國立虎尾科技大學 |

Biodegradation of 1,4-Dioxane in Co-Contaminant Mixtures.

紀錄類型:	書目-語言資料,手稿 : Monograph/item
正題名/作者:	Biodegradation of 1,4-Dioxane in Co-Contaminant Mixtures./
作者:	Zhang, Shu.
面頁冊數:	1 online resource (108 pages)
附註:	Source: Dissertation Abstracts International, Volume: 78-09(E), Section: B.
Contained By:	Dissertation Abstracts International78-09B(E).
標題:	Environmental engineering. -
電子資源:	click for full text (PQDT)
ISBN:	9781369756869

Biodegradation of 1,4-Dioxane in Co-Contaminant Mixtures.
Zhang, Shu.

Biodegradation of 1,4-Dioxane in Co-Contaminant Mixtures. - 1 online resource (108 pages)

Source: Dissertation Abstracts International, Volume: 78-09(E), Section: B.

Thesis (Ph.D.)--University of California, Los Angeles, 2017.

Includes bibliographical references

Bioremediation is a promising technology to degrade or detoxify various organic and inorganic compounds in polluted environments by using microbiological activity, but it is sensitive to biogeochemical conditions as well as co-occuring compounds at impacted sites. This study focused on biodegradation of 1,4-dioxane, which is a carcinogen and an emerging water contaminant. 1,4-Dioxane was utilized as a stabilizer of chlorinated solvents, such as 1,1,1-trichloroethane (TCA); and it has been found widespread in groundwater. Many US states are implementing lower regulatory advisory levels based on the toxicity profile of 1,4-dioxane and the potential public health risks. However, the unique chemical properties of 1,4-dioxane, such as high water solubility, low Henry's law constant, and importantly, the co-occurrence with chlorinated solvents and other contaminants, increase the challenges to efficiently cleanup 1,4-dioxane contaminations. The objectives of this research were to measure and model the effects of chlorinated solvents on 1,4-dioxane metabolic biodegradation by laboratory pure cultures, elucidate the mechanisms of the inhibition, and test the effects of mixtures of co-contaminants in samples collected from actual 1,4-dioxane contaminated sites. It was determined that individual solvents inhibited biodegradation of 1,4-dioxane in the following order: 1,1-dichloroethene (1,1-DCE) > cis-1,2-diochloroethene (cDCE) > trichloroethene (TCE) > 1,1,1-trichloroethane (TCA). The results confirmed that 1,1-DCE was the strongest inhibitor of 1,4-dioxane biodegradation, even in chlorinated ethene mixtures. The energy production was delayed, and the genes coding for catalytic enzymes, dioxane monooxygenase (dxmB) and alcohol dehydrogenase (aldH) were down regulated, in the presence of chlorinated solvents. These results will be useful to scientists in understanding the fundamentals of enzymatic processes that catalyze biological degradation of hazardous compounds, and to environmental engineers by providing quantitative data valuable for the development of in-situ bioremediation approaches for contaminant mixtures.

Electronic reproduction.
Ann Arbor, Mich. :
ProQuest,
2018

Mode of access: World Wide Web

ISBN: 9781369756869Subjects--Topical Terms:

557376
Environmental engineering.
Index Terms--Genre/Form:

554714
Electronic books.

Biodegradation of 1,4-Dioxane in Co-Contaminant Mixtures.
LDR:03349ntm a2200325Ki 4500 001 918790
005 20181106104111.5
006 m o u
007 cr mn||||a|a||
008 190606s2017 xx obm 000 0 eng d
020 $a 9781369756869
035 $a (MiAaPQ)AAI10276647
035 $a (MiAaPQ)ucla:15351
035 $a AAI10276647
040 $a MiAaPQ $b eng $c MiAaPQ $d NTU
100 1 $a Zhang, Shu. $3 1193210
245 1 0 $a Biodegradation of 1,4-Dioxane in Co-Contaminant Mixtures.
264 0 $c 2017
300 $a 1 online resource (108 pages)
336 $a text $b txt $2 rdacontent
337 $a computer $b c $2 rdamedia
338 $a online resource $b cr $2 rdacarrier
500 $a Source: Dissertation Abstracts International, Volume: 78-09(E), Section: B.
500 $a Adviser: Shaily Mahendra.
502 $a Thesis (Ph.D.)--University of California, Los Angeles, 2017.
504 $a Includes bibliographical references
520 $a Bioremediation is a promising technology to degrade or detoxify various organic and inorganic compounds in polluted environments by using microbiological activity, but it is sensitive to biogeochemical conditions as well as co-occuring compounds at impacted sites. This study focused on biodegradation of 1,4-dioxane, which is a carcinogen and an emerging water contaminant. 1,4-Dioxane was utilized as a stabilizer of chlorinated solvents, such as 1,1,1-trichloroethane (TCA); and it has been found widespread in groundwater. Many US states are implementing lower regulatory advisory levels based on the toxicity profile of 1,4-dioxane and the potential public health risks. However, the unique chemical properties of 1,4-dioxane, such as high water solubility, low Henry's law constant, and importantly, the co-occurrence with chlorinated solvents and other contaminants, increase the challenges to efficiently cleanup 1,4-dioxane contaminations. The objectives of this research were to measure and model the effects of chlorinated solvents on 1,4-dioxane metabolic biodegradation by laboratory pure cultures, elucidate the mechanisms of the inhibition, and test the effects of mixtures of co-contaminants in samples collected from actual 1,4-dioxane contaminated sites. It was determined that individual solvents inhibited biodegradation of 1,4-dioxane in the following order: 1,1-dichloroethene (1,1-DCE) > cis-1,2-diochloroethene (cDCE) > trichloroethene (TCE) > 1,1,1-trichloroethane (TCA). The results confirmed that 1,1-DCE was the strongest inhibitor of 1,4-dioxane biodegradation, even in chlorinated ethene mixtures. The energy production was delayed, and the genes coding for catalytic enzymes, dioxane monooxygenase (dxmB) and alcohol dehydrogenase (aldH) were down regulated, in the presence of chlorinated solvents. These results will be useful to scientists in understanding the fundamentals of enzymatic processes that catalyze biological degradation of hazardous compounds, and to environmental engineers by providing quantitative data valuable for the development of in-situ bioremediation approaches for contaminant mixtures.
533 $a Electronic reproduction. $b Ann Arbor, Mich. : $c ProQuest, $d 2018
538 $a Mode of access: World Wide Web
650 4 $a Environmental engineering. $3 557376
655 7 $a Electronic books. $2 local $3 554714
690 $a 0775
710 2 $a ProQuest Information and Learning Co. $3 1178819
710 2 $a University of California, Los Angeles. $b Civil Engineering 0300. $3 1187075
773 0 $t Dissertation Abstracts International $g 78-09B(E).
856 4 0 $u http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=10276647 $z click for full text (PQDT)