INTENSIVELY - Word Related Documents




#
Rank
Similarity
Title + Abs.
Year
PMID
012345
690500.9944The hot air circulation ventilation composting system removes antibiotic resistance genes through competitive inhibition by core bacteria. Livestock manure is a significant reservoir of antibiotic resistance genes (ARGs). Aerobic composting technology can produce mature compost while effectively removing ARGs. In this study, we developed an energy-saving and emission-reducing hot air circulating ventilated composting technology (HACV), which had no adverse effects on the composting process or compost maturity. The HACV composting altered bacterial communities, primarily driven by heterogeneous selection among deterministic factors (65 %). Specifically, it increased the complexity of bacterial networks and promoted the colonization of high-temperature-tolerant bacteria, such as Erysipelothrix, Oceanobacillus and unclassified_f_Bacillaceae. Topological analysis revealed that core bacteria primarily functioned as connectors in composting, serving as important ARGs hosts and facilitating their spread in conventional composting. Among these, a core pathogenic bacterium (Corynebacterium) carried and transmitted ARGs with higher risks. In contrast, although the number of core bacteria (Bacillus, Oceanobacillus, Caldicoprobacter, Saccharomonospora, and Lactobacillus) increased during HACV composting, these bacteria were not potential hosts of the target ARGs. This contributed to the removal of aadE by 80.49 %. Consequently, compared to conventional composting, HACV composting was more effective at controlling risky ARGs, particularly aac(6')-Ib-cr and sul1. Furthermore, the ARGs removal mechanism primarily involved inhibiting horizontal gene transfer (HGT) in HACV composting, attributed to competition between core bacteria and ARGs hosts. In summary, HACV composting effectively promotes ARGs removal and reduces the risk of bacterial resistance. ENVIRONMENTAL IMPLICATION: In this study, we developed an energy-saving and emission-reducing hot air circulation ventilation composting technology (HACV), which effectively removes antibiotic resistance genes (ARGs). The HACV system maintained composting efficiency and maturity while driving bacterial community succession through deterministic processes (heterogeneous selection). HACV composting increased the colonization of core bacteria in the microbial network. Acting as connectors, the core bacteria are not hosts of ARGs in the HACV system, inhibiting horizontal gene transfer (HGT) and remove ARGs through competition with host bacteria.202540682888
799010.9943Calcined Eggshell Waste for Mitigating Soil Antibiotic-Resistant Bacteria/Antibiotic Resistance Gene Dissemination and Accumulation in Bell Pepper. The combined accumulation of antibiotics, heavy metals, antibiotic-resistant bacteria (ARB)/antibiotic resistance genes (ARGs) in vegetables has become a new threat to human health. This is the first study to investigate the feasibility of calcined eggshells modified by aluminum sulfate as novel agricultural wastes to impede mixed contaminants from transferring to bell pepper (Capsicum annuum L.). In this work, calcined eggshell amendment mitigated mixed pollutant accumulation in bell pepper significantly, enhanced the dissipation of soil tetracycline, sulfadiazine, roxithromycin, and chloramphenicol, decreased the water-soluble fractions of antibiotics, and declined the diversity of ARB/ARGs inside the vegetable. Moreover, quantitative polymerase chain reaction analysis detected that ARG levels in the bell pepper fruits significantly decreased to 10(-10) copies/16S copies, indicating limited risk of ARGs transferring along the food chain. Furthermore, the restoration of soil microbial biological function suggests that calcined eggshell is an environmentally friendly amendment to control the dissemination of soil ARB/ARGs in the soil-vegetable system.201627333280
806720.9940Enhanced control of sulfonamide resistance genes and host bacteria during thermophilic aerobic composting of cow manure. Traditional composting has already shown a certain effect in eliminating antibiotic residues, antibiotic-resistant bacteria (ARBs), and antibiotic resistance genes (ARGs). It is worth noting that the rebounding of ARGs and the succession of the bacterial community during conventional aerobic composting are still serious threats. Considering the probable risk, improved and adaptable technologies are urgently needed to control antibiotic resistance efficiently. This study monitored how thermophilic aerobic composting affected the ARGs, as well as the bacterial diversity during the composting of cow manure spiked with sulfamethoxazole (SMX) at different concentrations. Results showed that the degradation of SMX was enhanced during thermophilic aerobic composting (control > SMX25 > SMX50 > SMX100) and was no longer detected after 20 days of composting. High temperature or heat significantly stimulated the rebounding of certain genes. After 35 days, the abundance of detected genes (sul2, sulA, dfrA7, and dfrA1) significantly decreased (p < 0.05) in control and antibiotic-spiked treatments, except for sul1. The addition of three concentrations of SMX elicited a sharp effect on bacterial diversity, and microbial structure in SMX25 led to significant differences with others (p < 0.05). The network analysis revealed more rigorous interactions among ARGs and abundant genera, suggesting that the host of ARGs potentially increased at low concentrations of SMX. Especially, genera g_norank_f__Beggiatoaceae, Ruminiclostridium, Caldicoprobacter, g_norank_o_MBA03, Hydrogenispora, and Ruminiclostridium_1 were major potential hosts for sul1. In conclusion, the rebounding of ARGs could be intermitted partially, and more efficient control of antibiotic resistance could be achieved in the thermophilic composting compared to conventional methods.202133582626
810230.9940Plants inhibit the relative abundance of sulfonamide resistance genes and class 1 integron by influencing bacterial community in rhizosphere of constructed wetlands. Antibiotic resistance genes (ARGs) commonly detected in wastewater can potentially lead to a health crisis. Constructed wetlands (CWs) remove ARGs and sulfonamides (SAs) from wastewater, but the importance of plants in the process is seldom reported. We compared the effect of three wetland plant species (Cyperus alternifolius, Juncus effuses, and Cyperus papyrus), sample distance from the root, and SA presence on the environmental abundance of class 1 integron (intI1) and SA resistance genes (sul) using specially designed CW rhizoboxes. Quantitative polymerase chain reaction revealed that the relative abundance of the target genes in planted CWs, especially in C. alternifolius planted CWs, was significantly lower than that in unplanted CWs (P < 0.05). The substrate in the rhizosphere or near-/moderate-rhizosphere (closest to the root) showed the lowest average relative abundance of the target genes, while the bulk substrate (without the root) showed the highest abundance of these genes, irrespective of the planted species. Further, the influence of plants was more evident after 8 weeks of wastewater treatment. The trend was the same in SA-treated and untreated groups, although the relative abundance of the target genes was significantly higher in the former (P < 0.05). The weaker correlation between the intI1 and sul genes in the rhizosphere and near-/moderate-rhizosphere in comparison to the bulk substrate in the SA group suggested that the risk of horizontal gene transfer was probably higher in the bulk substrate and unplanted CW. A partial least-squares path model revealed that dissolved organic carbon and oxygen content significantly influenced SA concentration, microbial community, and intI1 genes, and then shaping the sul genes together. Finally, redundancy analysis suggested that abundance of sul genes was influenced by bacteria enriched in the bulk substrate and unplanted CWs. The findings provide new insights into the importance for controlling risk of ARGs by wetland plants.202235181368
690740.9939Deciphering the impact of organic loading rate and digestate recirculation on the occurrence patterns of antibiotics and antibiotic resistance genes in dry anaerobic digestion of kitchen waste. Organic loading rate (OLR) is crucial for determining the stability of dry anaerobic digestion (AD). Digestate recirculation contributes to reactor stability and enhances methane production. Nevertheless, the understanding of how OLR and digestate recirculation affect the abundance and diversity of antibiotics and antibiotic resistance genes (ARGs), as well as the mechanisms involved in the dissemination of ARGs, remains limited. This study thoroughly investigated this critical issue through a long-term pilot-scale experiment. The metabolome analyses revealed the enrichment of various antibiotics, such as aminoglycoside, tetracycline, and macrolide, under low OLR conditions (OLR ≤ 4.0 g·VS/L·d) and the reactor instability. Antibiotics abundance decreased by approximately 19.66-31.69 % during high OLR operation (OLR ≥ 6.0 g·VS/L·d) with digestate recirculation. The metagenome analyses demonstrated that although low OLR promoted reactor stability, it facilitated the proliferation of antibiotic-resistant bacteria, such as Pseudomonas, and triggered functional profiles related to ATP generation, oxidative stress response, EPS secretion, and cell membrane permeability, thereby facilitating horizontal gene transfer (HGT) of ARGs. However, under stable operation at an OLR of 6.0 g·VS/L·d, there was a decrease in ARGs abundance but a notable increase in human pathogenic bacteria (HPB) and mobile genetic elements (MGEs). Subsequently, during reactor instability, the abundance of ARGs and HPB increased. Notably, during digestate recirculation at OLR levels of 6.0 and 7.0 g·VS/L·d, the process attenuated the risk of ARGs spread by reducing the diversity of ARGs hosts, minimizing interactions among ARGs hosts, ARGs, and MGEs, and weakening functional profiles associated with HGT of ARGs. Overall, digestate recirculation aids in reducing the abundance of antibiotics and ARGs under high OLR conditions. These findings provide advanced insights into how OLR and digestate recirculation affect the occurrence patterns of antibiotics and ARGs in dry AD.202438968733
785550.9939Combat against antibiotic resistance genes during photo-treatment of magnetic Zr-MOFs@Layered double hydroxide heterojunction: Conjugative transfer risk mitigating and bacterial inactivation. The dissemination of antimicrobial resistance (AMR) in wastewater treatment poses a severe threat to the global ecological environment. This study explored the effectiveness of photocatalysis in inactivating antibiotic resistant bacteria (ARB) and quantitatively clarified the inhibiting rate of the transfer of antibiotics resistance genes (ARGs). Herein, the magnetic heterojunction as UiO-66-NH(2)@CuFe LDH-Fe(3)O(4) (UN-66@LDH-Fe) effectively facilitated the electron-hole separation and accelerated the photogenerated charge transfer, thereby guaranteeing the stable practical application in aeration tanks. Notably, the internal electric field of heterogeneous photocatalyst resulted in significant increase of ARGs inactivation, achieving 5.63 log of ARB, 3.66 log of tetA and 3.57 log of Ampr genes were photodegraded under optimal reaction conditions within 6 h. Based on the complex microbial and molecular mechanism of multiple-ARB communities inactivation in photo-treatment, the photogenerated reactive oxygen species (ROSs, ·OH and ·O(2)(-)) effectively destroyed bacterial membrane protein, thereby the intracellular ROSs and redox cycles further induced oxidative stress, attributing to the abundance reduction of ARGs and their host bacteria. Moreover, long-term (7 days) continuous operation preliminarily verified the practical potential in reducing AMR spread and developing wastewater treatment efficacy. Overall, this study presented an advantageous synergistic strategy for mitigating the AMR-associated environmental risk in wastewater treatment.202540188541
792960.9938Size-dependent effects of microplastics on antibiotic resistance genes fate in wastewater treatment systems: The role of changed surface property and microbial assemblages in a continuous exposure mode. Microplastics (MPs) were continuously transported to wastewater treatment systems and accumulated in sludge constantly, potentially affecting systems function and co-occurrent contaminants fate. However, previous studies were based on acute exposure of MPs, which could not reflect the dynamics of MPs accumulation. Herein, this study firstly raised a more realistic method to evaluate the practical impacts of MPs on systems purification efficiency and antibiotic resistance genes (ARGs) fate. Continuous exposure of MPs did not pose negative effects on nutrients removal, but significantly changed the occurrence patterns of ARGs. ARGs abundances increased by 42.8 % and 54.3 % when exposed to millimeter-size MPs (mm-MPs) polyamide and polyethylene terephthalate, but increased by 31.3 % and 39.4 % to micron-size MPs (μm-MPs), respectively. Thus, mm-MPs posed severer effects on ARGs than μm-MPs. Further, mm-MPs surface properties were obviously altered after long-term exposure (higher specific surface area and O-containing species), which benefited microbes attachment. More importantly, more taxa linkages and changed topological properties (higher average degree and average weight) of co-occurrent network were observed in sludge with mm-MPs than with μm-MPs, as well as totally different potential host bacteria of ARGs. Rough surface of MPs and closer relations between ARGs and bacteria taxa contributed to the propagation of ARGs, which accounted for the observed higher ARGs abundances of mm-MPs. This study demonstrated that long-term accumulation of MPs in wastewater treatment systems affected ARGs fate, and mm-MPs caused severer risk due to their enrichment of ARGs. The results would promote the understanding of MPs real environmental behavior and influences.202236037899
692170.9938Impacts of Chemical and Organic Fertilizers on the Bacterial Communities, Sulfonamides and Sulfonamide Resistance Genes in Paddy Soil Under Rice-Wheat Rotation. The responses of sulfonamides, sulfonamide-resistance genes (sul) and soil bacterial communities to different fertilization regimes were investigated by performing a field experiment using paddy soil with no fertilizer applied, chemical fertilizer applied, organic fertilizer applied, and combination of chemical and organic fertilizer applied. Applying organic fertilizer increased the bacterial community diversity and affected the bacterial community composition. Eutrophic bacteria (Bacteroidetes, Gemmatimonadetes, and Proteobacteria) were significantly enriched by applying organic fertilizer. It was also found organic fertilizer application increased sulfamethazine content and the relative abundances of sul1 and sul2 in the soil. In contrast, applying chemical fertilizer significantly increased the abundance of Nitrospirae, Parcubacteria, and Verrucomicrobia and caused no obvious changes on sul. Correlation analysis indicated that sul enrichment was associated with the increases in sulfamethazine content and potential hosts (e.g., Novosphingobium and Rhodoplanes) population. The potential ecological risks of antibiotics in paddy soil with organic fertilizer applied cannot be ignored.202236547725
855880.9937Mitigating the vertical migration and leaching risks of antibiotic resistance genes through insect fertilizer application. The leaching and vertical migration risks of antibiotic resistance genes (ARGs) from fertilized soil to groundwater poses a significant threat to ecological and public safety. Insect fertilizer, particularly black soldier fly organic fertilizer (BOF), renowned for its minimal antibiotic resistance, emerge as a promising alternative for sustainable agricultural fertilization. This study employs soil-column leaching experiments to evaluate the impact of BOF on the leaching behavior of ARGs. Our results reveal that BOF significantly reduces the leaching risks of ARGs by 22.1 %-49.3 % compared to control organic fertilizer (COF). Moreover, BOF promotes the leaching of beneficial Bacillus and, according to random forest analysis, is the most important factor in predicting ARG profiles (3.02 % increase in the MSE). Further network analysis and mantel tests suggest that enhanced nitrogen metabolism in BOF leachates could foster Bacillus biofilm formation, thereby countering antibiotic-resistant bacteria (ARB) and mitigating antibiotic resistance. In addition, linear regression analysis revealed that Bacillus biofilm-associated genes pgaD (biofilm PGA synthesis protein), slrR (biofilm formation regulator), and kpsC (capsular polysaccharide export protein) were identified as pivotal in the elimination of ARGs, which can serve as effective indicators for assessing antibiotic resistance in groundwater. Collectively, this study demonstrates that BOF as an environmentally friendly fertilizer could markedly reduce the vertical migration risks of ARGs and proposes Bacillus biofilm formation related genes as reliable indicators for monitoring antibiotic resistance in groundwater.202540086570
789690.9937Accumulation of sulfonamide resistance genes and bacterial community function prediction in microbial fuel cell-constructed wetland treating pharmaceutical wastewater. Microbial fuel cell constructed wetlands (CW-MFCs) with different circuit operation conditions and hydraulic retention time (HRT) were constructed to evaluate their ability to remove and accumulate pharmaceutical and personal care products (PPCPs) (sulfadiazine (SDZ), carbamazepine (CBZ), naproxen (NPX) and ibuprofen (IBP)) during four months running process. The abundance level of corresponding sulfonamide antibiotic resistance genes (ARGs) was also investigated. The results showed that closed circuit operation of CW-MFC contributed to the decrease in mass loading of COD, NH(4)(+)-N, PPCPs, and wastewater toxicity in the effluent. Additionally, closed circuit operation with low HRT contributed to enhancing selected PPCP mass accumulation on electrodes by electro-adsorption, and thus the higher sulfonamide ARG abundance was detected in the electrodes and effluent. Moreover, the composition of bacteria was greatly influenced by the mass accumulation of PPCPs revealed by redundancy analysis results. Procrustes analysis results further demonstrated that bacterial community contributed greatly to the ARGs profiles. Therefore, ARGs with their host bacteria revealed by network analysis were partially deposited on electrode substrates, and thus ARGs were effectively accumulated on electrodes. Function analysis of the bacterial community from PICRUSt predicted metagenomes revealed that closed circuit mode enhanced the abundances of the function genes of metabolic and the multiple ARGs, suggesting that closed circuit operation exhibited positive effects on metabolic process and ARG accumulation in CW-MFC system.202031995737
8592100.9937Effects of persulfate treatment on the fates of antibiotic resistance genes in waste activated sludge fermentation process and the underlying mechanism. The occurrence of antibiotic resistance genes (ARGs) in waste activated sludge (WAS) fermentation was investigated with persulfate (PS)-based treatment. ARGs affiliated with multidrug (mexP), macrolide (bla(OXA-129)), tetracycline (tetB), sulfonamide (sul1), and vancomycin (vanRG) types were significantly decreased by PS/Fe treatment. Mechanistic investigations revealed that PS/Fe possessed oxidating potential and exhibited devastating effects on WAS fermentation. First, PS/Fe promoted cell structure damage, which facilitated ARGs release from potential hosts. A co-occurrence network analysis indicated that Fe/PS suppressed the proliferation of potential host bacteria. In addition, the PS/Fe treatment induced the decreased abundance of certain functional genes involved in pathways associated with ARGs dissemination. Finally, variation partitioning analysis demonstrated that the microbial community structure exhibited more vital effects on ARGs fates than physicochemical factors (i.e., pH and ORP) and gene expression (i.e., two-component system). This work provided a deeper understanding of the critical factors used to determine ARGs fates during WAS fermentation.202234864181
7937110.9937Effects of oxytetracycline on variation in intracellular and extracellular antibiotic resistance genes during swine manure composting. This research aimed to investigate the alterations in extracellular (eARGs) and intracellular (iARGs) antibiotic resistance genes in response to oxytetracycline (OTC), and unravel the dissemination mechanism of ARGs during composting. The findings revealed both low (L-OTC) and high contents (H-OTC) of OTC significantly enhanced absolute abundance (AA) of iARGs (p < 0.05), compared to CK (no OTC). Composting proved to be a proficient strategy for removing eARGs, while AA of eARGs was significantly enhanced in H-OTC (p < 0.05). OTC resulted in an increase in AA of mobile genetic elements (MGEs), ATP levels, antioxidant and DNA repair enzymes in bacteria in compost product. Structural equation model further demonstrated that OTC promoted bacterial DNA repair and antioxidant enzyme activities, altered bacterial community and enhanced MGEs abundance, thereby facilitating iARGs dissemination. This study highlights OTC can increase eARGs and iARGs abundance, underscoring the need for appropriate countermeasures to mitigate potential hazards.202438036151
8062120.9937Nanoscale zero-valent iron inhibits the horizontal gene transfer of antibiotic resistance genes in chicken manure compost. Livestock manure has been identified as a significant hotspot for antibiotic resistance genes (ARGs). However, the impact of nanoscale zero-valent iron (nZVI) on the fate of ARGs during livestock manure composting remains poorly understood. Here, we investigated the evolution of ARGs in chicken manure compost exposed to 100 and 600 mg kg(-1) nZVI. The results showed that nZVI addition reduced the concentration of some antibiotics such as doxycycline and sulfamethoxazole. Furthermore, nZVI addition decreased the abundances of most ARGs at the end of composting, but nZVI dosage did not have any significant effect. The abundances of the dominant ARGs (sul1 and sul2) were significantly correlated to the class 1 integron-integrase gene (intI1). A network analysis revealed that the genera Bacteroides, Bacillus, Corynebacterium, Thiopseudomonas and Pseudomonas were the main potential hosts for multiple ARGs, and the decreased abundance of these bacteria contributed to the removal of ARGs. Structural equation models demonstrated that the reduction in intI1 played a predominant role in ARG removal. The nZVI also had direct effects on the intI1 abundance. These findings suggest that the addition of nZVI is a promising strategy to minimize ARG release in chicken manure compost.202234416685
8065130.9937Synergistic enhancement effect of straw-earthworms in the reduction of sulfamethoxazole and antibiotic resistance genes. Soil antibiotic pollution is a global concern. It has been confirmed that straw or earthworm can enhance microbial degradation of antibiotics in soil. However, in the C/N transformation processes of soil ecosystems, straw and earthworms are closely interconnected. Whether their interaction can further enhance microbial degradation of antibiotic pollution and the underlying mechanisms remain to be explored. This study conducted a 90 days co-incubation experiment with four treatments: straw + earthworms + sulfamethoxazole (RS-EW-SMX), straw + SMX (RS-SMX), earthworms + SMX (EW-SMX), and SMX alone (SMX). Residual SMX, its degradation intermediates, and microbial communities were monitored at multiple timepoints. Results indicated an exponential decline in SMX degradation rates across treatments. By day 90, SMX was nearly completely degraded in all treatment groups. However, the combined effect of straw and earthworms significantly enhanced the degradation efficiency of SMX. During the rapid degradation phase, SMX in above four treatments decreased from 20.0 mg kg(-1) to 0.93, 1.88, 5.26 and 7.02 mg kg(-1), respectively at day 10. Furthermore, the RS-EW-SMX treatment promoted SMX transformation into low-molecular-weight intermediates and increased the relative abundance of SMX-degrading bacteria by 1.35, 2.01, and 2.17-fold compared to RS-SMX, EW-SMX, and SMX, respectively. SMX degradation efficiency exhibited a strong positive linear correlation with the relative abundance of degrading bacteria across all treatments (R(2) = 0.961). Concurrently, analysis revealed that straw presence facilitated the targeted enrichment of SMX-degrading bacteria within the earthworm gut, concomitant with a reduction in associated antibiotic resistance genes (ARGs). This synergistic interaction between straw and earthworms, mediated through the gut microbiome and carbon utilization, constitutes a primary mechanism underpinning the accelerated SMX degradation observed. These findings reveal a novel macrofauna-plant residues interaction mechanism for improved in situ antibiotic bioremediation, providing practical solutions for soil pollution mitigation.202540914087
6929140.9937Root exudates regulate soil antibiotic resistance genes via rhizosphere microbes under long-term fertilization. Organic fertilizer application promotes the prevalence of antibiotic resistance genes (ARGs), yet the factors driving temporal differences in ARG abundance under long-term organic fertilizer application remain unclear. This study investigated the temporal dynamics of ARG diversity and abundance in both bulk and rhizosphere soils over 17 years (2003-2019), and explored microbial evolution strategies, ARG hosts succession and the influence of root exudates on ARGs regulation. The results showed that the ARGs abundance in rhizosphere soil was lower than that in bulk soil under long-term fertilization, and ARGs abundance exhibited a decrease and then remained stable in rhizosphere soil over time. There was a strong association between host bacteria and dominant ARGs (p < 0.05). Structural equations demonstrated that bacterial community had a most pronounced influence on ARGs (p < 0.05), and metabolites exhibited an important mediation effect on bacterial community (p < 0.05), thereby impacting ARGs. The metabolome analysis evidenced that significant correlations were found between defensive root exudates and most ARGs abundance (p < 0.05), like, luteolin-7-glucoside was negatively correlated with tetA(58). These findings provide deeper insights into the dynamics of soil ARGs under long-term fertilization, and identify critical factors that influence ARGs colonization in soils, providing support for controlling the spread of ARGs in agriculture soils.202539700687
8097150.9937Fate of antibiotic resistance genes in farmland soil applied with three different fertilizers during the growth cycle of pakchoi and after harvesting. The increasing prevalence of antibiotic resistance genes (ARGs) in the soil environment poses a serious threat to crop safety and even public health. In this study, the fate of ARGs in the soil was investigated during the growth period of pakchoi and after harvesting with the application of different kinds of fertilizers. The result showed that increasing rate of soil ARGs during the growth period of pakchoi followed the order of composted manure > commercial fertilizer > mineral fertilizer. After harvesting, soil ARGs abundance treated with mineral fertilizer, commercial fertilizer or composted manure significantly increased by 0.63, 3.19 and 8.65 times (p < 0.05), respectively, compared with the non-fertilized soil. The ARGs abundance in the pakchoi treated with composted manure was significantly higher than that of treatments with mineral fertilizer and commercial organic fertilizer. These findings indicated the application of composted pig manure would significantly increase the pollution load of ARGs in farmland soil and plant, and also promote the proliferation of farmland ARGs. Principal component analysis suggested that bacterial communities might have a significant influence on ARGs changes during the growth period of pakchoi. Network analysis further indicated ARGs changes may be mainly related to their host bacteria (including Gammaproteobacteria, Flavobacteriia and Bacilli). The results provided a proper method and useful information on reducing transmission risk of ARGs and control the propagation of ARGs in agricultural activities.202133865023
8579160.9937Microplastics and chemical leachates from plastic pipes are associated with increased virulence and antimicrobial resistance potential of drinking water microbial communities. There is increasing recognition of the potential impacts of microplastics (MPs) on human health. As drinking water is the most direct route of human exposure to MPs, there is an urgent need to elucidate MPs source and fate in drinking water distribution system (DWDS). Here, we showed polypropylene random plastic pipes exposed to different water quality (chlorination and heating) and environmental (freeze-thaw) conditions accelerated MPs generation and chemical leaching. MPs showed various morphology and aggregation states, and chemical leaches exhibited distinct profiles due to different physicochemical treatments. Based on the physiological toxicity of leachates, oxidative stress level was negatively correlated with disinfection by-products in the leachates. Microbial network analysis demonstrated exposure to leachates (under three treatments) undermined microbial community stability and increased the relative abundance and dominance of pathogenic bacteria. Leachate physical and chemical properties (i.e., MPs abundance, hydrodynamic diameter, zeta potential, total organic carbon, dissolved ECs) exerted significant (p < 0.05) effects on the functional genes related to virulence, antibiotic resistance and metabolic pathways. Notably, chlorination significantly increased correlations among pathogenic bacteria, virulence genes, and antibiotic resistance genes. Overall, this study advances the understanding of direct and indirect risks of these MPs released from plastic pipes in the DWDS.202437935064
8122170.9937Enhanced removal of antibiotic resistance genes and mobile genetic elements during sewage sludge composting covered with a semi-permeable membrane. Transmission of antibiotic resistance genes (ARGs) via air media, such as particulate matter, has been intensively investigated due to human exposure through inhalation. However, whether particulate matter originating from the atmospheric environment of composting plants can impact ARG abundance during composting is unknown. Here, we investigated the effects of the atmospheric environment of composting plants on ARG abundance during sewage sludge composting using semi-permeable membrane-covered thermophilic composting (smTC) and conventional thermophilic composting (cTC). After smTC treatment, the total abundances of ARGs and mobile genetic elements (MGEs) decreased by 42.1 % and 38.1 % compared with those of the initial phase, respectively, but they increased by 4.5- and 1.6-fold after cTC, respectively. This result suggested that smTC was more efficient at decreasing ARGs and MGEs than cTC, mainly due to a significant reduction in bacterial contamination from the atmospheric environment of composting plants that accelerated the resurgence of ARGs and MGEs. Furthermore, culture experiments demonstrated that the abundance and diversity of antibiotic-resistant bacteria during the mature phase of smTC were also significantly (P <  0.05) lower than those in the cTC treatment. Thus, covering composting with a semi-permeable membrane could decrease the risk of ARGs spreading.202032361132
7900180.9936Biochar-amended constructed wetlands enhance sulfadiazine removal and reduce resistance genes accumulation in treatment of mariculture wastewater. With the rapid development of mariculture, an increasing amount of antibiotics are being discharged into the marine environment. Effectively removing antibiotics and antibiotic resistance genes (ARGs) in mariculture wastewater with a relatively high salinity and low C/N presents challenges. Biochar-amended constructed wetlands (CWs) can effectively remove antibiotics, However, few studies have compared the impacts of biochar-amended CWs pyrolyzed at different temperatures on the treatment of mariculture wastewater. Thus, this study utilized biochar prepared at three temperatures as substrate for CWs (CW-300, CW-500, and CW-700), aiming to evaluate their efficiency to treat mariculture wastewater containing antibiotic sulfadiazine (SDZ). The results demonstrated that compared to traditional quartz sand-filled CW (NCW), the addition of biochar with a larger specific surface area significantly enhanced the removal efficiency of SDZ by 21.72%-46.96%. Additionally, the addition of biochar effectively reduced the relative abundance of one integron gene (int1) and antibiotic resistance genes (ARGs) including sul1, sul2, and sul3 in both effluent and substrates. The addition of biochar reduced the accumulation of extracellular polymeric substances within the substrate of CWs, thereby mitigating the proliferation and spread of ARGs. The microbial community structure indicated that the addition of biochar increased the abundance of the potential antibiotic-degrading bacteria such as Proteobacteria and Bacteroidota, facilitating the degradation of SDZ and mitigating the accumulation of ARGs. This study demonstrated that biochar can be a promising substrate in CWs for treating mariculture wastewater containing antibiotics.202539986428
8591190.9936Nanoscale zero-valent iron alleviate antibiotic resistance risk during managed aquifer recharge (MAR) by regulating denitrifying bacterial network. The frequent occurrence of antibiotics in reclaimed water is concerning, in the case of managed aquifer recharge (MAR), it inevitably hinders further water purification and accelerates the evolutionary resistance in indigenous bacteria. In this study, we constructed two column reactors and nanoscale zero-valent iron (nZVI) amendment was applied for its effects on water quality variation, microbial community succession, and antibiotic resistance genes (ARGs) dissemination, deciphered the underlying mechanism of resistance risk reduction. Results showed that nZVI was oxidized to iron oxides in the sediment column, and total effluent iron concentration was within permissible limits. nZVI enhanced NO(3)(-)-N removal by 15.5% through enriching denitrifying bacteria and genes, whereas made no effects on oxacillin (OXA) removal. In addition, nZVI exhibited a pivotal impact on ARGs and plasmids decreasing. Network analysis elucidated that the diversity and richness of ARG host declined with nZVI amendment. Denitrifying bacteria play a key role in suppressing horizontal gene transfer (HGT). The underlying mechanisms of inhibited HGT included the downregulated SOS response, the inhibited Type-Ⅳ secretion system and the weakened driving force. This study afforded vital insights into ARG spread control, providing a reference for future applications of nZVI in MAR.202438134694