisms and different surface, and results in the flocculation of microbial cells, their adhesion to liquid or solid materials, and the floatation of microorganisms at the air-water interface. Accordingly, cell surface hydrophobicity is important not only in medicine but in other areas of biotechnology. This article reviews the role of cell surface hydrophobicity and its applications.

• Korean Journal of Soil Science and Fertilizer
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• v.30 no.2
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• pp.200-207
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• 1997

In order to evaluate the soil microbiological characteristics of paddy fields in Korea, surface soils were sampled from 63 sites in different agroclimatic zones before submersion of the fields. The distribution of microorganisms and the microbial diversity indices were examined. Soil microbial populations were generally higher in southern area than in northern area. The colony forming units(cfus) of fluorescence Pseudomonas sp. showed the greatest regional differences, among the microbes investigated. On the topographical differences, the cfus of aerobic bacteria, fluorescence Pseudomonas sp. and Azotobacter sp. maintained high level in coastal plains; and on the sail textural difference, fungus was the highest in clay soil, but Bacillus sp., Azotobacter sp and denitrifiers were the highest in silty clay loam soil at 0.05 probability level based on the multiple range test. The numbers of ammonium oxidizers and Azotobacter sp. were increased with soil pH. Microbial diversity indices of paddy fields which calculated from the percentages of Bacillus sp. fluorescence Pseudomonas sp. Azotobacter sp. denitrifiers, ammonium oxidizers, nitrite oxidizers, actinomycetes and fungus to these total microbial numbers were between 0.109 and 0.661. On the soil textures, the microbial diversity indices of sandy, sandy loam, silty clay loam, clay loam and clay soil were 0.443, 0.427, 0.414, 0.405 and 0.362 respectively.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.36 no.5
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• pp.839-846
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• 2016

Since oil leakage is one of the most common nonpoint pollution sources that contaminate soil in Korea, the capacity of soil microbial community for degrading petroleum hydrocarbons should be considered to assess the functional value of soil resource. However, conventional methods (e.g., microcosm experiments) to assess the remediation capacity of soil microbial community are costly and time-consuming to cover large area. The present study suggests a new approach to assess the toluene remediation capacity of soil microbial community using a microbial diversity index, which is a simpler detection method than measuring degradation rate. The results showed that Shannon index of microbial community were correlated with specific degradation rate ($V_{max}$), a degradation factor. Subsequently, a correlation equation was generated and applied to Michaelis-Menten kinetics. These results will be useful to conveniently assess the remediation capacity of soil microbial community and can be widely applied to diverse engineering fields including environment-friendly construction engineering fields.

• Microbiology and Biotechnology Letters
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• v.21 no.1
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• pp.88-94
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• 1993

Actinomycetes are the most diverse group of bacteria. in variety. morphology. and life cycle. Especially. the variety of genus and species of Actinomycetes is so diverse among other microorganisms that about 50 genus of Actinomycetes have been reported until now. Among them. Streptomyces genus is the most plentiful and over 220 species have been reported. The number of the genus of Actinomycetes will be expected to be fixed to about 55 genus and 250 Streptomyces species in the year 2000 thereabouts. Morphological and physiological characters of Actinomycetes varies with culture condition. and therefore diverse life cycles are also possible. In this paper. life cycles of the representative Actinomycetes, Nocardia, Streptomyces. Kitasatosporia. GeodermatoPhi/us. and Sporichthya. according to the condition of nutrient in the media were reviewed.

• Korean Journal of Environmental Biology
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• v.17 no.3
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• pp.279-284
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• 1999

To investigate soil bacterial diversity according to vegetation types, directly extracted DNA from 5 different soils were cross-hybridized with each other as a probe and target. Pinus densiflora soil was shown the highest value then agricultured soil＞naked soil＞grass soil＞Quercus mongolicas soil in the order of diversity. Cluster analysis by similarity showed that soil microbial communities were categorized into three groups.

• Food preservation and processing industry
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• v.7 no.2
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• pp.2-2
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• 2008

발효는 인류의 역사와 함께 해 왔으며 과학 기술발전에 따라 자연 발효에서 관리하는 방법으로 급격히 변하고 있다. 발효는 미생물과 미생물이 생산한 효소의 작용으로 일어나는바 미생물 관리를 통하여 실로 다양한 제품 생산이 가능하고 역할의 범위도 지극히 넓다. 즉 원하는 최종 제품의 종류에 따라 미생물을 선택하거나 발효조건을 관리하여 목적 지향적 완제품 생산이 가능한 경우가 많다. 한국인의 식단을 이루는 기본은 각종 발효 제품을 근간으로 하는 조미료이며, 조미료에 따라 맛의 변화가 온다. 발효를 통하여 소화성의 증대, 비타민 등 새로운 미량물질의 생산, 풍미의 개선 혹은 새롭게 창조하거나 저장기간을 연장하기도 하며, 사용하는 원료와는 완전히 다른 신제품을 만들어 내기도 한다. 근래의 연구 결과들을 살펴보면 여러 기능성 물질이 발효를 통하여 생성되며 이들이 인체 내에서 긍정적 역활을 한다는 것이 밝혀지고 있다. 전통식품 중 발효식품은 가장 큰 비중을 차지하며 곡류 중심의 식단에 맛을 부여하여 먹는 즐거움을 주고 전망있는 다른 산업으로 발전 해 나갈 수 있는 특성이 있다. 발효식품은 다양한 원료를 사용 할 수 있고 원료에 따라 많은 서로 다른 제품생산이 가능하다. 우리나라에서 생산되는 주요 발효식품은 김치를 포함한 절임류, 곡물 또는 과실을 이용한 주류, 어류로 각종 젓갈을 만들 수 있으며 근래 수요가 늘고 있는 요구르트 등도 인기 있는 발효식품이다. 특히 발효식품에 관여하는 미생물들이 probiotic으로 작용하여 장내 미생물의 항산성 유지 및 유해 세균의 증식억제 등 긍정적 역할을 하며 우유 발효균으로 알려진 젖산균류 뿐만 아니라 다른 세균들도 probiotic으로 작용한다는 것이 밝혀지고 있으며, 특히 장류에 많이 관여하는 Bacillus 속 들의 긍정적 역할이 속속 알려지고 있다. 또한 발효를 통하여prebiotic도 만들어지는 것을 알 수 있다. 앞으로 발효식품의 기능성의 과학적 입증 발효의 과학적 관리, 제품의 다양화와 함께 안전성도 검토할 대상이다. 또한 심도있게 발효 관여 미생물을 탐색, 동동하고 발효기반의 이용확대, 맞춤형 특수 미생물의 탐색과 용도 확인 등 노력이 필요하다. 우리나라 전통식품 중 큰 비중을 차지하는 발효식품을 세계화하기 위해서는 건강기능성의 과학적 기반 구축과 전문 학술 활동을 통한 홍보, 현지 식품에 맞는 fusion food의 개발도 필요하다. 발효식품을 포함한 전통식품은 경제적 측면과 함께 문화적 가치가 동시에 고려되어야 하고 다문화 추세에 따라 유연성 있게 변화를 수용 할 필요도 있다. 전통 발효식품을 우리 식문화를 세계에 전파시키는 좋은 매체로 활용 할 수 있을 것이다.

• Korean Journal of Environmental Agriculture
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• v.27 no.3
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• pp.260-266
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• 2008

The aim of present work was to assess the response of soil microbial activity and diversity to green manures under the organically managed grape-greenhouse in early spring. Hairy vetch, milk vetch, and red clover were seeded in fall, and enzymatic activities by dehydrogenase and fluorescein diacetate (FDA) hydrolase, and microbial diversities by Biolog $EcoPlate^{TM}$ and phospholipid fatty acid (PLFA) were characterized for soils sampled in early spring. Dehydrogenase activity and FDA hydrolytic activity did not differentiate the green manures but the average well color development of Biolog EcoPlate was higher in soils covered with red clover than control soil. Soil microbial functional diversity by Biolog EcoPlate differentiated the soils covered with hairy vetch and milk vetch, and Shannon diversity index by Biolog EcoPlate was higher in soils covered with hairy vetch than control soil. Principal component analysis of PLFA differentiated the soils covered with milk vetch from control soil.

• Korean Journal of Environmental Agriculture
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• v.30 no.4
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• pp.367-376
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• 2011

BACKGROUND: In order to develop effective assessment method for Korean paddy soil microbial community structure, reliable genomic DNA extraction method from paddy soil and quantitative real-time PCR (qRT-PCR) method are needed to establish METHODS AND RESULTS: Out of six conventional soil genomic DNA extraction methods, anion exchange resin purification method was turn to be the most reliable. Various PCR primers for distinguishing five bacterial phylum (${\alpha}$-Proteobacteria, ${\beta}$-Proteobacteria, Actinobacteria, Bacteroidetes, Firmicutes), all bacteria, and all fungi were tested. Various qRT-PCR temperature conditions were also tested by repeating experiment. Finally, both genomic DNA extraction and qRT-PCR methods for paddy soil were well established. CONCLUSION: Quantitative real-time PCR (qRT-PCR) method to assess paddy soil microbial community was established.