Unraveling the effect of micro/nanoplastics on the occurrence and horizontal transfer of environmental antibiotic resistance genes: Advances, mechanisms and future prospects.

Microplastics can not only serve as vectors of antibiotic resistance genes (ARGs), but also they and even nanoplastics potentially affect the occurrence of ARGs in indigenous environmental microorganisms, which have aroused great concern for the development of antibiotic resistance. This article specifically reviews the effects of micro/nanoplastics (concentration, size, exposure time, chemical additives) and their interactions with other pollutants on environmental ARGs dissemination. The changes of horizontal genes transfer (HGT, i.

Diverse bacterial hosts and potential risk of antibiotic resistomes in ship ballast water revealed by metagenomic binning.

Ship ballast water promoting the long-range migration of antibiotic resistance genes (ARGs) has raised a great concern. This study attempted to reveal ARGs profile in ballast water and decipher their hosts and potential risk using metagenomic approaches. In total, 710 subtypes across 26 ARG types were identified among the ballast water samples from 13 ships of 11 countries and regions, and multidrug resistance genes were the most dominant ARGs.

Responses of compositions, functions, and assembly processes of bacterial and microeukaryotic communities to long-range voyages in simulated ballast water.

Ballast water is one of the main vectors for the spread of harmful organisms among geologically isolated waters. However, the successional processes of microbial functions and assembly processes in ballast water during the long-term shipping voyage remain unclear. In this study, the compositions, ecological functions, community assembly, and potential environmental drivers of bacteria and microeukaryotes were investigated in simulated ballast water microcosms for 120 days.

Insight into the responses of antibiotic resistance genes in microplastic biofilms to zinc oxide nanoparticles and zinc ions pressures in landfill leachate.

Microplastic (MP) biofilms are hotspots of antibiotic resistance genes (ARGs) in landfill environment. MP biofilms in landfill leachate coexist with heavy metals and metallic nanoparticles (NPs) that considered to be the selective agents of ARGs. However, the effects of these selective pressures on ARGs in MP biofilms and their differences in MP-surrounding leachate have not been well understood.

The prevalence of potential pathogens in ballast water and sediments of oceangoing vessels and implications for management.

Ballast water and sediments can serve as prominent vectors for the widespread dispersal of pathogens between geographically distant areas. However, information regarding the diversity and distribution of the bacterial pathogens in ballast water and sediments is highly limited. In this study, using high-throughput sequencing and quantitative PCR, we investigated the composition and abundance of potential pathogens, and their associations with indicator microorganisms.

Deciphering the characterization, ecological function and assembly processes of bacterial communities in ship ballast water and sediments.

Various microorganisms are transported worldwide via the water and sediments inside ship ballast tanks. Nevertheless, the ecological functions and assembly processes of bacterial communities in ballast water and sediments remain poorly understood. Here, we investigated the bacterial composition, community assembly processes, and putative functions through analyses of 70 ballast water and sediment samples obtained from various ships.

Transfer of antibiotic-resistant bacteria via ballast water with a special focus on multiple antibiotic-resistant bacteria: A survey from an inland port in the Yangtze River.

Ship ballast water can transfer harmful organisms, including antibiotic-resistant bacteria (ARB), among geographically isolated waters. In this study, the presence and composition of ARB and multiple ARB (MARB) were investigated in the ballast waters of 30 vessels sailing to the Port of Jiangyin (Jiangsu Province, China). ARB were detected in 83.

Elucidating the role of earthworms in NO emission and production pathway during vermicomposting of sewage sludge and rice straw.

Vermicomposting is a sustainable option for the recycling of biodegradable organic waste. However, it also produces nitrous oxide (NO), which is a highly potent greenhouse gas. In this study, the NO stable isotope and functional genes for nitrogen cycling were determined to investigate the sources of NO during vermicomposting.

Vessel transport of antibiotic resistance genes across oceans and its implications for ballast water management.

The emergence and spread of antibiotic resistance are major threats to ecosystems and human health. Transoceanic channels (e.g.

Effects of holding time on the diversity and composition of potential pathogenic bacteria in ship ballast water.

Ballast water is a common vector for the transport of invasive species to new marine and aquatic environments. We used a metagenomics approach to examine the diversity and composition of potential pathogens communities in ballast water from ships in the route of China- Southeast Asia (CSEA). 16 kinds of potential pathogenic genus were detected in the ballast water.

Effects of earthworms on nitrogen transformation and the correspond genes (amoA and nirS) in vermicomposting of sewage sludge and rice straw.

The effects of earthworms on nitrogen transformation and the responsible functional genes during disposal of sewage sludge and rice straw were investigated in this study. Vermicomposting resulted in the lower pH and total organic carbon (TOC) compared to the control treatment without earthworms. Moreover, the presence of earthworms could promote the nitrogen mineralization and nitrification process in vermicomposting.

Effects of C/N ratio and earthworms on greenhouse gas emissions during vermicomposting of sewage sludge.

The emissions of greenhouse gases (CO, CH, and NO) during bio-stabilization of sewage sludge under different C/N ratios with/without Eisenia fetida were evaluated in this study. Vermicomposting led to the more significant reductions of pH, TOC and C/N ratio compared to the control treatment without earthworms. C/N ratio had a significant effect on the emission of NO, whereas its influences on CO or CH emission were not obvious.

Abundances and profiles of antibiotic resistance genes as well as co-occurrences with human bacterial pathogens in ship ballast tank sediments from a shipyard in Jiangsu Province, China.

Ship ballasting operations may transfer harmful aquatic organisms across global ocean. This study aims to reveal the occurrences and abundances of antibiotic resistance genes (ARGs) and human bacterial pathogens (HBPs) in ballast tank sediments. Nine samples were collected and respectively analyzed by real-time quantitative PCR and high-throughput sequencing technologies.

Exploring the effects of earthworms on bacterial profiles during vermicomposting process of sewage sludge and cattle dung with high-throughput sequencing.

This study aims to reveal the effects of earthworms (Eisenia fetida) on bacterial profiles during the vermicomposting process of sewage sludge and cattle dung with the high-throughput sequencing technology. The earthworms could accelerate organic degradation and improve the stabilization process. Moreover, the addition of earthworms not only affected the bacterial numbers, but also increased the bacterial community diversity.

Composition and influencing factors of bacterial communities in ballast tank sediments: Implications for ballast water and sediment management.

This study aims to reveal the composition and influencing factors of bacterial communities in ballast tank sediments. Nine samples were collected and their 16S rRNA gene sequences were analyzed by high-throughput sequencing. The analysis results showed the Shannon index in ballast tank sediments was in the range of 5.

Occurrences, composition profiles and source identifications of polycyclic aromatic hydrocarbons (PAHs), polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs) in ship ballast sediments.

The aim of this study was to investigate the levels of persistent organic pollutants (POPs) including polycyclic aromatic hydrocarbons (PAHs), polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs) in ship ballast sediments. The ballast sediment samples were collected from six merchant ships docked in 2015 in Jiangyin City, China. Ballast sediments represent a potential vector for the transport of POPs and invasive species between marine environments.

Pollution characteristics and ecological risk of heavy metals in ballast tank sediment.

This study was conducted to illustrate the contents and potential ecological risk of heavy metals in ballast tank sediment. Ballast sediment samples were collected from six ships during their stay in shipyard, and the heavy metals were determined by inductive coupled plasma emission spectrometer. Results showed that high concentrations of heavy metals were detected in all six sediment samples following the order: Zn > Cu > Pb > Cr > As > Cd > Hg.

Speciation and transformation of heavy metals during vermicomposting of animal manure.

This work was conducted to evaluate the effects of vermicomposting on the speciation and mobility of heavy metals (Zn, Pb, Cr, and Cu) in cattle dung (CD) and pig manure (PM) using tessier sequential extraction method. Results showed that the pH, total organic carbon and C/N ratio were reduced, while the electric conductivity and humic acid increased after 90days vermicomposting. Moreover, the addition of earthworm could accelerate organic stabilization in vermicomposting.

Pyrosequencing reveals bacterial community differences in composting and vermicomposting on the stabilization of mixed sewage sludge and cattle dung.

This study aimed to compare the microbial community structures and compositions in composting and vermicomposting processes. We applied 454 high-throughput pyrosequencing to analyze the 16S rRNA gene of bacteria obtained from bio-stabilization of sewage sludge and cattle dung. Results demonstrated that vermicomposting process presented higher operational taxonomic units and bacterial diversity than the composting.

Tracking the composition and transformation of humic and fulvic acids during vermicomposting of sewage sludge by elemental analysis and fluorescence excitation-emission matrix.

Sewage sludge (T1) and the mixture of sewage sludge and cattle dung (T2) were vermicomposted with Eisenia fetida, respectively. The transformation of humic acid (HA) and fulvic acid (FA) extracted from these two treatments were evaluated by a series of chemical and spectroscopic methods. Results indicated that the vermicomposting decreased pH, TOC, and C/N ratio, and increased EC, total extractable C, and HA contents.

Towards understanding the effects of additives on the vermicomposting of sewage sludge.

This work evaluated the effects of additives on the chemical properties of the final products (vermicompost) from vermicomposting of sewage sludge and the adaptable characteristics of Eisenia fetida during the process. An experimental design with different ratios of sewage sludge and the additives (cattle dung or pig manure) was conducted. The results showed that the vermicomposting reduced total organic carbon and the quotient of total organic carbon to total nitrogen (C/N ratio) of the initial mixtures and enhanced the stability and agronomical value of the final products.

Towards understanding the stabilization process in vermicomposting using PARAFAC analysis of fluorescence spectra.

In this study, fluorescence excitation-emission matrix (EEM) combined with parallel factor analysis (PARAFAC) was employed to trace the behavior of water extractable organic matter and assess the stabilization process during vermicomposting of sewage sludge and cattle dung. Experiments using different mixing ratios of sewage sludge and cattle dung were conducted using Eisenia fetida. The results showed that vermicomposting reduced the DOC, DOC/DON ratio and ammonia, while increased the nitrate content.

Feeding behavior and trophic relationship of earthworms and other predators in vermifiltration system for liquid-state sludge stabilization using fatty acid profiles.

The sludge reduction capability (VSS reduction) of vermifilter (VF) was 14.7% higher than that of conventional biofilter (BF) due to the fact that there was a net loss of biomass and energy when the food web in VF is extended. Therefore, feeding behavior and trophic relationship of earthworms and other predators (leeches, lymnaeidaes and limaxes) in VF were investigated using fatty acid (FA) profiles for the first time.

Tracking the composition and dominant components of the microbial community via polymerase chain reaction-denaturing gradient gel electrophoresis and fluorescence in situ hybridization during vermiconversion for liquid-state excess sludge stabilization.

To quantitatively explore the microbial community modified by earthworms, a vermifilter (VF, with earthworms) and a conventional biofilter (BF, without earthworms) were continuously operated to stabilize excess sludge. The results demonstrated a positive role imposed by earthworms on compositions and dominant components of microbial community in the VF. For one thing, the phyla Actinobacteria and Acidobacteria were only detected in the VF, which might explain for the higher Shannon index of bacteria in the VF (H = 2.