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Discover insights from thousands of peer-reviewed papers on microbial electrochemical systems
Discover insights from thousands of peer-reviewed papers on microbial electrochemical systems
K. Ptaszkowski, R. Zdrojowy, Lucyna Słupska et al.
European Journal of Physical and Rehabilitation Medicine • 2017
BACKGROUND Menopausal women often experience the prolapse of the uterus, bladder and rectum resulting from the failure and weakening of the pelvic floor muscles (PFM). Strengthening of the PFM through the standard exercises is recognized as an effective way of preventive measures and conservative treatment of the symptoms listed above, but still need to be improved. AIM The goal was the objective assessment of resting and functional bioelectrical activity of PFM in women during menopause and its comparison in three different positions of the pelvis: anterior pelvic tilt - position 1 (P1), posterior pelvic tilt - position 2 (P2), and neutral pelvic tilt - position 3 (P3). DESIGN Prospective, cross-sectional observational study. SETTING Department and Clinic of Urology of a University Hospital. POPULATION The target group of this study included women in the menopausal period (inpatient and outpatient). METHODS The study evaluating resting and functional activity of the PFM depending on the orientation of pelvis. Bioelectric activity was assessed with an electromyographic instrument (sEMG) and endovaginal electrodes. The inclination angle was measured with an inclinometer. The comparisons of results between the values obtained in P1, P2, and P3 were performed using one-way Analysis of Variance (ANOVA). RESULTS One hundred thirty-one registered for the study were screened for inclusion and exclusion criteria and on the basis of the results 82 participants were enrolled for analysis. The highest mean resting activity of sEMG PFM (µV) was observed in P2 and it amounted to 11.6 µV (SD=5.5 µV) in P1 the value equaled 9.8 µV (SD=4.8 µV) and P3-9.0 µV (SD=4.2 µV). The results revealed a significant statistical difference (main effect: P=0.0007). Considering the functional sEMG activity of PFM (µV), the highest mean value was recorded in P2. CONCLUSIONS Posterior pelvic tilt position determines higher resting and functional bioelectric activity of PFM. Additionally, electromyographic activity of PFM increases during the pelvic movement backwards. CLINICAL REHABILITATION IMPACT These positions should be implemented in therapy in order to improve the effectiveness of the effect on the pelvic floor.
Amir Javan-Khoshkholgh, A. Farajidavar
Sensors • 2019
High-resolution (HR) mapping of the gastrointestinal (GI) bioelectrical activity is an emerging method to define the GI dysrhythmias such as gastroparesis and functional dyspepsia. Currently, there is no solution available to conduct HR mapping in long-term studies. We have developed an implantable 64-channel closed-loop near-field communication system for real-time monitoring of gastric electrical activity. The system is composed of an implantable unit (IU), a wearable unit (WU), and a stationary unit (SU) connected to a computer. Simultaneous data telemetry and power transfer between the IU and WU is carried out through a radio-frequency identification (RFID) link operating at 13.56 MHz. Data at the IU are encoded according to a self-clocking differential pulse position algorithm, and load shift keying modulated with only 6.25% duty cycle to be back scattered to the WU over the inductive path. The retrieved data at the WU are then either transmitted to the SU for real-time monitoring through an ISM-band RF transceiver or stored locally on a micro SD memory card. The measurement results demonstrated successful data communication at the rate of 125 kb/s when the distance between the IU and WU is less than 5 cm. The signals recorded in vitro at IU and received by SU were verified by a graphical user interface.
J. Kabaciński, A. Fryzowicz, A. Błaszczyk et al.
Sports Biomechanics • 2020
ABSTRACT In sweep rowers, the lower extremities muscle strength translates into the driving force of the boat. Therefore, isokinetic assessment of muscle torque is used by coaches as an indicator of the level of athletes’ preparation for competitions. A total of 22 elite sweep rowers performed an isokinetic test of knee joint flexors and extensors, and a test on an asymmetric ergometer with the electromyography measures. Significantly higher quadriceps peak torque was shown during the beginning than the end of the preparatory period (p < 0.05). However, there was no significant knee peak torque difference between the lower extremities (p = 0.398). In the case of the electromyography test of quadriceps, hamstrings and lumbar erector spinae, analysis demonstrated significant bioelectrical activity differences between the sides (p < 0.05). Lower values of quadriceps peak torque at the end of the preparatory period may result from a decrease in the number of power training units during the entire preparatory period. A similar muscle strength between both lower extremities seems to be the correct result in the context of injury prevention. In turn, significant bioelectrical activity differences between the sides possibly are associated with the asymmetric movement pattern in sweep rowers.
M. Vorkapić, A. Savić, M. Janković et al.
PLOS ONE • 2020
Background Clinical and animal studies have found that anxiety and depression are significantly more common after acute myocardial infarction (AMI). The medial prefrontal cortex (PFC) has a dual role: in higher brain functions and in cardiovascular control, making it a logical candidate for explaining the perceived bidirectional heart-brain connection. We used parallel Electrocardiography (ECG) and Electrocorticography (ECoG) registration to investigate AMI-induced changes in medial PFC bioelectrical activity in a rat model of AMI. Materials and methods Adult male Wistar albino rats were used in the study. Gold-plated recording electrodes were implanted over the frontal cortex for ECoG recording. ECG was recorded via two holter electrodes attached on the skin of the back fixed in place by a jacket. Induction of AMI was performed by isoprenaline (150 mg/kg, i.p.). ECoG and ECG signals were registered at baseline, during 3 hours after isoprenaline administration and at 24 hours after isoprenaline administration. Results Significant increases of theta, alpha, and beta electroencephalographic (EEG) band power were observed in different time intervals after isoprenaline administration. Significant increase of theta band peak frequency was also observed during the first hour after isoprenaline administration. No statistically significant differences in band-power activity were found between the pre-isoprenaline measurements and 24 hours after administration. Conclusion Our results demonstrate significant increases in EEG band power of alpha beta and theta bands during isoprenaline-induced AMI model. These are the first findings to connect heart damage during isoprenaline- induced AMI to disturbances in the cortical bioelectrical activity.
Yosuke Yamada, T. Yoshida, H. Murakami et al.
Scientific Reports • 2022
The phase angle (PhA), measured via bioelectrical impedance analysis, is considered an indicator of cellular health, where higher values reflect higher cellularity, cell membrane integrity, and better cell function. This study aimed to examine the relationship between PhA and exercise habits or objectively measured physical activity. We included 115 people aged 32–69 years. The body composition and PhA were measured using a bioelectrical impedance device. Physical activity and sedentary behavior (SB) were assessed using a triaxial accelerometer. Exercise habits were also obtained through structured interviews, and participants were categorized into the no exercise habit (No-Ex), resistance training exercise habit (RT), or aerobic training exercise habit (AT) groups. Objectively measured moderate-to-vigorous physical activity or step count significantly correlated with PhA, independent of age, sex, height, percent body fat, body cell mass, and leg muscle power. In contrast, SB was not significant determinants of PhA. People who exercised regularly (RT or AT) had significantly higher PhA values than did those in the No-Ex group. Furthermore, the PhA was not significantly different between the RT and AT groups. Regularly engaging in exercise with moderate-to-vigorous intensity may improve or maintain muscle cellular health and muscle quality.
A. Parise, G. N. Reissig, Luis Felipe Basso et al.
Frontiers in Plant Science • 2021
In our study, we investigated some physiological and ecological aspects of the life of Cuscuta racemosa Mart. (Convolvulaceae) plants with the hypothesis that they recognise different hosts at a distance from them, and they change their survival strategy depending on what they detect. We also hypothesised that, as an attempt of prolonging their survival through photosynthesis, the synthesis of chlorophylls (a phenomenon not completely explained in these parasitic plants) would be increased if the plants don’t detect a host. We quantified the pigments related to photosynthesis in different treatments and employed techniques such as electrophysiological time series recording, analyses of the complexity of the obtained signals, and machine learning classification to test our hypotheses. The results demonstrate that the absence of a host increases the amounts of chlorophyll a, chlorophyll b, and β-carotene in these plants, and the content varied depending on the host presented. Besides, the electrical signalling of dodders changes according to the species of host perceived in patterns detectable by machine learning techniques, suggesting that they recognise from a distance different host species. Our results indicate that electrical signalling might underpin important processes such as foraging in plants. Finally, we found evidence for a likely process of attention in the dodders toward the host plants. This is probably to be the first empirical evidence for attention in plants and has important implications on plant cognition studies.
Łukasz Oleksy, A. Mika, I. Sulowska-Daszyk et al.
International Journal of Environmental Research and Public Health • 2021
The aim of the study was to determine the between-trial and between-day reliability of the Glazer protocol and our multi-activity surface electromyography (sEMG) measurement protocol for pelvic floor muscle (PFM) evaluation. The bioelectrical activity of PFM was collected using an endovaginal electrode in 30 young, Caucasian, nulliparous women (age 22–27, 168.6 ± 5.1 cm, 57.1 ± 11.8 kg). The between-trial and between-day reliability of the original Glazer protocol and the new multi-activity sEMG protocol were assessed during the following phases: pre-baseline rest, phasic (flick) contractions, tonic contractions, endurance contraction, and post-baseline rest. The Glazer protocol was characterized by poor and moderate measurement reliability. The time-domain parameters for the rise and fall of the signal amplitude and median frequency showed poor between-trial and between-day reliability. The mean and peak amplitudes indicated mainly good between-trial and moderate between-days reliability. Our protocol showed moderate to excellent reliability of both time-domain and quantitative parameters of muscle recruitment. In our protocol, the frequency-domain parameters describing muscle fatigue demonstrated much higher reliability than in the case of the Glazer protocol. The most important information obtained in this study was the significant improvement of diagnostic validity in PFM bioelectrical activity evaluation. The higher reliability of our sEMG protocol compared to original Glazer protocol allowed us to suggest that protocol modifications and changes in sEMG signal processing methods were effective in the improvement of PFM assessment quality. The new parameters calculated from the sEMG signal proposed in our sEMG protocol allowed us to obtain additional clinically important information about PFM dysfunctions regarding specific deficits of muscle contraction such as decrease in muscle strength; endurance or coordination related to, e.g., stress urinary incontinence; or pelvic floor muscle imbalance after childbirth.
K. Kalitin, G. V. Pridvorov, A. Spasov et al.
Journal of Volgograd State Medical University • 2022
Since ischemic stroke is an extremely common and dangerous pathology, it is important to use drugs with neuroprotective activity. The depth and degree of brain damage due to ischemia are reflected in its bioelectrical activity. This makes it possible to use the electrocorticography or intracranial electroencephalography (EEG) as a tool for evaluating the effectiveness of neuroprotective therapy. In the present study the neuroprotective properties of the experimental compound RU-1205 and the kappa-opioid agonist butorphanol were analyzed. The neuroprotective effect of the substances was assessed by measuring the extent of the neurological deficit and the changes in bioelectrical activity of the ischemic brain of rats. Compound RU-1205 (10 mg/kg, i.v.) as well as the reference drug butorphanol (2,5 mg/kg, i.v.) restored to normal neurological status and power of the EEG signal in delta and theta frequency bands.
Dariia Liashko
ScienceRise • 2020
The object of the study. Experimental research of music therapy methods. The problem to be solved. Determining the influence of selected musical composition of the audible frequency spectrum on the bioelectrical activity of students' brains, in particular alpha-, beta- and theta-rhythms. Main scientific results. The dependence of the influence on the bioelectrical activity of the brain of the compositions of the three frequency bands both individually and the composition as a whole is revealed. The dependence of alpha, beta and theta rhythms is shown. The area of practical use of the research results. Medical institutions specializing in the treatment of disorders of the central nervous system, organic brain damage, stress, and its effective psychological rehabilitation. An innovative technological product. A technique of music therapy that allows to determine how different frequency ranges affect the bioelectrical activity of the human brain. The area of application of an innovative technological product. Clinical practice of using a music therapy.
I. A. Kostenko, M. V. Aleksandrov, V. S. Chernyi
Toxicological Review • 2021
The aim of the stady wos to investigate the mechanisms of suppression of cerebral bioelectrical activity under adverse effects caused by neurotoxicants using inhalation anesthesia with sevoflurane. The research included 19 cases (male/female 12/7, aged 19—55, BMIs under 35) with intracerebral tumors. Patients were under medical observation and neurosurgical treatment. Invasive procedures were carried out under sevoflurane-based general anesthesia with a dose of anesthetic varying from 0,8 to 1,3 MAC (minimum alveolar concentration). Technologically advanced neurosurgical procedures involved neurophysiological polymodal monitoring, which included EEG and ECoG testing. Probit analysis results showed that, with cerebral cortex bioelectrical activity suppression index equal to 32±8%, nearly half the cases displayed a formation of an «outburst-suppression» type of pattern on the scalp EEG. The condition for half the cases displaying a formation of this type of periodic pattern is the suppression index equaling 58±7% on ECoG. Space-and-time evolution of suppression patterns, formed on the cerebral cortex, is the main reason for persistence of uninterrupted activity on EEG. The obtained results allow to further define principles of neurodynamics, which apply to acute intoxication with neurotoxicants. With regard to relative similarity of intoxication-induced coma cases, registration of periodic EEG patterns even with a low suppression index indicates a more severe form of cerebral insufficiency.
Vilma Kisnierienë, Vidmantas Sakalauskas
Open Life Sciences • 2007
Abstract Aluminium induced membrane potential (Em) changes and potential changes during repolarization phase of the action potential (AP) in the internodal cells of Nitellopsis obtusa after blocking H+-ATPase activity by DCCD were investigated. Micromolar concentrations of DCCD are sufficient to give complete and irreversible inhibition of proton pumping. The membrane potential was measured by conventional glass-microelectrode technique. We found that the half-amplitude pulse duration differs significantly between standard conditions, after DCCD application, and after H+-ATPase blocking and subsequent Al3+ treatment: 4.9, 7.7 and 17.2 seconds, respectively. We propose that in the short term (2 hours) treatment of Al3+, the decrease in membrane potential was compensated for by H+-ATPase activity. Blocking H+-ATPase activity by DCCD can enhance the influence of Al3+ on the bioelectrical activity of cell membranes.
David A. Finkelstein, L. Tender, J. Zeikus
Environmental Science & Technology • 2006
The benthic microbial fuel cell (BMFC) generates power by coupling oxidation of fuels naturally residing in marine sediments with reduction of oxygen in overlying waters. A central feature of BMFCs is spontaneous colonization of the anode by mineral-reducing microorganisms indigenous to marine sediments that catalyze the power-generating anodic reactions. Described here is a preliminary investigation of how the anode potential affects this feature. Different oxidative potentials were applied to a set of anodes under conditions known to promote anode enrichment of acetate oxidizing/mineral reducing microorganisms. In-situ analysis of current, acetate consumption, and reducing ability of the anode colonies suggest thatthe microorganisms conserve a significant portion (as much as 95%) of potential energy liberated from oxidation of acetate and reduction of the anode for their own metabolic benefit. The implication of this result with respect to BMFCs, and other MFCs utilizing electrode-reducing microbial catalysts, is that although the microorganisms enable long-term stability of such fuel cells, they may significantly impact efficiency of power output per equivalent of fuel consumed.
A. Darwish, M. Elgenedy, S. Finney et al.
IEEE Transactions on Industrial Electronics • 2019
Irreversible electroporation (IRE) for disinfection applications involve exposing the specimen cell membrane to a pulsed electric field in order to kill harmful microorganisms. High-voltage (HV) pulses, of relatively short durations in range of few microseconds, are generated across the sample chamber. The HV pulse specifications such as voltage magnitude, waveform, repetition rate, and duration differ according to the conditions of the sample being processed. This paper proposes a new step-up power electronic converter topology for generating the required HV pulses from a relatively low input voltage. The converter consists of two main stages; the first stage is responsible for boosting the input voltage to the desired level using input-parallel/output-series connected dc/dc modules, while the second stage forms the required HV pulses with the proper magnitude, duration, and repetition rate using modular multilevel converter submodules. The proposed topology is able to produce the HV pulses with controlled voltage and current stresses across the employed semiconductor switches and diodes; hence, it can be implemented with the market-available semiconductor technology. Mathematical analysis of the proposed topology is developed, and MATLAB/Simulink simulation results explore operational conditions. Experimental results from a scaled-down prototype validate the functionality of the proposed system.
M. Rahimnejad, Gholamreza Bakeri, G. Najafpour et al.
Biofuel Research Journal • 2014
Microorganisms in microbial fuel cells (MFC) liberate electrons while the electron donors are consumed. In the anaerobic anode compartment, substrates such as carbohydrates are utilized and as a result bioelectricity is produced in the MFC. MFCs may be utilized as electricity generators in small devices such as biosensors. MFCs still face practical barriers such as low generated power and current density. Recently, a great deal of attention has been given to MFCs due to their ability to operate at mild conditions and using different biodegradable substrates as fuel. The MFC consists of anode and cathode compartments. Active microorganisms are actively catabolized to carbon sources, therefore generating bioelectricity. The produced electron is transmitted to the anode surface but the generated protons must pass through the proton exchange membrane (PEM) in order to reach the cathode compartment. PEM as a key factor affecting electricity generation in MFCs has been investigated here and its importance fully discussed.
A. Hitchcock, C. N. Hunter, D. Canniffe
Microbial Biotechnology • 2019
Cyanobacteria are prokaryotic phototrophs that, in addition to being excellent model organisms for studying photosynthesis, have tremendous potential for light‐driven synthetic biology and biotechnology. These versatile and resilient microorganisms harness the energy of sunlight to oxidise water, generating chemical energy (ATP) and reductant (NADPH) that can be used to drive sustainable synthesis of high‐value natural products in genetically modified strains. In this commentary article for the Synthetic Microbiology Caucus we discuss the great progress that has been made in engineering cyanobacterial hosts as microbial cell factories for solar‐powered biosynthesis. We focus on some of the main areas where the synthetic biology and metabolic engineering tools in cyanobacteria are not as advanced as those in more widely used heterotrophic chassis, and go on to highlight key improvements that we feel are required to unlock the full power of cyanobacteria for future green biotechnology.
D. Park, So-Hee An, Yeawan Lee et al.
Toxics • 2022
Particulate matter, including airborne pathogens, is of particular concern because it can cause the spread of diseases through aerosol transmission. In this study, a new concept is proposed: on-demand antiviral electrostatic precipitators (ESPs) with electrothermal-based antiviral surfaces. We applied electrothermal-based antiviral surfaces to air-purifying applications and demonstrated that the proposed method is effective with regard to collecting airborne virus particles on collection plates in a two-stage ESP. With alternating current power, MS2 bacteriophage and H1N1 viruses were completely deactivated after exposure to 50 °C for 30 min. This remarkable antiviral performance via electrothermal effects indicates that on-demand platforms for self-antiviral surfaces can perform sterilization immediately without generating secondary pollutants, thus effectively preventing the spread of infectious microorganisms in public places. We believe that the results of this study can provide useful guidelines for the design and realization of practical and wearable devices for antiviral air-purifying applications.
Cristiane Ferreira Alfenas, Mariane Floriano, L. Santos et al.
LA Referencia (Red Federada de Repositorios Institucionales de Publicaciones Científicas) • 2011
Searching for a therapy capable of acting on bacteria resistance to the conventional endodontic treatment, a the Photodynamic Therapy (PDT) has been shown to be very efficient. the It consists in an association of a photosensitizer plus a specific light source, such as low power laser, generating very shor t and reactive chemical species that, in high concentrations, are toxic, promoting the killing of the bacteria, fungi and viruses. Several authors show the benefits of the Photodynamic Therapy in the decontamination of the root canal. The aim of this work is to make a literary review of protocols used in photodynamic therapy for reduction of microorganisms within root canal system.
Hyun Min Lee, Hong Rae Kim, Eunbeen Jeon et al.
Microorganisms • 2020
Plastic waste worldwide is becoming a serious pollution problem for the planet. Various physical and chemical methods have been tested in attempts to remove plastic dumps. However, these have usually resulted in secondary pollution issues. Recently, the biodegradation of plastic by fungal and bacterial strains has been spotlighted as a promising solution to remove plastic wastes without generating secondary pollution. We have previously reported that a Pseudomonas aeruginosa strain isolated from the gut of a superworm is capable of biodegrading polystyrene (PS) and polyphenylene sulfide (PPS). Herein, we demonstrate the extraordinary biodegradative power of P. aeruginosa in efficiently depolymerizing four different types of plastics: PS, PPS, polyethylene (PE) and polypropylene (PP). We further compared biodegradation rates for these four plastic types and found that PE was biodegraded fastest, whereas the biodegradation of PP was the slowest. Moreover, the growth rates of P. aeruginosa were not always proportional to biodegradation rates, suggesting that the rate of bacterial growth could be influenced by the composition and properties of intermediate molecules produced during plastic biodegradation, and these may supply useful cellular precursors and energy. In conclusion, an initial screening system to select the most suitable bacterial strain to biodegrade certain types of plastic is particularly important and may be necessary to solve plastic waste problems both presently and in the future.
A. Nawaz, A. Hafeez, Syed Zaghum Abbas et al.
Green Chemistry Letters and Reviews • 2020
ABSTRACT The increase in the industrial revolution, urbanization, and deficit in crude oil resources urged scientists to look for sustainable and renewable energy resources. Microbial fuel cells (MFCs) are bio-electrochemical devices that convert the chemical energy of bio mass into electrical energy utilizing microorganisms as biocatalysts. MFC is an enthralling technology, and it has many important applications. There are different designs of MFC currently in use, each having their pros and cons; however, the stacked MFC is so far generating the highest power output. Different factors, discussed in this review, contribute toward the efficiency of the process. An ample amount of research has been done to convert the theoretical framework of MFC into a practical application; however, the later still remains a big challenge. A plethora of technical problems is in the way for MFC to be driven toward up-scaling and real-world applications. This review discusses electron transfer mechanisms in MFCs and important factors affecting the performance of MFC. Reactor design is a main limiting factor in MFC technology, and this review also focuses on recent improvements in reactor designs and modifications. Moreover, some main applications of MFC technology, limitations, recent advancements, and future prospects are discussed. GRAPHICAL ABSTRACT
M. De La Cruz –Noriega, S. Rojas-Flores, R. Nazario-Naveda et al.
Environmental Research, Engineering and Management • 2022
Potential use of organic waste and microalgae generates bioelectricity and thereby reduces harmful effects on the environment. These residues are used due to their high content of electron-generating microorganisms. However, so far, they have not been used simultaneously. Therefore, this research uses mango waste and microalgae Spirulina sp. in double-chamber microbial fuel cells to generate bioelectricity. The cells were made at a laboratory scale using zinc and copper electrodes, achieving a maximum current and voltage of 7.5948 ± 0.3109 mA and 0.84546 ± 0.314 V, with maximum electrical conductivity of the substrate being 157.712 ± 4.56 mS/cm and an optimum operating pH being 5.016 ± 0.086. The cells showed a low internal resistance of approximately 205.056 ± 25 Ω, and a maximum power density of 657.958 ± 21.114 mW/cm2 at a current density of 4.484 A/cm2. This research provides an excellent opportunity for mango farmers and exporting and importing companies because they can use their own waste to reduce their electricity costs when this prototype is brought to a large scale.
M. L. K. Khider, T. Brautaset, Marta Irla
World Journal of Microbiology and Biotechnology • 2021
Worldwide, the use of methane is limited to generating power, electricity, heating, and for production of chemicals. We believe this valuable gas can be employed more widely. Here we review the possibility of using methane as a feedstock for biotechnological processes based on the application of synthetic methanotrophs. Methane monooxygenase (MMO) enables aerobic methanotrophs to utilize methane as a sole carbon and energy source, in contrast to industrial microorganisms that grow on carbon sources, such as sugar cane, which directly compete with the food market. However, naturally occurring methanotrophs have proven to be difficult to manipulate genetically and their current industrial use is limited to generating animal feed biomass. Shifting the focus from genetic engineering of methanotrophs, towards introducing metabolic pathways for methane utilization in familiar industrial microorganisms, may lead to construction of efficient and economically feasible microbial cell factories. The applications of a technology for MMO production are not limited to methane-based industrial synthesis of fuels and value-added products, but are also of interest in bioremediation where mitigating anthropogenic pollution is an increasingly relevant issue. Published research on successful functional expression of MMO does not exist, but several attempts provide promising future perspectives and a few recent patents indicate that there is an ongoing research in this field. Combining the knowledge on genetics and metabolism of methanotrophy with tools for functional heterologous expression of MMO-encoding genes in non-methanotrophic bacterial species, is a key step for construction of synthetic methanotrophs that holds a great biotechnological potential.
An Li, Yanan Chu, Xumin Wang et al.
Biotechnology for Biofuels • 2013
BackgroundA solid-state anaerobic digestion method is used to produce biogas from various solid wastes in China but the efficiency of methane production requires constant improvement. The diversity and abundance of relevant microorganisms play important roles in methanogenesis of biomass. The next-generation high-throughput pyrosequencing platform (Roche/454 GS FLX Titanium) provides a powerful tool for the discovery of novel microbes within the biogas-generating microbial communities.ResultsTo improve the power of our metagenomic analysis, we first evaluated five different protocols for extracting total DNA from biogas-producing mesophilic solid-state fermentation materials and then chose two high-quality protocols for a full-scale analysis. The characterization of both sequencing reads and assembled contigs revealed that the most prevalent microbes of the fermentation materials are derived from Clostridiales (Firmicutes), which contribute to degrading both protein and cellulose. Other important bacterial species for decomposing fat and carbohydrate are Bacilli, Gammaproteobacteria, and Bacteroidetes (belonging to Firmicutes, Proteobacteria, and Bacteroidetes, respectively). The dominant bacterial species are from six genera: Clostridium, Aminobacterium, Psychrobacter, Anaerococcus, Syntrophomonas, and Bacteroides. Among them, abundant Psychrobacter species, which produce low temperature-adaptive lipases, and Anaerococcus species, which have weak fermentation capabilities, were identified for the first time in biogas fermentation. Archaea, represented by genera Methanosarcina, Methanosaeta and Methanoculleus of Euryarchaeota, constitute only a small fraction of the entire microbial community. The most abundant archaeal species include Methanosarcina barkeri fusaro, Methanoculleus marisnigri JR1, and Methanosaeta theromphila, and all are involved in both acetotrophic and hydrogenotrophic methanogenesis.ConclusionsThe identification of new bacterial genera and species involved in biogas production provides insights into novel designs of solid-state fermentation under mesophilic or low-temperature conditions.
Shangjie Ge-Zhang, Taoyang Cai, Mingbo Song
Frontiers in Plant Science • 2023
As the most suitable potential clean energy power generation technology, biophotovoltaics (BPV) not only inherits the advantages of traditional photovoltaics, such as safety, reliability and no noise, but also solves the disadvantages of high pollution and high energy consumption in the manufacturing process, providing new functions of self-repair and natural degradation. The basic idea of BPV is to collect light energy and generate electric energy by using photosynthetic autotrophs or their parts, and the core is how these biological materials can quickly and low-loss transfer electrons to the anode through mediators after absorbing light energy and generating electrons. In this mini-review, we summarized the biological materials widely used in BPV at present, mainly cyanobacteria, green algae, biological combinations (using multiple microorganisms in the same BPV system) and isolated products (purified thylakoids, chloroplasts, photosystem I, photosystem II), introduced how researchers overcome the shortcomings of low photocurrent output of BPV, pointed out the limitations that affected the development of BPV’ biological materials, and put forward reasonable assumptions accordingly.
Raúl Ortega Pérez, José Carlos Nieto García, Victor M. Gallegos-Cedillo et al.
Agronomy • 2023
The use of microorganisms capable of promoting the growth and development of crops is generating interest at a global level as a sustainable technique in modern agriculture, especially in intensive farming systems, where the excessive use of synthetic fertilizers has led to environmental problems. The objective of this research was to evaluate the biofertilizing power of formulations enriched with plant growth-promoting bacteria (PGPB) (Azotobacter spp. to fix N and strains of Bacillus spp. to solubilize P and K not bioavailable for plants) to improve the fertility, quality, and productivity of a tomato crop and their potential use as an alternative to conventional fertilizers. Thus, NPK levels in soils, leaves, and fruits were evaluated; various parameters of fruit quality were measured; and an exhaustive analysis of the production and economic yields of the harvest was carried out. The results showed that the periodic supply of biofertilizers based on PGPB increased the harvest yield (20–32%) and favored the development of larger fruit sizes, which are economically more valuable, and the incomes increased even more than production (32–52%). The biofertilizers also demonstrated a positive effect on the solubilization of P and K in the soil, and the levels of P in leaves were also promoted. The capacity to mobilize the nutrients from soil to fruits was clearly favored when PGPB were inoculated periodically, and a reduction of up to 20% in synthetic fertilizers was accomplished (16, 34, and 23% increases for N, P, and K, respectively, against the treatment without PGPB and no fertigation reduction). Finally, the use of PGPB did not show appreciable differences regarding fruit quality parameters.
Adriana Páez, Andrea Lache-Muñoz, S. Medina et al.
Tecnología y ciencias del agua • 2019
Microbial fuel cells (MFC) are an alternative for electric power production based on the oxidation of organic matter, for that reason waste waters are been considered as source of organic matter which can be transformed by microorganisms with the capacity of generating electric power. Therefore, the use of this technology, allows fulfilling two objectives, electricity production and pollutant reduction. In this work, a two-chamber MFC was assembled and operated in discontinuous mode to evaluate the parameters of electricity production and COD reduction in a synthetic waste water (with an invariant nutritional composition), using Escherichia coli and Pseudomonas aeruginosa strains. Carbon cloth and graphite were employed as electrodes, and methylene blue as a mediator. The initial pH values of the synthetic wastewater used as a substrate were variated in the tests. According to the operating conditions described above, a maximum average value of 464 mV was obtained for the voltage in open circuit and a potential density of 3.98 mW/m 2 , using Escherichia coli with a pH value of 6.5, a mediator, and with graphite as the material for electrodes. Additionally, a significant decrease in chemical oxygen demand (COD) was achieved with 11.53% for E. coli being the highest one. Lastly, microbial quantification was done, obtaining a lower growth time also for Escherichia coli .
H. Nganguia, D. Palaniappan
Journal of Fluid Mechanics • 2024
Abstract The classical paper by Lighthill (Commun. Pure Appl. Maths, vol. 109, 1952, p. 118) on the propulsion of ciliated microorganisms has become the reference against which many modern studies on swimming in low Reynolds number are compared. However, Lighthill's study was limited to propulsion in a uniform flow, whereas several biologically relevant microorganisms experience non-uniform flows. Here we propose a benchmark for ciliary propulsion in paraboloidal flows. We first consider the axisymmetric problem, with the microorganisms on the centreline of the background flow, and derive exact analytical solutions for the flow field. Our results reveal flow features, swimming characteristics and performance metrics markedly different from those generated in a uniform flow. In particular, the background paraboloidal flow introduces a Stokes quadrupole singularity at the leading-order flow field, generating vortices. Moreover, we determine the necessary conditions on the strength of the background flow for optimal power dissipation and swimming efficiency. We then consider the more general case of a microorganism off the centreline of the background flow. In this case, the squirmer experiences a paraboloidal, linear shear and uniform flows due to its position relative to the flow's centreline. Our findings show that while the linear shear flow does not affect the translational and rotational velocities of the squirmer, it does influence the velocity field and, therefore, the power dissipation.
Nurfarhana Nabila Mohd Noor, Ilwon Jeong, Seokjin Yoon et al.
Microorganisms • 2024
This study examined the utilization of spent coffee grounds with different aqueous extraction methods for the bioelectricity generation from coastal benthic sediment through a sediment microbial fuel cell (SMFC) system. Different methods for the aqueous extraction of SCGs were evaluated, including rinsing and drying of the SCG (SMFC-CRD), immersion, rinsing and drying (SMFC-CRID), drying alone (SMFC-CD), and untreated SCG (SMFC-C). The caffeine concentration in the SCG was significantly reduced using pretreatments, with SMFC-CRID achieving the lowest concentration of 0.021 ± 0.001 mg/g. SMFC-CRD contributed to the generation of the highest current density of 213.7 mA/m2 during closed-circuit operation and exhibited the highest power density of 96.9 mW/m2 in the polarization test, due to the suitable caffeine content of 0.275 ± 0.001 mg/g in the SCG. This study could provide a cost-effective method for reusing SCGs (i.e., 128 g) while generating bioelectricity as an alternative energy source. These results suggest that pretreatment with SCGs is essential for achieving optimal power density and reducing the caffeine concentration in the SMFC system.
Samantha J. Gleich, Jacob A. Cram, J. Weissman et al.
ISME Communications • 2021
Ecological network analyses are used to identify potential biotic interactions between microorganisms from species abundance data. These analyses are often carried out using time-series data; however, time-series networks have unique statistical challenges. Time-dependent species abundance data can lead to species co-occurrence patterns that are not a result of direct, biotic associations and may therefore result in inaccurate network predictions. Here, we describe a generalize additive model (GAM)-based data transformation that removes time-series signals from species abundance data prior to running network analyses. Validation of the transformation was carried out by generating mock, time-series datasets, with an underlying covariance structure, running network analyses on these datasets with and without our GAM transformation, and comparing the network outputs to the known covariance structure of the simulated data. The results revealed that seasonal abundance patterns substantially decreased the accuracy of the inferred networks. In addition, the GAM transformation increased the predictive power (F1 score) of inferred ecological networks on average and improved the ability of network inference methods to capture important features of network structure. This study underscores the importance of considering temporal features when carrying out network analyses and describes a simple, effective tool that can be used to improve results.
Xiaomeng Liu, T. Ueki, Hongyan Gao et al.
bioRxiv (Cold Spring Harbor Laboratory) • 2021
Sustainable strategies for energy production are required to reduce reliance on fossil fuels and to power electronics without generating toxic waste.1-7 Generating electricity from water evaporation through engineered materials is a promising approach,8,9 but power outputs have been low and the materials employed were not sustainably produced. Microorganisms can be mass produced with renewable feedstocks. Here, we demonstrate that it is possible to engineer microbial biofilms as a cohesive, flexible material for long-term continuous electricity production from evaporating water. The biofilm sheets were the functional component in devices that continuously produced power densities (∼1 μW/cm2) higher than that achieved with non-biological materials. Current production scaled directly with biofilm-sheet size and skin-patch devices harvested sufficient electricity from the moisture on skin to continuously power wearable devices. The results demonstrate that appropriately engineered biofilms can perform as robust functional materials without the need for further processing or maintaining cell viability. Biofilm-based hydroelectric current production was comparable to that achieved with similar sized biofilms catalyzing current production in microbial fuel cells,10,11 without the need for an organic feedstock or maintaining cell viability. The ubiquity of biofilms in nature suggests the possibility of additional sources of biomaterial for evaporation-based electricity generation and the possibility of harvesting electricity from diverse aqueous environments.
S. Sharma, Archana Sharma
Transactions of the Indian National Academy of Engineering • 2020
Dielectric barrier discharge (DBD) is a promising method of producing non-thermal plasma, which is widely used in variety of industrial and biological applications including disinfection/sterilization. Plasma sterilization offers a faster, less toxic and versatile alternative to conventional sterilization techniques. 45 kV, 50 kHz high voltage high-frequency power supply was designed for generating DBD plasma. Experimental studies were conducted using DBD plasma on growth control in algae, breakdown of complex phenols for chemical wastewater treatment and generation of UV, ozone and other reactive species using DBD plasma discharges in ambient air. A portable DBD plasma-based sterilization system is developed for fighting the Covid-19 pandemic. Quartz tube is used as a dielectric medium between copper foil—SS electrodes and 17 kV, 30 kHz pulse is applied across it, which produces intense DBD across SS mesh. This system can sterilize and disinfect the microorganism contaminated surfaces, garments and used disposable protective gears with UV, ozone and short-lived molecules of metastable states and excited chemical species of nitrogen and oxygen produced during the DBD plasma discharges in ambient air.
Han Chen, Yuanming Li, Zanyun Ying et al.
RSC Advances • 2023
Microbial fuel cells (MFCs) are widely acknowledged to be a promising eco-friendly abatement technology of pollutants, and are capable of generating electricity. However, the poor mass transfer and reaction rate in MFCs significantly decrease their treatment capacity for contaminants, especially hydrophobic substances. The present work developed a novel MFC integrated with an airlift (ALR) reactor using a polypyrrole modified anode to promote the bioaccessibility of gaseous o-xylene and attachment of microorganisms. The results indicated that the established ALR-MFC system showed excellent elimination capability, with removal efficiency exceeding 84% even at high o-xylene concentration (1600 mg m−3). The maximum output voltage of 0.549 V and power density of 13.16 mW m−2 obtained by the Monod-type model were approximately twice and sixfold higher than that of a conventional MFC, respectively. According to the microbial community analysis, the superior performances of the ALR-MFC in terms of o-xylene removal and power generation were mainly ascribed to the enrichment of degrader (i.e. Shinella) and electrochemical active bacteria (i.e. Proteiniphilum). Moreover, the electricity generation of the ALR-MFC did not decrease at a high O2 concentration, as O2 was conducive to o-xylene degradation and electron release. The supplication of an external carbon source such as sodium acetate (NaAc) was conducive to increasing output voltage and coulombic efficiency. The electrochemical analysis revealed that released electrons can be transmitted with the action of NADH dehydrogenase to OmcZ, OmcS, and OmcA outer membrane proteins via a direct or indirect pathway, and ended up transferring to the anode directly.
Á. E. Martínez de Alba, M. B. Rubio, M. E. Morán-Diez et al.
Microorganisms • 2021
This study examined the microbicidal activity of ultraviolet (UV)-C185–256-nm irradiance (robot 1) and ozone generated at UV-C185-nm by low-pressure mercury vapor lamps (robot 2) adapted to mobile robotic devices for surface decontamination, which was achieved in less than 1 h. Depending on their wall structure and outer envelopes, many microorganisms display different levels of resistance to decontaminating agents. Thus, the need for novel disinfection approaches is further exacerbated by the increased prevalence of multidrug-resistant bacteria, as well as the potential of novel microorganisms, with the ability to cause disease outbreaks. To set up a rapid and effective approach for microorganisms propagation prevention, we focused on the effects of UV-C and ozone on a distinct microorganism survival ratio. A set of microorganisms, including Escherichia coli, Micrococcus luteus, Saccharomyces cerevisiae, Trichoderma harzianum, and Bacillus subtilis, were used to evaluate the disinfection power of UV-C and UV-C plus ozone generating robots. UV-C disinfection can be suited to ad hoc tasks, is easy to operate, requires low maintenance, does not have the need for the storage of dangerous chemicals, and does not produce by-products that may affect human health and the environment. The robotic cumulative irradiation technology developed (fluence accumulated values of 2.28 and 3.62 mJ cm−2, for robot 1 and 2, respectively), together with the production of ozone (with a maximum peak of 0.43 ppm) capable of reaching UV-C shaded surfaces, and analyzed in the current study, despite being designed for the need to reduce the risk of epidemic outbreaks in real-life scenarios, represents a versatile tool that could be employed for air and surface disinfection within many circumstances that are faced daily.
Julia Maria Kurth, Marie-Caroline Müller, Cornelia Ulrike Welte et al.
Microorganisms • 2021
Methanogenic archaea operate an ancient, if not primordial, metabolic pathway that releases methane as an end-product. This last step is orchestrated by the methyl-coenzyme M reductase (MCR), which uses a nickel-containing F430-cofactor as the catalyst. MCR astounds the scientific world by its unique reaction chemistry, its numerous post-translational modifications, and its importance in biotechnology not only for production but also for capturing the greenhouse gas methane. In this report, we investigated MCR natively isolated from Methermicoccus shengliensis. This methanogen was isolated from a high-temperature oil reservoir and has recently been shown to convert lignin and coal derivatives into methane through a process called methoxydotrophic methanogenesis. A methoxydotrophic culture was obtained by growing M. shengliensis with 3,4,5-trimethoxybenzoate as the main carbon and energy source. Under these conditions, MCR represents more than 12% of the total protein content. The native MCR structure refined at a resolution of 1.6-Å precisely depicts the organization of a dimer of heterotrimers. Despite subtle surface remodeling and complete conservation of its active site with other homologues, MCR from the thermophile M. shengliensis contains the most limited number of post-translational modifications reported so far, questioning their physiological relevance in other relatives.
Regina S. Redman, Yong Ok Kim, Sang Cho et al.
Microorganisms • 2021
Studies were undertaken to determine if fungal endophytes from plants in stressful habitats could be commercialized to generate climate resilient crop plants. Fungal endophytes were isolated from weedy rice plants and grasses from South Korea and the USA, respectively. Endophytes (Curvularia brachyspora and Fusarium asiaticum) from weedy rice plants from high salt or drought stressed habitats in South Korea conferred salt and drought stress tolerance to weedy rice and commercial varieties reflective of the habitats from which they were isolated. Fungal endophytes isolated from grasses in arid habitats of the USA were identified as Trichoderma harzianum and conferred drought and heat stress tolerance to monocots and eudicots. Two T. harzianum isolates were exposed to UV mutagenesis to derive strains resistant to fungicides in seed treatment plant protection packages. Three strains that collectively had resistance to commonly used fungicides were used for field testing. The three-strain mixture (ThSM3a) increased crop yields proportionally to the level of stress plants experienced with average yields up to 52% under high and 3–5% in low stress conditions. This study demonstrates fungal endophytes can be developed as viable commercial tools for rapidly generating climate resilient crops to enhance agricultural sustainability.
Stina Hedžet, Maja Rupnik, Tomaž Accetto
Microorganisms • 2021
Intestinal phages are abundant and important components of gut microbiota, yet the isolated and characterized representatives that infect abundant gut bacteria are sparse. Here we describe the isolation of human intestinal phages infecting Bacteroidesuniformis. Bacteroides is one of the most common bacterial groups in the global human gut microbiota; however, to date not many Bacteroides specific phages are known. Phages isolated in this study belong to a novel viral genus, Bacuni, within the Siphoviridae family. Their genomes encode diversity-generating retroelements (DGR), which were shown in other bacteriophages to promote phage adaptation to rapidly changing environmental conditions and to broaden their host range. Three isolated phages showed 99.83% genome identity but one of them infected a distinct B. uniformis strain. The tropism of Bacuni phages appeared to be dependent on the interplay of DGR mediated sequence variations of gene encoding putative phage fimbrial tip proteins and mutations in host genes coding for outer-membrane proteins. We found prophages with up to 85% amino acid similarity over two-thirds of the Bacuni phage genome in the B. acidifaciens and Prevotella sp. genomes. Despite the abundance of Bacteroides within the human microbiome, we found Bacuni phages only in a limited subset of published gut metagenomes.
H. Keykha, A. Asadi
Advances in Civil Engineering Materials • 2017
This technical note aims to show the utility of solar energy coupled by electrobiogrouting as an environmentally friendly source of energy and prevent disposal of Ammonium in soil for the successful application of bacteria for soil improvement. A small-scale column electrokinetic cell was set up to inject carbonate-producing bacteria into the soil. Also, a solar power supply was utilized to generate a dc voltage of around 35 V for different treatment times. The results showed that the application of the concentrated solar-powered electro-microbiologically induced calcium carbonate precipitation (CSP-E-MICP) method to the soil increased the unconfined compressive strength of the soil at different curing time. The results of this experiment revealed that the unconfined shear strength of the soil increased due to the calcium carbonate (CaCO3) precipitation between the soil particles. In this method, the ammonium (NH4+) was retained in the cathode chamber by the graphite cathode electrode, and the pollution prevention system minimized the leakage of NH4+ ions into the soil.
H. T. Dinh, Hiromi Kambara, Yoshiki Harada et al.
Microbes and Environments • 2021
The present study investigated bioelectrical methane production from CO2 without organic substances. Even though microbial methane production has been reported at relatively high electric voltages, the amount of voltage required and the organisms contributing to the process currently remain unknown. Methane production using a biocathode was investigated in a microbial electrolysis cell coupled with an NH4+ oxidative reaction at an anode coated with platinum powder under a wide range of applied voltages and anaerobic conditions. A microbial community analysis revealed that methane production simultaneously occurred with biological denitrification at the biocathode. During denitrification, NO3– was produced by chemical NH4+ oxidation at the anode and was provided to the biocathode chamber. H2 was produced at the biocathode by the hydrogen-producing bacteria Petrimonas through the acceptance of electrons and protons. The H2 produced was biologically consumed by hydrogenotrophic methanogens of Methanobacterium and Methanobrevibacter with CO2 uptake and by hydrogenotrophic denitrifiers of Azonexus. This microbial community suggests that methane is indirectly produced without the use of electrons by methanogens. Furthermore, bioelectrical methane production occurred under experimental conditions even at a very low voltage of 0.05 V coupled with NH4+ oxidation, which was thermodynamically feasible.
R. Peña-Eguiluz, J. A. Pérez-Martínez, J. Solís-Pacheco et al.
The European Physical Journal Applied Physics • 2010
Microplasmas are nowadays a powerful tool with multiple practical applications. The performance of a specific instrumentation for a plasma needle capable of producing non-thermal plasmas and a DBD reactor able to produce atmospheric pressure plasmas, both of them designed and already constructed, is reported. These devices operate at 13.56 MHz and are driven by a specifically built radio frequency (RF) resonant converter. The reactors, which operate at atmospheric pressure in a He-air gas mixture at a 1.5 SLPM flow, have been successfully applied to eliminate E. coli bacteria. In the needle case, bacterial samples were submitted typically to a 500 V peak voltage plasma discharge for 120 s. In the DBD treatment, the samples were processed with typical 750 V peak voltage plasma discharges for 80 s. The sample pH was used as a criterion to measure the effectiveness of the plasma treatment, in such a way that the return to the basal pH value after the treatment can be assumed as the validation of the complete bacterial elimination.
S. Gowshmeed, R. Vithiya, E. Ramassamy
2023 International Conference on System, Computation, Automation and Networking (ICSCAN) • 2023
Pulsed electric fields (PEF), a non-thermal food preservation technique, employs short electrical pulses that disable bacteria while having a negligible impact on the properties of the food. PEF technology aims to deliver nutritious meals to customers. PEF technology is regarded to be superior to traditional thermal processing methods for food quality attributes because it prevents or significantly reduces negative variations to the sensory and physical features of food. Foods that are placed between two electrodes using PEF technology are treated using high voltage pulses. Most PEF research has been centred on how PEF treatments affect the microbial inactivation of milk, dairy goods, egg-related goods, juice along with and other liquid meals. Successful applications of the PEF treatment include the inactivation of microorganisms, enhancement of pressurising productivity, and extraction of juice from food-producing plants, as well as intensifying food dehydrating and drying. The creation of a kind of solid, semisolid, and liquid food preservation system based on PEF. The creation of the chamber and the accomplishment of its tomato ketchup test A 20 kHz frequency was used to test the system.
G. Bucciarelli, Maren Lechner, Audrey Fontes et al.
Toxins • 2021
Tetrodotoxin (TTX) is a potent neurotoxin that was first identified in pufferfish but has since been isolated from an array of taxa that host TTX-producing bacteria. However, determining its origin, ecosystem roles, and biomedical applications has challenged researchers for decades. Recognized as a poison and for its lethal effects on humans when ingested, TTX is primarily a powerful sodium channel inhibitor that targets voltage-gated sodium channels, including six of the nine mammalian isoforms. Although lethal doses for humans range from 1.5–2.0 mg TTX (blood level 9 ng/mL), when it is administered at levels far below LD50, TTX exhibits therapeutic properties, especially to treat cancer-related pain, neuropathic pain, and visceral pain. Furthermore, TTX can potentially treat a variety of medical ailments, including heroin and cocaine withdrawal symptoms, spinal cord injuries, brain trauma, and some kinds of tumors. Here, we (i) describe the perplexing evolution and ecology of tetrodotoxin, (ii) review its mechanisms and modes of action, and (iii) offer an overview of the numerous ways it may be applied as a therapeutic. There is much to be explored in these three areas, and we offer ideas for future research that combine evolutionary biology with therapeutics. The TTX system holds great promise as a therapeutic and understanding the origin and chemical ecology of TTX as a poison will only improve its general benefit to humanity.