Membrane Filtration Technique Research Articles

Physicochemical characteristics and antibiotic resistance patterns of enteric bacteria isolated from harvested rainwater (HRW) in Oraukwu, Anambra State, Nigeria

infections temperature, colour, turbidity, DO, TDS, TSS, alkalinity, hardness, chloride, and some heavy metals of the water samples were examined using APHA method. Bacteriological analyses were performed using the membrane filtration technique. Colonies formed were counted and expressed in CFU/100mL. Enteric bacteria were enumerated and characterized by their morphological characteristics and biochemical tests. Axenic cultures of the isolates were further subjected to antimicrobial susceptibility testing (AST) using the modified Kirby-Bauer disc diffusion method, based on the guidelines by CLSI. Results revealed that physicochemical parameters and some heavy metals were within acceptable limits, except for Fe (0.01-0.72 mg/L) and Pb (0.01-0.25 mg/L). Total bacterial counts ranged from 1.2×104 to 6.8×104 CFU/100mL, indicating high contamination. Morphological characteristics revealed twelve (12) isolates of enteric bacteria, comprising Escherichia coli (41.67%), Salmonella sp. (33.33%) and Shigella sp. (25%). All the isolates exhibited 100% resistant to augmentin and tetracycline, but showed varying degrees of susceptibilities; E. coli to levofloxacin (60%), Salmonella sp. to ertapenem, imipenem, levofloxacin and nalidixic acid (100%), and Shigella sp. to ceftriaxone and ertapenem (100%). ‘First flush’ diverters are recommended to be installed within the water collecting system, in order to divert runoff from the rooftop after a period of no rainfall. Antibiotics which the isolates were susceptible to are recommended for the treatment of infections caused by these pathogens.

Strategies for Removing Endocrine Disrupting Chemicals (EDCs) from Wastewater.

Endocrine-disrupting drugs, also called endocrine disruptors or micropollutants, cause serious environmental and public health problems due to their ability to disrupt the endocrine functions of organisms and humans, even at low concentrations. This report provides a summary of current removal techniques, such as activated sludge processes, membrane filtration, adsorption, and membrane bioreactor techniques for endocrine-disrupting chemicals, including their efficiency, limitations, and practical implementation. This review evaluates these methods by considering their treatment efficiency, costs, and environmental impact. To curb this menace, several developed countries have distinct strategies, such as physical remediation techniques, biological processes, phytoremediation, and chemical processes to remove endocrine disruptors. In developing nations, most conventional wastewater treatment plants do not even monitor those contaminants due to the low biodegradability and high complexity of such compounds. Hence, in this review work, potential endocrine-disrupting chemicals, their impacts, mechanisms of action, consequences for human health, and bio-mitigation strategies reported so far have been discussed in the context of the relevant literature.

Bacteriological Quality of Borehole Water in Gusau Metropolis

Study’s Novelty/Excerpt This study is novel as it presents the first extensive bacteriological assessment of borehole water quality in Gusau metropolis, highlighting significant public health concerns. By analyzing multiple contamination indicators including total bacterial load, total coliform, fecal coliform, and Salmonella-Shigella counts, this research provides a detailed and comprehensive evaluation of water safety. Furthermore, the identification of specific bacterial contaminants such as Escherichia coli, Salmonella typhi, and Shigella spp., combined with the finding that contamination levels exceed WHO standards, underscores the urgent need for water treatment interventions to prevent waterborne diseases. Full Abstract Microbes are ubiquitous and are known to contaminate materials, including food and water. We examined the bacteriological quality of borehole water in Gusau metropolis to determine its potability. Triplicate samples were collected from fifteen (15) different boreholes and analyzed. The total bacterial load, total coliform, fecal coliform, and Salmonella-Shigella count were determined using the membrane filtration technique. The average counts were as follows: total bacteria ranged from 6×10^1 cfu/ml to 39×10^1 cfu/ml, total coliform count from 3×10^1 cfu/ml to 65×10^1 cfu/ml, fecal coliform count from 1×10^0 cfu/ml to 4×10^0 cfu/ml, and Salmonella-Shigella count from 0 cfu/ml to 4×10^0 cfu/ml. The isolated organisms were identified as Escherichia coli, Salmonella typhi, and Shigella spp. The predominant bacterial isolate was Escherichia coli. Our study indicated that the bacteriological quality exceeded the World Health Organization (WHO) allowable limits of 0 cfu/100ml for total bacterial load, total coliform count, fecal coliform count, and Salmonella-Shigella count due to the underground aquifers. Therefore, we recommend that borehole water sources be adequately treated before consumption to reduce the risk of waterborne diseases.

Valorisation of Tannery Waste to Recover Chromium with a View to Reusing It in Industrial Practise.

This paper presents the basic assumptions of the concept of a new technology for the valorisation of chromium tannery waste. It assumes the use of an integrated system of the thermal pressure hydrolysis process and membrane filtration techniques for the recovery of chromium compounds and the use of a separated organic matter during anaerobic fermentation. According to the assumptions of the developed technological concept, at the first stage, the crushed mixture of chromium tannery waste is decomposed in the process of thermal pressure hydrolysis using appropriate process conditions in an alkaline environment. Then, the liquid product of this process (the so-called hydrolysate) is processed using centrifugal force separation and ultrafiltration. Such activities enable the recovery of chromium compounds for rawhide currying and concentration of organic matter (fats, proteins) with energy potential. Research carried out under conditions similar to real operating conditions proved that chromium compounds recovered from waste can be successfully used in the processing of cowhides intended for the production of footwear. The industrial implementation of the developed technology for valorising chromium tannery waste would enable the transition from a linear to a circular economy.

Multivariate statistical methods for analysis of physicochemical and microbiological parameters of well water from the village M’Pody

The pollution of surface water and groundwater is a real public health problem that is currently receiving particular attention throughout the world. The use of water for food or hygiene purposes requires excellent physicochemical and microbiological quality. Well water is used for many purposes by the inhabitants of M’pody, a village in the Anyama district of Côte d’Ivoire. In this village, an epidemic of diarrhoea was detected in January 2020. This epidemic claimed sixty-nine (69) victims. This study aims to evaluate well water quality controls using the methods of principal component analysis (PCA), correspondence factorial analysis (CFA), analysis of variance (ANOVA) and self-organizing map (SOM) algorithm. The parameters studied were, turbidity (Tur), conductivity (Cond), hydrogen potential (pH), temperature (T), nitrate (NO3-\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$NO_{3^{-}}$$\\end{document}), nitrite (NO2-\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$NO_{2^{-}}$$\\end{document}), ammonium (NH4+\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$NH_{4^{+}}$$\\end{document}), phosphates (PO43-\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$PO_{4}^{3^{-}}$$\\end{document}), chlorides (Cl-)\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$(Cl^{-})$$\\end{document}, total hydrotimetric degree (DHT), sulfates (SO42-\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$SO_{4}^{2^{-}}$$\\end{document}), bicarbonate (HCO3-\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$HCO_{3^{-}}$$\\end{document}), total alkalinity contents (TAC), escherichia coli (E.coli), thermotolerant coliforms (CTH) and enterococcus faecalis (E.faecalis). Data were collected from seventy-two (72) wells in the village during four campaigns in 2020. Physicochemical parameters were determined by electrochemical and spectrophotometric methods. Microbiological analysis was carried out using membrane filtration technique. Descriptive statistics revealed that Tur, Cond, pH and T parameters did not meet world health organization (WHO, 2017) standards. However, the parameters NO3-\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$NO_{3^{-}}$$\\end{document}, NO2-\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$NO_{2^{-}}$$\\end{document}, NH4+\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$NH_{4^{+}}$$\\end{document}, PO43-\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$PO_{4}^{3^{-}}$$\\end{document}, Cl-\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$Cl^{-}$$\\end{document}, DHT, TAC, SO42-\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$SO_{4}^{2^{-}}$$\\end{document} and HCO3-\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$HCO_{3^{-}}$$\\end{document} comply with WHO standards. The results of bacteriological analyzes confirm the presence in very significant numbers of indicators of faecal contamination (CTH, E.coli and E.faecalis) in all wells. The logical explanations for faecal pollution would come from the infiltration of septic tanks located near the wells and the run-off of waste water carrying human and animal faecal matter. The diarrhea epidemic would therefore be caused by the consumption of this polluted water. PCA, FCA and hierarchical cluster analysis (HCA) were jointly employed to identify the structure of wells and deduce the principal factors controlling the parameters of these well waters. ANOVA revealed the effect of human-induced activities as the main factors influencing the physicochemical and microbiological parameters of the studied well waters. Further studies should focus on multivariate statistical techniques for effective forecasting and monitoring of emerging pollution for improved water quality.

Capillary Force-Driven Quantitative Plasma Separation Method for Application of Whole Blood Detection Microfluidic Chip.

Separating plasma or serum from blood is essential for precise testing. However, extracting precise plasma quantities outside the laboratory poses challenges. A recent study has introduced a capillary force-driven membrane filtration technique to accurately separate small plasma volumes. This method efficiently isolates 100-200 μL of pure human whole blood with a 48% hematocrit, resulting in 5-30 μL of plasma with less than a 10% margin of error. The entire process is completed within 20 min, offering a simple and cost-effective approach to blood separation. This study has successfully addressed the bottleneck in self-service POCT, ensuring testing accuracy. This innovative method shows promise for clinical diagnostics and point-of-care testing.

Quantitative microbial risk assessment of gastrointestinal illness due to recreational exposure to E. coli and enterococci on the southern coasts of the Caspian Sea

BackgroundGastrointestinal illness refers to a broad range of diseases that affect the digestive system, including infections caused by bacteria, viruses, and parasites. Quantitative Microbial Risk Assessment (QMRA) is a powerful tool used to evaluate the risks associated with microbial pathogens in various environments. The main objective of this study was to conduct a quantitative assessment of gastrointestinal illnesses that occur as a result of exposure to E. coli and enterococci during recreational activities on the southern coasts of the Caspian Sea. MethodsSamples were collected from the recreational beaches along the border line of the Caspian Sea. The samples were analyzed for the presence and enumeration of E. coli and enterococci using the microplate method and membrane filtration techniques. Then, the annual and daily infection risks were computed using the Monte Carlo simulation approach. ResultsThe results revealed that the risk of daily and annual infections on the coasts of Babolsar was higher than that on the coasts of Sari. Also, in the recreational waters of these beaches, the risk of infection by enterococci was higher than that posed by E. coli. In Babolsar, the average annual infection risk caused by E. coli and enterococci was 0.365 and 1 for children and 0.181 and 0.986 for adults. Also, in Sari, the average annual infection risk caused by E. coli and enterococci was 0.060 and 0.908 for children and 0.027 and 0.815 for adults. In addition, children were more likely than adults to become infected. ConclusionIn light of the study's findings, due to the entry of untreated urban wastewater into the southern part of the Caspian Sea (northern Iran) and the high risk of infectious diseases for children, more control and health measures are necessary for children's swimming.

Quantitative Analysis of Genomic DNA Degradation of E. coli Using Automated Gel Electrophoresis under Various Levels of Microwave Exposure.

The problem that this study addresses is to understand how microwave radiation is able to degrade genomic DNA of E. coli. In addition, a comparative study was made to evaluate the suitability of a high-throughput automated electrophoresis platform for quantifying the DNA degradation under microwave radiation. Overall, this study investigated the genomic DNA degradation of E. coli under microwave radiation using automated gel electrophoresis. To examine the viable organisms and degradation of genomic DNA under microwave exposure, we used three methods: (1) post-microwave exposure, where E. coli was enumerated using modified mTEC agar method using membrane filtration technique; (2) extracted genomic DNA of microwaved sample was quantified using the Qubit method; and (3) automated gel electrophoresis, the TapeStation 4200, was used to examine the bands of extracted DNA of microwaved samples. In addition, to examine the impacts of microwaves, E. coli colonies were isolated from a fecal sample (dairy cow manure), these colonies were grown overnight to prepare fresh E. coli culture, and this culture was exposed to microwave radiation for three durations: (1) 2 min; (2) 5 min; and (3) 8 min. In general, Qubit values (ng/µL) were proportional to the results of automated gel electrophoresis, TapeStation 4200, DNA integrity numbers (DINs). Samples from exposure studies (2 min, 5 min, and 8 min) showed no viable E. coli. Initial E. coli levels (at 0 min microwave exposure) were 5 × 108 CFU/mL, and the E. coli level was reduced to a non-detectable level within 2 min of microwave exposure. The relationships between Qubit and TapeStation measurements was linear, except for when the DNA level was lower than 2 ng/µL. In 8 min of microwave exposure, E. coli DNA integrity was reduced by 61.7%, and DNA concentration was reduced by 81.6%. The overall conclusion of this study is that microwave radiation had a significant impact on the genomic DNA of E. coli, and prolonged exposure of E. coli to microwaves can thus lead to a loss of genomic DNA integrity and DNA concentrations.

Assessment of Drinking Water Quality from Source to Household Storage Containers in Kachisi town, West Shewa, Ethiopia

A wide range of human and natural processes affect the quality of fresh waters and diseases related to contamination of drinking water constitute a major burden on human health. Thus, this study was conducted to assess the quality of drinking water supplied to Kachisi town using selected physicochemical and bacteriological parameters. A total of 60 water samples in triplicate were collected from boreholes, water reservoirs, household taps and storage containers in the households between October, 2019 and February, 2020. The physiochemical parameters were measured using HACH HQ440d multi meter and portable digital spectrophotometer (DR/6000) according to HACH instruction and bacteriological parameters were analyzed using the membrane filtration technique. The study results indicated that temperature and pH of the water samples were in the range of 18.77 0C and 21.4 0C, and 7.05 and 7.73, respectively. Total dissolved solids fell between 93 mg/l and116 mg/l while electrical conductivity records ranged between 185µS/cm and 232 µS/cm. The concentrations of Iron, nitrate and phosphate were in the range between 0.01-0.26 mg/l, 2.20-5.72 mg/l and 0.12-0.76 mg/l, respectively. Total Coliforms loadalso varied from 1CFU/100ml to 2CFU/100ml in samples collected from boreholes and reservoirs, from 1CFU/100ml to 12CFU/100ml in tap water samples and from 6CFU/100ml to 22CFU/100ml in samples from storage containers in the households. Fecal Coliform was negative in the water samples collected from boreholes, reservoirs and household taps while it was detected in 25% of the samples collected from household storage containers in the rangeof 3CFU/100ml to 5CFU/100ml. The detection of Total Coliforms in all water samples and Faecal Coliforms in some of the household containers samples might be attributed to absence of disinfection, lack of regular supervision of the system, poor water management and lack of safe water storage and handling practices.

Quality Assessment of a University-Based Packaged Water Factory

This study carried out an overall assessment of the water factory of Osun State University to check compliance with Good Manufacturing Practices. The study involved the assessment of the water factory facilities and the performance evaluation of the treatment units. Water samples were taken from the source water to the final treatment units and were analysed for some physicochemical and microbiology characteristics. The pH, TDS, and EC were analysed on the site out using the Hanna brand hand-held pH meter, total hardness, calcium, and magnesium were analysed using the titrimetric method, sulphate and nitrate were analysed using turbidimetric and brucine methods respectively while heavy metals were analysed using Atomic Absorption Spectrophotometry (AAS). Microbiological characteristic was carried out using the Membrane filtration technique. The physico-chemical characteristics of the source water are 174, 128.8,57.2,6.31,5.77, 55.08, 1.84 0.017,0.115 mg/L while that of the permeate are 138.8, 98.8, 52.7, 6.4, 5.45, 15.57,1.42, 0.016, and 0.114 mg/L for Total Hardness, Ca2+, Mg2+, NO3--, SO42- TDS, K+, Pb2+, and Fe2+, respectively. The pH for the permeate is 6.32, the coliform concentration is between 0-1×105 CFU and the salt water rejection is 87.17%. The water factory complied well with good manufacturing and hygiene practices and the treatment units are functional. There is a need to equip the existing laboratory, perform microbiological analysis routinely and control the pH values.

Detection and quantitative microbial risk assessment of pathogenic Vibrio cholerae in a river used for drinking, domestic, fresh produce irrigation and recreational purposes

Cholera infection results from the ingestion of water or food contaminated with toxigenic Vibrio cholerae. This study evaluated the occurrence of toxigenic V. cholerae in Asata River, Enugu Metropolis, Nigeria, and estimated V. cholerae infection risks from use of the River water for drinking, domestic and recreational purposes. Vibrio was detected and quantified using membrane filtration technique and thiosulfate–citrate–bile salts–sucrose agar. Isolates were screened by PCR, using specific primers targeting the internal transcribed spacer (its) region between 16 and 23S rRNA and the cholera toxin (ctx) gene. Sequenced 16SrRNA gene amplicons of two selected isolates were used for phylogenetic analysis. Quantitative microbial risk assessment (QMRA) was conducted using the β-Poisson dose–response model. About 81% (58/72) of Asata River samples recorded Vibrio counts above 1.0 ×\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\ imes$$\\end{document} 103 cfu/100 mL. Of the fifty Vibrio isolates screened, its was detected in 54% (27/50), out of which 74% (20/27) had the ctx gene of toxigenic V. cholerae. Evolutionary relatedness of the sequenced isolates to V. cholerae was revealed. The estimated risks of cholera infection in persons exposed to untreated Asata River water were above 0.5 for all the exposure scenarios, for both the rainy and dry seasons. The risks were highest (~ 0.9) for exposure via drinking water and annual risk of infection was deduced to have a probability of 1.0. Therefore, dependence on the untreated Asata River water for drinking, recreational, domestic and irrigation purposes may present a potential public health risk of cholera outbreak. We recommend increased monitoring and surveillance of River water for Vibrio abundance and that Asata River be protected from further degradation.

Effect of some physicochemical parameters on the decay rate of enteric bacteria isolated from River Owena, Nigeria

The significance of water in public health cannot be overemphasized. In Nigeria, many people living along the courses of water bodies still source and drink from the rivers and streams. There is, therefore, the need to determine the load of contamination and effect of pH and salinity on the decay rate of enteric bacteria in water samples from River Owena, Owena, Nigeria, in order to develop adequate water quality management. Water samples from River Owena were collected from three sampling points (inflow, middle course and the outflow) along the River Owena, Nigeria. The load of enteric bacteria in the water samples was enumerated using membrane filtration technique. The physicochemical parameters of the water samples were determined using standard methods. The incidence and prevalence of gastroenteritis in the community around River Owena was determined using a structured questionnaire. Microcosm studies were used to determine the decay rate of enteric bacteria at varying salinity and pH. Canonical correlation analysis was used to describe the relationship between the load of enteric bacteria and the incidence and prevalence of gastroenteritis in the community around River Owena. The incidence and prevalence of gastroenteritis in the community around River Owena were estimated to be 0.75 and 0.51, respectively. Escherichia coli had positive relationships with incidence (r = 0.76) and prevalence (r = 0.65). Similarly, faecal coliforms had positive relationships with incidence (r = 0.82) and prevalence of gastroenteritis (r = 0.67), while enterococci showed positive relationship with incidence (r = 0.59) and prevalence of gastroenteritis (r = 0.87). Increase in pH and salinity increased the decay rate of enteric bacteria thereby reducing the growth of enteric bacteria, the optimum pH for the growth and survival of enteric bacteria ranged between pH 5.0 and pH 7.0. The optimum salinity for the growth of enteric bacteria isolated in water samples from River Owena ranged between 10 and 50% salinity. Findings revealed high levels of faecal contamination at the different representative monitoring points on River Owena, pH and salinity influenced the load and decay rate of enteric bacteria in water from River Owena.

Microorganisms in water for daily consumption on Luis Vargas Torres Island in the city of Esmeraldas

Introduction: microbiological analysis of water involves evaluating water quality in terms of identification and presence of pathogenic and non-pathogenic agents to ensure that the water is safe for daily human use and consumption. Objetive: to identify the microorganisms in the water for daily consumption in the families living on Luis Vargas Torres Island in the city and province of Esmeraldas. Method: a cross-sectional quantitative analytical study was carried out on 121 water samples from reservoirs and taps selected through simple random probability sampling using sterile Whirl-Pak® bags with sodium thiosulfate for sample collection. In the laboratory analysis, the membrane filtration technique with a uniform diameter of 0.45 μm was used to obtain the bacteria on the surface of the membrane filter, which were inoculated in differential culture media for fungi and bacteria and in all cases the count was performed by the Most Probable Number (MPN) method. The final data were consolidated in an Excel table for the final elaboration of frequency tables and graphs. Results: of the total samples analyzed, E. coli was identified in 20 %, Salmonella spp. 10 % and Shigella spp. 4 %; and total coliforms such as Citrobacter spp. and Klebsiella spp. present in 8 %, Enterobacter spp. in 6 % and Pseudomona spp. 2 % indicators of fecal contamination and fungi such as Mucor spp. represents 2 %, Penicilum spp. and Aspergillus fumigatus 3 % and Alternaria alternata and Absidia spp. 4 % and 5 % respectively. Conclusions: research on microbiological water contamination in unplanned urban communities reveals the presence of pathogens and drinking water quality indicators, such as fungi, total coliforms, and species-specific species such as E. coli, Salmonella spp., and Shigella spp., indicating fecal contamination. These findings highlight the urgent need for sanitation and hygiene interventions in this community to effectively manage water quality and health risks

Bacterias resistente a los antibióticos en aguas mineromedicinales “Santagua Chachimbiro”, Ecuador

Bacterial biodiversity in mineral medicinal waters and the antibiotic resistance profiles, is a developing topic in Ecuador. The objective of the work was to know the bacterial microbiota and its resistance profiles to antibiotics of the mineral medicinal waters of the Santagua Chachimbiro spa, located in the Province of Imbabura-Ecuador. 16 water samples were collected. The isolation of the bacterial species was carried out by the membrane filtration technique, using different types of culture media. The identification was carried out according to the schemes proposed by MacFaddin (2003), complemented with the tests of the Microgen galleries. The antibiotic resistance profile was determined by the Kirby and Bauer (1966) plate diffusion method. 85 strains were isolate of which 61% were Gram negative and 39% Gram positive. The main species identified were Aeromonas caviae, Aeromonas eucrenophila, Aeromonas hydrophila, Aeromonas media, Aeromonas salmonicida, Aeromonas schubertii, Bacillus subtilis, Bacillus mycoides, Bacillus spp, Burkholderia cepacia, Citrobacter freundii, Comamonas spp, Pseudomonas aeruginosa, Pseudomonas fluorescenscens, Pseudomonas putida, Pseudomonas stutzeri, Ralstonia pickettii, Staphylococcus aureus, Staphylococcus epidermidis, Staphylococcus lugdenensis, Staphylococcus saprophyticus, Staphylococcus spp, Staphylococcus warneri and Staphylococcus xylosus. Regarding antimicrobial resistance, most of the Gram negative strains were resistant to penicillin and cephalosporins. Gram positive to oxacillin and penicillin 66,67% were multiresistant to more than three antibiotics. The “Termas de Santagua de Chachimbiro” spa presents a diversity of bacterial species and the presence of environmental resistomes. Keywords: mineral medicinal waters; bacterial biodiversity; resistance to antibiotics; Santagua Chachimbiro Spa

A two-year monitoring of Cryptosporidium spp. oocysts and Giardia spp. cysts in freshwater and seawater: A complementary strategy for measuring sanitary patterns of recreational tropical coastal areas from Brazil

Primary contact recreation is an important transmission route of gastroenteric protozoa such as Cryptosporidium and Giardia. However, data on the environmental epidemiology of both protozoa in Brazilian coastal areas still need to be available. The main goal of this study was to perform environmental monitoring and quantify the concentration of Cryptosporidium oocysts and Giardia cysts on the main beaches of the state of Paraná, Brazil, as a complementary tool for measuring the sanitary quality of bathing waters for two years. A total of 144 water samples were harvested monthly for two years from Guaratuba, Caiobá and Matinhos beaches (72 samples of seawater and 72 of freshwater) to search for pathogenic protozoa. Protozoa were concentrated by the membrane filtration technique and visualized by direct immunofluorescence assay (IFA). All positive samples by IFA were submitted for DNA extraction for PCR analysis. Fecal indicator bacteria (FIB) were enumerated by conventional microbiological techniques. Both protozoa were detected on all beaches during the two-year monitoring period. At least one protozoa were detected in 58.3% (n = 14) months of sampling, totaling 24 positive samples. Guaratuba was the most contaminated beach followed by Caiobá and Matinhos. Giardia spp. was detected in 15, Cryptosporidium spp. in seven and both parasites in two samples. Giardia DNA was confirmed on two beaches, and Cryptosporidium was detected for the first time through molecular assays in a coastal area of Brazil. An essential impact of FIB was observed in the first year and a reduction in contamination rates in the second year of monitoring. This is the first study conducted in the country in different environments that composes coastal areas to monitor together parasitological and microbiological quality for extended periods. The monitoring of coastal waters can guide environmental agencies aiming to improve the sanitary quality of beaches and safeguard public health.

The pre-coated photocatalytic ceramic membrane with Bi2O3–TiO2/powdered activated carbon nanoparticles to alleviate ultrafiltration fouling caused by intracellular organic matter of Microcystis aeruginosa

Algal intracellular organic matter (IOM), released during algae's normal growth phase and water treatment processes, has long been a source of significant membrane fouling, considerably limiting the effective use of ultrafiltration(UF) technology. In this study, a Bi-doped TiO2 composite with powdered activated carbon (Bi2O3–TiO2/PAC) was loaded on ceramic UF membranes by vacuum filtration, and the prepared photocatalytic modified ceramic membranes (MCMs) were investigated for the removal of IOM and the mitigation of membrane fouling at different loading levels and under three operating conditions: Dark, Dark-UV, and UV. The results showed that the photocatalytic MCMs were able to remove the protein and humic acid fluorescent components of IOM and decompose or mineralize organic matter with molecular weights of 10–50 kDa. Under the Dark, Dark-UV, and UV conditions, the final normalized flux of MCM-2.88 was significantly increased by 22.6 %, 82.1 %, and 108.0 %, respectively. The hydrophilicity of MCMs not only transformed the interactions between IOM and the membrane into repulsive forces, but also the composite material on the membrane surface transforms the membrane fouling mechanism from intermediate blocking model to cake layer formation. Furthermore, the application of photocatalytic oxidation under the Dark-UV and UV conditions yielded a reduction in both reversible and irreversible fouling. This action led to an increased hydrophilicity and elevated free energy of adhesion with IOM during the filtration process. Moreover, the main fouling mechanism changed into complete or intermediate blocking. These outcomes collectively underscore the capability of MCMs to alleviate membrane fouling induced by IOM. This advancement holds substantial promise for the advancement and widespread implementation of photocatalytic ceramic membrane filtration techniques.

Environmental sustainability of FO membrane separation applications – Bibliometric analysis and state-of-the-art review

Water treatment, product concentration, and resource recovery are few examples of the many areas where the economic promise of osmotic driven membrane separation remains unrealized. The most futuristic and sustainable, osmotic driven membrane separation process which works with-out any external hydraulic energy is forward osmosis (FO) process. This study comprises two parts first is of bibliometric analysis which helps to identify and analyze the current research trend in osmotic membrane filtration technique, and are represented along with nodal network visualization. Desalination and wastewater treatment seem to be the major application of FO technology followed by fertigation, algal dewatering, pharmaceutical and textile industries. The second part is the literature review on major applications of forward osmotic technique shortlisted from bibliometric analysis, which includes recent developments in FO research. An application based critical analysis on thin film nano composite membrane, draw solutes, nano particles for membrane modifications and hybrid FO units were performed. Analysing literatures from 2005 to 2022, this study pinpoints potential applications, future prospects and existing challenges in Forward Osmosis (FO), for the successful implementation of scale-up.

Physicochemical and bacteriological assessment of Wupa wastewater treatment plant effluent and the effluent-receiving Wupa River in Abuja, Nigeria.

The occurrence of pathogens in discharged wastewater effluent may constitute potential public health risks. This study assessed the physicochemical and bacteriological characteristics of water samples taken from the Wupa River in Abuja, Nigeria, which receives the final effluent of the Wupa Wastewater Treatment Plant. Sixty sewage/water samples were collected over 12 months from five sampling points. Coliform bacteria and Escherichia coli were simultaneously enumerated using the membrane filtration technique and Chromocult Coliform Agar. HANNA multiparameter metre was used to measure the physicochemical parameters including temperature, pH, electrical conductivity (EC), dissolved oxygen (DO) and total dissolved solids (TDS). Results of the bacteriological analysis showed that impermissible high mean counts of E. coli (≥ 1.2 × 104 CFU/100 ml) and total coliforms (≥ 5.4 × 104 CFU/100 ml) were detected in 95% and 100% of the water samples respectively. These values exceed the acceptable standard limits. The mean values of physicochemical parameters ranged from 6.3 to 8.7, 20.9 to 27.3 °C, 116 to 325.0 µS/cm, 1.3 to 11.4 mg/l and 98.0 to 180.0 mg/l for pH, temperature, EC, DO and TDS respectively, with all conforming to international and national standards. Wupa River seems to have a minor negative environmental impact, per the physicochemical data obtained in this study. However, the high counts of faecal indicator bacteria demonstrated in the effluent samples were higher than those of the river at both upstream and downstream sites, implying that the river microbial load may increase to constitute an unchecked environmental hazard. Adequate disinfection of the Wupa plant effluent before discharge into the Wupa River is imperative.

A Critical Review on PFAS Removal from Water: Removal Mechanism and Future Challenges

Per and polyfluoroalkyl substances (PFAS) have been extensively employed in a broad range of manufacturing and consumer goods due to their highly persistent nature. PFAS exposure is recognized to pose serious health hazards; therefore, addressing PFAS pollution in water has become a top priority for public health and environmental protection organizations. This review article focuses on the efficiency of different removal techniques (activated carbon, biochar, ion exchange resin, membrane filtration, reverse osmosis, metal-organic frameworks, foam fractionation, ozone fractionation, and destruction techniques) for eliminating different types of short- and long-chain PFAS from water. Hydrophobicity and electrostatic interactions are revealed to be the primary mechanisms for the elimination of PFAS. The efficiency of all techniques to eradicate short-chain PFAS is comparatively lower compared to long-chain PFAS. The destruction techniques are the most efficient but have some drawbacks, including the formation of PFAS precursors and high operational costs. According to the findings from the study, it is anticipated that combined methods will be required to effectively remediate PFAS-contaminated water.

Methods for detection and enumeration of coliforms in drinking water: a review

Abstract Ensuring the microbiological safety of drinking water is of paramount importance to protect public health. Coliform bacteria, including Escherichia coli, serve as key indicators of water contamination and the potential presence of harmful pathogens. Accurate and reliable detection and enumeration of coliforms in drinking water are essential for monitoring water quality and implementing appropriate interventions. This review article provides an overview of various traditional culture-based methods and rapid molecular methods employed for the analysis of coliforms in drinking water, highlighting their strengths, limitations, and advancements. Culture-based methods such as multiple-tube fermentation (most probable number) and membrane filtration techniques have long been used as standard methods for coliform detection. The emerging molecular-based approaches, including polymerase chain reaction (PCR), quantitative PCR, and nucleic acid sequencing offer improved sensitivity, specificity, and turnaround time. This comprehensive review provides a valuable resource for researchers, water quality professionals, and policymakers engaged in the detection and enumeration of coliform bacteria in drinking water. It offers an up-to-date understanding of different methods, their advancements, and the potential integration of novel technologies. By critically evaluating these approaches, this review aims to contribute to the ongoing efforts toward ensuring safe drinking water for all.