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Self-powered biosensors with high sensitivity have garnered significant interest for their potential applications in the realm of portable sensing. Herein, a self-powered biosensor with a novel signal amplification strategy was developed by integrating target-controlled release of mediator with an enzyme biofuel cell for the ultrasensitive detection of acetamiprid (ACE). Zeolitic imidazolate framework-67 was utilized as both a nanocontainer for capturing the electron mediator 2,2'-azidobis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), and a precursor for the synthesis of cobalt nanoparticles/nitrogen, sulfur-codoped carbon nanotubes (Co NPs/NS-CNTs), which were employed as the electrode material for constructing both the glucose oxidase-based bioanode and the laccase-based biocathode. The target analyte ACE can specifically bind to its aptamer, leading to the release of ABTS, which cyclically participates in the catalytic reaction of the biocathode, thereby amplifying the electrochemical signal. By leveraging the benefits of ABTS cyclic catalysis and the effective electrocatalysis of bioelectrodes based on Co NPs/NS-CNTs, the self-powered biosensor has a broad detection range of 0.1-1000 fM and a low detection limit of 25 aM toward ACE. The proposed signal amplification approach presents a promising strategy for enhancing sensitivity and enabling portable analysis in applications of food safety, environmental monitoring, and medical diagnostics.
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Técnicas Biossensoriais , Eletrodos , Glucose Oxidase , Lacase , Neonicotinoides , Neonicotinoides/análise , Neonicotinoides/química , Técnicas Biossensoriais/métodos , Lacase/química , Lacase/metabolismo , Glucose Oxidase/química , Glucose Oxidase/metabolismo , Nanotubos de Carbono/química , Técnicas Eletroquímicas/métodos , Limite de Detecção , Estruturas Metalorgânicas/química , Cobalto/química , Ácidos Sulfônicos/química , Benzotiazóis/química , Zeolitas/química , Nanopartículas Metálicas/química , Aptâmeros de Nucleotídeos/química , Fontes de Energia BioelétricaRESUMO
Flap endonuclease 1 (FEN1) is a structure-specific endonuclease that plays a critical role in the maintenance of genome integrity. In this work, we demonstrate a novel self-powered electrochemical FEN1 biosensor for potential applications in molecular diagnosis. Porous Fe3O4 nanoparticles are first prepared, and single-strand DNA probes are absorbed on the surface of the nanoparticles. Thus, electrochemical species of [Fe(CN)6]3- can be encapsulated inside the porous nanoparticles with the molecular gate of negatively charged DNA. On the other hand, a dumbbell structured DNA probe with 5' flap is designed. FEN1 is able to cleave the flap and activate the CRISPR/Cas system for the digestion of single-stranded DNA around Fe3O4 nanoparticles. As a result, the leakage of [Fe(CN)6]3- contributes to an enhanced electrochemical response, which can be used to reveal the level of FEN1. The high sensitivity of this biosensor is due to the application of porous nanomaterials and Mn2+ accelerated CRISPR/Cas cleavage. It succeeds in detection of biological samples and screening of FEN1 inhibitors. Therefore, this proposed method has potential applications in the early diagnosis of diseases and drug discovery.
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Industrialization and globalization have increased the demand for petroleum products that has increased a load on natural energy resources. The escalating fossil fuel utilization has resulted in surpassing the Earth's capacity to absorb greenhouse gases, necessitating the exploration of sustainable bioenergy alternatives to mitigate emissions. Biofuels, derived from algae, offer promising solutions to alleviate fossil fuel dependency. Algae, often regarded as third-generation biofuels, present numerous advantages owing to their high biomass production rates. While algae have been utilized for their bioactive compounds, their capability as biomass for the production of biofuel has gained traction among researchers. Various biofuels such as bio-hydrogen, bio-methane, bio-ethanol, bio-oil, and bio-butanol can be derived from algae through diverse processes like fermentation, photolysis, pyrolysis, and transesterification. Despite the enormous commercial potential of algae-derived biofuels, challenges such as high cultivation costs persist. However, leveraging the utilization of algae byproducts could improve economic viability of biofuel production. Moreover, algae derived biofuels offer environmental sustainability, cost-effectiveness, and waste reduction benefits, promising novel opportunities for a more sustainable energy future.
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Biofuel production has emerged as a leading contender in the quest for renewable energy solutions, offering a promising path toward a greener future. This comprehensive state-of-the-art review delves into the current landscape of biofuel production, exploring its potential as a viable alternative to conventional fossil fuels. This study extensively examines various feedstock options, encompassing diverse sources such as plants, algae, and agricultural waste, and investigates the technological advancements driving biofuel production processes. This review highlights the environmental benefits of biofuels, emphasizing their capacity to significantly reduce greenhouse gas emissions compared to those of fossil fuels. Additionally, this study elucidates the role of biofuels in enhancing energy security by decreasing reliance on finite fossil fuel reserves, thereby mitigating vulnerabilities to geopolitical tensions and price fluctuations. The economic prospects associated with biofuel production are also elucidated, encompassing job creation, rural development, and the potential for additional revenue streams for farmers and landowners engaged in biofuel feedstock cultivation. While highlighting the promise of biofuels, the review also addresses the challenges and considerations surrounding their production. Potential issues such as land use competition, resource availability, and sustainability implications are critically evaluated. Responsible implementation, including proper land-use planning, resource management, and adherence to sustainability criteria, is emphasized as critical for the long-term viability of biofuel production. Moreover, the review underscores the importance of ongoing research and development efforts aimed at enhancing biofuel production efficiency, feedstock productivity, and conversion processes. Technological advancements hold the key to increasing biofuel yields, reducing production costs, and improving overall sustainability. This review uniquely synthesizes the latest advancements across the entire spectrum of biofuel production, from feedstock selection to end-use applications. It addresses critical research gaps by providing a comprehensive analysis of emerging technologies, sustainability metrics, and economic viability of various biofuel pathways. Unlike previous reviews, this work offers an integrated perspective on the interplay between technological innovation, environmental impact, and socio-economic factors in biofuel development, thereby providing a holistic framework for future research and policy directions in renewable energy.
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Biocomponents (such as lipids) accumulate in oleaginous microorganisms and could be used for renewable energy production. Oleaginous microbes are characterized by their ability to accumulate high levels of lipids, which can be converted into biodiesel. The oleaginous microbes (including microalgae, bacteria, yeast, and fungi) can utilize diverse substrates. Thus, in this study, commercially viable oleaginous microorganisms are comparatively summarized for their growth conditions, substrate utilization, and applications in biotechnological processes. Lipid content is species-dependent, as are culture conditions (such as temperature, pH, nutrients, and culture time) and substrates. Lipid production can be increased by selecting suitable microorganisms and substrates, optimizing environmental conditions, and using genetic engineering techniques. In addition, the emphasis on downstream processes (including harvesting, cell disruption, lipid extraction, and transesterification) highlights their critical role in enhancing cost-effectiveness. Oleaginous microorganisms are potential candidates for lipid biosynthesis and could play a key role in meeting the energy needs of the world in the future.
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Bactérias , Biocombustíveis , Fungos , Metabolismo dos Lipídeos , Microalgas , Energia Renovável , Biocombustíveis/microbiologia , Microalgas/metabolismo , Bactérias/metabolismo , Bactérias/genética , Fungos/metabolismo , Biotecnologia/métodos , Lipídeos/biossínteseRESUMO
The use of biodiesel as an alternative to conventional diesel fuels has gained significant attention due to its potential for reducing greenhouse gas emissions and improving energy sustainability. This study explores the impact of TiO2 nanoparticles on the emission characteristics and combustion efficiency of biodiesel blends in compression ignition (CI) engines. The fuels analyzed include diesel, SB20 (soybean biodiesel), SB20 + 50 TiO2 ppm, SB20 + 75 TiO2 ppm, PB20 (palm biodiesel), PB20 + 50 TiO2 ppm, and PB20 + 75 TiO2 ppm. Experiments were conducted under a consistent load of 50% across engine speeds ranging from 1000 to 1800 RPM. While TiO2 nanoparticles have been widely recognized for their ability to enhance biodiesel properties, limited research exists on their specific effects on soybean and palm biofuels. This study addresses these gaps by providing a comprehensive analysis of emissions, including NOX, CO, CO2, and HC, as well as exhaust gas temperature (EGT), across various engine speeds and nanoparticle concentrations. The results demonstrate that TiO2 nanoparticles lead to a reduction in CO emissions by up to 30% and a reduction in HC emissions by 21.5% at higher concentrations and engine speeds. However, this improvement in combustion efficiency is accompanied by a 15% increase in CO2 emissions, indicating more complete fuel oxidation. Additionally, NOX emissions, which typically increase with engine speed, were mitigated by 20% with the addition of TiO2 nanoparticles. Exhaust gas temperatures (EGTs) were also lowered, indicating enhanced combustion stability. These findings highlight the potential of TiO2 nanoparticles to optimize biodiesel blends for improved environmental performance in CI engines.
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Addressing global environmental challenges and meeting the escalating energy demands stand as two pivotal issues in the current landscape. Lignocellulosic biomass emerges as a promising renewable bio-energy source capable of fulfilling the world's energy requirements on a large scale. One of the most important steps in lowering reliance on fossil fuel and lessening environmental effect is turning lignocellulosic biomass into biofuel. As carbon-neutral substitutes for traditional fuel, biofuel offer a solution to environmental concerns compared to conventional fuel. Effective utilization of lignocellulosic biomass is imperative for sustainable development. Ongoing research focuses on exploring the potential of various microorganisms and their co-interactions to synthesize diverse biofuels from different starting materials, including lignocellulosic biomass. Co-culture techniques demonstrate resilience to nutrient scarcity and environmental fluctuations. By utilising a variety of carbon sources, microbes can enhance their adaptability to environmental stressors and potentially increase productivity through their symbiotic interactions. Furthermore, compared to single organism involvement, co-interactions allow faster execution of multistep processes. Lignocellulosic biomass serves as a primary substrate for pre-treatment, fermentation, and enzymatic hydrolysis processes. This review primarily delves into the pretreatment, enzymatic hydrolysis process and the biochemical pathways involved in converting lignocellulosic biomass into bioenergy.
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Biocombustíveis , Biomassa , Lignina , Lignina/metabolismo , Bactérias/metabolismo , Fermentação , Hidrólise , Técnicas de CoculturaRESUMO
Enzymatic biofuel cells (EBFC) are promising sources of green energy owing to the benefits of using renewable biofuels, eco-friendly biocatalysts, and moderate operating conditions. In this study, a simple and effective EBFC was presented using an enzymatic composite material-based anode and a nonenzymatic bimetallic nanoparticle-based cathode respectively. The anode was constructed from a glassy carbon electrode (GCE) modified with a multi-walled carbon nanotube (MWCNT) and ferrocene (Fc) as a conductive layer coupled with the enzyme glucose oxidase (GOx) as a sensitive detection layer for glucose. A chitosan layer was also applied to the electrode as a protective layer to complete the composite anode. Chronoamperometry (CA) results show that the MWCNT-Fc-GOx/GCE electrode has a linear relationship between current and glucose concentration, which varied from 1 to 10 mM. The LOD and LOQ were calculated for anode as 0.26 mM and 0.87 mM glucose, respectively. Also the sensitivity of the proposed sensor was calculated as 25.71 µ A/mM. Moreover, the studies of some potential interferants show that there is no significant interference for anode in the determination of glucose except ascorbic acid (AA), uric acid (UA), and dopamine (DA). On the other hand, the cathode consisted of a disposable pencil graphite electrode (PGE) modified with platinum-palladium bimetallic nanoparticles (Nps) which exhibit excellent conductivity and electron transfer rate for the oxygen reduction reaction (ORR). The constructed EBFC was optimized and characterized using various electroanalytical techniques. The EBFC consisting of MWCNT-Fc-GOx/GCE anode and Pt-PdNps/PGE cathode exhibits an open circuit potential of 285.0 mV and a maximum power density of 32.25 µW cm-2 under optimized conditions. The results show that the proposed EBFC consisting of an enzymatic composite-based anode and bimetallic nanozyme-based cathode is a unique design and a promising candidate for detecting glucose while harvesting power from glucose-containing natural or artificial fluids.
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The oil contents and fatty acid composition of three non-edible seed oils extracted using Soxhlet extraction with hexane as the solvent were presented. The physical and chemical properties of the oils were determined from which cetane number, biofuel potential, higher heating values, and antimicrobial activities were assessed. The dominant fatty acids were 49 % linoleic acid, 37 % pentadecenoic acid, and 38 % cis-10-heptadecenenoic acid for Hura crepitans (HC), Thevetia nerifolia (TN) and Trichosanthes cucumerina (TC), respectively. The seed oils were majorly unsaturated, with HC having the highest degree of unsaturation. Acid value, saponification value, iodine value, and free fatty acids were low compared to many reported values in literature. The cetane values were generally high because the oils have a reasonable amount of saturated fatty acid, with TN having the highest cetane number. The low iodine value and saponification value make the biofuel potential and higher heating value to be high with TN having the highest in both and thus the best seed oil for biofuel. However, TN and HC have no antimicrobial activity to Klebsiella pneumoniae (gram -ve), Staphylococcus aureus (gram +ve), Escherichia coli (gram -ve), Bacillus subtilis, Enterobacter aerogenes, Candida albican, Rhizopus stolonifer, Fusarium Solani, Aspergillus flavus and Candida tropicalis, while TC has broad spectrum of activity against all tested bacteria and fungi, except Klebsiella pneumoniae.
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1,8-Cineole has a potential in control crop pests and biofuels. The endophytic fungus, Annulohypoxylon sp. FPYF3050 (Neolitsea pulchella), can produce over 90% 1,8-cineole of relative area in its natural volatiles, possessed nematicide properties. The annotated genome of this strain will provide insights into potential application in biofumigation and terpene-based advanced biofuel.
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The aim of this study was to investigate the effects of various concentrations of antioxidants, including butyl hydroxy anisd (BHA), butylated hydroxytoluene (BHT), fulvic acid (FA), melatonin (MT), glycine betaine (GB) and putrescine (Put), on growth and lipid synthesis of microalgae under low-temperature (15 â). Changes in biochemical indicators, reactive oxygen species (ROS) level, glutathione (GSH) content and antioxidant enzyme activities were also studied. The results indicated that the maximum biomass concentration (1.3 g/L) and lipid productivity (75.3 ± 5.8 mg/L d-1) were achieved under 100 µM MT and 1 µM GB, respectively. Moreover, antioxidants were able to increase the GSH and antioxidant enzymes activities in algal cells under low-temperature stress. This study was enlightening for the utilization of antioxidants to improve the resistance to low-temperature stress and lipid production in microalgae, and provided a theoretical basis for the application of microalgae for lipid accumulation in cold regions.
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Antioxidantes , Temperatura Baixa , Microalgas , Espécies Reativas de Oxigênio , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Microalgas/efeitos dos fármacos , Microalgas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Lipídeos/biossíntese , Biomassa , Estresse Fisiológico/efeitos dos fármacos , Glutationa/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacosRESUMO
BACKGROUND: Production of cheese whey in the EU exceeded 55 million tons in 2022, resulting in lactose-rich effluents that pose significant environmental challenges. To address this issue, the present study investigated cheese-whey treatment via membrane filtration and the utilization of its components as fermentation feedstock. A simulation model was developed for an industrial-scale facility located in Italy's Apulia region, designed to process 539 m3/day of untreated cheese-whey. The model integrated experimental data from ethanolic fermentation using a selected strain of Kluyveromyces marxianus in lactose-supplemented media, along with relevant published data. RESULTS: The simulation was divided into three different sections. The first section focused on cheese-whey pretreatment through membrane filtration, enabling the recovery of 56%w/w whey protein concentrate, process water recirculation, and lactose concentration. In the second section, the recovered lactose was directed towards fermentation and downstream anhydrous ethanol production. The third section encompassed anaerobic digestion of organic residue, sludge handling, and combined heat and power production. Moreover, three different scenarios were produced based on ethanol yield on lactose (YE/L), biomass yield on lactose, and final lactose concentration in the medium. A techno-economic assessment based on the collected data was performed as well as a sensitivity analysis focused on economic parameters, encompassing considerations on cheese-whey by assessing its economical impact as a credit for the simulated facility, dictated by a gate fee, or as a cost by considering it a raw material. The techno-economic analysis revealed different minimum ethanol selling prices across the three scenarios. The best performance was obtained in the scenario presenting a YE/L = 0.45 g/g, with a minimum selling price of 1.43 /kg. Finally, sensitivity analysis highlighted the model's dependence on the price or credit associated with cheese-whey handling. CONCLUSIONS: This work highlighted the importance of policy implementation in this kind of study, demonstrating how a gate fee approach applied to cheese-whey procurement positively impacted the final minimum selling price for ethanol across all scenarios. Additionally, considerations should be made about the implementation of the simulated process as a plug-in addition in to existing processes dealing with dairy products or handling multiple biomasses to produce ethanol.
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The elevated level of carbon dioxide in the atmosphere has become a pressing concern for environmental health due to its contribution to climate change and global warming. Simultaneously, the energy crisis is a significant issue for both developed and developing nations. In response to these challenges, carbon capture, sequestration, and utilization (CCSU) have emerged as promising solutions within the carbon-neutral bioenergy sector. Numerous technologies are available for CCSU including physical, chemical, and biological routes. The aim of this study is to explore the potential of CCSU technologies, specifically focusing on the use of microorganisms based on their well-established metabolic part. By investigating these biological pathways, we aim to develop sustainable strategies for climate management and biofuel production. One of the key novelties of this study lies in the utilization of microorganisms for CO2 fixation and conversion, offering a renewable and efficient method for addressing carbon emissions. Algae, with its high growth rate and lipid contents, exhibits CO2 fixation capabilities during photosynthesis. Similarly, methanogens have shown efficiency in converting CO2 to methane by methanogenesis, offering a viable pathway for carbon sequestration and energy production. In conclusion, our study highlights the importance of exploring biological pathways, which significantly reduce carbon emissions and move towards a more environmentally friendly future. The output of this review highlights the significant potential of CCSU models for future sustainability. Furthermore, this review has been intensified in the current agenda for reduction of CO2 at considerable extends with biofuel upgrading by the microbial-shift reaction.
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Dióxido de Carbono , Sequestro de Carbono , Mudança Climática , Biocombustíveis , Carbono , Aquecimento GlobalRESUMO
Life-cycle assessment (LCA) is one of the most widely applied methods for sustainability assessment. A main application of LCA is to compare alternative products to identify and promote those that are more environmentally friendly. Such comparative LCA studies often rest on, explicitly or implicitly, an idealized assumption, namely, 1:1 displacement between functionally equivalent products. However, product displacement in the real world is much more complicated, affected by various factors such as the rebound effect and policy schemes. Here, we quantitatively review studies that have considered these aspects to evaluate the magnitude and distribution of realistic displacement estimates across several major product categories (biofuels, electricity, electric vehicles, and recycled products). Results show that displacement ratios concentrate around 40-60%, suggesting considerable overestimation of the benefits of alternative products if the 1:1 displacement assumption was used. Overall, there have been a small number of modeling studies on realistic product displacement and their scopes were limited. Additional research is needed to cover more product categories and geographies and improve the modeling of market and policy complexities. As such research accumulates, their displacement estimates can form a database that can be drawn upon by comparative LCA studies to more accurately determine the environmental impacts of alternative products.
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Reciclagem , Biocombustíveis , Modelos Teóricos , Meio AmbienteRESUMO
There is growing scientific interest in oleaginous yeasts producing microbial oils as precursors of biofuels and potential substitutes for fossil fuels. Due to the high cost of substrates commonly metabolized by yeasts, volatile fatty acids (VFAs) are gaining interest as alternative cheap and sustainable carbon sources, which can be obtained from solid, liquid and gas pollutants. In this research, Rhodosporidium toruloides was proven to be able to accumulate microbial oils from VFAs obtained from the fermentation of syngas by Clostridium carboxidivorans. Using CO2 and CO as carbon sources from the syngas mixture and H2 as energy source, this acetogen produced, via the Wood-Ljungdahl pathway, a mixture of acetic, butyric and caproic acids. It was first revealed that R. toruloides exhibited minimal inhibition at concentrations below 12 g/L when exposed to a mixture of VFAs, which included acetic, butyric and even hexanoic acids. The yeast was then grown on the culture medium derived from the acetogenic fermentation of syngas. Between the two yeast strains tested of the same species, R. toruloides DSM 4444 reached a total VFAs consumption of 69.1 g/L, supplied by successive additions of acids to the reactor, yielding a maximum lipid content of 29.7% w/w cell. The lipid profile obtained in this case, in terms of abundance followed the order C18:1 > C16:0 ≥ C18:0 > C18:2>others; in which the dominant compound (C18:1), represented approximately 50% of the total. This research opens new possibilities in the cultivation of oleaginous yeasts for the production of biofuels and bioproducts from C1 gases.
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Biocombustíveis , Dióxido de Carbono , Clostridium , Ácidos Graxos Voláteis , Fermentação , Dióxido de Carbono/metabolismo , Dióxido de Carbono/análise , Clostridium/metabolismo , Ácidos Graxos Voláteis/metabolismo , Rhodotorula/metabolismoRESUMO
Replacing fossil resource with biomass is one of the promising approaches to reduce our carbon footprint. Lignin is one of the three major components of lignocellulosic biomass, accounting for 10-35 wt% of dried weight of the biomass. Hydrogenolytic depolymerization of lignin is attracting increasing attention because of its capacity of utilizing lignin in its uncondensed form and compatibility with the biomass fractionation processes. Lignin is a natural aromatic polymer composed of a variety of monolignols associated with a series of lignin linkage motifs. Hydrogenolysis cleaves various ether bonds in lignin and releases phenolic monomers which can be further upgraded into valuable products, i.e., drugs, terephthalic acid, phenol. This review provides an overview of the state-of-the-art advances of the reagent (lignin), products (hydrol lignin), mass balance, and mechanism of the lignin hydrogenolysis reaction. The chemical structure of lignin is reviewed associated with the free radical coupling of monolignols and the chemical reactions of lignin upon isolation processes. The reactions of lignin linkages upon hydrogenolysis are discussed. The components of hydrol lignin and the selectivity production of phenolic monomers are reviewed. Future challenges on hydrogenolysis of lignin are proposed. This article provides an overview of lignin hydrogenolysis reaction which shows light on the generation of optimized lignin ready for hydrogenolytic depolymerization.
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Hidrogênio , Lignina , Lignina/química , Hidrogênio/química , Polimerização , Biomassa , HidróliseRESUMO
The rapid depletion of conventional fuel resources and rising energy demand has accelerated the search for alternative energy sources. Further, the expanding need to use bioenergy crops for sustainable fuel production has enhanced the competition for agricultural land, raising the "food vs. fuel" competition. Considering this, producing bioenergy crops on marginal land has a great perspective for achieving sustainable bioenergy production and mitigating the negative impacts of climate change. C4 crops are dual-purpose crops with better efficiency to fix atmospheric CO2 and convert solar energy into lignocellulosic biomass. Of these, millets have gained worldwide attention due to their climate resilience and nutraceutical properties. Due to close synteny with contemporary C4 bioenergy crops, millets are being considered a model crop for studying diverse agronomically important traits associated with biomass production. Millets can be cultivated on marginal land with minimum fertilizer inputs and maximum biomass production. In this regard, advanced molecular approaches, including marker-assisted breeding, multi-omics approaches, and gene-editing technologies, can be employed to genetically engineer these crops for enhanced biofuel production efficiency. The current study aims to provide an overview of millets as a sustainable bioenergy source and underlines the significance of millets as a C4 model to elucidate the genes and pathways involved in lignocellulosic biomass production using advanced molecular biology approaches.
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Biocombustíveis , Biomassa , Produtos Agrícolas , Milhetes , Produtos Agrícolas/crescimento & desenvolvimento , Produtos Agrícolas/metabolismo , Produtos Agrícolas/genética , Milhetes/genética , Milhetes/metabolismo , Lignina/metabolismoRESUMO
The genus Eutreptiella (Euglenophyceae/Euglenozoa) comprises unicellular organisms known for their photosynthetic capacity and significant role in marine ecosystems. This review highlights the taxonomic, ecological, and biotechnological characteristics of Eutreptiella species, emphasizing their morphological and genomic adaptations. Eutreptiella species exhibit high phenotypic plasticity, enabling adaptation to various environmental conditions, from nutrient-rich waters to high-salinity conditions. They play a crucial role in primary production and nutrient cycling in marine ecosystems. Genetic and transcriptomic studies have revealed their complex regulatory mechanisms and potential for biofuel and nutraceutical production. Eutreptiella blooms significantly impact local ecosystems, influencing nutrient availability and community dynamics. Additionally, interactions with associated bacteria enhance their growth and metabolic capabilities. The genus shows substantial genetic variability, suggesting potential misidentifications or a polyphyletic nature. Further comprehensive studies are needed to clarify their taxonomy and evolutionary relationships. Understanding and managing Eutreptiella populations is essential to leverage their biotechnological potential and ensure the health of marine ecosystems.
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The rhizosphere, the soil region influenced by plant roots, represents a dynamic microenvironment where intricate interactions between plants and microorganisms shape soil health, nutrient cycling, and plant growth. Soil microorganisms are integral players in the transformation of materials, the dynamics of energy flows, and the intricate cycles of biogeochemistry. Considerable research has been dedicated to investigating the abundance, diversity, and intricacies of interactions among different microbes, as well as the relationships between plants and microbes present in the rhizosphere. Metagenomics, a powerful suite of techniques, has emerged as a transformative tool for dissecting the genetic repertoire of complex microbial communities inhabiting the rhizosphere. The review systematically navigates through various metagenomic approaches, ranging from shotgun metagenomics, enabling unbiased analysis of entire microbial genomes, to targeted sequencing of the 16S rRNA gene for taxonomic profiling. Each approach's strengths and limitations are critically evaluated, providing researchers with a nuanced understanding of their applicability in different research contexts. A central focus of the review lies in the practical applications of rhizosphere metagenomics in various fields including agriculture. By decoding the genomic content of rhizospheric microbes, researchers gain insights into their functional roles in nutrient acquisition, disease suppression, and overall plant health. The review also addresses the broader implications of metagenomic studies in advancing our understanding of microbial diversity and community dynamics in the rhizosphere. It serves as a comprehensive guide for researchers, agronomists, and policymakers, offering a roadmap for harnessing metagenomic approaches to unlock the full potential of the rhizosphere microbiome in promoting sustainable agriculture.
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Sweet sorghum can be used to produce a substantial quantity of biofuel due to its high biological yield and high carbohydrate content. In this study, we investigated the dynamic changes in fermentation characteristics, carbohydrate components, and the bacterial community during the ensiling of wilted and unwilted sweet sorghum. The results revealed a rapid fermentation pattern and high-quality fermentation quality in wilted and unwilted sweet sorghum, wherein lactic acid, and acetic acid accumulated and stabilized during the initial 9 days of ensiling, with the pH values less than 4.2, until 60 days of ensiling. We found that the ensiling of sweet sorghum involved the degradation (5% ~ 10%) of neutral detergent fiber (NDF) and hemicellulose and that the degradation of NDF fit a first-order exponential decay model. A shift in dominance from Lactococcus to Lactobacillus occurred before the first 9 days of ensiling, and the abundance of Lactobacillus (r = -0.68, p < 0.001) was negatively correlated with the NDF content. The relative abundances of Lactobacillus in wilted and unwilted sweet sorghum after ensiling for 60 days were 76.30 and 93.49%, respectively, and relatively high fermentation quality was obtained. In summary, ensiling is proposed as a biological pretreatment for sweet sorghum for subsequent biofuel production, and unlike other materials, sweet sorghum quickly achieves good fermentation quality and has great potential for bioresource production.