Clarkeanker8093
Anode-respiring bacteria (ARB) generate electrical current from the oxidation of short chain fatty acids (SCFA), primarily acetate, in microbial electrolysis cells (MECs). Animal rendering wastewater (RW) has high fat content, which under anaerobic conditions can yield acetate, making RW a potential feed for MECs. Yet, excess intermediate long chain fatty acids (LCFA) may limit conversion of LCFA and SCFA, and impact ARB activity. Here, we evaluated electrical current production in single-chamber MECs fed with RW. In RW-fed MECs, 34.26 ± 2.69% of the COD provided was converted to electrical current in an 80-day batch cycle. LCFA accumulated in RW-fed MECs, during which conversion of acetate to electrical current was limited. Diverse sulfate-reducing microorganisms were present in the anode biofilm in RW-fed MECs, whereas the genus Geobacter dominated in inoculum-only control MECs. Detection of H2-utilizing homoacetogens suggested some internal cycling of H2 produced at the cathode. Overall, this study shows that current production is possible from RW, but to be a viable process for RW treatment, further improvement in rates of COD conversion and current production is necessary along with identifying configurations and/or conditions in which the inhibitory effect of LCFA is reduced.Chemicals can activate a variety of signaling pathways, initiating changes in gene expression and cellular functions. Here, we combined experimental data on the chemical-induced extracellular signal-regulated kinase 1/2 (ERK1/2) activation with the Comparative Toxicogenomics Database (CTD) to connect signaling, genes, and phenotypes to reveal the potential chemical's mode of action (MOA) responsible for the disease state. Experimental data on ERK1/2 activation were derived from the cell-based phospho-ERK1/2 ELISA on human alveolar epithelial cells A549. A549 cells were exposed to bisphenol A (BPA), benzo[a]pyrene (BaP), tributyltin (TBT), and ibuprofen from 10-12 M to 10-5 M. Results show that BPA, BaP, and TBT can activate ERK1/2 in A549 cells. We selected BPA and BaP to elucidate the molecular events connecting chemical exposure, ERK1/2 signaling, phenotypes, and lung neoplasm (LN) using CTD. CTD analysis showed that BPA and BaP share 26 mitogen-activated protein kinase 1/3 (MAPK1/3) signaling genes associated with LN. Phenotype prioritization revealed 37 BPA, 10 BaP, and 11 shared key phenotypes associated with LN. Alignment of MAPK1/3 signaling genes and phenotypes showed that ERK1/2 and oxidative stress, EGFR gene, and positive regulation of cell proliferation and migration could be the shared key events (KE) for BPA and BaP. This analysis also identified protein kinase B and ERK1/2 signaling, FGF9, FGFR1 and FGFR2 genes, positive regulation of cell proliferation and angiogenesis as KE in MOA for BPA, whereas ERK1/2 signaling, IL6 and DAB2IP genes, negative regulation of cell proliferation and inflammatory response were identified as KE in MOA for BaP.Dissolved organic matter (DOM) can play a major role in determining availability of pollutants to aquatic biota. Equilibrium dialysis is the most commonly used method to assess the interaction between DOM and organic contaminants. However, results obtained through this method can be affected by confounding factors linked to the diffusion of DOM through the membrane or the interaction of DOM and/or the compounds with the membrane itself. In this study, we propose an improved experimental approach, where highly hydrophilic cellulose-ester membranes with small molecular cut-off (100-500 Da) were used to overcome some of these hindrances. The performance of the method to determine the binding of a commonly used moderately hydrophobic herbicide (Isoproturon - ISU) with natural DOM was critically evaluated through a set of quality assurance criteria, across a range of DOM concentrations and pH conditions. DOM trans-membrane diffusion was prevented by the smaller pore size of the dialysis membrane. Good measurement reproducibility, mass balance closure, and successful trans-membrane equilibrium of ISU were obtained. ISU showed relatively low affinity with DOM (log KDOC 1-2 L g-1), which was significantly influenced by varying pH and DOM concentration. An alternative membrane may be needed for higher pH conditions as the greater adsorption effect blurred the observation of trans-membrane equilibrium and confounding mass balance closure. The paper makes recommendations on how to avoid measurement artefacts, while considering criteria for the expected mass distribution of compounds at equilibrium and for sorption onto the membrane and surfaces of the experimental units.Azoxystrobin (AZ) has entered aquatic ecosystems and produced serious damages to fish associated with potentially increasing the susceptibility to pathogens. This study characterized the defense abilities of fish by exposed to AZ on challenging with the infection of spring viraemia of carp virus (SVCV). The results showed that SVCV replication increased significantly in EPC cells and zebrafish that were exposed to up to 50 μg/L of AZ at 3, 5, 7, and 14 d. Intracellular biochemical assays indicated that AZ at 5 and 50 μg/L inhibited the activation of Nrf2-ARE pathway including a decrease in Nrf2 expression, Nrf2 phosphorylation, HO-1 content, and three antioxidant activities. While no significant difference in ERK1/2 and JNK MAPKs in zebrafish was observed, P38 phosphorylation was significantly decreased at 7 and 14 d, and the changes in MAPKs were more evident in EPC cells previously exposed to AZ at 7 d. These results revealed that AZ initially induced low phosphorylation of MAPKs, triggering the attenuation of Nrf2 phosphorylation to weaken Nrf2 translocation into the nucleus in a longer exposure period (more than 5 d). The data in the cells and fish also showed that antioxidant activities were decreased to some extent at 5-7 d for the cells and 7-14 d for the fish. Furthermore, interferon-related factors were decreased in AZ-exposed zebrafish, explaining the reason that fish can't resist the virus infection. Overall, the present study provided a new adverse threat of AZ by amplifying the viral outbreak to endanger ecological safety in aquatic environment.Microplastics are frequently found in many environmental media. Polypropylene (PP) is one of the plastics commonly used, resulting in more and more PP fragments in natural waters. Contaminants, such as lead (Pb), could get adsorbed onto microplastics after the exposure to sunlight, and pose a larger threat to aquatic species. In this study, the oxidative indices of PP pellets after different exposure times to a Xenon lamp were evaluated by Fourier transform infrared (FTIR) and energy-dispersive X-ray spectrometry. The results show that the percentage of oxygen content increased from 2.80 to 20.95 wt% and changes of characteristic peaks of the FTIR pattern, implying that the exposure to the Xenon lamp could initiate oxidation. Due to the changes of functional groups after the exposure to the Xenon lamp for 28 days, the adsorption capacities of the PP pellets were up to 274.4 mg⋅kg-1, 1.7 to 2.5 times higher than that of the raw PP pellets depending on the solution pHs. The adsorption behavior can be described by a pseudo-second-order model with rate constants of adsorption of 0.00212-0.01404 kg⋅mg-1⋅h-1. The increase of adsorption capacity due to changes of the PP pellets after the Xenon lamp exposure increased the potential risk to the aquatic species.Currently, Tetrabromobisphenol A (TBBPA) has been regarded as an emerging organic pollutant and efficient TBBPA elimination technology has been attracting increasing attention. In this work, a novel photocatalyst, MoS2/SnIn4S8, was synthesized through hydrothermal method by introducing few-layer MoS2 nanosheets and then employed to establish an integrated photocatalytic reduction/oxidation system for the remediation of TBBPA under visible light. The characterization results demonstrated that the few-layer MoS2 nanosheets were well combined with SnIn4S8 and significantly lowered the recombination rate of the photo-induced electron and holes, leading to outstanding photocatalytic performance of MoS2/SnIn4S8 composite. Besides, the MoS2/SnIn4S8 composite also exhibited excellent reusability (over 10 runs) and stability. The TBBPA degradation experiments showed that the integrated photocatalytic reduction/oxidation system was able to completely degrade TBBPA and mineralize its byproducts (60.2 ± 2.9%). In the photocatalytic reduction, due to the cleavage of C-Br bonds by photo-induced electrons, TBBPA underwent stepwise debromination and finally transferred into BPA in 6 h. In the following photocatalytic oxidation, under the attack of reactive oxygen species (1O2, h+,OH and O2-), BPA was first decomposed into aromatic products (such as phenol, benzoic acid, p-hydroxybenzyl alcohol and so on) via C-C bond cracking and hydroxylation, and then further oxidized into organic acids like maleic acid and muconic acid through ring-opening, and finally mineralized into CO2 and H2O. What was noteworthy was that the final effluent from the photocatalytic reduction/oxidation system showed no toxicity to the luminescent bacteria.Uranium in groundwater during uranium mining activities urgently needs to be remediated through effective and environmental-friendly approaches. The reduction and immobilization of soluble U(VI) using biogenic carboxymethyl cellulose modified iron sulfide complex (biogenic CMC-FeS complex) is one of the emerging and innovative methods. However, its removal mechanism is largely unknown. find protocol Here, biogenic CMC-FeS complex with extracellular polymeric substances (EPS) and CMC was successfully synthesized by sulfate-reducing bacteria (SRB) and showed highly dispersible capacity. The tryptophan and tyrosine, which were the main components in EPS produced by SRB on CMC-FeS surface, significantly increased the U(VI) removal capacity of the biogenic CMC-FeS complex compared with chemically synthesized CMC-FeS. U(VI) removal was attributed to the adsorption of soluble U(VI) by ≡FeO+, CMC, tryptophan, and tyrosine on the biogenic CMC-FeS complex, following its reduction by S2-, S22- and Fe2+. Moreover, biogenic CMC-FeS complex with CMC-to-FeS molar ratio of 0.0005 performed well in the presence of bicarbonate (5 mM), humic acid (10 mg/L), or co-existing cations such as Pb2+, Ni2+, Cd2+, Mn2+, and Cu2+ (200 ug/L) at pH 7.0, and displayed relatively high oxidation resistance and stability ability. This work provides an in-depth understanding of the biogenic CMC-FeS complex for the U(VI) removal and contributes to the development of cost-effective U(VI) remediation technologies.This study investigated the effects of earthworms on the enantioselective degradation of chloroacetamide herbicide acetochlor with soil microorganisms in repeatedly treated soils. The S-enantiomer degraded more slowly and exerted stronger inhibition on soil microbial functions than the R-enantiomer in single soil system. A synergistic effect was observed between soil microorganisms and earthworms that accelerated the degradation of both the enantiomers, particularly the highly toxic S-enantiomer, which resulted in the preferential degradation of S-enantiomer in soil-earthworm system. Earthworms stimulated five potential indigenous degraders (i.e. Lysobacter, Kaistobacter, Flavobacterium, Arenimonas, and Aquicell), induced two new potential degraders (i.e. Aeromonas and Algoriphagus), and also significantly strengthened the correlations among these seven dominant potential degraders and other microorganisms. Notably, the relative abundances of Flavobacterium and Aeromonas in soil treated with earthworms for S-enantiomer were higher than those for R-enantiomer.