• Antibiotic azithromycin employed in graphite electrode for EAB biosensor.• Azithromycin at 0.5% dosage increased the sensitivity for toxic formaldehyde.• Azithromycin increased the relative abundance of Geobacter.• Azithromycin regulated thickness of electroactive biofilm. Extensive research has been carried out for improved sensitivity of electroactive biofilm-based sensor (EAB-sensor), which is recognized as a useful tool in water quality early-warning. Antibiotic that is employed widely to treat infection has been proved feasible in this study to regulate the EAB and to increase the EAB-biosensor’s sensitivity. A novel composite electrode was prepared using azithromycin (AZM) and graphite powder (GP), namely AZM@GP electrode, and was employed as the anode in EAB-biosensor. Different dosages of AZM, i.e., 2 mg, 4 mg, and 8 mg, referred to as 0.25%, 0.5% and 1% AZM@GP were under examination. Results showed that EAB-biosensor was greatly benefited from appropriate dosage of AZM (0.5% AZM@GP) with reduced start-up time period, comparatively higher voltage output, more readable electrical signal and increased inhibition rate (30%-65% higher than control sensor with GP electrode) when exposing to toxic formaldehyde. This may be attributed to the fact that AZM inhibited the growth of non-EAM without much influence on the physiologic or metabolism activities of EAM under proper dosage. Further investigation of the biofilm morphology and microbial community analysis suggested that the biofilm formation was optimized with reduced thickness and enriched Geobacter with 0.5% AZM@GP dosage. This novel electrode is easily fabricated and equipped, and therefore would be a promising way to facilitate the practical application of EAB-sensors. 相似文献
● Collaborative treatment of plastics and OS was established to improve oil quality.● PE addition successfully improved OS pyrolysis process by deploying H/Ceff ratio. ● Higher H/Ceff ratio promoted cracking to obtain more gas and light oil fractions. ● The degradation of PE and OS was promoted each other under their temperature range. Pyrolysis is an effective method to treat oily sludge (OS) due to its balance between oil recovery and nonhazardous disposal. However, tank bottom OS contains a high content of heavy fractions, which creates obstacles for pyrolysis due to the high activation energy. The incomplete cracking of macromolecules and secondary polymerization decreases the oil quality and causes coking during the operation process. This study introduced polyethylene (PE) into OS to deploy the H/Ceff ratio of feedstocks for pyrolysis. A strong interaction between OS and PE during copyrolysis could be observed from the TG/DTG curves. PE tightly participated in OS degradation, while OS also promoted PE degradation at high temperature. Apparent pits were generated in solid residues from copyrolysis, which was attributed to the uniform and violent gas release. In addition to HCN, other nitrogenous and sulphurous pollutants were inhibited. Accordingly, more gas products were attained after PE addition with more value-added compositions of alkanes and alkenes. Although the oil yield decreased after PE addition, the oil products from copyrolysis possessed higher heating values and higher contents of light fractions with short chains as well as paraffins. Consequently, copyrolysis of OS and PE significantly improved the pyrolysis process and resulted in high oil quality. 相似文献
• Water-dispersible nano-pollutions exhibit type-specific toxic effects on E. coli.• Global metabolite profiling was used to characterize metabolic disruption patterns.• Key dysregulated metabolites responsive to nano-pollution exposures were found.• Amino acid metabolism and purine metabolism are perturbed at nano-pollutions. Incomplete separation and recycling of nanoparticles are causing undesirable nanopollution and thus raising great concerns with regard to nanosafety. Since microorganisms are important regulator of physiological processes in many organisms, the interaction between nanopollution and microbial metabolomics and the resultant impact on the host’s health are important but unclear. To investigate how typical nanopollution perturbs microbial growth and metabolism, Escherichia coli (E. coli) in vitro was treated with six water-dispersible nanomaterials (nanoplastic, nanosilver, nano-TiO2, nano-ZnO, semiconductor quantum dots (QDs), carbon dots (CDs)) at human-/environment-relevant concentration levels. The nanomaterials exhibited type-specific toxic effects on E. coli growth. Global metabolite profiling was used to characterize metabolic disruption patterns in the model microorganism exposed to different nanopollutants. The percentage of significant metabolites (p<0.05, VIP>1) accounted for 6%–38% of the total 293 identified metabolites in each of the nanomaterial-contaminated bacterial groups. Metabolic results also exhibited significant differences between different nanopollutants and dose levels, revealing type-specific and untypical concentration-dependent metabolic responses. Key metabolites responsive to nanopollution exposures were mainly involved in amino acid and purine metabolisms, where 5, 4, and 7 significant metabolic features were included in arginine and proline metabolism, phenylalanine metabolism, and purine metabolism, respectively. In conclusion, this study horizontally compared and demonstrated how typical nanopollution perturbs microbial growth and metabolomics in a type-specific manner, which broadens our understanding of the ecotoxicity of nanopollutants on microorganisms. 相似文献
Environmental Science and Pollution Research - Many advanced technologies have shown encouraging results in removing antibiotics from domestic wastewater. However, as activated sludge treatment is... 相似文献