Reduction of antibiotic resistance genes under different conditions during composting process of aerobic combined with anaerobic. - Related Documents




#
Rank
Similarity
Title + Abs.
Year
PMID
012345
754601.0000Reduction of antibiotic resistance genes under different conditions during composting process of aerobic combined with anaerobic. Single aerobic or anaerobic composting is reportedly as inefficient for removing antibiotic resistance genes (ARGs) from animal manure. This study investigates the effects of ARG removal during aerobic combined with anaerobic composting (ACA) under different conditions. The results showed that a turning frequency of once a day, the proportion of swine manure and corn straw (3:1) and an anaerobic time of 6 days were the best operating conditions for ARG reduction (>95%, especially ermF: 99.78%) during ACA. Moreover, redundancy analysis demonstrated that the bacterial community (especially Truepera, Petrimonas and Ureibacillus) had a stronger effect on ARG removal than environmental factors did (especially temperature, total phosphorus, ammonia nitrogen and pH). Network analysis indicated the important effect of these potential host bacteria on the spread of ARGs through significant co-occurrence between individual ARGs and specific bacteria. These findings offer an effective technology to reduce and block ARGs spread from animal manure.202133493747
754810.9999Maturity phase is crucial for removing antibiotic resistance genes during composting: novel insights into dissolved organic matter-microbial symbiosis system. Composting is widely regarded as an effective method for reducing antibiotic resistance genes (ARGs) in livestock and poultry manure. However, the critical mechanisms of ARGs in different composting phase are still unclear. In this study, normal composting and two types of rapid composting (without mature phase) were used to analyze the removal of ARGs and the succession of dissolved organic matter (DOM). Compared to normal composting, rapid composting reactivated tetracyclines, sulfonamide, and quinolones resistance genes during the maturation phase and reduced the total ARGs removal rates by 45.58 %-57.87 %. Humus-like components could inhibit the proliferation of ARGs, and the enrichment of protein-like components increased abundances of Pusillimonas, Persicitalea, and Pseudomonas, indirectly reducing the removal. This study is the first to demonstrate the contribution of DOM and microbial community to ARGs removal, emphasizing the importance of the maturation phase for ARGs elimination. This research provides guidance for producing safe compost products.202540311709
754720.9999Mechanism concerning the occurrence and removal of antibiotic resistance genes in composting product with ozone post-treatment. The soil application of composting product will probably cause the spread of antibiotic resistance genes (ARGs) to environment, thereby it is crucial to remove ARGs in composting product. Ozone was adopted for the first time as a post-treatment method to remove the ARGs in composting product in this study. Ozone treatment significantly removed the total ARGs and mobile genetic elements (MGEs) once ozonation process finished. After 10-day storage stage, although the amount of total intracellular ARGs and MGEs increased, the total extracellular ARGs and MGEs decreased in the ozone-treated compost product. Correlation analysis revealed that the reduction in intracellular 16S rRNA contributed to intracellular tetQ and tetW removal, while the variations of other ARGs after ozonation related to MGEs abundance. Network analysis suggested that the reduction of potential host bacteria, as well as the decline in NH(4)(+)-N and TOC after the ozonation, contributed to the intracellular ARGs removal.202133257169
809430.9998Additive quality influences the reservoir of antibiotic resistance genes during chicken manure composting. Aerobic composting is commonly used to dispose livestock manure and is an efficient way to reduce antibiotic resistance genes (ARGs). Here, the effects of different quality substrates on the fate of ARGs were assessed during manure composting. Results showed that the total relative abundances of ARGs and intI1 in additive treatments were lower than that in control, and high quality treatment with low C/N ratio and lignin significantly decreased the relative abundance of tetW, ermB, ermC, sul1 and sul2 at the end of composting. Additionally, higher quality treatment reduced the relative abundances of some pathogens such as Actinomadura and Pusillimonas, and some thermotolerant degrading-related bacteria comprising Pseudogracilibacillus and Sinibacillus on day 42, probably owing to the change of composting properties in piles. Structural equation models (SEMs) further verified that the physiochemical properties of composting were the dominant contributor to the variations in ARGs and they could also indirectly impact ARGs by influencing bacterial community and the abundance of intI1. Overall, these findings indicated that additives with high quality reduced the reservoir of antibiotic resistance genes of livestock manure compost.202134139628
809940.9998The fate of antibiotic resistance genes during co-composting of swine manure with cauliflower and corn straw. Composting is not completely effective in reducing antibiotic resistance genes (ARGs) in animal manure. This work studied the effects of different treatment conditions on the fate of ARGs in composting swine manure with cauliflower and corn straw as bulking agents. The results showed that the addition of microbial agents or the ratio of corn stalks to cauliflower (1:12) could significantly decrease the absolute abundances of most ARGs (an average of 480 times) compared with the control treatment. Principal component analysis indicated that bacterial communities were significantly correlated with ARG abundance, suggesting that microbial communities have an impact on ARG variation during co-composting. Redundancy and Network analysis confirmed the changing patterns of individual ARGs (qnrS, bla(AmpC), bla(TEM-1)) were influenced by the selectivity of host bacteria (Pseudomonas, Klebsiella, and Halocella) and environmental variables (TN, NH(3)-N, TOC, and pH). These findings helped to optimize composting conditions, thereby reducing the risk of ARGs spread.202031891854
806050.9998Responses of bacterial communities and antibiotic resistance genes to nano-cellulose addition during pig manure composting. Treatment with exogenous additives during composting can help to alleviate the accumulation of antibiotic resistance genes (ARGs) caused by the direct application of pig manure to farmland. In addition, nano-cellulose has an excellent capacity for adsorbing pollutants. Thus, the effects of adding 300, 600, and 900 mg/kg nano-cellulose to compost on the bacterial communities, mobile genetic elements (MGEs), and ARGs were determined in this study. After composting, treatment with nano-cellulose significantly reduced the relative abundance of ARGs, which was lowest in the compost product with 600 mg/kg added nano-cellulose. Nano-cellulose inhibited the rebound in ARGs from the cooling period to the maturity period, and weakened the selective pressure of heavy metals on microorganisms by passivating bio-Cu. The results also showed that MGEs explained most of the changes in the abundances of ARGs, and MGEs had direct effects on ARGs. The addition of 600 mg/kg nano-cellulose reduced the abundances of bacterial genera associated with ermQ, tetG, and other genes, and the number of links (16) between ARGs and MGEs was lowest in the treatment with 600 mg/kg added nano-cellulose. Therefore, adding 600 mg/kg nano-cellulose reduced the abundances of ARGs by affecting host bacteria and MGEs. The results obtained in this study demonstrate the positive effect of nano-cellulose on ARG pollution in poultry manure, where adding 600 mg/kg nano-cellulose was most effective at reducing the abundances of ARGs.202134649327
807660.9998Effects of chlortetracycline and copper on tetracyclines and copper resistance genes and microbial community during swine manure anaerobic digestion. As antibiotic and heavy metals are over used in the livestock industry, animal manure is a reservoir of antibiotic resistance genes (ARGs). Anaerobic digestion has been reported to have the potential to reduce ARGs. However, few studies investigated whether reduction of ARGs would be affected by different external pressures including antibiotics and heavy metals during anaerobic digestion. The purpose of this study was thus to investigate effects of both chlortetracycline (CTC) and Cu on reduction of ARGs, heavy metal resistance genes (HMRGs) and mobile genetic elements (MGEs) during the swine manure anaerobic digestion. The results showed that the predominant ARGs (tetO, tetW, tetX, tetL) could be effectively reduced (approximately 1.00 log copies/g TS) through mesophilic anaerobic digestion. Microbial community evolution was the main driver. It was interesting that Treponema might indicate the termination of anaerobic digestion and compete with ARGs host bacteria. Addition of CTC, Cu and CTC+Cu affected microbial community change and hindered removal of ARGs, especially, CTC+Cu seriously affected Treponema and ARGs during anaerobic digestion.201728432950
691570.9998Industrial-scale aerobic composting of livestock manures with the addition of biochar: Variation of bacterial community and antibiotic resistance genes caused by various composting stages. The presence of large amounts of antibiotic resistance genes (ARGs) in livestock manures poses an impending, tough safety risk to ecosystems. To investigate more comprehensively the mechanisms of ARGs removal from industrial-scale composting of livestock manure based on biochar addition, we tracked the dynamics of bacterial community and ARGs at various stages of aerobic composting of livestock manures with 10% biochar. There were no significant effects of biochar on the bacterial community and the profiles of ARGs. During aerobic composting, the relative abundance of ARGs and mobile genetic elements (MGEs) showed overall trends of decreasing and then increasing. The key factor driving the dynamics of ARGs was bacterial community composition, and the potential hosts of ARGs were Caldicoprobacter, Tepidimicrobium, Ignatzschineria, Pseudogracilibacillus, Actinomadura, Flavobacterium and Planifilum. The retention of the thermophilic bacteria and the repopulation of the initial bacteria were the dominant reasons for the increase in ARGs at maturation stage. Additionally, among the MGEs, the relative abundance of transposon gene was substantially removed, while the integron genes remained at high relative abundance. Our results highlighted that the suitability of biochar addition to industrial-scale aerobic composting needs to be further explored and that effective measures are needed to prevent the increase of ARGs content on maturation stage.202236162559
755480.9998Effects of earthworms on the fate of tetracycline and fluoroquinolone resistance genes of sewage sludge during vermicomposting. Diverse antibiotic resistance genes (ARGs) present in sewage sludge are difficult to be eliminated using conventional sludge treatment processes. To date, little remains known on the fate of the ARGs during vermicomposting of sludge. This study aimed to investigate the effect of earthworms on the fate of tetracycline and fluoroquinolone resistance genes, and integrons during vermicomposting of sewage sludge through contrasting two systems of sludge stabilization with and without earthworms. Compared to the control without earthworms, vermicomposting significantly (p < 0.05) decreased the abundances of tetracycline and fluoroquinolone resistance genes and int1, with complete removal for parC. Variations in ARGs were associated with environmental factors, horizontal gene transfer, bacterial community composition, and earthworms during vermicomposting. In addition, earthworms strongly affected the possible host bacteria encoding ARGs and Int1, abating the pathogenic bacteria in vermicomposting product. These results imply that vermicomposting could effectively reduce tetracycline and fluoroquinolone resistance genes in the sludge.201829536871
755090.9998Evaluating the effects of activated carbon on methane generation and the fate of antibiotic resistant genes and class I integrons during anaerobic digestion of solid organic wastes. The effects of activated carbon (AC) on methane production and the fate of antibiotic resistance genes (ARGs) were evaluated through comparing the anaerobic digestion performance and transformation of ARGs among anaerobic mono-digestion of food waste, co-digestion of food waste and chicken manure, and co-digestion of food waste and waste activated sludge. Results showed that adding AC in anaerobic digesters improved methane yield by at least double through the enrichment of bacteria and archaea. Conventional digestion process showed ability in removing certain types of ARGs, such as tetA, tetX, sul1, sul2, cmlA, floR, and intl1. Supplementing AC in anaerobic digester enhanced the removal of most of the ARGs in mono-digestion of food waste. The effects tended to be minimal in co-digestion of co-substrates such as chicken manure and waste activated sludge, both of which contain a certain amount of antibiotics.201829096147
7040100.9998The maturity period is the main stage of antibiotic resistance genes reduction in aerobic composting process of swine manure in sub-scale farms. This study was focused on the changes of antibiotic resistance genes (ARGs) and their potential host bacteria during the swine manure composting on sub-scale farms. Eight target ARGs increased 427% on average, with a trend of increase at early stage and decrease at later stage, and the main reduction stage appeared in maturity stage. The abundance of ARGs was mainly affected by the community succession of potential host bacteria. Composting could reduce the abundance of potential host bacteria of ARGs as well as pathogens such as Pseudomonas, and reduce the environmental risks of swine manure. N/C and S levels had a positive effect on the potential host of most ARGs. Prolonging the maturity period would inhibit the growth of potential host bacteria of ARGs during composting, therefore inhibiting the transmission of ARGs.202132971337
8091110.9998Changes in antibiotic resistance genes and mobile genetic elements during cattle manure composting after inoculation with Bacillus subtilis. This study explored the effects of Bacillus subtilis at four levels (0, 0.5%, 1%, and 2% w/w compost) on the variations in ARGs, mobile genetic elements (MGEs), and the bacterial community during composting. The composting process had a greater impact on ARGs than Bacillus subtilis. The main ARG detected was sul1. The addition of Bacillus subtilis at 0.5% reduced the relative abundances of ARGs, MGEs, and human pathogenic bacteria (by 2-3 logs) in the mature products. Network and redundancy analyses suggested that intI1, Firmicutes, and pH were mainly responsible for the changes in ARGs, thus controlling these factors might help to inhibit the spread of ARGs.201931442833
7551120.9998Microbial community evolution and fate of antibiotic resistance genes during sludge treatment in two full-scale anaerobic digestion plants with thermal hydrolysis pretreatment. Anaerobic digestion (AD) with thermal hydrolysis pretreatment is widely used as an efficient sludge treatment nowadays. However, the evolution of microbial community (especially for the archaea community), the fate of antibiotic resistance genes (ARGs), and their associations during such process in full-scale sludge treatment plants are rarely reported. Therefore, these scientific questions were explored at two full-scale sludge treatment plants through high-throughput sequencing and quantitative PCR. Results showed that Methanobacterium and Methanosphaera were the dominant archaea in thermal hydrolyzed sludge. The predominant bacteria in the sludge first shifted from nutrients removal functional bacteria to spore-forming bacteria after thermal hydrolysis, and then shifted to fermentative bacteria after AD. The full-scale plants could select ermB, ermF, mefA/E, qnrS and tetM. Though the bacteria and archaea biomass and community largely influenced the fate of ARGs, multiple linear regression analysis showed that the total ARGs were mainly affected by mobile genetic elements (MGEs).201931158777
7039130.9998Profiles and key drivers of bacteria/phage co-mediated antibiotic resistance genes during swine manure composting amended with humic acid. Phages can promote the spread of antibiotic resistance genes (ARGs) in agricultural environments through transduction. However, studies on phage-mediated ARG profiles during composting have not been performed. This study investigated the effects of adding humic acid (HA) on the abundances of bacteria/phage co-mediated ARGs (b/pARGs) during swine manure composting and the key factors that affected the transmission of b/pARGs. The results showed that the addition of 5 % HA during composting could effectively reduce the absolute abundances of b/pARGs, inhibit the proliferation of pathogenic microorganisms (e.g., Corynebacterium and Streptococcus) that carried ARGs, and ultimately affect the fate of b/pARGs in the composting process by regulating key environmental factors to change the abundance of co-host bacteria. Overall, the findings of this study provided new information for understanding the main driving factors affecting the b/pARGs profile and provided a reference for the prevention and control of ARGs pollution during composting.202336774987
6917140.9998Response characteristics of antibiotic resistance genes and bacterial communities during agricultural waste composting: Focusing on biogas residue combined with biochar amendments. This research investigated biogas residue and biochar addition on antibiotic resistance genes (ARGs), mobile genetic elements (MGEs), and changes in bacterial community during agricultural waste composting. Sequencing technique investigated bacterial community structure and ARGs, MGEs changes. Correlations among physicochemical factors, ARGs, MGEs, and bacterial community structure were determined using redundancy analysis. Results confirmed that biochar and biogas residue amendments effectively lowered the contents of ARGs and MGEs. The main ARGs detected was sul1. Proteobacteria and Firmicutes were the main host bacteria strongly associated with the dissemination of ARGs. The dynamic characteristics of the bacterial community were strongly correlated with pile temperature and pH (P < 0.05). Redundancy and network analysis revealed that nitrate, intI1, and Firmicutes mainly affected the in ARGs changes. Therefore, regulating these key variables would effectively suppress the ARGs spread and risk of compost use.202336657587
6919150.9998Enhanced removal of antibiotic resistance genes during chicken manure composting after combined inoculation of Bacillus subtilis with biochar. This study explored the combined effects of Bacillus subtilis inoculation with biochar on the evolution of bacterial communities, antibiotic resistance genes (ARGs), and mobile genetic elements (MGEs) during the composting of chicken manure. The results showed that B. subtilis inoculation combined with biochar increased bacterial abundance and diversity as well as prolonged the compost thermophilic period. Promoted organic matter biodegradation and facilitated the organic waste compost humification process, reduced the proliferation of ARGs by altering the bacterial composition. Firmicutes and Actinobacteriota were the main resistant bacteria related to ARGs and MGEs. The decrease in ARGs and MGEs was associated with the reduction in the abundance of related host bacteria. Compost inoculation with B. subtilis and the addition of biochar could promote nutrient transformation, reduce the increase in ARGs and MGEs, and increase the abundance of beneficial soil taxa.202437778803
8062160.9998Nanoscale 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
7544170.9998Antibiotic resistance reduction mechanisms during thermophilic anaerobic digestion of microalgae-bacteria aggregates. Microalgae-bacteria-based systems are an emerging and promising approach for wastewater treatment plants (WWTP), having nutrient and antibiotic resistance removal comparable to conventional technologies. Still, antibiotic-resistance genes and bacteria (ARG and ARB) can proliferate in microalga-bacteria aggregates (MABA), a concern to control. Different temperature regimes of MABA continuous anaerobic digestion (AD), thermophilic (55 °C), and mesophilic (35 °C) were evaluated in this study as a strategy to eliminate ARB and ARGs. Plate counting techniques and metagenomic-based analysis revealed that thermophilic temperature had a better performance, achieving ARB log reductions of 1.1 to 1.7 for various antibiotics and significantly reduced ARG abundance up to 19.5 ± 0.8 ppm. The microbiome selection, the mobilome restriction, and directed functionality to thermal stress resistance were the main mechanisms responsible for resistome reduction at thermophilic conditions. Thermophilic AD effectively manages antibiotic resistance in microalgae-bacteria aggregates, which has important implications for wastewater treatment and reduces environmental risks.202539756663
6950180.9998Ceftiofur in swine manure contributes to reducing pathogens and antibiotic resistance genes during composting. Aerobic composting is a common way for the disposal of feces produced in animal husbandry, and can reduce the release of antibiotic resistance genes (ARGs) from feces into the environment. In this study, we collected samples from two distinct treatments of swine manure compost with and without ceftiofur (CEF), and identified the ARGs, mobile genetic elements (MGEs), and bacterial community by metagenomic sequencing. The impacts of CEF on the bacterial community composition and fate of ARGs and MGEs were investigated. With increasing composting temperature and pH, the concentration of CEF in the manure decreased rapidly, with a degradation half-life of 1.12 d and a 100% removal rate after 10 d of aerobic composting. Metagenomics demonstrated that CEF in the manure might inhibit the growth of Firmicutes and Proteobacteria, thereby reducing some ARGs and MGEs hosted by these two bacteria, which was further confirmed by the variations of ARGs and MGEs. A further redundancy analysis suggested that pH and temperature are key environmental factors affecting ARG removal during composting, and intI1 and bacterial communities also have significant influence on ARG abundance. These results are of great significance for promoting the removal of some ARGs from animal manure by controlling some key environmental factors and the type of antibiotics used in animals.202438685300
7552190.9998Effect of temperature on removal of antibiotic resistance genes by anaerobic digestion of activated sludge revealed by metagenomic approach. As antibiotic resistance continues to spread globally, there is growing interest in the potential to limit the spread of antibiotic resistance genes (ARGs) from wastewater sources. In particular, operational conditions during sludge digestion may serve to discourage selection of resistant bacteria, reduce horizontal transfer of ARGs, and aid in hydrolysis of DNA. This study applied metagenomic analysis to examine the removal efficiency of ARGs through thermophilic and mesophilic anaerobic digestion using bench-scale reactors. Although the relative abundance of various ARGs shifted from influent to effluent sludge, there was no measureable change in the abundance of total ARGs or their diversity in either the thermophilic or mesophilic treatment. Among the 35 major ARG subtypes detected in feed sludge, substantial reductions (removal efficiency >90%) of 8 and 13 ARGs were achieved by thermophilic and mesophilic digestion, respectively. However, resistance genes of aadA, macB, and sul1 were enriched during the thermophilic anaerobic digestion, while resistance genes of erythromycin esterase type I, sul1, and tetM were enriched during the mesophilic anaerobic digestion. Efflux pump remained to be the major antibiotic resistance mechanism in sludge samples, but the portion of ARGs encoding resistance via target modification increased in the anaerobically digested sludge relative to the feed. Metagenomic analysis provided insight into the potential for anaerobic digestion to mitigate a broad array of ARGs.201525994259