Discover insights from thousands of peer-reviewed papers on microbial electrochemical systems
Xin Wu, Wujing Cao, Hongliu Yu et al.
IEEE/ASME Transactions on Mechatronics · 2022
The capability to generate electricity from human motion can reduce the battery requirements for wearable devices. The key challenge faced by wearable energy harvesters is the generation of sufficient power without interfering with the wearer. To our knowledge, currently available joint-motion energy harvesters are all for level walking (LW). In this study, we developed an energy-harvesting exoskeleton that can generate electricity during LW, downhill walking (DW), and stair descent (SD) without sensors. Bi-directional knee motion is transformed to the unidirectional rotation of the generator by one-way bearing and appropriate gear train. The average electricity generated by each leg for the three modes of walking is $5.4 \pm 0.8{\rm{\ W\ }}({\text{LW},\ 5{\rm{\ km}}/\mathrm{h}})$ , $6.5 \pm 0.6{\rm{W\ }}({\text{DW},\ 5{\rm{\ km}}/\mathrm{h}})$ , and $8.2 \pm 0.4{\rm{W\ }}({\text{SD},4{\rm{\ stairs}}/\mathrm{s}})$ , respectively. The Pearson coefficients of the knee angle under exo- on and no-exo conditions are 0.995 (LW), 0.996 (DW), and 0.999 (SD), respectively. The cost of harvesting is −0.006 (LW) and −0.01 (DW). The increase in the metabolic rate in energy harvesting on condition is merely 2.3% (LW) and 1.6% (DW) compared to the no-exo condition. There is no significant increase in the metabolic cost while generating electricity $(P\ = \ 0.363,$ LW; $P\ = \ 0.662,$ DW). In summary, the knee energy-harvesting exoskeleton developed in this study can generate substantial and sustainable electricity with little extra effort, which indicates its potential as a means to charge-powered portable exoskeletons and prosthetics.
Kazuya Watanabe
Encyclopedia of Industrial Biotechnology · 2010
Biofuel cells are devices for generating electricity from chemical fuels (such as hydrogen and organic compounds) using biological catalysts (i.e. enzymes and/or living microbes) for electrode reactions. They could be divided into two categories based on types of catalysts; namely, enzyme fuel cells (EFCs), and microbial fuel cells (MFCs). In this article, procedures for evaluating biofuel cells are described, since appropriate evaluation is fundamental to developing efficient processes and also for comparing biofuel cells developed in different laboratories. Special focus is on the evaluation of MFCs, since MFCs need more diverse criteria than EFCs for performance evaluation; however, EFC evaluation is also possible using the procedures and parameters described in the article. Keywords: biofuel cell; microbial fuel cell; enzyme fuel cell; bioenergy; sustainable process
I. Ieropoulos, P. Ledezma, Giacomo Scandroglio et al.
Oxford Scholarship Online · 2018
Energy resulting from metabolism is essential for any living system—from single-cell to multicellular organisms. This also applies to symbiotic robots (SymBots), which function utilizing the energy (electricity) generated by living microorganisms. In the context of living technologies, artificial symbiosis between the living and the artificial entities of the machine becomes vital for the whole system. If the living entity stops generating energy, the mechatronic system ceases to work yet it is the mechatronic system that provides the microbes with food, and gets rid of their waste. This chapter presents and discusses SymBots, based on EcoBots that operate using Microbial Fuel Cells as onboard living energy devices. The interface between science and engineering is exemplified through the study and optimization of MFCs, producing the necessary data for technological implementation. Biological inspiration stems from living organisms metabolizing and adapting to the environment (homeostasis), which is the main process transferred to engineering.
Nasim Mia, Md. Mohinul Islam, Sumon Bonik et al.
2024 3rd International Conference on Advancement in Electrical and Electronic Engineering (ICAEEE) · 2024
Microbial fuel cells (MFC) as a substitute for generating electricity and managing waste has gained popularity. MFCs are viewed as a potential alternative for conventional power sources because they harness the power of microbes to convert the chemical energy in organic matter into electricity. This study focused on performance of a terrestrial microbial fuel cell (TMFC) that utilized easily obtainable ingredients from local markets and sewage sludge. The designed system has an anode, cathode, cathodic chamber, proton exchange system, and electrode catalyst. The process starts with assembling the unit and collecting wastes for preparing the substrate. After that, the respective solution is prepared for the anode and cathode chambers. Finally, electrodes are connected, and the voltage is measured after a specific time. Modifying the catalyst recorded the maximum voltage as 1168 mV, and the highest power generation amount was calculated as 143.1 mW/m2. Microbial electricity generation using MFCs could emerge as an effective form of bioenergy in the coming years, during which abundant organic waste can be reduced and valorized.
Alfredo Marvão Pereira, Rui Marvão Pereira
Archives of Business Research · 2021
This paper addresses the issue of financing the excess costs of electricity generation from currently installed renewable energy production capacity. We use a dynamic computable general equilibrium model of the Portuguese economy. We consider three issues: the effects of the excess-costs; the effects of annuitizing the costs; and, the effects of different financing mechanisms. Following the logic of the tariff deficit, we recommend the annuitizing of these excess costs. This strategy is justified on distributional grounds. We also find that financing through carbon taxation is a better alternative than passing these excess costs to electricity consumers in the form of higher future prices. This is consistent with the idea that renewable production is not an issue pertaining to the electricity market but rather a part of the national quest for decarbonization. Finally, we show that there is little reason to extend such preferential financing to future renewable capacity installation.
Bilal Abdullah Nasir
Journal of Energy Research and Reviews · 2021
The construction of small-hydro power stations does not require high technologies, but needs to provide a river or stream water is smooth. Through the establishment of small dams on the stream can control the amount of water necessary to rotate the water turbine, which in turn converts the potential energy of water into kinetic energy. Through the transfer of kinetic energy of rotation of the turbine to the generator can convert this energy into electrical energy. The idea of our plan of research for electrical energy from the power of water using small- hydroelectric plants, which can be built on small rivers, streams, and through the construction of small dams to control the amount of water. Electrical energy derived from small- hydroelectric plants could help feed the electrical loads to areas isolated from the national grid and can be linked with the national grid to add additional electric power.
Sebastian Klaudiusz Tomczak
Energies · 2019
Companies operating in the energy sector are under pressure to boost the level of green energy production. The use of renewable energy sources will have a positive impact on the environment, but the basic question is whether power plants that produce electricity using renewable energy sources are in better financial condition than those that use only traditional energy sources. We address the latter using a new hybrid approach that extends prior research by combining three analyses: ratio analysis with a large set of indicators, the Altman model and cluster analysis. To test the statistical significance of differences between groups, Student’s t-test is applied. The sample concerns companies from the Baltic States and Central Europe in the years 2008–2017. The results indicate that in most cases there is no statistical difference in the financial standing of companies that use renewable energy sources and those that generate only fossil fuel-based energy.
M. J. Goodwin
Journal of Synthetic Lubrication · 1985
Abstract This paper describes the lubrication and cooling systems of modern electricity generating plant, particularly those of the generator. The paper discusses the development of the power plant manufacturing industry and shows how critical the selection of lubricants and coolants is on the efficiency of the plant. The operation and layout of plant of up to 1,200 MW power rating are described and the various lubrication and cooling systems which are incorporated are identified. The cooling media discussed include non‐synthetic, semi‐synthetic, and synthetic fluids, and in each case the reasons for its selection are examined. Basic design calculations relating to lubrication and cooling systems are included. The paper concludes by examining trends in plant design and how they may affect future selection of lubricants and coolants.
E. J. Workman, R. E. Holzer
Review of Scientific Instruments · 1939
A generating voltmeter type automatic electric field recorder designed for continuous measurement of surface electric fields in thunderstorms is described. The performance of the instrument in the field under thunderstorm conditions is discussed. The application of this instrument to the study of the normal potential gradient of the earth is suggested.
Paul L Joskow
American Economic Review · 2011
Economic evaluations of alternative electric generating technologies typically rely on comparisons between their expected “levelized cost” per MWh supplied. I demonstrate that this metric is inappropriate for comparing intermittent generating technologies like wind and solar with dispatchable generating technologies like nuclear, gas combined cycle, and coal. It overvalues intermittent generating technologies compared to dispatchable base load generating technologies. It also likely overvalues wind generating technologies compared to solar generating technologies. Integrating differences in production profiles, the associated variations in wholesale market prices of electricity, and life-cycle costs associated with different generating technologies is necessary to provide meaningful comparisons between them.
Lucas Richter, Tom Bender, Steve Lenk et al.
Energies · 2024
Thanks to various European directives, individuals are empowered to share and trade electricity within Renewable Energy Communities, enhancing the operational efficiency of local energy systems. The digital transformation of the energy market enables the integration of decentralized energy resources using cloud computing, the Internet of Things, and artificial intelligence. In order to assess the feasibility of new business models based on data-driven solutions, various electricity consumption time series are necessary at this level of aggregation. Since these are currently not yet available in sufficient quality and quantity, and due to data privacy reasons, synthetic time series are essential in the strategic planning of smart grid energy systems. By enabling the simulation of diverse scenarios, they facilitate the integration of new technologies and the development of effective demand response strategies. Moreover, they provide valuable data for assessing novel load forecasting methodologies that are essential to manage energy efficiently and to ensure grid stability. Therefore, this research proposes a methodology to synthesize electricity consumption time series by applying the Box–Jenkins method, an intelligent sampling technique for data augmentation and a probabilistic forecast model. This novel approach emulates the stochastic nature of electricity consumption time series and synthesizes realistic ones of Renewable Energy Communities concerning seasonal as well as short-term variations and stochasticity. Comparing autocorrelations, distributions of values, and principle components of daily sequences between real and synthetic time series, the results exhibit nearly identical characteristics to the original data and, thus, are usable in designing and studying efficient smart grid systems.
I. P. Kravets, O. I. Bashynskiy, A. P. Kushnir et al.
Fire Safety · 2019
The article deals with the problems of fire hazard of electricity-generating equipment during their exploitation. Intensive electrification of industrial and residual objects leads to the saturation of these objects with different electricity-generating equipment. Functioning of such equipment is accompanied with high heat emission and contains significant fire hazard. The electric current in an electrical conductor produces heat, when electric energy turns into thermal. All electrical equipment must be produced in strict adherence to fire safety rules and requirements. Ignoring these requirements causes heating of conductors through all the length, spunking of isolation, sparkling and, as a result, breaking-out of fire. Therefore, reducing the probability of fire even in the cases of abnormal work, wrong exploitation and foreseen refuses is the main task during planning and exploitation of electrical equipment and also during selection of structural materials. The primary purpose of fire prevention measures in the electrical equipment is avoiding of its self-ignition, and localization of fire after the self-ignition of electricity-generating equipment. Fire safety during exploitation of electricity-generating equipment depends on its technical state. Correct choice of conductor cross section is very important. Protection stage of electrical equipment, type of wiring, and cable laying method must comply with environmental conditions and have the proper climatic implementation and placement category. Proper protective devices from a short circuit and overloads must be used. Their operating values must be also foreseen. All above-mentioned measures prevent fires and explosions during exploitation of electrical equipment. Key
M. Sorgenfrei, G. Tsatsaronis
Volume 6: Energy, Parts A and B · 2012
Carbon capture from advanced Integrated Gasification Combined-Cycle (IGCC) processes should outperform conventional coal combustion with subsequent CO2 separation in terms of efficiency and CO2 capture rates. This paper provides a thermodynamic assessment, using exergy analysis, of a novel Syngas Redox (SGR) process for generating electricity. The power island of the proposed process uses syngas produced by coal gasification and then cleaned through high-temperature gas desulfurization (HGD). Hematite (Fe2O3) is used as an oxygen carrier to oxidize the syngas. To achieve a closed-cycle operation, the reduced iron particles are first partially re-oxidized with steam and then fully re-oxidized with pressurized air. One advantage of this design is that the resulting hydrogen (using steam in the re-oxidation section) can be utilized within the same plant or be on sold as a secondary product. In the proposed process, diluted hydrogen is combusted in a gas turbine. Heat integration is central to the design. The different requirements of syngas cooling, particle-regeneration, and coal drying necessitated the use of a heat-recovery steam generator (HRSG) supplying steam at three pressure levels. To establish a benchmark, the rate of exergy destruction within the SGR process was compared to a coal-fed Shell gasification IGCC design with Selexol-based pre-combustion capture. Process simulation was undertaken using Aspen Plus and EES (Engineering Equation Solver).
T.R. Shaw
Anti-Corrosion Methods and Materials · 1965
The Central Electricity Generating Board is responsible for the operation and maintenance of 233 Generating Stations, 602 Transmission Sub‐Stations, 7,780 miles of Overhead and 602 miles of Underground Transmission Lines. The current building and reinforcement programme is involving considerable financial and technical investment. To support this investment, part of the Board's policy is to promote the issue of Standards and Specifications with the object of controlling quality and the consequent reduction of maintenance down times. The contribution to this policy by incorporating anti‐corrosion techniques in Steel Structures Standards and Specifications can be considerable. Ultimately, of course, maintenance becomes a necessity and for this purpose the Standards and Specifications produced extend themselves to the materials used, principally paint, with the object of reducing maintenance periods to a minimum.
Allen Lemuel G. Lemence, Jordi Cravioto, Benjamin C. McLellan
Energies · 2024
In the quest for sustainable development, the energy sector must address the three pillars of sustainability: economic, environmental, and social. However, compared to the other pillars, research on social sustainability has been relatively limited. A systematic literature review was conducted covering 143 peer-reviewed articles (after initial screening) to explore the current state and opportunities in the social sustainability assessment of electricity generating systems. The contributions of this research are two-fold: first is the analysis of the elements of social sustainability assessment, particularly the explicit and implicit definitions of social sustainability as well as the roles and nature of involvement of stakeholders. Second is the analysis of the intersections among framework elements. The insights provided serve as a valuable resource in conducting social sustainability assessments of electricity generating systems as well as inform researchers and stakeholders concerning future research directions.
An Liang Hu
Applied Mechanics and Materials · 2014
In this paper, the internal structure and category of fuel cell were firstly described as well as the electricity-generating system. In addition, the current situation of the application of fuel cell in the electricity-generating industry was discussed including its prospects. In the end, the assumption of the application of fuel cell in the electricity-generating industry was explored.
R.W. PRIOR
Aslib Proceedings · 1967
Before discussing in detail the range of information bulletins issued by CEGB Information Services, I should like to give a few details of the structure of the British electricity supply industry.
Sagita Rochman
Tibuana · 2020
At present the use of wind energy in Indonesia is still relatively low, but has enormous potential. One reason is because the average wind speed in the territory of Indonesia is classified as low wind speed, which ranges from 3 m / s to 5 m / s making it difficult to produce electrical energy on a large scale. However, the wind potential in Indonesia is available almost all year long, making it possible to develop small-scale power generation systems. Innovations in modifying windmills need to be developed so that in conditions of low wind speeds can produce electrical energy.
 In this research, a prototype was developed by designing a vertical axis windmill power plant model Savonius using a permanent magnet generator, which can produce optimal electrical energy by utilizing relatively low wind speeds.From the generator test it was found that with a rotor rotation of 50 rpm up to 500 rpm can produce an electrical voltage of 0.02V to 10V and an electric current of 0.60A to 4.53A.
Tian Jiao Meng
Advanced Materials Research · 2014
By recycling the kinetic energy in gyms, a generating system is closely related to this design, in which a perfect output circuit has been used so as to output a constant voltage no matter how variable the power of the kinetic energy is. Consequently, a continuing and constant current will be output when an electrical storage device is equipped. Based on a systematic analysis of the generator, accumulator and loading equipment, this thesis would grasp the variation tendency of each variable in the generating system, thus to realize the grid-connected operation of the existing alternating current and the generating system built-up by the fitness equipment.
P.R. Mullins
Aslib Proceedings · 1975
In a paper of this nature it is difficult to avoid presenting a catalogue in the what we do in our …' vein. Yet any claim to usefulness will probably lie in providing an outline of the service for comparison purposes and, incidentally, in showing possible areas of co‐operation with other information units. For that reason, before describing the information activities of the Central Electricity Generating Board (CEGB), it may be appropriate to outline the structure of the British electricity supply industry, bringing out the position in it of the CEGB, and then to consider the organization of the Generating Board itself.
Brett Geissler, Alicia M. Jones, Vic Keasler
CORROSION 2016 · 2016
Abstract Hydrogen sulfide generation is one of the key detriments linked to microbial activity in the oil and gas industry and is the most likely cause of most microbiologically influenced corrosion. H2S is extremely corrosive to most metals and can significantly devalue produced fluids and gases as well as raise HS&E concerns for production facilities. Microbial sulfidogenesis has historically been linked to only a few types of sulfate reducing bacteria that are capable of growth in Modified Postgate’s B medium, but recent advances in microbial identification techniques have shown that the sulfide generating population in the industry is made up of over 190 different genera. Metabolic studies have shown that the vast majority of these microbes require thiosulfate, elemental sulfur, (bi) sulfite, and other sulfur compounds for energy production, and can therefore not be cultured using standard oilfield methods. This paper discusses the prevalence and distribution of the varied population of sulfide generating bacteria and archaea that have been identified by DNA sequencing from over 7000 samples obtained from numerous sites throughout hydrocarbon production facilities found all over the world.
Paul L Joskow*
The New Energy Paradigm · 2007
Abstract Policy-makers in many countries are expressing concerns that competitive wholesale electricity markets are not providing appropriate incentives to stimulate ‘adequate’ investment in new generating capacity at the right time, in the right places, and using the right technologies. These concerns are often expressed in the context of concerns about ‘supply security’, ‘reliability’, ‘resource adequacy’, or ‘supply diversity’. In most cases the concerns have been raised as policy-makers observe growing electricity demand, shrinking reserve margins, and rising prices, but little evidence of investment in new generating capacity responding to balance supply and demand consistent with traditional metrics for generation resource ‘adequacy’.
Isabel Hess, Stephen Chamot, Blake Boren et al.
Preprints.org · 2024
This study identifies hydraulically amplified self-healing electrostatic (HASEL) transducers as electricity generators by assessing their capability to convert mechanical energy into electrical energy, contrary to their conventional role as actuators. HASELs are soft, variable-capacitance transducers inspired by biological muscles, which were developed to mimic the flexibility and functionality of natural muscle tissues. This research characterizes HASELs as generators by reversing their energy conversion mechanism—applying mechanical energy to deform the HASEL to generate electrical energy. The study includes analytic modeling and empirical evaluation, thereby assessing the practical laboratory performance of HASELs as electricity generators. Outcomes of the study include the following: (i) up to 2.5 mJ per cycle per HASEL pouch of positive net energy generation in experimental testing—corresponding to an energy density of 2.0 mJ cm−3; (ii) a maximum theoretical conversion of 5.2 mJ cm−3; (iii) the electromechanical characteristics governing efficient conversion; and (iv) future design optimization strategies to enhance the effectiveness of HASELs as electricity generators—potentially broadening their applicability and utility in research fields such as renewable energy and general adaptive electricity generation.
I. R. Brookes
CORROSION 1978 · 1978
From the beginning of Britain's nuclear power programme it has always been the Central Electricity Generating Board's (CEGB) policy as operators of nuclear power plant, to maintain sufficient staff and facilities to enable us to test experimentally and examine theoretically, certain proposals or features of design in any reactor tendered to us. The procedure whereby the CEGB submits to the reactor construction company a technical specification which is transformed into a design by the company ensures a large measure of cooperation between the two organisations before and after a design is issued. Although this ensures that principles are agreed beforehand, the CEGB may question or test certain of the proposals put forward by the construction company. In this way the CEGB becomes what it terms an 'informed buyer'.
Ndala Yves Mulongo, Cliton Aigbavboa
Preprints.org · 2018
In response to ever-increasing concerns regarding ecological degradation and societal impact, numerous stakeholders such as non-governmental organisations, government officials, end-users, the mass media, and community activists have compelled business organizations, particularly multi-national companies to lessen harmful greenhouse gases emissions associated with their production activities. Energy sector is one of the biggest harmful greenhouse gases emission producer, hence, decision-makers within the energy sector are forced to promote and build environmental friendly and sustainable power generation plants. To this end, the concept of sustainability in the electricity sector has attracted so much attention from academics and industrial practitioners over the last three decades. Albeit, an important number of sustainability assessment frameworks for electricity generating technologies are found in the current literatures, three major drawbacks have emerged from those frameworks. Firstly, there is a lack of a holistic and comprehensive sustainability assessment framework for different power generation plants. Secondly, from economic aspect, the most used model (Levelised Cost of Electricity) to measure the cost performance of various electricity generating technologies is biased and is not inclusive enough, because, it only considers the capital, Operations and Maintenance, and fuel costs. Hence, snubbing crucial elements to business decision. Lastly, in the current literature, there is no a single sustainability assessment model that considers all the phases of electrical energy’s lifecycle. Considering these flaws, the novelty of this study is the development of a new, holistic theoretical sustainability assessment framework for power generation plants. The developed theoretical model includes 19 impact categories, 52 potential indictors, and 10 end points environmental, economic, and social aspects.
, Duangkamon Amonsaksopon
· 2002
Combinations of the beta-lactam and beta-lactamase inhibitor are antibiotics extensively used in clinic for the treatment of infectious disease caused by the beta-lactamase producing bacteria. The mode of action of beta-lactamase inhibitor is regarded as irreversible, suicide inhibitors of the target enzyme resulting in persistent activity of beta-lactams to inhibit bacterial cell wall synthesis, which leads to cell death. The present study aimed to evaluate the synergistic interaction between beta-lactams and beta-lactamase inhibitors on clinically important beta-lactamase producing gram-negative bacteria by checkerboard technique and time kill method. Clavulanic acid at 2 microgram/ml demonstrated synergy to amoxicillin against Moraxella catarrhalis and Haemophilus influenzae by reduction MIC of amoxicillin to 64 times. Similarly tazobactam at 4 .microgram/ml reduce the MIC of piperacillin against Klebsiella pneumoniae and Pseudomonas aeruginosa to 64 and 4 times, respectively. The MIC of cefoperazone against P. aeruginosa was decreased 8 times when being combined with sulbactam 8 microgram/ml whereas Acinetobacter baumannii required sulbactam 32 microgram/ml to reduce the MIC of cefoperazone. Additionally, beta-lactams (amoxicillin, piperacillin, cefoperazone) at 2 MIC in concomitant with beta-lactamase inhibitors at average concentration (clavulanic acid at 2 microgram/ml, tazobactam at 4 microgram/ml, sulbactam at 8 mg/ml) demonstrated the antibacterial properties and synergistic activity by decreasing colony forming unit more than 100 fold comparing with the most active single drug except for A. baumannii that required sulbactam at least 32 microgram/ml to show those properties. Regarding to post beta-lactamase inhibitor effect (PLIE), amoxicillin-clavulanic acid and piperacillin-tazobactam manifested the time period of PLIE that correlated to concentration of beta-lactamase inhibitors against H. influenzae and P. aeruginosa, respectively. Furthermore it found that one of three beta-lactamase inhibitors, clavulanic acid, demonstrated beta-lactamase induction effect by inducing Enterobacter cloacae to produce beta-lactamase that destroyed cefuroxime as tested by double disks as well as agar dilution methods. The MIC of cefuroxime was increased from 6 mg/ml to 32 microgram/ml on exposure to clavulanic acid 10 microgram/ml. The results obtained suggest that the concentration of beta-lactamase inhibitors and beta-lactams under studies are appropriate for clinical application.
Jenifar Das, Ashish Kumar Singh
bioRxiv (Cold Spring Harbor Laboratory) · 2024
Abstract Due to the adverse effects of synthetic colours on human health and the environment, there is a rapid shift towards the use of colours from natural sources like plants and microorganisms. Many pigment-producing microorganisms are identified and isolated from extreme environments like glaciers, ice cores, marine surface waters, etc. In this study, we have isolated 4 distinct pigment-producing bacterial strains from an Arctic stone sample collected from the vicinity of the Indian Research Station Himadri (78°55 ′ N 11°56 ′ E ), located at the International Arctic Research Base, NyÅlesund, Svalbard, Norway. Pigment production was optimised by identifying the right growth medium, temperature, pH, and incubation period. The morphological, cultural, and biochemical characteristics were identified using several experiments like Gram Staining, Catalase Test, Oxydative-Fermentative Test, etc. The objective of this study is to identify novel bacterial strains capable of producing distinct pigments for pharmaceutical and industrial applications.
Mehwish Saleem, Zunaira Azam, Saneela Kausar et al.
Pakistan BioMedical Journal · 2022
The term antimicrobial resistance refers to the ability to resist the effects of drugs formally used to treat them and this term relates only to bacteria becoming resistant. Microorganisms which are resistant to multiple drugs are known as multidrug resistant bacteria. Methods: Most of the experimental work to study the application of E-Test for detection of lactamase producing bacteria was carried out at Pathology Laboratory of Sir Ganga Ram Hospital Lahore. While the remaining research work was done in Microbiology Laboratory of Govt. Post Graduate Islamia College Cooper Road Lahore during the study period from December 2019 to March 2020. Total 60 samples of different patients were collected from Sir Ganga Ram Hospital Lahore and most of the samples were urine (n=25), followed by Blood (n=14), Pus (n=14), and sputum (n=7). Oxidase, indole, citrate utilization, sugar fermentation (Kligler iron agar medium) and urease tests were performed for the identification bacterial strains. Results: In all of 60 samples frequency of occurrence of E. coli, Enterobacter and Klebsiella strains were 59%, 23%, 18% respectively. Most of them (n=36) were ESBLs positive and about (n=24) were ESBLs negative and their percentage were 60% and 40% respectively. Extended spectrum β-lactamase (ESBL) producing strains of Enterobacteriaceae have now become as a significant issue in hospitalized and community patients. These microorganisms are liable for many diseases, for example, urinary tract infection, septicemia, hospitalized-acquired pneumonia, intra-abdominal abscess, brain abscess and device related infections. Conclusions: The frequency of ESBL producing bacteria in most hospitals is very high especially in the hospitals where broad spectrum antibiotics are generally recommended. Among gram negative bacteria, the emergence of resistance to expanded spectrum cephalosporins has been a major concern. Many of ESBL producing bacteria showed multidrug resistance.
Yong Yang, Olga Babich, Stanislav Sukhikh et al.
Foods and Raw Materials · 2020
Introduction. Increased resistance of microorganisms to traditional antibiotics has created a practical need for isolating and synthesizing new antibiotics. We aimed to study the antibiotic activity and resistance of bacteriocins produced by lactic acid bacteria and other microorganisms.
 Study objects and methods. We studied the isolates of the following microorganism strains: Bacillus subtilis, Penicillium glabrum, Penicillium lagena, Pseudomonas koreenis, Penicillium ochrochloron, Leuconostoc lactis, Lactobacillus plantarum, Leuconostoc mesenteroides, Pediococcus acidilactici, Leuconostoc mesenteroides, Pediococcus pentosaceus, Lactobacillus casei, Lactobacillus fermentum, Bacteroides hypermegas, Bacteroides ruminicola, Pediococcus damnosus, Bacteroides paurosaccharolyticus, Halobacillus profundi, Geobacillus stearothermophilus, and Bacillus caldotenax. Pathogenic test strains included Escherichia coli, Salmonella enterica, Staphylococcus aureus, Pseudomonas aeruginosa, Bacillus mycoides, Alcaligenes faecalis, and Proteus vulgaris. The titer of microorganisms was determined by optical density measurements at 595 nm. 
 Results and discussion. We found that eleven microorganisms out of twenty showed high antimicrobial activity against all test strains of pathogenic and opportunistic microorganisms. All the Bacteroides strains exhibited little antimicrobial activity against Gramnegative test strains, while Halobacillus profundi had an inhibitory effect on Gram-positive species only. The Penicillium strains also displayed a slight antimicrobial effect on pathogenic test strains.
 Conclusion. The antibiotic resistance of the studied lactic acid bacteria and other bacteriocin-producing microorganisms allows for their use in the production of pharmaceutical antibiotic drugs.
M Saiful Islam, Naima Moazzem, M Abdullah Yusuf et al.
Journal of Current and Advance Medical Research · 2014
Emergence of bacterial resistance causes limitation of the action of antimicrobial agents. Frequency of extended spectrum ?-Lactamase (ESBL) production is high among Escherichia coli (E. coli) and Klebsiella species. This has created a worldwide problem resulting in treatment failure. ESBLs have become widespread throughout the world. Microbes undergo mutation of genes, which can spread from cell to cell by mobile genetic elements such as plasmids, transposons and bacteriophages. Resistant bacteria flourish in areas of heavy antibiotic use such as hospitals and ICU. With widespread use of antibiotic, the frequency of penicillinase producing staphylococci increased. The availability of the second-generation cephalosporin, such as cefamondole, cefoxitin, and cefuroxime, or 3rd generation cephalosporin, such as cefotaxime, ceftazidime, ceftriaxone has been the leading cause of potential resistances in nosocomial Gram-negative bacilli. Hospital outbreaks of multi-drug resistant Enterobacteriaceae are now being frequently caused by extended spectrum beta-lactamase (ESBL) producers. Incidence of ESBL producing strains among clinical isolates has been steadily increasing over past years resulting in limitation of therapeutic options. Bacterial antibiotic resistance has become a major clinical concern worldwide including Bangladesh. Recently, the use of second and third generation cephalosporin has led to the selection of Gram-negative organisms resistant to ?-lactamase stable cephalosporin. This resistance is attributed to the production of extended spectrum ?-lactamases.DOI: http://dx.doi.org/10.3329/jcamr.v1i1.19560J Curr Adv Med Res 2014;1(1):13-19
L Advinda, Anhar, Irdawati
Journal of Physics: Conference Series · 2021
Abstract Siderophore is a chemical compound of Fe chelating. This compound is produced by several microorganisms that grow under iron-limiting conditions. Siderophore can facilitate the transfer of Fe from the environment to become available to plants. The siderophore ability to bind Fe as a competitor against other microorganisms, so that in the agricultural system it can be used as a plant disease controller. This study aims to determine the production of siderophore produced by several fluorescent pseudomonad isolates and its antagonistic tests against Blood Disease Bacteria (BDB). Siderohore detection is determined by the absorbance value obtained, and measured using a spectrophotometer at a wavelength of 410 nm. The antagonist test used a completely randomized designwith 7 treatments and 3 replications. The treatment is fluorescent pseudomonads isolates PfLAHP2, PfPb1, PfCas3, PfKd7, PfCas, PfPj1, and PfPj2. PfLAHP2 isolates produced the highest siderophore, which was 1.027, and the lowest isolate PfCas was 0.148. The antagonistic test of fluorescent pseudomonad against BDB showed that PfLAHP2 isolate produced the largest inhibitory zone, which was 1.042 cm.
Matthew I Hutchings, Barrie Wilkinson
Microbiota and Host · 2023
Many, if not all, plants and animals form mutually beneficial symbioses (mutualisms) with microbes and a subset of these mutualisms are defensive, in which the host provides food and housing in return for defence against disease. These symbioses typically involve antibiotic-producing bacteria, the best known of which are filamentous actinomycetes in the genera Streptomyces and Pseudonocardia and unicellular species in the genus Pseudomonas. Such mutualisms are likely to be widespread in nature, but they are best characterised in insects, which provide experimentally tractable models for studying symbiosis and microbiome formation because they typically host less complex microbial communities. Here, we examine the mutualisms formed between insects and antibiotic-producing bacteria using well-characterised examples, including digger wasps and their endosymbiotic Streptomyces species, attine ants and their mutualist Pseudonocardia species and Paederus beetles with their pederin-producing Pseudomonas species. We also discuss how searching such symbiotic niches can give insights into the evolution and functions of microbial specialised metabolites and provide new platforms for antibiotic discovery.
Kristie Tanner, Christian Abendrotht, Manuel Porcar
bioRxiv (Cold Spring Harbor Laboratory) · 2017
Lipases are key biocatalysts with important biotechnological applications. With the aim of isolating robust lipolytic microbial strains, we have analyzed the bacterial communities inhabiting two domestic extreme environments: a thermophilic sauna and a dishwasher filter. Scanning electron microscopy revealed biofilm-forming and scattered microorganisms in the sauna and dishwasher sample, respectively. A culture-independent approach based on 16S rRNA analysis indicated a high abundance of Proteobacteria in the sauna sample; and, a large amount of Proteobacteria, Firmicutes, Cyanobacteria and Actinobacteria in the dishwasher filter. With a culture-dependent approach, we isolated 48 bacterial strains, screened their lipolytic activities on media with tributyrin as the main carbon source, and finally selected five isolates for further characterization. These strains, all of them identified as members of the genus Bacillus, displayed optimum lipolytic peaks at pH 6.5 and with 1-2% NaCl, and the activity proved very robust at a wide range of pH (up to 11.5) and added NaCl concentrations (up to 4%). The thermal, pH and salt robustness of the selected isolates is a valuable attribute for these strains, which are promising as highly tolerant biodetergents. To our knowledge, this is the first report regarding the isolation from an indoor environment of Bacillus strains with a high potential for industry.
Ana Beatriz Souza Flor dos Santos, Manuele Figueiredo da Silva, João Xavier de Araújo-Júnior et al.
Current Drug Targets · 2021
Bacterial resistance has become a major global concern, affecting about 500, 000 individuals in 22 countries. Thus, it is clear that Gram-negative bacteria have been receiving more attention in this scenario. These bacteria perform several resistance mechanisms, such as modifying lipid A from lipopolysaccharides as a product of the mcr-1 gene expression. This gene was initially identified in animals; however, it quickly spread to humans, spreading to 70 countries. Mcr-1 gene attributes resistance to polymyxin B and colistin, which are drugs established as the last alternative to combat Enterobacteriaceae bacteria. Notwithstanding the prevalence and lack of antibiotic therapies for such bacteria, this article aimed to compile information about natural compounds against the resistance attributed by this gene, including the activity of isolated colistin or its associations with other antibiotics. Among the studies that evaluated colistin's synergistic action with other compounds, azidothymidine and isoalantholactone stood out. On the other hand, the paenipeptin 1 analog showed satisfactory activities when associated with other antibiotics. Besides, it is worth mentioning that molecular docking results between ostole and eugenol toward phosphoethanolamine transferase MCR-1 revealed that these compounds could interact with critical amino acid residues for the catalytic action of this enzyme. Based on this, natural agents' role is evident against infections caused by mcr-1-positive bacteria, directly contributing to the development of new effective pharmacotherapies.
Burak ALAYLAR, Mehmet KARADAYI
Iğdır Üniversitesi Fen Bilimleri Enstitüsü Dergisi · 2021
Plant growth promoting rhizobacteria (PGPR) have critical role in promoting plant growth and health with various mechanisms. Production of indole acetic acid (IAA) and 1-aminocyclopropane-1-carboxylate (ACC) deaminase activity are well-known plant growth promoting (PGP) properties. In the current study; A total of 48 morphologically distinct bacterial colonies were chosen during the isolation of bacteria from various rhizospheric wheat, maize and sainfoin soil samples from agricultural areas in Ağrı-Turkey. The bacteria were isolated from soil samples utilizing by culture-dependent techniques. Then, the strains were visualised for PGP activities such as production acetic acid IAA and ACC deaminase activity. The 16S rRNA sequence similarity of potential PGPR rhizospheric strains demonstrated that strains belong to species Bacillus, Pseudomonas, Microbacterium, Pseudarthrobacter, Arthrobacter and Enterobacter. Totally, 11 of 48 isolates exhibited highly IAA producing and ACC deaminase activity. These results show that IAA producing and ACC deaminase activity of local potential PGPR strains isolated from soil rhizospheric which can appropriate for sustainable agricultural applications in Ağrı province.
Kalyani Pullapukuri, Gopa Dinesh Reddy
· 2023
Biosurfactant is a structurally diverse group of surface-active molecules, synthesized by microorganisms. They are capable of reducing surface and interfacial tension with low toxicity, high specificity and biodegradability. The samples were enriched in nutrient agar containing diesel oil, serially diluted and poured on nutrient agar plate. Biosurfactant producing organisms were screened by using oil spreading method, Blood hemolysis test, Emulsification index (E24) and Drop collapse method. Out of 50 isolates, ten strains showed positive biosurfactant production. Another interesting finding in this study was the use of crude oil as hydrophobic substrate for the isolation of biosurfactant producing bacterial strains; this approach may be useful during the initial isolation of biosurfactant producing bacteria to reduce the number of strains to be screened. These strains were characterized by using different biochemical tests like Gram’s staining, IMVIC etc.
Matteo Bassetti, Antonio Vena, Barbara Larosa et al.
Current Opinion in Infectious Diseases · 2024
Purpose of review To discuss novel antibiotics under clinical development, focusing on agents showing in-vitro activity against metallo-β-lactamases (MBL)-producing carbapenem-resistant Gram-negative bacteria (CR-GNB). Recent findings Currently, only a few approved agents show activity, alone or in synergistic combinations, against MBL-producing CR-GNB. If approved by regulatory agencies in case of favorable results from ongoing (and, for some agents, already completed) phase-3 studies, some novel β-lactam/β-lactamase inhibitor (BL/BLI) combinations could become available in the next few years as additional important options for treating MBL-producing CR-GNB infections. Additional interesting agents that belong both to BL/BLI combinations and to antibiotic classes other than BL and BL/BLI combinations have also shown activity against MBL-producing CR-GNB, with most of them being in early phases of clinical development. Summary Improving the use of these novel agents through virtuous antimicrobial stewardship frameworks able to guarantee both the efficacious treatment of infections requiring their use and the avoidance of their use whenever not necessary remains a challenge of utmost importance that should not be overlooked.
, Nampon Arttaweeporn
· 2007
Biosurfactants are gaining more and more attention and have already been utilized for a number of important industrial applications due to their biodegradability, capability to be produced from renewable resources, good functionality under extreme conditions (particularly those pertaining tertiary crude-oil recovery), and good comatibity with human beings. From this research, a biosurfactant solution produced from Bacillus Subtilis PT4, isolated from an oil sludge, was studied for its properties. The surface tension of nutrient broth was reduced to 26.4 mN/m when PT4 was incubated with 2% palm oil at 37C, 51 hours, as compared to an incubation time of 36 hours with sludge oil, suggesting that PT4 is more compatible with sludge oil than with palm oil. The critical micelle concentration (CMC) of the produced biosurfactants, after cultivation for 51 hours, was found to be 25 mg/1, corresponding to a minimum surface tension of 26.4 mN/m. From the oil recovery results, the efficiency of the produced biosurfactants was 63.56% for motor oil and 59.10% for palm oil.
, Titarat Lertchaowayuth
· 2008
The inhibitory effect of Lactococcus lactis WNC20 (Ll. 20), a nisin producing lactic acid bacteria, on food-borne bacteria was investigated by testing in yoghurt as a food model, as compared to commercial starter, LC. Experimental groups comprised of control A (Ll. 20 as starter culture), control B (commercial starter culture, LC), control C (food-borne pathogen), treatment A (Ll. 20 and food-borne pathogen) and treatment B (LC and food-borne pathogen). Starter culture inoculum of ~6-7- log cycle was used for all experiments. After 48 hours, Staphylococcus aureus ATCC25923 was not detected in treatment A after addition either at 2- or 3- log cycle. While, addition of S. aureus at 4- log cycle, S. aureus decreased 2- log cycle after 24 hours of incubation. However, no detection of S. aureus was observed in treatment B after 48 hours. With regard to, Bacillus cereus ATCC1729, Listeria monocytogenes DMST17303, Escherichia coli ATCC25922 and Salmonella Typhimurium ATCC13311, at 2-, 3- or 4- log cycles, were added into milk at the same time as the starter culture. Lis. monocytogenes was not detected in both treatment A and B after 48 hours incubation. B. cereus was inhibited at 16 hours incubation and increased to 5- log cycle at 48 hours in treatment A when added B. cereus at 2- and 3- log cycles. While, addition B. cereus 4- log cycle, it was inhibited after 16 hours and increased to 5- log cycle after 24 hours in treatment A. B. cereus in treatment B was not detected after 8 hours of incubation, added B. cereus starting at 2-, 3- and 4- log cycles. No viable cell of E. coli (<10 CFU/mL) in treatment A was detected after 72 hours, but in treatment B E. coli was inhibited after 48 hours. With regard to, Sal. Typhimurium starting at 2- and 3- log cycles was not detected after 24 hours of incubation yoghurt, and after 72 hours for adding 4- log cycle in treatment A. Whereas, in treatment B Sal. Typhimurium was not detected after 16 and 24 hours for adding 2-, 3- and 4- log cycles, respectively. All experiments found that pH always decreased whereas percentage of total acid always increased throughout the experiment. Nisin Z was also found from yoghurt Ll. 20, which showed inhibition on, Lb. plantarum TISTR850 growth by agar diffusion technique. Therefore, Ll. 20 could be used as starter in Nham preparatAAion in order to reduce food-borne bacteria contamination.
Pradeep Kumar Singh Sandesh Chibber, Veerendra Singh Nagoria
International Journal of Current Microbiology and Applied Sciences · 2022
Biosurfactants having the characteristics of amphipathic compounds. Biosurfactants are produced by several microorganisms which include Acinetobacter spp., Bacillus spp., Candida antarctica, Pseudomonas aeruginosa. Different screening methods, for example oil spreading assay, blood agar hemolysis, emulsification assay, foaming activity are used to select biosurfactant producing microbes. The main objective of this research work was to isolate and characterize the biosurfactant producing bacteria from oil contaminated soil. By using kerosene oil as the sole carbon source, bacterial strain was isolated and screened having the characteristics of biosurfactant properties. Number of techniques like oil spreading technique, blood hemolysis test, foaming activity, and emulsification activity were performed for the screening of the biosurfactant producing bacteria, and found positive oil spreading technique in bacterial strain B1 and B2. Strain B1 (52%) has high emulsifying activity, whereas in B2 it was around 42 %. Strain B1 showed complete breakdown of the hemoglobin of the red blood cells in the vicinity of bacterial colony i.e. β blood hemolysis test and in B2 it is lack of hemolysis i.e. γ hemolysis. It was observed that foaming stability in B2 strain is lesser than B2. Both the isolated bacterial strains B1 and B2 showed Gram positive, and they are in rod and circular shape respectively. From the result of various biochemical characterization and cell morphological characterization, the isolated strain was bacillus type bacteria.