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Antineoplásicos , Humanos , Antineoplásicos/farmacología , Antineoplásicos/química , Antineoplásicos/síntesis química , Diseño Asistido por Computadora , Relación Dosis-Respuesta a Droga , Diseño de Fármacos , Ensayos de Selección de Medicamentos Antitumorales , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/síntesis química , Colorantes Fluorescentes/química , Colorantes Fluorescentes/síntesis química , Colorantes Fluorescentes/farmacología , N-Metiltransferasa de Histona-Lisina/antagonistas & inhibidores , N-Metiltransferasa de Histona-Lisina/metabolismo , Estructura Molecular , Relación Estructura-Actividad , Mutaciones Letales Sintéticas , Metionina Adenosiltransferasa/antagonistas & inhibidores , Metionina Adenosiltransferasa/química , Metionina Adenosiltransferasa/metabolismoRESUMEN
Dynamic assessment of cerebral blood flow (CBF) is crucial for guiding personalized management and treatment strategies, and improving the prognosis of stroke. However, a safe, reliable, and effective method for dynamic CBF evaluation is currently lacking in clinical practice. In this study, we developed a CBF monitoring system utilizing electromagnetic coupling sensing (ECS). This system detects variations in brain conductivity and dielectric constant by identifying the resonant frequency (RF) in an equivalent circuit containing both magnetic induction and electrical coupling. We evaluated the performance of the system using a self-made physical model of blood vessel pulsation to test pulsatile CBF. Additionally, we recruited 29 healthy volunteers to monitor cerebral oxygen (CO), cerebral blood flow velocity (CBFV) data and RF data before and after caffeine consumption. We analyzed RF and CBFV trends during immediate responses to abnormal intracranial blood supply, induced by changes in vascular stiffness, and compared them with CO data. Furthermore, we explored a method of dynamically assessing the overall level of CBF by leveraging image feature analysis. Experimental testing substantiates that this system provides a detection range and depth enhanced by three to four times compared to conventional electromagnetic detection techniques, thereby comprehensively covering the principal intracranial blood supply areas. And the system effectively captures CBF responses under different intravascular pressure stimulations. In healthy volunteers, as cerebral vascular stiffness increases and CO decreases due to caffeine intake, the RF pulsation amplitude diminishes progressively. Upon extraction and selection of image features, widely used machine learning algorithms exhibit commendable performance in classifying overall CBF levels. These results highlight that our proposed methodology, predicated on ECS and image feature analysis, enables the capture of immediate responses of abnormal intracranial blood supply triggered by alterations in vascular stiffness. Moreover, it provides an accurate diagnosis of the overall CBF level under varying physiological conditions.
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Single cell oil (SCO) prepared from biodiesel-derived crude glycerol (BCG) and lignocellulosic biomass (LCB) via oleaginous yeasts is an intriguing alternative precursor of biodiesel. Here, a novel strategy combining alkaline BCG pretreated corn stover and dilute acid pretreated water hyacinth for SCO overproduction was developed. The mixed pretreatment liquors (MPLs) were naturally neutralized and adjusted to a proper carbon-to-nitrogen ratio beneficial for SCO overproduction by Cutaneotrichosporon oleaginosum. The toxicity of inhibitors was relieved by dilution detoxification. The enzymatic hydrolysate of solid fractions was suitable for SCO production either separately or simultaneously with MPLs. Fed-batch fermentation of the MPLs resulted in high cell mass, SCO content, and SCO titer of 80.7 g/L, 75.7 %, and 61.1 g/L, respectively. The fatty acid profiles of SCOs implied high-quality biodiesel characteristics. This study offers a novel BCG&LCB-to-SCO route integrating BCG-based pretreatment and BCG/LCB hydrolysates co-utilization, which provides a cost-effective technical route for micro-biodiesel production.
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Basidiomycota , Eichhornia , Glicerol , Biocombustibles , Zea mays , Lípidos , Levaduras , Fermentación , Ácidos , BiomasaRESUMEN
Covalent organic frameworks (COFs) with flexible periodic skeletons and ordered nanoporous structures have attracted much attention as potential candidate electrode materials for green energy storage and efficient seawater desalination. Further improving the intrinsic electronic conductivity and releasing porosity of COF-based materials is a necessary strategy to improve their electrochemical performance. Herein, the employed graphene as the conductive substrate to in situ grow 2D redox-active COF (TFPDQ-COF) with redox activity under solvent-free conditions to prepare TFPDQ-COF/graphene (TFPDQGO) nanohybrids and explores their application in both supercapacitor and hybrid capacitive deionization (HCDI). By optimizing the hybridization ratio, TFPDQGO exhibits a large specific capacitance of 429.0 F g-1 due to the synergistic effect of the charge transport highway provided by the graphene layers and the abundant redox-active centers contained in the COF skeleton, and the assembled TFPDQGO//activated carbon (AC) asymmetric supercapacitor possesses a high energy output of 59.4 Wh kg-1 at a power density of 950 W kg-1 and good cycling life. Furthermore, the maximum salt adsorption capacity (SAC) of 58.4 mg g-1 and stable regeneration performance is attained for TFPDQGO-based HCDI. This study highlights the new opportunities of COF-based hybrid materials acting as high-performance supercapacitor and HCDI electrode materials.
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Currently, the development of economical and effective non-noble metal electrocatalysts is vital for advancing hydrogen evolution reaction (HER) and enabling its widespread applications. The customizable pore structure and enormous surface area of metal-organic frameworks (MOFs) have made them to become promising non-noble metal electrocatalysts for HER. However, MOFs have some challenges, including low conductivity and instability, which can result in them having high overpotentials and slow reaction kinetics in electrocatalytic processes. In this work, we present an innovative approach for synthesizing cost-effective and high-efficient Zr-MOF-derived pH-universal electrocatalysts for HER. It entails creating the interfaces of the electrocatalysts with suitable proportions of phosphide nanostructures. Zr-MOF/Ni2P@nickel foam (NF) electrodes with interface regulated by Ni2P nanostructures were successfully developed for high-efficient pH-universal HER electrocatalysts. The presence of Ni2P nanostructures with abundant active sites at the Zr-MOFs@NF interfaces boosted the electronic conductivity and local charge density of the hybrid electrocatalysts. This helped to improve their reaction kinetics and electrocatalytic activity. By optimizing the Ni2P amount, Zr-MOF/Ni2P@NF demonstrated impressive stability and superior HER activities, with a low overpotential of 149 mV (acidic electrolytes) and 143 mV (alkaline electrolytes) at 10 mA cm-2. The proven strategy in this work can be expanded to many types of MOF-based materials for wider practical applications.
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Spent biomass from agricultural and forestry industries are substantial low-cost carbon source for reducing the input of microbial lipid production. Herein, the components of the vineyard winter prunings (VWPs) from 40 grape cultivars were analyzed. The VWPs contained (w/w) cellulose ranged from 24.8% to 32.4%, hemicellulose 9.6% to 13.8%, lignin 23.7% to 32.4%. The VWPs from Cabernet Sauvignon was processed with the alkali-methanol pretreatment, and 95.8% of the sugars was released from the regenerated VWPs after enzymatic hydrolysis. The hydrolysates from the regenerated VWPs was suitable for lipid production without further treatment as a lipid content of 59% could be achieved with Cryptococcus curvatus. The regenerated VWPs was also used for lipid production via simultaneous saccharification and fermentation (SSF), which led to a lipid yield of 0.088 g/g raw VWPs, 0.126 g/g regenerated VWPs and 0.185 g/g from the reducing sugars. This work demonstrated that the VWPs can be explored for co-production of microbial lipids.
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Cryptococcus , Lípidos , Granjas , Fermentación , Azúcares , BiomasaRESUMEN
Pretreatment is a prerequisite to tackle the issue of biomass recalcitrance, which is the major hindrance of lignocellulose-to-sugars routes. In the present study, a novel combination of dilute sulfuric acid (dilute-H2SO4) with Tween 80 pretreatment of corn stover (CS) was developed to significantly enhance the enzyme digestibility. Strong synergistic effects of H2SO4 and Tween 80 for simultaneously eliminating hemicellulose and lignin and significantly promoting saccharification yield were observed. A response surface optimization realized the maximum monomeric sugar yield of 95.06% at 120 °C for 1.4 h with 0.75 wt% of H2SO4 and 73.92 wt% of Tween 80. The excellent enzyme susceptibility of pretreated CS was explained by their physical and chemical characteristics via SEM, XRD, and FITR. The repeatedly recovered pretreatment liquor exerted highly-effective reusability in the subsequent pretreatments for at least four cycles. This strategy offers a highly-efficient and practical pretreatment strategy, which provides valuable information for the lignocellulose-to-sugars routes.
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Lignina , Polisorbatos , Zea mays , Hidrólisis , AzúcaresRESUMEN
The single-celled eukaryote Euplotes aediculatus was chosen to test and compare the toxic effects of Cu and CuO nanoparticles (NPs). The antioxidant enzymatic activity, morphological changes, and functional groups on the membrane were determined using spectrophotometry, microscopy, and Fourier transform infrared spectroscopy after NPs treatment. The toxicity of the NPs to cells was dose-dependent, and the 24 h-LC50 values of the CuNPs and CuONPs were 0.46 µg/L and 1.24 × 103 µg/L, respectively. These NPs increased the activities of superoxide dismutase, glutathione peroxidase, and catalase and destroyed the cell structure; moreover, the CuNPs were more toxic than the CuONPs. In addition to the higher enzymatic activity, CuNPs also caused nucleoli disappearance, chromatin condensation, and mitochondrial and pellicle damage. The oxidization of the functional groups of the membrane (PO2 - , C-O-C, and δ(COH) of carbohydrates) also confirmed the severe damage caused by CuNPs. Our study showed that oxidative stress and organelle destruction played important roles in the toxic effects of these NPs on this protozoan. Compared with other aquatic organisms, E. aediculatus can be considered a potential indicator at the preliminary stage of environmental pollution.
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Euplotes , Nanopartículas del Metal , Nanopartículas , Nanopartículas del Metal/toxicidad , Cobre , Estrés OxidativoRESUMEN
BACKGROUND: Resveratrol is a plant-derived phenylpropanoid with diverse biological activities and pharmacological applications. Plant-based extraction could not satisfy ever-increasing market demand, while chemical synthesis is impeded by the existence of toxic impurities. Microbial production of resveratrol offers a promising alternative to plant- and chemical-based processes. The non-conventional oleaginous yeast Rhodotorula toruloides is a potential workhorse for the production of resveratrol that endowed with an efficient and intrinsic bifunctional phenylalanine/tyrosine ammonia-lyase (RtPAL) and malonyl-CoA pool, which may facilitate the resveratrol synthesis when properly rewired. RESULTS: Resveratrol showed substantial stability and would not affect the R. toruloides growth during the yeast cultivation in flasks. The heterologus resveratrol biosynthesis pathway was established by introducing the 4-coumaroyl-CoA ligase (At4CL), and the stilbene synthase (VlSTS) from Arabidopsis thaliana and Vitis labrusca, respectively. Next, The resveratrol production was increased by 634% through employing the cinnamate-4-hydroxylase from A. thaliana (AtC4H), the fused protein At4CL::VlSTS, the cytochrome P450 reductase 2 from A. thaliana (AtATR2) and the endogenous cytochrome B5 of R. toruloides (RtCYB5). Then, the related endogenous pathways were optimized to affect a further 60% increase. Finally, the engineered strain produced a maximum titer of 125.2 mg/L resveratrol in YPD medium. CONCLUSION: The non-conventional oleaginous yeast R. toruloides was engineered for the first time to produce resveratrol. Protein fusion, co-factor channeling, and ARO4 and ARO7 overexpression were efficient for improving resveratrol production. The results demonstrated the potential of R. toruloides for resveratrol and other phenylpropanoids production.
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Arabidopsis , Rhodotorula , Ingeniería Metabólica/métodos , Resveratrol/metabolismo , Arabidopsis/genética , Rhodotorula/genética , Rhodotorula/metabolismo , Levaduras , PlantasRESUMEN
Highly integrated processes are crucial for the commercial success of microbial lipid production from low-cost substrates. Here, combination of simultaneous saccharification and fermentation (SSF) of corn stover with consolidated bioprocessing (CBP) of cassava starch by Lipomyces starkeyi was firstly developed as a novel strategy for lipid production. Starch was quickly hydrolyzed within 24 h by the amylolytic enzymes secreted by L. starkeyi to provide adequate fermentable sugars at the initial stage of culture, which eliminated the pre-hydrolysis step. More interestingly, synergistic effect for achieving higher lipid production by combined utilization of corn stover and cassava starch at relatively low enzyme dosage was realized, in comparison with the separate utilization of these two substrates. The fatty acid profiles indicated that lipid prepared by the combination strategy was suitable precursor for biodiesel production. The combined SSF&CBP strategy offers a simplified, highly-efficient, and economical route for co-valorization of low-cost substrates into lipids.
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Microplastics are widely distributed in the biogeochemical cycle driven by microbes. Their surface is enriched with unique microbial communities, called plastispheres. Various redox environments that exist widely in the natural environment can affect the microbial composition in the plastisphere and the fate of the microplastics. To explore the microbial community composition and construction mechanism on the surface of microplastics in typical redox environments, three microplastics, PHA (polyhydroxyalkanoates), PLA (polylactic acid), and PVC (polyvinyl chloride), were placed in five specific redox environments:aerobic, nitrate reduction, iron oxide reduction, sulfate reduction, and methane production. The culture experiment simulated the microcosm, which was inoculum by sludge. The results showed that microplastic factors affected 18.94% and 46.67% of the microbial communities on the plastisphere in taxonomy and phylogeny, respectively. Redox factors affected 31.04% and 90.00% of the microbial communities on the plastisphere in taxonomy and phylogeny, respectively. Compared with that in sludge, the microbial community richness and diversity were reduced on the three microplastics. The most apparent reduction was found on the plastisphere of more degradable PHA. At the same time, microbial communities on the refractory PLA and PVC surfaces remained similar. Anaerocolumna (26.44%) was the dominant genus on the surface of PHA microplastics, whereas microbes related to the redox reaction were less enriched. Clostridium_sensu_stricto_7 (15.49% and 11.87%) was the dominant strain on PLA and PVC microplastics, and the microbes related to the redox reaction were significantly enriched. Thus, characteristic microbes involved in the redox reaction will be enriched in the surface of refractory microplastics, and microplastics may affect the rate of biogeochemical cycling.
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Microbiota , Microplásticos , Oxidación-Reducción , Plásticos , Poliésteres , Cloruro de Polivinilo , Aguas del AlcantarilladoRESUMEN
Prospects for the use of manganites in various areas of modern technologies require comprehensive studies of their physical and chemical properties. La0.9Mn1.1O3 (LMO) ceramics have been synthesized at an annealing temperature tann of 1150 °C with further post-annealing at 1250, 1350, and 1450 °C. As tann increases, the structure symmetry changes, and both the crystallite size and chemical defects increase. The post-annealing, on one hand, leads to a dramatic reduction of the magnetocaloric effect (MCE) |-ΔSmaxM| from 3.50 to 0.75 J (kg K)-1 at 2 T and a Curie temperature TC from 227 to 113 K with increasing tann. On the other hand, an external hydrostatic high-pressure P works oppositely enhancing ferromagnetic interactions. The saturation of -ΔSmaxM and TC is already achieved at a relatively low P of ≈ 0.4 GPa. LMO-1150 exhibits the best magnetocaloric characteristics compared with other studied samples. Moreover, the electrochemical characteristics of the LMO materials as electrocatalysts for overall water splitting (OER process) and features of their transformation in different 0.5 M K2SO4, 0.5 M K2HPO4, and 0.1 M K2B4O7 electrolytes have been studied thoroughly. After electrocatalysis of LMO, the magnetization M decreases and TC remains, which makes it possible to control the depletion of electrodes and predict their working time based on the magnetic measurements. All samples show the best OER activity in the 0.5 M K2HPO4 media. The obtained results demonstrate the ways for controlling the MCE of LMO under changing internal and external conditions, and an evaluation of the possibilities for their OER applications in electrocatalysts.
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Flexible zinc-silver oxide (Zn-Ag2O) batteries have attracted extensive attention for comfortable wearable electronics owing to their stable output voltage, inherent safety, and environmental benignity. However, they suffer from inferior specific capacity and poor mechanical stability due to the low utilization of Ag2O cathodic material and weak interfacial adhesion of active material/substrate. Inspired by the nature of the tree root system, we develop an interface-engineered cathode, in which Ag2O nanoparticles are rooted on an Au, Ni co-modified filter paper substrate (CFP) through an electroless plating followed by an in situ electrochemical oxidation. The staggered-stacked Ag2O nanoparticles provide abundant electrochemically active sites and convenient ion diffusion paths, and the unique biological tree-root-like structure of the electrode material creates robust interlocking interfaces. A quasi-solid-state Zn-Ag2O battery assembled with a tree-root-like Ag2O/CFP cathode delivers a high areal specific capacity of 1.08 mAh cm-2 and long-term cycling durability with a capacity retention of 77.3% even after 100 cycles. Moreover, the device presents good mechanical stability under various flexural deformations, including bending, folding, and twisting, and exhibits minimal capacity changes after 1000 bending cycles. These findings suggest that the bio-inspired interface-engineered electrode structure is an efficient approach for developing flexible batteries with excellent electrochemical performance and mechanical properties.
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Suministros de Energía Eléctrica , Electrónica , Electrodos , ZincRESUMEN
Although many reports have demonstrated that nanoparticles can have a negative effect on aquatic organisms, the toxic effects on symbiotic organisms remain poorly understood. The present study conducts ultrastructure, enzyme activity, and transcriptomics to assess the toxic effects to the Paramecium bursaria-Chlorella symbiotic system from exposure to copper nanoparticles (CuNPs) for 24 h. We found that in both the host and symbiotic algae, CuNP exposure induced high reactive oxygen species level, which leads to oxidative damage and energy metabolism disorder. Moreover, transmission electron micrographs (TEMs) showed that the symbiotic algae in the cytoplasm of P. bursaria were enveloped in the digestive vacuole and digested, and the level of acid phosphatase activity increased significantly within 24 h, which indicated that the stability of the symbiotic system was affected after CuNP exposure. We speculated that the increased energy demand in the host and symbiotic algae resulted from oxidative stress, precipitating the decrease of the photosynthetic products provided to the host, the digestion of the symbiont, and the destruction of the stable symbiotic relationship. The study provides the first insight into the mechanisms of nanoparticles' toxicity to the symbiotic relationship in the ecosystem, which may help to understand the environmental effects and toxicological mechanisms of nanoparticles.
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The Class Nassophorea is not monophyletic with unsolved relationship of four orders, which calls for discussion to combine morphological features and molecular phylogeny. In the present study, the ultrastructure of Apocolpodidium etoschense in the order Colpodidiida is first studied. Comparisons between orders of Nassophorea were conducted and a discussion of systematics was performed based on a SSU rRNA gene-based phylogeny. The order Colpodidiida and Nassulida shared the following features: Two pairs of alveolocysts in the cortex, the presence of a ''B-cartwheel'' in the distal region of the kinetosome, the presence of cytostomal lamellae and subcytostomal lamellae in the cytopharyngeal basket, and spindle trichocysts with a simple tip. These similarities shape a core group of Nassophorea, which are morphologically and genetically different from the order Microthoracida. Consequently, Microthoracida should be regarded as an independent taxon rather than a member of Nassophorea. Within the core group of Nassophorea, Colpodidiida as an independent order is further validated by its delicate cytopharyngeal basket which lacks nematodesmal lamellae; while the non-monophyly of the order Nassulida might be explained by differentiation of the cartwheels in kinetosomes and the arrangement of kinetosomes with postciliary microtubules in the nassulid organelle 3 within its members.
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Cilióforos , FilogeniaRESUMEN
Direct bioconversion of high concentration of volatile fatty acids (VFAs) into microbial lipid is challenging due to the aggravated cytotoxicity of VFAs at high loadings. Herein, a robust oleaginous yeast Trichosporon cutaneum was screened for lipogenesis from high concentration of VFAs using a regular batch culture. Biomass and lipid content of 8.9 g/L and 49.1%, respectively, were attained from 50 g/L acetic acid with 90.9% of which assimilated within 10 days. The blend of VFAs (50 g/L), with mass ratio of acetic, propionic, and butyric acids of 6:3:1, was found superior to acetic acid for lipogenesis. Biomass and lipid titer increased by 16.9% and 18.2%, respectively, with the three VFAs completely consumed within 8 days. Butyric acid was assimilated simultaneously with acetic acid at the beginning of the culture. Heptadecanoic acid (C17:0) and heptadecenoic acid (C17:1) were produced when propionic acid co-existed with acetic and butyric acids. The estimation of biodiesel properties indicated that lipid prepared from VFA blend showed superiority to acetic acid for high-quality biodiesel production. This study strongly supported that T. cutaneum permitted high concentration of VFA mixture for lipid production.
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Biocombustibles , Trichosporon , Ácido Acético , Basidiomycota , Ácido Butírico , Ácidos Grasos , Ácidos Grasos Volátiles , LípidosRESUMEN
Fatty acids (FA) are widely used as feed stocks for the production of cosmetics, personal hygiene products, lubricants and biofuels. Ogataea polymorpha is considered as an ideal chassis for bio-manufacturing, due to its outstanding characteristics such as methylotroph, thermal-tolerance and wide substrate spectrum. In this study, we harnessed O. polymorpha for overproduction of fatty acids by engineering its fatty acid metabolism and optimizing the fermentation process. The engineered strain produced 1.86 g/L FAs under the optimized shake-flask conditions (37â, pH 6.4, a C/N ratio of 120 and an OD600 of seed culture of 6-8). The fed-batch fermentation process was further optimized by using a dissolved oxygen (DO) control strategy. The C/N ratio of initial medium was 17.5, and the glucose medium with a C/N ratio of 120 was fed when the DO was higher than 30%. This operation resulted in a titer of 18.0 g/L FA, indicating the potential of using O. polymorpha as an efficient cell factory for the production of FA.
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Ácidos Grasos , Saccharomycetales , Medios de Cultivo , Fermentación , Ingeniería Metabólica , Saccharomycetales/genética , Saccharomycetales/metabolismoRESUMEN
Metal sulfides are recognized as potential candidates for the anode materials of lithium ion batteries (LIBs) because of their high theoretical capacity. However, the low reaction kinetics of metal sulfides leads to their poor cycle life and rate performance, which limits their practical application in the field of energy storage. In this work, we synthesized a self-assembled carbon-free vanadium sulfide (V3S4) nanosheet via a facile and efficient method. The unique mesoporous nanostructure of V3S4 can not only accelerate the migration of ions/electrons, but also alleviate the volume expansion during the lithium ion insertion/extraction process. When used as the anode material of LIBs, the carbon-free V3S4 electrode exhibits remarkable electrochemical performance with ultra-high charge capacity (1099.3 mAh g-1 at 0.1 A g-1), superior rate capability (668.8 mAh g-1 at 2 A g-1 and 588.8 mAh g-1 at 5 A g-1) and impressive cycling ability (369.6 mAh g-1 after 200 cycles at 10 A g -1), which is very competitive compared with those of most metal sulfides-based anode materials reported so far. The strategy in this work provides inspiration for the rational design of advanced nanostructured electrode materials for energy storage devices.
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This study is designed to investigate the roles of five key terminal electron acceptors (TEAs): O2, NO3-, Fe3+, SO42-, and CH2O, typically existing in the sludge on the degradation rates and pathways of three representative MPs: polylactic acid (PLA), polyvinyl chloride (PVC), and polyhydroxyalkanoate (PHA). The results revealed that approximately 51.46 â¼ 52.70% of PHA was degraded within 43 days, despite PLA and PVC being degraded insignificantly. Different TEAs significantly affected the end-products of PHA. The production rate of acetate gradually decreased from 90.48, 42.67, 38.30, and 17.56 to 3.30% when the TEAs were tested with CH2O, O2, SO42-, NO3- and Fe3+, respectively. The main functional bacteria involved in the PHA degradation were hydrolysis bacteria Burkholderiaceae and homo-acetogenic bacteria Clostridiacea, which accounted for 0.83% and 18.91% of the microbes. The current investigation could help improve understanding of MPs degradation pathways and mechanisms and minimize their risks in practice.