scholarly journals On Environmental Biotechnology of Bioremediation

2021 ◽  
Vol 5 (2) ◽  
pp. 3-8
Author(s):  
Ji-Dong Gu ◽  
Keyword(s):  
Environmental Biotechnology ◽  
Degradation Pathway ◽  
Environmental Chemicals ◽  
Contaminated Sites ◽  
Biochemical Reactions ◽  
Additional Information ◽  
Successful Attempt ◽  
Metabolic Products ◽  
A Site ◽  
Biochemical Degradation

Environmental biotechnology (EB) can play positive and an important role in detoxifying and eliminating pollutants, and cleaning up the contaminated sites of ecosystems, but the development of any EB is based largely on the scientific knowledge and results of (micro)biology and chemistry, and then application mainly on engineering and management. Biodegradation and bioremediation by definition are different in meaning and, as a result, they must be treated differently. On the fundamental basis, the biochemical reactions and the biochemical degradation pathway of any targeted toxicant concerned are basic information before the degradability of the selective pollutant by a microorganism can be claimed. Bioremediation becomes feasible for implementation with the knowledge of the biochemical reactions by the biological agent coupling with the engineering and management to achieve a successful attempt at a site. Though the degradability by a microorganism can be achieved in laboratory condition, the cleaning up of the pollutant at any site needs additional information and knowledge of the physical, chemical and ecological characteristics of the site to allow any success to be achieved. The broad EB can include utilization of pure and selective microorganisms, the biochemical reactions by either pure or mixed culture, enzymes, and metabolic products of microorganisms. In addition, microorganisms may also work in the form of biofilm to carry out the function to detoxify the toxic environmental chemicals. In addition to microorganisms, plants can play an important role in phytoremediation. Overall, environmental biotechnology needs at least three steps to prove its effectiveness from concept testing in laboratory, establishment of the mechanisms involved, workability in complex system and ecosystems, and lastly the implementation and practice on site. A laboratory success on degradation cannot be quickly and simply treated as a claim of EB for bioremediation for application.

scholarly journals A meta-analysis of published semivariograms to determine sample size requirements for assessment of heavy metal concentrations at contaminated sites

Soil Research ◽  
2019 ◽  
Vol 57 (4) ◽  
pp. 311 ◽  
Author(s):  
L. E. Pozza ◽  
T. F. A. Bishop
Keyword(s):  
Sample Size ◽  
Meta Analysis ◽  
Contaminated Sites ◽  
Metal Concentrations ◽  
Second Stage ◽  
Guideline Value ◽  
Guideline Values ◽  
The Mean ◽  
A Site ◽  
Specific Metal

Soil contamination poses substantial risks to human and ecosystem health, justifying the need for accurate delineation and remediation of contaminated sites. The number of soil samples collected at a site during assessment is limited by cost and time available for assessment, increasing the potential for misclassification due to insufficient samples. Using distributions of heavy metals sourced from semivariograms provided in published studies, the first stage of this study sought to determine how many samples were required for the confidence interval around the mean to be above or below the Australian guideline value for each specific metal and study. Estimated sample size for assessing mean contamination across a site ranged from two to four samples; however, some distributions possessed a higher amount of variation and therefore required more samples. The second stage of the investigation explored sample size requirements for mapping contaminated sites. Unconditional Gaussian simulations created from published semivariograms were sampled using 15 different sample sizes, and the samples used to obtain predictions of the simulated distributions. For each sample, observed (simulated) and predicted (kriged) metal concentrations were classed as being below or exceeding the guideline values and compared through quantification of the number of misclassifications that occurred. When mapping a site of 5 km2 or less, uncertainty and misclassification decreased with increasing sample size, stabilising at around 200 samples; however, the lowest uncertainty occurred at around 500 samples. The study acknowledges this may be unrealistic and economically inefficient, so in addition to these findings it is worth exploring improvement in other areas of investigation, such as in the detection and mapping stages.

Degradation of methamidophos by Hyphomicrobium species MAP-1 and the biochemical degradation pathway

2009 ◽  
Vol 21 (4) ◽  
pp. 513-523 ◽  
Author(s):  
Li Wang ◽  
Yang Wen ◽  
Xinqing Guo ◽  
Guangli Wang ◽  
Shunpeng Li ◽  
...  
Keyword(s):  
Degradation Pathway ◽  
Biochemical Degradation

Characterization of a novel cyfluthrin-degrading bacterial strain Brevibacterium aureum and its biochemical degradation pathway

2013 ◽  
Vol 132 ◽  
pp. 16-23 ◽  
Author(s):  
Shaohua Chen ◽  
Yi Hu Dong ◽  
Changqing Chang ◽  
Yinyue Deng ◽  
Xi Fen Zhang ◽  
...  
Keyword(s):  
Bacterial Strain ◽  
Degradation Pathway ◽  
Biochemical Degradation

Characterization of a novel β-cypermethrin-degrading Aspergillus niger YAT strain and the biochemical degradation pathway of β-cypermethrin

2015 ◽  
Vol 99 (19) ◽  
pp. 8187-8198 ◽  
Author(s):  
Weiqin Deng ◽  
Derong Lin ◽  
Kai Yao ◽  
Huaiyu Yuan ◽  
Zhilong Wang ◽  
...  
Keyword(s):  
Aspergillus Niger ◽  
Degradation Pathway ◽  
Biochemical Degradation

Biochemical degradation pathway of reactive blue 13 by Candida rugopelliculosa HXL-2

2011 ◽  
Vol 65 (1) ◽  
pp. 135-141 ◽  
Author(s):  
Xiuyan Liu ◽  
Ji Zhang ◽  
Jiandong Jiang ◽  
Rong Li ◽  
Zhengmiao Xie ◽  
...  
Keyword(s):  
Degradation Pathway ◽  
Biochemical Degradation

scholarly journals Degradation of 2,4,6-Trinitrotoluene (TNT): Involvement of Protocatechuate 3,4-Dioxygenase (P34O) in Buttiauxella sp. S19-1

Toxics ◽  
2021 ◽  
Vol 9 (10) ◽  
pp. 231
Author(s):  
Miao Xu ◽  
Dong Liu ◽  
Ping Sun ◽  
Yunuo Li ◽  
Ming Wu ◽  
...  
Keyword(s):  
Mutant Strain ◽  
Degradation Pathway ◽  
Degradation Efficiency ◽  
Bacterial Degradation ◽  
Contaminated Sites ◽  
Gas Chromatography Mass Spectrometry ◽  
Severe Damage ◽  
Gene Encoding ◽  
Key Enzyme ◽  
Intermediate Metabolite

Extensive use and disposal of 2,4,6-trinitrotoluene (TNT), a primary constituent of explosives, pollutes the environment and causes severe damage to human health. Complete mineralization of TNT via bacterial degradation has recently gained research interest as an effective method for the restoration of contaminated sites. Here, screening for TNT degradation by six selected bacteria revealed that Buttiauxella sp. S19-1, possesses the strongest degrading ability. Moreover, BuP34O (a gene encoding for protocatechuate 3,4-dioxygenase—P34O, a key enzyme in the β-ketoadipate pathway) was upregulated during TNT degradation. A knockout of BuP34O in S19-1 to generate S-M1 mutant strain caused a marked reduction in TNT degradation efficiency compared to S19-1. Additionally, the EM1 mutant strain (Escherichia coli DH5α transfected with BuP34O) showed higher degradation efficiency than DH5α. Gas chromatography mass spectrometry (GC-MS) analysis of TNT degradation by S19-1 revealed 4-amino-2,6-dinitrotolune (ADNT) as the intermediate metabolite of TNT. Furthermore, the recombinant protein P34O (rP34O) expressed the activity of 2.46 µmol/min·mg. Our findings present the first report on the involvement of P34O in bacterial degradation of TNT and its metabolites, suggesting that P34O could catalyze downstream reactions in the TNT degradation pathway. In addition, the TNT-degrading ability of S19-1, a Gram-negative marine-derived bacterium, presents enormous potential for restoration of TNT-contaminated seas.

scholarly journals Methodologies for compiling national inventories of contaminated sites and conducting preliminary site screening

2013 ◽  
Vol 16 (1) ◽  
pp. 24-35
Keyword(s):  
State Of The Art ◽  
Contaminated Sites ◽  
Regulatory Environment ◽  
Pollution Potential ◽  
Specific Data ◽  
National Inventory ◽  
Data Gaps ◽  
A Site ◽  
Environmental Relevance

<p>Procedures for compiling a national inventory of contaminated sites must take into account the technical state-of-the-art in the area of subsurface contamination and restoration, the national and supranational regulatory environment, as well as the national administrative infrastructure. Within this framework, this paper proposes a methodology of building a national inventory of potentially contaminated sites, which is based on activities of environmental relevance to the subsurface, i.e. soil and groundwater. As a next step, a screening system was developed, capable of estimating pollution potential of each site, for variable amount of available site-specific data. Depending on the nature of site data (actual or estimated) and the screening outcome, a site can be (i) delisted, (ii) assigned to an inactive list of potentially contaminated sites (iii) recommended for further desktop study and site visit or, (iv) recommended for both further study and in situ sampling. The advantage of the proposed approach is the identification of potentially contaminated sites on the basis of financial records linking activities with enterprises, which are more readily accessible compared with environmental records. The feasibility of transitioning from activities to sites has been demonstrated elsewhere. The present paper describes how data gaps are addressed by the site screening methodology with the aid of an application to a randomly selected real site in Greece.</p>

Screening of a beta-cypermethrin-degrading bacterial strain Brevibacillus parabrevis BCP-09 and its biochemical degradation pathway

2018 ◽  
Vol 29 (6) ◽  
pp. 525-541 ◽  
Author(s):  
Jie Tang ◽  
Bo Liu ◽  
Ting-ting Chen ◽  
Kai Yao ◽  
Lin Zeng ◽  
...  
Keyword(s):  
Bacterial Strain ◽  
Degradation Pathway ◽  
Biochemical Degradation ◽  
Brevibacillus Parabrevis

Second Report on the Publication and Conservation of the Tomb of Ramesses III in the Valley of the Kings (KV 11)

2020 ◽  
Vol 56 (1) ◽  
pp. 213-244
Author(s):  
Anke Weber ◽  
Judith Bunbury ◽  
Klara Dietze ◽  
Willem Hovestreydt ◽  
Dora Petrova ◽  
...  
Keyword(s):  
Archaeological Survey ◽  
Site Management ◽  
Additional Information ◽  
Conservation Treatment ◽  
Current State ◽  
Field School ◽  
Heritage Site ◽  
A Site ◽  
Wall Decoration ◽  
Sedimentation Processes

The Ramesses III (KV 11) Publication and Conservation Project is currently developing a site management, conservation and publication strategy for the severely damaged tomb of pharaoh Ramesses III in order to prevent further deterioration and to preserve this cultural heritage site for future generations. Along with first urgent measures of conservation, a geo-archaeological survey of KV 11 and its surroundings, as well as a geomatic and photogrammetric survey of the tomb itself, were carried out. The detailed recording of the current state of the architecture and wall decoration allowed for further reconstruction of scenes and texts. Moreover, an archaeological sondage in the burial chamber revealed additional information about the ooding and sedimentation processes. A field school with students of Luxor University offered training in digital recording methods and epigraphy, geo-archaeological survey and mapping methodologies, and conservation treatment and assessment. The following article outlines preliminary results in the fields of geology, conservation, recording, reconstruction, and excavation.

scholarly journals Isolation and identification of a 2,3,7,8-Tetrachlorodibenzo-P-dioxin degrading strain and its biochemical degradation pathway

2021 ◽  
Author(s):  
Lina Qiu ◽  
Weiwei Zhang ◽  
Aijun Gong ◽  
Jiandi Li
Keyword(s):  
High Efficiency ◽  
Degradation Pathway ◽  
Order Kinetic ◽  
Isolation And Identification ◽  
Cultural Conditions ◽  
Order Kinetic Model ◽  
Tetrachlorodibenzo P Dioxin ◽  
Biochemical Degradation ◽  
Central Composite ◽  
18S Rdna Sequence

AbstractThis study aims to find a high-efficiency degradation strain which can biodegrade the 2,3,7,8-Tetrachlorodibenzo-P-dioxin (2,3,7,8-TCDD). In this paper, a new fungus strain was isolated from activated sludge of Dagu Drainage River in Tianjin which was able to degrade 2,3,7,8-TCDD in the medium. Based on its morphology and phylogenetic analysis of its 18S rDNA sequence, the strain was identified as Penicillium sp. QI-1. Response surface methodology using central composite rotatable design of cultural conditions was successfully employed for optimization resulting in 87.9 % degradation of 2,3,7,8-TCDD (1 µg/mL) within 6 days. The optimum condition for degrading 2,3,7,8-TCDD was at 31℃ and pH 7.4. The biodegradation process was fitted to a first-order kinetic model. The kinetic equation was Ct=0.939e− 0.133t and its half-life was 5.21d. The fungus strain degraded 2,3,7,8-TCDD to form intermediates, they were 4,5-Dichloro-1,2-benzoquinone, 4,5-Dichlorocatechol, 2-Hydrooxy-1,4-benzoquinone, 1,2,4-Trihydroxybenzene and β-ketoadipic acid. A novel degradation pathway for 2,3,7,8-TCDD was proposed based on analysis of these metabolites. The results suggest that Penicillium sp. QI-1 may be an ideal microorganism for biodegradation of the 2,3,7,8-TCDD-contaminated environments.

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