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The main objective of the study was to investigate the viability of utilizing ultrasonically pretreated water hyacinth (Eichhornia crassipes) biomass as a sustainable source for power production via the application in microbial fuel cells (MFCs). This treatment aims to address the challenges associated with water hyacinth management while simultaneously offering a viable solution to the prevailing issues of energy shortage and power inadequacy. Ultrasonic treatment was used to pretreat water hyacinth, since it is capable of deconstructing lignocellulose biomass and has the distinct advantage of being both energy-efficient and cost-effective. The use of ultrasonic treatment to mitigate and control the growth of water hyacinth has been investigated as a possible strategy. Using high-frequency sound waves, usually above human hearing (20 kHz), ultrasonic therapy breaks down the cellular structure of the plants biomass. A decrease in chemical oxygen demand of 91.1% and Coulombic efficiency of 11% was observed. The electrochemical analysis, electrochemical impedance spectroscopy, cyclic voltammetry, power density, and current density were assessed under optimal experimental circumstances and in the presence of preisolated electroactive bacteria Pseudomonas aeruginosa. At a substrate concentration of 7 g/L, the highest power density of 9.7 W/m3was attained along with an internal resistance of 89.5 Ω. This study reveals that water hyacinth biomass is one of the most plentiful renewable energy resources and a possible alternative to fossil fuels.

A successful agro-waste management system may recover energy and stabilize waste, among other benefits. The purpose of this research was to analyze the microbiological decomposition of cellulose that has been alkaline extracted and bleached from wheat bran byproducts. The waste lignin stream was used to synthesize biochar for anode modification. Fourier transform infrared spectroscopy showed that O-H and C-H functional groups predominated in extracted cellulose, whereas scanning electron microscopy, X-ray diffraction, and Raman microscopy characterized lignin-derived biochar and cellulose. Pantoea dispersa, isolated from cow dung, was identified as a cellulose-degrading bacteria using 16 S rRNA sequencing. Cellulose-degrading efficiency was measured by hydrolysis zone size around bacterial colonies. To facilitate cellulose breakdown and sustained power production in a microbial fuel cell, the cellulose-degrading bacteria were co-cultured with the Pseudomonas aeruginosastrain at a 1:1 ratio. Cyclic voltammetry, electrochemical impedance spectroscopy, power density, and current density have been investigated under ideal conditions. At a substrate concentration of 2.5 gm/L and internal resistance of 69.5Ω, a modified anode achieved the maximum power density of 9.1 W/m3. Using agro-waste for waste-to-energy is a step toward a circular bioeconomy.

The present state of energy scarcity and the intensified greenhouse impact resulting from carbon dioxide emissions have prompted significant apprehension over the capture and utilization of carbon dioxide. The utilization of exoelectrogenic bacteria within an electrochemical framework has positioned microbial electrolysis cells (MECs) as a promising alternative for the bioelectrochemical conversion of CO2into low-carbon electro fuels such as CH4. By employing this approach, not only may CO2be sequestered, but it also presents an opportunity to harness and utilize energy. The integration of a MEC with a traditional anaerobic digester (AD) is employed in the novel process of electromethanogenesis, facilitating the production of bio-methane. Following the discovery that both cathodic and anodic bacteria possess the capability to generate methane, subsequent research endeavours were undertaken to enhance the efficiency of this process. This was achieved by optimizing several parameters, including microbial species selection, biofilm formation, substrate sources, and electrode surface characteristics. The intriguing nature of microbial composition in MECs as biocatalysts, along with their remarkable capacity to assimilate various essential nutrients, renders them highly captivating. As a result of extensive research conducted in this particular domain, a multitude of MECs have been devised to facilitate the biodegradation of organic compounds and the subsequent generation of hydrogen. This paper undertakes a comprehensive assessment of the existing MEC-AD vaccination and launch methods. Subsequently, the system design and scale-up details are provided, along with pertinent information regarding the selected electrode materials, their respective surface areas, and surface chemistry, as well as the inter-electrode spacing.

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Due to its richness and carbon neutrality, biomass is emerging as a useful resource in the hunt for renewable energy sources. The process of pyrolysis is widely used to transform biomass into useful hydrocarbons or alternative energy sources. Lignocellulosic biomass is a renewable energy source that is high in carbon. This review article describes the pyrolysis process, which includes biomass pre-treatment, pyrolysis mechanism, and process product upgrading. The pre-treatments of bio material using chemical and physical methods are investigated. One of the ineffective methods for transforming lignocellulosic biomass—which contains components of hemicellulose, cellulose, and lignin—into solids, liquids, and gases is pyrolysis. The pyrolysis conversion mechanism includes the production of char, depolymerization, fragmentation, and several secondary reactions. Research gaps are also identified, along with suggestions for improving pre-treatment methods. It is also described how the performance of the pyrolysis process is affected by the properties of the feedstock, operating parameters, and biomass kinds. Using a few research concepts, rapid progress in pyrolysis instrument identification is discussed. This study starts with a review of the chemistry of contemporary lignocellulose pyrolysis and moves on to the production of various products like oil, gas, and char.

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Bio-based materials from bark, wood, leaves, and fruits have several uses in nanotechnology. Anthocephalus Cadamba is a biological reducing agent in nanocomposites. The fruit of Anthocephalus Cadamba is used to synthesize ZnO nanoparticles and polyaniline to make a ZnO-PANI nanocomposite. We describe UV–visible, FTIR, XRD, and SEM data to support synthesis. The dielectric constant is highest in the ZnO-PANI nanocomposite compared to pure ZnO nanoparticles. The Nyquist plot semicircular arc confirms temperature-induced conductivity improvement in nanocomposites. Nanocomposites have 1.3 ×10−2S/m higher conductivity than nanoparticles. The ZnO-PANI nanocomposite has the greatest specific capacitance (Csp) of 1.3 × 10−2. This work suggests that ZnO-PANI nanocomposite electrodes might be useful supercapacitors in energy storage devices with antibacterial properties. XTT assay and biofilm formation assay using CLSM (Confocal laser scanning microscope) indicated that Integration of ZnO-PANI nanocomposites onto biofilm-prone surfaces like medical devices or implants inhibited bacteria adhesion and biofilm growth in antimicrobial investigations.

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Biosurfactants are biomolecules produced by microorganisms, low in toxicity, biodegradable, and relatively easy to synthesize using renewable waste substrates. Biosurfactants are of great importance with a wide and versatile range of applications, including the bioremediation of contaminated sites. Plants may accumulate soil potentially toxic elements (PTEs), and the accumulation efficacy may be further enhanced by the biosurfactants produced by rhizospheric microorganisms. Occasionally, the growth of bacteria slows down in adverse conditions, such as highly contaminated soils with PTEs. In this context, the plant's phytoextraction capacity could be improved by the addition of metal-tolerant bacteria that produce biosurfactants. Several sources, categories, and bioavailability of PTEs in soil are reported in this article, with the focus on the cost-effective and sustainable soil remediation technologies, where biosurfactants are used as a remediation method. How rhizobacterial biosurfactants can improve PTE recovery capabilities of plants is discussed, and the molecular mechanisms in bacterial genomes that support the production of important biosurfactants are listed. The status and cost of commercial biosurfactant production in the international market are also presented.

Occupational exposure to pesticides has been associated with adverse health conditions, including genotoxicity and cancer. Nullity of GSTT1/GSTM1 increases the susceptibility of pesticide workers to these adverse health effects due to lack of efficient detoxification process created by the absence of these key xenobiotic metabolizing enzymes. However, this assertion does not seem to maintain its stance at all the time; some pesticide workers with the null genotypes do not present the susceptibility. This suggests the modulatory role of other confounding factors, genetic and environmental conditions. Pesticides, aggravated by the null GSTT1/GSTM1, cause genotoxicity and cancer through oxidative stress and miRNA dysregulation. Thus, the absence of these adverse health effects together with the presence of null GSTT1/GSTM1 genotypes demands further explanation. Also, understanding the mechanism behind the protection of cells - that are devoid of GSTT1/GSTM1 - from oxidative stress constitutes a great challenge and potential research area. Therefore, this review article highlights the recent advancements in the presence and absence of cancer risk in occupational pesticide workers with GSTT1 and GSTM1 null genotypes.

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One Health is a comprehensive and cohesive strategy that seeks to effectively manage and enhance the well-being of people, animals, and ecosystems in a sustainable manner. Electrochemical biosensors are indispensable vectors for One Health management, with diverse applications across industrial process control, environmental monitoring, healthcare, microbiology, and quality assurance. The integration of nanotechnology has propelled innovative sensing algorithms, enhancing the efficiency and precision of biosensors. Nanoscale material integration amplifies their ability to detect molecules and single biomolecules with nano-biosensors utilizing nanoparticles, nanowires, carbon nanotubes (CNTs), nanorods, and quantum dots. Nanomaterials, distinguished by surface functionalities, tunability of physical/chemical properties, high detection sensitivity, large surface area, stability, and thermal/electrical conductivity, are instrumental in architecting nano-biosensors. The main limitations in current times are scalability, cross-sensitivity, complex immobilization pathways, and the toxicity factor of nanosensors, which are hazardous for the ecosystem as well as humans. This review explores the fundamentals of nanotechnology-enabled electrochemical biosensors, encompassing their composition, manufacturing materials, and diverse applications, highlighting their necessity in advancing biosensor technology to control environmental contamination/human diseases in order to manage One Health.

Microbial fuel cell (MFC) technology has been investigated for over a decade now and it has been deemed as a preferred technique for energy generation since it is environmentally benign and does not produce toxic by/end products. However, this technology is characterized by low power outputs, poor microbial diversity detection, and the presence of methanogenic microorganisms, poor electrochemically active microorganisms’ enrichment techniques, and the type of electrode that is used, amongst others. Furthermore, this technology has relied mostly on refined chemicals for energy production and this practice is not sustainable for long-term application of this technology. This paper reviews the use of a microalgae-assisted MFC for a self-sustainable microbial fuel cell where a microalgae-assisted cathode is established to facilitate the oxidation/reduction reactions (ORR) while recycling the generated algal biomass to the anode compartment as a feedstock for improved energy generation. Furthermore, this review proposes for the utilization of cell disruption techniques to maximize nutrient availability for maximal power generation while also making use of molecular diagnostic tools such as metagenomics and metatranscriptomics to monitor the microbial community structure and function.

Microbial Desalination Cell (MDC) is an innovative approach for water desalination that concurrently produces energy through the process of substrate oxidation. The primary issue of the technique is its limited power on capabilities during the oxygen reduction reaction (ORR). While the depletion of oxygen is a significant process in electrochemical energy conversion, its slow kinetics hinder its utilization in MDCs. One potential resolution to this problem is the utilization of a cathode catalyst with a high level of activity, which effectively enhances the rate of ORR. Different concentrations of copper oxide (CuO) nanoparticles (NPs) were used to investigate the behavior of ORR and its impact on the performance of the MDC. The optimal concentration of silver oxide (AgO) NPs was utilized to conduct a comparative analysis of both types of NPs. The size of CuO NPs and AgO NPs was found to be 65nm and 55nm respectively by material characterization studies. The power density achieved in the absence of the catalyst was 1.1W/m3, and this value increased to 4.9W/m3with the incorporation of 3mg/cm2AgO. The use of a catalyst loading of 3mg/cm2has been determined to be efficacious in enhancing the desalination rate in MDC. The electrochemical investigations conducted also showed an improvement in the electrocatalytic behavior of cathodic kinetics while operating under these specific afterward. Therefore, the utilization of AgO catalyst exhibits potential as a viable option for the expansion of MDC processes, thereby contributing to the achievement of sustainable development objectives.

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Microbial fuel cells (MFCs) are emerging as a sustainable technology for waste to energy conversion where electrode materials play a vital role on its performance. Platinum (Pt) is the most common material used as cathode catalyst in the MFCs. However, the high cost and low earth abundance associated with Pt prompt the researcher to explore inexpensive catalysts. The present study demonstrates a noble metal-free MFC using a manganese ferrite (MnFe2O4)/polyaniline (PANI)-based electrode material. The MnFe2O4nanoparticles (NPs) and MnFe2O4NPs/PANI hybrid composite not only exhibited superior oxygen reduction reaction (ORR) activity for the air cathode but also enhanced anode half-cell potential upon modifying carbon cloth anode in the single-chambered MFC. This is attributed to the improved extracellular electron transfer of exoelectrogens due to Fe3+in MnFe2O4and its capacitive nature. The present work demonstrates for the first time the dual property of MnFe2O4NPs/PANI, i.e., as cathode catalyst and an anode modifier, thereby promising cost-effective MFCs for practical applications.

Nanoparticles have received much attention in biomedical applications due to their unique physicochemical properties. The metal/metal oxide nanoparticles are involved in various applications, including drug delivery, therapy, and diagnosis. Subsequently, many hazardous chemicals and organic solvents were utilized to synthesize the metallic nanoparticles. Therefore, the green synthesis came into the limelight to overcome the economic and environmental burden. The green synthesis represents the production of nanoparticles that reduce or terminate the use of hazardous materials and solvents that encourages environmental safety. The frequently utilized green materials in numerous metallic nanoparticle syntheses include microbes, plants, fruits, and other food sources. However, the burden on global food security and limited natural resources creates distress over environmental sustainability. Thus, adopting bio-waste materials to produce highly efficient, biocompatible, economic, and eco-friendly metallic nanoparticles could support waste valorization and lead to environmental sustainability. Therefore, the present review focuses on the various bio-waste materials adopted to synthesize metal/metal oxide nanoparticles. We have thoroughly discussed the potential of chemicals-mediated metal/metal oxide nanoparticles in different drug delivery applications such as tumor targeting, brain targeting, stimuli-responsive drug release followed by large molecules delivery. Consequently, this can open a new road for researchers to explore drug delivery applications using bio-waste mediated green synthesized metallic nanoparticles. Finally, the cytotoxicity aspects of such nanoparticles are meticulously discussed compared to chemically synthesized counterparts.

•Electron transfer mechanism elaborated for various fungal species.•Application of fungi as a cathode and anode catalyst is discussed.•Different factors affecting on performance of fungi based MES are reviewed.•Fungi are classified based on their electron transfer mechanism.

In recent years, research initiatives on renewable bioenergy or biofuels have been gaining momentum, not only due to fast depletion of finite reserves of fossil fuels but also because of the associated concerns for the environment and future energy security. In the last few decades, interest is growing concerning microalgae as the third-generation biofuel feedstock. The CO2fixation ability and conversion of it into value-added compounds, devoid of challenging food and feed crops, make these photosynthetic microorganisms an optimistic producer of biofuel from an environmental point of view. Microalgal-derived fuels are currently being considered as clean, renewable, and promising sustainable biofuel. Therefore, most research targets to obtain strains with the highest lipid productivity and a high growth rate at the lowest cultivation costs. Different methods and strategies to attain higher biomass and lipid accumulation in microalgae have been extensively reported in the previous research, but there are fewer inclusive reports that summarize the conventional methods with the modern techniques for lipid enhancement and biodiesel production from microalgae. Therefore, the current review focuses on the latest techniques and advances in different cultivation conditions, the effect of different abiotic and heavy metal stress, and the role of nanoparticles (NPs) in the stimulation of lipid accumulation in microalgae. Techniques such as genetic engineering, where particular genes associated with lipid metabolism, are modified to boost lipid synthesis within the microalgae, the contribution of “Omics” in metabolic pathway studies. Further, the contribution of CRISPR/Cas9 system technique to the production of microalgae biofuel is also briefly described.

In the last two decade, there is extensive research carried out for improving the microbial electrochemical systems (MES) performance in terms of both wastewater treatment and product generation along with its upscaling for industrial application. During the scale-up of these technologies, various economic problems regarding process feasibility have been investigated. This economic feasibility needs to be valued in terms of efficiency and environmental sustainability, because of which these technologies have been studied in the first place. A systematic review was conducted highlighting both parameters, i.e., the economics and environmental sustainability in the form of techno-economic assessment of these systems and also showing a comparative study between microbial fuel cells, microbial electrolysis cells, microbial electrosynthesis cells, and microbial desalination cells, against the conventional technologies on the basis on these parameters. Based on the study, the conventional technologies require less operational and maintenance cost but also less environmentally sustainable in comparison to these MES. The most common tool for the assessment of the environmental performance of a process or product is the life cycle analysis. This article summarizes the techno-economic assessment of microbial fuel cells, Microbial electrolysis cells, microbial electrosynthesis cells, and microbial desalination cells. This article concludes that further research is required in terms of scale-up and reducing the overall costs of these MES for efficiently incorporating for practical usage.