Bioremediation of PCB-contaminated shallow river sediments

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Bioremediation of PCB-contaminated shallow river sediments: The efficacy of biodegradation using individual bacterial strains and their consortia

 

Article Link:  https://www.sciencedirect.com/science/article/pii/S0045653517317721

 

Abstract:

Elimination of dangerous toxic and hydrophobic chlorinated aromatic compounds, mainly PCBs from the environment, is one of the most important aims of the environmental biotechnologies. In this work, biodegradation of an industrial mixture of PCBs (Delor 103, equivalent to Aroclor 1242) was performed using bacterial consortia composed of four bacterial strains isolated from the historically PCB-contaminated sediments and characterized as  Achromobacter xylosoxidans, Stenotrophomonas maltophilia, Ochrobactrum anthropi  and  Rhodococcus ruber. The objective of this research was to determine the biodegradation ability of the individual strains and artificially prepared consortia composed of two or three bacterial strains mentioned above. Based on the growth parameters, six consortia were constructed and inoculated into the historically contaminated sediment samples collected in the efflux canal of Chemko Strážske plant — the former producer of the industrial mixtures of PCBs. The efficacy of the biotreatment, namely bioaugmentation, was evaluated by determination of ecotoxicity of treated and non-treated sediments. The most effective consortia were those containing the strain  R.  ruber. In the combination with  A.  xylosoxidans, the biodegradation of the sum of the indicator congeners was 85% and in the combination with  S.  maltophilia  nearly 80%, with inocula applied in the ratio 1:1 in both cases. Consortium containing the strain  R.  ruber  and  S.  maltophilia  showed pronounced degradation of the highly chlorinated PCB congeners. Among the consortia composed of three bacterial strains, only that consisting of  O.  anthropi, R. ruber  and  A.  xylosoxidans  showed higher biodegradation (73%). All created consortia significally reduced the toxicity of the contaminated sediment.

 

I chose this article because of its relevance to our recent topics in class. It is an interesting examination of microbes involved in the breakdown of PCBs in river sediment.

 

Citation:  

Horvathorva, H., K. Laszlova, K. Dercova.  Bioremediation of PCB-contaminated shallow river sediments: The efficacy of biodegradation using individual bacterial strains and their consortia. 2018. Chemosphere 193:270-277.

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OMG JET FUEL EVERYWHERE SEND HELP

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This presentation chronicles the response to a jet fuel spill at the Fairbanks International Airport, highlighting elements such as microbial activity and impacts to human health.

 

Note: For the best experience, please view this presentation in Full Screen mode.

 

 

 

By Karen Biondich, Ben Hedges, Bayli Mohl, Courtney Hill, and Mark Velasco

Enhancing pesticide degradation using indigenous microorganisms

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Citation

Diaz, J. et al. Enhancing pesticide degradation using indigenous microorganisms isolated under high pesticide load in bioremediation systems with vermicomposts. 2016. Bioresource Technology. 214: 234-241.

 

Abstract

In biobed bioremediation systems (BBSs) with vermicomposts exposed to a high load of pesticides, 6 bacteria and 4 fungus strains were isolated, identified, and investigated to enhance the removal of pesticides. Three different mixtures of BBSs composed of vermicomposts made from greenhouse (GM), olive-mill (OM) and winery (WM) wastes were contaminated, inoculated, and incubated for one month (GMI, OMI and WMI). The inoculums maintenance was evaluated by DGGE and Q-PCR. Pesticides were monitored by HPLC-DAD. The highest bacterial and fungal abundance was observed in WMI and OMI respectively. In WMI, the consortia improved the removal of tebuconazole, metalaxyl, and oxyfluorfen by 1.6-, 3.8-, and 7.7-fold, respectively. The dissipation of oxyfluorfen was also accelerated in OMI, with less than 30% remaining after 30 d. One metabolite for metalaxyl and 4 for oxyfluorfen were identified by GC—MS. The isolates could be suitable to improve the efficiency of bioremediation systems.

 

Link

https://www.sciencedirect.com/science/article/pii/S0960852416306010

 

This paper shows some practical applications of microbes as bioremediators, exploring the processes of bioremediation in contaminated vericomposts. It explores ways of bioremediation of agricultural waster with microbes.

 

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Microbial ecology of denitrification in biological wastewater treatment

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Citation:  Lu, H., K. Chandran, and D. Stensel. Microbial ecology of denitification in biological wastewater treatment. 2014. Water Research. 64:237-254.

Find the article here.  If you can’t access the article through this link, you can log into ScienceDirect with you UA credentials to get the full article for free.

And I am attaching the PDF here just in case:  1-s2.0-S0043135414004886-main

 

Abstract:  Globally, denitrification is commonly employed in biological nitrogen removal processes to enhance water quality. However, substantial knowledge gaps remain concerning the overall community structure, population dynamics and metabolism of different organic carbon sources. This systematic review provides a summary of current findings pertaining to the microbial ecology of denitrification in biological wastewater treatment processes. DNA fingerprinting-based analysis has revealed a high level of microbial diversity in denitrification reactors and highlighted the impacts of carbon sources in determining overall denitrifying community composition. Stable isotope probing, fluorescence  in situ  hybridization, microarrays and meta-omics further link community structure with function by identifying the functional populations and their gene regulatory patterns at the transcriptional and translational levels. This review stresses the need to integrate microbial ecology information into conventional denitrification design and operation at full-scale. Some emerging questions, from physiological mechanisms to practical solutions, for example, eliminating nitrous oxide emissions and supplementing more sustainable carbon sources than methanol, are also discussed. A combination of high-throughput approaches is next in line for thorough assessment of wastewater denitrifying community structure and function. Though denitrification is used as an example here, this synergy between microbial ecology and process engineering is applicable to other biological wastewater treatment processes.

 

 

This article sparked my interest mostly because we just finished talking about the nitrogen cycle, and this is a great practical example of denitrification in biological wastewater treatment.

 

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Group Thinglink project – Microbial Communities

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This project is an analysis of the microbial communities surrounding the Alaska Native Medical Center in Anchorage, Alaska, including plant root microbiomes, urban waterways, the built environment within the hospital, soils, and clouds.

 

Created by: Karen Biondich, Benjamin Hedges, Courtney Hill, Bayli Mohl, Mark Velasco

The microbiome of urban waters – Non-technical Summary

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The microbiome of urban waters – Non-technical Summary

With more than half the world’s population living in or near urban centers, urban waters are an important point of interaction between humans and the natural environment. Urban waterways include sewers, storm drains, and urban lakes and streams. The identity and characteristics of the microorganisms that are living in these waterways can be a good indicator of pollutions, possible risks to human health, and any other ways that humans could be affecting the natural environment. Microbes can act as indicators of how humans are affect the environment. The presence of microbes that are harmful to humans can be indicators of risks to human health, such as outbreaks of certain diseases in a population. Other microbes that are commonly linked to human waste can be an indicator of fecal contamination. Microbes linked to the breakdown of certain chemicals can indicate other forms of pollution in the water.

 

Microbes gather in urban waterways through several ways. Soil, building, and other surfaces that humans come into contact with can transport microbes to waterways through runoff, while the release of sewage and storm drains water into other waterways can also introduce new microbes. As these urban waterways combine, these microbes can eventually be transported to natural streams or oceans. The presence of the foreign microbes can have negative impact on the natural environment, such as impact the natural food web, which can wreak havoc on local organisms.

 

Citation:  MacLellen, Sandra, J. Fisher, and R. Newton. The microbiome of urban waters. 2015. International Microbiology. 18:141-149.

Article Link:  https://revistes.iec.cat/index.php/IM/article/viewFile/140617/139602

 

The microbiome of urban waters – Technical Summary

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The microbiome of urban waters – Technical Summary

With more than half of the world’s population living in or near urban centers, urban waters are an important interaction point between humans and the natural environment. Urban waterways include sewers, storm drains, and urban lakes and streams whose microbiome can be an indicator of pollutants, human health risks, and any other ways in which humans are affecting the natural environment. These indicators include many different microbes. The  presence of certain microbes, such as human pathogens, can indicate human health risks. The human microbiome is used as a tracer of fecal contamination in these waterways. Other microbes can indicate what types of pollution might be present, such as microbes associated with specific chemicals or human waste.

Microbes accumulate in urban waterways through runoff from soils and the built environment, release of stormwater or sewage into another waterway, and transfer from humans. As these urban waterways combine with natural waters, such as streams and oceans, non-indigenous microbes are released into those environments. These non-indigenous microbes can alter the environmental conditions, such as the natural food web, and have a potentially hazardous impact on the natural environment.

 

Citation:  MacLellen, Sandra, J. Fisher, and R. Newton. The microbiome of urban waters. 2015. International Microbiology. 18:141-149.

Article Link:  https://revistes.iec.cat/index.php/IM/article/viewFile/140617/139602

 

The Microbial Engines That Drive the Earths Biogeochemical Cycles

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Citation:

Falkowski, P., T. Fenchel, and E. Delong. 2008. The microbial engines that drive the earths biogeochemical cycles. Science. 302, 5879:1034-1039.

 

Full article: https://science.sciencemag.org/content/320/5879/1034.full

 

Abstract:

Virtually all nonequilibrium electron transfers on Earth are driven by a set of nanobiological machines composed largely of multimeric protein complexes associated with a small number of prosthetic groups. These machines evolved exclusively in microbes early in our planet’s history yet, despite their antiquity, are highly conserved. Hence, although there is enormous genetic diversity in nature, there remains a relatively stable set of core genes coding for the major redox reactions essential for life and biogeochemical cycles. These genes created and coevolved with biogeochemical cycles and were passed from microbe to microbe primarily by horizontal gene transfer. A major challenge in the coming decades is to understand how these machines evolved, how they work, and the processes that control their activity on both molecular and planetary scales.

 

I chose this article because of the great explanations of microbial involvement in biogeochemical cycling on a chemical basis, touches on the evolution of these processes, and explains how they control activity on different levels.

 

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Assignment 1: Introduction

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Hey everyone!

My name is Karen and I am majoring in biology with a concentration in physiology. I am currently a CNA working in an assisted living home and planning on going to grad school somewhere warm (aka not Alaska) to become a PA. I have been looking forward to this class since I first heard of it, especially the writing intensive part! I have worked in environmental education in the past and I have run several blogs. I have a great interest in making scientific concepts more understandable to the general public while not losing any important content or ideas, and I think that combining traditional scientific writing with more creative ideas is a great way to achieve that.

 

Here is my haiku from class:

Decomposition

Energy cycles through all

Life into new life

 

Starvation Gulch 2016