scholarly journals Profiling Bacterial Diversity and Potential Pathogens in Wastewater Treatment Plants Using High-Throughput Sequencing Analysis

2019 ◽  
Vol 7 (11) ◽  
pp. 506 ◽  
Author(s):  
Cecilia Oluseyi Osunmakinde ◽  
Ramganesh Selvarajan ◽  
Bhekie B. Mamba ◽  
Titus A.M. Msagati
Keyword(s):  
Wastewater Treatment ◽  
Pathogenic Bacteria ◽  
High Throughput Sequencing ◽  
Wastewater Treatment Plants ◽  
Bacterial Pathogens ◽  
Size Analysis ◽  
Sequencing Analysis ◽  
Linear Discriminant ◽  
Treated Effluent ◽  
Wastewater Treatment Systems

Next-generation sequencing provides new insights into the diversity and structure of bacterial communities, as well as the fate of pathogens in wastewater treatment systems. In this study, the bacterial community structure and the presence of pathogenic bacteria in three wastewater treatment plants across Gauteng province in South Africa were studied. The physicochemical results indicated that the quality of wastewater varies considerably from one plant to the others. Proteobacteria, Actinobacteria, Firmicutes, and Chloroflexi were the dominant phyla across the three wastewater treatment plants, while Alphaproteobacteria, Actinobacteria, Bacilli, and Clostridia were the dominant classes. The dominant bacterial functions were highly associated with carbohydrate, energy, and amino acid metabolism. In addition, potential pathogenic bacterial members identified from the influent/effluent samples included Roseomonas, Bacillus, Pseudomonas, Clostridium, Mycobacterium, Methylobacterium, and Aeromonas. The results of linear discriminant analysis (LDA) effect size analysis also confirmed that these bacterial pathogens were significantly abundant in the wastewater treatment systems. Further, the results of this study highlighted that the presence of bacterial pathogens in treated effluent pose a potential contamination risk, transmitted through soil, agriculture, water, or sediments. There is thus a need for continuous monitoring of potential pathogens in wastewater treatment plants (WWTPs) in order to minimize public health risk.

scholarly journals Bacteria from the Genus Arcobacter Are Abundant in Effluent from Wastewater Treatment Plants

2020 ◽  
Vol 86 (9) ◽  
Author(s):  
Jannie Munk Kristensen ◽  
Marta Nierychlo ◽  
Mads Albertsen ◽  
Per Halkjær Nielsen
Keyword(s):  
Wastewater Treatment ◽  
Pathogenic Bacteria ◽  
Municipal Wastewater ◽  
Wastewater Treatment Plants ◽  
Amplicon Sequencing ◽  
Rrna Gene ◽  
Content Type ◽  
Effluent Quality ◽  
Culture Independent ◽  
Influent Wastewater

ABSTRACT Pathogenic bacteria in wastewater are generally considered to be efficiently removed in biological wastewater treatment plants. This understanding is almost solely based on culture-based control measures, and here we show, by applying culture-independent methods, that the removal of species in the genus Arcobacter was less effective than for many other abundant genera in the influent wastewater. Arcobacter was one of the most abundant genera in influent wastewater at 14 municipal wastewater treatment plants and was also abundant in the “clean” effluent from all the plants, reaching up to 30% of all bacteria as analyzed by 16S rRNA gene amplicon sequencing. Metagenomic analyses, culturing, genome sequencing of Arcobacter isolates, and visualization by fluorescent in situ hybridization (FISH) confirmed the presence of the human-pathogenic Arcobacter cryaerophilus and A. butzleri in both influent and effluent. The main reason for the high relative abundance in the effluent was probably that Arcobacter cells, compared to those of other abundant genera in the influent, did not flocculate and attach well to the activated sludge flocs, leaving a relatively large fraction dispersed in the water phase. The study shows there is an urgent need for new standardized culture-independent measurements of pathogens in effluent wastewaters, e.g., amplicon sequencing, and an investigation of the problem on a global scale to quantify the risk for humans and livestock. IMPORTANCE The genus Arcobacter was unexpectedly abundant in the effluent from 14 Danish wastewater treatment plants treating municipal wastewater, and the species included the human-pathogenic A. cryaerophilus and A. butzleri. Recent studies have shown that Arcobacter is common in wastewater worldwide, so the study indicates that discharge of members of the genus Arcobacter may be a global problem, and further studies are needed to quantify the risk and potentially minimize the discharge. The study also shows that culture-based analyses are insufficient for proper effluent quality control, and new standardized culture-independent measurements of effluent quality encompassing most pathogens should be considered.

scholarly journals Occurrence of intestinal parasites in sewage samples and efficiency of wastewater treatment systems in Tunisia

2018 ◽  
Vol 53 (2) ◽  
pp. 86-101 ◽  
Author(s):  
S. Sabbahi ◽  
M. Trad ◽  
L. Ben Ayed ◽  
N. Marzougui
Keyword(s):  
Wastewater Treatment ◽  
Wastewater Treatment Plants ◽  
Multiple Correspondence Analysis ◽  
Intestinal Parasites ◽  
Sampling Period ◽  
Hymenolepis Diminuta ◽  
Helminth Eggs ◽  
Wastewater Samples ◽  
One Year ◽  
Wastewater Treatment Systems

Abstract The present study aimed to: (i) identify helminth eggs and protozoan cysts in wastewater samples to which both human and animals could be exposed when they are reused in agriculture; and (ii) evaluate the efficiency of their removal by two wastewater treatment systems (activated sludge and lagoon). For these purposes, 234 wastewater samples (117 raw, 117 treated) were collected from 20 wastewater treatment plants (WWTPs) in Tunisia over a one-year sampling period. Parasitic load was enumerated by the modified Bailenger method. The results showed that helminth eggs found were Nematodes mainly represented by Ascaris sp. (95%), Hookworm species (50%), and Enterobius vermicularis (45%). For Cestodes, species identified were Taeniid eggs (85%), Hymenolepis nana (70%), Hymenolepis diminuta (55%) and digestive Strongyles. Among protozoa, Giardia sp., Entamoeba histolytica/dispar/moshkovskii and Entamoeba coli cysts were found in 100% of raw wastewater samples. The overall removal efficiency of helminth eggs and protozoan cysts in the treatment plants ranged from 56.5 to 100% and from 50.4 to 95.5%, respectively. The result from Multiple Correspondence Analysis (MCA) shows that the close clustering of the parasitic mean removal levels indicates that there is little difference in wastewater treatment processes between the WWTPs examined.

scholarly journals Evaluation of the Biofilm Forming Capacities of Bacterial Isolates Recovered in Raw and Treated Effluent from Wastewater Treatment Plant of Ahmadu Bello University Zaria, Nigeria

2019 ◽  
Vol 23 (10) ◽  
pp. 1783-1786
Author(s):  
MI Ugwoke ◽  
DA Machido ◽  
MB Tijjani
Keyword(s):  
Wastewater Treatment ◽  
Congo Red ◽  
Antimicrobial Agents ◽  
Wastewater Treatment Plants ◽  
Screening Method ◽  
Treatment Plant ◽  
Bacterial Isolates ◽  
Biofilm Production ◽  
Treated Effluent ◽  
Raw Wastewater

Biofilm producing bacteria are associated with many recalcitrant infections and are highly resistant to antimicrobial agents, hence notoriously difficult to eradicate. This study aimed at determining the biofilm forming capacities of bacterial isolates recovered in the raw wastewater and treated effluent from Wastewater Treatment Plants of Ahmadu Bello University Zaria using Tube Method (TM) and Congo Red Agar (CRA) method; and from the results, among the isolates recovered from the raw wastewater, TM detected 62.5% isolates as positive and 37.5% as negative for biofilm production, CRA detected 37.5% isolates as positive and 62.5% as negative for biofilm production. TM also demonstrated to be more suitable in detecting biofilm producing bacterial isolates from the treated effluent were it detected 50% isolates as positive and 50% as negative. However, CRA detected only 12.5% isolates as positive and 87.5% as negative for biofilm production. We therefore, conclude that the TM is more efficient and reliable for detection of biofilm producing bacteria in the laboratory when compared to CRA method and can be recommended as one of the suitable standard screening method for the detection of biofilm producing bacteria in laboratories.Keywords: Biofilm; Bacteria; Congo red agar and Tube method

A review of the detection, fate and effects of engineered nanomaterials in wastewater treatment plants

2013 ◽  
Vol 68 (7) ◽  
pp. 1440-1453 ◽  
Author(s):  
Peta A. Neale ◽  
Åsa K. Jämting ◽  
Beate I. Escher ◽  
Jan Herrmann
Keyword(s):  
Wastewater Treatment ◽  
Surface Coating ◽  
Wastewater Treatment Plants ◽  
Engineered Nanomaterials ◽  
Detection Methods ◽  
Laboratory Studies ◽  
Test Conditions ◽  
Treated Effluent ◽  
Low Concentrations ◽  
Wide Range

Engineered nanomaterials (ENMs) are increasingly found in a wide range of products and processes, and consequently increasing loads are expected to reach wastewater treatment plants (WWTPs). To better assess the potential risk of ENMs to the environment via input through WWTP effluents, this review considers ENM detection methods, fate in WWTPs and potential effects on biota exposed to wastewater associated ENMs. Characterising ENMs in complex matrices presents many challenges, especially at low concentrations. Combining separation methods with techniques to assess particle size and chemical composition appears to be the most suitable approach for wastewater. In a range of studies, the majority of ENMs are removed from the aqueous phase by flocculation and sedimentation and remain in the sludge. However, ENM surface coating and the presence of organic matter and surfactants can alter removal. ENMs may affect biota via discharge of treated effluent to the aquatic environment or by application of sewage sludge to soil, although observed effects in laboratory studies only occurred at concentrations several orders of magnitude higher than the expected environmental levels. More realistic experimental designs with improved quantification of ENM properties under the selected test conditions are required to better understand the fate and effect of ENMs associated with WWTPs.

scholarly journals Effects of Helicobacter pylori Infection on the Oral Microbiota of Reflux Esophagitis Patients

2021 ◽  
Vol 11 ◽  
Author(s):  
Tian Liang ◽  
Fang Liu ◽  
Lijun Liu ◽  
Zhiying Zhang ◽  
Wenxue Dong ◽  
...  
Keyword(s):  
Helicobacter Pylori ◽  
Reflux Esophagitis ◽  
Beta Diversity ◽  
High Throughput Sequencing ◽  
Alpha Diversity ◽  
Vital Role ◽  
Size Analysis ◽  
Oral Microbiota ◽  
Linear Discriminant ◽  
Microbial Network

The human oral microbiota plays a vital role in maintaining metabolic homeostasis. To explore the relationship between Helicobacter pylori (Hp) and reflux esophagitis, we collected 86 saliva samples from reflux esophagitis patients (RE group) and 106 saliva samples from healthy people (C group) for a high-throughput sequencing comparison. No difference in alpha diversity was detected between the RE and the C groups, but beta diversity of the RE group was higher than the C group. Bacteroidetes was more abundant in the RE group, whereas Firmicutes was more abundant in the C group. The linear discriminant analysis effect size analysis demonstrated that the biomarkers of the RE group were Prevotella, Veillonella, Leptotrichia, and Actinomyces, and the biomarkers of the C group were Lautropia, Gemella, Rothia, and Streptococcus. The oral microbial network structure of the C group was more complex than that of the RE group. Second, to explore the effect of Hp on the oral microbiota of RE patients, we performed the 14C-urea breath test on 45 of the 86 RE patients. We compared the oral microbiota of 33 Hp-infected reflux esophagitis patients (REHpp group) and 12 non-Hp-infected reflux esophagitis patients (REHpn group). No difference in alpha diversity was observed between the REHpn and REHpp groups, and beta diversity of the REHpp group was significantly lower than that of the REHpn group. The biomarkers in the REHpp group were Veillonella, Haemophilus, Selenomonas, Megasphaera, Oribacterium, Butyrivibrio, and Campylobacter; and the biomarker in the REHpn group was Stomatobaculum. Megasphaera was positively correlated with Veillonella in the microbial network of the REHpp group. The main finding of this study is that RE disturbs the human oral microbiota, such as increased beta diversity. Hp infection may inhibit this disorderly trend.

scholarly journals Ultraviolet disinfection impacts the microbial community composition and function of treated wastewater effluent and the receiving urban river

PeerJ ◽  
2019 ◽  
Vol 7 ◽  
pp. e7455 ◽  
Author(s):  
Imrose Kauser ◽  
Mark Ciesielski ◽  
Rachel S. Poretsky
Keyword(s):  
Wastewater Treatment ◽  
Microbial Community ◽  
River Water ◽  
Wastewater Treatment Plants ◽  
Microbial Community Composition ◽  
The United States ◽  
Treated Wastewater ◽  
Coliform Bacteria ◽  
Uv Disinfection ◽  
Treated Effluent

Background In the United States, an estimated 14,748 wastewater treatment plants (WWTPs) provide wastewater collection, treatment, and disposal service to more than 230 million people. The quality of treated wastewater is often assessed by the presence or absence of fecal indicator bacteria. UV disinfection of wastewater is a common final treatment step used by many wastewater treatment plants in order to reduce fecal coliform bacteria and other pathogens; however, its potential impacts on the total effluent bacterial community are seemingly varied. This is especially important given that urban WWTPs typically return treated effluent to coastal and riverine environments and thus are a major source of microorganisms, genes, and chemical compounds to these systems. Following rainfall, stormflow conditions can result in substantial increases to effluent flow into combined systems. Methods Here, we conducted a lab-scale UV disinfection on WWTP effluent using UV dosage of 100 mJ/cm2 and monitored the active microbiome in UV-treated effluent and untreated effluent over the course of 48 h post-exposure using 16S rRNA sequencing. In addition, we simulated stormflow conditions with effluent UV-treated and untreated effluent additions to river water and compared the microbial communities to those in baseflow river water. We also tracked the functional profiles of genes involved in tetracycline resistance (tetW) and nitrification (amoA) in these microcosms using RT-qPCR. Results We showed that while some organisms, such as members of the Bacteroidetes, are inhibited by UV disinfection and overall diversity of the microbial community decreases following treatment, many organisms not only survive, but remain active. These include common WWTP-derived organisms such as Comamonadaceae and Pseudomonas. When combined with river water to mimic stormflow conditions, these organisms can persist in the environment and potentially enhance microbial functions such as nitrification and antibiotic resistance.

scholarly journals Microbial Profiles of Retail Pacific Oysters (Crassostrea gigas) From Guangdong Province, China

2021 ◽  
Vol 12 ◽  
Author(s):  
Mingjia Yu ◽  
Xiaobo Wang ◽  
Aixian Yan
Keyword(s):  
Microbial Communities ◽  
Crassostrea Gigas ◽  
Pathogenic Bacteria ◽  
High Throughput Sequencing ◽  
Vibrio Vulnificus ◽  
Foodborne Pathogen ◽  
Guangdong Province ◽  
Sequencing Analysis ◽  
Alpha And Beta Diversity ◽  
Pacific Oysters

Oysters are one of the main aquatic products sold in coastal areas worldwide and are popular among consumers because of their delicious taste and nutritional value. However, the microorganisms present in oysters may pose health risks to consumers. In this study, the microbial communities of Pacific oysters (Crassostrea gigas) collected from aquatic product markets in three cities (Guangzhou, Zhuhai, and Jiangmen) of Guangdong Province, China, where raw oysters are popular, were investigated. The plate counts of viable bacteria in oysters collected in the three cities were all approximately 2 log colony-forming units/g. High-throughput sequencing analysis of the V3–V4 region of the 16Sribosomal DNA gene showed a high level of microbial diversity in oysters, as evidenced by both alpha and beta diversity analysis. Proteobacteria, Bacteroidetes, and Firmicutes were the dominant phyla of the microorganisms present in these samples. A variety of pathogenic bacteria, including the fatal foodborne pathogen Vibrio vulnificus, were found, and Vibrio was the dominant genus. Additionally, the relationship between other microbial species and pathogenic microorganisms may be mostly symbiotic in oysters. These data provide insights into the microbial communities of retail oysters in the Guangdong region and indicate a considerable risk related to the consumption of raw oysters.

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