Yong Xiao

Chinese Acadeny of Sciences · Institue of Urban Environment

Extracellular electron transfer (EET) is a biological mechanism that plays a crucial role in various bioelectrochemical systems (BESs) and has substantial implications for renewable energy production. By utilizing the metabolic capacities of exoelectrogens, BESs offer a viable and environmentally friendly approach to electricity generation and chem...

Interspecific competition is one of the most important metabolic interactions within microbial communities, and exoelectrogenic bacteria that can conduct extracellular electron transfer act essential roles in nature and engineering systems for pollutants removal. In the present study, we investigated the long-term impact of substrate competition fr...

Electroactive microorganisms have received a lot of interest in the field of environmental engineering and biotechnology because of their extracellular electron transfer (EET) capability of energy recovery and environmental remediation. However, the low efficiency of EET remains a barrier to its practical implementation. This review presents an int...

Active pharmaceutical ingredients (APIs) and their intermediate residues have recently been considered a serious concern. Among technologies, bio-electrochemical technologies (BETs) have stimulated the production of bio-electrical energy. This review aims to examine the benefit and mechanism of BETs on the degradation of high-consumption pharmaceut...

New nanostructures often reflect new and exciting properties. Here, we present an two-dimensional, hitherto unreported PdO square network with lateral dimensions up to hundreds of nanometers growing on reduced graphene oxide (rGO), forming a hybrid nanofilm. An intermediate state of dissolved Pd(0) in the bacterium S. oneidensis MR-1 is pivotal in...

Biological wastewater treatment is a process in which the microbial metabolism of complex communities transforms pollutants into low- or non-toxic products. Due to the absence of an in-depth understanding of the diversity and complexity of microbial communities, it is very likely to ignore the potential mechanisms of microbial community in wastewat...

The performance of bioelectrochemical systems (BESs) is significantly influenced by metabolic interactions within a particular microbial community. Although some studies show that interspecific metabolic cooperation benefits BESs performance, the effect of interspecific substrate competition on BESs performance has not yet been discussed. Herein, t...

The incubation and release of super pathogens from environmental biotechnologies is an overlooked threat to global health. This perspective calls for collaboration between research community, industry and government to mitigate this growing risk.

The biosynthesis of metallic nanomaterials, especially noble metal nanomaterials, has attracted extensive attention due to the multifarious potential applications of these materials. In this study we have explored the effects of Cu(II) on Pd(II) removal, and of Cu(II) as well as phosphate on the morphologies and composition of biogenic nanoparticle...

Escherichia coli is one of the most important model bacteria in microorganism research and is broadly encountered in nature. In the present study, a wild-type E. coli strain K-12 was used for electrochemical investigations. Differential pulse voltammetry showed five pairs of redox peaks both for K-12 cells and the supernatant with potentials (anodi...

Naproxen, a widely used nonsteroidal anti-inflammatory drug, has been detected in many environmental matrixes and is regarded as an emerging pollutant. Sulfate radical (SO4·-) -based advanced oxidation processes have attracted wide attention due to their high efficiency and applicability in the removal of emerging contaminants. In this study, CuFe2...

Combined pollution of antibiotic and non-antibiotic pharmaceutical residues is ubiquitous in realistic polluted environments, which is regarded as a complicated emerging pollution. Herein, high-throughput sequencing and high-throughput quantitative PCR were applied to profile the overall changes in microbial communities and antibiotic resistance ge...

Efficient cathode performance is crucial for the power generation of microbial fuel cells (MFCs). Therefore, the development of a cost effective and efficient cathode is urgently needed for the wider application of MFCs. In this study, a novel biochar air cathode with naturally porous structure and high oxygen reduction reaction (ORR) activity prep...

Bioelectricity generation, by Shewanella oneidensis (S. oneidensis) MR-1, has become particularly alluring, thanks to its extraordinary prospects for energy production, pollution treatment, and biosynthesis. Attempts to improve its technological output by modification of S. oneidensis MR-1 remains complicated, expensive and inefficient. Herein, we...

Acclimation is the main method to enhance the productivity of microorganisms in environmental biotechnology, but it remains uncertain how microorganisms acquire resistance to high concentrations of pollutants during long-term acclimation. Shewanella oneidensis MR-1 was acclimated for 120 days with increasing hexavalent chromium (Cr(VI)) concentrati...

Nanocatalysts synthesized by bacteria, mainly Shewanella oneidensis MR-1, are reviewed. Mechanisms of nanocatalyst biosynthesis by S. oneidensis MR-1, including intracellular and extracellular biosynthesis, are also discussed. We present characterization techniques such as UV-Vis spectroscopy, scanning electron microscopy (SEM), transmission electr...

Metal nanoparticles have been widely applied in many fields,including materials, catalysis, medicine, environment, etc. Furthermore, nanoparticles from noble metal, such as gold, silver, platinum, palladium, possess the ability of increasing the efficiency of catalytic reaction. Therefore, the synthesis of noble metal nanoparticles by microorganism...

The extracellular electron transfer of Shewanella oneidensis MR-1 (MR-1) has been extensively studied due to the importance of the biosensors and energy applications of bioelectrochemical systems. However, the oxidation of metal compounds by MR-1, which represents the inward extracellular electron transfer from extracellular electron donors into th...

Hexavalent chromium [Cr(VI)] is a priority heavy metal pollutant causing a series of environmental issues, and bio-reduction of Cr(VI) to trivalent chromium can remarkably decrease the environmental risk of Cr(VI). The reduction and resistance abilities of microorganisms to Cr(VI) can be dramatically improved by acclimatization. In the present stud...

The network of microbial electron transfer can establish a syntrophic association of microbes by connecting interspecies metabolisms, and a variety of redox-active shuttles in environment have been proved to accelerate the electron flow in a microbial community. Using humic substances as models, we investigated how different redox-active shuttles w...

Increasing human activities, a great demand for animal protein and intensive use of antibiotics, are responsible for the persistent emergence of antibiotic contaminants in the environment. Increased attention has been paid to this pollution because it possibly exacerbates the appearance of antibiotic resistance bacteria and antibiotic resistance ge...

Intimately coupled photocatalysis and biodegradation (ICPB) is a novel wastewater treatment technique that has potential applications in refractory degradation. This paper reports a synergistic degradation protocol that allowing the transfer of photoelectrons between photocatalysts and microbes without supplementary electron donors or improving the...

Microbial fuel cell (MFC) is regarded as a promising alternative for enhancing the removal of antibiotic pollutants. In this study, oxytetracycline served as an electron donor in the anode chamber of MFCs, and after continuous operation for 330 days, the efficiency of removal of 10 mg/L oxytetracycline in MFCs increased to 99.00% in 78 h, whereas r...

Production of molecular scale palladium (Pd) nanoparticles (NPs) is important due to their catalytic function in electrochemical oxidation of a number of core fuel molecules in fuel cells. Biogenetic methods offer an economic and environmentally friendly synthesis route. In this work, the electrochemically active bacterium Shewanella oneidensis MR-...

The extracellular electron transfer (EET) mechanism of an isolated Gram-positive Bacillus megaterium strain (LLD-1), identified by 16S rRNA gene sequencing and physiological analysis, was investigated in the present study. The electrochemical activity of strain LLD-1 was confirmed by electrochemical E-t and amperometric I-t tests. Flavins in cultur...

Most microbial cells in nature are surrounded by extracellular polymeric substances (EPS), which are fundamental components and determine the physiochemical properties of a biofilm. This review highlights the EPS properties of conductivity and redox ability from an electrochemical perspective, emphasizing recent findings that EPS play important rol...

Microorganisms exploit extracellular electron transfer (EET) in growth and information exchange with external environments or with other cells. Every microbial cell is surrounded by extracellular polymeric substances (EPS). Understanding the roles of three-dimensional (3D) EPS in EET is essential in microbiology and microbial exploitation for miner...

Increasing attention is being paid to the adoption of photoautotrophic microbes in bioelectrochemical systems (BESs) because of the advantages of self-sustainability. Biased potential on the anode was capable of adjusting the performance of non-photo BESs, and the microbial community structure was also changed; however, few studies have been conduc...

Extracellular polymeric substances (EPS) play crucial roles in bio-aggregate formation and survival of bacterial cells. To develop an effective but harmless method for EPS extraction from Shewanella oneidensis MR-1, five extraction methods, i.e. centrifugation (control), heating (40, 45, 50, and 60 °C), and treatments with H2SO4, ethylenediaminetet...

Light source can affect the stomata opening, photosynthesis process, and pigment content in microalgae cells. In this study, growth rate, chlorophyll a (chl a) content, and electrogenic capability of Desmodesmus sp. A8 were investigated under incandescent and fluorescent lamps. Growth rate, productivity, and chl a content of strain A8 exposed to in...

Bioelectrochemical systems (BESs) are promising technologies for energy and product recovery coupled with wastewater treatment, and the core microbial community in electrochemically active biofilm in BESs remains controversy. In the present study, 7 anodic communities from 6 bioelectrochemical systems in 4 labs in southeast, north and south-central...

In the present study, isopropyl alcohol containing wastewater generated from silicon solar cell manufacture was sequentially treated with sequencing batch biofilm reactor and sequencing batch reactor. Sequencing batch biofilm reactor could remove 90 % of isopropyl alcohol from wastewater efficiently as the chemical oxygen demand lower than 1,200 mg...

Soil acidification has been a threat to sustainable agricultural development as a global environmental problem. The bioelectrochemistry system (BES) is an eco-friendly and low-cost technique for ameliorating acidic soil when compared with traditional technologies. Here, operational parameters from soil load and external resistance were investigated...

Extracellular electron transfer (EET) between electrochemically active microorganisms and electrodes plays a key role in microbial electrochemical systems (MESs) functioning of energy generation, bioremediation, etc. At present, researchers have a very limited understanding of the mechanism of EET, which is one of the major bottlenecks in applicati...

Few studies have been conducted to explore the community composition in denitrifying biocathode. Herein, the microbial communities of denitrifying biocathodes yielding current of 1 mA (reactor C1) and 1.5 mA (reactor C2) were characterized by 454 pyrosequencing. The nitrate removal efficiencies in C1 and C2 were about 93 and 85 %, respectively. The...

Nitrogen is one of major contaminants in wastewater; however, nitrogen, as bio-elements for crop growth, is the indispensable fertilizer in agriculture. In this study, two-chamber microbial fuel cells (MFCs) were first operated with microorganisms in anode chamber and potassium ferricyanide as catholyte. After being successfully startup, the two-ch...

Bioelectrochemical system (BES), in which electrode reaction is driven by electrochemically active microorganisms (EAM) to recovery energy, degrade contaminants and synthesize high additional value compounds, is a promising biotechnology. EAM is the basis of BES, microorganisms-electrode interaction plays a key role in BES functioning. In contrast...

Microbes play irreplaceable role in oxygen reduction reaction of biocathode in microbial fuel cells (MFCs). In this study, air-diffusion biocathode MFCs were set up for accelerating oxygen reduction and microbial community analysis. Linear sweep voltammetry and Tafel curve confirmed the function of cathode biofilm to catalyze oxygen reduction. Micr...

Microbial fuel cells (MFCs) in negative pressure environment can provide an increase of 20% in voltage output and a maximum power generation of 7 times compared with that in normal environment. As showed by denaturing gradient gel electrophoresis, the culture in negative pressure environment for 30 days had little effect on diversity of bacterial c...

Biofilms are the core component of bioelectrochemical systems (BESs). To understand the polarization effects on biocathode performance of BES, dissolved oxygen concentrations, pHs and oxidation-reduction potentials of biofilm microenvironments were determined in situ. The results showed that lower polarization potentials resulted in the generation...

The suitability of the application of ultrafiltration (UF) to harvest Chlorella sp. from the culture medium was examined. We investigated the effects of two improved UF system, forward air-water flushing and backwash with permeate, on the concentration process. Backwash with permeate was selected as an optimization of the improved UF system, which...

Microbial fuel cells (MFCs) produce electricity, which is clean and renewable energy, through degradation of pollutants in wastewater by microorganism. MFC biocathode refers to microorganisms attaching on electrode surface to form biofilm while electron transferred from cathode to microorganisms via bioelectrochemistry reactions. This review introd...

The effects of pH on sulfate pollutant removal, power generation and microbial community were investigated using a bioelectrochemical system, which was built on acclimatized sludge with sulfate at different pHs. For the experiment, ethanol was used as the electron donor for the reduction of sulfate pollutant. In the range of pHs between 2.5 and 10....

The method of continuous thermophilic composting (CTC) remarkably shortened the active composting cycle and enhanced the compost stability. Effects of CTC on the quantities of bacteria, with a comparison to the traditional composting (TC) method, were explored by plate count with incubation at 30, 40 and 50°C, respectively, and by quantitative PCR...

This study aims at evaluating the impacts of PAM addition on activated sludge performance. Four lab-scale sequencing batch reactors (SBRs), each with a working volume of 3L, were investigated with different PAM concentrations. Experiments were conducted with varying organic loading rate and the sludge volume index (SVI), particle size, zeta potenti...

Actinomycetes degrade cellulose and solubilize lignin during composting. Changes in the diversity of the actinomycetal communities and the 16S rDNA copy numbers of actinomycetes were monitored by denaturing gradient gel electrophoresis (DGGE) and quantitative PCR (qPCR), respectively, during continuous thermophilic composting (CTC) and traditional...

A biological treatment with the integration of partial nitrification, anaerobic ammonium oxidation (Anammox) and heterotrophic denitrification was successfully developed in a SBR with periodical air supply to treat landfill leachate. An operating temperature of 30+/-1 degrees C and a dissolved oxygen concentration within 1.0-1.5 mg/L were maintaine...

Fewer and fewer municipal solid wastes are treated by composting in China because of the disadvantages of enormous investment, long processing cycle and unstable products in a conventional composting treatment. In this study, a continuous thermophilic composting (CTC) method, only a thermophilic phase within the process, has been applied to four be...

The bacterial diversity in a sequencing batch biofilm reactor (SBBR) treating landfill leachate was studied to explain the mechanism of nitrogen removal. The total microbial DNA was extracted from samples collected from landfill leachate and biofilm of the reactor with the removal efficiencies of NH(4) (+)-N higher than 97% and that of chemical oxy...

The differences on DNA yield and purity of three different DNA extraction protocols were compared with regard to the use for PCR and other molecular analyses. Total DNA was extracted from compost by the three protocols, and then was purified by spin-bind cartridges after being precipitated by PEG8000. The detection performed on a nucleic acid and p...