The occurrence of harmful algal blooms (HABs) in freshwater environments has been expanded worldwide with growing frequency and severity. HABs can pose a threat to public water supplies, raising concerns about safety of treated water. Many studies have provided valuable information about the impacts of HABs and management strategies on the early-stage treatment processes (e.
View Article and Find Full Text PDFThe occurrence of antibiotic-resistant bacteria (ARB) in wastewater treatment plants (WWTPs) has become an occupational and environmental concern. WWTPs are engineered systems that treat wastewater to meet public health standards before release into the environment. The residuals, as either effluent or solids, are then discharged or beneficially recycled into the environment.
View Article and Find Full Text PDFAppl Microbiol Biotechnol
February 2023
Accidental oil spills can result in catastrophic ecological insults and therefore require rapid intervention to mitigate the potential impacts to aquatic ecosystems. One of the largest oil spills, known as the Deepwater Horizon oil spill, occurred in the Spring of 2010 near the coast of Louisiana (USA) due to an explosion during oil drilling activities. Millions of gallons of oil were released into the Gulf of Mexico, impacting thousands of ocean miles and coastal areas linked to the gulf.
View Article and Find Full Text PDFThe use of enterococci as a fecal indicator bacterial group for public health risk assessment has been brought into question by recent studies showing that "naturalized" populations of Enterococcus faecalis exist in the extraenteric environment. The extent to which these naturalized E. faecalis organisms can confound water quality monitoring is unclear.
View Article and Find Full Text PDFBackground: Rivers and lakes are used for multiple purposes such as for drinking water (DW) production, recreation, and as recipients of wastewater from various sources. The deterioration of surface water quality with wastewater is well-known, but less is known about the bacterial community dynamics in the affected surface waters. Understanding the bacterial community characteristics -from the source of contamination, through the watershed to the DW production process-may help safeguard human health and the environment.
View Article and Find Full Text PDFMicrobial drinking water quality in premise plumbing systems (PPSs) strongly affects public health. Bacterial community structure is the essential aspect of microbial water quality. Studies have elucidated the microbial community structure in cold tap water, while the microbial community structures in hot tap and shower water are poorly understood.
View Article and Find Full Text PDFCalanoid copepods are integral to aquatic food webs and may drive the bioaccumulation of toxins and heavy metals, spread of infectious diseases, and occurrence of toxic cyanobacterial harmful algal blooms (HABs) in freshwater aquatic systems. However, interrelationships between copepod and cyanobacterial population dynamics and ecophysiology remain unclear. Insights into these relationships are important to aquatic resource management, as they may help guide mitigation efforts.
View Article and Find Full Text PDFMicrobial fuel cells (MFCs) have recently been applied to generate electricity from oily wastewater. Although MFCs that utilize microalgae to provide a self-supporting oxygen (O) supply at the cathode have been well discussed, those with microalgae at the anode as an active biomass for treating wastewater and producing electrons are still poorly studied and understood. Here, we demonstrated a bilgewater treatment using single- and double-chamber microalgal fuel cells (SMAFC and DMAFC) capable of generating energy with a novel microalgal strain () that was initially isolated from oily wastewater.
View Article and Find Full Text PDFTo address the adverse effects of harmful algal blooms, there are increased demands over the implementation of ozone coupled with biologically active carbon (BAC) filters in the drinking water treatment plants. Although the microbial biofilms are vital elements to support the proper performance of BAC filters, except for taxonomic affiliations, little is known about the assembly mechanisms of microbial communities in the full-scale BAC filters. This study aimed to examine how the assembly processes and their associated factors (e.
View Article and Find Full Text PDFThe occurrence of harmful algal blooms dominated by toxic cyanobacteria has induced continuous loadings of algal organic matter (AOM) and toxins in drinking water treatment plants. However, the impact of AOM on the active biofilms and microbial community structures of biologically-active filtration (BAF), which directly affects the contaminant removal, is not well understood. In this study, we systematically examined the effects of AOM on BAF performance and bacterial biofilm formation over 240 days, tracing the removal of specific AOM components, a cyanotoxin [microcystin-LR (MC-LR)], and microbial community responses.
View Article and Find Full Text PDFThere are increased concerns over the contributions of biofilms to disinfection byproduct (DBP) formation in engineered water systems (EWS). However, monitoring the biomolecular characteristics of biofilms to understand their impacts on DBP formation has been a great challenge as it requires complex analytical techniques. This study aimed to examine the applicability of fluorescence excitation-emission matrices (EEMs) coupled with parallel factor analysis (PARAFAC) to assess the chemical compositions and DBP formation of biofilms.
View Article and Find Full Text PDFGut microbiota can have important effects on host health, but explanatory factors and pathways that determine gut microbial composition can differ among host lineages. In mammals, host phylogeny is one of the main drivers of gut microbiota, a result of vertical transfer of microbiota during birth. In birds, it is less clear what the drivers might be, but both phylogeny and environmental factors may play a role.
View Article and Find Full Text PDFspp. are commensal organisms in avian species and are one of the leading causes of bacterial foodborne human diarrheal disease worldwide. We report the draft genome sequences of , , and strains isolated from California gull () excreta collected from a California beach.
View Article and Find Full Text PDFThere is growing interest in the use of DNA barcoding and metabarcoding approaches to aid biological assessments and monitoring of waterbodies. While biodiversity measured by morphology and by DNA often has been found correlated, few studies have compared DNA data to established measures of impairment such as multimetric pollution tolerance indices used by many bioassessment programs. We incorporated environmental DNA (eDNA) metabarcoding of seston into a rigorous watershed-scale biological assessment of an urban stream to examine the extent to which eDNA richness and diversity patterns were correlated with multimetric indices and ecological impairment status designations.
View Article and Find Full Text PDFPublic health data show that a significant fraction of the nation's waterborne disease outbreaks are attributable to premise plumbing. We report the draft genome sequences of seven serogroup 1 isolates from hot water lines of a large building. Genomic analysis identified the isolates as belonging to sequence type 1.
View Article and Find Full Text PDFIncreased loading of algal organic matter (AOM) during harmful algal blooms not only burdens water treatment processes but also challenges safe drinking water delivery. While organic constituents promote biofilm growth in drinking water distribution systems (DWDS), the effects of AOM on biofilm formation in DWDS are not well understood. Herein, three parallel biofilm reactors were used to assess and compare how treated AOM- and humic substance (HS)-impacted bulk water, and R2A medium (a control) affect biofilm development for 168 days.
View Article and Find Full Text PDFCyanobacterial blooms are intensifying global ecological hazards. The fine structure and dynamics of bloom community are critical to understanding bloom development but little understood. Here, the questions whether dominant bloomers have high diversity and whether dominant OTUs (operational taxonomical units) compete with one another were addressed.
View Article and Find Full Text PDFConventional biological nitrogen removal (BNR), comprised of nitrification and denitrification, is traditionally employed in wastewater treatment plants (WWTPs) to prevent eutrophication in receiving water bodies. More recently, the combination of selective ammonia to nitrite oxidation (nitritation) and autotrophic anaerobic ammonia oxidation (anammox), collectively termed deammonification, has also emerged as a possible energy- and cost-effective BNR alternative. Herein, we analyzed microbial diversity and functional potential within 13 BNR processes in the United States, Denmark, and Singapore operated with varying reactor configuration, design, and operational parameters.
View Article and Find Full Text PDFIntestinal enterococci indicate the fecal contamination of bathing waters. This study defines the performance characteristics of the reference method ISO 7899-2:2000 with water samples collected from inland and coastal bathing areas in Finland. From a total of 341 bacterial isolates grown on Slanetz and Bartley medium, 63.
View Article and Find Full Text PDFThe Integrated Fixed-Film Activated Sludge (IFAS) process is an advanced biological wastewater treatment process that integrates biofilm carriers within conventional activated sludge to uncouple the sludge retention time for nitrifiers and heterotrophic bacteria. In this study, we incorporated microalgae into the IFAS configuration for photo-oxygenation and evaluated the symbiotic reaction between microalgae and bacteria for both suspended solids and IFAS biofilm media. In a sequencing batch mode, the microalgae-IFAS system removed more than 99% ammonia and 51% phosphorous without the need for mechanical aeration.
View Article and Find Full Text PDFTreatability experiments were conducted to determine the biodegradation of diluted bitumen (dilbit) at 5 and 25 °C for 72 and 60 days, respectively. Microbial consortia obtained from the Kalamazoo River Enbridge Energy spill site were enriched on dilbit at both 5 (cryo) and 25 (meso) ºC. On every sampling day, triplicates were sacrificed and residual hydrocarbon concentrations (alkanes and polycyclic aromatic hydrocarbons) were determined by GCMS/MS.
View Article and Find Full Text PDFEnviron Sci Technol Lett
January 2018
Complete ammonia oxidation (comammox) to nitrate by certain Nitrospira-lineage bacteria (CMX) could contribute to overall nitrogen cycling in engineered biological nitrogen removal (BNR) processes in addition to the more well-documented nitrogen transformations by ammonia-oxidizing bacteria (AOB), nitrite-oxidizing bacteria (NOB), and anaerobic ammonia-oxidizing (anammox) bacteria (AMX). A metagenomic survey was conducted to quantify the presence and elucidate the potential functionality of CMX in 16 full-scale BNR configurations treating mainstream or sidestream wastewater. CMX proposed to date were combined with previously published AOB, NOB, and AMX genomes to create an expanded database for alignment of metagenomic reads.
View Article and Find Full Text PDFThe occurrence and densities of opportunistic pathogens (OPs), the microbial community structure, and their associations with sediment elements from eight water storage tanks in Ohio, West Virginia, and Texas were investigated. The elemental composition of sediments was measured through X-ray fluorescence (XRF) spectra. The occurrence and densities of OPs and amoeba hosts (i.
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