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Behavior of Antibiotic-Resistant Fecal Coliforms in the Stream of a Sewage Treatment Plant in Tokyo
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作者 Naoto Urano Masahiko Okai +4 位作者 Yusuke Tashiro Azusa Takeuchi Rintaro Endo Masami Ishida Masachika Takashio 《Advances in Microbiology》 2020年第7期318-330,共13页
<span style="font-family:Verdana;">We are confronting a new threat in the prevalence of antibiotic-resistant bacteria followed by epidemic spread in aquatic environments in metropolitan areas because d... <span style="font-family:Verdana;">We are confronting a new threat in the prevalence of antibiotic-resistant bacteria followed by epidemic spread in aquatic environments in metropolitan areas because damage from river floods is increasing remarkably in Japan due to global extreme weather. The sewer penetration rate is about 100% in Tokyo and reclaimed water from sewage treatment plants accounts for over 50% of all water in both the down- and mid-stream areas of local rivers. The water quality of these rivers, which contain microflora, seems to be seriously affected by reclaimed water. In this study, we collected water samples on July 17, 2018 and examined the behavior of antibiotic-resistant fecal coliforms in the stream of a sewage treatment plant in Tokyo. Extended-spectrum </span><i><span style="font-family:Verdana;">β</span></i><span style="font-family:Verdana;">-lactamase (ESBL)</span><span style="font-family:Verdana;">-producing fecal coliforms with encoding genes were found;the CTX-M-1, CTX-M-9, TEM, and SHV groups were found to have survived in the final effluent to the river after sterilization with sodium hypochlorite. 展开更多
关键词 Antibiotic-Resistant Bacteria (ARB) Extended-Spectrum β-Lactamase (ESBL) fecal coliforms Sewage Treatment Plant Reclaimed Water
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Performance of a Horizontal Flow Constructed Reed Bed Filter for Municipal Wastewater Treatment: The Case Study of the Prototype Installed at Gaston Berger University, Saint-Louis, Senegal
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作者 Abdou Khafor Ndiaye Falilou Coundoul +2 位作者 Abdoulaye Deme Antonina Torrens Armengol Abdoulaye Senghor 《Natural Resources》 2024年第1期1-16,共16页
In Saint-Louis, Senegal, a constructed wetland with horizontal flow reed beds (FHa and FHb) has demonstrated significant efficacy in treating municipal wastewater. Analyzing various treatment stages, the system showed... In Saint-Louis, Senegal, a constructed wetland with horizontal flow reed beds (FHa and FHb) has demonstrated significant efficacy in treating municipal wastewater. Analyzing various treatment stages, the system showed only a slight temperature variation, from an influent average of 26.3°C to an effluent of 24.7°C. Electrical conductivity decreased from 1331 mS/cm to 974.5 mS/cm post-primary treatment, with suspended solids (SS) dramatically reduced from 718.9 mg/L to 5.7 mg/L in the final effluent. Biochemical oxygen demand (BOD5) and chemical oxygen demand (COD) saw a notable decrease, from initial levels of 655.6 mg/L and 1240 mg/L to 2.3 mg/L and 71.3 mg/L, respectively. Nitrogenous compounds (N-TN) and phosphates () also decreased significantly, indicating the system’s nutrient removal capacity. Microbiological analysis revealed a reduction in fecal coliforms from 7.5 Ulog/100ml to 1.8 Ulog/100ml and a complete elimination of helminth eggs. The presence of Phragmites and Typha was instrumental in enhancing these reductions. The system’s compliance with the Senegalese standards for disposal into natural environments, WHO recommendations for unrestricted water reuse in irrigation, and the European legislation for water reuse was established. The effluent quality met the stringent criteria for various classes of agricultural reuse, illustrating the system’s potential for sustainable water management. This wetland model presents a robust solution for water-stressed regions, ensuring environmental protection while supporting agricultural needs. The study calls for ongoing research to further refine the system for optimal, reliable wastewater treatment and water resource sustainability. 展开更多
关键词 Constructed Wetlands Horizontal Flow Reed Beds Wastewater Treatment Phragmites and Typha Plants Physicochemical Pollutant Removal Microbiological Indicators fecal coliforms and Helminth Eggs Water Quality Improvement Senegal Water Reuse Standards Sustainable Water Management Agricultural Irrigation Reuse Nutrient Removal Efficiency Environmental Engineering Ecological Sanitation Systems
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Zinc phosphate-based nanoparticles as alternatives to zinc oxide in diet of weaned piglets 被引量:1
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作者 Silvia Kociova Kristyna Dolezelikova +14 位作者 Pavel Horky Sylvie Skalickova Daria Baholet Lucie Bozdechova Eva Vaclavkova Jaroslava Belkova Pavel Nevrkla Jiri Skladanka Tomas Do Ondrej Zitka Yazan Haddad Pavel Kopel Ludek Zurek Vojtech Adam Kristyna Smerkova 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2020年第4期1147-1162,共16页
Background: The high doses of zinc oxide(Zn O) administered orally to piglets for the prevention of diarrhea and increase of growth rate can contaminate pig farms and the surrounding environment. Therefore, there is a... Background: The high doses of zinc oxide(Zn O) administered orally to piglets for the prevention of diarrhea and increase of growth rate can contaminate pig farms and the surrounding environment. Therefore, there is a need to find a replacement of high doses of dietary Zn O with an equally effective alternative. In the present study, the effect of two formulations of zinc phosphate-based nanoparticles(Zn A and Zn C NPs) on growth performance,intestinal microbiota, antioxidant status, and intestinal and liver morphology was evaluated. A total of 100 weaned piglets were randomly divided into 10 equal groups with the base diet(control) or the base diet supplemented with Zn A, Zn C, or Zn O at concentrations 500, 1000, and 2000 mg Zn per kilogram of diet. Supplements were given to animals for 10 days. Fecal samples were collected on day 0, 5, 10 and 20. At the end of the treatment(day 10),three piglets from each group were sacrificed and analyzed.Results: Comparing to that of control, the significantly higher piglet weight gain was observed in all piglet groups fed with Zn A(P < 0.05). Differences in the total aerobic bacteria and coliform counts in piglet feces after NPs supplementation compared to that of control and Zn O groups were also found(P < 0.05). The majority of aerobic culturable bacteria from the feces represented Escherichia(28.57–47.62%), Enterococcus(3.85–35.71%), and Streptococcus(3.70–42.31%) spp. A total of 542 Escherichia coli isolates were screened for the virulence genes STa,STb, Stx2, F4, and F18. The substantial occurrence of E. coli virulence factors was found on day 5, mainly in fimbrillary antigen and thermostable toxins, except for piglets fed by Zn C. Zn treatment decreased Zn blood levels in piglets fed with Zn O and Zn A(500 mg/kg) and increased in Zn C(2000 mg/kg) compared to that of control(P < 0.05). The antioxidant status of piglets was affected only by Zn A. While some changes in the liver and the intestinal morphology of piglets with NPs were observed, none were serious as reflected by the normal health status and increased weigh gain performance.Conclusions: Our results indicate that Zn A NPs have a positive effect on the piglet growth performance even at the lowest concentration. The prevalence of E. coli virulence factors was lowest in pigs supplemented with Zn C.Zinc phosphate-based nanoparticles may be an effective alternative to Zn O. 展开更多
关键词 Antioxidant status DIET E.coli STa STB Stx2 F4 F18 fecal coliforms MICROBIOTA
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The Bacterial Load of Hospital Discharges(Sidi Kacem,Morocco)
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作者 Sanae Sadek F.Benel Harkati +7 位作者 K.Elkharrim F.Jeddi I.Rhiate Moufouad M.Elmarkhi A.Khadmaoui S.Mouden Z.Dakir D.Belghyti 《Advances in Microbiology》 2013年第7期511-514,共4页
Fecal microorganisms, which are indicators or pathogens, have an optimum growth in the specific conditions of the internal environment animal or human. Therefore, when issued by a host, they result in sudden and drast... Fecal microorganisms, which are indicators or pathogens, have an optimum growth in the specific conditions of the internal environment animal or human. Therefore, when issued by a host, they result in sudden and drastic changes in the environment. This study aims at bacteriological characterization of the effluent from the provincial hospital in Sidi Kacem. And it shows that the effluent from the hospital contributing to non-regulatory standards ultimately reaches the environment (river wadi floor, animal, vegetable...). The results of bacteriological analyses (Total Coliforms, Fecal Coliforms) about sewage from the provincial hospital depending on the day of rest and work in the city of Sidi Kacem are presented with means respectively 557 × 104 and 328 × 104 in the rest and working days 555 × 104, 342 × 104 and the much higher maximum working days from the day of rest are 64 × 105 and 42 × 105. The results obtained show that the rate of bacteria (CT-CF) exceeds standards recommended by CNS (1994) and WHO (1996, 1997). These results have adverse effects on human life, animal, environment and ecosystem in general. 展开更多
关键词 BACTERIOLOGY Total coliforms fecal coliforms HOSPITAL Sidi Kacem Morocco
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Drinking Water Quality in the Sagarmatha National Park, Nepal 被引量:1
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作者 Kirsten Nicholson Emily Hayes +2 位作者 Klaus Neumann Carolyn Dowling Subodh Sharma 《Journal of Geoscience and Environment Protection》 2016年第4期43-53,共11页
In 2014 we began the first systematic study of water quality, specifically fecal contamination of drinking water in the Khumbu Valley, Sagarmatha National Park (SNP, Mt. Everest region), Nepal. Our goal was to identif... In 2014 we began the first systematic study of water quality, specifically fecal contamination of drinking water in the Khumbu Valley, Sagarmatha National Park (SNP, Mt. Everest region), Nepal. Our goal was to identify coliform bacteria and E. coli in drinking water and groundwater-fed springs to generate a data set that will function as a base for potable water supplies and further monitoring. Sampling occurred in May (pre-monsoon summer) and early November (post-monsoon early winter) 2014. Sample sites were selected based on proximity to villages and primary use as a drinking water source. Overall, the data presented a predictable correlation between fecal contamination and both elevation and increasing population/tourist traffic. Drinking water within the study area met current World Health Organization drinking water standards for the physical properties of temperature (2.8°C - 13°C), pH (5.27 - 7.24), conductivity (14.5 - 133 mS) and TDS (7.24 - 65.5 ppm). Samples from the more populated, lower altitude areas had higher levels of E. coli. Samples collected and analyzed in May (pre-monsoon summer) had a higher level of E. coli and coliform bacteria than samples collected in November (post-monsoon early winter) suggesting a seasonal dependence overlaid on the population signature. Surface water typically had higher E. coli values than groundwater-fed springs. Temperature, total dissolved solids and conductivity generally decreased with increasing elevation, whereas pH increased with increasing elevation. There appears to be significant presence of fecal contamination of water sources due to a combination of tourism, elevation and seasons. 展开更多
关键词 fecal Coliform E. coli Mt. Everest Drinking Water
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Evaluating Drinking Water Treatment Methods in the Njala University and Neighboring Mokonde Communities in Southern Sierra Leone 被引量:1
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作者 Abdulai Barrie Abubakarr Swaray +1 位作者 Mariatu Barrie Joe Beah 《Natural Resources》 2021年第8期257-270,共14页
<span style="font-family:Verdana;">Rural communities in sub</span><span style="font-family:Verdana;"><span style="font-family:Verdana;">-</span></span>... <span style="font-family:Verdana;">Rural communities in sub</span><span style="font-family:Verdana;"><span style="font-family:Verdana;">-</span></span><span style="font-family:Verdana;">Saharan Africa (SSA) are always faced with the challenge of securing safe water for beneficial uses. Most communities lack a centralized water supply system and, thus, each residence utilizes the treatment method that they can afford. This study evaluated three treatment methods for drinking water in the Njala University and Mokonde communities in southern Sierra Leone. In the perceived natural treatment, residents in the Mokonde community believe that groundwater has been purified by the soil media and, hence, does not require further treatment. In the conventional treatment, the Njala University Water Works use sand filtration and chlorine disinfection to treat water from the Taia River. The third treatment method, first flush diversion, was introduced by Njala University researchers in 2014. We studied the populations of coliform bacteria and </span><i><span style="font-family:Verdana;">E. coli</span></i><span style="font-family:Verdana;"> in untreated and treated water samples to determine if each of the treatment methods supported the beneficial use of drinking. This study concludes that the natural filtration does not remove pathogens in the well water. Even though the first flush and conventional treatments were efficient in reducing microbial populations in the water, the World Health Organization’s 100% removal guideline was not achieved most of the time. Therefore, all three treatment methods did not support the beneficial use of drinking. Further treatment was needed to render the water potable. 展开更多
关键词 Perceived Natural Treatment Conventional Treatment First Flush Diversion Total Coliform fecal Coliform E. coli Beneficial Use
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Water Quality Assessment of Padada Watershed, Davao del Sur, Philippines
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作者 Nympha E.Branzuela Rhea Lou R.Germo +1 位作者 Charlyn T.Gorgonio Wernher T.Branzuela 《Journal of Environmental Science and Engineering(B)》 2022年第2期31-36,共6页
Water and its importance cannot be understated.Its greatest value lies in its ability and capacity to provide biological and environmental services.Water quality is an essential parameter to be studied when the overal... Water and its importance cannot be understated.Its greatest value lies in its ability and capacity to provide biological and environmental services.Water quality is an essential parameter to be studied when the overall focus is sustainable development keeping mankind at a focal point.The study assessed the water quality and its suitability for drinking purposes in most areas of Padada Watershed.In this study,nine identified sampling points were analyzed for different physico-chemical parameters such as turbidity,BOD(Biological Oxygen Demand),TSS(Total Solid Suspended),fecal coliform,pH,temperature,DO(Dissolved Oxygen),and SC(Specific Conductivity).Results found turbidity range from 0.74-19.7 NTU;BOD range from 0.04-2.2 mg/L;TSS range from 1-411 mg/L;fecal coliform range from<1.8-160,000 MPN/100mL.The temperature value ranges from 24.8-31.9°C;pH value ranges from 7.05-7.92;SC ranges from 119.7-551μS/cm while DO range from 4.87-8.14 mg/L.Moreover,the results revealed that most sampling sites exceeded the permissible limits.The highest concentration of fecal coliform indicates contamination which may cause possible human health infection.Thus,the water of Padada River Watershed is not potable for drinking and it is recommended to take beneficial steps to prevent adverse health effects to the community. 展开更多
关键词 Water quality PHYSICO-CHEMICAL fecal coliform TURBIDITY Padada Watershed
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