• Environmental Engineering Research
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• 제21권1호
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• pp.52-57
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• 2016

Sediment is a useful natural source but deteriorated continually by anthropogenic and industrial sources. Therefore, it is imperative to search a suitable method for improving or restoring sediment quality. Sediment has been tested to identify the effects of some external agents on a polluted area for 28 days. Chemical analysis and total viable counts (TVC) test have been conducted for 4 days interval to assess their performance. The analyses of chemical oxygen demand (COD), acid volatile sulfide (AVS), total phosphorous (T-P), total nitrogen (T-N) indicate that the chemical agents was more efficient to improve sediment quality whereas the microbial agent was more efficient for nutrient releasing from sediment. Oxygen releasing property of the chemical agent was thought to be providing with more congenial environment for the higher growth of the bacterial community than the direct application of microbial agents.

• 한국항해항만학회지
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• 제33권2호
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• pp.161-166
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• 2009

Lactobacillus sp., Acetobacter sp. and yeast were the most dominant organisms in the EM stock culture and subculture product. Lactic acid bacteria and yeast were able to grow in the fermentation process utilizing seawater. EM treatment of higher concentrations using EM stock culture and EM clay balls (1% or 4%) contributed to an early removal of malodor and an increase of DO in the polluted sediments, indicating an odor-removing activity of EM. The EM treatment of higher concentrations (1% or 4%) somewhat appeared to modify the microbial communities within the sediments, which was confirmed by existence of a few unique fragments from the stock culture based on PCR-DGGE. It still remains to be elucidated that EM cultures were directly involved in the malodor removal and potential sediment bioremediation.

• 한국환경과학회지
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• 제21권10호
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• pp.1187-1193
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• 2012

The aim of this research is to enhance the bottom environment of Geoje fish farm that has been severely contaminated. Treatment of microbial agent and/or calcium oxide significantly changed that environment: in ignition loss, either treatment (25% or 21%) showed better than mixed treatment (13.2%). In COD, the oxygen releasing agent or mixed treatment reduced the index by more than 20%. In T-P and T-N, the effects of $CaO_2$ on them were overwhelming (50% or more) meanwhile that of the microbial agent on them was less than 20%. Also, $CaO_2$ influenced on the microbial flora: Desulfobvibrio thermophilus, a sulfate reducing bacterium decreased in number, considering the increase of pH and rise of redox potential. In contrast, Pseudomonas sp., Pseudoalteromonas sp., Pseudomonas aeruginosa were remarkably dominant over other species with mixed treatment as a PCA analysis confirmed it.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2016년도 춘계학술대회
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• pp.132-134
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• 2016

The Study mainly focused on bioremediation of 16 types PAHs and heavy metals in contaminated marine sediments at filed scale study using slow release biostimulant ball (BSB) was investigated. In our experiment, filed scale study ($1m{\times}1m$) was performed and the effect of BSB on PAHs and heavy metals were analysed. BSB size and distance were determined and optimum size and distance were 3cm and 5.5cm respectively. BSB containing nutrients of acetate, nitrate and sulphate which can enhance the activity of microorganism to increase degrading capacity of PAHs and enhance the heavy metals stabilization also to decrease bioavailability. PAHs containing 16 types of 2, 3, 4, 5 and 6 rings compound PAHs were found and to degrade upto 100% in 2, 3 rings, upto 90 to 94% in 4 and 5 rings and 6 ring compound was degrade up to 70%. For heavy metals stabilization percentage was increased using BSB sediment and exchangeable portion was decreased and residual portion was increased in all analysed heavy metals. BSB enhance the PAHs degradation and stabilization of heavy metals percentages. BSB is a promising method for remediation of PAHs and heavy metals in contaminated marine sediments.

• Environmental Engineering Research
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• 제19권1호
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• pp.101-105
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• 2014

Three magnesium compounds, $MgO_2$, MgO, and $Mg(OH)_2$, which are supposed to supply oxygen continuously, were applied onto contaminated bay sediment and its ecology in order to activate the local microbial flora. Those compounds were found to reduce chemical oxygen demand (COD), total nitrogen (T-N), and total phosphorus (T-P). Magnesium oxide, in particular, reduced COD by 30% and T-N and T-P considerably. All compounds also suppressed the release of pollutants in the order $MgO_2$, MgO, and $Mg(OH)_2$. Analysis of microbial flora showed that the microbial group treated by $MgO_2$ and $Mg(OH)_2$ was predictably stable; meanwhile, that treated by MgO increased the number of species, but decreased the total number of microorganisms.

• Journal of Ecology and Environment
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• 제41권9호
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• pp.235-245
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• 2017

Background: Loading of excess nutrient via bioremediation of polluted sediment to overlying water could trigger anoxia and eutrophication in coastal area. The aim of this research was to understand the changes of overlying water features such as dissolved oxygen (DO); pH; oxidation reduction potential (ORP); $chlorophyll-{\alpha}$ ($Chl-{\alpha}$); and nitrogen nutrients ammonia ($N-NH_4{^+}$), nitrate ($N-NO_3{^-}$), and nitrite ($N-NO_2^-$) when the sediment was not treated (control) and treated by calcium peroxide for 5 weeks. Methods: The water samples were analyzed for measuring physical and chemical properties along with the sediment analyzed by polymerase chain reaction (PCR) including denaturing gradient gel electrophoresis (DGGE) for identifying the phylogenetic affiliation of microbial communities. Results: Results showed that due to the addition of calcium peroxide in sediment, the overlying water exposed the rise of dissolve oxygen, pH, and ORP than control. Among the nitrogen nutrients, ammonia inhibition was higher in calcium peroxide treatment than control but in case of nitrate inhibition, it was reversed than control. $Chlorophyll-{\alpha}$ was declined in treatment column water by 30% where it was 20% in control column water. Actibacter and Salegentibacter group were detectable in the calcium-peroxide-treated sediment; in contrary, no detectable community ware found in control sediment. Both phylogenetic groups are closely related to marine microflora. Conclusions: This study emphasizes the importance of calcium peroxide as an oxygen release material. Interaction with peroxide proved to be enhancing the formation of microbial community that are beneficial for biodegradation and spontaneity of nutrient attenuation into overlying water.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2016년도 춘계학술대회
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• pp.130-131
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• 2016

Although many metals contaminated sediment from coastal area contain both anionic and cationic heavy metals, the current remediation technologies are not effective for stabilize heavy metals of both anionic and cationic elements from contaminated coastal region. the present work investigated the efficiency and mechanism of immobilization of Fe, Zn, Cr, Cu, Pb and Cd metal solutions in modified zeolite based biostimulant ball. Biostimulant ball containing acetate, nitrate and sulphate which are enhance the activity of marine microorganisms and it can act as electron donors and electron acceptors. Modified zeolite and chelating agent is greatly enhance the metal stabilization due to increased immobility of the analysed metals. The XRD, FT-IR and SEM of modified zeolite which cheating agents containing heavy metals were investigated. The results indicated that heavy metals could be effectively immobilized in modified zeolite and chelating agents in BSB added sediment. The immobilization of heavy metals in modified zeolite and chelating agents along with BSB could be due to stabilize of heavy metal cations. Immobilization of heavy metals using BSB with modified zeolite and chelating agent has lower cost effect and enhance the sediment quality.

• Ocean and Polar Research
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• 제25권1호
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• pp.21-30
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• 2003

Seasonal fluctuations of physico-chemical and biological aspects of the environment were studied in Vladivostok harbour (Golden Horn Bay, the East Sea/Sea of Japan). The benthic community structure was described with a focus on size-spectra (bacteria, meio- and macrofauna) related with the chemical environment and chemical fluxes in sediment and to reveal their possible ecological role in the process of bioremediation of the environment. Samples from two sites with different concentrations of heavy metals (Fe, Zn, Cu, Pb, Mn, Cr, Ni Cd, Co) and petroleum hydrocarbon were assessed by a number of methods. These included plate counts of culturable bacteria, observation through a scanning electron (SEM) and transmission electron microscope (TEM). These approaches were complemented with microscopic assessments of the diversity of the benthic community. The specific communities had a limited number of species, tolerant to abnormally high levels of toxic compounds. The dominant species were presented by several sho.1-lived small polychaetes (Capitella capitata) and nematodes (Oncholaimium ramosum). The highest population density was recorded in microbenthos, in various diatoms, various physiological groups of bacteria which participate in biomineralization: marine heterotrophic bacteria, which oxidized oil, black oil in addition to groups resistant to heavy metals. They have the entire set of mechanisms for neutralizing the negative effect of those compounds, forming the detrital food web and biogeochemical circulation of material in sediments, which results in the biological self-recycling of sea basins. Macro- and meiobenthic organisms were more sensitive to a greater extent of $H_2S$ and petroleum hydrocarbons than to metal content, but the within-site rankings were the same as those achieved for microbiological analyses.

• 생명과학회지
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• 제21권11호
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• pp.1599-1606
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• 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.

• 생명과학회지
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• 제28권4호
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• pp.483-487
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• 2018

사이퍼메트린은 피레스로이드 계열 살충제로서 오랫동안 농업과 가정에서 이용되어 왔으며 그들의 잔여 성분과 독성에 대한 경각심이 고취되고 있다. 부산 인근의 해안에서 분리된 Cellulophaga lytica DAU203 균주가 사이퍼메트린의 생물학적 분해 활성을 나타내었다. DAU203 균주는 최소 배지에서 유일 탄소원으로 사이퍼메트린을 첨가하였을 때, 이를 분해하여 탄소원으로 활용 하였다. 반응표면분석법을 통하여 DAU203 균주의 사이퍼메트린 분해를 위한 최적 조건을 탐색하였다. 온도, pH와 yeast extract 첨가 농도와 같은 인자가 분해 활성에 영향을 미치는 것으로 분석 되었고, 각각의 최적 값은 $33.4^{\circ}C$, pH 7.7와 2.4%(w/v)이다. 최적 조건에서 DAU203 균주는 5일 동안 대략 83.7%의 사이퍼메트린을 분해하였다. 본 연구는 미생물 중에서 잘 연구되지 않은 해양 미생물에 대한 활용 가능성을 증가시켰다고 판단된다.