• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2002년도 총회 및 춘계학술발표회
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• pp.22-25
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• 2002

The effect of in-situ chemical oxidation on the indigenous soil microorganisms (total microbes and PAH-degrading microbes) and contaminant removal were investigated. Field soil contaminated with diesel in gas station was collected and the soil was treated from 0 to 900 minutes by in-situ ozonation as chemical remediation. The treated soil samples were incubated with supplying oxygen during the 9 weeks to understand the characteristics of microbes regrowth, damaged by ozone. The sharp decrease of aromatic fraction and TPH was observed within 60 minutes of ozone application and aromatic fraction and TPH then slowly decreased. The phenanthren-degrading bacteria were the most sensitive to ozonation, because 1 hour of ozonation reduced the microbes from 10$^{6}$ CFU/g-soil to below detection limits.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2004년도 총회 및 춘계학술발표회
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• pp.39-42
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• 2004

Landfarming and a microbial agent, Bioil-D, were used to treat diesel-contaminated soil. The microbial agent was applied to the contaminated soil in a concentration of 5$\times$10$^2$ cfu/soil(g) and the total amount of microbial agent, 210$\ell$, was sprinkled on the soil four times for 24 days during 50 day-remediation period. The remediation goal, lower than 800mg/kg of TPH, was achieved from 5, 707 mg/kg of TPH within 50 days. The total number and activity of indigenous microorganisms were increased by 100 times after the microbial agent, Bioil-D, was applied to the contaminated soil.

• 환경정보
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• 제26권5_6호
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• pp.59-61
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• 2004

유류에 의한 오염토양의 정화방법에는 크게 물리화학적 처리기술과 생물학적인 처리기술로 구분할수 있으며 생물학적 처리기술은 물리화학적 처리기술에 비하여 복원 기간이 긴 반면 처리비용이 저렴하며 2차 오염원을 발생시키지 않는다는 장점이 있다.<중략>

• 한국농공학회논문집
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• 제49권1호
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• pp.67-76
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• 2007

Bioventing is commonly used for petroleum hydrocarbon (PHC) spills. This process provides better subsurface oxygenation, thus stimulating degradation by indigenous microorganisms. Therefore soil vapor monitoring points (VMPs) are extremely important in determining the potential effectiveness of bioventing and in long-term monitoring of bioventing progress. In this study in-situ soil gas monitoring well (GMW) was developed and presented the pilot test results which recover the contaminated site by bioventing method. The result of application was successful and it was expected that GMW developed could be applied to the evaluation procedure of bioventing effectiveness and long-term remediation potential.

• Journal of Microbiology and Biotechnology
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• 제15권5호
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• pp.1087-1093
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• 2005

The population diversity and seasonal changes of bacterial communities in rice soils were monitored using both culture-dependent approaches and molecular methods. The rice field plot consisted of twelve subplots planted with two genetically-modified (GM) rice and two non-GM rice plants in three replicates. The DGGE analysis revealed that the bacterial community structures of the twelve subplot soils were quite similar to each other in a given month, indicating that there were no significant differences in the structure of the soil microbial populations between GM rice and non-GM rice during the experiment. However, the DGGE profiles of June soil after a sudden flooding were quite different from those of the other months. The June profiles exhibited a few intense DNA bands, compared with the others, indicating that flooding of rice field stimulated selective growth of some indigenous microorganisms. Phylogenetic analysis of l6S rDNA sequences from cultivated isolates showed that, while the isolates obtained from April soil before flooding were relatively evenly distributed among diverse genera such as Arthrobacter, Streptomyces, Terrabacter, and Bacillus/Paenibacillus, those from June soil after flooding mostly belonged to the Arthrobacter species. Phylogenetic analysis of 16S rDNA sequences obtained from the soil by cloning showed that April, August, and October had more diverse microorganisms than June. The results of this study indicated that flooding of rice fields gave a significant impact on the indigenous microbial community structure; however, the initial structure was gradually recovered over time after a sudden flooding.

• Preventive Nutrition and Food Science
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• 제9권2호
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• pp.138-143
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• 2004

Soybean curd residues (SCR) obtained from hot and cold manufacturing processes were fermented by indigenous microorganisms, Lactobacillus rhamnosus LS and Bacillus firmus NA-l for 15 h at 37$^{\circ}C$. The pH, acidity, viable cell counts, and tyrosine content were evaluated in samples with variations in sugar, starter and type of SCR. The raw Doowon SCR (D-SCR, cold-processed) fermented by indigenous microorganism had a 0.9% acidity and 6.7 ${\times}$ 10$^{7}$ CFU/g viable cell counts, compared with the 0.11 % acidity and 6.7 ${\times}$ 10$^{6}$ CFU/g viable cell counts of raw fermented Pulmuwon SCR (P-SCR, hot-processed). After fermentation of raw P-SCR with 1 % glucose and 1 % L. rhamnosus LS starter, the viable cell counts, tyrosine content and acidity were 4.7 ${\times}$ 10$^{8}$ CFU/g, 16.3 mg% and 0.9%, respectively. In addition, the raw P-SCR fermented with Bacillus firmus NA-l as co-starter had a 0.45% acidity, 2.4 ${\times}$ 10$^{8}$ CFU/g lactic acid bacteria, and 3.3 ${\times}$ 10$^{6}$ CFU/g Bacillus sp. In particular, the tyrosine content was increased 5 fold. The drying of fermented SCR was completed by hot-air drying (5$0^{\circ}C$) within 12 h; the dried P-SCR and D-SCR had 1.8 ${\times}$ 10$^{7}$ CFU/g and 5.3 ${\times}$ 10$^{6}$ CFU/g viable cell counts, respectively. The concentrate of methanol extract from fermented D-SCR inhibited the initial cell growth of E. coli, Staphylococcus aureus and Pseudomonas aeruginosa in liquid culture.

• Korean Chemical Engineering Research
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• 제52권1호
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• pp.92-97
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• 2014

퍼클로레이트($ClO_4^-$)는 지표수는 물론이고 토양지하수의 신규 오염물이다. $ClO_4^-$는 요오드가 갑상선에 흡수되는 것을 방해하므로 갑상선 호르몬 생성을 저하시킨다. $ClO_4^-$는 물에서 매우 용해도가 높고 안정적이라는 특징으로 인해 $ClO_4^-$를 환원하는 세균(PRB)에 의한 생분해가 자연저감의 가장 중요한 요인으로 여겨지고 있다. 산업단지 내 하천은 점 또는 비점오염원으로부터 배출된 $ClO_4^-$에 오염될 잠재성이 있다. 그래서 본 연구에서는 구미지역 산업단지 내 하천에서 물시료를 채취하여 하천미생물의 $ClO_4^-$ 분해 잠재능을 회분배양으로 조사하였다. 외부 전자공여체를 첨가하지 않고 83시간 동안 배양한 결과 모든 시료는 $ClO_4^-$ 제거효율이 0.77% 이하로 매우 낮은 것으로 나타났다. 그러나 외부 전자공여체(acetate, thiosulfate, $S^0$, 또는 $F^0$)를 첨가한 경우는 제거효율이 최고 100%로 나타났고, 첨가된 전자공여체의 종류와 시료채취지점에 따라 제거효율은 다양한 것으로 나타났다. 본 연구에서 사용한 전자공여체 중에서는 acetate를 사용했을 때 $ClO_4^-$분해효율이 가장 우수한 것으로 나타나 종속영양방식 PRB의 활성이 우세함을 알 수 있었다. 본 연구의 결과는 산업단지 내 하천 미생물에 의한 $ClO_4^-$ 자연저감에 대한 기초정보를 제공하여 원위치 생물복원처리에서 $ClO_4^-$ 생분해를 증진하기 위한 전략마련에 유용하게 사용될 것이다.

• 환경생물
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• 제29권3호
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• pp.195-201
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• 2011

Today, the weather is changing continually, due to the progress of global warming. As the weather changes, the habitats of different organisms will change as well. It cannot be predicted whether or not the weather will change with each passing day. In particular, the biological distribution of the areas climate change affects constitutes a major factor in determining the natural state of indigenous plants; additionally, plants are constantly exposed to rhizobacteria, which are bound to be sensitive to these changes. Interest has grown in the relationship between plants and rhizopheric microorganisms. As a result of this interest we elected to research and experiment further. We researched the dominant changes that occur between plants and rhizospheric organisms due to global warming. First, we used temperature as a variable. We employed four different temperatures and four different sites: room temperature ($27^{\circ}C$), $+2^{\circ}C$, $+4^{\circ}C$, and $+6^{\circ}C$. The four different sites we used were populated by the following strains: Pinus densiflora, Pinus koraiensis, Quercus acutissima. We counted colonies of these plants and divided them. Then, using 16S rRNA analysis we identified the microorganisms. In conclusion, we identified the following genera, which were as follows: 24 strains of Bacillus, 6 Paenibacillus strains, 1 Pseudomonas strains. Among these genera, the dominant strains in Pinus densiflora was discovered in the same genus. Additionally, those of Pinus koraiensis and Quercus acutissima changed in both genus and strains which changed into the Bacillus genus from the Paenibacillus genus at $33^{\circ}C$.

• 환경생물
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• 제22권
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• pp.38-46
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• 2004

다환 방향족 탄화수소(PAHs)에 의한 오염이 미생물군집구조에 미치는 영향을 파악하기 위하여 연안에 가까운 광양만 퇴적토를 대상으로 하여 2000년 3월과 8월 2회에 걸쳐 PAHs 오염도와 말단제한절편 다형성 (T-RFLP)분석방법을 이용하여 미생물 군집구조를 조사하였다. T-RFLP방법으로 조사한 미생물 군집은 계절에 따라 군집이 구분되었으며 월내천입구에 위치한 정점 1에서 3월에 다른 정점과 다른 독특한 군집구조를 형성하였다. 또한 상대적으로 PAHs 오염도가 높은 정점들에서 미생물 다양성도 높은 것으로 나타났다. PAHs 농후배양시료에서의 미생물군집구조 변화와 비교해 볼 때 조사대상지역 퇴적토의 미생물 군집구조는 PAHs의 오염에 부분적으로는 영향을 받지만 군집구조를 결정하는 주된 요인은 온도, 입도, 유기물 함량 등과 같은 환경요인인 것으로 사료된다.

• Journal of Microbiology
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• 제34권4호
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• pp.320-326
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• 1996

To analyze the effects of host versus plasmid on survival of 2, 4-degrading bacteria in environmental samples, strains Pseudomonas cepacia/pJP4, Alcaligenes JMP228/pJP4, P. cepacia/p712, and Alcaligenes JMP228/p712 were separately inoculated into samples of field soil, paddy soil, lake water, and river water, and then the changes of their populations were measured. The strains used contained a 2, 4-D degradative plasmid, either pJP4 conferring fast-growing property to the host or p712 conferring slow-growing property, and were resistant to antibiotics such that the inoculated strains could be enumerated against the indigenous microbial populations. In sterile environmental samples, these strains were stably maintained at the levels used for inoculation, except in sterile paddy soil where Alcaligenes JMP228 strains died drapidly. In natural soil samples for four strains declined steadily with time, but in naturla water samples their polulations fell rapidly at the early phase and then remained almost constant. When the environmentla samples were treated with 2, 4-D, P. cepacia/pJP4 and P. cepacia/p712 maintained significant numbers, while Alcaligenes JMP228/pJP4 and Alcaligenes JMP228/p712 declined significantly in most of the samples. The results indicated that the survivability of genetically modified microorganisms could vary depending on the environments and that their abundance in the environments under s2, 4-D selection was markedly influenced by the nature of the 2, 4-D degradative plasmid as well as type of the host strain.