Bioresource technology • 2026

In this work, the inhibition of microplastics (MPs, 50 μm) and nanoplastics (NPs, 50 nm) on denitrification at biocathode in bioelectrochemical system (BES), and the alleviated of this inhibition on nitrogen metabolism using algal biochar (ABC) were investigated. With the addition of biochar, it was found that nitrate removal increased to 75.6 % in the NP-50-ABC group, significantly higher than the 51.2 % observed in the NP-50 group. First, biochar was found to mitigate oxidative stress by reducing reactive oxygen species (ROS) and lactate dehydrogenase (LDH) release, while maintaining extracellular polymer secretion and cell membrane integrity. Second, ABC also helped reshape microbial communities, enrich denitrifying bacteria, and enhance the abundance of key functional genes (napA, napB, norB, nosZ) and enzymes. Third, biochar stimulated pathways for the anabolic reduction of nitrate to ammonia, thereby synergistically removing nitrate through denitrification. These findings provide theoretical support for improving BES resilience against emerging pollutants.

Food research international (Ottawa, Ont.) • 2026

Fermented alcoholic beverages are globally cherished for their diverse sensory profiles, shaped by complex microbial metabolism. Environmentally-driven microbial interactions play a significant role in regulating the synthesis of flavor metabolites. However, mechanisms linking environmental factors to microbial interactions and flavor formation are unclear, hindering the optimization of fermented alcoholic beverages. This work systematically discussed regulatory mechanisms by which microbial interactions govern flavor formation in environment-driven polymicrobial fermentation processes of alcoholic beverages. By integrating representative global fermented alcoholic beverages (e.g., Baijiu, Pulque, and grape wine), we elucidated the framework of Environmental factors-Microbial interactions-Flavor regulation, a dynamic coupling framework. This framework indicated that environmental factors drove microbial interactions, which in turn regulated flavor metabolism. Concurrently, flavor metabolites provided feedback to reshape the microenvironment, thereby forming a closed framework. Key findings were concluded: (i) environmental gradients (e.g., in temperature, oxygen, pH) shaped microbial interaction by modulating thermodynamic, electrochemical, and kinetic equilibria; (ii) these interactions directly orchestrated flavor metabolome assembly, where synergy enhanced target esters (e.g., ethyl hexanoate), competition balanced diversity, and antagonism suppressed off-flavors; (iii) flavor metabolites, in turn, provided feedback by chemically and physically reshaping the microenvironment (e.g., via acidification and ethanol-driven anaerobiosis); and (iv) cross-scale methodologies (multi-omics, computational modeling, IoT sensing) enabled deciphering the framework from cellular to community levels. The framework establishes a foundation for designing synthetic microbial consortia, enhancing starter culture robustness for stable flavor production, and guiding targeted flavor optimization.

Biotechnology advances • 2026

The persistence of toxic heavy metals in aquatic and terrestrial environments poses long-term risks to ecosystems and human health. Microbial bio-reductive immobilization driven by Extracellular Electron Transfer (EET) has emerged as a promising and environmentally sustainable remediation strategy. This review synthesizes recent advances in EET-driven bio-reduction of major heavy metals and critically evaluates enhancement strategies designed to overcome intrinsic limitations in electron transfer efficiency. Particular attention is given to engineering-oriented approaches, including conductive minerals and materials, exogenous electron shuttles, electrochemical and photochemical stimulation. Key findings highlight that rational EET enhancement can markedly improve bio-reduction efficiency of heavy metals. Future perspectives are discussed with a focus on green materials, bio-electrochemical system integration, genetic and community-level regulation, and scale-up considerations. Remaining challenges include material sustainability, genetic biosafety concerns, scalability and operational robustness. Overall, this review distills design-oriented insights that bridge EET-driven mechanisms with enhancement strategies toward robust and scalable heavy metal immobilization.

Journal of hazardous materials • 2026

Landfill leachate bio-treated effluent (LLBE) is characterized by high levels of chloride ions and complex organic pollutants with poor biodegradability. The use of electrochemical oxidation (EO) to the water sample can enhance its biodegradability. However, the generation of chlorinated disinfection by-products (Cl-DBPs) and residual free available chlorine (FAC) can pose risks to subsequent biological treatment processes. This study aims to propose a method based on H 2 O 2 regulation to convert the reactive species in the EO system from a FAC-dominated regime to a 1 O 2 -contributing regime, inhibiting the production of Cl-DBPs and eliminating FAC residues. After treatment by the EO system, the BOD 5 /COD ratio of the water sample increased from 0.15 to 0.49. Under the regulation of H 2 O 2 , the concentration of Cl-DBPs in the effluent of the EO system diminished from 14.02 mg/L to 2.88 mg/L, while the inhibition rate of luminous bacteria reduced from 95.97 % to 19.80 %. Moreover, sludge derived from the effluent of the EO system treated with H 2 O 2 exhibited superior performance and microbial community structure compared to sludge obtained from the original EO system effluent. It is proposed that H 2 O 2 undergoes a series of reactions within the EO system: electron transfer occurs at the electrode surface, generating free radicals such as HO 2 · and O 2 ·- . Free radical chain reactions and the rapid chemical reactions between H 2 O 2 and FAC are the two pathways through which 1 O 2 is produced. It indicated that EO treatment improved the biodegradability and the addition of H 2 O 2 reduced the biological toxicity of the effluent.

Water research • 2026

Anaerobic fermentation of waste activated sludge (WAS) into short-chain fatty acids (SCFAs) is a promising valorization strategy, yet it is often constrained by inefficient hydrolysis and the presence of contaminants. This study reports a synergistic electrochemical activation coupling a boron-doped diamond anode (BDD) with peroxymonosulfate (PMS), i.e., B/P, which enhances SCFA production and pollutant degradation. The integrated B/P system achieved a maximal SCFA yield, which was 2.0-fold higher than the control and significantly surpassed mono-pretreatments (BDD, PMS) and their sequential combination (B + P). Furthermore, it optimized product composition, increasing the proportion of high-value acetic acid by 2.7-fold. Mechanistic investigations revealed that the electrochemical synergy generated reactive species (e.g., •OH, SO 4 •⁻, 1 O 2 ), which profoundly accelerated sludge solubilization (supported by 10.7 times of SCOD produced by B/P relative to the sum of SCOD by mono-BDD and mono-PMS). Microbial analysis demonstrated that B/P pretreatment restructured the community to enrich key hydrolytic and acidogenic phyla. This was corroborated by the upregulation of genes associated with carbohydrate hydrolysis and acidogenesis, alongside the suppression of methanogenesis. Beyond SCFA enhancement, the B/P system also improved sludge dewaterability (24 % reduction in capillary suction time), efficient removal of sulfamethoxazole (62.7 %), and substantially transferred heavy metals from the sludge solids into the liquid phase (e.g., 71.8 % of total Cu was transferred from the solid phase to the supernatant). These findings highlight the B/P process as a multifunctional pretreatment for efficient sludge bioconversion, pollutant removal, and environmental risk mitigation.

Angewandte Chemie (International ed. in English) • 2026

Selective C-H functionalization remains a central challenge in modern synthesis as it enables direct diversification of molecular scaffolds without pre-functionalization. Peroxygenases, including both unspecific peroxygenases and P450 peroxygenases, offer a biocatalytic solution to this challenge, catalyzing oxyfunctionalization reactions in aqueous media under mild conditions with hydrogen peroxide (H 2 O 2 ) as the sole oxidant. In this review, we highlight recent advances in peroxygenase engineering over the past five years, with a particular focus on strategies that enhance heterologous expression, catalytic activity, and control of regio- and enantioselectivity. We also discuss protein engineering approaches that mitigate H 2 O 2 -induced inactivation and summarize efforts to repurpose NADPH-dependent P450 enzymes into self-sufficient peroxygenases, thereby expanding their catalytic repertoire. Furthermore, we examine the integration of peroxygenases with in situ H 2 O 2 generation systems by enzymatic, chemical, photocatalytic, and electrochemical methods to achieve balanced oxidant delivery and sustained turnover. Collectively, these developments have established peroxygenases as versatile and robust catalysts for selective C-H functionalization, opening new opportunities for their application in the synthesis of pharmaceuticals, fine chemicals, and agrochemicals.

Research (Washington, D.C.) • 2026

The poultry industry faces major challenges in preserving meat freshness and safety due to high water activity, rapid microbial growth, and oxidative spoilage. Traditional methods such as vacuum sealing and antioxidants are insufficient, as they cannot effectively suppress anaerobic pathogens and lack real-time freshness assessment. This review introduces a transformative strategy that applies coordination chemistry to design multifunctional nanomaterials for poultry preservation. Dynamic metal-ligand interactions-including redox-active centers, stimuli-responsive bonds, and host-guest adsorption-allow precise antibacterial control through 4 mechanisms: ligand-regulated ion release, reactive oxygen species (ROS) generation, coordination-triggered antimicrobial delivery, and electrostatic membrane disruption. In addition, freshness can be monitored by biomarker-specific coordination responses, such as nanoparticle aggregation for optical signals or MOF (metal-organic framework)-based volatile amine capture for colorimetric and electrochemical detection. Integration with oxygen scavengers, humidity regulators, and pH-responsive systems optimizes the packaging environment. Coupling with digital technologies further enables intelligent platforms for autonomous quality validation and supply chain transparency. This approach connects molecular-scale coordination principles with engineering practice while addressing biodegradability, environmental resilience, and scalability to reduce waste and achieve sustainable poultry preservation.

Environmental research • 2026

Frequently abrupt temperature shifts driven by global climate change significantly disrupt carbon sequestration and CO 2 emissions in wetland ecosystems. The condition has raised an important question to clarify ambiguity in the regulatory mechanism of greenhouse gas (GHG) emissions from some of the world's ecologically important large river floodplain wetland systems. This study investigated how abrupt temperature changes could modulate GHG emissions from surface sediments of the China's Yangtze River floodplain wetlands (YRW). A microcosm experiment was conducted in YRW with four temperature treatments: control (20 °C), abrupt cooling (8 °C), abrupt heating (32 °C), and abrupt heating followed by cooling (32 °C to 8 °C) by simulating the latest daily temperature fluctuations (≥12 °C) in the region. Dissolved organic matter (DOM) composition was analyzed in each treatment using the three-dimensional fluorescence spectroscopy followed by the measurement of concentrations of dissolved organic carbon (DOC), total carbon (TC), and total nitrogen (TN) using a TOC analyzer. DOM redox properties were then evaluated through mediated electrochemical techniques. Our results showed that the abrupt heating increased CO 2 emissions, while heating followed by cooling suppressed CO 2 emissions but significantly increased CH 4 emissions. These responses were clearly linked to changes in the carbon concentration and DOM composition in YRW. Specifically, the abrupt heating may have enriched microbial-derived fulvic acid and increased DOC levels, enhancing the electron-accepting capacity (EAC) of DOM by 40-60 %. Fluorescence spectroscopy measurement showed a 12-30 % increase in microbial-derived DOM components under heating. These results demonstrate that temperature-induced alterations in the DOM structure and redox reactivity in large river floodplain wetland sediments strongly regulate GHG fluxes of both CO 2 and CH 4 , providing an important insight into carbon cycling and help developing improved wetland management strategies under climatic warming in YRW.

Advanced materials (Deerfield Beach, Fla.) • 2026

Bioelectrochemical systems interconvert electrical and chemical energy using living microorganisms, but their efficiency remains limited by slow electron exchange across abiotic-biotic interfaces. Herein, a spontaneous n-doped water-dispersible conjugated polyelectrolyte (CPE), PNB, is developed. The CPE self-assembles on the surface of Shewanella oneidensis MR-1 to create biocompatible coatings that accelerate inward extracellular electron transfer. PNB is obtained via an aldol condensation reaction and is described by an acceptor-acceptor π-conjugated backbone bearing quaternary ammonium side chains. This molecular architecture enables stable n-doping in aqueous media and a broad reduction potential window. When integrated as a cathodic interlayer, PNB-S. oneidensis biohybrids exhibit a 14-fold enhancement in electron injection and a 4-fold increase in electro-driven succinate production, compared to unmodified cells. Single-cell electrochemical mapping confirms faster, more efficient per-cell electron influx. These findings demonstrate that n-type CPEs can bridge external electrodes with cellular metabolisms, opening a material-based route to high-performance bioelectronic and electrosynthetic systems. By enabling more facile charge transfer between synthetic semiconductors and living catalysts, this work establishes a soft materials-driven framework for designing electronically coupled microbial systems with potential to advance sustainable bioelectronic technologies.

Biosensors • 2026

Quantifying microbial growth with high temporal resolution remains essential yet challenging due to limitations of optical, manual, and biochemical methods. Here, we introduce an AI-enhanced electrochemical impedance spectroscopy platform for real-time, label-free monitoring of Saccharomyces cerevisiae growth. Broadband impedance measurements (1 Hz-100 kHz) were collected from yeast cultures across log-phase development. Engineered features-derived from impedance magnitude and phase-captured dielectric and conductive shifts associated with cell proliferation, membrane polarization, and ionic redistribution. A Gaussian Process Regression model trained on these features predicted optical density (OD600) with high precision (RMSE = 0.79 min; R 2 = 0.9996; r = 0.9998), and achieved 100% classification accuracy when discretized into 15-min growth intervals. The system operated with sub-millisecond latency and minimal memory footprint, enabling embedded deployment. Benchmarking against conventional methods revealed superior throughput, automation potential, and independence from labeling or turbidity-based optics. This AI-driven platform forms the core of a real-time digital twin for yeast culture monitoring, capable of predictive tracking and adaptive control. By fusing electrochemical biosensing with machine learning, our method offers a scalable and robust solution for intelligent fermentation and bioprocess optimization.

Food research international (Ottawa, Ont.) • 2026

The widespread presence of pathogenic microorganisms in food and environmental sources poses a persistent threat to public health. Conventional detection methods-including culture, microscopy, and biochemical assays-are limited by low sensitivity, cross-reactivity, and prolonged turnaround times, particularly when microbial loads are low or phenotypic overlap occurs. These limitations underscore the urgent need for diagnostic platforms that combine speed, specificity, and sensitivity. The advent of CRISPR/Cas (Clustered Regularly Interspaced Short Palindromic Repeats/CRISPR-associated) systems has revolutionized microbial diagnostics, driving the emergence of electrochemical CRISPR/Cas (EC-CRISPR/Cas) biosensors. This review surveys four principal electrochemical CRISPR/Cas (EC-CRISPR/Cas) platforms-Cas9, Cas12a, Cas13a, and Cas14a-emphasizing their structural characteristics, biosensing mechanisms, and signal amplification strategies for both nucleic acid and non-nucleic acid pathogen detection. We first outline the molecular architecture and functional mechanisms of each Cas protein in the context of biosensing. EC-CRISPR/Cas detection strategies are classified as nucleic acid-based (either amplification-free or amplification-dependent) or non-nucleic acid-based, the latter primarily relying on aptamer-mediated recognition. We also provide a comparative analysis of signal enhancement techniques and application scenarios across bacterial, viral, fungal, and parasitic pathogens. Importantly, we identify key limitations of current systems-such as poor reusability, signal drift, and challenges in point-of-care deployment-and present emerging solutions including crRNA engineering, nanomaterial integration, and artificial intelligence-guided biosensor design. These innovations hold strong potential to enhance sensitivity, specificity, and real-time performance, offering a foundation for next-generation, scalable EC-CRISPR/Cas diagnostics.

Current opinion in biotechnology • 2026

Microbes regulate their dynamic behaviors using the chemical and physical characteristics of their environment. The ability of microbes to continuously convert this physicochemical information into biochemical information and to use organic matter in the environment as a power source makes these organisms attractive as chassis for building sensors. However, most biosensors have severe limitations when considering applications in hard-to-image settings like soils, sediments, and wastewater. Emerging technologies at the interface of biomolecular design, microbiome engineering, and synthetic biology offer new tools to program cells and communities as biosensors for these settings. In this review, we describe innovations in biosensor outputs that are enabling new applications in complex environments, including reporters that are read out using electrochemical, gas chromatography, hyperspectral imaging, and next-generation sequencing methods. We also discuss computational advances that are accelerating the diversification of sensing components by mining metagenomics data for new transcriptional regulators and by designing allosteric protein switches that directly regulate reporter outputs using analytes. We highlight emerging opportunities for programming undomesticated microbes in communities to function as distributed sensors in the environment. Finally, we discuss the need for responsible biosensor development and to modernize regulatory frameworks to support evidence-based assessment of environmental biosensors.

Journal of microbiological methods • 2026

Pharmaceutical water is a crucial component in drug manufacturing, as its quality directly affects drug safety and efficacy. This study focuses on membrane biofouling in pharmaceutical water systems during downtime, revealing its unique formation mechanisms: abrupt decreases in flow rate, reduced dissolved oxygen, and nutrient accumulation collectively create favourable conditions for microbial colonization. Biofilm formation not only causes a decline in membrane flux and an increase in transmembrane pressure but may also release harmful substances, such as endotoxins, posing a severe threat to water quality. The study systematically reviews existing control technologies, encompassing conventional methods such as chemical cleaning and backflushing, as well as innovative approaches including electrochemical treatment and cold atmospheric pressure plasma (CAP) technology. Furthermore, this paper prospectively explores future research directions, such as the development of green antifouling agents and the application of intelligent monitoring technologies, providing a scientific basis and technical support for achieving water safety and sustainable development in the pharmaceutical industry.

Water research • 2026

Nanoscale zero-valent iron (nZVI) serves as an effective electron donor to enhance anaerobic methanogenesis, yet its high reducibility often induces microbial nanotoxicity, creating a fundamental conflict between reactivity and biocompatibility. Herein, we synthesized an extracellular polymeric substance (EPS)-modified nZVI bio-composite (nZVI@EPS) via one-step liquid-phase reduction, with a focus on the structural characteristics and functional interplay of its core-shell architecture in bio-nano systems. We found that EPS decelerated precursor reduction kinetics, suppressing supersaturation-induced crystallization and favoring the formation of an amorphous iron core with elongated Fe-Fe bonds that enhanced its thermodynamic driving force for electron donation. Simultaneously, the resulting EPS layer served as a biocompatible and pseudocapacitive biointerface, physically shielding microorganisms from direct contact and electrochemically buffering electron surge from the highly reductive iron core through a storage and controlled-release mechanism. Hydrogen evolution experiments confirmed that the amorphous core ensured sufficient electron supply, while the EPS biointerface merely regulated the electron release kinetics without sacrificing ultimate utilization efficiency. In the anaerobic digestion of waste activated sludge, the optimized core-interface synergistically enhanced methane yield and biogas purity by 31.11 % and 37.42 %, respectively. Such improvements were underpinned by enhanced enzymatic activities, reinforced energy conservation, and a redirected methanogenic metabolic flux toward the hydrogenotrophic pathway. This study leverages insights from iron core-interface functional decoupling to propose a synchronized optimization strategy, establishing a universal design framework for engineering nZVI materials that integrate high reactivity with biocompatibility for efficient waste-to-energy conversion.

Talanta • 2026

Microplastics and nanoplastics (MNPs) as emerging pollutants present substantial risks to both the environment and human health. Developing highly sensitive methods to rapidly identify and detect low concentrations of MNPs in complex systems remains a considerable challenge. Here, an "off-on" switch-type photoelectrochemical (PEC) aptasensor was employed for the sensitive detection of polyvinyl chloride (PVC) and polystyrene (PS) MNPs. This PEC aptasensor was based on a two-dimensional organic-inorganic Z-scheme heterojunction and utilized an acetylferrocene-modified aptamer (Apt-AcFc) as PEC recognition and quencher probes. In general, combining Apt-AcFc with the photoelectrode efficiently quenches the photocurrent, transitioning it to the 'off' state. Conversely, the presence of MNPs greatly increases the photocurrent because the MNPs were specifically recognized by Apt-AcFc, causing Apt-AcFc detaching from the photoelectrode and transition to the 'on' state. The developed PEC aptasensor was employed for the detection of MNPs released from food packaging materials. Although the aptasensor displayed distinct sensitivities toward PVC and PS, it demonstrated a consistent linear dynamic range of 1-200 μg mL -1 and a low detection limit of 0.1 μg mL -1 . This switching-type PEC aptasensor provides a rapid, sensitive, and reliable analytical platform for the determination of MNPs in food and environmental matrices.

Bioelectrochemistry (Amsterdam, Netherlands) • 2026

A stable nanofluid containing ZnO nanoparticles (ZnO NPs) and a plant-based surfactant, soapnut, was synthesized and its composite nature established by thermogravimetry, Fourier-transform infrared spectroscopy, scanning electron microscopy, and energy dispersive X-ray (EDX) analyses. Its effectiveness as a microbially induced corrosion (MIC) inhibitor was investigated. Gravimetric and electrochemical techniques-potentiodynamic polarisation and electrochemical impedance spectroscopy, revealed a reduction in corrosion rates (from 31.63 to 1.17 mils/year), achieving an inhibition efficiency of up to 97% at a low nanofluid concentration of 4 vol%. Both the components- ZnO NPs and the soapnut extract (SN) exhibited pronounced bactericidal activity, leading to effective suppression of biofilm formation, as confirmed by biofilm inhibition assays (78%) and confocal laser scanning microscopy imaging. The amphiphilic nature of SN, together with the high surface availability of ZnO NPs, enhanced inhibitor adsorption on the metal surface which was supported by adsorption studies and surface analyses- field-emission scanning electron microscopy coupled with EDX. In the synthesized composite, SN acting as a ligand, prevented aggregation of ZnO NPs and thereby improved surface coverage and stability. Overall, the synergistic interaction between SN and ZnO NPs produced an environmentally benign nanofluid with strong potential for mitigating MIC in petrochemical pipeline systems.

Journal of environmental management • 2026

Sulfur autotrophic denitrification (SADN) process is cost-effective and carbon-free for treating nitrate-containing wastewater, but the salt in industrial and municipal (coastal cities) wastewaters typically affects its stability. To address this challenge, an in-depth understanding of the inhibitory mechanisms of salt stress on functional bacteria (denitrifying sulfur-oxidizers) in the SADN process is crucial. By comparing the existing research on the SADN process for saline wastewater treatment, this review identifies the heuristic salinity reference points (i.e., causing irreversible inhibition) of 3.1%-4.8% for the SADN process based on the micro and macro response characteristics. Low salinity levels (0.1%-2.0%) stimulate the SADN process by intensifying the metabolic activity of the salt-tolerant denitrifying sulfur-oxidizers and microbial interactions. In high salinity scenarios, a range of 2.0% to 3.1% or 4.8% (reference points) causes transient inhibition, while salinity exceeding approximate 3.1%-4.8% results in severe inhibition (difficult to recover within a short-term of 8-20 days). High salinity scenario leads to diminished microbial activity, reduced relative abundance of salt-tolerant functional bacteria, and superimposed stress from by-products (nitrite and sulfate), thereby blocking the nitrate removal. Moreover, this review discusses three effective strategies (e.g., addition of exogenous regulators, integration of heterotrophic denitrification, and bio-electrochemical enhancement) for alleviating SADN salt stress and their underlying mitigation mechanisms. Lastly, further research directions on electron transfer response mechanisms and interdisciplinary disinhibition strategies are proposed to broaden the applicability of SADN systems for saline wastewater treatment. This review expands the knowledge of salt inhibitory mechanisms on denitrifying sulfur-oxidizers and provides a theoretical foundation for optimizing SADN systems in saline wastewater treatment.

American journal of physiology. Gastrointestinal and liver physiology • 2026

The intestinal epithelium is a key component of the intestinal barrier, which is the largest and most complex barrier of the human body, regulating nutrients absorption while restricting the entry of harmful antigens. Breakdown of this barrier facilitates microbial and dietary antigenic translocation, triggering local immune system activation and inflammation. Although barrier alterations alone may not be sufficient to initiate disease, accumulating evidence highlights its critical role in the pathogenesis and progression of a wide range of gastrointestinal and systemic disorders. Early identification of intestinal epithelium and barrier alterations could enable timely therapeutic approaches. This systematic review provides an overview of current in vivo (both non-invasive and invasive) and ex vivo/in vitro approaches used to assess intestinal epithelial barrier alterations. Non-invasive in vivo approaches rely mainly on urinary detection of orally ingested probes, but their clinical utility is limited by lack of standardization and specificity. Circulating and fecal constitutive markers derived from the intestinal barrier, which reflect epithelial alterations, together with indicators of microbial translocation, provide complementary insights but remain insufficiently validated. Advanced invasive endoscopic modalities such as confocal laser endomicroscopy enable near-histologic, real-time visualization but are costly and largely used as research tools in specialist centers. In vitro, transepithelial electrical resistance assessment remains the reference standard, though novel technologies (including impedance spectroscopy and organic electrochemical transistors) offer enhanced sensitivity and resolution. Despite progress, major gaps remain, including the absence of a standardized definition of epithelial barrier breakdown, the lack of a practical diagnostic tool, methodological heterogeneity, unvalidated thresholds, and limited prospective validation.

Bioresource technology • 2026

Electric field intensity-driven aerobic composting is an effective method for recovering organic solid waste resources and degrading refractory perfluorooctanoic acid (PFOA). Although electric fields alter the compost microenvironment to overcome natural composting limitations, the mechanism underlying cathode-anode differentiation regulation of microbial metabolic networks to synergistically drive PFOA degradation and humus formation remains unclear. In this study, aerobic composting systems operating at 0, 5, and 10 V were established. High-throughput sequencing and electrochemical analyses were used to test the hypothesis that an exogenous electric field induces spatial redox microenvironment differentiation, guides microbial functional divergence, and enhances synergistic humus synthesis and pollutant removal. The reductive microenvironment of the cathode favored humus synthesis-related genera, facilitating humus accumulation and stabilization through the shikimic acid metabolic pathway. The 10 V treatment significantly increased the humus accumulation (55.61 %) compared with the control. The oxidative microenvironment of the anode specifically enriched denitrifying genera, which facilitated PFOA degradation using highly active intermediates. The anode region under 10 V treatment exhibited the optimal pollutant removal efficiency and a high PFOA removal rate of approximately 98.55 %. In addition, the electric field enhanced microbial synergy, shifted communities from competition to cooperation, and finally formed a "cathode synthesis-anode degradation" synergistic network. This study elucidates the role of "redox microenvironmental differentiation" in regulating microbial community functions in electric field-driven aerobic composting and provides a novel strategy for developing synergistic technologies for organic waste recycling and refractory pollutant removal.

Bioresource technology • 2026

Microbial electrochemical sensors based on electroactive biofilms (EABs) offer a promising approach for real-time biochemical oxygen demand (BOD) monitoring. However, current standardized EAB designs, developed based on studies of acetate-fed systems, feature a double-layer biofilm architecture with Geobacter anodireducens as the inner core, which oversimplifies microbial metabolism in fermentable wastewater and often leads to underestimated BOD values. In natural EABs cultured with domestic wastewater, we revealed a specific, selective metabolic cooperation between Geobacter and fermentative microorganisms, where different fermentative taxa preferentially associated with electroactive or methanogenic partners. Using glucose-fed EABs, Dysgonomonas termitidis was identified within the inner layer as a representative fermentative partner exhibiting strong synergy with Geobacter. Based on this, a layered "sandwich-like" EAB (S-EAB) was constructed, sequentially comprising G. anodireducens, pre-enriched D. termitidis and self-adapted environmental microorganisms. Incorporating this intermediate functional layer improved BOD sensing accuracy for glucose by 28%, with results closely matching theoretical values. This study demonstrates that integrating a selectively cooperative fermentative partner within the middle biofilm layer provides a practical strategy for designing high-performance EABs tailored to fermentable wastewater.

Journal of hazardous materials • 2026

Bioelectrochemical systems (BESs) offer promising solutions for remediating halogenated organic pollutants (HOPs) in soil-water matrices. However, their practical efficiency is often constrained by inefficient "last nanometer" electron transfer from electrodes to reductive dehalogenases. Current understanding remains limited by reliance on functional resolution of microbial communities at the strain level, and insufficient understanding of electron flux allocation among competing metabolic pathways. This review introduces a conceptual framework of "Microbial Electrochemical Synergy", which systematically deciphers BESs performance through three dimensions: electron flow efficiency, functional microbial niche partitioning, and interfacial microenvironment characteristics. We revealed that: (1) the electrode-biofilm interface represents a critical rate-limiting step; (2) electron flux diversion to competing pathways (e.g., methanogenesis) significantly affects dehalogenation efficiency; and (3) interfacial microenvironment engineering holds untapped potential for enhancing microbial synergy and electron transfer. The unique value of this review lies in proposing an integrative mechanistic framework that synergizes machine learning, multi-omics, and synthetic biology tools to enable rational design and precise regulation of next-generation BES technologies. By bridging fundamental mechanisms with practical applications, this work aims to enhance the scalability and sustainability of BES-based strategies for enhanced HOPs remediation in complex soil-water matrices.

Journal of nanobiotechnology • 2026

Bacterial biofilms employ complex electrochemical communication networks, primarily mediated through extracellular electron transfer (EET) and ion channel-dependent signaling, to coordinate metabolic activities and collective behaviors. Recent advances in nanotechnology have unveiled the potential of nanomaterials as novel modulators of these electrochemical networks. This review systematically examines the mechanisms by which nanomaterials modulate electrochemical communication in biofilms, with a particular focus on two principal pathways: (1) redox-driven electron transfer and (2) ion channel-mediated signal transduction. In addition, this article also summarizes the applications of biofilm electrochemistry, from energy harvesting, anti-biofilm therapeutics, agricultural practices, to synthetic biological systems, thereby underscoring the translational potential of nanomaterial-mediated electrochemical regulation. Finally, this review analyzes the key factors influencing these interactions, including the physicochemical properties of nanomaterials (composition, surface charge, size, etc.), the heterogeneity of biofilm architecture (e.g., bacterial species), and environmental variables (pH, temperature, light, etc.). Emerging evidence suggests that nanomaterials can program multispecies biofilm architectures and enable dynamic modulation of microbial communities by manipulating interspecies electrochemical dialogues. Nonetheless, critical challenges remain, such as the identification of key molecular players, the elucidation of dynamic regulatory mechanisms, and the optimization of nanomaterial properties. Future directions highlight the decoding of electrochemical signaling codes, deeper insights into host-microbe electrochemical dialogues, and the use of biofilm "electro-intelligence" to develop next-generation biotechnologies. Overall, this review provides new perspectives for advancing research on electrochemical communication in biofilms and its sustainable applications in health, energy, and the environment.

[object Object], [object Object], [object Object]

PLOS One • 2026

Stem cells maintain tissue integrity through a balance of self-renewal, differentiation, and loss of function due to aging or stress. Recent studies demonstrate that the stem cell hierarchy is not fixed. Transit-amplifying or terminally differentiated cells can dedifferentiate back into stem-like states. Such plasticity supports regeneration but, when combined with damage accumulation, may also accelerate aging and increase cancer risk. Motivated by these findings, we develop a damage-structured PDE model of a two-compartment lineage consisting of stem and terminally differentiated cells. The model incorporates dedifferentiation, together with a nonlocal δ -function kernel partitioning scheme that conserves total damage and encodes biologically motivated asymmetries. Methodologically, we emphasize reproducibility and robustness on three fronts. First, the δ -kernel partitioning prevents the unbounded drift that arises in local models while preserving conservation. Second, a conservative finite-volume discretization with upwind fluxes and verified first-order accuracy ensures stability and exact mass balance, as confirmed by manufactured-solution tests. Third, distributional metrics and systematic parameter sweeps provide reproducible ways to quantify lineage-level damage dynamics under varying dedifferentiation and repair conditions. These analyses show that threshold-dependent and repair-modulated dedifferentiation both act as protective mechanisms: the former functions as a ‘detoxification loop’ that recycles high-damage cells, and the latter reduces the damage burden imported during dedifferentiation. Together, they mitigate aging-inducing effects. Parameter sweeps further delineate when dedifferentiation stabilizes tissue maintenance versus when it drives aging-like dynamics. Overall, our reproducible framework integrates biological insights on stem-cell plasticity and damage segregation with rigorous mathematical modeling, providing a foundation for experimental validation and therapeutic strategies targeting stem-cell aging and cancer initiation.

[object Object], [object Object], [object Object] et al.

bioRxiv (Cold Spring Harbor Laboratory) • 2026

Genetic diversity within sexually reproducing species arises via the formation and repair of programmed DNA double-strand breaks (DSBs) created by the evolutionarily conserved topoisomerase-like enzyme, Spo11. Because DSBs threaten genome stability, their formation is tightly regulated in both space and time. In S. cerevisiae, Tel1, the orthologue of mammalian Ataxia Telangiectasia Mutated (ATM) kinase, suppresses nearby DSB formation through local inhibition known as DSB interference. However, whether such local inhibition reshapes the genome-wide DSB landscape remains unclear. Here, we develop a quantitative simulation framework to model how Tel1-mediated feedback shapes Spo11-DSB formation across the yeast genome. We demonstrate that innate chromosome-specific DSB patterns, when combined with interference, generate complex, population-level redistribution of DSBs. We define the spatial range over which interference propagates and provide evidence that this regulatory mechanism requires Tel1 recruitment to DSBs via Xrs2 and Tel1 kinase activity. Although the pro-DSB factor Rec114 contributes to DSB regulation, mutation of potential Rec114 phosphorylation sites indicates that it is not an essential target of Tel1. Together, these findings demonstrate how localised negative feedback can drive broad-scale, emergent patterning of a fundamental genome-modifying process, with the potential in meiosis to influence recombination initiation and, consequently, genetic variation across generations.

Bioresource technology • 2025

Microbial electrolysis cells (MECs) face challenges in hexavalent uranium (U(VI)) remediation due to inefficient extracellular electron transfer (EET), slow biofilm formation, and uranium toxicity. This study developed a cobalt nanoparticles and nitrogen-co-doped carbon (CoNPs/NC) modified biocathode to address these limitations. Material characterization, electrochemical analysis, and density functional theory (DFT) calculations demonstrate that CoNPs/NC enhances biocathode conductivity and promotes EET efficiency while alleviating the toxic inhibition of uranium on microorganisms. The confinement effect facilitates electron delocalization, accelerating electron transfer to adsorbed uranyl ions (UO 2 2+ ) and driving U(VI) to tetravalent uranium (U(IV)) reduction. By optimizing electrode-microbe interactions, CoNPs/NC improves biofilm stability and uranium recovery efficiency. This work provides a novel strategy to synchronize uranium detoxification with sustainable resource recovery in contaminated water systems through nanomaterial-driven electron transfer enhancement.

Water research • 2025

This study investigated the potential of bioelectrochemical systems (BESs) in enhancing arsenic (As) sequestration in sulfur-rich sediments through submerged aquatic plant Vallisneria natans (V. natans). A mechanism entailing bioelectrogenesis-driven sulfur oxidation, which facilitated root iron plaque (IP) formation and As oxidation, was proposed. A 125-day microcosm study was conducted using coupled plant-BES configurations, comprising: a microbial fuel cell (MFC), microbial electrolysis cells (MECs) with voltage gradients, and V. natans. Results showed that As accumulation and enrichment efficiency in IPs increased proportionally with applied voltage. Electrogenesis enhanced IP development, with MECs outperforming the MFC. Rhizospheric phosphorus deficiency in MFC stimulated radial oxygen loss (ROL) and microbial Fe 2+ oxidation for IP formation. In MECs, enhanced endogenous Fe 2+ availability and reduction in ΣH 2 S concentrations collectively facilitated IP development. As oxidation in MFC was significantly amplified within the rhizosphere by As-oxidizing microorganisms. Sulfite (SO 3 2- ), a metabolite of sulfur oxidation, was electrochemically activated in MECs to generate sulfite radicals (SO 3 •- ), demonstrating superior As oxidation efficacy compared to MFC. Metagenomic analysis revealed extracellular electron transfer (EET) efficiency dictated the sulfur oxidation pathway. MFC exhibited FeS 2 -dominated oxidation with terminal S 0 and intermediate S 2 O 3 2- formation, suppressing ΣH 2 S elimination. MECs displayed insufficient EET, driving ΣH 2 S oxidation, FeS consumption, and SO 3 2- accumulation. Intracellular sulfur oxidation pathways differed between systems: the rDsr pathway dominated in MFC, while Hdr process prevailed in MECs. Anode-associated keystone genera responsible for sulfur oxidation were Thiobacillus and Pseudomonas in MFC and MECs, respectively. Iron-oxidizing Collimonas and As oxidizing Halomonas/Acinetobacter were crucial for mediating IP formation and As oxidization, respectively in MFC. These findings demonstrate that BESs are effective tools for augmenting As sequestration by submerged aquatic plants. This investigation establishes foundational insights for practical implementation of integrated plant-BESs in As-contaminated sediment remediation strategies.

Bioelectrochemistry (Amsterdam, Netherlands) • 2025

Bioelectrochemical systems enable the recovery of ammonium from wastewater with low energy requirements and as a concentrated nitrogen-rich stream. This work aims to thoroughly investigate different cathodic electrode configurations and to optimize the operational conditions for active ammonium recovery from synthetic wastewater as concentrated ammonium sulphate. Different applied current intensities (50 mA, corresponding to 5 A m -2 , and 75 mA, corresponding to 7.5 A m -2 ) and initial ammonium concentrations (between 0.3 and 3 g L -1  N-NH 4 + ) were tested in an abiotic electrochemical system to understand the upper threshold of the used three-chamber configuration with hydrophobic membrane in terms of ammonium recovery rate (R rec ). With an external current of 75 mA, the highest value was 55 gN-NH 4 + m -2 d -1 when removing 97 % from an initial ammonium concentration of 3 g L -1 . Bioelectrochemical ammonium removal/recovery was evaluated under different applied potentials (0.8, 1.0, 1.2, and 1.4 V) using two configurations: a Nickel-based gas diffusion electrode (GDE) and a configuration with the cathode (stainless steel or nickel foam) physically separated from the hydrophobic membrane. The highest removal rate (R rem ) (21 gN-NH 4 + m -2 d -1 ) was exhibited for stainless steel cathode at 1.4 V mainly due to its higher current density, which increased the cations migration. This higher R rem also led to a higher R rec (17 gN-NH 4 + m -2 d -1 ).

Nano-micro letters • 2025

Designing high-performance electrocatalysts is one of the key challenges in the development of microbial electrochemical hydrogen production. Transition metal-based (TM-based) electrocatalysts are introduced as an astonishing alternative for future catalysts by addressing several disadvantages, like the high cost and low performance of noble metal and metal-free electrocatalysts, respectively. In this critical review, a comprehensive analysis of the major development of all families of TM-based catalysts from the beginning development of microbial electrolysis cells in the last 15 years is presented. Importantly, pivotal design parameters such as selecting efficient synthesis methods based on the type of material, main criteria during each synthesizing method, and the pros and cons of various procedures are highlighted and compared. Moreover, procedures for tuning and tailoring the structures, advanced strategies to promote active sites, and the potential for implementing novel unexplored TM-based hybrid structures suggested. Furthermore, consideration for large-scale application of TM-based catalysts for future mass production, including life cycle assessment, cost assessment, economic analysis, and recently pilot-scale studies were highlighted. Of great importance, the potential of utilizing artificial intelligence and advanced computational methods such as active learning, microkinetic modeling, and physics-informed machine learning in designing high-performance electrodes in successful practices was elucidated. Finally, a conceptual framework for future studies and remaining challenges on different aspects of TM-based electrocatalysts in microbial electrolysis cells is proposed.

Bioelectrochemistry (Amsterdam, Netherlands) • 2025

Advancement of bioelectrochemical technology depends on efficient screening and enriching of electroactive microorganisms. Yet, conventional methods based on microbial fuel cells or microbial electrolysis cell operation suffer from prolonged operation or false negative results. We propose an anode potential control strategy-periodic step (PS) polarization-for application in screening and enriching electroactive microorganisms from environmental samples. Using fixed potential mode as a control, the performance of PS polarization was examined regarding the start-up time, cultivation duration of three fed-batch cycles, Coulombic efficiency, microbial community composition, and electrochemical properties of biofilms. Electrolysis cells were inoculated by either soil microorganisms or activated sludge. Results demonstrated that the PS polarization significantly shortened the start-up time and duration of the first three cultivation cycles (7-70 days depending on the inoculum) while achieving higher apparent current density and Coulombic efficiency. Besides, the enriched microbial communities under PS polarization showed a higher relative abundance of known electroactive microorganisms. Together with the lower open circuit potential and charge transfer resistance of the biofilm enriched by PS polarization, we concluded that the PS polarization can mitigate the inefficiencies caused by conventional enrichment methods, avoiding trial and error, and can be a novel methodology for enriching electroactive microorganisms.

Bioelectrochemistry (Amsterdam, Netherlands) • 2025

Microbial electrolysis cell (MEC) is an alternative to conventional sludge treatment process with great energy-recovery potential. However, hydrolysis is considered as a rate-limiting step in MEC. In this study, ozone (O 3 ) pretreatment was successfully applied to disintegrate sludge matrix and accelerate microbial electrolysis. At 100-250 mg·g -1 (O 3 /SS), rapid SCOD increment and SS reduction rates were observed with increased O 3 dosage. Afterwards, the mass transfer from gas to liquid was inhibited and oxidation reactions between O 3 and organics occurred, which resulted in a declining disintegration rate. At favorable dosage of 250 mg·g -1 (O 3 /SS), the degree of disintegration was 17 % and SS reduction reached 44.9 %. A lab-scale MEC experiment was performed by feeding ozonated sludge. Results showed that O 3 pretreatment yielded 8.3-times increment in biogas production rate. In addition, O 3 pretreatment improved the organics removal and bioelectrochemical efficiency during microbial electrolysis, achieving 74.50 % of VSS removal rate and 77.56 % of TCOD removal rate, with gas yield increased by 7.5 times and cathodic hydrogen recovery increased by 7.40 %. The FT-IR spectra indicated negligible difference between influent extracellular biological organic matter (EBOM) and effluent EBOM, which suggested the function of O 3 pretreatment was to accelerate microbial electrolysis reactions due to sludge disintegration. Furthermore, the ozonation pretreatment facilitated the enrichment of exoelectrogens and collaborative bacteria in MEC, collectively enhancing MEC performance. This study provides a theoretical reference for enhanced bioelectrochemical treatment of complex heterogeneous mixture with soluble/insoluble organic matters.

Bioresource technology • 2025

Ammonia nitrogen (NH 4 + -N) and sulfate (SO 4 2 - ) removal by Anaerobic ammonium oxidation (Anammox) and sulfate-reducing bacteria (SRB) was studied in dual-chamber microbial electrolysis cells (MECs). Appropriate anode potential stimulation promoted biofilm formation and enhanced extracellular polymeric substances fluorescence, facilitating electron transfer. The highest NH 4 + -N removal (81.1 %) was achieved at the anode potential of 0.6 V vs. Ag/AgCl after 50 days, coinciding with the increase in electroactive Candidatus_Brocadia from 1.1 % to 27.4 %. Simultaneously, SO 4 2 - removal reached 77.0 %, supported by cathodic biofilms dominated by SRB (Desulfofustis, Desulfomicrobium, and Desulfatirhabdium). Automated machine learning and principal co-ordinates analysis identified the anode potential as the key factor shaping microbial ecology. The appropriate anode potential (0.4-0.6 V vs. Ag/AgCl) promoted cathodic sulfidogenesis, indirectly enhancing electron flow and supporting Anammox process at the anode. These findings demonstrate that MECs hold great promise for simultaneously enhancing anaerobic ammonia oxidation bacteria and SRB activities, enabling efficient NH 4 + -N and SO 4 2 - removal.

Polymers • 2025

The increasing production of bioplastics worldwide requires sustainable end-of-life solutions to minimize the environmental burden. Anaerobic digestion (AD) has been recognized as a potential technology for valorizing waste and producing renewable energy. However, the inherent resistance of certain bioplastics to degradation under anaerobic conditions requires specific strategies for improvement. Thus, in this review, the anaerobic biodegradability of commonly used bioplastics such as polylactic acid (PLA), polyhydroxybutyrate (PHB), polybutylene adipate-co-terephthalate (PBAT), polybutylene succinate (PBS), polycaprolactone (PCL), and starch- and cellulose-based bioplastics are critically evaluated for various operational parameters, including the temperature, particle size, inoculum-to-substrate ratio (ISR) and polymer type. Special attention is given to process optimization strategies, including pretreatment techniques (mechanical, thermal, hydrothermal, chemical and enzymatic) and co-digestion with nutrient-rich organic substrates, such as food waste and sewage sludge. The combinations of these strategies used for improving hydrolysis kinetics, increasing the methane yield and stabilizing reactor performance are described. In addition, new technologies, such as hydrothermal pretreatment and microbial electrolysis cell-assisted AD, are also considered as prospective strategies for reducing the recalcitrant nature of some bioplastics. While various strategies have enhanced anaerobic degradability, a consistent performance across bioplastic types and operational settings remains a challenge. By integrating key recent findings and limitations alongside pretreatment and co-digestion strategies, this review offers new insights to facilitate the circular use of bioplastics in solid waste management systems.

Bioprocess and biosystems engineering • 2025

Electroplating wastewater, characterized by high concentrations of bivalent copper (Cu 2 ⁺) and nickel (Ni 2 ⁺), poses significant environmental and health risks. This study explores the potential of novel Enterococcus species AMZ3, AMZ8, and AMZ5 as biocatalysts in bioelectrochemical systems (BES) for the dual purpose of electricity generation and heavy metal recovery. The strains were isolated from microbial fuel cell (MFC) biofilms and evaluated in single-chamber MFCs and dual-compartment systems. A mixed culture of the strains outperformed individual species, achieving a peak power and current densities of 439.78 mW/m 2 and 5.31 A/m 2 , respectively. In addition, the system achieved a remarkable chemical oxygen demand removal efficiency of 94.6 ± 11.23% and a Coulombic efficiency of 33.7 ± 7.11%. Enhanced electrocatalytic activity in mixed-culture systems was attributed to synergistic microbial interactions, superior biofilm formation, and elevated extracellular polymeric substance protein content. Cyclic voltammetry and electrochemical impedance spectroscopy revealed reduced internal resistance and robust electron transfer pathways in the reactor containing the biofilms of the mixed Enterococcus species. Furthermore, BES with the mixed Enterococcus biofilms achieved copper and nickel removal efficiencies of 99.99 ± 0.01 and 99.96 ± 0.02%, respectively. The reduction and recovery of these metals occurred at the cathode, where copper was predominantly recovered as Cu 0 through bioelectrochemical reduction, while nickel was recovered as metallic Ni 0 through bioelectrochemical reduction, with surface-bound Ni 2 ⁺ also detected, likely formed post-deposition due to oxidative surface processes, as revealed by SEM-EDX, XRD, and XPS analyses. These findings establish the feasibility of mixed Enterococcus cultures in sustainable wastewater treatment, paving the way for scalable BES applications.

Bioresource technology • 2025

Anaerobic digestion (AD) is widely used in waste treatment to produce clean energy such as biogas. However, the excessive ammonia produced during the AD process has a significant inhibitory effect on the microbial system. At present, strategies for alleviating ammonia inhibition have been studied. Among them, microbial electrolysis cell (MEC) emerged as a promising and effective approach in recent years. However, there is still a lack of systematic summary and comprehensive analysis of the mitigation mechanism. Here, ammonia inhibition mechanisms, mitigation mechanisms of MEC and the regulation of microorganisms were comprehensively reviewed. The results show that high ammonia MEC-AD system enhanced the expression of key proteins in hydrogenotrophic methanogens, and methane production shifted from acetoclastic pathway to the hydrogenotrophic pathway. NH 4 + is primarily oxidized at the anode through electrode-mediated pathways and microbial cooperation, enhancing anammox and denitrification gene abundance, promoting NH 4 + and NO 2 - conversion to nitrogen, thereby alleviating ammonia inhibition. This article provides a comparative assessment of MEC-AD and other technologies from the perspectives of technology, environmental sustainability, and economic feasibility. Supported by life cycle assessment, the MEC-AD system exhibits notable advantages in environmental and economic sustainability. However, mechanisms regulating substance conversion and enzyme activity are still unclear in MEC-AD system. In particular, the relationship between active functional microorganisms and their gene expression profiles. Overall, this paper presents the first systematic review of microbial metabolic regulation in high ammonia MEC-AD systems, providing a valuable framework for elucidating the mechanisms of MEC-AD technology alleviates ammonia inhibition. Abbreviations: AD, anaerobic digestion; FAN, free ammonia; VFA, volatile fatty acids; IET, interspecies electron transfer; EPS, extracellular polymeric substance; LCA, life cycle assessment; LCC, life cycle cost; AK, acetate kinase; AmtB, ammonium transfer protein; EAM, electroactive microorganisms; GHGs, greenhouse gas; MF, magnetic field-assistance; AS, air stripping; TAN, total ammonia nitrogen; CH 4 , methane; EET, extracellular electron transfer; DIET, direct interspecies electron transfer; C/N, carbon/nitrogen; MEC, microbial electrolysis cell; HM, hydrogenotrophic methanogenesis; H 4 MPT, tetrahydromethotrexate; ETS, electron transport system; AS, air stripping; SCOD, soluble chemical oxygen demand; CCC-MF, current-carrying-coil-based magnetic field.

Biosensors & bioelectronics • 2025

Acquiring weak electron signals from electroactive bacteria is critical for biosensing, wastewater treatment, and life science applications. However, current microbial electrochemical techniques are inefficient in capturing these signals at microscale. While organic electrochemical transistors can amplify signals exponentially, they lack an effective cathodic reaction to sustain electroactive bacterial dominant communities. Hence, a microbial electrochemical transistor is developed, integrating a microbial electrolytic cell with an organic electrochemical transistor by employing platinum source and drain electrodes. This design enables seamless incorporation of microbial electronic circuits into the ion gated circuits. Results demonstrate effective signal amplification of extracellular electrons generated by microbial gates within the device. The extracellular electron signals are successfully acquired across varying concentrations of organic matter, achieving a substantial signal amplification of ≈ 10 3 . The nonlinear relationship between biodegradable organic matter concentrations and device output signals is established. In continuous mode, a detection limit as low as 1 mgL -1 and a rapid response time of less than 60 s are achieved. This novel device facilitates efficient bacterial signal acquisitions on the microscale, bridges microbial electrochemistry with semiconductor physics, opening new avenues for bioelectronic systems in advancing extracellular electron transfer research, and promises in electroactive bacteria identification at even single-cell level.

Bioresource technology • 2025

Microbial electrolysis cells (MEC) supply electrons to sulfate-reducing bacteria (SRB) within cathode biofilms, however, these SRB exhibit heterogeneous spatial distributions due to varying competitiveness for electron utilization, which ultimately impacts sulfate removal efficiency. This study investigates the underlying mechanisms driving the evolution of this spatial heterogeneity within cathode biofilms and its subsequent influence on sulfate reduction performance by modulating the chemical oxygen demand-to-sulfate (C/S) ratio. When the C/S ratio decreased from 5 to 3, the sulfate removal rate increased by nearly 10 %. At C/S = 5, Bacteroidota and Desulfovibrio were the predominant groups. After the ratio decreased, Synergistota and Aminomonas became dominant. Concurrently, gene abundances associated with assimilatory sulfate reduction (ASR) also increased. Therefore, we conclude that decreasing the C/S from 5 to 3 promotes a more active bacterial region in the biofilm surface, leading to a more efficient spatial stratification of the microbial community and, consequently, improved MEC performance.

Bioresource technology • 2025

To achieve the simultaneous recycling of biogas slurry and anaerobic sludge, the sludge was used to synthesize sludge-based iron-carbon composite mediators (SICM), which were applied to enhance the performance of anaerobic digestion coupled with microbial electrolysis cell (AD-MEC) for biogas slurry degradation. By comparing four preparation methods, it was found that SICM oxygen-containing functional groups and different valence states of iron in SICM played active roles in facilitating electron transfer. Fe@C-B had the best performance of biogas slurry degradation, achieving a COD removal rate of 86.99 %. The methane yield for Fe@C was the greatest at 301.6 mL/gCOD. SICM enhanced AD-MEC performance through selective enrichment of key functional microorganisms such as Fastidiosipila, norank_f_Anaerolineaceae, Geobacter and Methanosaeta. This study demonstrated the feasibility of simultaneously converting biogas slurry into energy and recycling anaerobic sludge, also offering both theoretical and technical support for the sustainable development of biogas projects.

Bioresource technology • 2025

Although platinum-coated cathodes (Pt-C) are commonly applied in microbial electrolysis cell-anaerobic digestion (MEC-AD) systems for methanogenesis, they exhibit inherent biotoxicity. At 0.8 V, Pt-C achieved the highest methane yield (445.71 mL/gCOD), but overall enhancement remained limited. This treatment enhanced inter-biofilm electron transfer processes and electrolyte transport, particularly at cathodes, thereby stimulating quorum sensing, proteolysis, amino acid/peptide transport, and acidification of substrates. It promoted the proliferation of cathodic unclassified_f_Methanobacteriaceae and Geobacteraceae, upregulated hmd, acs and coo, which drove hydrogenotrophic methanogenesis, acetoclastic methanogenesis, and syntrophic acetate oxidation via direct interspecies electron transfer. Conversely, it inhibited formate and methylotrophic methanogenesis pathways and associated genes. Notably, methylotrophic methanogens, despite low abundance, had a disproportionately significant role in methane production. These findings underscore Pt's "double-edged sword" effect, revealing its complex, selective influence on microbial metabolism and methanogenic pathways in MEC-AD systems, providing novel mechanistic insights into optimizing CH 4 production.

Bioelectrochemistry (Amsterdam, Netherlands) • 2025

The increasing need for efficient nitrogen removal in wastewater treatment has driven interest in innovative biological and electrochemical approaches that can simultaneously address ammonium and nitrate contamination. This study explored the performance of simultaneous anodic ammonium oxidation and hydrogenotrophic denitrification in a single-chamber microbial electrolysis cell (MEC). Different operational conditions, including varying ammonia‑nitrogen/nitrate‑nitrogen ratios, were selected to evaluate the MEC's ability to promote anaerobic ammonium oxidation along with organic matter removal. The results demonstrated that the single-stage MEC achieved 57.8 % total nitrogen removal efficiency under an optimal condition where the influent contained only ammonium nitrogen at 200 mg/L with no added nitrate. Adding nitrate in the influent of the microbial electrolysis system decreased ammonium removal in all the operational conditions. Additionally, chemical oxygen demand (COD) destruction and methane production occurred uninterrupted throughout all experimental stages. Therefore, simultaneous methane production and nitrogen removal was realized in this study. The microbial electrolysis system achieved 97.3 ± 0.5 % nitrate removal, outperforming the hydrogenotrophic anaerobic digestion system. While no nitrite accumulation was observed in the systems, nitrous oxide emission occurred in all the operational conditions. A microbial community analysis showed that the anode of the MEC reactor was dominated by Pseudothauera and clostridium, which explained the denitrification performance by the MEC. This highlights the potential of bioelectrochemical systems for simultaneous ammonium and nitrate removal in a single-stage wastewater treatment process.

Journal of hazardous materials • 2025

Constructed wetlands (CWs) are recognized as sustainable wastewater treatment systems. However, their efficiency in removing emerging contaminants such as antibiotics is restricted owing to inherent redox stratification and limited oxygen availability. Electrochemical technologies can effectively enhance antibiotic degradation via an optimized redox environment and increased electron transfer capacity. Nevertheless, the degradation mechanisms and pathways of antibiotics in different electrochemical CWs remain unclear. This study systematically compared the sulfamethoxazole (SMX) removal performance of three electrochemical CWs: microbial fuel cell CW (MFC-CW), micro-electrolysis CW (ME-CW), and electrolytic cell CW (EC-CW). Results demonstrated that SMX removal efficiency in electrochemical CWs increased by 18.6 %-33.4 % due to the synergistic effects of electrochemical oxidation, hydroxyl radical (·OH) oxidation, and microbial degradation. Notably, EC-CW showed a 33.4 % increase in the SMX removal efficiency and a 24.5 % decrease in antibiotic resistance gene (ARG) abundance. Further, it promoted the formation of low-toxicity transformation products, mitigating potential ecological risks. Direct current stimulation selectively enriched SMX-degrading bacteria (e.g., Proteobacteria) and non-ARG-associated microbial communities (e.g., Pseudomonas), effectively enhancing the microbial degradation process (which contributed 36.8 % to SMX degradation). This study provides a scalable and sustainable strategy for treating emerging contaminants in CWs.