• 생명과학회지
• /
• 제21권11호
• /
• pp.1599-1606
• /
• 2011

유류분해에 있어 혼합미생물제제의 효과를 평가하기 위해 미생물제제의 처리성능과 microcosm test를 수행하였다. 유류분해세균은 0.5% Arabian heavy crude oil을 유일 탄소원으로 제공된 최소배지를 이용한 연속적인 농후배양을 통하여 분리하였다. 우수 유류분해 미생물조합인 3종의 균주(BS1, BS2, BS4)는 MSM배지에서 5일의 배양기간 동안 지방족 탄화수소를 48.4%, 방향족 탄화수소를 30.5% 생분해하였다. 처리성능 및 microcosm test는 Arabian heavy crude oil을 첨가한 후 3가지 처리조건인 무처리, 무기영양염처리 그리고 무기영양염 및 혼합미생물처리조건에서 유류화합물의 생물분해에 미치는 영향을 조사하였다. 무기영양염처리구와 무기영양염 및 혼합미생물처리구에서 지방족 탄화수소의 분해율은 실험기간 동안 유의하게 향상되었으며 두 실험구간 유의한 차이는 관찰되지 않았다. 그러나 무기영양염 및 혼합미생물처리구에서 방향족 탄화수소의 생분해율은 무기영양염제만을 처리한 시험구와 비교하여 처리성능 시험의 경우 50% 그리고 microcosm test의 경우 13%를 향상시켰다. 본 연구의 결과로부터 혼합미생물제제는 실험실, 처리성능 및 microcosm test에서 지방족뿐만 아니라 방향족 탄화수소의 생물분해를 촉진하였다. 특히 혼합미생물제제는 방향족 탄화수소의 제거를 위한 생물정화기술의 적용에 있어 유용한 도구로 판단된다.

• 상하수도학회지
• /
• 제18권3호
• /
• pp.307-311
• /
• 2004

The objective of this work is to evaluate the hypothesis that a good technique for supplying oxygen to the saturated zone in the presence of light nonaqueous phase liquid (LNAPL) pool contamination at the water table is to pass air through the unsaturated zone above the pool. This hypothesis was evaluated in experimental studies performed using a bench-scale, sand-tank reactor, Steady-state abiotic experiments in the sand-tank reactor with air flowing through the reactor headspace demonstrated that oxygen supply through the water table interface into the saturated zone was enhanced when an LNAPL (dodecane) pool was present at the water table. These experimental results confirmed the hypothesis that an LNAPL pool can serve as a high concentration oxygen source to the oxygen-limited area beneath the pool and, as a result, enhance the in situ biodegradation rate.

• KSBB Journal
• /
• 제27권5호
• /
• pp.281-288
• /
• 2012

Phytoremediation-the use of plants for the in situ treatment of contaminated soil and water-has recently emerged as an inexpensive and user-friendly alternative to traditional methods of environmental clean-up. The present article outlines the characteristics of phytoremediation based on accumulated research evidence, along with discussions on its advantages and disadvantages. It further reviews various mechanisms involved in the phytoremediation processes: phytoextraction, rhizofiltration, phytostabilization, phytovolatilization and phytodegradation. Along the way, the author summarizes examples of its applications to environmental pollution control. These include wastewater treatment, removal of heavy metals, and hydrocarbons, remediation of recalcitrant contaminants, phytoremediation of radionuclides, and application of transgenic plants for enhanced biodegradation and phytoremediation. The remainder of the article briefly concludes with directions for future research.

• 한국지하수토양환경학회:학술대회논문집
• /
• 한국지하수토양환경학회 2003년도 총회 및 춘계학술발표회
• /
• pp.368-371
• /
• 2003

Leaking underground storage tanks are a major source of groundwater contamination by petroleum hydrocarbons. Bioremediation of aromatic hydrocarbons in groundwater and sediments is often limited by dissolved oxygen. Aerobic bioremediation has been highly effective in the remediation of many fuel releases, but Many aromatic hydrocarbons degrade very slowly under anaerobic conditions. Nitrate is a good alternative electron acceptor to oxygen and denitrifying bacteria are commonly found in the subsurface and in association with contaminated aquifer materials. Because nitrate is less expensive and more soluble than oxygen. it may be more economical to restore fuel-contaminated aquifers using nitrate rather than oxygen. This study show that biodegradation of BTEX and MTBE is enhanced by the nitrate-amended microcosms under aerobic/anaerobic conditons. Although aromatic hydrocarbons degrade very slowly under anaerobic conditions. Biodegradaton was observed for all of the test compounds.

• Fisheries and Aquatic Sciences
• /
• 제13권1호
• /
• pp.12-17
• /
• 2010

This study was conducted to evaluate the potential of a microbial fermentation procedure to improve the functional qualities of seaweeds. Aspergillus oryzae, which has been used in traditional Korean fermented foods, was inoculated and cultivated in an aqueous extract of sea tangle (Laminaria japonica). Fermentation of the sea tangle extract by A. oryzae for 4 days resulted in a 3-fold increase in $\gamma$-aminobutyric acid (GABA) content. GABA is known to be a bioactive compound. Fungal fermentation of the extract also enhanced its antioxidant activity and increased its total content of phenolic compounds. It was assumed that these changes stemmed from the biodegradation of active compounds of the sea tangle packaged within its rigid structural matrix or occurred as result of fungal fermentation. These results suggested that the application of microbial fermentation to the processing of seaweeds will help in the development of processed foods to meet consumer demands.

• 한국지하수토양환경학회:학술대회논문집
• /
• 한국지하수토양환경학회 1998년도 총회 및 춘계 학술발표회 논문집
• /
• pp.53-60
• /
• 1998

The effect of chemically oxidized intermediated of PAH compounds on the degradation of the parent PAHs was characterized and evaluated for the context of cooxidation. Anthracene and pyrene exhibited extensive degradation (mean percent removal of 57.5%) after 28 days of incubation by introducing the Fenton oxidation intermediate of the PAH compounds, while unoxidized anthracene and pyrene exhibited 12.5% removal. Dehydrogenase activities for the oxidized PAH studies ware enhanced two to five folds to the unoxidized PAHs studies. The chemical oxidation products can serve as a structually very similar analogue substrates for a consortia of soil microorganisms and as a metabolic intermediates in the biodegradation sequence of the parent PAH compounds. These results may be interpreted in the context of cooxidation mechanism whereby high recalcitrant PAH compounds are biodegraded in the soil and suggest a potential tool for bioremediation of PAHs contaminated soils and protection of groundwater.

• 미생물학회지
• /
• 제42권1호
• /
• pp.7-11
• /
• 2006

조류의 효과적인 제어방법 개발의 일환으로 해양암석분말의 효과를 보기위하여 해양암석분말과 곰팡이 배양 상등액을 이용하여 해양조류 제거율을 조사하였다. 편조류인 H. akashiwo와 P.minimum는 해양암석 분말을 30g/1의 농도로 살포한 실험군에서 높은 구제효과를 나타내었고, P. oxalicum (HCLE-34)배양상등액 살포는 5 mg/l 살포군에서도 구제효과를 나타내었다. 혼합 살포군에서도 배양 상등액 단독 살포군에서와 동등한 정도의 구제효과를 나타내었고, 완충용액 (pH 2.8)은 15 mg/l 살포군에서 60분 경과 후 75%의 구제효과를 나타내었으나, 전자현미경적 관찰에서는 암석분말과 배양 상등액 혼합 살포군, 배양 상등액 살포군, 암석분말 살포군 및 완충용액 살포군 순으로 세포의 파괴정도가 관찰되었다. 이러한 결과는 암석분말과 곰팡이 배양상등액이 해양에서 발생되는 편조류의 대발생을 조절할 수 있는 물질로 작용함을 시사한다.

• 한국토양환경학회지
• /
• 제3권2호
• /
• pp.115-125
• /
• 1998

오염된 토양 중 phenanthrene의 분해에 미치는 비이온계 계면활성제와 생물계면활성제의 영향을 살펴보았다. 비이온계 합성 계면활성제로 polyoxyethylene oreyl esterC$^{17}$ H$^{33}$ COO($C_2$$H_4$O)nH) 와 생물계면활성제인 sophorolipid를 적용하였다. 계면활성제의 농도, 수분함량, 접종균 처리 방법 및 종류, pH, 온도, 부가영양분 등의 변수들이 phenanthrene의 생분해에 미치는 영향을 비교실험 하였다. 계면활성제 농도가 CMC이하의 경우 계면활성제는 phenanthrene의 생분해성을 촉진하였으나, CMC 값 이상의 영역에서는 계면활성제가 미생물의 phenanthrene분해작용을 저해하였다. 30%의 수분함량과 pH 7, $30^{\circ}C$에서, 부가영양분으로 glucose를 10g/L수준으로 첨가하였을 때 좋은 분해도를 나타내었다. 충진제로 짚이 첨가되는 경우 토양 : 짚의 중량비가 5:2이고, 수분함량이 50%인 경우 phenanthrene의 분해가 촉진되었다.

• 한국지하수토양환경학회지:지하수토양환경
• /
• 제6권2호
• /
• pp.39-47
• /
• 2001

회분식 세척실험에서 적용된 혼합계면활성제 중 $POE_5$ + $POE_14$, SDS+$POE_5$가 endosulfan의 탈착에 효율이 우수한 것으로 나타났으며, 독성실험 결과 SDS+POE$_{5}$는 미생물의 활성을 다소 저해시키는 경향이 있어 $POE_5$ + $POE_14$ (1:1) 1%를 세척제로 선정하였다. In-Situ flushing 실험에서는 세척용액의 주입 flux가 1.5L/min/m$^2$일 때 67%의 제거효율을 얻을 수 있었으며, 보조용매로서 메탄올과 에탄올을 첨가한 경우에는 각각 75%와 81%의 제거효율을 보였다. In-situ flushing기법의 적용에 따른 농도 저감이 생물학적 분해에 미치는 영향을 알아보기 위하여, 초기 농도 13mg/kg dry soil과 3mg/kg dry soil인 토양을 생물학적으로 처리한 결과 제거 효율은 각각 86% 및 81%였으며, 2가지 토양 모두 24시간 이후에는 미생물에 의한 작용이 크지 않은 것으로 나타났다. 이것은 토양상에서 용액상으로의 물질전이 속도가 율속 단계로 작용하고 있기 때문이라 판단된다. 토양에 잔류하는 계면활성제가 생물학적 분해에 미치는 영향에 대하여 검토한 결과, 잔류하는 계면활성제에 의해 물질전이 속도가 향상되어 생분해가 지속적으로 일어났으며 초기 농도 3mg/kg dry soil인 경우 120시간이 경과한 후 89%의 제거효율을 나타내었다. 계면활성제와 보조용매가 동시에 잔류하는 경우에는 계면활성제에 대한 순응기간이 보다 길어지는 것을 알 수 있었으며, 메탄올과 에탄올의 경우 각각 84% 및 83%의 제거효율을 나타내었다.

• 상하수도학회지
• /
• 제32권2호
• /
• pp.159-168
• /
• 2018

Climate change is believed to increase the amount of dissolved organic matter in surface water, as a result of the release of bulk organic matter, which make difficult to achieve a high quality of drinking water via conventional water treatment techniques. Therefore, the natural water treatment techniques, such as managed aquifer recharge (MAR), can be proposed as a alternative method to improve water quality greatly. Removal of bulk organic matter using managed aquifer recharge system is mainly achieved by biodegradation. Biodegradable dissolved organic carbon (BDOC) and assimilable organic carbon (AOC) can be used as water quality indicators for biological stability of drinking water. In this study, we compared the change of BDOC and AOC with respect to pretreatment methods (i.e., ozone or peroxone). The oxidative pretreatment can transform the recalcitrant organic matter into readily biodegradable one (i.e., BDOC and AOC). We also investigated the differences of organic matter characteristics between BDOC and AOC. We observed the decreases in dissolved organic carbon (DOC) and the tryptophan-like fluorescence intensities. Liquid chromatographic - organic carbon detection (LC-OCD) analysis also showed the reduction of the low molecular weight (LMW) fraction (15% removed, less than 500 Da), which is known to be easily biodegradable, and the biopolymers, high molecular weight fractions (66%). Therefore, BDOC consists of a broad range of organic matter characteristics with respect to molecular weight. In AOC, low molecular weight organic matter and biopolymers fraction was reduced by 11 and 6%, respectively. It confirmed that biodegradation by microorganisms as the main removal mechanism in AOC, while BDOC has biodegradation by microorganism as well as the sorption effects from the sand. $O_3$ and $O_3+H_2O_2$ were compared with respect to biological stability and dissolved organic matter characteristics. BDOC and AOC were determined to be about 1.9 times for $O_3$ and about 1.4 times for $O_3+H_2O_2$. It was confirmed that $O_3$ enhanced the biodegradability by increasing LMW dissolved organic matter.