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811200.9930Fate of antibiotic resistance bacteria and genes during enhanced anaerobic digestion of sewage sludge by microwave pretreatment. The fate of antibiotic resistant bacteria (ARB) and antibiotic resistance genes (ARGs) were investigated during the sludge anaerobic digestion (AD) with microwave-acid (MW-H), microwave (MW) and microwave-H2O2-alkaline (MW-H2O2) pretreatments. Results showed that combined MW pretreatment especially for the MW-H pretreatment could efficiently reduce the ARB concentration, and most ARG concentrations tended to attenuate during the pretreatment. The subsequent AD showed evident removal of the ARB, but most ARGs were enriched after AD. Only the concentration of tetX kept continuous declination during the whole sludge treatment. The total ARGs concentration showed significant correlation with 16S rRNA during the pretreatment and AD. Compared with unpretreated sludge, the AD of MW and MW-H2O2 pretreated sludge presented slightly better ARB and ARGs reduction efficiency.201626970692
787710.9926External circuit loading mode regulates anode biofilm electrochemistry and pollutants removal in microbial fuel cells. This study investigated the effects of different external circuit loading mode on pollutants removal and power generation in microbial fuel cells (MFC). The results indicated that MFC exhibited distinct characteristics of higher maximum power density (P(max)) (named MFC-HP) and lower P(max) (named MFC-LP). And the capacitive properties of bioanodes may affect anodic electrochemistry. Reducing external load to align with the internal resistance increased P(max) of MFC-LP by 54.47 %, without no obvious effect on MFC-HP. However, intermittent external resistance loading (IER) mitigated the biotoxic effects of sulfamethoxazole (SMX) (a persistent organic pollutant) on chemical oxygen demand (COD) and NH(4)(+)-N removal and maintained high P(max) (424.33 mW/m(2)) in MFC-HP. Meanwhile, IER mode enriched electrochemically active bacteria (EAB) and environmental adaptive bacteria Advenella, which may reduce antibiotic resistance genes (ARGs) accumulation. This study suggested that the external circuit control can be effective means to regulate electrochemical characteristics and pollutants removal performance of MFC.202439153696
786120.9921The removal of antibiotic resistant bacteria and genes and inhibition of the horizontal gene transfer by contrastive research on sulfidated nanoscale zerovalent iron activating peroxymonosulfate or peroxydisulfate. Antibiotic resistant bacteria (ARB) and the antibiotic resistance genes (ARGs) dissemination via plasmid-mediated conjugation have attracted considerable attentions. In this research, sulfidated nanoscale zerovalent iron (S-nZVI)/peroxymonosulfate (PMS) and S-nZVI/peroxydisulfate (PDS) process were investigated to inactivate ARB (Escherichia coli DH5α with RP4 plasmid, Pseudomonas. HLS-6 contains sul1 and intI1 on genome DNA sequence). S-nZVI/PMS system showed higher efficiency than S-nZVI/PDS on ARB inactivation. Thus, the optimal condition 28 mg/L S-nZVI coupled with 153.7 mg/L (0.5 mM) PMS was applied to remove both intracellular ARGs (iARGs) and ARB. The oxidative damage of ARB cell was systemically studied by cell viability, intracellular Mg(2+) levels, the changes of extracellular and internal structure, integrity of cell walls and membranes and enzymatic activities. S-nZVI/PMS effectively inactivated ARB (~7.32 log) within 15 min. These effects were greatly higher than those achieved individually. Moreover, removal efficiencies of iARGs sul1, intI1 and tetA were 1.52, 1.79 and 1.56 log, respectively. These results revealed that S-nZVI and PMS have a synergistic effect against ARB and iARGs. The regrowth assays illustrated that the ARB were effectively inactivated. By verifying the inhibitory impacts of S-nZVI/PMS treatment on conjugation transfer, this work highlights a promising alternative technique for inhibiting the horizontal gene transfer.202234482079
786030.9920Enhanced removal of antibiotic-resistant bacteria and resistance genes by three-dimensional electrochemical process using MgFe(2)O(4)-loaded biochar as both particle electrode and catalyst for peroxymonosulfate activation. In this study, MgFe(2)O(4)-loaded biochar (MFBC) was used as a three-dimensional particle electrode to active peroxymonosulfate (EC/MFBC/PMS) for the removal of antibiotic-resistant bacteria (ARB) and antibiotic resistance genes (ARGs). The results demonstrated that, under the conditions of 1.0 mM PMS concentration, 0.4 g/L material dosage, 5 V voltage intensity, and MFBC preparation temperature of 600 °C, the EC/MFBC600/PMS system achieved complete inactivation of E. coli DH5α within 5 min and the intracellular sul1 was reduced by 81.5 % after 30 min of the treatment. Compared to EC and PMS alone treatments, the conjugation transfer frequency of sul1 rapidly declined by 92.9 % within 2 min. The cell membrane, proteins, lipids, as well as intracellular and extracellular ARGs in E. coli DH5α were severely damaged by free radicals in solution and intracellular reactive oxygen species (ROS). Furthermore, up-regulation was observed in genes associated with oxidative stress, SOS response and cell membrane permeability in E. coli DH5α, however, no significant changes were observed in functional genes related to gene conjugation and transfer mechanisms. This study would contribute to the underlying of PMS activation by three-dimensional particle electrode, and provide novel insights into the mechanism of ARB inactivation and ARGs degradation under PMS advanced oxidation treatment.202439197284
784840.9920Simultaneous Removal of Antibiotic Resistant Bacteria, Antibiotic Resistance Genes, and Micropollutants by FeS(2)@GO-Based Heterogeneous Photo-Fenton Process. The co-occurrence of various chemical and biological contaminants of emerging concerns has hindered the application of water recycling. This study aims to develop a heterogeneous photo-Fenton treatment by fabricating nano pyrite (FeS(2)) on graphene oxide (FeS(2)@GO) to simultaneously remove antibiotic resistant bacteria (ARB), antibiotic resistance genes (ARGs), and micropollutants (MPs). A facile and solvothermal process was used to synthesize new pyrite-based composites. The GO coated layer forms a strong chemical bond with nano pyrite, which enables to prevent the oxidation and photocorrosion of pyrite and promote the transfer of charge carriers. Low reagent doses of FeS(2)@GO catalyst (0.25 mg/L) and H(2)O(2) (1.0 mM) were found to be efficient for removing 6-log of ARB and 7-log of extracellular ARG (e-ARG) after 30 and 7.5 min treatment, respectively, in synthetic wastewater. Bacterial regrowth was not observed even after a two-day incubation. Moreover, four recalcitrant MPs (sulfamethoxazole, carbamazepine, diclofenac, and mecoprop at an environmentally relevant concentration of 10 μg/L each) were completely removed after 10 min of treatment. The stable and recyclable composite generated more reactive species, including hydroxyl radicals (HO(•)), superoxide radicals (O(2)(• -)), singlet oxygen ((1)O(2)). These findings highlight that the synthesized FeS(2)@GO catalyst is a promising heterogeneous photo-Fenton catalyst for the removal of emerging contaminants.202235759741
793550.9919Removal of antibiotic resistance genes by Cl(2)-UV process: Direct UV damage outweighs free radicals in effectiveness. Antibiotic resistance genes (ARGs) pose significant environmental health problems and have become a major global concern. This study investigated the efficacy and mechanism of the Cl(2)-UV process (chlorine followed by UV irradiation) for removing ARGs in various forms. The Cl(2)-UV process caused irreversible damage to nearly all ARB at typical disinfectant dosages. In solutions containing only extracellular ARGs (eARGs), the Cl₂-UV process achieved over 99.0 % degradation of eARGs. When both eARGs and intracellular ARGs (iARGs) were present, the process reached a 97.2 % removal rate for iARGs. While the abundance of eARGs initially increased due to the release of iARGs from lysed cells during pre-chlorination, subsequent UV irradiation rapidly degraded the released eARGs, restoring their abundance to near-initial levels by the end of the Cl₂-UV process. Analysis of the roles in degrading eARGs and iARGs during the Cl(2)-UV process revealed that UV, rather than free radicals, was the dominant factor causing ARG damage. Pre-chlorination enhanced direct UV damage to eARGs and iARGs by altering plasmid conformation and promoting efficient damage to high UV-absorbing cellular components. Furthermore, no further natural transformation of residual ARGs occurred following the Cl(2)-UV treatment. This study demonstrated strong evidence for the effectiveness of the Cl(2)-UV process in controlling antibiotic resistance.202540048777
789760.9919Enhanced removal of antibiotic and antibiotic resistance genes by coupling biofilm electrode reactor and manganese ore substrate up-flow microbial fuel cell constructed wetland system. Manganese ore substrate up-flow microbial fuel cell constructed wetland (UCW-MFC(Mn)) as an innovative wastewater treatment technology for purifying antibiotics and electricity generation with few antibiotic resistance genes (ARGs) generation has attracted attention. However, antibiotic purifying effects should be further enhanced. In this study, a biofilm electrode reactor (BER) that needs direct current driving was powered by a Mn ore anode (UCW-MFC(Mn)) to form a coupled system without requiring direct-current source. Removal efficiencies of sulfadiazine (SDZ), ciprofloxacin (CIP) and the corresponding ARGs in the coupled system were compared with composite (BER was powered by direct-current source) and anaerobic systems (both of BER and UCW-MFC were in open circuit mode). The result showed that higher antibiotic removal efficiency (94% for SDZ and 99.1% for CIP) in the coupled system was achieved than the anaerobic system (88.5% for SDZ and 98.2% for CIP). Moreover, electrical stimulation reduced antibiotic selective pressure and horizontal gene transfer potential in BER, and UCW-MFC further reduced ARG abundances by strengthening the electro-adsorption of ARG hosts determined by Network analysis. Bacterial community diversity continuously decreased in BER while it increased in UCW-MFC, indicating that BER mitigated the toxicity of antibiotic. Degree of modularity, some functional bacteria (antibiotic degrading bacteria, fermentative bacteria and EAB), and P450 enzyme related to antibiotic and xenobiotics biodegradation genes were enriched in electric field existing UCW-MFC, accounting for the higher degradation efficiency. In conclusion, this study provided an effective strategy for removing antibiotics and ARGs in wastewater by operating a BER-UCW-MFC coupled system.202337437616
785370.9919Natural pyrite and ascorbic acid co-enhance periodate activation for inactivation of antibiotic resistant bacteria and inhibition of resistance genes transmission: A green disinfection process dominated by singlet oxygen. The transmission of antibiotic resistance genes (ARGs) and the propagation of antibiotic resistant bacteria (ARB) threaten public health security and human health, and greener and more efficient disinfection technologies are expected to be discovered for wastewater treatment. In this study, natural pyrite and ascorbic acid (AA) were proposed as environmental-friendly activator and reductant for periodate (PI) activation to inactivate ARB. The disinfection treatment of PI/pyrite/AA system could inactivate 5.62 log ARB within 30 min, and the lower pH and higher PI and natural pyrite dosage could further boost the disinfection efficiency. The (1)O(2) and SO(4)(•-) were demonstrated to be crucial for the inactivation of ARB in PI/pyrite/AA system. The disinfection process destroyed the morphological structure of ARB, inducing oxidative stress and stimulating the antioxidant system. The PI/pyrite/AA system effectively reduced the intracellular and extracellular DNA concentration and ARGs abundance, inhibiting the propagation of ARGs. The presence of AA facilitated the activation of PI with natural pyrite and significantly increased the concentration of Fe(2+) in solution. The reusability of natural pyrite, the safety of the disinfection by-products and the inhibition of ARB regeneration indicated the application potential of PI/pyrite/AA system in wastewater disinfection.202439038380
794080.9918Microplastics affect the ammonia oxidation performance of aerobic granular sludge and enrich the intracellular and extracellular antibiotic resistance genes. Microplastics (MPs) and antibiotic resistance genes (ARGs), as emerging pollutants, are frequently detected in wastewater treatment plants, and their threats to the environment have received extensive attentions. However, the effects of MPs on the nitrification of aerobic granular sludge (AGS) and the spread patterns of intracellular and extracellular ARGs (iARGs and eARGs) in AGS were still unknown. In this study, the responses of AGS to the exposure of 1, 10 and 100 mg/L of typical MPs (polyvinyl chloride (PVC), polyamide (PA), polystyrene (PS) and polyethylene (PE)) and tetracycline were focused on in 3 L nitrifying sequencing batch reactors. 10 mg/L MPs decreased the nitrification function, but nitrification could recover. Furthermore, MPs inhibited ammonia-oxidizing bacteria and enriched nitrite-oxidizing bacteria, leading partial nitrification to losing stability. PVC, PA and PS stimulated the secretion of extracellular polymeric substances and reactive oxygen species. PE had less negative effect on AGS than PVC, PA and PS. The abundances of iARGs and eARGs (tetW, tetE and intI1) increased significantly and the intracellular and extracellular microbial communities obviously shifted in AGS system under MPs stress. Potential pathogenic bacteria might be the common hosts of iARGs and eARGs in AGS system and were enriched in AGS and MPs biofilms.202133387747
785490.9918Removal of antibiotic resistant bacteria and plasmid-encoded antibiotic resistance genes in water by ozonation and electro-peroxone process. The electro-peroxone (EP) process is an electricity-based oxidation process enabled by electrochemically generating hydrogen peroxide (H(2)O(2)) from cathodic oxygen (O(2)) reduction during ozonation. In this study, the removal of antibiotic resistant bacteria (ARB) and plasmid-encoded antibiotic resistance genes (ARGs) during groundwater treatment by ozonation alone and the EP process was compared. Owing to the H(2)O(2)-promoted ozone (O(3)) conversion to hydroxyl radicals (•OH), higher •OH exposures, but lower O(3) exposures were obtained during the EP process than ozonation alone. This opposite change of O(3) and •OH exposures decreases the efficiency of ARB inactivation and ARG degradation moderately during the EP process compared with ozonation alone. These results suggest that regarding ARB inactivation and ARG degradation, the reduction of O(3) exposures may not be fully counterbalanced by the rise of •OH exposures when changing ozonation to the EP process. However, due to the rise of •OH exposure, plasmid DNA was more effectively cleaved to shorter fragments during the EP process than ozonation alone, which may decrease the risks of natural transformation of ARGs. These findings highlight that the influence of the EP process on ARB and ARG inactivation needs to be considered when implementing this process in water treatment.202336738938
7880100.9918The synergistic mechanism of β-lactam antibiotic removal between ammonia-oxidizing microorganisms and heterotrophs. Nitrifying system is an effective strategy to remove numerous antibiotics, however, the contribution of ammonia-oxidizing bacteria (AOB), ammonia-oxidizing archaea (AOA) and heterotrophs for antibiotic removal are still unclear. In this study, the mechanism of β-lactam antibiotic (cefalexin, CFX) removal was studied in a nitrifying sludge system. Results showed that CFX was synergistically removed by AOB (Nitrosomonas, played a major role) and AOA (Candidatus_Nitrososphaera) through ammonia monooxygenase-mediated co-metabolism, and by heterotrophs (Pseudofulvimonas, Hydrogenophaga, RB41, Thauera, UTCFX1, Plasticicumulans, Phaeodactylibacter) through antibiotic resistance genes (ARGs)-encoded β-lactamases-mediated hydrolysis. Regardless of increased archaeal and heterotrophic CFX removal with the upregulation of amoA in AOA and ARGs, the system exhibited poorer CFX removal performance at 10 mg/L, mainly due to the inhibition of AOB. This study provides new reference for the important roles of heterotrophs and ARGs, opening the possibilities for the application of ARGs in antibiotic biodegradation.202336174754
8117110.9917Composting of oxytetracycline fermentation residue in combination with hydrothermal pretreatment for reducing antibiotic resistance genes enrichment. Hydrothermal pretreatment can efficiently remove the residual antibiotics in oxytetracycline fermentation residue (OFR), but its effect on antibiotic resistance genes (ARGs) during composting remains unclear. This study compared the shifts in bacterial community and evolutions in ARGs and integrons during different composting processes of OFRs with and without hydrothermal pretreatment. The results demonstrated that hydrothermal pretreatment increased the bacterial alpha diversity at the initial phase, and increased the relative abundances of Proteobacteria and Actinobacteria but decreased that of Bacteroidetes at the final phase by inactivating mycelia and removing residual oxytetracycline. Composting process inevitably elevated the abundance and relative abundance of ARGs. However, the increase in ARGs was significantly reduced by hydrothermal pretreatment, because the removal of oxytetracycline decreased their potential host bacteria and inhibited their horizontal gene transfer. The results demonstrated that hydrothermal pretreatment is an efficient strategy to reduce the enrichment of ARGs during the OFR composting.202033099099
7831120.9917Integration of nanowire-confined electroporation of antibiotic-resistant bacteria and electroactivation of peracetic acid for eliminating intracellular resistance genes. Antimicrobial resistance is one of the most substantial challenges for global public health. To address the inefficient elimination of intracellular resistance genes (i-ARGs) in antibiotic-resistant bacteria (ARB) by peracetic acid (PAA) oxidation, we developed an integration strategy (NW-EP/EA) of nanowire-confined electroporation (NW-EP) of ARB cells and nanowire-confined electroactivation (NW-EA) of PAA with a sequential oxidation-reduction process. The locally enhanced electric field and electrocatalytic activity over NW tips prompted the formation of electroporation pores on ARB cells and the generation of reactive ⋅OH and RO⋅ radicals by PAA electroactivation. The NW-EP/EA with Pd-coated TiO(2)NW cathode with atomic H* evolution exhibited 0.6 -2.8-log higher i-ARG removal than the pristine TiO(2)NW cathode, especially achieving ∼5.0-log i-ARG removal (99.999 %) at 4.0 V and 2.0 mM PAA with ∼4.1-log synergistic effect and ∼10 times lower energy consumption as compared with the individual NW-EP (∼0.32-log and 52.1 %) and PAA (∼0.56-log and 74.4 %). For the sequential oxidation-reduction process, the electrooxidative activation of PAA on TiO(2)NW anode produced H(+) ions, ⋅OH and RO⋅ radicals for enlarging electroporation pores, and the generated H(+) ions promoted the evolution of atomic H* and electroreduction of PAA on subsequent Pd-TiO(2)NW cathode for further facilitating ARB cell damages, i-ARG leakage and degradation. The effective i-ARGs removal and HGT inhibition in tap water suggested the great application potentials of NW-EP/EA in the control of ARGs dissemination risks in drinking water.202540907311
8487130.9917Mechanisms of nano zero-valent iron in enhancing dibenzofuran degradation by a Rhodococcus sp.: Trade-offs between ATP production and protection against reactive oxygen species. Nano zero-valent iron (nZVI) can enhance pollutants biodegradation, but it displays toxicity towards microorganisms. Gram-positive (G(+)) bacteria exhibit greater resistance to nZVI than Gram-negative bacteria. However, mechanisms of nZVI accelerating pollutants degradation by G(+) bacteria remain unclear. Herein, we explored effects of nZVI on a G(+) bacterium, Rhodococcus sp. strain p52, and mechanisms by which nZVI accelerates biodegradation of dibenzofuran, a typical polycyclic aromatic compound. Electron microscopy and energy dispersive spectroscopy analysis revealed that nZVI could penetrate cell membranes, which caused damage and growth inhibition. nZVI promoted dibenzofuran biodegradation at certain concentrations, while higher concentration functioned later due to the delayed reactive oxygen species (ROS) mitigation. Transcriptomic analysis revealed that cells adopted response mechanisms to handle the elevated ROS induced by nZVI. ATP production was enhanced by accelerated dibenzofuran degradation, providing energy for protein synthesis related to antioxidant stress and damage repair. Meanwhile, electron transport chain (ETC) was adjusted to mitigate ROS accumulation, which involved downregulating expression of ETC complex I-related genes, as well as upregulating expression of the genes for the ROS-scavenging cytochrome bd complex and ETC complex II. These findings revealed the mechanisms underlying nZVI-enhanced biodegradation by G(+) bacteria, offering insights into optimizing bioremediation strategies involving nZVI.202539549579
7851140.9916Breaking antibiotic resistance: Sunlight-powered calcium peroxide for dual bactericidal and genetic elimination. Antibiotic-resistant bacteria (ARB) and associated antibiotic resistance genes (ARGs) have emerged as critical waterborne contaminants, posing serious public health risks. This study proposes a disinfection strategy through sunlight powered calcium peroxide (CaO(2)) treatment that simultaneously inactivates ARB and degrades ARGs in aquatic environments. Solar irradiation combined with CaO(2) (3.0 mM) activates dual mechanisms: alkaline-driven microbial inactivation (pH increase from 6.4 to 8.2 within 30 min) and ROS-mediated oxidative damage (ROS: (•)OH, H(2)O(2), (1)O(2) and O(2)(•-)), achieving complete 5-log inactivation of tetracycline and sulfonamides-resistant E. coli (TSRE). ARGs (tetA and sul2) showed 70-80 % reduction in absolute abundance, although the log removal did not exceed 1-log. Compared to sunlight alone, the addition of CaO(2) significantly enhanced disinfection efficiency. Alkaline and ROS-induced oxidative stress caused membrane lipid breakdown, protein denaturation, and suppression of antioxidant enzymes, along with DNA damage, lipid peroxidation, and enzyme inactivation. These effects increased membrane permeability, impaired bacterial recovery by downregulating DNA repair genes, and disrupted cellular integrity, ultimately limiting ARGs persistence. These findings highlight the synergistic effect of alkaline and oxidative stress in effectively inactivating ARB and degrading ARGs, positioning sunlight powered CaO(2) as a promising, highly efficient disinfection strategy for environmental water treatment.202540876436
7911150.9916Biochar induced inhibitory effects on intracellular and extracellular antibiotic resistance genes in anaerobic digestion of swine manure. Distribution of intracellular (iARGs) and extracellular ARGs (eARGs) in manure anaerobic digestion (AD) process coupled with two types of biochar (BC and BP) were investigated. And the effects of biochar on the conjugation transfer of ARGs were explored by deciphering the interaction of biochar with bacterial stress responses, physiological metabolism and antibiotic resistances. Results showed that AD process could effectively remove all the detected eARGs with efficiency of 47.4-98.2%. The modified biochar (BP) with larger specific surface area (SSA) was propitious to decrease the absolute copy number of extracellular resistance genes. AD process could effectively remove iARGs by inhibiting the growth of host bacteria. The results of structural equation models (SEM) indicated that biochar put indirect influences on the fate of ARGs (λ = -0.23, P > 0.05). Analysis on oxidative stress levels, antioxidant capacity, DNA damage-induced response (SOS) response and energy generation process demonstrated that biochar induced the oxidative stress response of microorganisms and enhanced the antioxidant capacity of bacteria. The elevated antioxidant capacity negatively affected SOS response, amplified cell membrane damage and further weakened the energy generation process, resulted in the inhibition of horizontal transfer of ARGs.202235609652
7910160.9915Tetracycline degradation by a mixed culture of halotolerant fungi-bacteria under static magnetic field: Mechanism and antibiotic resistance genes transfer. Efficient antibiotics removal lowers the transmission risk of antibiotic resistance genes (ARGs). However, low efficiency limits the application of biological methods for antibiotics removal. Herein, a mixed culture of halotolerant fungi-bacteria was used for treatment of saline wastewater containing tetracycline (TC). Furthermore, static magnetic field (SMF) was used to increase TC removal. The study examined the effectiveness of SMF in removing antibiotics from saline wastewater and the associated risk of ARGs transmission. The results demonstrated that the application of a 40 mT SMF significantly improved the TC removal efficiency by 37.09 %, compared to the control (SMF=0) The TC was mainly removed through biodegradation and adsorption. In biodegradation, SMF enhanced electron transport system activity, and activities of lignin-degrading enzymes which led to higher TC biodegradation. The activity of lactate dehydrogenase and malondialdehyde decreased, lowering the damage of microbial cell membranes by TC. During the adsorption process, higher generation of extracellular polymeric substances was observed under SMF, which caused an increase in TC removal via adsorption. Microbial community analysis revealed that SMF facilitated the enrichment of TC-degrading microorganisms. Under SMF, vertical gene transfer of ARGs increased, while horizontal gene transfer risk decreased due to a reduction in mobile genetic elements (intl1) abundance. This study demonstrates that SMF is a promising strategy for enhancing TC removal efficiency, providing a basis for improved antibiotic wastewater management.202540199074
7859170.9915Abatement of antibiotics and resistance genes during catalytic ozonation enhanced sludge dewatering process: Synchronized in volume and hazardousness reduction. Based on the efficiency of the catalytic ozonation techniques (HDWS+O(3) and MnFe(2)O(4) @SBC+O(3)) in enhancing the sludge dewaterability, the effectiveness in synchronized abatement antibiotics and antibiotic resistance genes (ARGs) was conducted to determine. The results revealed that catalytic ozonation conditioning altered the distribution of target antibiotics (tetracycline (TC), oxytetracycline (OTC), norfloxacin (NOR), ofloxacin (OFL)) in the dewatered filtrate, the dewatered sludge cake and the extra-microcolony/cellular polymers (EMPS/ECPS) layers, achieving the redistribution from solid-phase adsorption to liquid-phase dissolution. The total degradation rate was over 90% for TC and OTC, 72-78% for NOR and OFL; the abatement efficiency of eleven ARGs reached 1.47-3.01 log and 1.64-3.59 log, respectively, and more than four eARGs were eliminated. The effective abatement of the absolute abundance of Mobile genetic elements (MGEs) (0.91-1.89 log) demonstrated that catalytic ozonation conditioning could also significantly inhibit horizontal gene transfer (HGT). The abundance of resistant bacteria was greatly reduced and the signal transduction of the typical ARGs host bacteria was inhibited. The highly reactive oxidation species (ROS) generated were responsible for the abatement of antibiotics and ARGs. These findings provided new insights into the sludge conditioning for ideal and synchronized reduction in volume and hazardousness by catalytic ozonation processes in sludge treatment.202437944236
7858180.9914Photocatalytic Reactive Ultrafiltration Membrane for Removal of Antibiotic Resistant Bacteria and Antibiotic Resistance Genes from Wastewater Effluent. Biological wastewater treatment is not effective in removal of antibiotic resistant bacteria (ARB) and antibiotic resistance genes (ARGs). In this study, we fabricated a photocatalytic reactive membrane by functionalizing polyvinylidene fluoride (PVDF) ultrafiltration (UF) membrane with titanium oxide (TiO(2)) nanoparticles for the removal of ARB and ARGs from a secondary wastewater effluent. The TiO(2)-modified PVDF membrane provided complete retention of ARB and effective photocatalytic degradation of ARGs and integrons. Specifically, the total removal efficiency of ARGs (i.e., plasmid-mediated floR, sul1, and sul2) with TiO(2)-modified PVDF membrane reached ∼98% after exposure to UV irradiation. Photocatalytic degradation of ARGs located in the genome was found to be more efficient than those located in plasmid. Excellent removal of integrons (i.e., intI1, intI2, and intI3) after UV treatment indicated that the horizontal transfer potential of ARGs was effectively controlled by the TiO(2) photocatalytic reaction. We also evaluated the antifouling properties of the TiO(2)-UF membrane to demonstrate its potential application in wastewater treatment.201829984583
7893190.9914Removal of ofloxacin and inhibition of antibiotic resistance gene spread during the aerobic biofilm treatment of rural domestic sewage through the micro-nano aeration technology. Micro-nano aeration (MNA) has great potential for emerging contaminant removal. However, the mechanism of antibiotic removal and antibiotic resistance gene (ARG) spread, and the impact of the different aeration conditions remain unclear. This study investigated the adsorption and biodegradation of ofloxacin (OFL) and the spread of ARGs in aerobic biofilm systems under MNA and conventional aeration (CVA) conditions. Results showed that the MNA increased OFL removal by 17.27 %-40.54 % and decreased total ARG abundance by 36.37 %-54.98 %, compared with CVA. MNA-induced biofilm rough morphology, high zeta potential, and reduced extracellular polymeric substance (EPS) secretion enhanced OFL adsorption. High dissolved oxygen and temperature, induced by MNA-enriched aerobic bacteria and their carrying OFL-degrading genes, enhanced OFL biodegradation. MNA inhibited the enrichment of ARG host bacteria, which acquired ARGs possibly via horizontal gene transfer (HGT). Functional profiles involved in the HGT process, including reactive oxygen species production, membrane permeability, mobile genetic elements (MGEs), adenosine triphosphate synthesis, and EPS secretion, were down-regulated by MNA, inhibiting ARG spread. Partial least-squares path modeling revealed that MGEs might be the main factor inhibiting ARG spread. This study provides insights into the mechanisms by which MNA enhances antibiotic removal and inhibits ARG spread in aerobic biofilm systems.202539733752