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• Electrochemically active biofilms (EABs) can rapidly adapt to low concentrations of tetracycline (C TC ≤ 5 μM) stress. • Adaptation time of EABs increases and catalytic activity decreases at C TC ≥ 10 μM. • EABs exhibit good resilience and anti-shock capacity under chronic/acute TC stress. • EABs' survival strategies are extracellular proteins' secretion and antibiotic efflux. • Geobacter spp. can be selectively enriched under chronic TC stress. Electrochemically active biofilms (EABs) play an ever-growingly critical role in the biological treatment of wastewater due to its low carbon footprint and sustainability. However, how the multispecies biofilms adapt, survive and become tolerant under acute and chronic toxicity such as antibiotic stress still remains well un-recognized. Here, the stress responses of EABs to tetracycline concentrations (C TC) and different operation schemes were comprehensively investigated. Results show that EABs can quickly adapt (start-up time is barely affected) to low C TC (≤ 5 μM) exposure while the adaptation time of EABs increases and the bioelectrocatalytic activity decreases at C TC ≥ 10 μM. EABs exhibit a good resilience and high anti-shocking capacity under chronic and acute TC stress, respectively. But chronic effects negatively affect the metabolic activity and extracellular electron transfer, and simultaneously change the spatial morphology and microbial community structure of EABs. Particularly, the typical exoelectrogens Geobacter anodireducens can be selectively enriched under chronic TC stress with relative abundance increasing from 45.11% to 85.96%, showing stronger TC tolerance than methanogens. This may be attributed to the effective survival strategies of EABs in response to TC stress, including antibiotic efflux regulated by tet (C) at the molecular level and the secretion of more extracellular proteins in the macro scale, as the C=O bond in amide I of aromatic amino acids plays a critical role in alleviating the damage of TC to cells. Overall, this study highlights the versatile defences of EABs in terms of microbial adaptation, survival strategies, and antibiotic resistance, and deepens the understanding of microbial communities' evolution of EABs in response to acute and chronic TC stress. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • Performance of BE-UASB treating high-sulfate methanolic wastewater was evaluated. • BE-UASB exhibited COD removal of 93.6 % with 1.4-fold CH 4 yield of control. • Humics as main components of EPS on electrodes benefited the electron transfer. • Electrocatalysis induced synergy between Acetobacterium and SRB to reduce SO 4 2−. • BE-UASB restructured MPA to alleviate the competition with SRB for electron donors. A bioelectrochemical upflow anaerobic sludge blanket (BE-UASB) was constructed and compared with the traditional UASB to investigate the role of bioelectrocatalysis in modulating methanogenesis and sulfidogensis involved within anaerobic treatment of high-sulfate methanolic wastewater (COD/SO 4 2− ratio ≤ 2). Methane production rate for BE-UASB was 1.4 times higher than that of the single UASB, while SO 4 2− removal stabilized at 16.7%. Bioelectrocatalysis selectively enriched key functional anaerobes and stimulated the secretion of extracellular polymeric substances, especially humic acids favoring electron transfer, thereby accelerating the electroactive biofilms development of electrodes. Methanomethylovorans was the dominant genus (35%) to directly convert methanol to CH 4. Methanobacterium as CO 2 electroreduction methane-producing archaea appeared only on electrodes. Acetobacterium exhibited anode-dependence, which provided acetate for sulfate-reducing bacteria (norank Syntrophobacteraceae and Desulfomicrobium) through synergistic coexistence. This study confirmed that BE-UASB regulated the microbial ecology to achieve efficient removal and energy recovery of high-sulfate methanolic wastewater. [ABSTRACT FROM AUTHOR]

To better understand the underlying mechanisms for methane bioelectrosynthesis, a two-chamber MECs containing a carbon biocathode was developed and studied. Methane production substantially increased with increasing cathode potential. Considerable methane yield was achieved at a poised potential of −0.9 V (vs. Ag/AgCl), reaching 2.30 ± 0.34 mL after 5 h of operation with a faradaic efficiency of 24.2 ± 4.7%. Confirmatory tests done at 0.9 V by switching the type of flushed substrates (CO 2 /N 2 ) or the electrical exposure modes (ON/OFF) demonstrated that cathode serving as an electron donor was the vital driving force for methanogenesis occurring at microbe–electrode surface. Fluorescence in situ hybridization reveled Methanobacteriaceae (particularly Methanobacterium ) was the predominant methanogens, supporting the mechanisms of direct electron transfer between cell-electrode. Additionally, the analysis of scanning electron microscope confirmed that the multiple pathways of electron transfer, including direct cathode-to-cell, interspecies exchange and semi-conductive conduits all together ensured the successful electromethanogenesis process. [ABSTRACT FROM AUTHOR]

The CO 2 bioelectromethanosynthesis via two-chamber microbial electrolysis cell (MEC) holds tremendous potential to solve the energy crisis and mitigate the greenhouse gas emissions. However, the membrane fouling is still a big challenge for CO 2 bioelectromethanosynthesis owing to the poor proton diffusion across membrane and high inter-resistance. In this study, a new MEC bioreactor with biogas recirculation unit was designed in the cathode chamber to enhance secondary-dissolution of CO2 while mitigating the contaminant adhesion on membrane surface. Biogas recirculation improved CO 2 re-dissolution, reduced concentration polarization, and facilitated the proton transmembrane diffusion. This resulted in a remarkable increase in the cathodic methane production rate from 0.4 mL/L·d to 8.5 mL/L·d. A robust syntrophic relationship between anodic organic-degrading bacteria (Firmicutes 5.29%, Bacteroidetes 25.90%, and Proteobacteria 6.08%) and cathodic methane-producing archaea (Methanobacterium 65.58%) enabled simultaneous organic degradation, high CO 2 bioelectromethanosynthesis, and renewable energy storage. [Display omitted] • The biogas circulation unit was introduced in MECs to prevent membrane fouling. • Great increase in cathode methane yield was achieved due to the biogas unit. • Shear-scouring effect reduced proton exchange membrane contamination. • Biodegradation of organic matters supplied the sufficient e−/H+ for CO 2 methanation. • Microbial symbiosis enabled organic degradation, and simultaneous CO 2 methanation. [ABSTRACT FROM AUTHOR]

The over-dosing use of chloroquine phosphate (CQ) poses severe threats to human beings and ecosystem due to the high persistence and biotoxicity. The discharge of CQ into wastewater would affect the biomass activity and process stability during the biological processes, e.g., anammox. However, the response mechanism of anammox consortia to CQ remain unknown. In this study, the accurate role of extracellular polymeric substances barrier in attenuating the negative effects of CQ, and the mechanism on cytotoxic behavior were dissected by molecular spectroscopy and computational chemistry. Low concentrations (≤6.0 mg/L) of CQ hardly affected the nitrogen removal performance due to the adaptive evolution of EPS barrier and anammox bacteria. Compact protein of EPS barrier can bind more CQ (0.24 mg) by hydrogen bond and van der Waals force, among which O-H and amide II region respond CQ binding preferentially. Importantly, EPS contributes to the microbiota reshape with selectively enriching Candidatus_Kuenenia for self-protection. Furthermore, the macroscopical cytotoxic behavior was dissected at a molecular level by CQ fate/distribution and computational chemistry, suggesting that the toxicity was ascribed to attack of CQ on functional proteins of anammox bacteria with atom N17 (f –=0.1209) and C2 (f +=0.1034) as the most active electrophilic and nucleophilic sites. This work would shed the light on the fate and risk of non-antibiotics in anammox process. [Display omitted] • Fate and distribution of chloroquine phosphate (CQ) in anammox were deciphered. • EPS configuration change and binding mechanism between EPS and CQ were unraveled. • Antioxidation defense mechanism of anammox bacteria to CQ was dissected. • EPS conduced to selectively enrich Candidatus Kuenenia for microbiota reshape. • Molecular mechanism on attack behavior of CQ to intracellular protein was revealed. [ABSTRACT FROM AUTHOR]

• Biogas yield increased by 32.1 % in EC-AnMBR compared to traditional AnMBR. • Long-term operation of EC-AnMBR stimulated enrichment of keystone electro-microbes. • Composite anode membrane (CAM) upgraded the functional genes in metabolic pathways. • CAM stimulated transfer of electrons and degradation of organic pollutants. • EC-AnMBR uniquely shaped the spatio-temporal distribution of microbial communities. Electrochemical anaerobic membrane bioreactor (EC-AnMBR) by integrating a composite anodic membrane (CAM), represents an effective method for promoting methanogenic performance and mitigating membrane fouling. However, the development and formation of electroactive biofilm on CAM, and the spatio-temporal distribution of key functional microorganisms, especially the degradation mechanism of organic pollutants in metabolic pathways were not well documented. In this work, two AnMBR systems (EC-AnMBR and traditional AnMBR) were constructed and operated to identify the role of CAM in metabolic pathway on biogas upgrading and mitigation of membrane fouling. The methane yield of EC-AnMBR at HRT of 20 days was 217.1 ± 25.6 mL-CH 4 /g COD, about 32.1 % higher compared to the traditional AnMBR. The 16S rRNA analysis revealed that the EC-AnMBR significantly promoted the growth of hydrolysis bacteria (Lactobacillus and SJA-15) and methanogenic archaea (Methanosaeta and Methanobacterium). Metagenomic analysis revealed that the EC-AnMBR promotes the upregulation of functional genes involved in carbohydrate metabolism (gap and kor) and methane metabolism (mtr, mcr, and hdr), improving the degradation of soluble microbial products (SMPs)/extracellular polymeric substances (EPS) on the CAM and enhancing the methanogens activity on the cathode. Moreover, CAM biofilm exhibits heterogeneity in the degradation of organic pollutants along its vertical depth. The bacteria with high hydrolyzing ability accumulated in the upper part, driving the feedstock degradation for higher starch, sucrose and galactose metabolism. A three-dimensional mesh-like cake structure with larger pores was formed as a biofilter in the middle and lower part of CAM, where the electroactive Geobacter sulfurreducens had high capabilities to directly store and transfer electrons for the degradation of organic pollutants. This outcome will further contribute to the comprehension of the metabolic mechanisms of CAM module on membrane fouling control and organic solid waste treatment and disposal. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • Redox-active molecules secreted by microbes are reduced in the presence of CNTs. • Supply of CNTs can improve interspecific syntrophy and microbial carbon metabolism. • Supply of CNTs improve electron transfer kinetic rate constants of all four steps. • CNTs combined with outer membrane cytochromes enhance interfacial electron exchange. • Substrate uptake by microbial cell is rate-limiting step. Supply of carbon-based nanomaterials (e.g., carbon nanotubes, CNTs) to develop highly conductive electrochemically active biofilms (EABs) is a potential strategy for facilitating extracellular electron transfer (EET) in bioelectrochemical systems (BESs). Understanding of the underlying CNTs-mediated EET behaviors is helpful to further advance the practical application of BESs. Here, the cognitive influence of CNTs on bioelectrocatalytic activity and electron transfer efficiency of EABs were elucidated. CNTs can be embedded into EABs to form hybrid conductive biofilms (CNTs/EABs), achieving a high current density (7.4 ± 1.40 A m−2) and excellent coulombic recovery (46.0 ± 2.70 %) over 100 days of steady operation. The supply of CNTs can mitigate the dependence of exoelectrogens (such as Geobacter) on outer membrane cytochromes (OMCs) and conductive pili due to their down-regulated genes expression in CNTs/EABs, but it can significantly improve microbial carbon metabolism because physically high-conductive CNTs can establish rapid EET pathways, which may reduce the necessity for cells to invest metabolic energy in producing conductive pili and cytochromes that are required in the absence of CNTs. Such enhancement in electron transfer rate may be caused by the interfacial interaction between OMCs and CNTs, resulting in an order of magnitude higher than in the control (5.5 ± 1.60 s−1 vs. 0.28 ± 0.04 s−1) and without compromising of mass diffusion. This study provides comprehensive insight into the role of carbon-based nanomaterials in provoking interfacial electron transfer and renewable energy recovery. [ABSTRACT FROM AUTHOR]

Sludge management represents a critical challenge because of complex compositions and poor dewaterability. Fe2+-activated persulfate oxidation (Fe2+/S 2 O 8 2−) is an effective, and widely investigated method for enhancing sludge dewatering. However, the potential effects of Fe2+/S 2 O 8 2− on sludge drying efficiency, anaerobic biodegradation behaviors and potential recycling of sludge residua are not yet well-known. In this study, a new sludge disposal route (step i: enhanced dewatering via Fe2+/S 2 O 8 2−, and step ii: drying-incineration or anaerobic digestion) was proposed and appraised comprehensively. Results showed that Fe2+/S 2 O 8 2− oxidation destroyed extracellular polymeric substances, lysed sludge cells and enhanced the dewaterability greatly. Capillary suction time and mechanical filtration time at 2.0/1.6 mmol-Fe2+/S 2 O 8 2−/g-VS decreased by 88.0% and 79.6%, respectively. Moreover, 89.8% of micro-pollutants (e.g., methylbenzene, ethylbenzene, p -m-xylene and o -xylene) in sludge were removed. Besides, the pretreatment was able to alter sludge drying behaviors and methane-producing potential. Pretreated sludge exhibited faster drying rate and shorter lag-time for methane production. Incineration residua of dewatered sludge could be re-coupled with S 2 O 8 2− as the conditioner to enhance sludge dewaterability, thereby reducing the chemical input and disposal cost. This study provides a novel, self-sustainable strategy for sludge management, reutilization and final safe disposal. • A comprehensive sludge treatment route was proposed. • The capillary suction time of sludge was reduced by 87.9% within 1 min. • Fe2+/S 2 O 8 2− pretreatment efficiently removed micro-pollutants. • Fe2+/S 2 O 8 2− pretreatment reduced mechanical filtration and drying time. • Sludge ash can replace Fe2+ to activate S 2 O 8 2− for improving sludge dewaterability. [ABSTRACT FROM AUTHOR]

[Display omitted] • nZVI enhanced CH 4 yield of sludge in an anaerobic continuous stirred tank reactor. • nZVI promoted CH 4 bioconversion by serving as trace element and electron donors. • Organics-degrading bacteria and hydrogenotrophic methanogens were enriched. • Subsequent digested sludge dewaterability were enhanced at nZVI 160 mg/g-TS. Underlying mechanism of continuous nano zero-valent iron (nZVI) supply in functional microbes enrichment and methane bioconversion of waste activated sludge were investigated in a lab-scale continuous stirred tank reactor (CSTR). Results indicated that methane productivity strongly relied on nZVI dosage (R = 0.998, p (0.05) < 0.001) and leached Fe2+ concentration (R = 0.943, p (0.05) = 0.005). The higher nZVI dosage, the higher methane productivity and organic removal were achieved. The methane production rate reached 77.6 ± 9.7 mL/g-VS/d at 160 mg-nZVI/g-TS, increasing by 2.3 times than the phase without nZVI supply. The corrosion/dissociation of nZVI, except for serving as trace element and electron donors (H 2 /[H]), increased system buffering capacity (2835–3410 mg CaCO 3 /L), and decreased oxidation reduction potential from − 152 mV to − 240 mV. Such thermodynamically favorable environment facilitated the proliferation of organics-degrading bacteria (Firmicutes , Chloroflexi , Smithella , etc.) and hydrogenotrophic methanogen (Methanobacterium). As a result, more large organic molecules such as proteins and polysaccharides were hydrolyzed into short-chain fatty acids, thus enhancing the methanogenesis. Furthermore, the continuous supply of nZVI regulated the colloidal properties of sludge flocs by altering particle size distribution and zeta potential via flocculation effect of the released Fe2+ (136.4 ± 12.1 mg/L). The dewaterability of digested sludge was improved to a certain extent, with capillary suction time dropping to 84.8 ± 4.1 s. This study provided a more systematic understanding of the role of nZVI in promoting methane bioconversion and subsequent digested sludge dewatering and volume reduction, thus expanding the potential application of nZVI in real-world scenarios. [ABSTRACT FROM AUTHOR]

[Display omitted] • UF-HF-AnMBR system showed excellent capability in treating PTA wastewater. • The methane yield was 0.345 ± 0.028 L·g-COD removed −1 at a steady state. • The optimum HRT was 16 h when considering microbial community structure. • Membrane separation promoted particles agglomeration and sludge regranulation. • The dominant methanogen and syntroph were Methanosaeta and Pelotomaculum. Up-flow anaerobic sludge blanket is a representative way to treat high-strength industrial wastewater, but suffers from granule collapse and poor long-term performance. In this study, a dual-chamber up-flow fluidized hollow-fiber anaerobic membrane bioreactor (UF-HF-AnMBR) was constructed to enhance sludge regranulation and process stability for purified terephthalic acid (PTA) wastewater treatment. A stable and satisfactory aromatic compound removal (>99 %) was achieved at the organic loading rate of 7.15 ± 0.21 g-COD·L reactor −1·d−1, with the methane yield of 0.345 ± 0.028 L·g-COD removed −1. Although the granular sludge collapsed initially induced the pore blocking and membrane fouling, membrane separation promoted the agglomeration of small particles, sludge regranulation and biomass retention. Parallel factor analysis identified that the amino acid tryptophan in extracellular polymeric substances exerted a more critical effect on membrane fouling. The 16S rRNA and network analysis revealed the robust proliferation/enrichment of Methanosaeta , Pelotomaculum , etc., as well as the establishment of mutualistic symbiotic relationship among different species, ensured a stable microbial community and created a favorable circumstance for highly effective anaerobic treatment of PTA wastewater. This study proves that UF-HF-AnMBR can be an efficient and promising technique for sludge regranulation and microbe enrichment, advancing its application in PTA wastewater treatment and bioenergy recovery. [ABSTRACT FROM AUTHOR]

• In-depth analysis of sludge properties was conducted in seven representative cities. • Show the area properties of microbe & antibiotic resistance genes (ARGs) in sludge. • Relationship of ARGs, population, and economy was analyzed by co-occurrence network. • Fe(II)-S 2 O 8 2− oxidation achieved efficient sludge dewatering and ARGs removal. Waste activated sludge properties vary widely with different regions due to the difference in living standards and geographical distribution, making a big challenge to developing a universally effective sludge dewatering technique. The Fe(II)-activated persulfate (S 2 O 8 2−) oxidation process shows excellent ability to disrupt sludge cells and extracellular polymeric substances (EPS), and release bound water from sludge flocs. In this study, the discrepancies in the physicochemical characteristics of sludge samples from seven representative cities in China (e.g., dewaterability, EPS composition, surface charge, microbial community, relative abundance of antibiotic resistance genes (ARGs), etc.) were investigated, and the role of Fe(II)-S 2 O 8 2− oxidation in enhancing removal of antibiotic resistance genes and dewatering ability were explored. The results showed significant differences between the EPS distribution and chemical composition of sludge samples due to different treatment processes, effluent sources, and regions. The Fe(II)-S 2 O 8 2− oxidation pretreatment had a good enhancement of sludge dewatering capacity (up to 76 %). Microbial analysis showed that the microbial community in each sludge varied significantly depending on the types of wastewater, the wastewater treatment processes, and the regions, but Fe(II)-S 2 O 8 2− oxidation was able to attack and rupture the sludge zoogloea indiscriminately. Genetic analysis further showed that a considerable number of ARGs were detected in all of these sludge samples and that Fe(II)-S 2 O 8 2− oxidation was effective in removing ARGs by higher than 90 %. The highly active radicals (e.g., SO 4 −·, ·OH) produced in this process caused drastic damage to sludge microbial cells and DNA stability while liberating the EPS/cell-bound water. Co-occurrence network analysis highlighted a positive correlation between population distribution and ARGs abundance, while variations in microbial communities were linked to regional differences in living standards and level of economic development. Despite these variations, the Fe(II)-S 2 O 8 2− oxidation consistently achieved excellent performance in both ARGs removal and sludge dewatering. The significant modularity of associations between different microbial communities also confirms its ability to reduce horizontal gene transfer (HGT) by scavenging microbes. [Display omitted] [ABSTRACT FROM AUTHOR]

In the present work, with the addition of ZnO nanoparticles (NPs) as Zn source, the Zn-incorporated TiO 2 coatings were successfully produced by the facile one-step micro-arc oxidation (MAO) method. The influence of current density on the microstructural features and biological properties of Zn-incorporated TiO 2 MAO coatings were systematically examined. It is revealed that, at a relatively low current density of 0.1 A/cm2, Zn species either locate on the coating surface as ZnO nano-sheet clusters or entrap within the coating. By contrast, Zn species tend to fuse into the coating at a relatively high current density of 0.5 A/cm2, which exhibits a three-layered structure with significant difference of crystallinity, composition and morphology between different layers. The biological experiments indicate that different current densities result in different osteogenic activities and antibacterial properties of Zn-incorporated TiO 2 coatings. The presence of a Zn-depleted amorphous outer-layer on the MAO coating produced at the current density of 0.5 A/cm2 favours the deposition of apatite-like phases, but retards the release of Zn ions, which thus results in its higher osteogenic activity with lower antibacterial capability compared to that produced at the current density of 0.1 A/cm2. In summary, dual-functional Zn-incorporated TiO 2 coatings could be successfully produced through the facile one-step MAO method, with both antibacterial property and bone formability significantly affected by the current density of MAO process. • Dual-functional Zn-incorporated TiO 2 coatings are successfully produced using one-step micro-arc oxidation method with ZnO nanoparticles as Zn source. • The coating formation process is closely associated with the energy released pre discharge site. • A three-layered Zn-incorporated TiO 2 coating could be fabricated through micro-arc oxidation at the current density of 0.5 A/cm2. • Antibacterial property and bone formability of Zn-incorporated TiO 2 coatings are closely associated with their microstructural features. • Biological properties could be controlled by adjusting the current density of micro-arc oxidation process. [ABSTRACT FROM AUTHOR]

Anaerobic membrane bioreactor (AnMBR) holds great promise to treat a broad range of waste streams for concurrent pollutants transformation and biofuels harvest while producing less digestate residuals. In this review, recent research advances, new discoveries and commercial application status of AnMBR technique were summarized and reported. A comprehensive comparison analysis designed herein demonstrated its fascinating superiorities over the conventional activated sludge-based processes with regards to good permeate quality, less digestate residuals, low operational costs, net profit/energy output, and outstanding economic and environmental benefits. Despite the great progress achieved previously, there are still numerous challenges head for AnMBR platform applications to be tackled, particularly for severe membrane fouling, low methane content in biogas, highly dissolved methane, poor ammonia removal and phosphorus recovery, etc. To address the above problems, a new-generation process, i.e. so-called "Integrated Multistage Bio-Process (IMBP)" constituted of solar-driven bioelectrochemical system (BES)-AnMBR, partial nitritation/anammox (PN/A), nitrate reduction via anaerobic oxidation of methane (AOM) and biological/chemical phosphorus precipitation units, was proposed in this article, with versatile capabilities in simultaneous biowastes valorization, CO 2 electromethanogenesis and simultaneous biogas upgrading, in-situ fouling control, ammonia removal, dissolved methane reutilization, and phosphorus recover as hydroxyapatite-rich nutrients. Despite the uncertainties about whether this approach possesses the powerful potential to dominate the future, but most surely, this hybrid concept will enhance the deployment and industrial competitiveness of AnMBR-based technologies in real-world scenarios, facilitating the establishment of the energy-sustainable and low-carbon society. Of course, more efforts are still required to demonstrate the feasibility of this integrated biorefinery approach. Nonetheless, this review opens up new research opportunities to integrate with other newly emerging processes to develop robust, multifunctional and sustainable AnMBR-based technologies towards biowaste biorefinery, chemical energy harvest and green, carbon-neutral society. Image 1 • Advances in anaerobic membrane bioreactor for biowaste valorization were reviewed. • Technical issues limiting the commercial applications of AnMBR were discussed. • A comprehensive comparison for five different treatment processes was conducted. • A multifunctional process for biowaste treatment and bioenergy recovery was proposed. • Future perspectives of AnMBR in real-world applications were elucidated. [ABSTRACT FROM AUTHOR]

To investigate the impact of sulfate (SO 4 2−) on the performance of bioelectrochemical up-flow anaerobic sludge blanket (BE-UASB), the COD/SO 4 2− ratio of sulfate-containing methanolic wastewater was gradually decreased from 20 to 3. The results showed that BE-UASB maintained higher COD and SO 4 2− removal (i.e., 91% and 70%, respectively) with methane production rate of 278.7 mL/L reactor /d at COD/SO 4 2− ratio from 10 to 5, ensuring efficient energy recovery. Sulfidogenesis enabled the sludge re-granulation while bioelectrocatalysis further contributed to the growth/proliferation of biomass with interwoven filaments, rods, and spherical microorganisms. 16 S rRNA gene analysis demonstrated that bioelectrocatalysis promoted the diversity of methane-producing archaea (MPA), including Methanomethylovorans , Methanosaeta , Candidatus_Methanofastidiosum , and Methanobacterium. Sulfate-reducing bacteria (SRB), mainly comprising G_norank_f_Syntrophobacteraceae , Desulfomonile , and Syntrophobacter , tended to be enriched on bioelectrodes, which not only eased the competition with MPA but also achieved simultaneous removal of COD and SO 4 2− in synergy with MPA. [Display omitted] • SRB and MPA synergistically remove COD and increase CH 4 yield by 50% in BE-UASB. • Sludge regranulation was obtained by SO 4 2− and bioelectrocatalytic stimulation. • Archaea shifted to methylotrophic methanogens as SO 4 2− concentration increased. • The competition between MPA and SRB was alleviated in BE-UASB. [ABSTRACT FROM AUTHOR]

• Synergistic effect of sludge and food waste anaerobic co-digestion was studied. • Three kinetic models were employed and compared. • The SS:FW ratios of 0.5:0.5 achieved the best digestion performance. • Cone model more accurately described the biodegradation kinetics of co-digestion. • The synergy improved hydrolysis rate and upgraded methanogenesis. Anaerobic co-digestion has attracted much attention due to its unique advantages compared with the anaerobic mono-digestion. In this work, the synergistic effect and biodegradation kinetics of sewage sludge (SS) and food waste (FW) were studied during anaerobic co-digestion. Biochemical methane potential (BMP) assay and three kinetic models were used to detect and analyze methane production potential during co-digestion under different ratios of SS and FW. The SS:FW ratios of 0.5:0.5 showed very high methane recovery, with the methane productivity increasing by 4.59 times (50.30 ± 10.37 mL/g-VS/day), the lag-phase shortening by 11.53 times (0.182 day) and the hydrolysis rate increasing by 3.88 times (0.334/day) compared with the SS mono-digestion. Moreover, correlation model parameter analysis indicated the Cone model has the best fitness to the experimental data. These results confirmed the superiority of co-digestion and the existence of synergy, which can greatly accelerate the biodegradation process and more effectively recover bioenergy. [ABSTRACT FROM AUTHOR]

• Tetracycline in water was effectively degraded by sludge templated TiO 2 samples. • Graphene-like carbon structure was found in sludge-TiO 2. • Transition metals and Carbon dopants in photocatalyst fastens the electron transfer. • The gas emission and mechanism of sludge-TiO 2 synthesis process were investigated by TG-IR. Two types of novel municipal sewage sludge (SS) combined TiO 2 photocatalysts (ST 1 and ST 2) were synthesized through calcination treatment under different atmospheres (air and N 2). The morphology, structure, and chemical states of photocatalysts were characterized by SEM, XRD, EDS, FT-IR, Raman UV–Vis, BET, and TG-IR. The results showed that ST 2 consisted of a mesoporous graphene-like structure (20.02 nm) displayed exhibited better visible light photocatalytic performances and the highest BET surface area and pore volume (92.97 m2 g−1 and 0.46 cm3/g). The doping of Carbon and transition metals (Al, Mg) in TiO 2 strengthened visible-light response by lowering the band gap. The photocatalytic ability is evaluated in the degradation of tetracycline, which is a typical antibiotic in the aquatic environment. The ST 2 photocatalytic efficiency under visible light than that of ST 1 and TiO 2. The enhancement is formed together by porous surface and lower band gap of ST 2 , which could offer more active sites and facilitate faster electron-hole pair separation. In addition, the sludge-TiO 2 calcination in N 2 (ST 2) has the potential to reduce CO 2 emission while recovering more energy from the sludge, which turned out to be a more cost-effective way to reutilization of sewage sludge compared with that of calcination in air. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Current status of MECs for CO 2 electromethanogenesis was summarized. • The working principles of CO 2 electromethanogenesis were summarized. • Several test methods was proposed to analyze the properties. • The critical factors effecting CH 4 production have been discussed. Abstract Given the aggravated greenhouse effect caused by CO 2 and the current energy shortage, CO 2 capture and reuse has been gaining ever-increasing concerns. Microbial Electrolysis Cells (MECs) has been considered to be a promising alternative to recycle CO 2 bioelectrochemically to low-carbon electrofuels such as CH 4 by combining electroactive microorganisms with electrochemical stimulation, enabling both CO 2 fixation and energy recovery. In spite of the numerous efforts dedicated in this field in recent years, there are still many problems that hinder CO 2 bioelectroconversion technique from the scaling-up and potential industrialization. This review comprehensively summarized the working principles, extracellular electron transfers behaviors, and the critical factors limiting the wide-spread utilization of CO 2 electromethanogenesis. Various characterization and electrochemical testing methods for helping to uncover the underlying mechanisms in CO 2 electromethanogenesis have been introduced. In addition, future research needs for pushing forward the development of MECs technology in real-world CO 2 fixation and recycling were elaborated. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel sandwich-type carbon felt-PVDF composite membrane was developed. • Use of composite anodic membrane increased methane yield (358.5 mL/d) by 12.8%. • Composite anodic membrane inactivated around 97.9% of pathogens. • Biofouling mitigation was obtained by the effect of anodic oxidation. • Archaea shifted to hydrogenotrophic methanogens with electrostimulation. Membrane fouling presents a big challenge for the real-world implementation of anaerobic membrane bioreactors (AnMBRs) in digesting high-solid biowastes. In this study, an electrochemical anaerobic membrane bioreactor (EC-AnMBR) with a novel sandwich-type composite anodic membrane was designed and constructed for controlling membrane fouling whilst improving the energy recovery. The results showed that EC-AnMBR produced a higher methane yield of 358.5 ± 74.8 mL/d, rising by 12.8% compared to the AnMBR without applied voltage. Integration of composite anodic membrane induced a stable membrane flux and low transmembrane pressure through forming an anodic biofilm while total coliforms removal reached 97.9%. The microbial community analysis further provided compelling evidence that EC-AnMBR enriched the relative abundance of hydrolyzing (Chryseobacterium 2.6%) bacteria and methane-producing (Methanobacterium 32.8%) archaea. These findings offered new insights into anti-biofouling performance and provided significant implications for municipal organic waste treatment and energy recovery in the new EC-AnMBR. [ABSTRACT FROM AUTHOR]

[Display omitted] • Electrochemical membrane reactor was designed to co-digest sludge and food waste. • Functional electroactive microorganisms were proliferated on bioelectrodes. • Robust synergy of various microorganisms improved anaerobic co-digestion. • 2.76-time increase in methane production was obtained in the optimized conditions. • Electrostatic repulsion and electrochemical oxidation mitigated membrane fouling. Membrane fouling remains a big challenge hindering the wide-application of anaerobic membrane bioreactor (AnMBR) technology. In this study, an electrochemical anaerobic membrane bioreactor (EC-AnMBR) was developed by coupling electrochemical regulation to enhance co-digestion of sewage sludge and food waste and mitigate membrane fouling. The highest methane production (0.12 ± 0.02 L/L reactor /day) and net energy recovery (31.82 kJ/day) were achieved under the optimum conditions of 0.8 V, hydraulic retention time of 10 days and solids retention time of 50 days. Electrochemical regulation accelerated the mineralization of high-molecular-weight organics and reinforced the membrane antifouling ability by inducing electrostatic repulsive force and electrochemical oxidation. Besides, symbiotic relationships among functional microorganisms (Spirochaetes , Methanolinea , etc.) were enhanced, improving the hydrolysis and methanogenesis processes of complex organics and the long-term stability. This study confirms the technical feasibility of EC-AnMBR in treating high-solid biowastes, and provides the fundamental data to support its application in real-world scenarios. [ABSTRACT FROM AUTHOR]

[Display omitted] • Effect of bioelectrocatalysis on sludge re-granulation was firstly studied. • BE-UASB operated optimally at 0.8 V with 388 mLCH 4 /L reactor /d and 90% COD removal. • Methanol acted as mediator could enhance CO 2 bioconversion by electron transfer. • Bioelectrocatalysis stimulated the EPS secretion to form anaerobic granular sludge. • BE-UASB restructured microbial community and diversified metabolic pathways. Granular sludge disintegration and washing out pose a challenge to up-flow anaerobic sludge bed (UASB) reactor treating methanolic wastewater. Herein, in-situ bioelectrocatalysis (BE) was integrated into UASB (BE-UASB) reactor to alter microbial metabolic behaviors and enhance the re-granulation process. BE-UASB reactor exhibited the highest methane (CH 4) production rate of 388.0 mL/L reactor /d and chemical oxygen demand (COD) removal of 89.6 % at 0.8 V. Sludge re-granulation was strengthened with particle size over 300 µm of up to 22.4%. Bioelectrocatalysis stimulated extracellular polymeric substances (EPS) secretion and formation of granules with rigid [-EPS-cell-EPS-] matrix by enhancing the proliferation of key functional microorganisms (Acetobacterium , Methanobacterium , and Methanomethylovorans) and diversifying metabolic pathways. Particularly, a high Methanobacterium richness (10.8%) drove the electroreduction of CO 2 into CH 4 and reduced its emissions (52.8%). This study provides a novel bioelectrocatalytic strategy for controlling granular sludge disintegration, which will facilitate the practical application of UASB in methanolic wastewater treatment. [ABSTRACT FROM AUTHOR]

In this work, the performance of dual-chamber microbial fuel cells (MFCs) constructed either with commonly used Nafion ® proton exchange membrane or supported ionic liquid membranes (SILMs) was assessed. The behavior of MFCs was followed and analyzed by taking the polarization curves and besides, their efficiency was characterized by measuring the electricity generation using various substrates such as acetate and glucose. By using the SILMs containing either [C 6 mim][PF 6 ] or [Bmim][NTf 2 ] ionic liquids, the energy production of these MFCs from glucose was comparable to that obtained with the MFC employing polymeric Nafion ® and the same substrate. Furthermore, the MFC operated with [Bmim][NTf 2 ]-based SILM demonstrated higher energy yield in case of low acetate loading (80.1 J g −1 COD in m −2 h −1 ) than the one with the polymeric Nafion ® N115 (59 J g −1 COD in m −2 h −1 ). Significant difference was observed between the two SILM-MFCs, however, the characteristics of the system was similar based on the cell polarization measurements. The results suggest that membrane-engineering applying ionic liquids can be an interesting subject field for bioelectrochemical system research. [ABSTRACT FROM AUTHOR]

Clean water shortages require the reuse of wastewater. The presence of organic substances such as humic acids in wastewater makes the water treatment process more difficult. Humic acids can significantly affect the removal of heavy metals and other such toxins. Humic acids is formed by the decomposition and transformation of animal and plant remains by microorganisms, and naturally exists in soil and water. It is necessary to degrade and remove humic acids from wastewater. As it seriously human health, effective technologies for removing humic acids from wastewater have attracted great interest over the past decades. This study compared existing techniques for removing humic acids from wastewater, as well as their limitations. Physicochemical treatments including filtration and oxidation are basic and key approaches to removing humic acids. Biological treatments including enzyme and fungi-mediated humic acids degradation are economically feasible but require some scalability. In conclusion, the integrated treatment processes are more significant options for the effective removal of humic acids from wastewater. In addition, humic acids have rich utilization values. It can improve the soil, increase crop yields, and promote the removal of pollutants. [Display omitted] • Organic matter (humic acids) removal from wastewater helps to solve water shortage. • Physiochemical techniques have higher efficiency in humic acid removal. • Biological approaches are more cost-effective as compared to physiochemical. • Extracted humic acids have several technological applications. [ABSTRACT FROM AUTHOR]

Energy crisis and increasing rigorous management standards pose significant challenges for solid waste management worldwide. Several emerging diseases such as COVID-19 aggravated the already complex solid waste management crisis, especially sewage sludge and food waste streams, because of the increasingly large production year by year. As mature waste disposal technologies, landfills, incineration, composting, and some other methods are widespread for solid wastes management. This paper reviews recent advances in key sewage sludge disposal technologies. These include incineration, anaerobic digestion, and valuable products oriented-conversion. Food waste disposal technologies comprised of thermal treatment, fermentation, value-added product conversion, and composting have also been described. The hot topic and dominant research foci of each area are summarized, simultaneously compared with conventional technologies in terms of organic matter degradation or conversion performance, energy generation, and renewable resources production. Future perspectives of each technology that include issues not well understood and predicted challenges are discussed with a positive effect on the full-scale implementation of the discussed disposal methods. [Display omitted] • The existing methods of waste disposal are inefficiency and costly. • Technology fusion of waste treatment shows promise in energy resource recovery. • Predicted challenges of waste management procedures have achieved positive outcomes. • The rise of new technologies and Synergies maximizes recovery from waste treatment. [ABSTRACT FROM AUTHOR]

[Display omitted] • The UBF performed optimal NRE of 93.19 ± 3.39 %. • The tryptophan-like proteins in EPS was vital for granules formation. • The PN and lipids serve as skeleton, while PS can promote cell aggregation. • The co-existing spatial structure was developed between AnAOB and AOB. Granule formation, microstructure and microbial spatial distribution are crucial to granule stability and nitrogen removal. Here, an upflow blanket filter (UBF) reactor with porous fixed cylinder carriers was fabricated and operated for 234 days to investigate overall performance and the formation mechanism of anammox granules. Results showed that the UBF performed the highest nitrogen removal efficiency of 93.19 ± 3.39% under nitrogen loading rate of 3.6 kg-N/m3/d and HRT of 2 h. The tryptophan-like proteins as the key component in EPS were vital for granules formation. Further 16 s rRNA analysis indicated that SBR1031 with a relative abundance of 40.5% played an important role in cell aggregation. Thus, anammox granules were developed successfully with a two-layered spatial structure where outer-layer was ammonia oxidizing bacteria and inner-core was anaerobic ammonia oxidizing bacteria. Together, introduction of porous fixed cylinder carriers is a valid method to avoid biomass loss and floatation. [ABSTRACT FROM AUTHOR]

[Display omitted] • Enrichment procedure of electrochemically active biofilms was visualized. • Exopolysaccharides and eDNA contributed to biofilms formation at early stage. • Anaerobic respiration-related genes were upregulated under R ext 500 Ω. • Electron transfer rate was mainly controlled by biofilm resistance. Charge transfer resistance (CTR) is a key operating parameter for regulating energy harvesting efficiency, electrochemically active biofilms (ECABs) development, and microbial diversity and metabolism in microbial fuel cell (MFC). However, the response behaviors in terms of electroactivity, spatio-temporal distribution, and catabolic pathway of mixed-culture ECABs when being exposed to different CTR have not been well understood. Herein, we comprehensively investigated the effects of CTR on the characteristics of ECABs by varying external resistance in MFC. Specifically, R 3 -500 exhibited short ECABs maturation (∼8 d), high energy output (∼0.37 W m−2, ∼0.4 mA cm−2), low internal resistance (∼355 Ω) when ECABs was mature, and highly efficient and stable operation. Exopolysaccharides and extracellular DNA play critical roles in cells attachment on electrode surface and development a steady biofilms skeleton. The electron transfer rate was controlled by biofilm resistance (R film , > 90% of total internal resistance), and a typical two-layer ECABs structure (inner dead layer and outer live layer) colonized on carbon fiber, with the dead-cells bearing inner layer as the major resistance causing increased R film. Metagenomics analysis revealed that R 3 -500 facilitated the proliferation and co-existence of electricigens (e.g., Geobacter), and putative electric-syntrophy bacteria (e.g., Trichococcus), building a syntrophic relationship for potential interspecies electron/message exchange. Furthermore, the key functional genes families associated with cell activity (such as fts Z, and rps / rpl series), electron transfer (such as torC , rib series, and pilA), and energy metabolism (hdr , mcr , fwd / fmd , and ntp) were upregulated (1.33–6.67-fold) in R 3 - 500. Together these insights into ECABs' behaviors by regulating CTR are of potential significance to help to sustain the long-term, highly active operation in bioelectrochemical systems. [ABSTRACT FROM AUTHOR]

• Increasing mass of waste needs an effective and sustainable treatment process. • Conventional waste treatment procedures are expensive. • Fungi offer more sustainable and cost-effective management of waste-activated sludge. • Fungi use waste-activated sludge as a substrate and excrete value-aided products. Production of vast amounts of waste material routinely has prompted the interest of researchers to conserve and manage biomass waste. The recycling of organic waste material could produce various value-added bioproducts beneficial for human beings and the environment. Traditional decomposition methods have been reported, but the efficiency of these fermentation methods was comparatively low and expensive, limiting their use. Currently, researchers have moved their concern toward green pretreatment methods, including enzymatic techniques and biological decomposition purposes. Among biological sources, the fungal fermentation system has offered a more efficient and sophisticated method because of higher production of bioproducts, greater efficiency, environmentally safe, and cost-effectiveness compared to previous methods. The present study reviewed the advantages of fungi-mediated conversion of waste-activated sludge into value-added bioproducts to help the researchers in sustainable management of waste and shed light on limitations of previous methods. [ABSTRACT FROM AUTHOR]

[Display omitted] • The effect of anolyte circulation in microbial electrolysis cell was investigated. • Semi-continuous anolyte circulation increased CH 4 yield by 5.4 times. • PEM fouling impeding the transfer of proton led to low performance. • Semi-continuous anolyte circulation enhanced the transfer of electron and proton. • Enrichment of electroactive and methanogenic microorganism occurred. CO 2 bioelectromethanosynthesis represents a promising strategy for the capture and utilization of CO 2. In such process, the continuous generation of electron (e-) and proton (H+) in anodic oxidation are of prime importance for the efficient cathodic CO 2 electroreduction and process stability. Proton transfer, however, is very easy to be hindered due to the fouling of proton exchange membrane (PEM). In this study, an artificial channel in microbial electrolysis cell (MEC) was proposed to strengthen the transport of protons from anodic to cathodic compartment, and H+-rich anolyte was semi-continuously circulated to the cathodic chamber to provide protons for CO 2 electroreduction. The results indicated that the daily CH 4 yield in cathode with anolyte circulation (18.5 mL/d·L-reactor) was 5.4-fold higher than that without circulation (2.9 mL/d·L-reactor). Meanwhile, efficient anodic biodegradation of organic components was observed with COD, proteins and polysaccharides removal of up to 95.6 ± 1.9%, 96.3 ± 3.7% and 99.1 ± 0.2% respectively, which supplied a continuous e-/H+ donor for CO 2 electroconversion. 16S rRNA gene pyrosequencing analysis identified a large number of proteins-utilizing Bacteroidetes (14.11%) and polysaccharides-consuming Thermotogae (18.49%) in anodic biofilm, conductive to the biodegradation of organic components. Moreover, a high abundance of Methanobacterium (81.07%) was detected to prevail in cathodic biofilm, demonstrating the occurrence of highly enhanced CH 4 bioelectrosysthesis. The syntrophic and symbiotic relationship was established in the dual-bioelectrode system, creating a beneficial environment and an energy-efficient approach for biowaste refinery and CO 2 electromethanosynthesis. [ABSTRACT FROM AUTHOR]

[Display omitted] • A uniform appearance is achieved by the introduction of ultrasound. • Ultrasound stimulates the formation of an amorphous Ca, P, Cu and O-rich layer. • Ultrasound is beneficial for corrosion and biological properties of the coating. To achieve a uniform surface layer with enhanced corrosion resistance, antibacterial capability and cytocompatibility on the titanium (Ti)-based orthopaedic implant, ultrasound-auxiliary micro-arc oxidation (UMAO) was carried out on Ti substrate to fabricate a Cu-incorporated TiO 2 coating. Instead of the co-existence of central brown area and peripheral black area in the Cu-incorporated TiO 2 coating fabricated by conventional micro-arc oxidation, a uniform brownish appearance could be achieved after the introduction of ultrasonic vibration (UV). The introduction of UV also significantly modifies the elemental composition, phase component and chemical configuration of the coating, which exhibits a bi-layered structure with the porous TiO 2 as the inner layer and the amorphous Ca, P, O and Cu component as the outer layer. Finally, electrochemical measurement and in vitro biological tests indicate that the introduction of UV is conducive to corrosion resistance, antibacterial capability and cytocompatibility of the Cu-incorporated TiO 2 coating. [ABSTRACT FROM AUTHOR]

Surfaces with desirable cytocompatibility and bactericidal ability are favoured for orthopaedic implants to stimulate osteogenic activity and to prevent implant-associated infection. In this work, we creatively introduce ultrasonic vibration (UV) to micro-arc oxidation (MAO) process and explore its influence on the microstructure, corrosion property and biological responses of Zn-modified TiO 2 coating. With the introduction of UV, a uniform surface layer with homogeneously-distributed clusters could be produced as the outer layer, which possesses a fusion band with the underlying TiO 2. The microstructural modification associated with UV results in the enhanced corrosion resistance, increased adhesive strength and improved biological performances of the resultant coating relative to that with the absence of UV. Hence, the ultrasonic auxiliary micro-arc oxidation (UMAO) is regarded as a promising surface modification method to produce Ti-based orthopaedic implants of high quality. [Display omitted] • A uniform appearance is achieved by ultrasound-auxiliary micro-arc oxidation. • A fusion band enhance the adhesive strength of the coating. • Ultrasonic action benefits corrosion resistance and biological performance. • In vivo biocompatibility of Zn-modified TiO 2 coating is demonstrated. [ABSTRACT FROM AUTHOR]

In this work, a Mn-incorporated Ca-P/TiO 2 composite coating was produced through the facile one-step micro-arc oxidation (MAO) method. It is revealed that only when the concentration of Na 2 Mn-EDTA reaches 0.02 mol/L, the Ca-P phase could form on Mn-incorporated TiO 2 coating, which is associated with the combined effect of EDTA complex and Mn species. The Ca-P phase is amorphous, which may contain hydroxyapatite phases whereas the underlying Mn-incorporated TiO 2 coating contains two separate layers, including the Mn-rich outer layer and Mn-depleted inner layer. The biological investigation of the Mn-incorporated Ca-P/TiO 2 composite coating suggests that it exhibits desirable osteogenesis with certain capability to inhibit the growth of S. aureus bacteria. Hence, a promising composite coating with superior bone formability could be produced using the one-step micro-arc oxidation method in the electrolyte containing Na 2 Mn-EDTA. Unlabelled Image • A Mn-incorporated Ca-P/TiO 2 composite coating could be successfully produced through the micro-arc oxidation method. • The outer Ca-P is amorphous whereas the inner TiO 2 contains two layers with different Mn contents. • Ca-P layer forms only when the concentration of Na 2 Mn-EDTA in the electrolyte reaches at least 0.02 mol/L. • The composite coating exhibits desirable corrosion resistance and bone formability with certain antibacterial ability. [ABSTRACT FROM AUTHOR]

• Potential of combined FNA and electrolysis for sludge disintegration was assessed. • Combined process improved the liberation of particulate to soluble fraction. • Methanogenesis was inhibited due to the toxicity of FNA and its derivatives. • Increased solubilization of organics does not always improve methane production. Free nitrous acid based pretreatments are novel and effective chemical strategies for enhancing waste activated sludge solubilization. In this study, the synergetic effects of the combined free nitrous acid and electrochemical pretreatment on sludge solubilization and subsequent methane productivity were evaluated. The results indicated that pretreatment with 10 V plus 14.17 mg N/L substantially enhanced sludge solubilization, with the highest soluble chemical oxygen demand concentration of 3296.7 mg/L, 25.6-time higher than that without pretreatment (128.9 mg/L). Due to the potential toxicity of NO 2 − and NO 3 − to microorganisms and its bioprocesses, the methane production of sludge pretreated by free nitrous acid was significantly deteriorated. The maximum methane yield (152.0 ± 9.6 mL/g-VS added) was observed at 10 V pretreatment alone, only 1.7% higher than that of the control (149.4 ± 1.6 mL/g-VS added). Combined pretreatment indeed enhances the sludge solubilization and hydrolysis, but does not always induce an improved anaerobic digestion efficiency. [ABSTRACT FROM AUTHOR]

• Metabolic behaviour depended upon the characteristics of petrochemical wastewaters. • The highest methane yield of 305.9 ± 2.7 mL/g-COD was achieved by PTA wastewater. • Modified Gompertz model was used to simulate biodegradation kinetics. • Toxic substances led to the cells lysis and inhibited methane production. • Wastewaters with high biodegradability were more suitable for anaerobic treatment. Petrochemical wastewaters treatment represents a serious challenge due to the high toxicity and complex chemical components. In this study, the biodegradability, mineralization behaviors and methane productivity of eight different types of petrochemical wastewaters were evaluated in series of semi-continuous bioreactors. Methane production strongly depended on the characteristics of wastewaters and chemical constituents. The highest methane yield of 305.9 ± 2.7 mL/g-COD was achieved by purified terephthalic acid wastewater, followed by ethylene glycol, polyester, etc. Comparatively, one-step-SCN− wastewater produced the lowest methane yield (4.7 ± 0.7 mL/g-COD) owing to high toxicity and low biodegradability. Modified Gompertz model confirmed that purified terephthalic acid, ethylene glycol and polyester wastewaters had a short lag-phase of 1.2, 1.7 and 0.2 days, respectively. Nonetheless, the formation of by-products such as proteins, polysaccharides and ammonia nitrogen throughout anaerobic digestion reflected the high activity of anaerobic microorganisms, confirming the technical feasibility of anaerobic biotechnology in treating petrochemical wastewaters. [ABSTRACT FROM AUTHOR]

• The pyrolysis characteristics and kinetics of sludge were analyzed by using TG-DSC-FTIR. • The yields of syngas and bio-oil were investigated with tubular pyrolysis system. • The microstructure of bio-char and the composition of bio-oil were deeply explored. • Pre-dewatered sewage sludge can be effectively converted into biofuel and porous material. The pyrolysis characteristics and kinetics of pre-dried dewatered sewage sludge under different heating rates (10, 20, and 30 °C/min) were investigated by thermogravimetric analyzer-fourier transform infrared analysis (TG-FTIR) and differential scanning calorimetry (DSC), and a heated tubular reactor. The thermal analysis results showed that four weight loss zones (<165, 165–400, 400–600, and >600 °C) were observed in TG curve, and a higher heating rate led to the increase of the maximum devolatilization rate and the higher temperature corresponding to the peak. The activation energy of different heating rate (10, 20, and 30 °C/min) was 70.0, 60.6 and 65.0 kJ/mol, respectively. The FTIR analysis of gaseous products indicated the concentrations of CO 2 and CO increased steadily with the increased heating rate, while the concentration of CH 4 first increased then decreased. Moreover, the yield of gaseous products and bio-oil increased with the increasing of the heating rate. Finally, the surface structure of chars and the chemical properties of bio-oil obtained were characterized using nitrogen adsorption, scanning electron microscopy, elemental analysis and gas chromatography–mass spectrometry. Overall, the results highlighted that pre-dried dewatered sewage sludge can be effectively converted into biofuel and porous material. [ABSTRACT FROM AUTHOR]

Background: Heavy menstrual bleeding (HMB) has been shown to have a profound negative impact on women's quality of life and lead to increases in health care costs; however, data on HMB among Chinese population is still rather limited. The present study therefore aimed to determine the current prevalence and risk factors of subjectively experienced HMB in a community sample of Chinese reproductive-age women, and to evaluate its effect on daily life.Methods: We conducted a questionnaire survey in 2356 women aged 18-50 years living in Beijing, China, from October 2014-July 2015. A multivariate logistic regression model was used to identify risk factors for HMB.Results: Overall, 429 women experienced HMB, giving a prevalence of 18.2%. Risk factors associated with HMB included uterine fibroids (adjusted odds ratio [OR] =2.12, 95% confidence interval [CI] = 1.42-3.16, P < 0.001) and multiple abortions (≥3) (adjusted OR = 3.44, 95% CI = 1.82-6.49, P < 0.001). Moreover, women in the younger age groups (≤24 and 25-29 years) showed higher risks for HMB, and those who drink regularly were more likely to report heavy periods compared with never drinkers (adjusted OR = 2.78, 95% CI = 1.20-6.46, P = 0.017). In general, women experiencing HMB felt more practical discomforts and limited life activities while only 81 (18.9%) of them had sought health care for their heavy bleeding.Conclusions: HMB was highly prevalent among Chinese women and those reporting heavy periods suffered from greater menstrual interference with daily lives. More information and health education programs are urgently needed to raise awareness of the consequences of HMB, encourage women to seek medical assistance and thus improve their quality of life. [ABSTRACT FROM AUTHOR]

Bound extracellular polymeric substances (EPS) are complex, high-molecular-weight polymer mixtures that play a critical role in pore clogging, foulants adhesion, and fouling layer formation during membrane filtration, owing to their adhesive properties and gelation tendencies. In this study, a novel electrochemical anaerobic membrane bioreactor (EC-AnMBR) was constructed to investigate the effect of sludge bound-EPS solubilization on methane bioconversion and membrane fouling mitigation. During the 150-days' operation, the EC-AnMBR demonstrated remarkable performance, characterized by an exceptionally low fouling rate (transmembrane pressure (TMP) < 4.0 kPa) and high-quality effluent (COD removal > 98.2 %, protein removal > 97.7 %, and polysaccharide removal > 98.5 %). The highest methane productivity was up to 38.0 ± 3.1 mL/L reactor /d at the applied voltage of 0.8 V with bound-EPS solubilization, 107.6 % higher than that of the control stage (18.3 ± 2.4 mL/L reactor /d). Morphological and multiplex fluorescence labeling analyses revealed higher fluorescence intensities of proteins, polysaccharides, total cells and lipids on the surface of the fouling layer. In contrast, the interior exhibited increased compression density and reduced activity, likely attributable to compression effect. Under the synergistic influence of the electric field and bound-EPS solubilization, biomass characteristics exhibited a reduced propensity for membrane fouling. Furthermore, the bio-electrochemical regulation enhanced the electroactivity of microbial aggregates and enriched functional microorganisms, thereby promoting biofilm growth and direct interspecies electron transfer. Additionally, the potential hydrogenotrophic and methylotrophic methanogenesis pathways were enhanced at the cathode and anode surfaces, thereby increasing CH₄ productivity. The random forest-based machine learning model analyzed the nonlinear contributions of EPS characteristics on methane productivity and TMP values, achieving R² values of 0.879 and 0.848, respectively. Shapley additive explanations (SHAP) analysis indicated that S-EPS PS and S-EPS PN were the most critical factors affecting CH₄ productivity and membrane fouling, respectively. Partial dependence plot analysis further verified the marginal and interaction effects of different EPS layers on these outcomes. By combining continuous operation with interpretable machine learning algorithms, this study unveils the intricate impacts of EPS characteristics on methane productivity and membrane fouling behaviors, and provides new insights into sludge bound-EPS solubilization in EC-AnMBR., Competing Interests: Declaration of competing interest All of the authors declare that they have no conflict of interest.., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Background: Acute myeloid leukemia (AML) is characterized by high heterogeneity, poor long-term survival, and a propensity for relapse. Exceptional efficacy in treating recurrent or refractory B-lymphoid malignancies has been demonstrated by Chimeric antigen receptor T cells (CAR-T cells). Given the therapeutic potential of targeting both CD33 and C-type lectin-like molecule-1 (CLL1) in AML, the development of a dual-targeting CD33-CLL1 CAR-T cells assumes significant importance., Materials and Methods: The expressions of CD33 and CLL-1 antigens in peripheral blood cells and bone marrow cells from AML patients was assessed. Subsequently, a Chimeric Antigen Receptor (CAR) incorporating a dual-specific single-chain variable fragment targeting CLL1 and CD33 (CD33-CLL1-CAR-T) was engineered. The anti-tumor efficacy and potential side effects of CD33-CLL1-CAR-T cells were comprehensively investigated in both in vitro and in vivo settings., Results: The constructed tandem CD33-CLL1 CAR-T exhibited potent cytotoxicity against leukemia cell lines and human primary AML cells in vitro. Co-cultivation of AML blasts with CD33-CLL1-CAR-T cells resulted in effective proliferation and the secretion of substantial quantities of GM-CSF and IFN-γ. Importantly, the impact of CD33-CLL1-CAR-T cells on normal hematopoietic stem cells was minimal, ensuring safety in vivo mouse models. Notably, significant anti-leukemic activity was observed in the mouse model, with CD33-CLL1-CAR-T cells leading to tumor eradication and prolonged survival., Discussion: The tandem CD33-CLL1 CAR-T cells not only efficiently eliminated AML blasts but also exhibited low cytotoxicity toward normal hematopoietic stem cells (HSCs). These findings underscore the potential clinical applicability of the tandem CD33-CLL1 CAR-T cells as an effective and safe treatment strategy for AML, representing a noteworthy advancement in the field of CAR-T cells therapy.

Despite the vital roles of Fe 0 /biochar composites in the Fenton-like systems for eliminating pollutants that have been recognized, the contributions of persistent free radicals (PFRs) of carbon-based materials are typically overlooked. In this study, the high-PFR-containing biochar nanoiron composites were prepared (nZVI/500), and the in situ generation of hydroxyl radicals (·OH) and degradation of p-nitrophenol (PNP) were investigated. The results showed that nZVI/500 could effectively remove PNP in solution within the pH range of 3-8. Quantitative experiments of ·OH presented that, compared with low PFRs-containing composites, nZVI/500 could generate 64.6 µM ·OH in 60 min without any extra energy consumption. Mechanistic studies revealed that (1) both PFRs and Fe 0 are able to utilize dissolved oxygen to generate H 2 O 2 in situ; (2) PFRs can promote the cycling of Fe 3+ /Fe 2+ in the system due to their strong electron exchange ability; and (3) PFRs directly transfer electrons to H 2 O 2 ; therefore, the presence of PFRs accelerates the generation of ·OH in the system and facilitates the removal of PNP. This study provides an important theoretical basis and technical reference for expanding the application of PFR-rich carbon-based materials to remove environmental pollutants., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

High water and pharmaceutical and care products (PPCPs) bounded in sludge flocs limit its utilization and disposal. The advanced oxidation process of perxymonosulfate (PMS) catalyzed by iron salts has been widely used in sludge conditioning. In this study, two iron-rich minerals pyrite and siderite were proposed to enhance sludge dewatering performance and remove the target contaminant of triclosan (TCS). The permanent release of Fe 2+ in the activation of PMS made siderite more effective in enhancing sludge dewater with capillary suction time (CST) diminishing by 60.5 %, specific resistance to filtration (SRF) decreasing by 79.2 %, and bound water content (BWC) dropping from 37.1 % to 2.6 % at siderite/PMS dosages of 0.36/0.20 mmol/g-TSS after 20 min of pretreatment. Pyrite/PMS performed slightly inferior under the same conditions and the corresponding CST and SRF decreased by 51.5 % and 71.8 % while the BWC only declined to 17.8 %. Rheological characterization was employed to elucidate the changes in sludge dewatering performance, with siderite/PMS treated sludge showing a 48.3 % reduction in thixotropy, higher than 28.4 % of pyrite/PMS. Oscillation and creep tests further demonstrated the significantly weakened viscoelastic behavior of the sludge by siderite/PMS pretreatment. For TCS mineralization removal, siderite/PMS achieved a high removal efficiency of 43.9 %, in comparison with 39.9 % for pyrite/PMS. The reduction in the sludge solids phase contributed the most to the TCS removal. Free radical quenching assays and EPR spectroscopy showed that both siderite/PMS and pyrite/PMS produced SO 4 - ·  and ·OH, with the latter acting as the major radicals. Besides, the dosage of free radicals generated from siderite/PMS exhibited a lower time-dependence, which also allowed it to outperform in destroying EPS matrix, neutralizing the negative Zeta potential of sludge flocs, and mineralizing macromolecular organic matter., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Introduction: Variability in microbial residues within soil aggregates are becoming progressively essential to the nutritive and sustainability of soils, and are therefore broadly regarded as an indispensable part of soil organic matter. It is unexplored how the widespread implementation of microbial fertilisers in agricultural production impacts soil organic nutrients, in particular the microbial residue fraction., Methods: We performed a three-year field experiment to verify the distinct impacts of microbial and organic fertilizers on carbon accumulation in soil microbial leftovers among aggregate fractions., Results: Microbial residual carbon was shown to decrease insignificantly during the application of microbial fertilizer and to rise marginally afterwards with the utilization of organic fertilizer. However, the combined effects of the two fertilizers had substantial impacts on the accumulation of microbial residual carbon. Changes in the structure of the fungi and bacteria shown in this study have implications for the short-term potential of microbial fertilizer shortages to permanent soil carbon sequestration. Additionally, our findings revealed variations in microbial residue accumulation across the microbial fertilizers, with Azotobacter chroococcum fertilizer being preferable to Bacillus mucilaginosus fertilizer due to its higher efficiency. In this scenario of nutrient addition, fungal residues may serve as the primary binding component or focal point for the production of new microaggregates, since the quantity of SOC provided by fungal residues increased while that supplied by bacterial residues decreased., Discussion: Our findings collectively suggested that the mechanisms behind the observed bacterial and fungal MRC (microbial residue carbon) responses to microbial fertilizer or organic fertilizer in bamboo forest soils are likely to be distinct. The application of microbial fertilizers for a limited duration led to a decline soil stable carbon pool, potentially influencing the regulation of soil nutrients in such hilly bamboo forests., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Cai, Long, Li, Cao, Wang, Zhao, Ren, Zhao, Huang, Lu, Hu and Xu.)

Congenital thrombotic thrombocytopenic purpura (TTP) is a rare autosomal recessive genetic disorder caused by mutations in the ADAMTS13 gene. Approximately 200 mutations of the ADAMTS-13 gene have been identified, although only a few have been characterized through in vitro expression studies. We conducted an investigation on a male congenital TTP patient with reduced plasma levels of ADAMTS13 activity. DNA sequence analysis revealed two mutations on chromosome 9 ( 1.9q34.2 ) in the patient's ADAMTS13 gene. One mutation was a non-synonymous mutation ( exon 5: c.A530G: p.Y177C ), while the other was a nonsense mutation ( exon 21: c.G2651A: p.W884X ). Both mutations were found to be heterozygous. The patient's parents had no history of thrombocytopenia or neurological symptoms. DNA sequence analysis showed the patient's father was a heterozygote for the nonsense mutation of the ADAMTS13 gene ( exon 21: c.G2651A: p.W884X ), while the mother was a heterozygote for the non-synonymous mutation of the ADAMTS13 gene (exon 5: c.A530G: p.Y177C ). To investigate the mechanism behind ADAMTS13 deficiency in this patient, wild type (WT), ADAMTS13 p.Y177C , and ADAMTS13 p.W884X were transiently expressed in 293-6E cells. Expression studies revealed a significant reduction in enzyme activity and secretion, although the protease was detected within the cells. The 3D structures of the natural and mutated ADAMTS-13 proteins were partially reconstructed using the Phyre2 web server. The mutation that replaces the tyrosine residue at amino acid position 177 with cysteine may result in decreased steric hindrance and a looser structure. This mutation affects the binding of calcium ions and the secretion of the enzyme from intracellular to extracellular compartments.

The disintegration of anaerobic sludge and blockage of membrane pores has impeded the practical application of anaerobic membrane bioreactor (AnMBR) in treating methanolic wastewater. In this study, bioelectrochemical system (BES) was integrated into AnMBR to alleviate sludge dispersion and membrane fouling as well as enhance bioconversion of methanol. Bioelectrochemical regulation effect induced by BES enhanced methane production rate from 4.94 ± 0.52 to 5.39 ± 0.37 L/L reactor /d by accelerating the enrichment of electroactive microorganisms and the agglomeration of anaerobic sludge via the adhesive and chemical bonding force. 16 S rRNA gene high-throughput sequencing demonstrated that bioelectrochemical stimulation had modified the metabolic pathways by regulating the key functional microbial communities. Methanogenesis via the common methylotrophic Methanomethylovorans was partially substituted by the hydrogenotrophic Candidatus&#95;Methanofastidiosum, etc. The metabolic behaviors of methanol are bioelectrochemistry-dependent, and controlling external voltage is thus an effective strategy for ensuring robust electron transfer, low membrane fouling, and long-term process stability., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier Ltd.)

Background: Atherosclerotic cardiovascular disease (ASCVD) remains the leading cause of death and disability both in U.S. and worldwide. Antioxidants have been proved critical in mitigating the development of atherosclerosis. This study aimed to investigate the associations between composite dietary antioxidant index (CDAI) and estimated 10-year ASCVD risk among U.S. adults., Methods: Data extracted from the National Health and Nutrition Examination Survey were analyzed. A total of 10,984 adults aged 18 years and above were included in this study. CDAI was calculated based on the dietary intake reported in their 24-h recall interviews. The estimated 10-year ASCVD risk was calculated via Pooled Cohort Equations (PCE)., Results: After adjusting potential confounders, it was indicated that CDAI score was negatively correlated with 10-year ASCVD risk (OR 0.97, 95% CI 0.95-0.99). Stratify CDAI score by quartile, results showed that participants in the second, third, and fourth quartiles had lower ASCVD odds ratio (Q2: OR 0.87, 95% CI 0.69-1.09; Q3: OR 0.78, 95% CI 0.62-0.98; Q4: OR 0.74, 95% CI 0.59-0.94) than those in the first quartile (Q1, lowest CDAI score group), which was confirmed by the trend test as well ( p  < 0.05). Subgroup analyses stratified by sex, age, race/ethnicity, and smoking status did not show significant effect modification., Conclusion: Higher dietary antioxidants intake is associated with lower ASCVD risk among U.S. adults, for which policymakers and healthcare professionals may consider increasing the consumption of antioxidant-rich foods as a preventive strategy for ASCVD., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Zhang, Lu, Wu, Ni, Xu, Wu, Lu, Feng and Jin.)

The combination technique of pre-ozonation and bioaugmentation is promising for remediating benzo[a]pyrene (BaP)-contaminated soil. However, little is known about the effect of coupling remediation on the soil biotoxicity, soil respiration, enzyme activity, microbial community structure, and microbial in the process of remediation. This study developed two coupling remediation strategies (pre-ozonation coupled with bioaugmentation by addition of polycyclic aromatic hydrocarbons (PAHs) specific degrading bacteria or activated sludge), compared with sole ozonation and sole bioaugmentation, to improve degradation of BaP and recovery of soil microbial activity and community structure. Results showed that the higher removal efficiency of BaP (92.69-93.19%) was found in coupling remediation, compared with sole bioaugmentation (17.71-23.28%). Meanwhile, coupling remediation significantly reduced the soil biological toxicity, promoted the rebound of microbial counts and activity, and recovered the species numbers and microbial community diversity, compared with sole ozonation and sole bioaugmentation. Besides, it was feasible to replace microbial screening with activated sludge, and coupling remediation by addition of activated sludge was more conducive to the recovery of soil microbial communities and diversity. This work provides a strategy of pre-ozonation coupled with bioaugmentation to further degrade BaP in soil by promoting the rebound of microbial counts and activity, as well as the recovery of species numbers and microbial community diversity., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Purified terephthalic acid (PTA) wastewater with properties of poor biodegradation and high toxicity is produced from refining and synthesis of petrochemical products. In this study, a lab-scale hollow fiber membrane bioreactor (HF-AnMBR) fed with synthetic PTA wastewater was operated over 200 days with stepwise decreased hydraulic retention time (HRT) to investigate the long-term performance, membrane fouling mechanism and microbial community evolution. Results showed that a stable chemical oxygen demand (COD) removal rate of 65.8 ± 4.1% was achieved at organic loading rate of 3.1 ± 0.3 g-COD/L-reactor/d and HRT 24 h, under which the methane production rate reached 0.33 ± 0.02 L/L-reactor/d. Further shortening HRT, however, led to the decreased COD removal efficiency and low methane bioconversion. A mild membrane fouling occurred due to the production of colloidal biopolymers and the interaction between increased colloidal substances secreted/cracked by microorganisms and membrane interface. Further 16S rRNA analysis indicated that microbial diversity and richness had changed with the variation of HRT while Methanosaeta, and Methanolinea species were always the dominant methanogens responsible for methane production. The results verify that HF-AnMBR is an alternative technology for PTA wastewater treatment along with energy harvesting, and provide a new avenue toward sustainable petrochemical wastewater management., (Copyright © 2021 Elsevier B.V. All rights reserved.)

The potential of disordered mesoporous carbon (DMC) as catalyst of peroxydisulfate (PDS) to improve sludge solubilization and methane production was investigated. Results showed that DMC activated PDS (DMC/PDS) to produce sulfate radicals (SO 4 - ), facilitating cells rupture and sludge matrix dissociation by degrading the carbonyl and amide groups in organic biopolymers (especially proteins, polysaccharides and humus). At the optimal DMC/PDS dosage of 0.04/1.2 g-mmol/g-VS, SCOD was increased from initial 294.0 to 681.5 mg/L, with the methane production rate of 12.6 mL/g-VS/day. Moreover, DMC could serve as electron mediator to accelerate electron transfer of microorganisms, building a more robust anaerobic metabolic environment. Modelling analysis further demonstrated the crucial role of DMC/PDS pretreatment in biological degradation and methane productivity. This study indicated that DMC/PDS pretreatment can prominently enhance the release of soluble substances and methane production, aiding the utilization of PDS oxidation technology for improving anaerobic bioconversion of sludge., (Copyright © 2021. Published by Elsevier Ltd.)

Microbial electrolysis cell (MEC) was integrated into conventional anaerobic digestion (AD) system (i.e. MEC-AD) to electrochemically regulate the co-fermentation of food waste (FW) and sewage sludge (SS). Two anaerobic systems (i.e. MEC-AD, and single AD) were operated in parallel to explore the potential stimulation of electrical regulation in metabolic behaviors of FW and SS and subsequent biomethane production. The highest accumulative methane yield was achieved at an applied voltage of 0.4 V and the FW and SS ratio of 0.2:0.8, increasing by 2.8-fold than those in AD. The combined MEC-AD system mitigated N 2 O emission and considerably improved ammonia removal and the dewaterability of digestate, in contrast to AD. Scanning electron microscope (SEM) visualized the presence of a large number of rod-like and cocci-like electroactive microbes on the electrode surface. Electrical regulation stimulated the self-growth and proliferation of typical Methanobacterium and Methanosaeta, accordingly contributing to biomethane production greatly., (Copyright © 2019 Elsevier Ltd. All rights reserved.)