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  • 1.
    Anbalagan, Anbarasan
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    A passage to wastewater nutrient recovery units: Microalgal-Bacterial bioreactors2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    In recent years, the microalgal–bacterial process has been considered to be a very attractive engineering solution for wastewater treatment. However, it has not been widely studied in the context of conventional wastewater treatment design under Swedish conditions. The technology holds several advantages: as a CO2 sink, ability to withstand cold conditions, ability to grow under low light, fast settling without chemical precipitation, and reducing the loss of valuable nutrients (CO2, N2, N2O, PO4). The process also provides the option to be operated either as mainstream (treatment of municipal wastewater) or side stream (treatment of centrate from anaerobic digesters) to reduce the nutrient load of the wastewater. Furthermore, the application is not only limited to wastewater treatment; the biomass can be used to synthesise platform chemicals or biofuels and can be followed by recovery of ammonium and phosphate for use in agriculture.

    In the present study, the feasibility of applying the process in Swedish temperature and light conditions was investigated by implementing microalgae within the activated sludge process. In this context, the supporting operational and performance indicators (hydraulic retention time (HRT), sludge retention time (SRT) and nutrients removal) were evaluated to support naturally occurring consortia in photo-sequencing and continuous bioreactor configuration. Furthermore, CO2 uptake and light spectrum-mediated nutrient removal were investigated to reduce the impact on climate and the technical challenges associated with this type of system.

    The results identified effective retention times of 6 and 4 days (HRT = SRT) under limited lighting to reduce the electrical consumption. From the perspective of nitrogen removal, the process demands effective CO2 input either in the mainstream or side stream treatment. The incorporation of a vertical absorption column demonstrated effective CO2 mass transfer to support efficient nitrogen and phosphorus removal as a side stream treatment. However, the investigation of a continuous single-stage process as the mainstream showed a requirement for a lower SRT in comparison to semi-continuous operation due to faster settlability, regardless of inorganic carbon. Furthermore, the process showed an effective reduction of influent phosphorus and organic compounds (i.e. COD/TOC) load in the wastewater as a result of photosynthetic aeration. Most importantly, the operation was stable at the temperature equivalent of wastewater (12 and 13 ˚C), under different lighting (white, and red-blue wavelengths) and retention times (6 and 1.5 d HRT) with complete nitrification. Additionally, the biomass production was stable with faster settling properties without any physiochemical separation.

    The outcomes of this thesis on microalgal–bacterial nutrient removal demonstrates that (1) photosynthesis-based aeration at existing wastewater conditions under photo-sequential and continuous photobioreactor setup, (2) flocs with rapid settling characteristics at all studied retention times, (3) the possibility of increasing carbon supplementation to achieve higher carbon to nitrogen balance in the photobioreactor, and (4) most importantly, nitrification-based microalgal biomass uptake occurred at all spectral distributions, lower photosynthetic active radiation and existing wastewater conditions.

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  • 2.
    Bonaglia, Stefano
    et al.
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Rämö, Robert
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Marzocchi, Ugo
    Le Bouille, Léonie
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Leermakers, Martine
    Nascimento, Francisco J. A.
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Gunnarsson, Jonas S.
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Capping with activated carbon reduces nutrient fluxes, denitrification and meiofauna in contaminated sediments2019In: Water Research, ISSN 0043-1354, E-ISSN 1879-2448, Vol. 148, p. 515-525Article in journal (Refereed)
    Abstract [en]

    Sediment capping with activated carbon (AC) is an effective technique used in remediation of contaminated sediments, but the ecological effects on benthic microbial activity and meiofauna communities have been largely neglected. This study presents results from a 4-week experiment investigating the influence of two powdered AC materials (bituminous coal-based and coconut shell-derived) and one control material (clay) on biogeochemical processes and meiofauna in contaminated sediments. Capping with AC induced a 62‒63% decrease in denitrification and a 66‒87 % decrease in dissimilatory nitrate reduction to ammonium (DNRA). Sediment porewater pH increased from 7.1 to 9.0 and 9.7 after addition of bituminous AC and biomass-derived AC, respectively. High pH (>8) persisted for at least two weeks in the bituminous AC and for at least 24 days in the coconut based AC, while capping with clay had no effect on pH. We observed a strong impact (nitrate fluxes being halved in presence of AC) on nitrification activity as nitrifiers are sensitive to high pH. This partly explains the significant decrease in nitrate reduction rates since denitrification was almost entirely coupled to nitrification. Total benthic metabolism estimated by sediment oxygen uptake was reduced by 30 and 43 % in presence of bituminous coal-based AC and coconut shell-derived AC, respectively. Meiofauna abundances decreased by 60‒62 % in the AC treatments. Taken together, these observations suggest that AC amendments deplete natural organic carbon, intended as food, to heterotrophic benthic communities. Phosphate efflux was 91 % lower in presence of bituminous AC compared to untreated sediment probably due to its content of aluminum (Al) oxides, which have high affinity for phosphate. This study demonstrates that capping with powdered AC produces significant effects on benthic biogeochemical fluxes, microbial processes and meiofauna abundances, which are likely due to an increase in porewater pH and to the sequestration of natural, sedimentary organic matter by AC particles.

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  • 3.
    Borefur, Christoffer
    et al.
    Jönköping University, School of Engineering, JTH, Civil Engineering and Lighting Science.
    Berggren, Emma
    Jönköping University, School of Engineering, JTH, Civil Engineering and Lighting Science.
    Klimatanpassa marksanering: Förbättringsförslag för ökad tillämpning av biologiska marksaneringsmetoder2020Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Purpose: In Sweden, there are area that are polluted and in need of remediation. However, soil remediation processes have a negative secondary impact on the climate. There are various soil remediation methods to apply, of which dig and dump are the most frequently used. The method involves although high emissions of carbon dioxide. By increased use of alternative soil remediation methods, such as biological soil remediation methods, can lead to reduced impact on the climate. When choosing a remediation method, sustainability is increasingly integrated, but most decisions are still based on other factors. Psychological, social and institutional barriers are considered to have counteracted the assumption of a sustainable behaviour. Therefore, further research on stakeholder attitudes may promote the implementation of such behaviour. The aim of the work is to present suggestions for improvement on how the climate impact can be reduced in soil remediation projects.

    Method: The study was performed as a qualitative survey. Empirical data was obtained in verbal form through the methods literature review, document analysis and interview. From an available group, six respondents were selected who represent significant stakeholders in soil remediation projects. Stakeholders were private and public clients, contractors, consultants and regulators. Analysed documents were reports from the Swedish Environmental Protection Agency that is about the post-treatment of contaminated areas in Sweden.

    Findings: The study indicates that biological soil remediation methods have a lower impact on the climate than dig and dump. Furthermore, it appeared that the main factors in choosing a soil remediation method was type of contamination, time for remediation and when contamination is detected in projects. According to this background, biological methods are less applied than dig and dump. However, the study presents suggestions for improvements of how biological alternatives can be encouraged, for instance are more reference objects needed where biological soil remediation methods have been applied.

    Implications: One conclusion from the study is that existing regulations should be changed to make landfill more difficult and to facilitate re-use of polluted masses, and the fees for landfill should be increased. In addition, more reference objects need to be generated in Sweden that validate that biological soil remediation methods achieve acceptable levels of pollution. Furthermore, stakeholders in soil remediation projects should cooperate more, even across national borders, and together venture to try biological soil remediation methods.

    Limitations: The result is only valid for biological soil remediation methods and dig and dump for organic pollutants in soil. The study includes few respondents from av geographic limited available group, which means that the result cannot be generalized with certainty. Therefore, the study should be regarded as exploratory and the results thereafter.

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  • 4.
    Das, Sarbashis
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Cell and Molecular Biology, Chemical Biology.
    Pettersson, B M Fredrik
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Cell and Molecular Biology, Chemical Biology.
    Behra, Phani Rama Krishna
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Cell and Molecular Biology, Chemical Biology.
    Ramesh, Malavika
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Cell and Molecular Biology, Chemical Biology.
    Dasgupta, Santanu
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Cell and Molecular Biology, Microbiology.
    Bhattacharya, Alok
    Kirsebom, Leif A
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Cell and Molecular Biology, Chemical Biology.
    Characterization of three Mycobacterium spp. with potential use in bioremediation by genome sequencing and comparative genomics2015In: Genome Biology and Evolution, E-ISSN 1759-6653, Vol. 7, no 7, p. 1871-1886Article in journal (Refereed)
    Abstract [en]

    We provide the genome sequences of the type strains of the polychlorophenol-degrading Mycobacterium chlorophenolicum (DSM43826), the degrader of chlorinated aliphatics Mycobacterium chubuense (DSM44219) and Mycobacterium obuense (DSM44075) that has been tested for use in cancer immunotherapy. The genome sizes of M. chlorophenolicum, M. chubuense and M. obuense are 6.93, 5.95 and 5.58 Mbps with GC-contents of 68.4, 69.2 and 67.9%, respectively. Comparative genomic analysis revealed that 3254 genes are common and we predicted approximately 250 genes acquired through horizontal gene transfer from different sources including proteobacteria. The data also showed that the biodegrading Mycobacterium spp. NBB4, also referred to as M. chubuense NBB4, is distantly related to the M. chubuense type strain and should be considered as a separate species, we suggest it to be named M. ethylenense NBB4. Among different categories we identified genes with potential roles in: biodegradation of aromatic compounds, and copper homeostasis. These are the first non-pathogenic Mycobacterium spp. found harboring genes involved in copper homeostasis. These findings would therefore provide insight into the role of this group of Mycobacterium spp. in bioremediation as well as the evolution of copper homeostasis within the Mycobacterium genus.

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  • 5.
    Delestig, Sara
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Industrial Biotechnology.
    Optimisation of Volatile Fatty Acid Production via Anaerobic Fermentation of Primary Sludge for Sustainable Wastewater Treatment Processes2024Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Biological nutrient removal processes in wastewater treatment plants (WWTPs) rely on the availability of easily degradable carbon compounds, such as volatile fatty acids (VFAs). This study explored the feasibility of VFA production through biological anaerobic fermentation of primary sludge (PS) sourced from Fillan WWTP in Sundsvall, Sweden. The impact of temperature and hydraulic retention time (HRT) was investigated. 

    Results revealed higher VFA concentrations at 37 °C compared to 20 °C and 55 °C, indicating temperature's impact on VFA production. Additionally, optimal temperature and HRT combinations were explored, with 37 °C and a four-day HRT showing the highest VFA yields. The potential for nutrient removal at Fillan WWTP using the VFAs produced as a carbon source was assessed through theoretical calculations and experimental validation. The findings revealed that using an internally produced carbon source derived from PS could be an alternative to commercial (external) carbon sources in the wastewater treatment processes as a sustainable and economically advantageous strategy. 

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  • 6.
    Eivazihollagh, Alireza
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Svanedal, Ida
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Edlund, Håkan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Norgren, Magnus
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    On chelating surfactants: Molecular perspectives and application prospects2019In: Journal of Molecular Liquids, ISSN 0167-7322, E-ISSN 1873-3166, Vol. 278, p. 688-705Article in journal (Refereed)
    Abstract [en]

    Chelating agents, molecules that very strongly coordinates certain metal ions, are used industrially as well as in consumer products to minimize disturbances and increase performance of reactions and applications. The widely used sequestering agents, nitrilotriacetic acid (NTA), ethylenediaminetetraacetic acid (EDTA) and diethylenetriaminepentaacetic acid (DTPA) belong to this branch of readily water-soluble compounds. When these chemical structures also have hydrophobic parts, they are prone to adsorb at air-water interfaces and to self-assemble. Such bifunctional molecules can be called chelating surfactants and will have more extended utilization prospects than common chelating agents or ordinary ionic surfactants. The present review attempts to highlight the fundamental behavior of chelating surfactants in solution and at interfaces, and their very specific interactions with metal ions. Methods to recover chelating surfactants from metal chelates are also described. Moreover, utilization of chelating surfactants in applications for metal removal in environmental engineering and mineral processing, as well as for metal control in the fields of biology, chemistry and physics, is exemplified and discussed.

  • 7.
    Enstedt, Henric
    Linköping University, Department of Physics, Chemistry and Biology, Chemistry. Linköping University, The Institute of Technology.
    Using a biotrickling filter for degradation of cypermethrin, an insecticide frequently used in Tahuapalca, Bolivia2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The feasibility of using bench-scale biotrickling filter reactors inoculated with the fungus UBAF004, isolated from soil in Tahuapalca, for treatment of water contaminated with cypermethrin was investigated. Wood chips, gravel and ceramics were tested as packing materials for the reactors in batch experiments in small glass flasks. Wood proved to be the material on which the fungus grew best and was thus chosen as the packing material for the reactors. It was determined that UBAF004 had quite low competitive strength compared to other microorganisms when growing on wood and gravel but not necessarily on ceramics. UBAF004 grew slowly in the reactors leading to poor degradation performance. The results obtained indicate that it will be challenging to use UBAF004 for treatment of water contaminated with cypermethrin in Tahuapalca. The single largest issue is to find a way to establish a stable population of the fungus in the reactor and to protect it from being out competed by other microorganisms.

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    Using a biotrickling filter for degradation of cypermethrin, an insecticide frequently used in Tahuapalca, Bolivia
  • 8.
    Figueroa, Daniela
    et al.
    Umeå University;Umeå Marine Sciences Centre.
    Rowe, O. F.
    Umeå University;University of Helsinki, Finland.
    Paczkowska, Joanna
    Umeå University.
    Legrand, Catherine
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Andersson, Agneta
    Umeå University ; Umeå Marine Sciences Centre.
    Allochthonous Carbon-a Major Driver of Bacterioplankton Production in the Subarctic Northern Baltic Sea2016In: Microbial Ecology, ISSN 0095-3628, E-ISSN 1432-184X, Vol. 71, no 4, p. 789-801Article in journal (Refereed)
    Abstract [en]

    Heterotrophic bacteria are, in many aquatic systems, reliant on autochthonous organic carbon as their energy source. One exception is low-productive humic lakes, where allochthonous dissolved organic matter (ADOM) is the major driver. We hypothesized that bacterial production (BP) is similarly regulated in subarctic estuaries that receive large amounts of riverine material. BP and potential explanatory factors were measured during May-August 2011 in the subarctic Råne Estuary, northern Sweden. The highest BP was observed in spring, concomitant with the spring river-flush and the lowest rates occurred during summer when primary production (PP) peaked. PLS correlations showed that ∼60 % of the BP variation was explained by different ADOM components, measured as humic substances, dissolved organic carbon (DOC) and coloured dissolved organic matter (CDOM). On average, BP was threefold higher than PP. The bioavailability of allochthonous dissolved organic carbon (ADOC) exhibited large spatial and temporal variation; however, the average value was low, ∼2 %. Bioassay analysis showed that BP in the near-shore area was potentially carbon limited early in the season, while BP at seaward stations was more commonly limited by nitrogen-phosphorus. Nevertheless, the bioassay indicated that ADOC could contribute significantly to the in situ BP, ∼60 %. We conclude that ADOM is a regulator of BP in the studied estuary. Thus, projected climate-induced increases in river discharge suggest that BP will increase in subarctic coastal areas during the coming century.

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  • 9.
    Laohaprapanon, Sawanya
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Marques, Marcia
    Rio de Janeiro State University, Brazil.
    Hogland, William
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Anaerobic baffled reactor coupled with chemical precipitation for treatment and toxicity reduction of industrial wastewater2014In: Environmental technology, ISSN 0959-3330, E-ISSN 1479-487X, Vol. 35, no 2, p. 154-162Article in journal (Refereed)
    Abstract [en]

    This study describes the reduction of soluble chemical oxygen demand (CODs) and the removal of dissolved organic carbon (DOC), formaldehyde (FA) and nitrogen from highly polluted wastewater generated during cleaning procedures in wood floor manufacturing using a laboratory-scale biological anaerobic baffled reactor followed by chemical precipitation using MgCl2·6H2O+Na2HPO4. By increasing the hydraulic retention time from 2.5 to 3.7 and 5 days, the reduction rates of FA, DOC and CODs of nearly 100%, 90% and 83%, respectively, were achieved. When the Mg:N:P molar ratio in the chemical treatment was changed from 1:1:1 to 1.3:1:1.3 at pH 8, the NH4+ removal rate increased from 80% to 98%. Biologically and chemically treated wastewater had no toxic effects on Vibrio fischeri and Artemia salina whereas chemically treated wastewater inhibited germination of Lactuca sativa owing to a high salt content. Regardless of the high conductivity of the treated wastewater, combined biological and chemical treatment was found to be effective for the removal of the organic load and nitrogen, and to be simple to operate and to maintain. A combined process such as that investigated could be useful for on-site treatment of low volumes of highly polluted wastewater generated by the wood floor and wood furniture industries, for which there is no suitable on-site treatment option available today.

  • 10.
    Lumsén, Louise
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Malmer, Elsa
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Ljungberg, Alice
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Rosendahl, Sara
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Rosendal, Linnea
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Westander, Lisa
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Metallhalter i fibersediment: Utvärdering av industriers utsläpp längs Norrlandskusten2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    I det här projektet har halten tungmetaller, miljöfarliga metaller och andra metallföroreningar undersökts i fiberhaltiga bottensediment längs Norrlandskusten i syfte att bredda förståelsen för saneringsbehovet. Industrier har använt olika processer i sin verksamhet som släppt ut fiberrikt avfall i vilka en mängd föroreningar och däribland miljöfarliga metaller har lagrats. Metallerna ansamlas i sedimenten och bör påvisas vid provtagning, men så är enligt denna studie inte alltid fallet. Många faktorer spelar in i om tungmetallerna lagrats och finns kvar i sedimenten eller inte. Två av dessa faktorer skulle kunna vara halten organiskt kol i sedimenten samt svavelhalten, alternativt de båda i relation till varandra. För att ta reda på vad som finns i sedimenten har data från Sveriges Geologiska Undersökning (SGU) använts. Samma data ligger till grund för den stora studie och riskklassning som genomfördes av SGU, Havs- och vattenmyndigheten och fem länsstyrelser i Norrland, projektet FIN15.

    I projektet har data från fem undersökta områden analyserats. Områdena är Norrsundet, Ljusnefjärden, Iggesund, Marmen och Yttre fjärden. Datan har analyserats med avseende på vilken industri som funnits i vilket område, i vilka sediment vilka metaller finns samt om det går att påvisa någon koppling mellan vilken industri som använts på platsen. I syfte att avgöra om metallkoncentrationerna i sedimentenär betydligt högre än de naturliga bakgrundsnivåerna har jämförvärden från Bottniska viken använts som referensvärden för "neutral metallkoncentration" i sedimenten.

    Resultatet visar att det i många fall kan dras kopplingar mellan typ av industri och metallhalt, men att det finns många faktorer som är avgörande för huruvida metallerna finns kvar i sedimenten eller inte. Svavlet och det totala organiska kolets (TOC) påverkan på metallernas koncentration visade sig vara mer komplex än vad som framställdes enligt teorin. Vid vissa områden ökade metallkoncentrationerna med ökad kolhalt, i andra minskade den. Det går i denna undersökning heller inte att påvisa ett starkt samband mellan svavelhalten och halten förorening.

    Metoden som använts går att utveckla och fler faktorer bör beaktas för att få en bättre helhetsbild. De fem analyserade områdena har alla varierande geologi och har haft en kombination av flera olika industrier. Det går inte att med säkerhet fastställa att en viss metall kommer från en viss industrityp, men det går att se samband mellan förhöjda halter metaller och industriområden med gemensamma industrityper i allmänhet.

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  • 11.
    Mitter, Eduardo Kovalski
    et al.
    Sao Paulo State University, Brazil.
    Santos, Graziely Cristina
    Almeida, Erica Janaína Rodrigues
    Sao Paulo State University, Brazil.
    Morão, Luana Galvão
    Sao Paulo State University, Brazil.
    Rodrigues, Heide Dayane Prates
    Sao Paulo State University, Brazil.
    Corso, Carlos Renato
    Sao Paulo State University, Brazil.
    Analysis of Acid Alizarin Violet N Dye Removal Using Sugarcane Bagasse as Adsorbent2012In: Water, Air and Soil Pollution, ISSN 0049-6979, E-ISSN 1573-2932, Vol. 223, no 2, p. 765-770Article in journal (Refereed)
    Abstract [en]

    With the development of the textile industry, there has been a demand for dye removal from contaminated effluents. In recent years, attention has been directed toward various natural solid materials that are capable of removing pollutants from contaminated water at low cost. One such material is sugarcane bagasse. The aim of the present study was to evaluate adsorption of the dye Acid Violet Alizarin N with different concentrations of sugarcane bagasse and granulometry in agitated systems at different pH. The most promising data (achieved with pH 2.5) was analyzed with both Freundlich and Langmuir isotherms equations. The model that better fits dye adsorption interaction into sugarcane bagasse is Freundlich equation, and thus the multilayer model. Moreover, a smaller bagasse granulometry led to greater dye adsorption. The best treatment was achieved with a granulometry value lower than 0.21 mm at pH 2.50, in which the total removal was estimated at a concentration of 16.25 mg mL−1. Hence, sugarcane bagasse proves to be very attractive for dye removal from textile effluents.

  • 12.
    Mohanty, Amar K.
    et al.
    Bioproducts Discovery and Development Centre, Department of Plant Agriculture, University of Guelph, Guelph, Ontario, Canada; School of Engineering, University of Guelph, Guelph, Ontario, Canada.
    Vivekanandhan, Singaravelu
    Sustainable Materials and Nanotechnology Lab (SMNL), Department of Physics, V.H.N.S.N. College (Autonomous), Virudhunagar, Tamil Nadu, India.
    Das, Oisik
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Fire Engineering.
    Romero Millán, Lina M.
    Universidad Nacional de Colombia – Sede Bogotá, Facultad de Ingeniería, Ciudad Universitaria, Bogotá, Colombia.
    Klinghoffer, Naomi B.
    Department of Chemical and Biochemical Engineering, The University of Western Ontario, London, Ontario, Canada; Institute for Chemicals and Fuels from Alternative Resources (ICFAR), The University of Western Ontario, London, Ontario, Canada.
    Nzihou, Ange
    IMT Mines Albi, RAPSODEE CNRS UMR 5302, Université de Toulouse, Campus Jarlard, Toulouse, France; Andlinger Center for Energy and the Environment, Princeton University, Princeton, NJ, USA.
    Misra, Manjusri
    Bioproducts Discovery and Development Centre, Department of Plant Agriculture, University of Guelph, Guelph, Ontario, Canada; School of Engineering, University of Guelph, Guelph, Ontario, Canada.
    Biocarbon materials2024In: Nature Reviews Methods Primers, E-ISSN 2662-8449, Vol. 4, no 1, article id 19Article in journal (Refereed)
  • 13.
    Ni, Gaofeng
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    When bioelectrochemical systems meet extremophiles, possibilities and challenges2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Extremophiles are microorganisms live and thrive in extreme environments that are harsh and hostile to most forms of life on earth (e.g. low pH, low temperature, high pH and high salinity). They have developed strategies to obtain nutrients and conserve energy to sustain life under these adverse conditions. Such metabolic capabilities are valuable to be exploit for industrial applications such as the remediation of environmental pollutions, which typically bring about extreme physicochemical conditions. The advancing technology bioelectrochemical systems can utilize the microbial metabolism to oxidize a substrate while simultaneously recover electrical energy or produce a useful product in an electrochemical set-up. It enables the remediation of pollutions, and its integration with extremophiles has opened up a wide range of possibilities to tackle various industrial waste streams with extreme conditions in an environmentally friendly manner. Inorganic sulfur compounds such as tetrathionate, thiocyanate and sulfide that originate from mining, metal refinery and petroleum industries are toxic and hazardous to the recipient water body and human health if discharged untreated. The remediation of these three compounds with bioelectrochemical systems that incorporates extremophiles was investigated in three separate studies of this thesis. 16S rRNA gene amplicon sequencing, metagenomics and metatranscriptomics are utilized to profile the microbial communities, and to understand their metabolic potential and states.

     

    Tetrathionate degradation with acidophilic microorganisms in microbial fuel cells at pH 2 was demonstrated in the first study of this thesis. Electricity was produced from the oxidation of tetrathionate, facilitated by the anodic microbiome. 16S rRNA gene amplicon sequencing showed that this community was dominated by members of the genera Thermoplasma, Ferroplasma, Leptospirillum, Sulfobacillus and Acidithiobacillus. Metagenomic analysis reconstructed genomes that were most similar to the genera Ferroplasma, Acidithiobacillus, Sulfobacillus and Cuniculiplasma. Together with metatranscriptomic analysis, it was indicated that this microbial community was metabolizing tetrathionate and other intermediate sulfur compounds via multiple pathways, the electrons released from oxidation were suggested to be transferred to the electrode via soluble electron shuttles. In addition, the Ferroplasma-like population in this study was suggested to be active in metabolising inorganic sulfur compounds and synthesizing soluble electron shuttles. Since characterized Ferroplasma species do not utilize inorganic sulfur compounds, the anodic compartment might have selected a novel Ferroplasma population.

     

    Next, thiocyanate degradation with psychrophilic microorganisms in microbial fuel cells at 8 °C was demonstrated for the first time. Electricity generation alongside with thiocyanate degradation facilitated by the anodic microbiome was observed. 16S rRNA gene amplicon sequencing and metatranscriptomics suggested that Thiobacillus was the predominant and most active population. mRNA analysis revealed that thiocyanate was metabolized primarily via the ‘cyanate’ degradation pathway; the resultant sulfide was oxidized; ammonium was assimilated; carbon dioxide was fixed as carbon source. It was also suggested by mRNA analysis that the consortium used multiple mechanisms to acclimate low temperature such as the synthesis of cold shock proteins, cold inducible proteins and molecular chaperones.

     

    Finally, sulfide removal with haloalkaliphilic microorganisms in microbial electrolysis cells operated at pH 8.8 to 9.5 and with 1.0 M sodium ion was investigated. The anodic microbiome was hypothesized to facilitate current generation by the oxidation of sulfide and of intermediate sulfur compounds to sulfate, which was supported by chemical analysis and microbial profiling. Dominant populations from the anode had 16S rRNA gene sequences that aligned within the genera Thioalkalivibrio, Thioalkalimicrobium, and Desulfurivibrio, which are known for sulfide oxidation. Intriguingly, Desulfurivibrio dominated the electrode-attached community, possibly enriched by the electrode as a selecting pressure. This finding suggested a novel role of this organism to carry out sulfide oxidation coupled to electron transfer to the electrode.

     

    These three studies demonstrated the possibilities of utilizing extremophilic bioelectrochemical systems to remediate various inorganic sulfur pollution streams. The advancing molecular microbiological tools facilitated the investigation towards the composition and metabolic state of the microbial community. Challenges remain in a more thorough understanding regarding the metabolism of extremophiles (e.g. sulfur metabolism and extracellular electron transfer) and better energy recovery in bioelectrochemical systems.

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  • 14.
    Olofsson, Martin
    et al.
    Linnéuniversitetet, Institutionen för biologi och miljö (BOM).
    Lindehoff, Elin
    Linnéuniversitetet, Institutionen för biologi och miljö (BOM).
    Frick, Brage
    Linnéuniversitetet, Institutionen för biologi och miljö (BOM).
    Svensson, Fredrik
    Linnéuniversitetet, Institutionen för biologi och miljö (BOM).
    Legrand, Catherine
    Linnéuniversitetet, Institutionen för biologi och miljö (BOM).
    Baltic Sea microalgae transform cement flue gas into valuable biomass2015In: Algal Research, ISSN 2211-9264, Vol. 11, p. 227-233Article in journal (Refereed)
    Abstract [en]

    We show high feasibility of using cement industrial flue gas as CO2 source for microalgal cultivation. The toxicity of cement flue gas (12-15% CO2) on algal biomass production and composition (lipids, proteins, carbohydrates) was tested using monocultures (Tetraselmis sp., green algae, Skeletonema marinoi, diatom) and natural brackish communities. The performance of a natural microalgal community dominated by spring diatoms was compared to a highly productive diatom monoculture S. marinoi fed with flue gas or air-CO2 mixture. Flue gas was not toxic to any of the microalgae tested. Instead we show high quality of microalgal biomass (lipids 20-30% DW, proteins 20-28% DW, carbohydrates 15-30% DW) and high production when cultivated with flue gas addition compared to CO2-air. Brackish Baltic Sea microalgal communities performed equally or better in terms of biomass quality and production than documented monocultures of diatom and green algae, often used in algal research and development. Hence, we conclude that microalgae should be included in biological solutions to transform waste into renewable resources in coastal waters. (C) 2015 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

  • 15.
    Olofsson, Martin
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Lindehoff, Elin
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Frick, Brage
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Svensson, Fredrik
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Legrand, Catherine
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Baltic Sea microalgae transform cement flue gas into valuable biomass2015In: Algal Research, ISSN 2211-9264, Vol. 11, p. 227-233Article in journal (Refereed)
    Abstract [en]

    We show high feasibility of using cement industrial flue gas as CO2 source for microalgal cultivation. The toxicity of cement flue gas (12-15% CO2) on algal biomass production and composition (lipids, proteins, carbohydrates) was tested using monocultures (Tetraselmis sp., green algae, Skeletonema marinoi, diatom) and natural brackish communities. The performance of a natural microalgal community dominated by spring diatoms was compared to a highly productive diatom monoculture S. marinoi fed with flue gas or air-CO2 mixture. Flue gas was not toxic to any of the microalgae tested. Instead we show high quality of microalgal biomass (lipids 20-30% DW, proteins 20-28% DW, carbohydrates 15-30% DW) and high production when cultivated with flue gas addition compared to CO2-air. Brackish Baltic Sea microalgal communities performed equally or better in terms of biomass quality and production than documented monocultures of diatom and green algae, often used in algal research and development. Hence, we conclude that microalgae should be included in biological solutions to transform waste into renewable resources in coastal waters. (C) 2015 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

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  • 16.
    Sandhi, Arifin
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Gao, Ling
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science. Beihua University, China.
    Rosenlund, Joacim
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Landberg, Tommy
    Stockholm University, Sweden.
    Growing Salix spp. on heavy metal contaminated sediment (Oskarshamn, Sweden) as a joint phytoremediation and circular economy approach2023In: Environmental Advances, E-ISSN 2666-7657, Vol. 14, article id 100438Article in journal (Refereed)
    Abstract [en]

    The sediments of rivers or harbours have always been considered sinks for numerous heavy metals, pesticides, chemicals and contaminants of anthropogenic origin. The eco-friendly management of contaminated sediment have received attention due to their large-scale presence in harbour areas. Application of bioenergy crop species, such as Salix spp., have shown a strong potential for reducing heavy metals from the contaminated sediment. The aim of this study was to investigate the application of Salix spp. on contaminated dredged sediment and heavy metal accumulation and translocation patterns in different parts of plants. Two Salix cultivars (Wilhelm and Ester; commercially available in Sweden) were cultivated in contaminated sediment for 5 weeks in a field setting. Heavy metals (Cd, Cu, Pb, Ni and Zn) content in different plant parts (root, cutting, shoot and leaves) were analysed by using atomic absorption spectrophotometer (AAS). The result indicated that the root biomass production was negatively affected for both cultivars due to the contaminated sediment medium, even though no morphological symptoms were present. Both Cd and Cu net accumulation were found to be significantly higher in Ester cultivars. The low translocation of heavy metals in Salix spp. hints that accumulated heavy metals are stored in the root parts. Low translocation of heavy metals from contaminated sediments gives a strong potential for using a growth medium to utilize phosphorus (P) in the sediment from a circular economy and bioeconomy perspective.

  • 17.
    Sandhi, Arifin
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science. Stockholm university, Sweden.
    Greger, Maria
    Stockholm university, Sweden.
    Moss based constructed wetland system: is it possible to use aquatic moss (warnstorfia fluitans) for removal of as in an eco-friendly approach?2018In: Book of Abstracts: Linnaeus Eco-Tech 2018 / [ed] Yahya Jani, Jelena Lundström, Viveka Svensson, William Hogland, Kalmar, Växjö: Linnaeus university , 2018, p. 17-Conference paper (Refereed)
    Abstract [en]

    The heavy metal and metalloid contaminated groundwater is considered as one of the major global environmental disasters that need sustainable solutions. One sustainable environment-friendly solution is using plant-based remediation, or phytoremediation. For contaminated water aquatic plant based phytofiltration could be applied. A Swedish aquatic moss species (Warnstorfia fluitans) have been discovered to accumulate high levels of As (arsenic) from the water. In a number of areas in Sweden, the As content in the groundwater is high due to mining activities and geochemical conditions. Our hypothesis was that since this moss species could accumulate As from contaminated water it would be possible to apply in constructed wetland system for removal of As from water. The aim of this study was to investigate the removal of As from the outlet water by using W. fluitans in constructed mesocosm type wetland systems with various water flow speeds under greenhouse conditions. Besides these, As content in the vegetables (lettuce, Latuca sativa) grown in this outlet water was also analysed. The total As concentration was analysed with hydride generated atomic absorption spectrophotometry (HG-AAS). Results showed that W. fluitans could reduce the As concentration in the water with 36 and 56% from initial As concentration at high (5 mL/min) and low (1.5 mL/min) water flow rate, respectively. The As concentration in the vegetables was also lower when low flow outlet has been applied as irrigation water. In conclusion, the result fits our hypothesis that aquatic moss could be used in the constructed wetland system to reduce As content in irrigation water and by that also in the irrigated vegetables.

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    LNU Eco-Tech Abstract
  • 18.
    Sandhi, Arifin
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering. Department of Ecology, Environment and Plant Sciences, Stockholm University, SE 10691 Stockholm, Sweden.
    Landberg, Tommy
    Department of Ecology, Environment & Plant Sciences, Stockholm University, SE-10691 Stockholm, Sweden.
    Greger, Maria
    Department of Ecology, Environment & Plant Sciences, Stockholm University, SE-10691 Stockholm, Sweden.
    Phytofiltration of arsenic by aquatic moss (Warnstorfia fluitans)2017In: Environmental Pollution, ISSN 0269-7491, E-ISSN 1873-6424Article in journal (Refereed)
    Abstract [en]

    This work investigates whether aquatic moss (Warnstorfia fluitans) originating from an arsenic (As)-contaminated wetland close to a mine tailings impoundment may be used for phytofiltration of As. The aim was to elucidate the capacity of W. fluitans to remove As from arsenite and arsenate contaminated water, how nutrients affect the As uptake and the proportion of As adsorption and absorption by the moss plant, which consists of dead and living parts.

    Arsenic removal from 0, 1, or 10% Hoagland nutrient solution containing 0–100 μM arsenate was followed over 192 h, and the total As in aquatic moss after treatment was analysed. The uptake and speciation of As in moss cultivated in water containing 10 μM arsenate or arsenite were examined as As uptake in living (absorption + adsorption) and dead (adsorption) plant parts.

    Results indicated that W. fluitans removed up to 82% of As from the water within one hour when 1 μM arsenate was added in the absence of nutrients. The removal time increased with greater nutrient and As concentrations. Up to 100 μM As had no toxic effect on the plant biomass. Both arsenite and arsenate were removed from the solution to similar extents and, independent of the As species added, more arsenate than arsenite was found in the plant. Of the As taken up, over 90% was firmly bound to the tissue, a possible mechanism for resisting high As concentrations. Arsenic was both absorbed and adsorbed by the moss, and twice as much As was found in living parts as in dead moss tissue. This study revealed that W. fluitans has potential to serve as a phytofilter for removing As from As-contaminated water without displaying any toxic effects of the metalloid.

  • 19.
    Santos, Graziely Cristina
    et al.
    Univ Estadual Paulista, Brazil.
    Corso, Carlos Renato
    Univ Estadual Paulista, Brazil.
    Comparative Analysis of Azo Dye Biodegradation by Aspergillus oryzae and Phanerochaete chrysosporium2014In: Water, Air and Soil Pollution, ISSN 0049-6979, E-ISSN 1573-2932, Vol. 225, no 7, article id 2026Article in journal (Refereed)
    Abstract [en]

    The textile industry often releases effluents into the environment without proper treatment or complete dye removal. Azo dyes, which are characterized by azo groups (―N═N―), are frequently used in the textile industry. Among the different wastewater treatment methods available, biological treatment has been extensively studied. The aim of the present study was to compare the biodegradation of the azo dye Direct Blue 71 by the fungi Phanerochaete chrysosporium and Aspergillus oryzae in paramorphogenic form using a 100 μg/ml dye solution. Biodegradation tests were performed within 240 h. The absorbance values obtained with UV-VIS spectrophotometry were used to determine the absorbance ratio and the percentage of dye discoloration following the biodegradation test. FTIR analysis allowed the identification of molecular compounds in the solution before and after biodegradation. Both A. oryzae and P. chrysosporium demonstrated considerable potential regarding the biodegradation of dyes in wastewater. These results may contribute toward improving effluent treatment systems in the textile industry.

  • 20.
    Sar, Taner
    et al.
    University of Borås, Faculty of Textiles, Engineering and Business.
    Chen, Yang
    Bai, Yu
    Liu, Benjamin
    Agarwal, Pooja
    Stark, Benjamin C.
    Akbas, Meltem Yesilcimen
    Combining co-culturing of Paenibacillus strains and Vitreoscilla hemoglobin expression as a strategy to improve biodesulfurization2021In: Letters in Applied Microbiology, ISSN 0266-8254, E-ISSN 1472-765X, Vol. 72, no 4, p. 484-494Article in journal (Refereed)
    Abstract [en]

    Enhancement of the desulfurization activities of Paenibacillus strains 32O-W and 32O-Y were investigated using dibenzothiophene (DBT) and DBT sulfone (DBTS) as sources of sulphur in growth experiments. Strains 32O-W, 32O-Y and their co-culture (32O-W plus 32O-Y), and Vitreoscilla hemoglobin (VHb) expressing recombinant strain 32O-Yvgb and its co-culture with strain 32O-W were grown at varying concentrations (0.1–2 mmol l-1) of DBT or DBTS for 96 h, and desulfurization measured by production of 2-hydroxybiphenyl (2-HBP) and disappearance of DBT or DBTS. Of the four cultures grown with DBT as sulphur source, the best growth occurred for the 32O-Yvgb plus 32OW co-culture at 0.1 and 0.5 mmol l-1 DBT. Although the presence of vgb provided no consistent advantage regarding growth on DBTS, strain 32O-W, as predicted by previous work, was shown to contain a partial 4S desulfurization pathway allowing it to metabolize this 4S pathway intermediate.

  • 21.
    Sitara, Angeliki
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Molecular Biomimetics. Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Heterologous expression of IsPETase and IsMHETase in Synechocystis sp. PCC 6803 for efficient PET degradation2022Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
    Abstract [en]

    Plastic waste is an emerging problem of the 20th century. Polyethylene terephthalate (PET), a synthetic polyester, is used industrially in bottle packaging and textiles, due to its durability and resistance to damage. Vast accumulation of PET over the last decades has resulted in increase of microplastics and nanoplastics in the oceans, which affect marine but also human life. Plastic bioremediation is expected to offer a carbon-neutral alternative to that problem.The identification of novel PET-degrading enzymes, such as PETase and MHETase from Idionella sakaiensis 201-F6, is a promising alternative for biological treatment of PET waste.

    In this study, several strains harbouring a chimera of MHETase: DuraPETase or DuraPETase(engineered version of PETase) were created in Synechocystis sp. PCC 6803, that will provide insight into plastic degradation by cyanobacteria. Synechocystis managed to express DuraPETase under Ptrc and PpsbA2 promoter in a self-replicative vector and in the genome. Purification of DuraPETase from Synechocystis yielded 1mg/ml of protein, which showed enzymatic activity towards a synthetic analogue, p-NPA, but also commercial PET film, as demonstrated by the detection of terephthalic acid (the degradation product) through high performance liquid chromatography after 14 days.

    These results indicate the potential of using cyanobacteria for industrial applications, coupling carbon assimilation from the environment through photosynthesis with plastic bioremediation. Further research is needed to optimize the system so that it is applicable in industrial applications.

  • 22.
    Vargas, Javier Edo.
    et al.
    Universidad De Los Andes, Bogotá, Colombia.
    Dussán, Jenny
    Universidad De Los Andes, Bogotá, Colombia.
    Adsorption of Toxic Metals and Control of Mosquito-borne Disease by Lysinibacillus sphaericus: Dual Benefits for Health and Environment2016In: Biomedical and environmental sciences, ISSN 0895-3988, E-ISSN 2214-0190, Vol. 29, no 3, p. 187-196Article in journal (Refereed)
  • 23.
    Vargas, Javier Edo
    et al.
    Universidad De Los Andes, Bogotá, Colombia.
    Dussán, Jenny
    Universidad De Los Andes, Bogotá, Colombia.
    Encapsulation and immobilization of the S-layer protein of Lysinibacillus sphaericus in an alginate matrix for chromium adsorption2017In: International Biodeterioration & Biodegradation, ISSN 0964-8305, E-ISSN 1879-0208, Vol. 116, p. 141-146Article in journal (Refereed)
1 - 23 of 23
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