혐기성 퇴적물에서 토착미생물에 의한 6가 크롬의 환원
Cr(VI) Reduction by Indigenous Bacteria in Anaerobie Sediment
2
조회
0
다운로드
3
인용
0
참고문헌
키워드
초록
6가 크롬은 중성의 pH에서 용해도가 높은 형태로 존재하기 때문에 오염원들로부터 주위 환경에 쉽게 누출될 수 있다. 크롬에 내성을 가진 토착미생물은 6가 크롬을 독성과 용해도가 낮은 3가 크롬으로 환원시킬 수 있다. 본 연구에서는 염색공장 지역 인근의 크롬으로 오염된 퇴적물에서 토착미생물을 분리하여, 혐기성 환경에서 6가 크롬의 해독작용에 대한 토착 미생물의 영향에 대해서 연구하였다. 실험 결과 용존된 6가 크롬의 약 99%가 240시간 안에 환원되었다. 단백질 함량의 변화로부터, 6가 크롬의 환원에 기여하는 토착미생물들은 6가 크롬이 주입된 후 적절한 적응 시간이 필요한 것으로 나타났다. 또한 배지에 적절한 탄소원을 공급하면 6가 크롬 환원의 효율성이 크게 증가하는 것으로 나타났으며, pH 증가에 따라 6가 크롬의 제거 속도가 감소하는 결과를 나타내었다. 크롬으로 오염된 퇴적물 내의 토착미생물은 퇴적물 내에서 6가 크롬을 환원시킬 수 있고 이러한 토착미생물에 의한 크롬의 환원은 오염된 퇴적물의 자연저감을 유도하여 생태계로의 크롬 이동을 방지할 수 있다.
Abstract
Hexavalent Cr is easily released to surrounding environments from contamination sources because Cr(VI) exists as soluble forms at neutral pH. Indigenous bacteria which showed resistivity against the high level of chromium may convert Cr(VI) to Cr(III) which is less toxic and less soluble. In this study, indigenous bacteria were isolated from Cr-contaminated sediments in the area of pigment manufacturing factories. The effects of the indigenous bacteria on Cr(VI) reduction were investigated under anaerobic condition. From the onset of the experiment, 99% of dissolved Cr(VI) was rapidly reduced within 240 hours. The variation of protein indicates that the indigenous bacteria reduce Cr(VI) need to the adaptation period for addition of Cr(VI). The addition of lactate, glucose and acetate to the bacteria improved the efficiency of Cr(VI) reduction. The removal rate of Cr(VI) decreased with an increase in solution pH. The indigenous bacteria can reduce Cr(VI) in contaminated sediments and this ability of indigenous bacteria has a potential for in situ containment of Cr in Cr-contaminated environments.
참고문헌 (23)
- Arias, "reduction by sulfidogenic and nonsulfidogenic microbial consortia", 69 (2003)
- Cheung, "Reduction of chromate by an enrichment consortium and an isolate of marine sulfate-reducing bacteria", 52, pp.1523~1529 (2003)
- E.M, "Hexavalent chromium reduction by Bacillus sp. in a packed-bed bioreactor", 31, pp.1446~51 (1997)
- Greenberg, "Standard Methods for the Examination of Water and Wastewater", pp.59~126 (1998)
- Daniels, "Methods for General and Molecular Bacteriology American Society for Microbiology", pp.512~554 (1994)
- Ehrlich, "2nd ed. Revised and Expanded", pp. 449-513. (1990)
- Fein, "Nonmetabolic reduction of Cr by bacterial surfaces under nutrient-absent conditions", boya 19(v), pp.369~382 (2002)
- Francis, "Dissimilatory metal reduction by the facultative anaerobe Pantoea agglomerans SP1", 66, pp.543~548 (2000)
- Gadd G.M, "Microbial treatment of metal pollution-a working biotechnology Trends in Biotechnology", 11, pp.353~359 (1993)
- Guha, H, "Kinetics of chromium reduction by a type strain Shewanella alga under different growth conditions", 115, pp.209~218 (2001)
- Kashefi, K, "Reduction of Fe(III), Mn(IV), and toxic metals at 100 ? by Pyrobaculum islandicum", 66, pp.1050~1056 (2000)
- Bonet, "Chromate reduction by resting cells of Agrobacterium radiobacter EPS-916", 59, pp.3516~3518 (1993)
- D.R, "Reduction of chromate by Desulfovibrio vulgaris and its C3 cytochrome", 60, pp.726~728 (1994)
- Michel, "Enzymatic reduction of chromate", 55, pp.95~100 (2001)
- A.Y, "Sulfur disproportionation by the facultative anaerobe Pantoea agglomerans SP1 as a mechanism for chromium", 19, pp.121~132 (2002)
- Persaud, "Development of Provinicial Sediment Quality Guidelines. Ontario Ministry of the Environment", pp.19~ (1989)
- Postgate, "The sulphate-reducing bacteria", pp.208~ (1984), 2nd ed. Cambridge University Press
- Shen, "Biological reduction of chromium by E. coli. Journal of Environmental Engneering", 120, pp.560~572 (1994)
- Tebo, "Sulfate-reducing bacterium grows with Cr(VI), U(VI), Mn(IV), and Fe(III) as electron acceptors", 162 (1998)
- US EPA, "Toxicological Review of Hexavalent Chromium" (1998)
- Wang Y.T, "Bacterial reduction of hexavalent chromium" (1995)
- A, "Carcinogenicity of chromium compounds Chromium in the Natural and Human Environments. John Wiley and Sons", pp.514~530 (1988)
- Zhao, "Column sorption of Cr", 20, pp.603~606 (1997)