• 한국토양비료학회지
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• 제43권3호
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• pp.384-389
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• 2010

Outbreak of contagious diseases to livestock animals is becoming prevalent worldwide and consequently, tremendous numbers of the infected or culled stocks are buried on the ground as the most common disposal method. The buried animals can generate a wide range of detrimental components such as leachate, nutrient salts, and pathogenic bacteria, consequently contaminating the surround environment. This implies that regular investigations are required to monitor any possible detrimental environmental aspect occurred around burial sites. Therefore, the current study was conducted to investigate whether the soil and groundwater nearby the burial sites had been contaminated by the substances originated from the burial sites, which can be applied for the establishment of the ideal burial site construction design and post management scheme. For this, two different burial sites located in Cheonan and Pyeongtaek were selected. Cheonan and Pyeongtaek sites were constructed in 2004 and 2008, respectively and both contained dead poultry infected by avian influenza (AI). Soil and groundwater samples were collected around the sites followed by determination of the nutrient concentrations and bacteria (Salmonella, Camphylobacter, and Bacillus) existence in both soil and groundwater. Some of the soil samples showed higher EC, $NH_4$-N, $NO_3$-N concentration compared to those of the background (control) soils. Also the concentration of $NH_4$-N in some of the groundwater samples appeared to exceed the USEPA guideline value for drinking water (10 mg $L^{-1}$). These results indicated that the soil and groundwater were influenced by the burial site originated nutrients. In the soil, Bacillus was isolated in most soil samples while there were no detections of Salmonella and Camplylobacter. Due to the Bacillus existing mainly as a spore in the soils, it was considered that the frequent detection of Bacillus in the soil samples was attributed to the nutrients originated from the burial sites.

• 한국토양비료학회지
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• 제41권6호
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• pp.415-418
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• 2008

폐기물 연용토양의 미생물 군집 분석을 위해 공단지역 하수 슬러지 처리등 16처리(3수준)에 대하여 가장 좋은 방법을 찾고자, RFLP, CLSU, PLFA, TGGE 의 4가지 방법을 이용하였으며, 이들 4가지 방법에 대하여 시기별 군집변동 조사를 통한 통계적 비교 분석을 하였다. 그 결과, 미생물의 경시적 군집 변동상 관찰은 PLFAs (Phospholipid Fatty Acids) 방법이 가장 효율적이었으며 RFLP는 많은 종류의 제한 효소의 사용이 필요하다. TGGE는 DNA 추출을 통해 비배양학적인 분석에서는 가장 좋은 방법이나 PCR조건 등 실험 과정에서 토양종류에 따라 민감하게 반응하여 비슷한 조성의 토양분석에 효율적이라고 생각한다.

• 농약과학회지
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• 제21권1호
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• pp.1-8
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• 2017

유기염소계 살충제 엔도설판은 2012년 국제적으로 사용이 금지되었으나 인도와 중국을 비롯한 국가들에서 여전히 사용되고 있으며 높은 잔류성과 이동성으로 인해 다양한 환경에서 검출되고 있다. 본 연구에서는 엔도설판이 토양세균의 군집구조에 미치는 영향을 16S rRNA 유전자 파이로시퀀싱 기법을 이용하여 분석하였다. 엔도설판을 100 mg/kg의 수준으로 밭토양에 처리했을 때 세균의 Operational taxonomic unit (OTU) 수와 다양성 지수가 감소했다가 서서히 증가하였으며 Proteobacteria와 Verrucomicrobia 문의 점유율은 증가하고 Chloroflexi와 Spirochaetes 문의 점유율은 감소한 것으로 나타나 엔도설판 처리가 토양세균 군집구조를 변화시키는 것을 확인하였다. 엔도설판 처리 시 Sphingomonas와 Burkholderia 속에 속하는 OTU의 점유율이 배양 초기에 높게 나타났으며 Pseudonocardia와 Opitutus 속에 속하는 OTU의 점유율은 배양 후기에 높게 나타났다. 이전 연구에서 Sphingomonas, Burkholderia, Pseudonocardia 속에 속하는 균주들이 엔도설판을 분해하였으므로 이 속에 속하는 OTU들이 토양에서 엔도설판의 분해에 단계적으로 관여했을 것으로 추정된다.

• 한국토양비료학회지
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• 제27권4호
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• pp.309-314
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• 1994

토양현탁액중(土壤懸濁液中)에 유기염소계(有機鹽素系)인 펜타클로로페놀과 서로 다른 영양원(營養源)을 첨가(添加)하였을 때 이로 인한 총세균(總細菌)과 약제분해균(藥劑分解菌) 및 첨가(添加)된 물질(物質)의 화학적변화(化學的變化)를 검토(檢討)하였다. 총세균수(總細菌數) 및 그람음성균수(陰性菌數)는 배양후(培養後) 1주째에 모든 처리구(處理區)에서 가장 높았고, 그 이후 서서히 감소(減少)하였으며 무처리(無處理)에 비하여 양분처리구(養分處理區)에서 높았다. 특히 배양(培養) 5일째까지 글루코스 첨가구(添加區)에서 가장 높았다. PCP분해균수(分解菌數)는 양분무처리(養分無處理)인 대조구(對照區)에서 배양후(培養後) 4주째까지 증가(增加)한 후 약간 감소(減少)하였으나 모든 양분처리구(養分處理區)에서는 초기부터 감소(減少)하기 시작하여 2주째 이후에는 3 log $cells/m{\ell}$이하 이었다. 그 결과 PCP의 소실(消失)도 PCP만 첨가(添加)했을 경우가 PCP와 영양원(營養源)을 첨가(添加)했을 경우보다 빨랐다. 현탁토양내(懸濁土壤內)의 잔류양분(殘留養分)의 함량(含量)은 배양(培養) 1주(週)까지 영양원첨가구(營養源添加區) 모두에서 빠르게 분해(分解)되었으며 글루코스의 분해(分解)가 글루탐산이나 글리신보다 약간 빨랐으나 5주째에는 처리간에 큰 차이가 없었다. pH의 변화(變化)는 모든처리에서 약간의 증가가 있으나 처리간의 증감(增減)에 다소 차이가 있었다.

• 한국토양비료학회지
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• 제20권2호
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• pp.193-197
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• 1987

우리나라 서남해(西南海) 간사지(干瀉地) 및 간척답토양(干拓沓土壤)에서 자생(自生)하는 벼과(科)(5종(種)), 석죽과(科)(2종(種)), 질경이과(科)(2종(種))식물(植物) 및 수도(水稻)(2품종(品種))의 뿌리에서 협생질소고정균(協生窒素固定菌)의 분리동정(分離同定) 결과(結果)는 다음과 같다. 1. 수답(水沓) 및 자생식물(自生植物)뿌리에서 24종(種)의 질소고정능(窒素固定能)이 높은 협생질소고정균(協生窒素固定菌)을 분리(分離)하였으며 분리(分離)된 세균(細菌)은 8종(種)의 Azospirillum 속(屬), 11종(種)의 Pseudomonas 속(屬), 2종(種)의 Agrobacterium 속(屬) 그리고 2종(種)의 Klebsiella 속(屬)의 세균(細菌)으로서 대체(大體)로 Azospirillum 속(屬)과 Pseudomonas 속(屬)의 세균(細菌)이 많았다. 2. 각종식물별(各種植物別) 협생질소고정균(協生窒素固定菌)의 종류(種類)는 수도(水稻)와 큰 개미자리 뿌리에서 Azospirillum 속(屬), Pseudomonas 속(屬), Agrobacterium 속(屬) 그리고 Klebsiella 속(屬)의 세균(細菌)이 갯쇠보리, 창질경이, 털질경이, 각시미꾸리광이, 및 물억새 뿌리에서 Pseudomonas 속(屬), 그리고 갯잔디에서 Azospirillum 속(屬)의 세균(細菌)이 각각(各各) 분리(分離)되었는데 그중 수도(水稻)와 큰개미자리가 타식물(他植物)뿌리보다 협생질소고정균(協生窒素固定菌)의 종류(種類)가 많았다. 3. 간척지토양수도(干拓地土壤水稻) 및 식물(植物)뿌리에서 분리(分離)된 세균(細菌)의 혈청면역학적동정결과(血淸免疫學的同定結果) 이들 협생질소고정균(協生窒素固定菌은 Azospirillum lipoferum, Pseudomonas sp, Agrobacterium radiobader, 및 Klebsiella planticola 였다.

• Journal of Plant Biotechnology
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• 제44권2호
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• pp.156-163
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• 2017

A greenhouse experiment was conducted for evaluation of ecological effects of transgenic melon plants in the rhizospheric soil in terms of soil properties, enzyme activities and microbial communities. Organic matter content of soil under transgenic melon plants was significantly higher than that of soil with non-transgenic melon plants. Significant variations were observed in organic matter, total P and K in soil cultivation with transgenic melon plants. There were also significant variations in the total numbers of colony forming units of fungi, actinomycetes and bacteria between soils treated with transgenic and non-transgenic melon plants. Transgenic and non-transgenic melon significantly enhanced several enzymes activities including urease, acid phosphatase, alkalin phosphatase, arysulphtase, ${\beta}$ glucosidase, dehydrogenase, protease and catalase. Soil polyphenoloxidase activity of $T_1$ transgenic melon was lower than that of $T_0$ transgenic melon and a non-melon plant during the same period. The first generation transgenic melon plants ($T_0$) showed significantly greater (p<0.05) effect on the activitiy of arylsulfatase, which increased from $2.540{\times}10^6CFU\;g^{-1}$ (control) to $19.860{\times}10^6CFU\;g^{-1}$ ($T_0$). These results clearly indicated that transgenic melon might change microbial communities, enzyme activities and soil chemical properties.

• 미생물학회지
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• 제21권1호
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• pp.7-14
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• 1983

In order to study the effects of cropping system and fungicide (Dachigaren) on soil microbes, the seasonal fluctuations of soil microbes in the fields of radish and Chinese cabbage including soil pH, Soil moisture content and soil temperature were investigated on every 15 day interval from the begining of March to late October in 1981. The population of total fungus peaked at the begining of July, while that of total bacteria, at the begining of August. They were affected by soil temperature, however pathogenic microbes seemed to be more related with host plants than the soil temperature, because pathogens showed high density through the whole cultivation period. The pathogenic microbes showed the density of order ; Xanthomonas, Erwinia, Pseudomonas, Agrobacterium and Corynebacterium. Xanthomonas, Erwinia and Pseudomonas, which induced radish and Chinese cabbage diseases were higher than Agrobacterium and Corynebacterium in population densigy. Bacterial soft rot occured at the density of Erwinia $5.9{\sim}6.6{\times}10^5/dry$ soil 1 gram. The density of microbes on continuous fields were higher than that of rotating fields, but there were no significant difference between treated fungicide plot and non treated in the density of microbes, also no difference between Chinese cabbage and radish growing fields.

• 미생물과산업
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• 제19권2호
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• pp.49-57
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• 1993

Chenges in respiration of the soils collected from the reclaimed tidal soil in Chogi-ri, Kanghwa Island and treated with organic matters are presented. The measurement of the respiration for the smaples, which were incubated for 0,2,4 and 5 weeks, were carried out by using Warburg's respirometer. While the respirations of the samples added by organic matters were increased 6.7 - 28.0 times compared with that 0 week during the incubation in case of 5-year soil, the respiration in case of 3-year soil were increased 3.3-11.8 times. Thus, the effect of adding organic matters on the respiration of the experimented soils, as this indicates, was much higher for the soil of 5-year area than that of 30-year area. And for the organic matters Salicornia was most effective and then Suaeda and Oryzae. The samples treated with Salicornia and Suaeda showed their highest respiration rate at the 4th week, but the one with Oryzae was measured to increase progressively during 5 weeks experimented. Regarding the salinity, content of organic matters and number of bacteria, in each intact soil experimented, 5-year soil samples had much poor habitat then 30-year soil for the activity of soil microorganisms, but according to the result mentioned above, it is firmly believed that the addition of organic matters on the saline soil is one of the best means to change the reclaimed tidal land into arable land with less time duration.

• KSBB Journal
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• 제27권2호
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• pp.75-85
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• 2012

Although, microbial arsenic mobilization by dissimilatory arsenate-reducing bacteria (DARB) and the practical use to the removal technology of arsenic from contaminated soil are expected, most previous research mainly has been focused on the geochemical circulation of arsenic. Therefore, in this review we summarized the previously reported DARB to grasp the characteristic for bioremediation of arsenic. Evidence of microbial growth on arsenate is presented based on isolate analyses, after which a summary of the physiology of the following arsenate-respiring bacteria is provided: Chrysiogenes arsenatis strain BAL-$1^T$, Sulfurospirillum barnesii, Desulfotomaculum strain Ben-RB, Desulfotomaculum auripigmentum strains OREX-4, GFAJ-1, Bacillus sp., Desulfitobacterium hafniense DCB-$2^T$, strain SES-3, Citrobacter sp. (TSA-1 and NC-1), Sulfurospirillum arsenophilum sp. nov., Shewanella sp., Chrysiogenes arsenatis BAL-$1^T$, Deferribacter desulfuricans. Among the DARB, Citrobacter sp. NC-1 is superior to other dissimilatory arsenate-reducing bacteria with respect to arsenate reduction, particularly at high concentrations as high as 60 mM. A gram-negative anaerobic bacterium, Citrobacter sp. NC-1, which was isolated from arsenic contaminated soil, can grow on glucose as an electron donor and arsenate as an electron acceptor. Strain NC-1 rapidly reduced arsenate at 5 mM to arsenite with concomitant cell growth, indicating that arsenate can act as the terminal electron acceptor for anaerobic respiration (dissimilatory arsenate reduction). To characterize the reductase systems in strain NC-1, arsenate and nitrate reduction activities were investigated with washed-cell suspensions and crude cell extracts from cells grown on arsenate or nitrate. These reductase activities were induced individually by the two electron acceptors. Tungstate, which is a typical inhibitory antagonist of molybdenum containing dissimilatory reductases, strongly inhibited the reduction of arsenate and nitrate in anaerobic growth cultures. These results suggest that strain NC-1 catalyzes the reduction of arsenate and nitrate by distinct terminal reductases containing a molybdenum cofactor. This may be advantageous during bioremediation processes where both contaminants are present. Moreover, a brief explanation of arsenic extraction from a model soil artificially contaminated with As (V) using a novel DARB (Citrobacter sp. NC-1) is given in this article. We conclude with a discussion of the importance of microbial arsenate reduction in the environment. The successful application and use of DARB should facilitate the effective bioremediation of arsenic contaminated sites.

• 자원환경지질
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• 제40권5호
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• pp.575-585
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• 2007

지하 심부 토양 및 퇴적물 내 토착 미생물의 활성화에 따른 중금속 거동을 이해하기 위하여, 독성 중금속으로 오염된 국내 일부 지역의 시료를 대상으로 혐기적 환경에서 유산염(lactate)을 탄소원으로 투입한 후 약 25일간에 걸친 비소 및 중금속(카드뮴, 구리, 납, 아연) 함량 변화를 관찰하였다. 실험 결과, 미생물이 투입된 시료의 경우 미생물이 투입되지 않은 비교시료에 비하여 용존 카드뮴, 납, 아연이 효과적으로 제거되었으며, 이는 토착 황산염 환원(sulfate-reducing) 박테리아의 활성화로 인해 생성된 환원상태의 황이 이들 중금속과 황화물을 형성하며 침전시켰기 때문으로 여겨진다. 비소의 경우, 미생물을 투입한 시료 중 황산염의 함량이 높은 덕음 토양에서는 제거율이 높은 반면 황산염의 함량이 상대적으로 낮은 화북 토양, 동두천 퇴적물에서는 지속적으로 그 함량이 증가하였다. 적절한 탄소원 및 황산염을 투입해 독성 중금속으로 오염된 지질 매체 내의 토착 미생물을 활성화시킨다면 이들 중금속의 원위치(in situ) 고정화를 통한 이동도 감소의 효과를 볼 수 있을 것으로 여겨지나, 비소로 동시에 오염된 경우 발생할 수 있는 비소 용출 가능성에 대한 고려가 필요하다.