Shifting interactions among bacteria, fungi and archaea enhance removal of antibiotics and antibiotic resistance genes in the soil bioelectrochemical remediation. - Related Documents




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757901.0000Shifting interactions among bacteria, fungi and archaea enhance removal of antibiotics and antibiotic resistance genes in the soil bioelectrochemical remediation. BACKGROUND: Antibiotics and antibiotic resistance genes (ARGs) are two pollutants in soil, especially ARGs as one of the top three threats to human health. The performance of soil microbial fuel cells (MFCs) fuelled with antibiotics was investigated. RESULTS: In this study, soil MFCs spiked with tetracycline exhibited optimal bioelectricity generation, which was 25% and 733% higher than those of MFCs spiked with sulfadiazine and control, respectively. Compared with the non-electrode treatment, not only did functional micro-organisms change in open- and closed-circuit treatments, but also the microbial affinities, respectively, increased by 50% and 340% to adapt to higher removal of antibiotics. For the open-circuit treatment, the ineffective interspecific relation of micro-organisms was reduced to assist the removal efficiency of antibiotics by 7-27%. For the closed-circuit treatment, an intensive metabolic network capable of bioelectricity generation, degradation and nitrogen transformation was established, which led to 10-35% higher removal of antibiotics. Importantly, the abundances of ARGs and mobile genetic element (MGE) genes decreased after the introduction of electrodes; especially in the closed-circuit treatment, the highest reduction of 47% and 53% was observed, respectively. CONCLUSIONS: Soil MFCs possess advantages for the elimination of antibiotics and ARGs with sevenfold to eightfold higher electricity generation than that of the control treatment. Compared with sulphonamides, the enhancement removal of tetracycline is higher, while both potential ARG propagation risk is reduced in soil MFCs. This study firstly synchronously reveals the relationships among bacteria, fungi and archaea and with ARGs and MGE genes in soil bioelectrochemical systems.201931249623
756010.9998The effect of bacterial functional characteristics on the spread of antibiotic resistance genes in Expanded Granular Sludge Bed reactor treating the antibiotic wastewater. To explore the fate and spreading mechanism of antibiotics resistance genes (ARGs) in antibiotics wastewater system, a laboratory-scale (1.47 L) Expanded Granular Sludge Bed (EGSB) bioreactor was implemented. The operating parameters temperature (T) and hydraulic retention time (HRT) were mainly considered. This result showed the removal of ARGs and COD was asynchronous, and the recovery speed of ARGs removal was slower than that COD removal. The decreasing T was attributed to the high growth rate of ARGs host bacteria, while the shortened HRT could promote the horizontal and vertical gene transfer of ARGs in the sludge. The analysis result of potential bacterial host showed more than half of the potential host bacteria carried 2 or more ARGs and suggested an indirect mechanism of co-selection of multiple ARGs. Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt) was used to investigate the functional characteristics of bacterial community. This result showed the bacterial functional genes contributed 40.41% to the abundance change of ARGs in the sludge, which was higher that of bacterial community. And the function genes of "aromatic hydrocarbon degradation", "Replication, recombination and repair proteins" and "Flagellar assembly" were mainly correlated with the transfer of ARGs in the sludge. This study further revealed the mechanism of ARGs spread in the EGSB system, which would provide new ideas for the development of ARGs reduction technology.202134488144
756420.9998Formation, characteristics and microbial community of aerobic granular sludge in the presence of sulfadiazine at environmentally relevant concentrations. The growing occurrence of antibiotics in water environment is causing increasing concern. To investigate the impact of frequently detected sulfadiazine on the formation of aerobic granular sludge, four sequencing batch reactors (SBRs) were set up with different environmentally relevant concentrations of sulfadiazine. Results showed that sulfadiazine pressure could lead to larger and more compact sludge particles and cause slight effect on reactor performance. Presence of sulfadiazine apparently increased the extracellular polymeric substances (EPS) secretion of microorganisms. Quantitative polymerase chain reaction (qPCR) showed that the abundances of sulfanilamide resistance genes in sludge increased with addition of sulfadiazine significantly. Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt) was used to predict functional genes, results showed that sulfadiazine led to an increase of specific functional genes. Thereby, it concluded that microorganisms could change the community structure by acclimating of functional bacteria and antibiotic resistance species to adapt to the antibiotic stress.201829197771
808230.9997Deciphering the toxic effects of antibiotics on denitrification: Process performance, microbial community and antibiotic resistance genes. The extensive application of antibiotics, and the occurrence and spread of antibiotic resistance genes (ARGs) shade health risks to human and animal. The long-term effects of sulfamethoxazole (SMX) and tetracycline (TC) on denitrification process were evaluated in this study, with the focus on nitrogen removal performance, microbial community and ARGs. Results showed that low-concentration SMX and TC (<0.2 mg L(-1)) initially caused a deterioration in nitrogen removal performance, while higher concentrations (0.4-20 mg L(-1)) of both antibiotics had no further inhibitory influences. The abundances of ARGs in both systems generally increased during the whole period, and most of them had significant correlations with intI1, especially efflux-pump genes. Castellaniella, which was the dominant genus under antibiotic pressure, might be potential resistant bacteria. These findings provide an insight into the toxic effects of different antibiotics on denitrification process, and guides future efforts to control antibiotics pollution in ecosystems.202032250829
808640.9997Biofilm enhanced the mitigations of antibiotics and resistome in sulfadiazine and trimethoprim co-contaminated soils. Reducing antibiotic levels in soil ecosystems is vital to curb the dissemination of antimicrobial resistance genes (ARGs) and mitigate global health threats. However, gaps persist in understanding how antibiotic resistome can be suppressed during antibiotic degradation. Herein, we investigate the efficacy of a biochar biofilm incorporating antibiotics-degrading bacterial strain (Arthrobacter sp. D2) to mitigate antibiotic resistome in non-manured and manure-amended soils with sulfadiazine (SDZ) and trimethoprim (TMP) contamination. Results show that biofilm enhanced SDZ degradation by 83.0% within three days and increased TMP attenuation by 55.4% over 60 days in non-manured soils. In the non-manured black soil, the relative abundance of ARGs increased initially after biofilm inoculation. However, by day 30, it decreased by 20.5% compared to the controls. Moreover, after 7 days, biofilm reduced TMP by 38.5% in manured soils and decreased the total ARG abundance by 19.0%. Thus, while SDZ degradation did not increase sulfonamide resistance genes, TMP dissipation led to a proliferation of insertion sequences and related TMP resistance genes. This study underscores the importance of antibiotic degradation in reducing related ARGs while cautioning against the potential proliferation and various ARGs transfer by resistant microorganisms.202439255667
796650.9997How heavy metal stress promotes dissemination of antibiotic resistance genes in the activated sludge process. Heavy metals have been recently revealed as promoters to antibiotic resistance gene (ARG) dissemination in water environment, but their influence on ARG transfer in the activated sludge process has not been clear. In this study, a set of sequencing batch reactors (SBRs) and micro-scale microfluidic chips were established to quantify the impacts of heavy metals (0.5 mM of Pb, 0.1 mM of As, and 0.005 mM of Hg) on the ARG spreading in the activated sludge consortium. Under heavy metal stress, transfer frequencies were 1.7-3.6 folds increase compared to the control. Gram-negative bacteria increased significantly after heavy metal added, which were more prone to receiving resistant plasmid from donors. Meanwhile, the relative expression of genes related to conjugation changed in activated sludge, especially the expression of outer membrane protein and oxidative stress regulatory genes increased by 2.9-7.4 folds and 7.8-13.1 folds, respectively. Furthermore, using microfluidic chips, the dynamics of ARG transfer was observed at single cell level under heavy metal pressure. Heavy metals firstly promoted conjugation and then vertical gene transfer played an important part for ARG spreading. The results provided in-depth understanding of the influence of heavy metals on ARG behavior in the environment.202235724617
758460.9997Responses of microbial community and antibiotic resistance genes to co-existence of chloramphenicol and salinity. In recent years, the risk from environmental pollution caused by chloramphenicol (CAP) has emerged as a serious concern worldwide, especially for the co-selection of antibiotic resistance microorganisms simultaneously exposed to CAP and salts. In this study, the multistage contact oxidation reactor (MCOR) was employed for the first time to treat the CAP wastewater under the co-existence of CAP (10-80 mg/L) and salinity (0-30 g/L NaCl). The CAP removal efficiency reached 91.7% under the co-existence of 30 mg/L CAP and 10 g/L NaCl in the influent, but it fluctuated around 60% with the increase of CAP concentration and salinity. Trichococcus and Lactococcus were the major contributors to the CAP and salinity shock loads. Furthermore, the elevated CAP and salinity selection pressures inhibited the spread of CAP efflux pump genes, including cmlA, tetC, and floR, and significantly affected the composition and abundance of antibiotic resistance genes (ARGs). As the potential hosts of CAP resistance genes, Acinetobacter, Enterococcus, and unclassified_d_Bacteria developed resistance against high osmotic pressure and antibiotic environment using the efflux pump mechanism. The results also revealed that shifting of potential host bacteria significantly contributed to the change in ARGs. Overall, the co-existence of CAP and salinity promoted the enrichment of core genera Trichococcus and Lactococcus; however, they inhibited the proliferation of ARGs. KEY POINTS: • Trichococcus and Lactococcus were the core bacteria related to CAP biodegradation • Co-existence of CAP and salinity inhibited proliferation of cmlA, tetC, and floR • The microorganism resisted the CAP using the efflux pump mechanism.202236205764
703470.9997Meta-analysis reveals the processes and conditions of using biochar to control antibiotic resistance genes in soil. Soil is a significant reservoir of antibiotic resistance genes (ARGs) and an important habitat for pathogens associated with many clinical infections and plant disease outbreaks. Although scientists have found that biochar can reduce ARGs in soil, the understanding of how biochar removes soil ARGs and the influencing factors remains limited. Here, a meta-analysis of 65 published studies was conducted to illuminate the mechanisms through which biochar remediates ARG-contaminated soils. In biochar-amended soil, the antibiotic content significantly decreased by 24.1 %, while the abundances of mobile genetic elements and ARG host bacteria declined by 23.5 % and 12.1 %, respectively. The reduced antibiotic content, suppressed mobile genetic elements, and altered bacterial community structure collectively led to a 41.8 % reduction in soil ARG abundance. In addition, wood-derived biochar pyrolyzed at 300-500 °C exhibited a substantial advantage in the remediation of ARGs. Furthermore, biochar application decreased the abundance of ARGs in alkaline and neutral soil more markedly than that in acidic soil. The results of this research confirmed the positive mitigating effect of biochar on ARGs in soil, providing valuable insights for the prevention and control of ARG pollution.202540359860
758380.9997Insights into the combined effect of ofloxacin and humic substances on sewage sludge anaerobic digestion. Humic substances (HS) and antibiotics are present simultaneously in various environments. However, the influence path and consequences of HS on antibiotics behaviors in complex anaerobic microbial systems are rarely known, hindering the understanding and control of antibiotics risks. This study for the first time investigated the combined effects of ofloxacin (OFL) and HS in sewage sludge anaerobic digestion system. Experimental results showed that OFL alone reduced the cumulative methane production and the maximum methane production rate by 14.6 % and 33.5 %, respectively. The methane production curves showed step by step adaption, which might be related with the increase of antibiotics resistance genes and their potential hosts. The coexistence of low concentration (6 % of sludge volatile solid) HS could alleviate the inhibition of OFL on hydrolysis-related bacteria and genes to a certain extent, thereby enhanced the methane production by 4.8 %. However, the coexistence of high concentration (12-24 % of sludge volatile solid) HS intensified the inhibition on hydrolysis-related bacteria and genes, and had more potential to combine with organic matters to prevent sludge solubilization, macromolecular organics hydrolysis and OFL degradation, thereby further decreasing the methane production by 7.6-15.9 %. Besides, the coexistence of OFL and high concentration HS increased the antimicrobial resistance and pathogenicity risks of digested sludge, by enhancing the residual level of verified pathogens, antibiotics resistance genes and virulence factor genes. This study provides new insights into the environmental risks of combined antibiotics and HS pollution, and offers a basis for strengthening the safe treatment and disposal of sewage sludge.202540752562
851690.9997Graphene Oxide Inhibits Antibiotic Uptake and Antibiotic Resistance Gene Propagation. Antibiotics and antibiotic resistance genes (ARGs) in the natural environment have become substantial threats to the ecosystem and public health. Effective strategies to control antibiotics and ARG contaminations are emergent. A novel carbon nanomaterial, graphene oxide (GO), has attracted a substantial amount of attention in environmental fields. This study discovered the inhibition effects of GO on sulfamethoxazole (SMZ) uptake for bacteria and ARG transfer among microorganisms. GO promoted the penetration of SMZ from intracellular to extracellular environments by increasing the cell membrane permeability. In addition, the formation of a GO-SMZ complex reduced the uptake of SMZ in bacteria. Moreover, GO decreased the abundance of the sulI and intI genes by approximately 2-3 orders of magnitude, but the global bacterial activity was not obviously inhibited. A class I integron transfer experiment showed that the transfer frequency was up to 55-fold higher in the control than that of the GO-treated groups. Genetic methylation levels were not significant while sulI gene replication was inhibited. The biological properties of ARGs were altered due to the GO-ARG noncovalent combination, which was confirmed using multiple spectral analyses. This work suggests that GO can potentially be applied for controlling ARG contamination via inhibiting antibiotic uptake and ARG propagation.201627934199
7630100.9997Coexistence of silver ion and tetracycline at environmentally relevant concentrations greatly enhanced antibiotic resistance gene development in activated sludge bioreactor. Antibiotic resistance has become a global public health problem. Recently, various environmental pollutants have been reported to induce the proliferation of antibiotic resistance. However, the impact of multiple pollutants (e.g., heavy metals and antibiotics), which more frequently occur in practical environments, is poorly understood. Herein, one widely distributed heavy metal (Ag(+)) and one frequently detected antibiotic (tetracycline) were chosen to investigate their coexisting effect on the proliferation of antibiotic resistance in the activated sludge system. Results show that the co-occurrence of Ag(+) and tetracycline at environmentally relevant concentrations exhibited no distinct inhibition in reactor performances. However, they inhibited the respiratory activity by 42%, destroyed the membrane structure by 218%, and increased membrane permeability by 29% compared with the blank control bioreactor. Moreover, the relative abundances of target antibiotic resistance genes (ARGs) (e.g., tetA, bla(TEM-1), and sulII) in effluent after exposure of coexisting Ag(+) and tetracycline were increased by 92-1983% compared with those in control reactor, which were 1.1-4.3 folds higher than the sum of the sole ones. These were possibly attributed to the enrichments of antibiotic-resistant bacteria. The results would illumine the coexisting effect of heavy metals and antibiotics on the dissemination of ARGs in activated sludge system.202234482077
7598110.9997Aspartame affects methane yield and enhances transmission of antibiotic resistance genes during anaerobic digestion of sludge. Aspartame (ASP) is a widely used artificial sweetener, yet recent studies have shown that ASP have potential toxic effect. ASP is also detected in sludge, however, the influence of ASP on the performance of sludge anaerobic digestion and the fate of antibiotic resistance genes (ARGs) have not been thoroughly investigated. Under stress of 0, 0.5, 5 and 50 mg/L ASP, cumulative methane production was 181.7, 167.0, 154.0 and 140.8 mlCH(4)/g VSS, respectively. ASP inhibited the dissolution and conversion of organic matter in sludge. Sequencing data revealed a decline in the abundance of functional microorganisms compared to control, such as hydrolytic-acidifying bacteria and methanogens, potentially attributed to increased intracellular reactive oxygen species and damaged cell membranes caused by ASP addition. Specifically, 50 mg/L ASP reduced the total abundance of methanogens by 59.40 % compared to control. Concurrently, alterations in microbial communities along with an increase in Tn916 and intI1 were observed, increasing the abundance of ARGs. The total abundance of five ARGs peaked at 1.43E+ 12 copies/g at 5 mg/L ASP, representing 139 % of the control. This research contributes valuable insights into the alterations in anaerobic digestion caused by ASP, emphasizing the potential risks in the overall environmental system.202539616849
7581120.9997Enhanced performance of anaerobic digestion of cephalosporin C fermentation residues by gamma irradiation-induced pretreatment. Antibiotic fermentation residues is a hazardous waste due to the existence of residual antibiotics and antibiotic resistance genes (ARGs), probably leading to the induction and spread of antibiotic resistant bacteria (ARB) in the environment, which could pose potential harm to the ecosystem and human health. It is urgent to develop an effective technology to remove the residual antibiotics and ARGs. In this study, the anaerobic digestion combined with gamma irradiation was applied for the disposal and utilization of cephalosporin C fermentation residues. The experimental results showed that the antibacterial activities of cephalosporin C against Staphylococcus aureus were significantly decreased after anaerobic digestion. The removal of tolC, a multidrug resistant gene, was improved up to 100% by the combination of gamma irradiation and anaerobic digestion compared to solely anaerobic digestion process, which may be due to the changes of microbial community structures induced by gamma irradiation.202031590081
7585130.9997Impacts of engineered nanoparticles and antibiotics on denitrification: Element cycling functional genes and antibiotic resistance genes. The wide presence of antibiotics and minerals warrants their combined effects on the denitrification in natural aquatic environment. Herein, we investigated the effects of two antibiotics, sulfamethazine (SMZ) and chlortetracycline (CTC), on the reduction of NO(3)(-)-N and accumulation of NO(2)(-)-N in the absence and presence of engineered nanoparticles (NPs) (Al(2)O(3), SiO(2), and geothite) using 16 S rRNA sequencing and high-throughput quantitative PCR. The results showed that the addition of antibiotics inhibited the reduction of NO(3)(-)-N by changing the bacterial community structure and reducing the abundance of denitrification genes, while engineered NPs promoted the denitrification by increasing the abundance of denitrification genes. In the binary systems, engineered NPs alleviated the inhibitory effect of antibiotics through enriching the denitrification genes and adsorbing antibiotics. Antibiotics and its combination with engineered NPs changed the composition of functional genes related to C, N, P, S metabolisms (p < 0.01). The addition of antibiotics and/or engineered NPs altered the bacterial community structure, which is dominated by the genera of Enterobacter (40.7-90.5%), Bacillus (4.9-58.5%), and Pseudomonas (0.21-12.7%). The significant relationship between denitrification, carbon metabolism genes, and antibiotic resistance genes revealed that the heterotrophic denitrifying bacteria may host the antibiotic resistance genes and denitrification genes simultaneously. The findings underscore the significance of engineered NPs in the toxicity assessment of pollutants, and provide a more realistic insight into the toxicity of antibiotics in the natural aquatic environment.202235738104
7030140.9997Metagenomic profiling of antibiotic resistance genes/bacteria removal in urban water: Algal-bacterial consortium treatment system. Antibiotic resistance genes (ARGs) have exhibited significant ecological concerns, especially in the urban water that are closely associated with human health. In this study, with presence of exogenous Chlorella vulgaris-Bacillus licheniformis consortium, most of the typical ARGs and MGEs were removed. Furthermore, the relative abundance of potential ARGs hosts has generally decreased by 1-4 orders of magnitude, revealing the role of algal-bacterial consortium in cutting the spread of ARGs in urban water. While some of ARGs such as macB increased, which may be due to the negative impact of algicidal bacteria and algal viruses in urban water on exogenous C. vulgaris and the suppression of exogenous B. licheniformis by indigenous microorganisms. A new algal-bacterial interaction might form between C. vulgaris and indigenous microorganisms. The interplay between C. vulgaris and bacteria has a significant impact on the fate of ARGs removal in urban water.202438801952
7561150.9997Deciphering antibiotic resistome variations during nitrogen removal process transition under mixed antibiotics stress: Assembly process and driving factors. Antibiotic resistome, which encompasses all types of antibiotic resistance genes (ARGs) in a given environment, has received increasing attention in research on different wastewater treatment processes. However, the variation in antibiotic resistome during the transition from the full nitrification-denitrification to the shortcut nitrification-denitrification process remains unclear. In this study, a total of 269 targeted gene subtypes were identified, along with 108 genes were consistently present in all samples. The introduction of mixed antibioticsrapidly increased the abundance of corresponding and non-corresponding ARGs, as well as that of mobile genetic elements.The variations in of the antibiotic resistome were primarily driven by dissolved oxygen and nitrite accumulation rate. Moreover, 34 bacterial genera were identified as potential ARG hosts, with most denitrifiers considered as potential antibiotic-resistant bacteria, including Branchymonas, Rhodobacter, and Thauera. This study provides a method for controlling antibiotic resistance by regulating the changes in environmental variables and bacterial communities.202339492537
7957160.9997Differential size-dependent response patterns and antibiotic resistance development mechanism in anammox consortia. Antibiotic resistance is a global threat to human and animal health. Anaerobic ammonia oxidation (anammox) is an efficient and innovative wastewater treatment technology, which can be served as a promising approach to teat antibiotic wastewater. This study systematically investigated effects of sulfamethazine on the performance, microbial community dynamics and the resistome in anammox systems inoculated with different-sized granular sludge. The activity and performance of small (< 0.5 mm) anammox granules were more susceptible to sulfamethazine stress than those of medium (0.5-1.0 mm) and large (1.0-2.0 mm) granules. Sulfamethazine addition greatly increased the diversity and abundance of mobile genetic elements (MGEs) and antibiotic resistance genes (ARGs). Based on the metagenomic analysis, the horizontal transfer of ARGs in the anammox system was upregulated through bacterial oxidative stress, pili synthesis and type IV secretion system. In addition, two strains of sulfamethazine-resistant bacteria (Pseudomonas asiatica sp. nov. and Pseudomonas shirazica sp. nov.) were isolated from the anammox system. Their whole genome sequencing results showed that the most abundant plasmid was pkF7158B, which mediated the horizontal transfer of two main multidrug resistance genes (cpxR and mexB). This work provides a holistic insight into microbial heterogeneity of different-sized anammox granular sludge and their evolution and resistance development mechanism.202540086246
7029170.9997Filamentous bacteria-induced sludge bulking can alter antibiotic resistance gene profiles and increase potential risks in wastewater treatment systems. Sludge bulking caused by filamentous bacteria is a prevalent issue in wastewater treatment systems. While previous studies have primarily concentrated on controlling sludge bulking, the biological risks associated with it have been overlooked. This study demonstrates that excessive growth of filamentous bacteria during sludge bulking can significantly increase the abundance of antibiotic resistance genes (ARGs) in activated sludge. Through metagenomic analysis, we identified specific ARGs carried by filamentous bacteria, such as Sphaerotilus and Thiothrix, which are responsible for bulking. Additionally, by examining over 1,000 filamentous bacterial genomes, we discovered a diverse array of ARGs across different filamentous bacteria derived from wastewater treatment systems. Our findings indicate that 74.84% of the filamentous bacteria harbor at least one ARG, with the occurrence frequency of ARGs in these bacteria being approximately 1.5 times higher than that in the overall bacterial population in activated sludge. Furthermore, genomic and metagenomic analyses have shown that the ARGs in filamentous bacteria are closely linked to mobile genetic elements and are frequently found in potentially pathogenic bacteria, highlighting potential risks posed by these filamentous bacteria. These insights enhance our understanding of ARGs in activated sludge and underscore the importance of risk management in wastewater treatment systems.202439094405
7022180.9997Fate of antibiotics, antibiotic-resistant bacteria, and cell-free antibiotic-resistant genes in full-scale membrane bioreactor wastewater treatment plants. The removal of antibiotics, antibiotic-resistant bacteria (ARB), and cell-free antibiotic-resistant genes (ARGs) and the microbial community of ARB were investigated in detail to understand their fate and provide valuable information on the feasibility of full-scale membrane bioreactor (MBR). The potential risks of cell-free ARGs to the receiving environment were discovered. High influent antibiotic concentration could inhibit the microbial activity of MBR sludge, whereas good antibiotic removal could be maintained because of relatively long solid retention time and high biomass retention. Approximately 61.8%-77.5% of the total antibiotics were degraded, and 22.5%-38.2% of the total antibiotics were adsorbed by MBR sludge on average. The individual antibiotic removal presented intense discrepancy because of the chemical construction and distribution coefficient of antibiotics. Aeromonas exhibited specific antibiotic resistance to ampicillin and erythromycin, Escherichia became the predominant genera in kanamycin-ARB and tetracycline-ARB, and Klebsiella and Bacteroides were the particular genera that exhibited distinct antibiotic resistance to ciprofloxacin. A significant correlation was found between cell-free ARG abundance and ARB content, and relatively high effluent cell-free ARG abundance facilitated the proliferation and transmission of ARB. The impacts of the receiving environment to eliminate the ecological risks and severe threats to human health should be investigated because of the low decay ratio and long-term persistence of cell-free ARGs.202031986335
8588190.9997Does lipid stress affect performance, fate of antibiotic resistance genes and microbial dynamics during anaerobic digestion of food waste? The dissemination of antibiotic resistance genes (ARGs) in food waste (FW) disposal can pose severe threats to public health. Lipid is a primary composition in FW, while whether lipid stress can affect ARGs dynamics during anaerobic digestion (AD) process of FW is uncertain. This study focused on the impacts of lipid stress on methane production, fate of ARGs and its microbial mechanisms during AD of FW. Results showed that high lipid content increased methane yield but prolonged hydrolysis and lag time of methane production compared to AD of FW without oil. Moreover, variations of ARGs were more susceptible to lipid stress. Lipid stress could facilitate the reduction of total ARGs abundances compared to the group without oil, particularly restraining the proliferation of sul1, aadA1 and mefA in AD systems (P < 0.05). Mantel test suggested that integrons (intl1 and intl2) were significantly correlated with all detected ARGs (r: 0.33, P < 0.05), indicating that horizontal gene transfer mediated by integrons could be the driving force on ARGs dissemination. Network analysis suggested that Firmicutes, Bacteroidetes, Synergistetes and Proteobacteria were the main potential hosts of ARGs. In addition, under the lipid stress, the reduction of host bacteria was responsible for the elimination of several specific ARGs, thereby affecting ARGs profiles. These findings firstly deciphered ARGs dynamics and their driving factors responding to lipid stress during anaerobic biological treatment of FW.202133250254