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•Air-cathode SCMFC was successfully started by the Thauera-dominated aerobic denitrifying inoculum.•The aerobic consortium grew well and had high performances in the anaerobic ...SCMFC.•The biofilm at the water-facing side of the air cathode could complete nitrification and denitrification simultaneously.•The denitrifying bacteria were affiliated with the genera Thauera, Nitrosomonas, Desulfomicrobium and Thiobacillus.
Electrochemically active bacteria (EAB) usually catalyze the electrochemical reactions on the electrodes of microbial fuel cells (MFCs) to fulfill organic oxidation and electricity generation. In this work, an aerobic consortium of Thauera-dominated denitrifiers was investigated in anaerobic single chambered MFC (SCMFC) for simultaneous electricity generation and pollutants removal. Using a batch regime feeding COD (240 mg L−1) and ammonia (130 mg L−1), the removal efficiencies of COD, ammonia and total nitrogen (TN) obtained highly at 90%, 98%, and 95%, respectively, and a maximum power output of 1250 ± 20 mW m−2 was found. High-throughput sequencing illustrated that the dominant species at the anode was Thauera (75% abundance), indicating its important role in oxidation reactions and electron transfer. At the water-facing side of the air cathode, the predominated bacteria were Thauera (43–74%), Nitrosomonas (3–8%), Desulfomicrobium (1–8%) and Thiobacillus (3–5%), which are involved in nitrification/denitrification process. It can be inferred that complete nitrogen removal may facilitate simultaneous nitrification/denitrification with such inoculum. Furthermore, cyclic voltammetry measurements showed obvious oxidation peaks at −0.40 V and +0.60 V, which indicated that the anode with Thauera-dominated consortium could efficiently catalyze oxidation reactions of organic matter for current generation and nitrogen removal. Therefore, it was demonstrated that to introduce the Thauera-dominated aerobic denitrifying consortium into MFCs is a new and promising approach to enrich EAB for wastewater treatment.
Small ruminants are the critical source of livelihood for rural people to the development of sustainable and environmentally sound production systems. They provided a source of meat, milk, skin, and ...fiber. The several contributions of small ruminants to the economy of millions of rural people are however being challenged by extreme heat stress difficulties. Heat stress is one of the most detrimental factors contributing to reduced growth, production, reproduction performance, milk quantity and quality, as well as natural immunity, making animals more vulnerable to diseases and even death. However, small ruminants have successfully adapted to this extreme environment and possess some unique adaptive traits due to behavioral, morphological, physiological, and largely genetic bases. This review paper, therefore, aims to provide an integrative explanation of small ruminant adaptation to heat stress and address some responsible candidate genes in adapting to thermal-stressed environments.
Production of upgraded biogas is required to remove as much carbon dioxide as possible. It was found that by coupling microbial electrolysis cell (MEC) and anaerobic digestion (AD) in a ...single-chamber, barrel-shape stainless steel reactor, compared with common anaerobic digestion (control), CH4 content in excess of 98% was achieved and CH4 yield was increased 2.3 times. Meanwhile, the COD removal rate was tripled and carbon recovery was increased by 56.2%. In this new process, unwanted CO2 was in situ converted into CH4 on anode by the dominant microbes, hydrogenotrophic electromethanogens (e.g. Methanospirillum). These microbes could utilize hydrogen gas generated at the inner surface of stainless steel reactor, which itself served as cathode of MEC through small voltage addition (1.0V). The overall energy efficiency was 66.7%.
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•CH4 content in excess of 98% was achieved from microbial electrolysis cell and anaerobic digestion coupled process.•COD removal rate was increased 3.0 times and carbon recovery was increased by 56.2%.•Reactor made of stainless steel was used for anaerobic digestion as well as the MEC cathode for H2 gas evolution.
Alpha-glucosidase is one of the main enzymes responsible for digesting starch. Inhibiting its activity is therefore being targeted as a strategy for tackling diabetes. Certain food components have ...the potential to act as natural α-glucosidase (SCG) inhibitors, such as the polyphenols found in tea. In this study, epigallocatechin gallate (EGCG) was shown to strongly inhibit SCG activity (IC50 value = 3.7 × 10−5 M). Multi-spectroscopic binding molecular simulations indicated that EGCG spontaneously bound to SCG through a combination of hydrogen bonding and hydrophobic interactions. The hypothesis was supported by the results from intrinsic fluorescence quenching, conformational change, surface hydrophobicity decrease, and molecular docking analysis of the SCG after binding. Molecular docking provided powerful visual insights into the nature of the molecular interactions involved. This research provides important new information about the interaction mechanism of EGCG and SCG, which may be beneficial to the development of functional foods to prevent diabetes.
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•A tea polyphenol (EGCG) significantly inhibited α-glucosidase (SCG) activity.•The major EGCG-SCG interaction was hydrophobic in origin.•The conformation of SCG was changed after interacting with EGCG.•Molecular binding simulations provided insights into the interaction mechanism.
Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) are the main pathogenic microorganisms causing sexually transmitted infections. In this study, a multiplex thermostable recombinase ...polymerase amplification-lateral flow detection (RPA-LFD) assay was established, and the reaction conditions such as the ratio of primer concentration, magnesium ion concentration, amplification time and template DNA concentration in the multiplex RPA reaction were optimized. The optimized multiplex RPA-LFD method was used to detect both CT and NG positive control plasmids, and it was found that the LFD could be used to obtain visible results when the plasmid copy number was only 200. The sensitivity of the multiplex RPA-LFD method used for clinical samples was 85.62 (95% CI at 53.66-97.29) for NG detection and 90.90 (95% CI at 57.12-99.52) for CT detection.
In response to various stimuli, naïve macrophages usually polarize to M1 (classically activated) or M2 (alternatively activated) cells with distinct biological functions. Neuronal nitric oxide ...synthase (NOS1) is involved in M1 macrophage polarization at an early stage. Here, we show for the first time that NOS1 is dispensable for M2 macrophage polarization for the first time. Further, differentially expressed genes (DEGs) regulated by NOS1 signaling in M1-polarized macrophages stimulated with lipopolysaccharide (LPS) were characterized by transcriptome analysis of wild-type (WT) and NOS1 knockout mouse macrophages. Thousands of affected genes were detected 2 h post LPS challenge, and this wide-ranging effect became greater with a longer stimulation time (8 h post LPS). NOS1 deficiency caused dysregulated expression of hundreds of LPS-responsive genes. Most DEGs were enriched in biological processes related to transcription and regulation of the immune and inflammatory response. At 2 h post-LPS, the toll-like receptor (TLR) signaling pathway, cytokine-cytokine receptor interaction, and NOD-like receptor signaling pathway were the major pathways affected, whereas the main pathways affected at 8 h post-LPS were Th1 and Th2 cell differentiation, FoxO, and AMPK signaling pathway. Identified DEGs were validated by real-time quantitative PCR and interacted in a complicated signaling pathway network. Collectively, our data show that NOS1 is dispensable for M2 macrophage polarization and reveal novel insights in the role of NOS1 signaling at different stages of M1 macrophage polarization through distinct TLR4 plasma membrane-localized and endosome-internalized signaling pathways.
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•Non-aeration-based UBEF for domestic wastewater treatment was operated during almost 5 months.•Air-exposed biocathode assured the stable performance of UBEF.•High removal efficiency ...of real domestic wastewater was attained.•Microbial community were analyzed and compared for operation at different HRTs.•UBEF has a promise for sustainable wastewater treatment by scale-up MFC.
Domestic wastewater treatment process via the activated sludge is complicated, energy-negative and potentially harmful. In this study, an up-flow bioelectrochemical filter reactor (UBEF) was designed without positive aeration in-priority for treating real domestic wastewater under different hydraulic retention times (HRTs). The removal of chemical oxygen demand (COD), ammonia and total nitrogen was attained at a high efficiency of 89%, 99% and 99% respectively, when HRT was set at h1 of ∼2.53 d. However, with the decreased of HRT from 2.53 to 0.28 d, the removal efficiency of nitrogen and COD decreased to 50% and 40% respectively, but the maximum power density increased from 3.01 to 98.90 mW/m3 with a low Coulombic efficiency of 0.25–1.51%. The results demonstrated that the UBEF can remove COD and ammonia from real domestic wastewater in an aeration-free energy sustainable process, although its power output was low. Moreover, the functional bacteria were detected using 16S rRNA gene-based pyrosequencing analysis, which showed that the microbial communities were different under varied HRT conditions. The Thauera-dominated consortium was inoculated in order to enhance the removal of pollutants and the generation of electricity from domestic wastewater, it was kept at a relative abundance when continuously feeding the real wastewater. In particular, nitrogen removing bacteria (NRB) including Nitrosomonas, Ignavibacterium, Thiobacillus, Dokdonella, Comamonas, Sterolibacterium and Flavobacterium were enriched on the anode and the cathode of the UBEF, which contributed to nitrogen removal by nitrification and denitrification. Therefore, this study demonstrated that the UBEF configuration had great potential applicability for energy sustainable wastewater treatment.
The anaerobic digestion（AD）and microbial electrolysis cell（MEC）coupled system has been proved to be a promising process for biomethane production.In this paper,it was found that by co-cultivating ...Geobacter with Methanosarcina in an AD–MEC coupled system,methane yield was further increased by 24.1%,achieving to 360.2 m L/g-COD,which was comparable to the theoretical methane yield of an anaerobic digester.With the presence of Geobacter,the maximum chemical oxygen demand（COD）removal rate（216.8 mg COD/（L·hr））and current density（304.3 A/m3）were both increased by 1.3 and 1.8 fold compared to the previous study without Geobacter,resulting in overall energy efficiency reaching up to 74.6%.Community analysis demonstrated that Geobacter and Methanosarcina could coexist together in the biofilm,and the electrochemical activities of both were confirmed by cyclic voltammetry.Our study observed that the carbon dioxide content in total gas generated from the AD reactor with Geobacter was only half of that generated from the same reactor without Geobacter,suggesting that Methanosarcina may obtain the electron transferred from Geobacter for the reduction of carbon dioxide to methane.Taken together,Geobacter not only can improve the performance of the MEC system,but also can enhance methane production.
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Self-assembled monolayers (SAMs) of N-heterocyclic carbene (NHC) are built up on gold substrate. Electrochemical impedance spectroscopy (EIS) tests show that the NHC-based SAMs ...exhibit high stability under ultrasonic circumstance, over 90% of NHC molecules being retained at gold surfaces after ultrasonic treatment of 10min in water. Computations of density functional theory (DFT) demonstrate the preferential adsorption of NHC molecules at atop sites of Au (1 1 1) plane, and the strong interaction between NHC molecules and Au surfaces is attributed to the bonding between 2-position C atoms and Au atoms by the hybridization of the C 2p orbitals with the Au 5d and 6s orbitals.
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