A single-atom manganese nanozyme mediated membrane reactor for water decontamination.

Single-atom nanozymes possess high catalytic activity and selectivity, and are emerging as advanced heterogeneous catalysts for environmental applications. Herein, we present the innovative synthesis and characterization of a single-atom manganese-doped carbon nitride (SA-Mn-CN) nanozyme, integrated into a polyvinylidene fluoride (PVDF) membrane for advanced water treatment applications. The SA-Mn-CN nanozyme demonstrates high peroxidase-like activity, efficiently catalyzing the oxidation of 3,3',5,5'-tetramethylbenzidine (TMB) and generating reactive oxygen species (ROS) for effective antibacterial action. Notably, the SA-Mn-CN/PVDF membrane showcases enhanced water permeability, superior antifouling properties, and ultra-fast degradation kinetics of organic pollutants. Mechanistic studies reveal that the nanozyme selectively generates Mn(IV)-oxo species via peroxymonosulfate (PMS) activation, crucial for the efficient oxidation processes. Our integrated membrane system effectively removes (within 1 min, > 92 % removal) a variety of organic micropollutants in continuous-flow operations, demonstrating excellent stability and minimal manganese leaching. Compared to conventional advanced oxidation process (AOPs)/membrane system, the SA-Mn-CN/PVDF/PMS system holds the advantages of high catalytic activity and selectivity for generation of reactive species, wide working pH range (pH3-11) and excellent stability and reusability under the backwashing conditions. The developed device-scale AOPs/membrane system was proven to be effective in bacterial inactivation and pollutants degradation, verifying the vast application potential of the SA-Mn-CN/PVDF membrane for practical water decontamination. This work pioneers the development of enzyme-mimicking nanozyme membranes, offering a sustainable and high-performance solution for wastewater treatment, and sets a new benchmark for the design of nanozyme-based catalytic membranes in environmental applications.

Genome characterization of the novel lytic Vibrio parahaemolyticus phage vB_VpP_BA6.

A lytic bacteriophage, designated Vibrio phage vB_VpP_BA6, was isolated from sewage collected in Guangzhou, China. The double-stranded DNA genome of phage BA6 is composed of 50,520 bp with a G+C content of 41.77%. It possesses 64 open reading frames relating to phage structure, packaging, host lysis, DNA metabolism, and additional functions. Three tRNAs genes (encoding Pro, Ile and Trp) were detected. Comparison of its genomic features and phylogenetic analysis revealed that phage BA6 is a novel member of the family Podoviridae. This phage may represent a potential therapeutic agent against multidrug-resistant Vibrio parahaemolyticus.