【導讀】厭氧污泥層)反應堆從后面的結(jié)合的厭氧的，減少的脫氯的細菌入粒狀淤渣。所有的三個反應堆是投放礦物媒介包含3到。57µMPCE，2毫升甲酸鹽，和。反應器，沒有接種，只產(chǎn)生三氯乙，平均43%的流出物氯乙。被測試在無接種體的無接種體不活躍顆粒的非生物防治。在隨著逐漸減少液壓傳動裝置。相反的，R2反應器，沒有接種微生物，只在相同的條件下將氯乙轉(zhuǎn)化成三氯乙。固定可以通過利用螢光素-標記抗體探測微生。物的發(fā)酵來證實。適當?shù)拇鎯吞幚?，?shù)量巨大的氯乙烯化合物是傳遍全世界。證明是缺氧狀態(tài)經(jīng)過減少的機制的脫氯作用。作用的氯乙烯，已經(jīng)有結(jié)論。免疫熒光顯微術(shù)在顆粒薄片的利用，可以表明這種細菌在粒狀污泥制造小集落。獲得，分別代表反應器的流入和流出。粒狀淤渣從添加PCE以及乙醇試劑達一年左右的實驗室UASB反應器中獲取。190nm的紫外線檢測。試樣和標準溶液用20μL10％的硫酸酸化至pH為。DCE的立體異構(gòu)組成由氣相色譜法確定。的正戊烷萃取，作為試樣的內(nèi)部標準。

　　

【正文】 be the dechlorinating strain of D. multivorans, since this bacterium would be expected to show quick proliferation, resulting in a large population, as seen in the test and R1 reactors. This was the case in an earlier experiment where a reactor similar to the R2 reactor accidentally became contaminated by D. multivorans. The bacterium spread throughout the granular sludge within days (data not shown). PCE removal increased linearly with increasing PCE loading of the test and R1 reactors, both inoculated with D. multivorans, indicating that no inhibitory effects were seen at any PCE loading rate tested. The slightly lower PCE removal rate of the test reactor was further seen as a slower adaptation capability when the HRT was lowered. This resulted in a temporary appearance of PCE and TCE in the effluent. In contrast, the dechlorinating performance of the R1 reactor did not change with changes in the HRT. This effect could be due to D. multivorans being present in lower cell numbers per unit of granules in the test reactor than in the R1 reactor, making the unsterile inoculated system more sensitive to changes in HRT. A total consumption of the formate added was seen for the R2 reactor, pared to only 39% consumption of the formate added to reactor R1. This indicates that formate was used by bacteria other than D. multivorans in the unsterile granular sludge. Formate was never detected in the effluent of the test reactor, and a lack of this electron donor is possible in this reactor. PCE dechlorination is an energyconserving process for D. multivorans, and therefore the lack of the electron donor might shorten the energy gain and result in a lower cell number than that observed when the formate supply is sufficient. The placement of the introduced bacteria observed in this study is in contrast to that in previous studies. Immobilization of the dechlorinating bacterium D. hafniense in sterile granules resulted in a like uniform growth of the anism, while immobilization of D. tiedjei in unsterile sludge resulted in the formation of microcolonies (1, 3). These results show that the placement of the introduced bacteria is controlled by individual factors within the specific system. Since the conditions for D. multivorans, for instance, regarding exposure to formate, in sterile granules will be different from those in active granules, differences in placement can be expected. In the present study, we showed for the first time that D. multivorans could be immobilized in granular sludge, where it enhanced the PCE dechlorination activity significantly. Furthermore, this incorporation of D. multivorans resulted in a change in product formation towards a pound (DCE) which is much more amenable to further conversion in aerobic aftertreatment than the original product (TCE). These results are of considerable significance to the bioremediation of PCEcontaminated aquifers. ACKNOWLEDGMENTS We thank Jacob Rasmussen for technical assistance. This research was supported by grants from the Commission of the European Communities, contract EV5VCT920239 (BIODEC project), and the Danish Technical Science Council (no. 950265728813). FOOTNOTES ? Corresponding author. Mailing address: Department of Environmental Science and Engineering, Technical University of Denmark, Building 113, DK2800 Lyngby, Denmark. Phone: 45 4525 1566. Fax: 45 4593 2850. Email: . REFERENCES , B. K., N. Christiansen, I. Mathrani, H. V. Hendriksen, A. J. L. Macario, and E. Conway de Macario. 1992. Introduction of a de novo bioremediation ability, aryl reductive dechlorination, into anaerobic granular sludge by inoculation of sludge with Desulfomonile tiedjei. Appl. Environ. Microbiol. 58:36773682[Abstract]. 2. Christiansen, N., and B. K. Ahring. 1996. 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