• KSBB Journal
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• 제9권5호
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• pp.469-474
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• 1994

본 연구의 목적은 시판 퍼l녹시계 제초제 2,4-D의 생물학적 처리의 가능성을 평가하기 위한 것이다. 시판 페녹시계 제초제는 2,4-0 아민염 으로셔 2,4-0( 40%)와 용제 (60 % )로 구성 되었다. 2,4-D에서 농화배양에 의해 얻어진 미생물 컨소시염은 탄소원 빛 에너지원으로서 2,4-0를 이용하였다. 이 설험에서 2,4-D분해의 최적 pH 와 기 질농도는 각각 7.0과 54mg/ E 였다. Yeast extract와 ascorbic acid의 첨가는 2,4-0의 분해 와 미생물의 생장을 촉진시켰다. 2,4-0를 정량하기 위해 HPLC가 사용되었으며 그 과정에셔 중간대사물질로셔 2,4-0CP가 분리되었다. GC MS는 2,4-0CP를 입증하기 위하여 사용되였다. 배양중의 UV scans 결과, 2,4-0의 최대흡광치는 배양이 진행되는 동안 감소되었으나, spectral 및 peak 변화는 보여주지 않았다.

• Biotechnology and Bioprocess Engineering:BBE
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• 제11권6호
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• pp.471-476
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• 2006

Pseudomonas aeruginosa F722 produces a biosurfactant (BS) during its degradation of carbon and hydrocarbon compounds. The culture conditions for upgrading the biosurfactant productivity were investigated. The concentration of the biosurfactant produced by P. aeruginosa F722 was 0.78 g/L in C-medium; however, this increased to 1.66 g/L in BS medium, which was experimentally adjusted to optimal conditions. $NaNO_{2}$ was found to be most effective for microbial growth, with an $O.D_{600nm}$ of 1.18 for 0.1 % $NaNO_{2}$. Microbial growths, according to the $O.D_{600nm}$ were 2.53, 2.68, 2.89, and 2.87 for glucose, glycerol, $n-C_{10},\;and\;n-C_{22}$, respectively. Clear zone diameters (cm), indicating biosurfactant activity, were 9.0, 8.8, 5.7, and 8.5 for glucose, glycerol, $n-C_{10},\;and\;n-C_{22}$, respectively. Microbial growth was not consistent with the biosurfactant activity. The best biosurfactant activity was found with a C/N ratio of 20. Under optimal culture condition, the average surface tension decreased from 70 to 30 mN/m after 5 days. With aeration of 1.0 vvm, the biosurfactant produced increased to 1.94 g/L (up to 20%) compared to that of 1.66 g/L with no aeration. With aeration, the velocities of glucose degradation during both the log and stationary growth phases increased from 0.25 and $0.18\;h^{-1}$ to 0.33 and $0.29\;h^{-1}$, respectively, and the time for the culture to arrive at the maximum clear zone diameter became shorter, from 80 down to 60 h with no aeration.

• Journal of Microbiology and Biotechnology
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• 제26권8호
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• pp.1409-1419
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• 2016

The effect of pH on propionate degradation in an upflow anaerobic sludge blanket (UASB) reactor containing propionate as a sole carbon source was studied. Under influent propionate of 2,000 mg/l and 35℃, propionate removal at pH 7.5-6.8 was above 93.6%. Propionate conversion was significantly inhibited with stepwise pH decrease from pH 6.8 to 6.5, 6.0, 5.5, 5.0, 4.5, and then to 4.0. After long-term operation, the propionate removal at pH 6.5-4.5 maintained an efficiency of 88.5%-70.1%, whereas propionate was hardly decomposed at pH 4.0. Microbial composition analysis showed that propionate-oxidizing bacteria from the genera Pelotomaculum and Smithella likely existed in this system. They were significantly reduced at pH ≤5.5. The methanogens in this UASB reactor belonged to four genera: Methanobacterium, Methanospirillum, Methanofollis, and Methanosaeta. Most detectable hydrogenotrophic methanogens were able to grow at low pH conditions (pH 6.0-4.0), but the acetotrophic methanogens were reduced as pH decreased. These results indicated that propionate-oxidizing bacteria and acetotrophic methanogens were more sensitive to low pH (5.5-4.0) than hydrogenotrophic methanogens.

• 한국지하수토양환경학회지:지하수토양환경
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• 제26권4호
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• pp.20-26
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• 2021

In this work, an indigenous microbial consortium was obtained by selectively cultivating microbes using a long-aged petroleum-contaminated soil (Kuwait) containing recalcitrant petroleum hydrocarbons. The obtained microbial consortium was able to grow on and degrade the remaining petroleum hydrocarbons which could not have been utilized by the indigenous microbes in the original Kuwait soil. The following microbial community analysis using 16S rRNA gene sequencing suggested that the enhanced degradation of the remaining recalcitrant petroleum hydrocarbons by the novel microbial consortium may have been attributed to the selected bacterial populations belonging to Bacillus, Burkholderia, Sphingobacterium, Lachnospiraceae, Prevotella, Haemophilus, Pseudomonas, and Neisseria.

• 한국미생물생명공학회:학술대회논문집
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• 한국미생물생명공학회 2000년도 추계 학술대회
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• pp.125-139
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• 2000

The differential enhanced degradation of cis- and trans-1,3-D was observed in the previous two studies performed by Ou et al. (1995) and especially Chung et al. (1999). This study was initiated to investigate the involvement of microorganisms in the differential enhanced degradation of the chemicals. As expected, microorganisms were responsible for the enhanced degradation of the chemicals. A mixed bacterial culture capable of degrading 1,3-D was isolated from an enhanced soil sample collected from a site treated with 1,3-D. Similar to the enhanced soil, the mixed culture degraded trans-1,3-D faster than cis-1,3-D. This mixed culture could not utilize cis- and trans-1,3-D as a sole source of carbon for growth. Rather, a variety of second substrates were evaluated to stimulate the differential enhanced degradation of the two isomers. As a result, the mixed culture degraded cis- and trans-1,3-D only in the presence of a suitable second substrate. Second substrates that had the capacity to stimulate the degradation included soil leachate, tryptone, tryptophan, and alanine. Other substrates tested, including soil extract, glucose, yeast extract, and indole (ailed to stimulate the degradation of the two isomers. Therefore, it appeared that the degradation of cis- and trans-1,3-D was a cometabolic process. The mixed culture was composed of four morphologically distinctive bacterial colonies.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2003년도 총회 및 춘계학술발표회
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• pp.360-363
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• 2003

Bioremediation is often used for in situ remediation of petroleum-contaminated site. We studied the microbial degradation of hydrocarbon in an artificially diesel contaminated soil in laboratory microcosm. In control soil, about 30% of the initial TPH was diminished and the degradation of diesel oil was significantly enhanced by the addition of bioremediation agent (70% of TPH reduction).

• 생명과학회지
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• 제24권8호
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• pp.887-894
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• 2014

유기염소계 난분해성 산업폐수처리에 효과적인 미생물제제 개발을 위하여 PCP (pentachlorophenol)와 TCE (trichloroethylene) 등과 같은 유기계 염소화합물이 오염되어있는 토양 및 산업폐수로부터 PCP 분해활성이 높은 GP5, GP19와 TCE 분해활성이 높은 GA6, GA15를 분리하였다. 이들 분리균주 GP5, GP19, GA6, GA15등은 Acetobactor sp., Pseudomonas sp., Arthrobacer sp., Xanthomonas sp.과 유사한 것으로 나타나 최종적으로 Acetobacter sp. GP5, Pseudomonas sp. GP19, Arthrobacer sp. GA6, Xanthomoas sp. GA15로 명명하였다. 유기염소계 산업폐수의 처리를 위한 복합미생물제제 OC17은 PCP와 TCE를 분해하는 4개의 분리 분리균주와 방향족화합물 분해균주인 Acinetobacter sp. KN11, Neisseria sp. GN13의 배양액을 혼합하여 제조하였다. 복합미생물제제 OC17은 $2.8{\times}10^9CFU/g$의 균체수를 갖고 있으며, 밀도는 $0.299g/cm^3$, 수분함량은 26.8%를 나타내었다. 복합미생물 제제 OC17은 PCP 500 mg/l가 포함되어있는 인공폐수를 이용한 실험에서 배양 65시간에 87%의 분해효율을 나타내었고, TCE (300 uM)의 분해효율은 배양 50시간에 90%의 분해효율을 나타내었다. 복합미생물제제 OC17을 이용한 유기 염소계 산업폐수의 처리효율 시험을 위한 연속배양 실험 에서 10일간 처리 하였을 때 91%의 COD 제거효율을 나타내었다.

• 한국미생물·생명공학회지
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• 제39권3호
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• pp.301-307
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• 2011

유류로 오염된 토양을 토양미생물 복원제를 첨가한 후 다양한 조건에서20일 동안의 유류저감효과를 알아보았다. 실험조건은 유류로만 오염된 토양(DS), 토양미생물 복원제를 20%(w/w)가 되도록 첨가한 유류로 오염된 토양(DSP), 토양 미생물 복원제를 넣은 후 pH를 중성으로 보정한 유류로 오염된 토양(DSP-1), 토양미생물 복원제와 촉진제를 넣은 유류로 오염된 토양(DSP-2), 토양미생물 복원제와 촉진제를 넣은 후 pH를 중성으로 보정한 유류로 오염된 토양(DSP-3)을 설정하였다. 실험 결과 pH를 보정한 토양미생물 복원제를 첨가한 유류오염토양은 탈수소 효소 활성과 TPH 저감에서의 효능이 우수하였다. 실험이10일 경과되었을 때 탈수소 효소 활성이 가장 높은 DSP-1 토양이 TPH 역시 가장 활발히 분해했다. 결과적으로 초기 10일의 배양기간 동안 토양미생물 복원제를 첨가한 토양은 대조군에 비해 38% 가량의 TPH 저감상승효과를 볼 수 있다. 토양미생물 복원제의 첨가를 통해 초기 저감속도를 올려줄 수 있으며, 최종적으로도 비 첨가군에 비해 높은 저감효율을 기대할 수 있다. 토양미생물 복원제를 유류오염토양을 복원한다면 초기 오염물질을 빠르게 처리할 수 있지만 미생물 활성은 pH, 온도 등 환경 인자에 많은 영향을 받으므로 토양미생물 복원제의 효율을 최대화하기 위해서는 환경 인자를 분석하여 이를 바탕으로 복원을 진행한다면 오염물질 정화 효율을 향상시킬 수 있을 것이다.

• Journal of Microbiology and Biotechnology
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• 제17권1호
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• pp.67-73
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• 2007

The present study compared the microbial diversity and activity during the application of various bioremediation processes to crude oil-contaminated soil. Five different treatments, including natural attenuation (NA), biostimulation (BS), biosurfactant addition (BE), bioaugmentation (BA), and a combined treatment (CT) of biostimulation, biosurfactant addition, and bioaugmentation, were used to analyze the degradation rate and microbial communities. After 120 days, the level of remaining hydrocarbons after all the treatments was similar, however, the highest rate (k) of total petroleum hydrocarbon (TPH) degradation was observed with the CT treatment (P<0.05). The total bacterial counts increased during the first 2 weeks with all the treatments, and then remained stable. The bacterial communities and alkane monooxygenase gene fragment, alkB, were compared by denaturing gradient gel electrophoresis (DGGE). The DGGE analyses of the BA and CT treatments, which included Nocardia sp. H17-1, revealed a simple dominant population structure, compared with the other treatments. The Shannon-Weaver diversity index (H') and Simpson dominance index (D), calculated from the DGGE profiles using 16S rDNA, showed considerable qualitative differences in the community structure before and after the bioremediation treatment as well as between treatment conditions.

• 한국지하수토양환경학회지:지하수토양환경
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• 제12권5호
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• pp.54-63
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• 2007

중질유로 오염된 토양의 생물학적 정화에 있어 amendment의 처리효과를 보고자 포장에서 pilot 규모로 105일간 실험을 수행하였다. 실험기간 중 주기적으로 토양시료를 채취하여 유류성분과 생물학적 활성과 관련된 분석을 수행하였는데 퇴비의 처리구들에서 쌀겨+무기양분처리구에 비하여 유류성분의 분해활성이 현저하게 증가함을 확인할 수 있었다. 105일 경과 후 amendment 처리구들에서는 초기농도 $6,205{\pm}173mgkg^{-1}$의 $33{\sim}45%$가 소실된 반면 무처리구에서는 8%만이 분해된 것으로 나타났다. 퇴비처리구들에서 무처리구 및 쌀겨처리구에 비해서 높은 중질유 분해활성을 관찰할 수 있었는데 실험기간 중 모니터링한 생물학적 지표들 중 soil respiration, dehydrogenase, lipase, urease 등의 효소활성이 쌀겨처리구에 비해 현저하게 높은 활성이 관찰되었고 이들 미생물학적 지표들과 중질유의 분해정도 사이에는 높은 상관관계가 존재하였다(p < 0.01).