Ahmed M. Sadeq, Zainab Z. Ismail

Iraqi Journal of Chemical and Petroleum Engineering • 2024

This study aimed to comprehensively characterize and identify microalgae inhabiting the biocathode compartment of a photosynthetic microbial desalination cell (PMDC). Also, modeling of microalgae growth in the biocathode was considered as well as the interrelation between the growth of microalgae and dissolved oxygen (DO) generation within the biocathode. The general performance of the PMDC was evaluated based on; (1) organic content removal from the real domestic wastewater fed to the anode compartment, (2) salinity removal from actual seawater in the desalination compartment, and (3) power generation in the PMDC. The results unveiled the presence of two distinct microalgae species, specifically Coelastrella sp. and Mariniradius saccharolyticus, which were thoroughly characterized using 16S rRNA and ITS gene sequencing within the cathodic chamber of the PMDC. Following sequence editing and trimming, the resulting sequences were meticulously submitted to the NCBI GenBank and juxtaposed with other sequences utilizing the GenBank online BLAST software. Importantly, the obtained data demonstrated a good correlation with coefficients of determination (R²) reaching 0.83, as per the employed kinetic models. Complete removal of up to 99.11% of organic content from the real domestic wastewater was obtained in the PMDC system with maximum efficiency of desalination elimination of 80.95% associated with a maximum power output of 420 mW/m3 in the system.

M Samartha, R K S Pippal, V K Sethi

IOP Conference Series: Earth and Environmental Science • 2022

Abstract In present scenario when there is great hike in energy demand which results in increased prices of petroleum products and the big matter of concern is that the resources are diminishing so rapidly, these diminishing fuels should be replaced by biofuels. Other sources of biofuels are limited and difficult to cultivate therefore microalgae has comes out as an important source of renewable biofuel. Microalgae grow in the presence of sunlight and CO2, and those rich in lipids are excellent source of biofuels (biodiesel) after processing. The present study was aimed at production of biofuel through microalgae route using carbon capture pilot plant and exploring feasibility of scaling-up of bio-fuel production on a mega scale coal fired thermal power plant through analysis and selection of species that can grow in ash-pond area on mass scale.

Marcin Zieliński, Paulina Rusanowska, Magda Dudek et al.

Energies • 2024

Photosynthetic microbial fuel cells (pMFCs) are hybrid systems that enable simultaneous wastewater treatment under anaerobic conditions and the generation of electricity by utilizing the potential difference in the anaerobic anode chamber and the oxygenated cathode chamber. Dairy wastewater with a concentration of 2000 mg COD/L was treated in the anode of a batch pMFC. In the cathode chamber, Chlorella vulgaris or Arthrospira platensis was cultivated in synthetic medium, and next in diluted effluent from the anode chamber. The highest power density of 91 mW/m2 was generated by the pMFC with the cultivation of Arthrospira platensis. Higher values of dissolved oxygen remained during the dark phase in the cathodic medium with Arthrospira platensis cultivation than with Chlorella vulgaris. This depletion of oxygen significantly decreased voltage generation, which during the light phase increased again to the maximum values. The COD removal achieved in the anodic chamber was 87%. The efficiency of nitrogen removal in the cathode chamber during the cultivation of Arthrospira platensis and Chlorella vulgaris was about 78% and 69%, respectively. The efficiency of phosphorus removal in the cathode chamber with the cultivation of Arthrospira plantensis and Chlorella vulgaris was 58% and 43%, respectively. This study has shown that the introduction of Arthrospira platensis into the cathode chamber is more effective than that of Chlorella vulgaris.

Rajanandini Meher, Naresh Kumar Sharma

Research Journal of Chemistry and Environment • 2022

The photosynthetic microalgae can remove organic and inorganic contaminants either by accumulating it in its cells or by producing oxygen in the process of photosynthesis which can be used by bacteria to degrade organic and inorganic pollutants and hence can remove pollutants from wastewater. Though, in microbial fuel cells (MFCs), organic substrates are used as fuel which gets oxidized by microorganisms and electricity is being produced by using electrons derived by microorganisms. Therefore, integration of photosynthetic microalgae with MFCs where bacteria are being replaced by microalgae has made the entire process economically viable and energyefficient. As algae are the natural oxygen producer, no external aeration is required in photosynthetic- algal microbial fuel cells(PAMFCs) and the cultured biomass of algae can be again used as an economically feasible substrate in PAMFCs, thus reduces the energy cost. This study reviews the current development of PAMFCs and, its large scale implementation in the real world would be an ideal candidate to replace other expensive, energyconsuming and environmentally harmful system in coming decades.

R. A. Voloshin, A. M. Bozieva, B. D. Bruce et al.

Russian Chemical Reviews • 2023

Membrane electron transfer underlies the central metabolic pathways for energy conversion. The photosynthetic and respiratory electron transport chains are complex apparatuses capable of generating a transmembrane proton gradient from sunlight or chemical energy. Recent exploitation of these apparatuses as energy convertors is of interest due to the availability and eco-friendliness of the biomaterial. Devices that utilize chemotrophic microorganisms to generate electricity have been known for over one hundred years. In these systems, called microbial fuel cells (MFC), one or more microorganisms catalyze charge transfer from a consumable substrate (acetate, glucose, etc .) to the electrode. Recently, MFCs based on phototrophic organisms have been actively developed. These devices, called photosynthetic microbial fuel cells (PMFC), still resemble the conventional MFC in that they also use living microbial cells to convert chemicals to electrical energy. However, the distinction between these two classes of fuel cells is that the MFC utilizes only the chemical energy of the organic substrate. At the same time, PMFCs are also capable of using solar energy. Common to both devices is the ability to utilize intrinsic electron transfer chains of bacterial metabolism as the primary mechanism of energy conversion. The widespread and accessible solar energy may permit PMFCs based on photosynthesis to become an inexpensive and efficient method for sunlight conversion. MFCs based on heterotrophs may be more promising in wastewater remediation and other ecological applications. This article reviews the latest advances in this field and emphasizes the remaining challenges. The bibliography includes 205 references.

Zijia Zhang, Yu Zhang, Jessica Viridiana Garcia-Meza et al.

Minerals and Mineral Materials • 2023

Improving the power generation performance and pollutant removal of photosynthetic microalgae microbial fuel cells (PMMFCs) is the key to their large-scale application. In this work, microalgae (Chlorella sp. QB-102) were used as a biocatalyst in the cathode, and foam nickel modified by graphene oxide with two degrees of oxidation was used as the electrode. The results showed that the maximum power density of PMMFCs with high oxidation degree graphene oxide modified electrode (NF-GO-H) reached 209.07 mW·m-2, which was 6 times that of PMMFCs with low oxidation degree graphene oxide modified electrode (NF-GO-L), indicating that the use of the NF-GO-H electrode can effectively improve the electrical properties of PMMFCs. Simultaneously, the NF-GO-H electrode can effectively remove Cd(II), with a capacity of 6.039 g·m-2, which is twice that of the NF-GO-L electrode. Moreover, through the synergistic electrochemical action of Chlorella sp. QB-102, a large number of hydroxyl groups can be generated to convert the adsorbed Cd(II) into a more stable Cd(OH)2 precipitate. The results of this work will further expand the application of PMMFCs in power generation and heavy metal removal.

Rehab H Mahmoud, Sayeda M Abdo, Farag A Samhan et al.

Journal of Chemical Technology & Biotechnology • 2020

AbstractBACKGROUNDMicroalgae have attracted worldwide interest resulting from their extensive applications in renewable energy and biomass production. However, in algal fuel cells, photosynthetically evolved oxygen hinders the use of algal biofilms formed at the anode surface. Here, nanostructured bio‐electrochemical systems have been designed to explore the algal bio‐electrochemistry at different illumination and growth conditions.RESULTSThree algal strains were screened for their exoelectrogenic activity and the possibility of direct electron transfer to the chemically modified surfaces. After adjusting light and dark conditions and medium compositions, oxygen production within the fuel cells was regulated. At the anode surface, the obtained bioelectrochemical responses and the morphological characterizations suggested that Oscillatoria agardhii has the potential to serve as electron donor and the nanostructured surface is the final electron acceptor. To that end, dual‐chamber algal fuel cells were constructed and glucose (10 g L–1) was used as carbon source.CONCLUSIONPower density of 26.8 mW m–2 was produced using the biofilm formed by O. agardhii. Eventually, the consumption of organic waste was monitored, whereas the chemical oxygen demand removal reached 82%. © 2019 Society of Chemical Industry

Hamed Farahani, Mostafa Haghighi, Mohammad Mahdi Behvand Usefi et al.

Sustainability • 2024

Global water scarcity and pollution are among the most severe challenges, affecting the lives of over 2.2 billion people and leading to a projected water demand that will exceed supply by 40% by 2030. Even though reverse osmosis and thermal desalination are commonly adopted water governance solutions, with energy consumption rates reaching up to 10 kWh/cubic meter of water, they remain economically unfeasible for most countries. Therefore, with rapid population growth and industrialization, high operation costs further limit the adoption of the traditional water treatment technologies. However, microbial fuel cells (MFCs) and microbial desalination cells (MDCs) are an innovative solution due to their ability to treat wastewater, desalinate water, and generate bioelectricity simultaneously. The recent advancements in MFCs have enabled the achievement of over 3 W/m2 of power density, while desalination efficiencies in MDCs have surpassed 63%, reducing total energy consumption by more than 40% when compared to traditional methods. The innovative use of electrode materials, like graphene and carbon nanotubes, has led to a 40% faster electron transfer rate, further increasing the efficiency of energy recovery. Moreover, the innovative integration of artificial intelligence (AI) and machine learning (ML) optimized MFCs and MFC operations, leading to a cost reduction of up to 20% through the real-time monitoring of PMDCs. The main challenges, such as the high capital costs and membrane fouling, were also considered, with the system scalability being the recurring concern. Thus, the current reports suggest that MFCs and MDCs would reduce wastewater treatment costs by 30% if applied on a large scale in the future.

F. X. Tan, L. H. Zhang, W. F. Liu et al.

Fuel Cells • 2019

AbstractIn the technology of microbial fuel cells (MFCs) for simultaneous electricity production and wastewater purification, the electricity production of MFCs decreases when the salt concentration in the wastewater is high. Increasing the electricity production of MFCs under high salt conditions is a great challenge. This paper studies the reasons for the decline of electricity production of MFCs under high salt conditions and develops ways to increase the electricity generation. The results show that high salt inhibits the growth of electrogenic microorganisms on the anode of MFCs, thereby reducing the electricity production. Addition of ectoine, an osmotic pressure compensated solute, can increase the salt tolerance of electrogenic microorganisms, thereby increasing the electricity generation of MFCs. With the addition of 1 mmol L−1 ectoine to the substrate, the average voltage output of the MFCs based on mixed microbial flora anode was increased by 60.4% (±3.9%). Under this condition, microbial diversity analysis showed that the dominant growth and electricity production genus Acinetobacter accounted for 38.9% in the microbial community of anode biofilm.

Fatemeh Nourbakhsh, Mohsen Mohsennia, Mohammad Pazouki

Fuel Cells • 2023

AbstractThe positive effect of buffers to maintain a sui pH for microorganism growth and increase the electrolyte conductivity in microbial fuel cells (MFCs) encourages more studies on the development of new buffer solutions. The effect of types of biological buffers such as phosphate, tris, succinate, and maleate on power production in dual chamber MFC inoculated by saccharomyces cerevisiae has been examined. Electrochemical impedance spectroscopy has been used for evaluating the performance of the buffered and non‐buffered MFC systems. Considering the important impact of buffer type on the resistance of ion migration within the electrolyte and electron transport resistance of the cell components, the internal resistance of the MFC with different used buffers has been obtained and compared. According to the obtained results, the tris buffer solution showed a positive influence on the power output with a power density of 25.41% higher than phosphate.

Huichao Zhang, Qian Yan, Zhongyi An et al.

Frontiers in Microbiology • 2022

Photosynthetic microbial fuel cell (PMFC) based on algal cathode can integrate of wastewater treatment with microalgal biomass production. However, both the traditional suspended algae and the immobilized algae cathode systems have the problems of high cost caused by Pt catalyst and ion-exchange membrane. In this work, a new equipment for membrane-free PMFC is reported based on the optimization of the most expensive MFC components: the separator and the cathode. Using a revolving algae-bacteria biofilm cathode in a photosynthetic membrane-free microbial fuel cell (RAB-MFC) can obtain pollutants removal and algal biomass production as well as electrons generation. The highest chemical oxygen demand (COD) removal rates of the anode and cathode chambers reached 93.5 ± 2.6% and 95.8% ± 0.8%, respectively. The ammonia removal efficiency in anode and cathode chambers was 91.1 ± 1.3% and 98.0 ± 0.6%, respectively, corresponding to an ammonia removal rate of 0.92 ± 0.02 mg/L/h. The maximum current density and power density were 136.1 mA/m2 and 33.1 mW/m2. The average biomass production of algae biofilm was higher than 30 g/m2. The 18S rDNA sequencing analysis the eukaryotic community and revealed high operational taxonomic units (OTUs) of Chlorophyta (44.43%) was dominant phyla with low COD level, while Ciliophora (54.36%) replaced Chlorophyta as the dominant phyla when COD increased. 16S rDNA high-throughput sequencing revealed that biofilms on the cathode contained a variety of prokaryote taxa, including Proteobacteria, Bacteroidota, Firmicutes, while there was only 0.23–0.26% photosynthesizing prokaryote found in the cathode biofilm. Collectively, this work demonstrated that RAB can be used as a bio-cathode in PMFC for pollutants removal from wastewater as well as electricity generation.

Pengsha Zhao, Xinying Liu, Zheng Wang et al.

Fuel Cells • 2024

ABSTRACTAlgae–bacteria symbiosis (ABS) as a sustainable wastewater treatment process has drawn mounting attention. However, nontrivial CO2 emissions were still present in municipal wastewater treatment due to the inadequate carbon fixation efficiency of microalgae under low carbon level. The obtained UV‐induced mutant Chlorella vulgaris MIHL4 performed higher carbon fixation capability (14.5%) and biomass productivity (25.3%) with improved photosynthetic fluorescence parameters and enzyme activities compared to wild‐type C. vulgaris. Transcriptome analyses showed pathways related to the carbon fixation and carbon catabolism were significantly up‐regulated in MIHL4. Compared with ABS inoculated with wild‐type C. vulgaris, CO2 emissions were significantly reduced by 32.1%–38.3% in ABS inoculated with MIHL4, where the biomass growth, metabolic activity, and sludge granulation were enhanced. Chlorella responsible for carbon fixation was the dominant population (19.3%) in ABS inoculated with MIHL4, in which the abundance of functional microbes and genes associated with photosynthesis as well as nutrient removal increased.

Necla Altın, Başar Uyar

Biomass Conversion and Biorefinery • 2025

Abstract In this study, an algae-assisted microbial fuel cell (MFC) was developed to both treat horse manure wastewater and generate electricity. Carbon felt (CF) and graphite felt (GF) electrodes were modified with carbon nanotube (MWCNT) and nitric acid (HNO₃) to prepare different anodes and their effects on MFC performance were evaluated. The power density of 59 mW/m2 obtained with the CF-HNO₃ anode showed the highest value among all tested systems and was found to be 2.45 and 2.13 times higher than unmodified CF and GF anodes, respectively. Moreover, a 17% higher performance was achieved compared to the GF-HNO₃ anode. The higher performance of CF-HNO₃ compared to GF-HNO₃ can be attributed to the higher surface area of the carbon felt, improved proton conduction, and increased electrochemical activity after treatment with nitric acid. The modified CF-MWCNT and GF-MWCNT anodes produced power densities of 55 mW/m2 and 45 mW/m2, respectively. The Coulombic efficiency (CE) values obtained were in line with these results. The results reveal that nitric acid modification significantly increases the power output of MFCs by providing accelerated electron transfer on biofilms. This simple and effective method offers a new approach to develop low-cost and high-performance electrode materials for MFCs. Moreover, the analysis of algal biomass from the cathode chamber is in line with the existing literature and makes an important contribution towards sustainable energy solutions. The study stands out as a promising step towards the scalability and commercialization of MFCs. Furthermore, the findings can contribute to economic feasibility through low-cost modification techniques and support environmental sustainability. The findings contribute to economic feasibility and support environmental sustainability through low-cost modification techniques. Future studies can support the wider adoption of MFCs for industrial applications by investigating the effects of these modifications on long-term performance and compatibility with different wastewater types. This could accelerate the transition to sustainable energy solutions by promoting the wider use of MFCs in power generation and wastewater treatment.

Sahand Adibnia, Kevin George

Journal of Student Research • 2023

Microbial fuel cells (MFCs) are currently being researched as alternative energy sources with promising applications in wastewater treatment. However, in two-chamber designs, cathodic oxygen reduction is slow and limits MFC voltage. Biocathodes, cathodes containing microorganisms, show great promise for improving MFC performance. This study investigated how the microalgae Nannochloropsis affects cathodic oxygen reduction via a thermodynamic analysis of energy losses. Voltage, cathode pH, and cathode pO2 (partial pressure of oxygen) were measured in experimental MFCs containing Nannochloropsis biocathodes and compared to controls containing distilled water or abiotic algae media cathodes. Isolated Nanochloropsis cultures were also assayed. Under open circuit conditions, cathodic energy losses in experimental MFCs were 15% (p = 0.038597) and 19% (p = 0.042435) lower than distilled water and algae media controls, respectively. Experimental MFCs produced 73% higher power at 37% higher current density than distilled water MFCs. While the pH and pO2 of isolated Nannochloropsis cultures increased linearly each day, these measurements were constant in experimental MFC cathodes. This result suggests that participation in oxygen reduction reactions induces a change in Nannochloropsis metabolism, leading to reduced oxygen production and limiting pH changes. Taken together, this work presents a promising new type of two-chambered MFC with lower energy losses and greater power production that can also maintain a constant cathode pH and reveals a new behavior of Nannochloropsis algae in response to oxygen reduction reactions in such MFCs.

Daniele Cecconet, Arianna Callegari, Andrea Capodaglio

Energies • 2018

Groundwater contamination is a major issue for human health, due to its largely diffused exploitation for water supply. Several pollutants have been detected in groundwater; amongst them arsenic, cadmium, chromium, vanadium, and perchlorate. Various technologies have been applied for groundwater remediation, involving physical, chemical, and biological processes. Bioelectrochemical systems (BES) have emerged over the last 15 years as an alternative to conventional treatments for a wide variety of wastewater, and have been proposed as a feasible option for groundwater remediation due to the nature of the technology: the presence of two different redox environments, the use of electrodes as virtually inexhaustible electron acceptor/donor (anode and cathode, respectively), and the possibility of microbial catalysis enhance their possibility to achieve complete remediation of contaminants, even in combination. Arsenic and organic matter can be oxidized at the bioanode, while vanadium, perchlorate, chromium, and cadmium can be reduced at the cathode, which can be biotic or abiotic. Additionally, BES has been shown to produce bioenergy while performing organic contaminants removal, lowering the overall energy balance. This review examines the application of BES for groundwater remediation of arsenic, cadmium, chromium, vanadium, and perchlorate, focusing also on the perspectives of the technology in the groundwater treatment field.

Anirudh Bhanu Teja Nelabhotla, Rune Bakke, Carlos Dinamarca

Catalysts • 2019

Microbial electrosynthesis (MES) biogas upgrading is done via reduction of carbon dioxide to methane through electroactive microbial catalysis. The baseline MES mode of operation showed about a 39% increase in the methane production rate compared to the open circuit mode of operation. MES is capable of producing acetic acid at relatively more negative potential (−0.80 to –0.90 V vs. Standard Hydrogen Electrode (SHE)) than the potential at which it produces methane (−0.65 V vs. SHE). The optimum pH for enhancing the electroactive acetogens is found to be around 6.8–7.0 while a pH of around 7.0–7.5 enhances the electroactive methanogens performance. The biocathode adaptation test reveals that 45% of the methane was produced through the electrochemical pathway with a coulombic efficiency of 100% while maintaining heterotrophic efficiency above 99%.

Nuzulul Anggi Rizki, Mohammad Masykuri, Retno Rosariastuti

Journal of Biomimetics, Biomaterials and Biomedical Engineering • 2023

Ammonia is a poisonous compound that can harm fish. Fish feed and manure are the primary sources of ammonia in catfish farming ponds. High concentrations of ammonia can cause death. Therefore, it is necessary to control the presence of ammonia to minimize the potential for fish mortality. Microbial Fuel Cell (MFC) is a technology that can help with ammonia bioremediation. This study aims to analyze the effectiveness of Microbial Fuel Cell (MFC) in reducing ammonia. The research method used is an experimental research method with qualitative descriptive analysis. The research was conducted on a laboratory scale using a dual-chamber Microbial Fuel Cell (MFC) reactor connected using a salt bridge. This research was conducted with variations in the use of sticky media, including without media, with bioball, and with bioring media. The results showed that the percentage of ammonia reduction in each treatment was 94.52%, 98.09%, and 99.28%. From this research, it can be concluded that Microbial Fuel Cells (MFC) are effective in reducing ammonia.

Ardiyan Harimawan

Reaktor • 2022

As an alternative source of renewable energy that has piqued researchers’ interest, Microbial Fuel Cell’s (MFC) limitation of low power density requires further development. Various factors affect the performance, but performing all will be costly and time-consuming. Through a combination of dynamic and steady-state mathematical model modified from past research, effect of microbe types towards dynamic biofilm formation and stead-state OCV can be observed, followed by steady-state simulation to determine maximum power density and its’ corresponding voltage. Similarity with previous research has been observed, with maximum OCV of 838.93 mV achieved by heterotrophic biomass in 75-100 hours with biofilm thickness of 2.087 x 10-4 m, while generating maximum power density of 2050.12 mW//m2 and voltage of 408.16 mV. Lowest OCV value of 838.76 mV was observed in C. sporogenes in 450-475 hours with a biofilm thickness of 2.079 x 10-4 m, while the lowest value of maximum power density was observed in anaerobic microbial communities at 8.48 mW/m2 with voltage of 90.43 mV. Furthermore, it has been observed that variations with higher and lower results in higher stead-state OCV in the shortest amount of time, while increasing power density and its’ corresponding voltage. @font-face {font-family:"Cambria Math"; panose-1:2 4 5 3 5 4 6 3 2 4; mso-font-charset:0; mso-generic-font-family:roman; mso-font-pitch:variable; mso-font-signature:-536869121 1107305727 33554432 0 415 0;}@font-face {font-family:Calibri; panose-1:2 15 5 2 2 2 4 3 2 4; mso-font-charset:0; mso-generic-font-family:swiss; mso-font-pitch:variable; mso-font-signature:-469750017 -1073732485 9 0 511 0;}p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-unhide:no; mso-style-qformat:yes; mso-style-parent:""; margin:0cm; mso-pagination:widow-orphan; font-size:12.0pt; font-family:"Times New Roman",serif; mso-fareast-font-family:"Times New Roman"; mso-ansi-language:EN-US;}.MsoChpDefault {mso-style-type:export-only; mso-default-props:yes; font-size:10.0pt; mso-ansi-font-size:10.0pt; mso-bidi-font-size:10.0pt; font-family:"Calibri",sans-serif; mso-ascii-font-family:Calibri; mso-fareast-font-family:Calibri; mso-hansi-font-family:Calibri; mso-ansi-language:IN; mso-fareast-language:IN;}div.WordSection1 {page:WordSection1;}

Aldi Wahyuda Vestimarta, Irdawati Irdawati

MASALIQ • 2024

The current availability of electrical energy is not proportional to the large demand. This emphasizes the importance of saving electrical energy. To replace fossil fuel power plants that cannot be renewed. So Microbial Fuel Cells (MFC) is used, which is a technology that is able to convert chemical energy from organic matter into electrical energy through the process of oxidation and metabolism of anaerobic bacteria in electroactive biofilms at the anode. This study aims to determine the production of bioelectricity with Microbial Fuel Cell using consortium thermophilic bacteria on TMM substrate. This research was conducted in November 2023 in the microbiology laboratory, FMIPA, UNP. Data analysis was carried out descriptively by displaying images and graphs. Observation of the development of SSA 16 thermophilic bacteria was carried out for 24 hours by checking the voltage once every 2 hours. And the highest voltage result was 749 mv at the 10th hour of measurement.

Amanda Kusuma Dewi, Gunawan Djajakirana, Dwi Andreas Santosa

Jurnal Ilmu Tanah dan Lingkungan • 2020

Sampah organik dari industri tahu pada umumnya hanya dibuang ke aliran sungai di sekitarnya dan tidak dimanfaatkan oleh masyarakat. Limbah cair tahu mengandung banyak protein, sehingga dalam proses dekomposisi menghasilkan amonia yang menyebabkan bau. Kurangnya peneliti yang memahami bahwa limbah tahu juga dapat digunakan sebagai substrat dalam Sel Bahan Bakar Mikro (MFC). MFC adalah sistem atau perangkat yang menggunakan bakteri sebagai katalis untuk mengoksidasi bahan organik dan anorganik. Elektron diproduksi oleh bakteri dari substrat yang ditransfer ke anoda (kutub negatif) dan dialirkan ke katoda (kutub positif), kemudian dihubungkan oleh perangkat konduktivitas termasuk resistor atau dioperasikan di bawah muatan untuk menghasilkan listrik. Tujuan dari penelitian ini adalah mengetahui pengaruh penggunaan limbah tahu sebagai substrat dalam anoda terhadap arus listrik di MFC juga mengetahui pemodelan MFC paling efektif dan menyediakan listrik dengan arus tertinggi. Hasil penelitian menunjukkan bahwa pemodelan MFC yang dianggap paling efektif dan menghasilkan tegangan tertinggi adalah sistem dual chamber dengan Nafion. Ruang ganda MFC dengan isolat Nafion Staphylococcus saprophyticus mampu menghasilkan nilai tegangan 3,74x105 mV dan nilai kerapatan daya 2,87x104 mW m-2.

Álvaro Rodríguez del Río, Stefan Scheu, Matthias C. Rillig

Nature Communications • 2025

Abstract Anthropogenic activities impose multiple concurrent pressures on soils globally, but responses of soil microbes to multiple global change factors are poorly understood. Here, we apply 10 treatments (warming, drought, nitrogen deposition, salinity, heavy metal, microplastics, antibiotics, fungicides, herbicides and insecticides) individually and in combinations of 8 factors to soil samples, and monitor their bacterial and viral composition by metagenomic analysis. We recover 742 mostly unknown bacterial and 1865 viral Metagenome-Assembled Genomes (MAGs), and leverage them to describe microbial populations under different treatment conditions. The application of multiple factors selects for prokaryotic and viral communities different from any individual factor, favouring the proliferation of potentially pathogenic mycobacteria and novel phages, which apparently play a role in shaping prokaryote communities. We also build a 25 M gene catalog to show that multiple factors select for metabolically diverse, sessile and non-biofilm-forming bacteria with a high load of antibiotic resistance genes. Finally, we show that novel genes are relevant for understanding microbial response to global change. Our study indicates that multiple factors impose selective pressures on soil prokaryotes and viruses not observed at the individual factor level, and emphasizes the need of studying the effect of concurrent global change treatments.

Mohammad Javed Ali

Ophthalmic Plastic & Reconstructive Surgery • 2022

Purpose: To study the metagenome of the microbes present on the extubated lacrimal stents following a dacryocystorhinostomy. Methods: A prospective study was performed on 10 consecutive extubated lacrimal stents obtained for the metagenomic analysis from the patients following an endoscopic dacryocystorhinostomy. The stents were extubated at 4 weeks postoperatively under endoscopic guidance and immediately transported on ice to the laboratory. Following DNA extraction and library preparation, a whole shotgun metagenome sequencing was performed on the Illumina platform. The downstream processing and bioinformatics of the samples were performed using multiple software packaged in SqueezeMeta pipeline or MG-RAST pipeline. Results: The taxonomic hit distribution across the stent samples showed that bacteria were the most common isolates (mean, 69.70%), followed by viruses (mean, 0.02%) and archaea (0.003%). The 3 major phyla identified were Firmicutes, Actinobacteria, and Proteobacteria. The prevalent organisms include Pseudomonas aeruginosa, Staphylococcus aureus, Corynebacterium accolens, Dolosigranulum pigrum, Citrobacter koserii, Staphylococcus epidermidis, E. coli, and Hemophilus influenza. The functional subsystem profiling demonstrated microbial genes associated with metabolism, cellular, and information processing. The functional subsystem categories were metabolism involving carbohydrates, amino acids, DNA and RNA, cell wall or cell capsule biogenesis, membrane transport, virulence, and defense mechanisms. Conclusions: The present study is the first whole metagenome sequencing of the microbes isolated from the extubated lacrimal stents. The stents harbor diverse microbial communities with distinct ecosystem dynamics. Further studies on microbes-host interactions in the early postoperative period would provide valuable insights.

Gabriele Andrea Lugli, Marco Ventura

Microbiome Research Reports • 2022

Next-generation sequencing technologies allow accomplishing massive DNA sequencing, uncovering the microbial composition of many different ecological niches. However, the various strategies developed to profile microbiomes make it challenging to retrieve a reliable classification that is able to compare metagenomic data of different studies. Many limitations have been overcome thanks to shotgun sequencing, allowing a reliable taxonomic classification of microbial communities at the species level. Since numerous bioinformatic tools and databases have been implemented, the sequencing methodology is only the first of many choices to make for classifying metagenomic data. Here, we discuss the importance of choosing a reliable methodology to achieve consistent information in uncovering microbiomes.

TzeHau Lam, Dillon Chew, Helen Zhao et al.

Frontiers in Microbiology • 2022

Microbiomes on surfaces in kindergartens, the intermediate transfer medium for microbial exchange, can exert significant impact on the hygiene and wellbeing of young children, both individually and as a community. Here employing 2bRAD-M, a novel species-resolved metagenomics approach for low-biomass microbiomes, we surveyed over 100 samples from seven frequently contacted surfaces by children, plus individual children’s palms, in two kindergartens. Microbiome compositions, although kindergarten-specific, were grouped closely based on the type of surface within each kindergarten. Extensive microbial admixture were found among the various sampled sites, likely facilitated by contact with children’s hands. Notably, bacterial species with potential human health concerns and potentially antibiotic-resistant, although found across all sampled locations, were predominantly enriched on children’s hands instead of on the environmental sites. This first species-resolved kindergarten microbiome survey underscores the importance of good hand hygiene practices in kindergartens and provides insights into better managing hygiene levels and minimizing spread of harmful microbes in susceptible indoor environments.

Rabeay Y.A. Hassan, Ferdinando Febbraio, Silvana Andreescu

Sensors • 2021

Microbial electrochemical systems are a fast emerging technology that use microorganisms to harvest the chemical energy from bioorganic materials to produce electrical power. Due to their flexibility and the wide variety of materials that can be used as a source, these devices show promise for applications in many fields including energy, environment and sensing. Microbial electrochemical systems rely on the integration of microbial cells, bioelectrochemistry, material science and electrochemical technologies to achieve effective conversion of the chemical energy stored in organic materials into electrical power. Therefore, the interaction between microorganisms and electrodes and their operation at physiological important potentials are critical for their development. This article provides an overview of the principles and applications of microbial electrochemical systems, their development status and potential for implementation in the biosensing field. It also provides a discussion of the recent developments in the selection of electrode materials to improve electron transfer using nanomaterials along with challenges for achieving practical implementation, and examples of applications in the biosensing field.

Tanja Vidakovic-Koch

ECS Meeting Abstracts • 2023

The most popular technique for characterizing various electrochemical devices such as fuel cells, water electrolysis or batteries is electrochemical impedance spectroscopy (EIS). However, due to the coupling of dynamic phenomena with similar time constants, EIS often fails to separate the contributions of individual processes to overall performance losses. In this case, obtaining useful information from the EIS spectra can be be difficult and the interpretation of the observed patterns is unclear. In this talk, I show that new dynamical methods based on the use of nonlinearities in the system response (nonlinear frequency response analysis (NFRA) [1]), non-electrical inputs (concentration-alternating frequency response analysis (cFRA) [2]), or data-driven analyses (Loewner framework [3]) can provide additional information for understanding electrochemical conversion processes. Our current examples are related to the study of polymer electrolyte membrane electrolysis and polymer electrolyte membrane fuel cell. References [1] Vidaković-Koch T., Miličić, T., Živković, L.A., Chan, H.S., Krewer, U., Petkovska, M., (2021) Nonlinear Frequency Response Analysis: A Recent Review and Perspectives, Current Opinion in Electrochemistry, 100851. [2] Sorrentino, A., Sundmacher, K. & Vidaković-Koch, T. (2020). Polymer Electrolyte Fuel Cell Degradation Mechanisms and Their Diagnosis by Frequency Response Analysis Methods: A Review. Energies, 13(21), 5825. [3] Antoulas, A. C., Lefteriu, S., and Ionita, A. C., (2017) A tutorial introduction to the Loewner framework for model reduction in Model Reduction and Approximation, Eds: P. Benner, A Cohen, M. Ohlberger, K. Willcox, Siam Comupational Science and Engineering, Chapter 8, pp. 335–376.

Yucel KOC, Huseyin AVCİ

Eskişehir Osmangazi Üniversitesi Mühendislik ve Mimarlık Fakültesi Dergisi • 2022

ecently increasing attention has been paid to the development of highly sensitive and selective electrochemical sensors for accurate and cost-effective detection in various fields. In this study, gold nanoparticles (AuNPs) were electro-deposited onto screen printed gold electrode (SPGE) surfaces at different times to determine the optimum modification conditions. Determining the optimum modification for the SPGE surface, AuNP modification under −0.3 V potential with 2 mM HAuCl4 (in 0.5 M H2SO4) solution were investigated. In this case, for the optimum AuNP modification, electrochemical impedance spectroscopy (EIS) analysis was performed at the following deposition times: 30, 60, 90, 120, and 150 s. As a result of modeling the Nyquist graph obtained in the range of 10 kHz to 0.1 Hz with the EIS analysis based on the equivalent circuit model, the outcomes for each modification time were analyzed. After the modification with AuNPs, scanning electron microscope (SEM) images of the SPGE surfaces were discussed. As a result, the optimum deposition time was determined as 90 s by the analysis. This study can be used for electrochemical investigation and target detection in complex media in terms of AuNPs on SPGE surfaces with a detailed perspective for nanoparticle deposition.

Franz Schauer

Journal of Applied Physics • 2020

Organic electronic applications are envisioned to address broad markets, which includes flexible displays, electronic papers, sensors, disposable and wearable electronics, and medical and biophysical applications, leading to a tremendous amount of interest from both academia and industry in the study of devices. These fields of science and technology constitute interdisciplinary fields that cover physics, chemistry, biology, and materials science, leading, as a wanted output, to the elucidation of physical and chemical properties, as well as structures, fabrication, and performance evaluation of devices and the creation of new knowledge underlying the operation of organic devices using new synthesized organic materials—organic semiconductors. We testify the situation when the available organic electronic applications sometimes lack a theoretical background. The cause may be the complicated properties of disordered, weak bounded, molecular materials with properties different from their inorganic counterparts. One of the basic information-rich resources is the electronic structure of organic semiconductors, elucidated by the methods, hardly possible to be transferred from the branch of inorganic semiconductors. Electrochemical spectroscopic methods, in general, and electrochemical impedance spectroscopy, in particular, tend and seem to fill this gap. In this Perspective article, the energy resolved-electrochemical impedance spectroscopic method for electronic structure studies of surface and bulk of organic semiconductors is presented, and its theoretical and implementation background is highlighted. To show the method’s properties and strength, both as to the wide energy and excessive dynamic range, the basic measurements on polymeric materials and D–A blends are introduced, and to highlight its broad applicability, the results on polysilanes degradability, gap engineering of non-fullerene D–A blends, and electron structure spectroscopy of an inorganic nanocrystalline film are highlighted. In the outlook and perspective, the electrolyte/polymer interface will be studied in general and specifically devoted to the morphological, transport, and recombination properties of organic semiconductors and biophysical materials.

Serban Lepadatu

Journal of Applied Physics • 2020

This work discusses the design and testing of a new computational spintronics research software. Boris is a comprehensive multi-physics open-source software, combining micromagnetics modeling capabilities with drift-diffusion spin transport modeling and a heat flow solver in multi-material structures. A multi-mesh paradigm is employed, allowing modeling of complex multi-layered structures with independent discretization and arbitrary relative positioning between different computational meshes. Implemented micromagnetics models include not only ferromagnetic materials modeling, but also two-sublattice models, allowing simulations of antiferromagnetic and ferrimagnetic materials, fully integrated into the multi-mesh and multi-material design approach. High computational performance is an important design consideration in Boris, and all computational routines can be executed on graphical processing units (GPUs), in addition to central processing units. In particular, a modified 3D convolution algorithm is used to compute the demagnetizing field on the GPU, termed pipelined convolution, and benchmark comparisons with existing GPU-accelerated software Mumax3 have shown performance improvements up to twice faster.

Ravi Jenani, Arjunan Babu Ponnusami

REVIEWS ON ADVANCED MATERIALS SCIENCE • 2025

Abstract In the era of climate change and the global energy crisis, alternate energy sources are desirable to replace carbon and fossil fuels. Microbial fuel cells (MFCs) are distinctive because of their ability to transform organic waste into electricity through bio-electrochemical reactions. The current study investigates the preparation and application of zinc oxide nanoparticles (ZnO NPs) and sulfonated ZnO nanoparticles (SZnO NPs) incorporated in polyvinyl alcohol (PVA) membrane as a separator in dual-chambered MFC for Tannery wastewater treatment. Characterization of these membranes shows that the NPs are well dispersed onto the polymer base. The synthesized sulfonated membrane has better water uptake capacity (90.5%) and oxygen mass transfer coefficient (1.09 × 10−6 cm·s−1) than the Nafion membrane water uptake capacity (21.8%) and oxygen mass transfer coefficient (2.68 × 10−4 cm·s−1). Different amounts of NPs were incorporated into the polymer base to optimize the membrane performance by increasing the proton conductivity for better operation in MFC with reduced biofouling. When the MFC was operated with tannery wastewater, a maximum power density of 160.554 mW·m−2 and a chemical oxygen demand removal of 84.618% were obtained using the PVA–SZnO membrane with reduced biofouling. This observation proves that the sustainable and affordable PVA–SZnO membrane can be used as a separator for MFC and for treating Tannery wastewater.

Hongjian Lin, Sarah (Xiao) Wu, Jun Zhu

Applied Sciences • 2018

The model proposed in this study was based on the assumption that the biomass attached to the anode served as biocatalysts for microbial fuel cell (MFC) exoelectrogenesis, and this catalytic effect was quantified by the exchange current density of anode. By modifying the Freter model and combining it with the Butler–Volmer equation, this model could adequately describe the processes of electricity generation, substrate utilization, and the suspended and attached biomass concentrations, at both batch and continuous operating modes. MFC performance is affected by the operating variables such as initial substrate concentration, external resistor, influent substrate concentration, and dilution rate, and these variables were revealed to have complex interactions by data simulation. The external power generation and energy efficiency were considered as indices for MFC performance. The simulated results explained that an intermediate initial substrate concentration (about 100 mg/L under this reactor configuration) needed to be chosen to achieve maximum overall energy efficiency from substrate in the batch mode. An external resistor with the value approximately that of the internal resistance, boosted the power generation, and a resistor with several times of that of the internal resistance achieved better overall energy efficiency. At continuous mode, dilution rate significantly impacted the steady-state substrate concentration level (thus substrate removal efficiency and rate), and attached biomass could be fully developed when the influent substrate concentration was equal to or higher than 100 mg/L at any dilution rate of the tested range. Overall, this relatively simple model provided a convenient way for evaluating and optimizing the performance of MFC reactors by regulating operating parameters.

Rauno Lust, Jaak Nerut, Kuno Kasak et al.

Water • 2020

Assessments of groundwater aquifers made around the world show that in many cases, nitrate concentrations exceed the safe drinking water threshold. This study assessed how bioelectrochemical systems could be used to enhance nitrate removal from waters with low organic carbon concentrations. A two-chamber microbial electrosynthesis cell (MES) was constructed and operated for 45 days with inoculum that was taken from a municipal wastewater treatment plant. A study showed that MES can be used to enhance nitrate removal efficiency from 3.66% day−1 in a control reactor to 8.54% day−1 in the MES reactor, if a cathode is able to act as an electron donor for autotrophic denitrifying bacteria or there is reducing oxygen in a cathodic chamber to favor denitrification. In the MES, greenhouse gas emissions were also lower compared to the control. Nitrous oxide average fluxes were −639.59 and −9.15 µg N m−2 h−1 for the MES and control, respectively, and the average carbon dioxide fluxes were −5.28 and 43.80 mg C m−2 h−1, respectively. The current density correlated significantly with the dissolved oxygen concentration, indicating that it is essential to keep the dissolved oxygen concentration in the cathode chamber as low as possible, not only to suppress oxygen’s inhibiting effect on denitrification but also to achieve better power efficiency.

M. Elakkya

Advances in Nonlinear Variational Inequalities • 2025

This work describes the entrapped-cell photobioreactor Rhodopseudomonas palustris CQK 01 in a multiphase flow transport model. The model uses two relevant non-linear reaction-diffusion equations to represent the substrate and product concentrations inside the gel granules for biochemical interactions in the photobioreactor. The Akbari-Ganji and homotopy perturbation methods are used to obtain simple approximation analytical expressions for the concentrations, liquid and gas phases in the steady-state condition. The analytical and the numerical results are compared to verify the efficiency. The analytical data and the simulated results agreed well for all concentrations. Furthermore, two limiting scenarios, zero and first-order kinetics, were used, and the results were examined. The parameters in our proposed methods can be utilized to simulate the dynamic performance of a system, as evidenced by the close agreement between the simulated and analytical data.

Tamás Koncsos

Periodica Polytechnica Civil Engineering • 2020

The efficient operation of activated sludge type wastewater treatment plants is an ongoing topic for the utility providers, where electric energy consumption shares are high, giving cca. 30 % of total operational costs. Intervention methods for intensification include fine tuning of aeration settings, sludge removal and the adjustment of recirculation rates. In order to analyze the effects of various process control strategies, activated sludge models (ASM) are used for the purpose of biokinetic modeling. In practice, most model simulators do not incorporate optimization and necessary auto-calibration of the latter, due to high computational demand of timeseries evaluation. In this paper, a new mathematical model is presented, which makes biokinetic simulations suitable for the use in decision support systems. Namely, the ASM model is approximated with a computanional inexpesive quadratic model solution, fed into a set of mass-balance corrected neural networks. Cost optimization is achieved with Markov decision process model. The developed method was illustrated for a case of Hungarian, large wastewater treatment plant. It was proven, the model is able to find better aeration schemes for the plant in aspect of cost of operation and nitrogen removal efficiency. The model can be used to find cost-optimal policies under arbitrary defined conditions. As a benefit, results can be implemented into industrial logic controllers.

Weiwei Jin

Research in Health Science • 2024

In this study, the metabolic regulation mechanism of microorganisms in bioreactor was discussed, and a series of optimization strategies were proposed based on this. The key effects of metabolic regulation on the performance of bioreactors were revealed through the overview of microbial metabolic pathways and the analysis of regulatory mechanisms. In view of this, the optimization strategy based on metabolic regulation was proposed from the aspects of metabolic engineering transformation, genetic engineering technology application, metabolic pathway reconstruction and optimization. At the same time, the operating conditions of the reactor, such as temperature, pH value, dissolved oxygen, substrate concentration and mixing effect were optimized in detail. In terms of reactor design and scale-up strategy, the scale effect, reactor configuration and flow field optimization, and heat and mass transfer enhancement technology were mainly considered. This study provides important theoretical and practical guidance for the improvement of bioreactor performance and the progress of biotechnology industry.

Grace L. Baldwin, Robert M. Stwalley

Sustainability • 2022

The United Nations Food and Agriculture Organization reports approximately 1.9 million hectares (Mha) total of potential irrigatable lands in Ghana. However, the total water-managed area in the country was estimated to be only approximately 30,900 hectares (ha) in 2000 or 1.7% of the possible area. The government ultimately intends to add a total irrigatable area of 500,000 ha or more, thereby increasing the total coverage to 28% of the country’s potential. This would be beneficial because Ghana is not currently agriculturally independent and seeks to make substantial efforts in the scale-up of irrigation technologies to decrease the country’s reliance on the importation of agricultural goods. Unfortunately, the state of available technical literature for the very specific subject of agricultural water resources in a small African country is limited and generally only thinly published. A successful review of the published literature was conducted by expanding the search parameters until an adequate level of material became available to accurately describe the situation. The adaptive review process to access progressively more relevant information is presented in the methodology. The country’s total water withdrawal was quantified. The constraints on water resource development within Ghana’s socio-political environment were examined, and opportunities for technical improvement were identified. If well-managed, the country’s surface water and largely untapped groundwater systems are sufficient to meet most domestic and irrigation purposes. This analysis should provide significant aid to the government, non-governmental organizations, and aid agencies working to improve agricultural productivity via the scale-up of irrigation systems in Ghana and other similar countries.

Harriet Koorts, Harry Rutter

Health Research Policy and Systems • 2021

AbstractDespite a number of important global public health successes, for many health behaviours there is a continued lack of interventions that have been sufficiently scaled up to achieve system-wide integration. This has limited sustainable and equitable population health improvement. Systems change plays a major role in the relation between implementation processes and at-scale institutionalisation of public health interventions. However, in research, systems approaches remain underutilised in scaling up. Public health scale-up models have typically centred on intervention replication through linear expansion. In this paper, we discuss current conceptualisations and approaches used when scaling up in public health, and propose a new perspective on scaling that shifts attention away from the intervention to focus instead on achieving the desired population-level health outcomes. In our view, ‘scaling up’ exists on a continuum. At one end, effective scaling can involve a linear, intervention-orientated expansive approach that prioritises the spread of evidence-based interventions into existing systems in order to drive expansion in the application of that intervention. At the other end, we contend that scale-up can sit within a complex systems paradigm in which interventions are conceptualised as events in systems. In this case, implementation and scale-up activities should focus on generating changes within the system itself to achieve the desired outcome. This we refer to as ‘systems-orientated scale-up’ to achieving population health improvement, which can complement traditional approaches in relevant situations. We argue that for some health behaviours, our proposed approach towards scaling up could enhance intervention implementation, sustainability and population health impact.

,

European Journal of Public Health • 2020

Abstract Objectives Non-communicable diseases (NCD) are a major challenge for health systems across the globe. Although effective interventions for prevention, detection and control exist, these do not reach all people in need, especially the poor and most vulnerable. Scale-up strategies are developed to increase universal access to those interventions, addressing demand-side and supply-side barriers and to facilitate integration in the health system. While there are useful frameworks to conceptualise and operationalise scale-up of NCD interventions, there is a knowledge gap on what and how to evaluate. This session addresses that knowledge gap, presenting evaluation methods for scale-up from four large multi-country research projects. The objectives are: To increase knowledge on four dimensions of scale-up evaluation: 1) contextualisation of methods; 2) implementation evaluation; 3) cost-evaluation and 4) use of health information systemsTo present methods and results of implementation research on NCDs as an example for other chronic diseasesTo illustrate how contextualisation, implementation and evaluation varies across different stages of scale-upTo stimulate learning by experience through small-group discussion with session participants This workshop provides added value through the four coherent presentations combined with small group interactions on the same topics. It allows the audience to link the case study lessons to their own research and wider application. Format Four different elements of scale-up evaluation are addressed: 1) Contextualisation of evaluation methods from a common framework; 2) Implementation evaluation at operational level; 3) Cost-evaluation of NCD interventions; and 4) Large-scale evaluation through routine health information systems (HIS). Case studies from four large-scale Horizon2020 funded research projects in 14 countries in Europe, Africa and Asia will be presented, each case focusing on one dimension. Cross-cutting themes of adaptation and transferability of methods will also be addressed. After the presentations, there will be an interactive session to promote experience-based learning in small-group discussions. Presentations Self-Management Approach and Reciprocal Learning for Type 2 Diabetes (SMART2D)Scaling-up Packages of Interventions for cardiovascular disease prevention in Europe and Sub-Saharan Africa (SPICES)Scaling-Up NCD Interventions in South-East Asia (SUNI-SEA)The Scale-Up of Diabetes and Hypertension Care (SCUBY) The presentations will provide the introduction to subsequent small-table discussions, around the following questions: How to measure and monitor implementation and outcome of intervention scale-up?How to generate transferrable lessons from cross-country studies?How to conduct cross-setting evaluation of the effect and cost of NCD interventions? Key messages The global scale-up of NCD interventions calls for robust evaluation methods of effect, implementation and cost. Evaluation methods need to be fit to the country context and health information systems.

V Buffel

European Journal of Public Health • 2020

Abstract The SCUBY project aims to (1) change the organization of primary health care for diabetes and hypertension in order to (2) improve the outcome of chronic care in three countries (Belgium-Slovenia-Cambodia). These two aims require two types of data, namely data on the organization of care and data on the chronic illness outcomes. It can however be challenging to (1) gather all these data (from various sources) on both the organization and outcomes and (2) create cross-culturally valid datasets. The presentation will present the strategy of SCUBY to gather data and discuss the issues of cross-cultural validity.

Enza Palma, Matteo Daghio, Anna Espinoza Tofalos et al.

Environmental Science: Water Research & Technology • 2018

High-rate anaerobic oxidation of toluene was achieved in a continuous-flow bioelectrochemical system.