• Title, Summary, Keyword: Biostimulation

Search Result 48, Processing Time 0.033 seconds

Bioremediation of Diesel-Contaminated Soils by Natural Attenuation, Biostimulation and Bioaugmentation Employing Rhodococcus sp. EH831 (Natural attenuation, biostimulation 및 Rhodococcus sp. EH831을 이용한 bioaugmentation에 의한 디젤 오염 토양의 정화)

  • Lee, Eun-Hee;Kang, Yeon-Sil;Cho, Kyung-Suk
    • Microbiology and Biotechnology Letters
    • /
    • v.39 no.1
    • /
    • pp.86-92
    • /
    • 2011
  • Three bioremediation methods, natural attenuation (NA), biostimulation (BS) and bioaugmentation (BA) were applied to remediate diesel-contaminated soil, with their remediation efficiencies and soil microbial activities compared both with and without surfactant (Tween 80). BA treatment employing Rhodococcus sp. EH831 was the most effective for the remediation of diesel-contaminated soil at initial remediation stage. On the addition of surfactant, no significant effect on the remediation performance was observed. A negative correlation was found between the dehydrogenase activity (DHA) and residual concentration of total petroleum hydrocarbons (TPHs) at below 20,000 mg-$TPHs{\cdot}kg$-dry $soil^{-1}$, as follows: DHA (${\mu}g$-TPF(Triphenylformazan)${\cdot}g$-dry $soil^{-1}\;d^{-1}$) = -0.02 ${\times}$ TPHs concentration (mg-$TPHs{\cdot}kg$-dry $soil^{-1}$) + 425.76 (2500 ${\leq}$ TPHs concentration ${\leq}$ 20000, p < 0.01).

Effects of Low Incident Energy Levels of Infrared Laser Irradiation on Healing of Infected Open Skin Wounds in Rats (백서 연조직의 감염창상에 대한 저출력레이저조사시 치유효과에 관한 실험적 연구)

  • Phil-Yeon Lee;Ki-Suk Kim
    • Journal of Oral Medicine and Pain
    • /
    • v.17 no.2
    • /
    • pp.109-117
    • /
    • 1992
  • 저출력레이저는 인체조직에 biostimulation effects를 가지므로 구강주위에 발생하는 여려가지 질병에 대한 저출력레이저광의 효과에 관하여 많은 연구가 시도되고 있으며 또한 치료에 응용되고 있다. 감염창상에 저출력레이저 조사시 조직치유의 기전이 세균 성장에 의한 조직손상보다 주위 정상조직의 biostimulation effects가 우세하기 때문이라는 가설을 확인하고저 본 연구를 시행하였다. 백서 7마리를 레이저 조사군과 대조군으로 나누어 감염창상의 면적차이를 비교하여 다음고 같은 결론을 얻었다. 1. 저출력레이저 조사군에서 창상수축율이 현저히 높았다. 2. 부종의 빈도는 저출력레이저 조사시 뚜렷하게 감소하였다. 위의 사실로 보아 저출력레이저 조사시 감염창상의 치유촉진은 주위 정상조직의 biostimulation effect가 세균증식에 의한 조직의 손상보다 우세하기 때문이라는 가설을 확인할 수 있었다.

  • PDF

Single Well Push-Pull Test를 이용한 TCE 오염 지하수의 In-Situ Bioremediation 타당성조사

  • Kim, Yeong;Istok, Jonnathan;Semprini, Lewis
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
    • /
    • /
    • pp.188-191
    • /
    • 2003
  • Sing]e-well-push-pull tests were developed for use in assessing the feasibility of in-situ aerobic cometabolism of chlorinated aliphatic hydrocarbons (CAHs). The series includes Transport tests, Biostimulation tests, and Activity tests. Transport tests are conducted to evaluate the mobility of solutes used in subsequent tests. These included bromide or chloride (conservative tracers), propane (growth substrate), ethylene, propylene (CAH surrogates), dissolved oxygen (electron acceptor) and nitrate (a minor nutrient). Tests were conducted at an experimental well field of Oregon State University. At this site, extraction phase breakthrough curves for all solutes were similar, indicating apparent conservative transport of the dissolved gases and nitrate prior to biostimulation. Biostimulation tests were conducted to stimulate propane-utilizing activity of indigenous microorganisms and consisted of sequential injections of site groundwater containing dissolved propane and oxygen. Biostimulation was detected by the increase in rates of propane and oxygen utilization after each injection. Activity tests were conducted to quantify rates of substrate utilization and to confirm that CAH-transforming activity had been stimulated. In particular, the transformation of injected CAH surrogates ethylene and propylene to the cometabolic byproducts ethylene oxide and propylene oxide provided evidence that activity of the monooxygenase enzyme system, responsible for aerobic cometabolic transformations of CAHs had been stimulated. Estimated zero-order transformation rates decreased in the order propane > ethylene > propylene. The series of push-pu3l tests developed and field tested in this study should prove useful for conducting rapid, low-cost feasibility assessments for in situ aerobic cometabolism of CAHs.

  • PDF

현장 Single Well Push-Pull 실험을 통한 탈질산화반응 각 단계의 반응속도 측정

  • Yeong, Kim;Jin Hun, Kim;Bong Ho, Son;Seong Uk, Eo
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
    • /
    • /
    • pp.77-82
    • /
    • 2004
  • Quantifying rates of microbial processes under subsurface conditions is difficult, and is most commonly approximated by laboratory studies using aquifer materials. In this study a single-well, 'push-pull' test method is adapted for the in situ determination of denitrification rates in groundwater aquifers. The rates of stepwise reduction of nitrate to nitrite, nitrous oxide, and molecular nitrogen were determined by performing a series of push-pull tests at an experimental well field of Korea University. A single Transport Test, one Biostimulation Test, and four Activity Tests were conducted for this study. Transport tests are conducted to evaluate the mobility of solutes used in subsequent tests. These included bromide (a conservative tracer), fumarate (a carbon and/or source), and nitrate (an electron acceptor). At this site, extraction phase breakthrough curves for all solutes were similar, indicating apparent conservative transport of the solutes prior to biostimulation. Biostimulation tests were conducted to stimulate the activity of indigenous heterotrophic denitrifyinc microorganisms. Biostimulation was detected by the simultaneous production of carbon dioxide and nitrite after each injection. Activity tests were conducted to quantify rates of nitrate, nitrite, and nitrous oxide reduction. Estimated zero-order degradation rates decreased in the order nitrate '||'&'||'gt; nitrite '||'&'||'gt; nitrous oxide. The series of push-pull tests developed and field tested in this study should prove useful for conducting rapid, low-cost feasibi1ity assessments for in situ denitrification in nitrate-contaminated aquifers.

  • PDF

Effects of Low Incident Energy Levels of Infrared Laser Irradiation on the Proliferation of Candida Albicans Part I : A Long Term Study according to Pulse Type

  • Sam-Kun Kim;Phil-Yeon Lee;Ki-Suk Kim
    • Journal of Oral Medicine and Pain
    • /
    • v.19 no.1
    • /
    • pp.9-15
    • /
    • 1994
  • This experiment was performed to confirm the hypothesis that LLLT had biostimulation effect for all kinds of cells and there would be differences in the growth of cells among different types of pulsed laser. 360 samples were used in this study. The samples were randomly divided in 6 groups according to the pulse type : quasi continuous type (CW), pulse 1(P1), pulse 7(P7), pulse 9(P9), pulse 15(P15) and shame-irradiated control(Co) groups. Energy fluences of all experimental groups, P1, P7, P9, P15 and CW were 2.12, 2.12, 6.37, 57.32 and 31.85 mj/cm2 respectively. All samples were irradiated for every 1 minute at 0, 12, 24, 36, 48 and 60 hours. Ten samples of each group were sacrificed at 0 and every 12 hours and then the optical density of all samples was measured with the spectrophotometer. As a result, some types of pulses showed significant differences among groups. The increase of cells were markedly stimulated with laser irradiation in P7 and P9 groups, while inhibited in CW, P1, and P15 groups compared with control group. It is therefore, suggested that specific laser pulse should be recommanded to have the biostimulation effects on the specific tissue or cells, although the biostimulation effect is does dependant.

  • PDF

Monitoring of Microbial Diversity and Activity During Bioremediation of Crude Oil-Contaminated Soil with Different Treatments

  • Baek, Kyung-Hwa;Yoon, Byung-Dae;Kim, Byung-Hyuk;Cho, Dae-Hyun;Lee, In-Sook;Oh, Hee-Mock;Kim, Hee-Sik
    • Journal of Microbiology and Biotechnology
    • /
    • v.17 no.1
    • /
    • pp.67-73
    • /
    • 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.

SVE & Bioventing Techniques for the Treatment of Hydrocarbon (SVE와 Bioventing 기술을 이용한 유류 오염토양의 복원)

  • 김무훈;강순기;조미영;정우성;박덕신
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
    • /
    • /
    • pp.137-140
    • /
    • 2000
  • The purpose of this study is to see the effect of SVE (Soil Vapor Extraction) and Bioventing (biostimulation) hydrocarbon contaminated areas. The removal rate of VOC for three weeks were 17.43 kg on 3.6 ㎥/hr at steady-state. In the application of Bioventing, every flow rate were tested, and it was found that 4.0 ㎥/hr were adequate for best control of the system. At this stage, the addition of microbial agent accelerated the biodegradation of the hydrocarbon.

  • PDF

토양의 자연정화능과 다기능성 Colloidal Gas Aphron을 이용한 지하 환경에서의 BTEX 처리기술 개발

  • 박주영;남경필
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
    • /
    • /
    • pp.269-272
    • /
    • 2004
  • The use of colloidal gas aphron (CGA), as an external oxygen carrier, provides a promising alternative to promote aerobic bioremediation of BTEX in the subsurface environment. CGA is a stable bubble supported by three surfactant layers and can supply oxygen below the soil surface uniformly due to its plug-flow characteristic. Since CGA has a hydrophobic layer that can act as a partitioning medium for hydrophobic contaminants it is known to facilitate desorption of soil-sorbed contaminants. In addition, bioaugmentation and biostimulation are possibly achieved by using CGA when generated from a solution containing BTEX-degrading microorganisms and appropriate nutrients. In this study, we presented the physico-chemical characteristics of CGA generated from a solution composed of microorganisms and nutrients. The applicability of CGA as an in situ aerobic bioremediation technology of BTEX will be further evaluated.

  • PDF

유류오염토양 정화를 위한 생물활성 촉진방법의 평가

  • Kim Jong-Ha;Kim Tae-Seung;Yun Jeong-Gi;Kim Hyeok
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
    • /
    • /
    • pp.211-214
    • /
    • 2005
  • Bench-scale experiments conducted to evaluation of the biostimulation and bioaugmentation techniques in treatment of petroleum contaminated soil. The soil bioreactors were operated for a 52 day-period. PDB population in the stimulated treatments increased from $7{\times}10^4MPN/g$ soil in zero day to $7{\times}10^7MPN/g$ soil after 23 days. However, despite the initially higher PDB population in the augmented treatments, it was decreased PDB population with respect to time. The average biodegradation rate in the augmented treatments were greater than of the stimulated treatment in the early stage, but the average biodegradation rate in the latter stage were calculated $3{\sim}5mg/kg-day$ in the augmented treatments and 10.38mg/kg-day in the stimulated treatments. The TPH removal rate was calculated $20{\sim}30%$ in the augmented treatments and 53% in the stimulated treatments.

  • PDF