A full-scale treatment wetland (TW) (100 inhabitants, 14 m·d), composed of two horizontal subsurface flow wetlands (TW1-400 m and TW2-200 m) and a small pond (13 m), has been evaluated for Escherichia coli (E. coli) removal. The results indicate a global removal from 1.74·10 to 685 MPN·100 mL (3.41 log units), reducing E. coli sufficiently to reach values suitable for reuse purposes such as agricultural reuse, without energy and reagent consumption. The small pond at the end of the treatment train plays an important role in E. coli removal and biodiversity enhancement. Data from TW1 and TW2 have been fitted to the P-k-C* model, giving values of 134 and 100 m·yr for the first-order kinetic reaction coefficient. For the pond, a process-based model using continuous stirred-tank reactor (CSTR) and a 3d-CFD model have been implemented and compared. The models indicate that solar disinfection and predation by daphnids are the most important mechanisms in the studied pond, representing 65% and 25% of the removal respectively. It can be concluded that CSTR can provide good results for small ponds and 3d-CFD model provides extra information, useful to enhance their design.
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http://dx.doi.org/10.1016/j.scitotenv.2022.156237 | DOI Listing |
Int J Biol Macromol
January 2025
College of Animal Science and Technology, Henan Agricultural University, Zhengzhou 450046, China. Electronic address:
Zearalenone (ZEN) is a harmful macrolide mycotoxin, posing a serious hazard to human health. In this study, a highly efficient ZEN-degrading bacterium Gordonia hydrophobica HAU421 was isolated from soil by using spiramycin (SPM)-containing selective medium. Mass spectrometry analysis revealed that strain HAU421 could transform ZEN into hydrolyzed zearalenone (HZEN), zearalenol (ZEL), and hydrolyzed zearalenol (HZEL).
View Article and Find Full Text PDFHeliyon
January 2025
African Centre of Excellence in Future Energies and Electrochemical Systems (ACE-FUELS), Federal University of Technology, Owerri, PMB 1526, Imo State, Nigeria.
The management of wastewater and agricultural wastes has been limited by the separate treatment processes, which exacerbate pollution and contribute to climate change through greenhouse gas emissions. Given the energy demands and financial burdens of traditional treatment facilities, there is a pressing need for technologies that can concurrently treat solid waste and generate energy. This study aimed to evaluate the feasibility of producing bioelectricity and biohydrogen through the microbial treatment of blackwater and agricultural waste using a dual-chamber Microbial Fuel Cell (MFC).
View Article and Find Full Text PDFActa Crystallogr F Struct Biol Commun
February 2025
Graduate School of Life Science, Hokkaido University, Kita 10, Nishi 8, Kita-ku, Sapporo, Hokkaido 060-0810, Japan.
The bacterial enzyme tRNA 2-selenouridine synthase (SelU) catalyzes the conversion of 5-substituted 2-thiouridine (R5S2U) to 5-substituted 2-selenouridine (R5Se2U) at the wobble positions of several tRNAs. Seleno-modification potentially regulates translation efficiency in response to selenium availability. Notably, SelU uses the 2-geranylthiouridine (R5geS2U) intermediate for sulfur removal, and this geranylthiol (geS) is a unique leaving group among tRNA-maturation enzymes.
View Article and Find Full Text PDFNat Struct Mol Biol
January 2025
Laboratory of Molecular Biophysics, The Rockefeller University, New York, NY, USA.
Following transcript release during intrinsic termination, Escherichia coli RNA polymerase (RNAP) often remains associated with DNA in a post-termination complex (PTC). RNAPs in PTCs are removed from the DNA by the SWI2/SNF2 adenosine triphosphatase (ATPase) RapA. Here we determined PTC structures on negatively supercoiled DNA and with RapA engaged to dislodge the PTC.
View Article and Find Full Text PDFMetab Eng
January 2025
The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kongens Lyngby, Denmark. Electronic address:
Advanced genome engineering enables precise and customizable modifications of bacterial species, and toolsets that exhibit broad-host compatibility are particularly valued owing to their portability. Tn5 transposon vectors have been widely used to establish random integrations of desired DNA sequences into bacterial genomes. However, the iteration of the procedure remains challenging because of the limited availability and reusability of selection markers.
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