scholarly journals Water and Wastewater Disinfection with Peracetic Acid and UV Radiation and Using Advanced Oxidative Process PAA/UV

2015 ◽  
Vol 2015 ◽  
pp. 1-7 ◽  
Author(s):  
Jeanette Beber de Souza ◽  
Fernanda Queiroz Valdez ◽  
Rhuan Felipe Jeranoski ◽  
Carlos Magno de Sousa Vidal ◽  
Grasiele Soares Cavallini
Keyword(s):  
Uv Radiation ◽  
Peracetic Acid ◽  
Combined Method ◽  
Experimental Conditions ◽  
E Coli ◽  
Wastewater Disinfection ◽  
Combined Action ◽  
Oxidative Processes ◽  
Water And Wastewater ◽  
The Individual

The individual methods of disinfection peracetic acid (PAA) and UV radiation and combined process PAA/UV in water (synthetic) and sanitary wastewater were employed to verify the individual and combined action of these advanced oxidative processes on the effectiveness of inactivation of microorganisms indicators of fecal contaminationE. coli, total coliforms (in the case of sanitary wastewater), and coliphages (such as virus indicators). Under the experimental conditions investigated, doses of 2, 3, and 4 mg/L of PAA and contact time of 10 minutes and 60 and 90 s exposure to UV radiation, the results indicated that the combined method PAA/UV provided superior efficacy when compared to individual methods of disinfection.

Inactivation of E. coli, Enterococcus spp., somatic coliphage, and Cryptosporidium parvum in wastewater by peracetic acid (PAA), sodium hypochlorite, and combined PAA-ultraviolet disinfection

2020 ◽  
Vol 6 (1) ◽  
pp. 197-209 ◽  
Author(s):  
Abdulrahman H. Hassaballah ◽  
Tanmay Bhatt ◽  
Jeremy Nyitrai ◽  
Ning Dai ◽  
Lauren Sassoubre
Keyword(s):  
Sodium Hypochlorite ◽  
Cryptosporidium Parvum ◽  
Peracetic Acid ◽  
Ecosystem Health ◽  
Ultraviolet Disinfection ◽  
E Coli ◽  
Enterococcus Spp ◽  
Wastewater Disinfection ◽  
Somatic Coliphage

Wastewater disinfection is important to protect human and ecosystem health.

A pilot-scale study of peracetic acid and ultraviolet light for wastewater disinfection

2019 ◽  
Vol 5 (8) ◽  
pp. 1453-1463 ◽  
Author(s):  
Abdulrahman H. Hassaballah ◽  
Jeremy Nyitrai ◽  
Christine H. Hart ◽  
Ning Dai ◽  
Lauren M. Sassoubre
Keyword(s):  
Ultraviolet Light ◽  
Peracetic Acid ◽  
Pilot Scale ◽  
Fecal Coliforms ◽  
Treated Wastewater ◽  
E Coli ◽  
Wastewater Disinfection ◽  
Somatic Coliphage

At the pilot-scale, peracetic acid effectively inactivates fecal coliforms,E. coliandEnterococcusspp. in secondary and tertiary treated wastewater. The addition of UV to PAA treatment increases inactivation of somatic coliphage.

scholarly journals Simultaneous removal of estrogens and pathogens from secondary treated wastewater by solar photocatalytic treatment

2014 ◽  
Vol 16 (3) ◽  
pp. 543-552 ◽  
Keyword(s):  
Solar Radiation ◽  
Estrogenic Activity ◽  
Treated Wastewater ◽  
Simultaneous Removal ◽  
E Coli ◽  
Water Matrix ◽  
Treated Effluent ◽  
Emerging Compounds ◽  
Wastewater Disinfection ◽  
Water And Wastewater

<p>Recently, the fate of emerging compounds in environmentally relevant samples has attracted considerable attention. Solar semiconductor photocatalysis may offer an appealing methodology to treat such contaminants. At the same time the use of solar photocatalysis for water and wastewater disinfection is a topic well-documented in the literature. In this respect, the simultaneous degradation of synthetic estrogen 17α-ethynylestradiol (EE2) and <em>Escherichia coli </em>removal employing simulated solar radiation and TiO<sub>2</sub> as the photocatalyst was investigated. In general, the more complex the water matrix is the slower <em>E. coli</em> removal becomes, while the presence of <em>E. coli</em> in the reaction mixture did not obstruct EE2 removal.</p> <div> <p>Although EE2 removal occurred relatively fast, overall estrogenic activity was only partially removed. This implies that other species inherently present in the effluent and/or some photocatalytic transformation by-products may be proportionately more estrogenic than EE2. Overall, the use of solar radiation can constitute an advantageous treatment strategy for the simultaneous removal of micro-pollutants and pathogens from secondary treated effluent.</p> </div> <p>&nbsp;</p>

scholarly journals Efficacy of integrated ultraviolet ultrasonic technologies in the removal of erythromycin- and quinolone-resistant Escherichia coli from domestic wastewater through a laboratory-based experiment

2019 ◽  
Vol 9 (3) ◽  
pp. 571-580
Author(s):  
Owassa Dza Rebecca Annisha ◽  
Zifu Li ◽  
Xiaoqin Zhou ◽  
Ngomah Madgil Don Stenay Junior ◽  
Oscar Omondi Donde
Keyword(s):  
Escherichia Coli ◽  
Uv Radiation ◽  
Bacterial Resistance ◽  
Domestic Wastewater ◽  
Potential Effect ◽  
Integrative Approach ◽  
Wastewater Purification ◽  
E Coli ◽  
Antibiotic Drugs ◽  
The Individual

Abstract Bacterial resistance to antibiotics has become a common occurrence especially in areas where antibiotic drugs are widely used. Moreover, the potential effect of antibiotic pollution and the presence of antibiotic-resistant genes (ARGs) on the composition of bacterial communities in the ecosystems continue to degrade the quality of most ecosystems. Despite the use of ultraviolet (UV) radiation and ultrasound (US) technologies in wastewater purification, little is known on their application in the elimination of fecal pathogenic microorganisms such as Escherichia coli. Moreover, their individual and combined potential in the elimination of erythromycin- and quinolone-resistant E. coli is a topic that still requires proper understanding. Therefore, this study was aimed at evaluating the individual and combined/integrative potential of UV radiation and ultrasonic technologies in the removal of erythromycin- and quinolone-resistant E. coli from domestic effluents using a laboratory experimental-based set-up. The results showed that UV radiation experiment was able to significantly eliminate erythromycin- and quinolone-resistant E. coli from the water to a value of 2 log units. Additionally, US technology was equally able to significantly reduce both the erythromycin- and quinolone-resistant E. coli to 2 log units. However, on combining the two technologies, there was further reduction to 1 log unit, hence, pointing to the need for adopting the integrative approach in water purification for increased wastewater purification efficiencies and improved ecosystem and human health.

scholarly journals Efficiency of the removal of microcystin-LR by UV-radiation and hydrogen peroxide

2019 ◽  
pp. 9-19 ◽  
Author(s):  
Jinna Marcela Loaiza-González ◽  
Melba Cristina León Salazar ◽  
Ainhoa Rubio-Clemente ◽  
Diana Catalina Rodríguez Loaiza ◽  
Gustavo Antonio Peñuela Mesa
Keyword(s):  
Hydrogen Peroxide ◽  
Uv Radiation ◽  
Treatment Time ◽  
Operating Conditions ◽  
Distilled Water ◽  
Photo Degradation ◽  
H2o2 Content ◽  
Uv Irradiance ◽  
Combined Action ◽  
The Individual

Due to the harmful effects associated with the presence of microcystin-LR  (MC-LR) cyanotoxin, photo-degradation assays were performed in natural and distilled water using the combined action of ultraviolet (UV) radiation and hydrogen peroxide (H2O2). The effect of H2O2 content and UV irradiance was evaluated and optimized using a multilevel factorial design in distilled water spiked with 20 μg L-1 MC-LR. The coupled UV/H2O2 system under optimal operating conditions (0.63 mW cm-2 irradiance and 30 mg L-1 H2O2) was more effective than the individual action of UV irradiance or H2O2 content for 30 min of treatment time, since a reduction of 97.78% of MC-LR was achieved. After optimizing the operating conditions, they were applied for natural water, obtaining MC-LR removals similar to those achieved with distilled water (99.59 and 99.73%, respectively), reaching a final MC-LR concentration in both matrices well below the maximum recommended limit established by WHO for MC-LR in drinking water, fixed at 1 μg L-1. 15 mg L-1 of H2O2 were also tested, and although 98.08% of MC-LR elimination was found for a reaction time of 60 min, WHO advisable limit was not surpassed.  The UV/H2O2 process could be considered as an alternative to the conventional processes water facilities are operating with to tackle the problem of fresh water pollution with cyanotoxins, providing the accomplishment of the whole set of water quality standards included in the legislation.

scholarly journals Secretion of Anti-Plasmodium Effector Proteins from a Natural Pantoea agglomerans Isolate by Using PelB and HlyA Secretion Signals

2011 ◽  
Vol 77 (13) ◽  
pp. 4669-4675 ◽  
Author(s):  
Dawn C. Bisi ◽  
David J. Lampe
Keyword(s):  
Control Strategies ◽  
Pectate Lyase ◽  
Erwinia Carotovora ◽  
Individual Characteristics ◽  
Pantoea Agglomerans ◽  
Effector Proteins ◽  
World Health ◽  
Content Type ◽  
E Coli ◽  
The Individual

ABSTRACTThe insect-vectored disease malaria is a major world health problem. New control strategies are needed to supplement the current use of insecticides and medications. A genetic approach can be used to inhibit development of malaria parasites (Plasmodiumspp.) in the mosquito host. We hypothesized thatPantoea agglomerans, a bacterial symbiont ofAnophelesmosquitoes, could be engineered to express and secrete anti-Plasmodiumeffector proteins, a strategy termed paratransgenesis. To this end, plasmids that include thepelBorhlyAsecretion signals from the genes of related species (pectate lyase fromErwinia carotovoraand hemolysin A fromEscherichia coli, respectively) were created and tested for their efficacy in secreting known anti-Plasmodiumeffector proteins (SM1, anti-Pbs21, and PLA2) inP. agglomeransandE. coli.P. agglomeranssuccessfully secreted HlyA fusions of anti-Pbs21 and PLA2, and these strains are under evaluation for anti-Plasmodiumactivity in infected mosquitoes. Varied expression and/or secretion of the effector proteins was observed, suggesting that the individual characteristics of a particular effector may require empirical testing of several secretion signals. Importantly, those strains that secreted efficiently grew as well as wild-type strains under laboratory conditions and, thus, may be expected to be competitive with the native microbiota in the environment of the mosquito midgut.

The seven E. coli ribosomal RNA operon upstream regulatory regions differ in structure and transcription factor binding efficiencies

2005 ◽  
Vol 386 (6) ◽  
pp. 523-534 ◽  
Author(s):  
Annette Hillebrand ◽  
Reinhild Wurm ◽  
Artur Menzel ◽  
Rolf Wagner
Keyword(s):  
Protein Complexes ◽  
Rrna Synthesis ◽  
Dna Fragments ◽  
Promoter Regions ◽  
Regulatory Regions ◽  
E Coli ◽  
Upstream Activating Sequence ◽  
Dna Elements ◽  
The Individual ◽  
Upstream Regulatory Regions

AbstractRibosomal RNAs inE. coliare transcribed from seven operons, which are highly conserved in their organization and sequence. However, the upstream regulatory DNA regions differ considerably, suggesting differences in regulation. We have therefore analyzed the conformation of all seven DNA elements located upstream of the majorE. colirRNA P1 promoters. As judged by temperature-dependent gel electrophoresis with isolated DNA fragments comprising the individual P1 promoters and the complete upstream regulatory regions, all seven rRNA upstream sequences are intrinsically curved. The degree of intrinsic curvature was highest for therrnBandrrnDfragments and less pronounced for therrnAandrrnEoperons. Comparison of the experimentally determined differences in curvature with programs for the prediction of DNA conformation revealed a generally high degree of conformity. Moreover, the analysis showed that the center of curvature is located at about the same position in all fragments. The different upstream regions were analyzed for their capacity to bind the transcription factors FIS and H-NS, which are known as antagonists in the regulation of rRNA synthesis. Gel retardation experiments revealed that both proteins interact with the upstream promoter regions of all seven rDNA fragments, with the affinities of the different DNA fragments for FIS and H-NS and the structure of the resulting complexes deviating considerably. FIS binding was non-cooperative, and at comparable protein concentrations the occupancy of the different DNA fragments varied between two and four binding sites. In contrast, H-NS was shown to bind cooperatively and intermediate states of occupancy could not be resolved for each fragment. The different gel electrophoretic mobilities of the individual DNA/protein complexes indicate variable structures and topologies of the upstream activating sequence regulatory complexes. Our results are highly suggestive of differential regulation of the individual rRNA operons.

Urban wastewater disinfection for agricultural reuse: effect of solar driven AOPs in the inactivation of a multidrug resistant E. coli strain

2015 ◽  
Vol 178 ◽  
pp. 65-73 ◽  
Author(s):  
Giovanna Ferro ◽  
Antonino Fiorentino ◽  
María Castro Alferez ◽  
M. Inmaculada Polo-López ◽  
Luigi Rizzo ◽  
...  
Keyword(s):  
Multidrug Resistant ◽  
Coli Strain ◽  
Urban Wastewater ◽  
E Coli ◽  
Wastewater Disinfection

Loss of an Intimin-Like Protein Encoded on a Uropathogenic E. coli Pathogenicity Island Reduces Inflammation and Affects Interactions with the Urothelium

2021 ◽  
Author(s):  
Allyson E. Shea ◽  
Jolie A. Stocki ◽  
Stephanie D. Himpsl ◽  
Sara N. Smith ◽  
Harry L. T. Mobley
Keyword(s):  
Ex Vivo ◽  
Cell Adherence ◽  
Upec Strain ◽  
E Coli ◽  
Bladder Cell ◽  
Bladder Cells ◽  
Strain Cft073 ◽  
The Individual ◽  
Tract Infections

Uropathogenic Escherichia coli (UPEC) causes the majority of uncomplicated urinary tract infections (UTI), which affect nearly half of women worldwide. Many UPEC strains encode an annotated intimin-like adhesin ( ila ) locus in their genome related to a well-characterized virulence factor in diarrheagenic E. coli pathotypes. Its role in UPEC uropathogenesis, however, remains unknown. In prototype UPEC strain CFT073, there is an ila locus that encodes three predicted intimin-like genes sinH , sinI , and ratA . We used in silico approaches to determine the phylogeny and genomic distribution of this locus among uropathogens. We found that the currently annotated intimin-encoding proteins in CFT073 are more closely related to invasin proteins found in Salmonella . Deletion of the individual sinH , sinI , and ratA genes did not result in measurable effects on growth, biofilm formation, or motility in vitro . On average, sinH was more highly expressed in clinical strains during active human UTI than in human urine ex vivo . Unexpectedly, we found that strains lacking this ila locus had increased adherence to bladder cells in vitro , coupled with a decrease in bladder cell invasion and death. The sinH mutant displayed a significant fitness defect in the murine model of ascending UTI including reduced inflammation in the bladder. These data confirmed an inhibitory role in bladder cell adherence to facilitate invasion and inflammation; therefore, the ila locus should be termed invasin-like, rather than intimin-like. Collectively, our data suggest that loss of this locus mediates measurable interactions with bladder cells in vitro and contributes to fitness during UTI.

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