Search

Although significant technological advancements have been made in the development of analytical biosensor chips for detecting bacterial strains (E. coli, S. Mutans and B. Subtilis), critical requirements i.e. limit of detection (LOD), fast time of response, ultra-sensitivity with high reproducibility and good shelf-life with robust sensing capability have yet to be met within a single sensor chip. In order to achieve these criteria, we present an electrically-receptive thermally-responsive (ER-TR) sensor chip comprised of simple filter paper used as substrate coated with composite of poly(N-isopropylacrylamide) polymer (PNIPAm) – graphene nanoplatelet (GR) followed by evaporation of Au electrodes for capturing both Gram-positive (S. mutans and B. subtilis) and Gram-negative (E. coli) bacterial cells in real-time. Autoclave water, tap water, lake water and milk samples were tested with ER-TR chip with and without bacterial strains at varying concentration range 10 1 –10 5 cells/mL. The sensor was integrated with in-house built printed circuit board (PCB) to transmit/receive electrical signals. The interaction of E. coli, S. mutans and B. subtilis cells with fibers of PNIPAm-GR resulted in a change of electrical resistance and the readout was monitored wirelessly in real-time using MATLAB algorithm. Finally, prepared ER-TR chip exhibited the reproducibility of 85–97% with shelf-life of up to four weeks after testing with lake water sample. [ABSTRACT FROM AUTHOR]

We have developed a new litmus paper test (DipTest) for detecting Escherichia coli (E. coli) in water samples by performing enzymatic reactions directly on the porous paper substrate. The paper strip consists of a long narrow piece of cellulose blotting paper coated with chemoattractant (at bottom edge), wax hydrophobic barrier (at the top edge), and custom formulated chemical reagents (at reaction zone immediately below the wax hydrophobic barrier). When the paper strip is dipped in water, E. coli in the water sample is attracted toward the paper strip due to a chemotaxic mechanism followed by the ascent along the paper strip toward the reaction zone due to a capillary wicking mechanism, and finally the capillary motion is arrested at the top edge of the paper strip by the hydrophobic barrier. The E. coli concentrated at the reaction zone of the paper strip will react with custom formulated chemical reagents to produce a pinkish-red color. Such a color change on the paper strip when dipped into water samples indicates the presence of E. coli contamination in potable water. The performance of the DipTest device has been checked with different known concentrations of E. coli contaminated water samples using different dip and wait times. The DipTest device has also been tested with different interfering bacteria and chemical contaminants. It has been observed that the different interfering contaminants do not have any impact on the DipTest, and it can become a potential solution for screening water samples for E. coli contamination at the point of source. [ABSTRACT FROM AUTHOR]

A preface to the journal "Hydrobiologia" is presented.

Simple Summary: In biofloc technology systems, organic matter and inorganic substances accumulate in the culture unit mainly due to low water exchange, feed input, high stocking densities, and the level of organic carbon that subsequently increase the bacterial biomass. The organic and inorganic matter in suspension are maintained in a limited concentration to avoid negative effects on animal performance and water quality. This requires the occasional removal of excess solids, which produces an effluent enriched in nutrients, such as nitrogen and phosphorus. The use of integrated aquaculture in which the residues of one species are used as a source of nutrients for another species is an approach which aims to minimize this production of waste. Still, there are aspects of integrated cultures that have to be studied, such as the provision of feed for the different species. Therefore, we evaluated the addition or not of fish feed and microalgae in an integrated shrimp and fish culture regarding animal growth performance and water quality. We found that biofloc is nutritive for fish, but feed is necessary to improve its growth. Moreover, microalgae improved fish survival. However, both of factors did not affect the solids production. This study aims to evaluate a Pacific white shrimp and Nile tilapia integrated system using biofloc technology with or without the addition of the microalgae Scenedesmus obliquus and with or without fish feed supplementation in a two-factor 62-day experiment. The shrimp (2.16 ± 0.01 g) were reared under a density of 400 shrimp m−3 and the fish (1.53 ± 0.12 g) were reared under a density of 522 fish m−3. The microalgae was added to the culture water two times a week. Growth performance, sludge production, and water microbiology were evaluated. Fish feed and the microalgae addition improved fish final biomass in 58% and 14%, respectively (p < 0.05). Fish survival was significantly higher when microalgae was added (93.9 ± 1.8%) compared with the treatments without microalgae addition (86.2 ± 7.6%) (p < 0.05). The yield of the overall system was higher in the treatments with fish feed supplementation (4.2 ± 0.2 kg m−3) compared with no addition (3.9 ± 0.2 kg m−3) (p < 0.05). These results suggest that fish feed supplementation at the rate of 1% of the biomass and microalgae inoculation can improve fish growth performance and system yield, without affecting sludge production and water microbiology. This work is an expansion of a conference paper with the same title. [ABSTRACT FROM AUTHOR]

Digital polymerase chain reaction (dPCR) has emerged as a groundbreaking technology in molecular biology and diagnostics, offering exceptional precision and sensitivity in nucleic acid detection and quantification. This review highlights the core principles and transformative potential of dPCR, particularly in infectious disease diagnostics and environmental surveillance. Emphasizing its evolution from traditional PCR, dPCR provides accurate absolute quantification of target nucleic acids through advanced partitioning techniques. The review addresses the significant impact of dPCR in sepsis diagnosis and management, showcasing its superior sensitivity and specificity in early pathogen detection and identification of drug-resistant genes. Despite its advantages, challenges such as optimization of experimental conditions, standardization of data analysis workflows, and high costs are discussed. Furthermore, we compare various commercially available dPCR platforms, detailing their features and applications in clinical and research settings. Additionally, the review explores dPCR's role in water microbiology, particularly in wastewater surveillance and monitoring of waterborne pathogens, underscoring its importance in public health protection. In conclusion, future prospects of dPCR, including methodological optimization, integration with innovative technologies, and expansion into new sectors like metagenomics, are explored. [ABSTRACT FROM AUTHOR]

The results of five-year (2008-2012) hydrochemical research of the Poprad river, the right bank tributary to the Dunajec, were analyzed in the paper. The Poprad, 167 km long and with the catchment area of 2077.3 km2, flows for over 100 km through the territory of Slovakia, along the length of 31.1 km is a transboundary river, whereas its 31.0 km long reach is situated in Poland. Concerning its abiotic character, it is an eastern upland river of type 15. The research was conducted in three measurement-control points: 1) located in Leluchów on the Polish-Slovak border at 61.1 kilometer of the river course, 2) in Piwniczna-Zdrój - 23.9 km and 3) in Stary Sącz - 2.9 km before the Poprad outlet to the Dunajec. 21 physicochemical indices and 2 microbiological indicators were assessed in the water samples once a month using referential methods. The paper assesses changes of water quality classes and its usable values along the analyzed Poprad river reach. Moreover, statistical differences between the values of individual indices assessed in various measurement-control points were estimated by means of Mann-Whitney U nonparametric test. On the basis of the conducted analyses of the empirical data it was stated that due to the physicochemical indices, water quality along the whole length of the analyzed river reach was good (class II) - in points 1 and 3 it was determined by mean concentration of total suspended solids, whereas in point 2 COD-Mn values. [ABSTRACT FROM AUTHOR]

Low economic profit usually reduces the incentive of producers to operate their wastewater treatment technologies effectively. It is necessary to investigate the performance of environmentally friendly production technologies that reduce wastewater discharges and generate economic outputs simultaneously (EPTWs) in China over the past decade. In this paper, we apply the Malmquist-Luenberger productivity index widely used in the field of economics to evaluate the productivity change of EPTWs for 30 administrative provinces in China during 2003–2015. The pathways of the productivity change are further identified by decomposing the productivity index into two components: technological change and technical efficiency change. The results show that China’s environmental productivity index associated with wastewater reduction had undergone a downward trend, and evident spatial disparities are observed among the 30 provincial regions. Moreover, the changes of China’s environmental productivity over the whole studied period can mainly be attributed to technological progress, while the technical efficiency component has contributed little, although its annual contributing rate is in an increasing trend. [ABSTRACT FROM AUTHOR]

This paper attempts to evaluate the Malaysian water quality indexing method that has been criticized for its ineffectiveness. The indexing method is referred to as the Water Quality Index of the Department of Environment, Malaysia (DOE-WQI). This index was assessed against two other indices (River Ganga Index and Minimal Water Quality Index (WQImin)) and a modified DOE-WQI was also proposed. DOE-WQI and WQImin are physicochemical indices, whereas the River Ganga Index and modified DOE-WQI are indices with the inclusion of a microbiological parameter. The assessment was conducted based on the water quality of tropical rivers in Malaysia, with specific reference to Sarawak River and its tributaries. Water quality in terms of pH, dissolved oxygen, conductivity, turbidity, total suspended solids, biochemical oxygen demand, chemical oxygen demand, ammoniacal nitrogen, and fecal coliform count (FCC) was measured from 18 stations in December 2015, January 2016, and March 2016. Generally, the river was characterized with high FCC with the four indices significantly correlated. The results demonstrated the shortcomings of the existing DOE-WQI; the physicochemical index assigned water quality to a better class than its actual conditions without taking into consideration the FCC. [ABSTRACT FROM AUTHOR]

Keywords: microbialites; microbiome; geobiology; meta-omics approaches; microbiology In the paper by De Anda et al., the authors used metagenomic techniques to examine the specific interactions between taxa in response to environmental perturbations in the freshwater microbialites of Cuatros Ciénegas in Mexico. [Extracted from the article]

Microbial contamination in urban stormwater is one of the most widespread and challenging water quality issues in developed countries. Low impact development (LID) best management practices (BMPs) restore pre-urban hydrology by treating and/or harvesting urban runoff and stormwater, and can be designed to remove many contaminants including pathogens. One particular type of LID BMP, stormwater biofilters (i.e., vegetated media filters, also known as bioinfiltration, bioretention, or rain gardens), is becoming increasingly popular in urban environments due to its multiple co-benefits (e.g., improved hydrology, water quality, local climate and aesthetics). However, increased understanding of the factors influencing microbial removal in biofilters is needed to effectively design and implement biofilters for microbial water quality improvement. This paper aims to provide a holistic view of microbial removal in biofilter systems, and reviews the effects of various design choices such as filter media, vegetation, infauna, submerged zones, and hydraulic retention time on microbial removal. Limitations in current knowledge and recommendations for future research are also discussed. [ABSTRACT FROM AUTHOR]

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is shed in the stool of infected individuals and can be detected in sewage and wastewater contaminated with infected stool. This study is aimed at detecting the virus and its potential survival in sewage and wastewater in Ghana. The cross-sectional study included samples from 16 validated environmental surveillance sites in 7 regions of Ghana. A total of 354 samples composed of wastewater (280) and sewage (74) were collected from November 2020 to November 2022. Overall, 17% of the samples were positive for SARS-CoV-2 by real-time PCR, with 6% in sewage and 11% in wastewater. The highest number of positive samples was collected from the Greater Accra Region (7.3%) with the least recorded in the Bono East Region (0.6%). Further characterization of the positive samples using the next-generation sequencing (NGS) approach yielded two variants: Alpha (B.1.1.7) and Delta (AY.36). Attempts to isolate SARS-CoV-2 in the Vero cell line were not successful probably due to the low viral load concentrations (Ct values > 35) or prolonged exposure to high temperatures rendering the virus noninfectious. Our findings suggest that SARS-CoV-2 RNA in sewage and wastewater may not be infectious, but the prevalence shows that the virus persists in the communities within Ghana. [ABSTRACT FROM AUTHOR]

Growing areas of sealed surfaces, rising water needs due to industry development, increasing populations, and climatic changes affect precipitation patterns and form a vision of the future in which meteoric water storage may become almost an obligatory activity. The aim of this paper was to identify the amounts and, to some degree, the quality of microorganisms present in rainwater collected from different types of rooftops of utility buildings in the spring-summer season. Apart from the classic culture plate method complemented by flow cytometry. The results of performed analyses explicitly show that rainwater collected from rooftops and directly from air prove to be microbially contaminated to a substantial degree, which includes pathogenic coliforms and faecal streptococci. Waters collected after dry periods also contained bacteria like Clostridium perfingens. The findings rule out the possibility of using rainwater collected from roof surfaces of utility buildings before its treatment. [ABSTRACT FROM AUTHOR]

Background: Antibiotic resistance has been referred to as 'the greatest malice of the 21st century' and a global action plan was adopted by the World Health Assembly in 2015. There is a wealth of independent studies regarding antibiotics and resistant bacteria in humans, animals and their environment, however, integrated studies are lacking, particularly ones that simultaneously also take into consideration the health related behaviour of participants and healthcare providers. Such, 'One health' studies are difficult to implement, because of the complex teamwork that they entail. This paper describes the protocol of a study that investigates 'One health' issues regarding antibiotic use and antibiotic resistance in children and their environment in Indian villages.Methods/design: Both quantitative and qualitative studies are planned for a cohort of children, from 6 villages, and their surrounding environment. Repeated or continues data collection is planned over 2 years for quantitative studies. Qualitative studies will be conducted once. Studies include parents' health seeking behavior for their children (1-3 years of age at the onset), prescribing pattern of formal and informal healthcare providers, analysis of phenotypic antibiotic resistance of Escherichia coli from samples of stool from children and village animals, household drinking water, village source water and waste water, and investigation on molecular mechanisms governing resistance. Analysis of interrelationship of these with each other will also be done as basis for future interventions. Ethics approval has been obtained from the Institutional Ethics Committee R.D. Gardi Medical College, Ujjain, India (No: 2013/07/17-311).Discussion: The findings of the study presented in this protocol will add to our knowledge about the multi-factorial nature of causes governing antibiotic use and antibiotic resistance from a 'One health' perspective. Our study will be the first of its kind addressing antibiotic use and resistance issues related to children in a One-health approach, particularly for rural India. [ABSTRACT FROM AUTHOR]

There is a widespread need for the use of quantitative microbial risk assessment (QMRA) to determine reclaimed water quality for specific uses, however neither faecal indicator levels nor pathogen concentrations alone are adequate for assessing exposure health risk. The aim of this study was to build a conceptual model representing factors contributing to the microbiological health risks of reusing water treated in maturation ponds. This paper describes the development of an unparameterised model that provides a visual representation of theoretical constructs and variables of interest. Information was collected from the peer-reviewed literature and through consultation with experts from regulatory authorities and academic disciplines. In this paper we explore how, considering microbial risk as a modular system, following the QMRA framework enables incorporation of the many factors influencing human exposure and dose response, to better characterise likely human health impacts. By using and expanding upon the QMRA framework we deliver new insights into this important field of environmental exposures. We present a conceptual model of health risk of microbial exposure which can be used for maturation ponds and, more importantly, as a generic tool to assess health risk in diverse wastewater reuse scenarios. [ABSTRACT FROM AUTHOR]

Objectives: This paper describes and comments on contemporary legislation concerning prevention of epidemics caused by contaminated drinking water from public water supplies in the Czech Republic.Methods: Suggestions are made for removing existing legislative shortcomings, clarifying diction of existing laws and expanding sanctions and penalties for health injury caused by providers and operators of public drinking water.Results: The author reflects on improving legislation concerning the compensation of victims of contaminated water with reference to the aftermath of a local epidemic in the Dejvice District of Prague.Conclusion: The issues raised should be addressed since better legislation can significantly contribute to the limitation of water-borne epidemics and their consequences. [ABSTRACT FROM AUTHOR]

Water is one of the most important natural resource, a social requirement and an important factor in the ecological balance. Water from springs is good for direct consumption if the soil is not contaminated. The population, who is not benefiting from the centralized water, is supplied in different area from springs. Water from springs is good for direct consumption if the area around groundwater is not contaminated. Groundwater pollution, caused by human activities related to the agriculture, industry and population growth, is a current problem with serious consequences to human health. The aim of this paper was to assess the physico-chemical and microbiological qualities of springs water from Abrud-Câmpeni area, Alba County, Roamnia. The water samples were taken in 2018 from 11 functional springs. Of these, only three sources are potable, the rest of the springs are microbiologically contaminated. The average concentration of NO3- - in the investigated springs from Abrud-Câmpeni area is 6.1 mg/l. Monthly, between January and December 2018, the variation of the nitrate content in the water from the spring Lucia (Sohodol village) was also monitored. Fluctuations were observed with maximum in the cold season (February), 4.37 mg/l, and minimum in the summer (August), 2.14 mg/l. In order to identify the factors that lead to the variation of the NO3- - content in water, statistical mathematical models were developed. The parameters studied were: atmospheric temperature, the amount of precipitation, respectively the freeze/thaw cycle. The concordance indicators demonstrated a satisfactory correlation between the variation of those factors and the variation of the NO3- - content in water. [ABSTRACT FROM AUTHOR]

The bacteriological characteristics of rainwater harvested from a typical rooftop were progressively studied for a period of nine (9) months. The study area, Oyoko, is a rural community considered as a typical farming area and located about 30 km from Kumasi, the capital city of Ashanti Region of Ghana. The collected rainwater samples were analyzed for Escherichia coli (E. coli) and salmonella. The entire E. coli counts varied from 0-60 CFU/100 ml and were absent on 39 observations out of total of 84 observations (replicate samples), representing 46.4%. Whiles the entire salmonella counts ranged from 0-78 CFU/100ml and only 10 observations out of the 84 were absent, which represents 11.9%. Both E. coli and salmonella showed higher concentration during early stages of continuous rainfall but, progressively reduced during later part of rainfall. The main cause of this phenomenon can be attributed to the deposition and accumulation of pollutant materials on the rooftop and catchment areas typically during the dry seasons as a result of wind-blown dirt particles and other environmental pollutants. The high bacteriological constituents in the early-stage harvested rainwater consequently have some proven significant health implications from their direct consumption. It is therefore imperative for the community to know the best time interval to harvest their rainwater as rainfall progresses, and also know any health implications associated with the harvested rainwater that goes into their storage tanks for consumption through progressive monitoring of the quality. [ABSTRACT FROM AUTHOR]

The field of treatment wetlands (TWs) is rapidly expanding and, arguably, is tasked with studying and understanding one of the most complex water treatment systems available. Microbial communities are generally considered to be responsible for the majority of wastewater constituent degradation in TWs. However, they are also known to be spatially heterogeneous, temporally dynamic, as well as structurally and functionally diverse. Presented here is a meta-analysis of all peer reviewed TW journal articles which utilized a microbial community assessment methodology over the period of 1988 to July 2016. A total of 1101 papers were reviewed, 512 from 1988 to 2012, 215 of which included a microbial community assessment aspect and were subsequently classified as representing past research, and 589 from 2013 to July 2016, 196 of which were classified as representing current TW microbial community research. In general, TW microbial community research has increased over time, with a marked surge in the past four years. Microbial community structure is currently the most commonly used methodological type followed by activity, enumeration and function, respectively. Areas of research focus included nitrogen transformations (156), organic degradation (33), and emerging contaminants (32), with general characterization studies also accounting for a significant proportion (243). Microbial communities from a range of TW systems have been investigated over the last four years with meso-scale (10-1000 L) being the most commonly studied system size followed by large-scale (>100,000 L), micro-scale (<10 L), and pilot-scale (1000-100,000 L). Free water surface flow (SF), horizontal subsurface flow (HF), and vertical flow (VF) systems are being studied in approximately equal proportions with the majority of studies focused on gaining fixed media/biofilm samples for analysis (rather than from the rhizosphere or interstitial water). Looking at efforts from a regional perspective shows Asia to be publishing the majority of research with a main focus on VF systems and structural community assessment. European and North American studies are generally more evenly distributed among structure, function, activity, and enumeration with the majority of studies completed on HF systems. South America, Africa, and Oceania published fewer studies but focused on structural community assessment with a selection of HF, SF and VF investigations. Great strides are being made in the field of microbial community assessment in TWs with functional assessment methods being developed, better utilized, and being related directly to water treatment. The use of high-powered metagenomics sequencing such as Illumina HiSeq instrumentation is on the rise, as is the development and utilization of functional assays such as DNA microarrays and community level physiological profiling allowing for more complete community assessment. Used in concert with activity, enumeration and newly implemented stable isotope methodologies, the field of TWs is certainly moving away from the black-box understanding of the past. [ABSTRACT FROM AUTHOR]

This paper uses a two-fold multi-criteria decision-making (MCDM) approach applied for the first time to the field of microbial management of drinking water distribution systems (DWDS). Specifically, the decision-making trial and evaluation laboratory (DEMATEL) was applied removing the need for reliance on expert judgement, and analysed interdependencies among water quality parameters and microbiological characteristics of DWDS composed of different pipe materials. In addition, the fuzzy technique for order preference by similarity to ideal solution (FTOPSIS) ranked the most common bacteria identified during trials in a DWDS according to their relative abundance while managing vagueness affecting the measurements. The novel integrated approach presented and proven here for an initial real world data set provides new insights in the interdependence of environmental conditions and microbial populations. Specifically, the application shows as the bacteria having associated the most significant microbial impact may not be the most abundant. This offers the potential for integrated management strategies to promote favourable microbial conditions to help safeguard drinking water quality. [ABSTRACT FROM AUTHOR]

This paper examines the recovery of the enteric adenovirus human adenovirus 40 (HAdV 40) by cross-flow ultrafiltration and interprets recovery values in terms of physicochemical interactions of virions during sample concentration. Prior to ultrafiltration, membranes were either blocked by exposure to calf serum (CS) or coated with a polyelectrolyte multilayer (PEM). HAdV 40 is a hydrophobic virus with a point of zero charge between pH 4.0 and pH 4.3. In accordance with predictions from the extended Derjaguin-Landau-Verwey-Overbeek theory, the preelution recovery of HAdV (rpre) from deionized water was higher with PEMcoated membranes (rprePEM=74.8%±9.7%) than with CS-blocked membranes (rpreCS =54.1%±6.2%). With either membrane type, the total virion recovery after elution (rpost) was high for both deionized water (rpostPEM=99.5%±6.6% and rpost CS =98.8%± 7.7%) and tap water (rpostPEM=89%±15% and rpost CS =93.7%±6.9%). The nearly 100% recoveries suggest that the polyanion (sodium polyphosphate) and surfactant (Tween 80) in the eluent disrupt electrostatic and hydrophobic interactions between the virion and the membrane. Addition of EDTA to the eluent greatly improved the elution efficacy (rpostCS =88.6%±4.3% and rpostPEM=87.0%±6.9%) with surface water, even when the organic carbon concentration in the water was high (9.4±0.1 mg/liter). EDTA likely disrupts cation bridging between virions and particles in the feed water matrix or the fouling layer on the membrane surface. For complex water matrices, the eluent composition is the most important factor for achieving high virion recovery. [ABSTRACT FROM AUTHOR]

Studies on coral reefs increasingly combine aspects of science and technology to understand the complex dynamics and processes that shape these benthic ecosystems. Recently, the use of advanced computational algorithms has entered coral reef science as new powerful tools that help solve complex coral reef related questions, which were unsolvable just a decade earlier. Some of these advanced algorithms consist of Computational Intelligence (CI) approaches, a branch of Artificial Intelligence that uses intelligent systems to address complex real-world problems yielding more robust, tractable and simpler solutions than those obtained by conventional mathematical techniques. This paper describes the most commonly used CI techniques related to coral reefs and the main improvements obtained with these methods over classical algorithms in this field. Some recommendations are given for the application of CI techniques to complex coral reef related problems, and vice-versa, for the application of novel coral reef dynamics concepts to improve the Coral Reef Optimization (CRO) algorithm, an optimization method inspired by coral reef dynamics. [ABSTRACT FROM AUTHOR]

This paper comparatively assessed the effectiveness of potable water filtration methods, commonly used in the hinterlands in some Ghanaian communities. Physico-chemical and microbiological analysis were carried out on pond, dam and river water samples, using spectrophotometric, pour plate count and the most probable number (MPN) methods. For the unfiltered water samples the total dissolved solids (TDS) and colour were the only parameters with values within recommended standards. The other parameters, total suspended solids (TSS), turbidity, total coliforms and bacterial counts levels were above their standard recommended values. All the filtration methods showed reduction in the levels or better accepted values of the physico-chemical and microbiological parameters. The ceramic filters and the household sand filters showed outstanding results, with all analysed parameters being within the acceptable standards levels. These two methods could be promoted for use to treat untreated drinking water. It is envisaged that a combination of a number of these methods would produce even better results, especially when agents such as alum and activated carbon are included. Follow-up research in this regard is therefore recommended. [ABSTRACT FROM AUTHOR]

Here we provide seasonal data on the concentrations of total coliform, Escherichia coli and Enterococcus spp. and six opportunistic pathogens (Acanthamoeba spp., Legionella spp., Legionella pneumophila, Mycobacterium avium, Mycobacterium intracellulare, and Pseudomonas aeruginosa) of public health significance in 24 tank water samples over six monthly sampling events from August 2015 to March 2006. Quantitative PCR (qPCR) assays were chosen for the quantification of six opportunistic pathogens and culture-based methods were used for the enumeration of fecal indicators. The data fle has been stored in a publicly available repository. The data on concentrations of opportunistic pathogens in RHRW will provide information for rainwater users regarding potential seasonality of risks. Quantitative data presented in this study can be used to perform quantitative microbial risk assessment (QMRA) of RHRW for various potable and nonpotable uses. Data can be used by health regulators to develop guidelines related to RHRW. [ABSTRACT FROM AUTHOR]

In the article, the authors discuss the need to improve water quality surveillance to ensure safe drinking water for all beyond national water quality surveys. Also cited are the study which analyzed United Nations International Children's Fund (UNICEF) Multiple Indicator Cluster Survey (MICS) data of water quality in low- and middle-income countries, and the state of fecal contamination with escherichia coli (E. coli) of drinking water at point of use (PoU) and point of collection (PoC).

Cryptosporidium, an intestinal protozoan pathogen, is one of the leading causes of diarrhea in healthy adults and death in children. Detection of Cryptosporidium oocysts has become a high priority to prevent potential outbreaks. In this paper, a label-free interdigitated-based capacitive biosensor has been introduced for the detection of Cryptosporidium oocysts in water samples. Specific anti-Cryptosporidium monoclonal antibodies (IgG3) were covalently immobilized onto interdigitated gold electrodes as the capture probes, and bovine serum albumin was used to avoid non-specific adsorption. The immobilization of the antibodies was confirmed by measuring the change in the contact angle. The detection was achieved by measuring the relative change in the capacitive/dielectric properties due to the formation of Cryptosporidium-antibody complex. The biosensor has been tested for different concentrations of Cryptosporidium. The results show that the biosensor developed can accurately distinguish different numbers of captured cells and densities on the surface of the biosensor. The number of Cryptosporidium oocysts captured on the electrode surface was confirmed using a fluorescein isothiocyanate (FITC) immunofluorescence assay. The response from the developed biosensor has been mainly dependent on the concentration of Cryptosporidium under optimized conditions. The biosensor showed a linear detection range between 15 and 153 cells/mm2 and a detection limit of 40 cells/mm2. The label-free capacitive biosensor developed has a great potential for detecting Cryptosporidium in environmental water samples. Furthermore, under optimized conditions, this label-free biosensor can be extended for detection of other biomarkers for biomedical and environmental analyses. [ABSTRACT FROM AUTHOR]

The ever-increasing need for high-quality drinking and process waters, and growing public awareness about possible contamination, drive efforts for the further development of automated control of water treatment plants. For example, membrane filtration processes and reverse osmosis in particular are generally regarded as a safe barrier for inorganic, organic, and microbial contamination. Yet, to ensure the final water quality and to increase the confidence of the end-user, intensive and preferably online monitoring should be further implemented as an early-warning tool to control membrane integrity and to prevent microbial regrowth in the distributing network. In this paper, we test the applicability of flow cytometry and cytometric fingerprinting for a full-scale water treatment plant. We demonstrate in a full-scale water treatment plant that flow cytometry can be used as online monitoring tool and that changes in water quality can be observed, which are not monitored by commonly used online quality parameters. Furthermore, we illustrate with ultrafiltration that process conditions impact the flow cytometric cell counts. Bacterial monitoring: Let it flow Flow cytometry can be used as an online, automated tool to monitor water quality in full-scale water treatment plants. The presence of bacteria in high concentrations in water leads to the unwanted growth of biofilms, which can damage water treatment equipment through microbiologically influenced corrosion. Biofilms can also host pathogenic bacteria, leading to water contamination upon their shedding. Monitoring microbial communities in water treatment plants is thus crucial, and a team led by Bart De Gusseme at Ghent University in Belgium demonstrate that online flow cytometry is capable of achieving this in high throughput and at single-cell resolution. Monitoring at different stages of the treatment plant, their method provides important insights into microbiological dynamics that are unattainable through commonly used online quality parameters, and additionally finds that bacterial concentrations are directly related to process operations. [ABSTRACT FROM AUTHOR]

Understanding the swimming characteristics of micro-organisms is significant for modelling the migration of motile cells and corresponding ecological risk assessments associated with harmful algae in oceans and estuaries. Presented in this paper is an experimental and numerical investigation of swimming characteristics of a typical gyrotactic micro-organism, Heterosigma akashiwo (H. akashiwo) in water, based on the technology of planar laser-induced fluorescence and the finite volume method. Two-dimensional swimming velocity of algal cells are obtained by analyzing cells' trajectories in the vertical plane, and three-dimensional swimming velocity is reconstructed based on the assumption that cells' swimming is isotropic in the horizontal plane. Four important parameters are given to reflect the swimming characteristics of gyrotactic cells in still water, including the mean swimming speed (Vs = 146 μm/s), the relative strength of reorientation by gravitational torque to rotational diffusion (λ = 1.96), the time scale of reorientation (B = 5.6 s), and rotational diffusivity (Dr = 0.046 rad2/s). A database of the ambient vorticity, mean swimming velocity and diffusivity tensor is established, by solving Fokker-Planck equation for the probability density function of cells' swimming under the combined action of gravity, rotational diffusion, and the ambient vorticity. The mean swimming velocity and translational diffusion tensor of H. akashiwo are found to change with the horizontal and vertical vorticity. It is also shown that gyrotactic cells swim in a given direction for a weak horizontal vorticity, in contrast to cells' tumbling and being trapped for a strong horizontal vorticity. [ABSTRACT FROM AUTHOR]

A new variation of a method for quantifying cellular adenosine triphosphate (cATP) is described. The variation permits differentiation between cATP from bacteria and cATP from fungi. This paper describes the process by which the new differential cATP method was developed and validate in both laboratory and field tests. Laboratory tests using bacteria, yeasts and filamentous fungi demonstrated that cATP observed in ≥5 μm and <5 μm size-fractions, respectively were consistently within ±10% of predicted concentrations. The field evaluation during which four participating metalworking fluid (MWF) compounders collectively tested >250 used MWF samples, confirmed that the differential protocol reliably detected fungal contamination when it was present. [ABSTRACT FROM AUTHOR]

Bloom-forming freshwater cyanobacterial genera pose a major ecological problem due to their ability to produce toxins and other bioactive compounds, which can have important implications in illnesses of humans and livestock. Cyanobacteria such as Microcystis, Anabaena, Oscillatoria, Phormidium, and Aphanizomenon species producing microcystins and anatoxin-a have been predominantly documented from most South Korean lakes and reservoirs. With the increase in frequency of such blooms, various monitoring approaches, treatment processes, and prediction models have been developed in due course. In this paper we review the field studies and current knowledge on toxin producing cyanobacterial species and ecological variables that regulate toxin production and bloom formation in major rivers (Han, Geum, Nakdong, and Yeongsan) and reservoirs in South Korea. In addition, development of new, fast, and high-throughput techniques for effective monitoring is also discussed with cyanobacterial bloom advisory practices, current management strategies, and their implications in South Korean freshwater bodies. [ABSTRACT FROM AUTHOR]

In the present study, we evaluated the effects of different environments on the filtering rate (FR), mortality, and biodeposition (BD) of the freshwater mussel Unio douglasiae in bloom waters containing the toxic cyanobacterium Microcystis aeruginosa. The mean FR of 19 selected individuals (shell length, 5.0–9.8 cm) was 0.30 ± 0.03 L g − 1 h − 1 (range = 0.24 – 0.35 L g − 1 h − 1 ). Shell length was strongly correlated with both net and gross BD of mussels (P < 0.0001). The mean FR was higher in river water (0.405 ± 0.052 L g − 1 h − 1 ) than in lake water (0.304 ± 0.051 L g − 1 h − 1 ). In contrast, the BD of mussels was higher in RW (0.671 ± 0.609 mg g − 1 h − 1 ) than in LW (0.275 ± 0.027 mg g − 1 h − 1 ). For algal species, the FR of mussels ranged from 0.114 ± 0.024 to 0.553 ± 0.019 L g − 1 h − 1 . The FR of U. douglasiae was higher in river water (mainly diatoms), whereas BD was higher in lake water (mainly Microcystis). U. douglasiae did not prefer toxic M. aeruginosa, which was significantly accumulated in pseudofaeces and faeces. The maximum FR of U. douglasiae in algal bloom water was recorded at a water temperature of 25°C and water depth of 50 cm. Moreover, the in situ mortality of U. douglasiae was strongly affected by water temperature and nitrogen concentration. Overall, U. douglasiae can enhance water quality in eutrophic areas by removing dominant cyanobacteria, although its removal efficiency depends on environmental parameters and site of introduction. [ABSTRACT FROM AUTHOR]

Here, we examine the geobiological response to a whole-lake alum (aluminum sulfate) treatment (2016) of Base Mine Lake (BML), the first pilot-scale pit lake established in the Alberta oil sands region. The rationale for trialing this management amendment was based on its successful use to reduce internal phosphorus loading to eutrophying lakes. Modest increases in water cap epilimnetic oxygen concentrations, associated with increased Secchi depths and chlorophyll-a concentrations, were co-incident with anoxic waters immediately above the fluid fine tailings (FFT) layer post alum. Decreased water cap nitrate and detectable sulfide concentrations, as well as increased hypolimnetic phospholipid fatty acid abundances, signaled greater anaerobic heterotrophic activity. Shifts in microbial community to groups associated with greater organic carbon degradation (i.e., SAR11-LD12 subclade) and the SRB group Desulfuromonodales emerged post alum and the loss of specialist groups associated with carbon-limited, ammonia-rich restricted niches (i.e., MBAE14) also occurred. Alum treatment resulted in additional oxygen consumption associated with increased autochthonous carbon production, watercap anoxia and sulfide generation, which further exacerbate oxygen consumption associated with on-going FFT mobilized reductants. The results illustrate the importance of understanding the broader biogeochemical implications of adaptive management interventions to avoid unanticipated outcomes that pose greater risks and improve tailings reclamation for oil sands operations and, more broadly, the global mining sector. [ABSTRACT FROM AUTHOR]

This study tests if rainfall regime and estuary hydrodynamics affect ecological picocyanobacterial patterns. We statistically related rainfall with picocyanobacteria (flow cytometry) and water quality data from a seven-year-long survey of Guanabara Bay (GB). The quality of GB's water varies spatially, depending on pollution hotspots, tidal influence, and water circulation patterns. It also varies seasonally, depending on the rainfall regime. Our results showed that rainfall regularly makes water quality and microbiology of the inner estuarine regions more like the tributaries' environment. We found that phycocyanin-rich and phycoerythrin-rich picocyanobacterial abundances are associated with riverine and marine waters, respectively. Besides affecting GB's water quality, rainfall governs its picocyanobacterial distribution and ecology. Thus, climate changes may influence the balance of the picocyanobacterial groups in tropical estuaries. Furthermore, the omnipresence of picocyanobacterial groups found in GB, such as Synechococcus and Cyanobium, highlights their ecological role in tropical estuaries, as seen in the open ocean. [ABSTRACT FROM AUTHOR]

Good quality water is odourless, colourless, and free from faecal pollution, and a satisfactory safe supply must be made available to consumers. The study assessed consumer preference and quality of sachet water sold and consumed in the Sunyani Municipality of Ghana. A cross-sectional study design was used, and data were collected using a structured questionnaire from a sample size of 500 respondents. A total of twenty (20) samples of sachet water commonly sold and consumed in the Sunyani Municipality were also collected and analyzed for bacteriological and physicochemical parameters. Out of these 20 samples, 10 samples of sachet water were collected from the production site and the other 10 samples from the market site. Results showed that respondents' choice of sachet water was based on several indicators. While 70% (350/500) of consumers indicated that sachet water had taste, 58% (290/500) of them were not enthused when the water had colour. Using smell as an indicator, 71% of consumers have had an experience with sachet water smell being questionable. Water taste (p < 0.001), colour of water (p < 0.001), smell (p < 0.001), and increase in cost (p < 0.001) were found as determinants of consumer preference. Consumers who said the colour of water informed their decision when buying sachet water were seven times more likely to have a preference for a particular brand (OR 7.057, CI: 4.474–11.133). Those who checked for expiry dates when buying water (OR 4.871, CI: 3.110–7.628) and those who looked out for Food and Drugs Authority stamp (OR 4.433, CI: 2.806–7.003) were both four times more likely to have a preference for a particular brand. Water quality tests also indicated that 30% of all water samples collected from the production site were contaminated with total coliforms and 50% of sachet water samples collected from the markets were also contaminated with coliforms. The same brands of sachet water that contained total coliforms from the production site were the same brands that contained total coliforms selected from the market. From this study, only total coliforms other than Escherichia coli were detected in the water samples analyzed. It was observed that the evaluated physicochemical parameters of the water analyzed were within the accepted WHO limits. It is recommended that consumers be educated about the indicators to look out for when buying sachet water and, also, that regulatory bodies be empowered to ban the sale of unwholesome brands of sachet water on the market. [ABSTRACT FROM AUTHOR]

Background. Freeze-thaw influences soil-dissolved nitrogen (N) pools due to variations in bacterial communities in temperate regions. The availability of soil water is important to soil biogeochemical cycles under frozen conditions. However, it is unclear how soil water content (SWC) mediates the effects of freeze-thaw on soil-dissolved N pools and bacterial communities. Method. In this study, freeze-thaw microcosms were incubated at three levels of SWC, including 10% (air-dried soils), 15% (natural SWC), and 30% (wet soils). In addition to measuring soil-dissolved N pools, variations in bacterial communities were examined using high-throughput sequencing. Results and Conclusions. Total dissolved N (TDN), NO3--N, NH4+-N, microbial biomass N (MBN), and net N mineralization rate (NNMR) were significantly influenced by SWC, freeze-thaw, and their interaction (NH4+-N excluded). N immobilization was inhibited under both low and high SWC, which was accompanied by varied bacterial community composition. However, only higher SWC substantially modified the freeze-thaw effects on the soil-dissolved N pools, characterized by a decrease in N mineralization (especially for the content of NO3--N and NNMR) and an increase in N immobilization (MBN). These scenarios could be significantly correlated to variations in bacterial community composition based on redundancy analysis, especially by species belonging to Bacteroidetes, Nitrospirae, Alphaproteobacteria, Gemmatimonadetes, and Verrucomicrobia (Spearman's correlations). In conclusion, bacterial species passed through biotic (bacterial species) and abiotic filters (soil N pools) in response to freeze-thaw under varied SWC. [ABSTRACT FROM AUTHOR]

In this study, a yeast strain with an outstanding NH3-N degradation ability was isolated from the sediment of a black-odor water channel in Guangdong Province, China. Based on phenotypic and phylogenetic analysis, this strain was identified as Pichia kudriavzevii GW1. The optimum conditions for NH3-N degradation by the GW1 strain were as follows: 0.3% inoculum concentration, 1.5 L/min aeration, pH 7, and a temperature of 35°C. Under optimized conditions, the GW1 strain degraded 95.5% of the NH3-N. The strain was then added to simulated black-odor water under optimal degradation conditions to investigate changes to the bacterial community over time. 16S rRNA sequencing of samples collected on days 0, 7, 14, and 21 showed that, in the presence of the GW1 strain, the relative abundances of the phyla Proteobacteria, Bacteroidetes, Chloroflexi, and Firmicutes increased in the black-odor water. In addition, the relative abundance of Propionivibrio, a known NH3-N degrading genus, increased. This study will facilitate the use of microbiological methods to repair black-odor water. [ABSTRACT FROM AUTHOR]

Pseudoalteromonas is a globally distributed marine-associated genus that can be found in a broad range of aquatic environments, including in association with macroalgal surfaces where they may take advantage of these rich sources of polysaccharides. The metabolic systems that confer the ability to metabolize this abundant form of photosynthetically fixed carbon, however, are not yet fully understood. Through genomics, transcriptomics, microbiology, and specific structure-function studies of pathway components we address the capacity of newly isolated marine pseudoalteromonads to metabolize the red algal galactan carrageenan. The results reveal that the κ/ι-carrageenan specific polysaccharide utilization locus (CarPUL) enables isolates possessing this locus the ability to grow on this substrate. Biochemical and structural analysis of the enzymatic components of the CarPUL promoted the development of a detailed model of the κ/ι-carrageenan metabolic pathway deployed by pseudoalteromonads, thus furthering our understanding of how these microbes have adapted to a unique environmental niche. Hettle et al. investigate the ability of marine Pseudoalteromonas sp. to metabolise carrageenan, a polysaccharide abundant in red algae. They isolate and characterise previously unstudied strains and find that the recently identified κ/ι-carrageenan specific polysaccharide utilization locus (CarPUL) is required for growth on carrageenan, and biochemically map out many of the steps. [ABSTRACT FROM AUTHOR]

The ocean pH is decreasing in response to the increasing anthropogenic CO SB 2 sb emissions (Ocean Acidification; OA). This clear trend of ocean warming and acidification was documented in the fifth Assessment Report (AR5) by Intergovernmental Panel on Climate Change (IPCC). Keywords: microbial community; marine environment; ecosystem; warming; ocean acidification EN microbial community marine environment ecosystem warming ocean acidification 1 3 3 08/12/21 20210809 NES 210809 The World Ocean is undergoing rapid and substantial changes, particularly, in terms of warming and acidification. [Extracted from the article]

Marine organisms comprising animals and plants are wealthiest sources of bioactive compounds possessing various pharmacological properties specifically: free radical scavenging, antitumor, antimicrobial, analgesic, neuroprotective and immunomodulatory. Marine drugs provide an alternative source to meet the demand of effective, safe and low-cost drugs that are rising with the continuously growing world population. Cancer is one of the leading reasons of mortality in western nations in contrast to communicable diseases of developing nations. In spite of outstanding developments in cancer therapy in past three decades, there is still an insistent necessity for innovative drugs in the area of cancer biology, especially in the unexplored area of marine anticancer compounds. However, recent technological innovations in structure revelation, synthetic creation of new compounds and biological assays have made possible the isolation and clinical assessment of innumerable unique anticancer compounds from marine environment. This review provides an insight into the anticancer research so far conducted in the area of the marine natural products/synthetic derivatives, their possible molecular targets and the current challenges in the drug development. [ABSTRACT FROM AUTHOR]

Namibia has experienced challenges in the provision of drinking water to its population. A combination of various solutions should be explored to provide drinking water to the population. In this study, a combination of the raw water treatment with the Grifaid® filters and the compliance monitoring of microbial quality using the hydrogensulphide test kit was tested in two villages in Northern Namibia and one informal settlement in central Windhoek. The efficiency of treatment by site operators was limited as 100 % of samples taken at two of the sampling sites were positive for faecal contamination. Only at the Windhoek sampling site was the treatment of raw water by site operators partially successful, as 67 % of the treated water samples taken were negative for faecal contamination. Concentrations of faecal coliforms in the control samples ranged from below 0 to 6 CFUs/100 mL, with the correspondence rates with the H2S kit test ranging from 20 to 80 %. Recontamination of the water after treatment is the most likely cause of the positive signal in the H2S kit. The site operators found the Grifaid® filters easy to use, but stressed that proper training is required for operating the filters. The users stated that the use of the Grifaid® filters are only suitable as a short-term solution in drinking water provision to the target communities. Future research will have to focus on the testing of the chemical and physical characteristics of raw and treated water; and more detailed examination of the microbial composition of the water samples will have to be conducted. In addition, the citizen-science strategy will have to be modified to assist the community in preventing recontamination of the treated water. [ABSTRACT FROM AUTHOR]

Water system degradation has a severe impact on daily life, especially in developing countries. However, microbial changes associated with this degradation, especially changes in microbes related to sulfur (S) cycling, are poorly understood. In this study, the abundance, structure, and diversity of sulfate-reducing microorganisms (SRM) and sulfur-oxidizing microorganisms (SOM) in the sediments from the Ziya River Basin, which is polluted by various human interventions (urban and agricultural activities), were investigated. Quantitative real-time PCR showed that the S cycling-related (SCR) genes (dsrB and soxB) were significantly elevated, reaching 2.60 × 107 and 1.81 × 108 copies per gram of dry sediment, respectively, in the region polluted by human urban activities (RU), and the ratio of dsrB to soxB abundance was significantly elevated in the region polluted by human agricultural activities (RA) compared with those in the protected wildlife reserve (RP), indicating that the mechanisms underlying water system degradation differ between RU and RA. Based on a 16S rRNA gene analysis, human interventions had substantial effects on microbial communities, particularly for microbes involved in S cycling. Some SCR genera (i.e., Desulfatiglans and Geothermobacter) were enriched in the sediments from both RA and RU, while others (i.e., Desulfofustis and Desulfonatronobacter) were only enriched in the sediments from RA. A redundancy analysis indicated that NH4+-N and total organic carbon significantly influenced the abundance of SRM and SOM, and sulfate significantly influenced only the abundance of SRM. A network analysis showed high correlation between SCR microorganisms and other microbial groups for both RU and RA, including those involved in carbon and metal cycling. These findings indicated the different effects of different human interventions on the microbial community composition and water quality degradation. [ABSTRACT FROM AUTHOR]

Microfluidic channels filled with spatially periodic arrays of impermeable obstacles have been proved successful for the size-based continuous separation of mesoscopic objects suspended in a buffer solution with unprecedented resolution. To date however, this technique - referred to as Deterministic Lateral Displacement (DLD) - has been implemented only for small volume samples, mainly for analytical purposes. In this article, we investigate the feasibility of the DLD separation technique for water purification from bacteria. The accurate numerical solution of the three-dimensional Stokes flow problem is used to establish the hydraulic resistance of several different geometries of the unit periodic cell. Results suggest that DLD-based microfilters resulting from numbering-up DLD microseparation units could provide sizeable flowrates and could prove competitive when compared to membrane-based modules. [ABSTRACT FROM AUTHOR]

We sampled the tap water of seven unique, full-scale drinking water distribution systems at different locations as well as the corresponding treatment plant effluents to evaluate the impact of distribution and the potential presence of a core drinking water microbiome. The water was also sampled during network flushing to examine its effect on the microbial ecology. While a core microbiome dominated by Gammaproteobacteria was found using 16S rRNA gene pyrosequencing, an increase in biomass was detected in the networks, especially during flushing. Water age did not significantly impact the microbiology. Irrespective of differences in treatment plants, tap water bacterial communities in the distinct networks converged and highly resembled the flushed water communities. Piping biofilm and sediment communities therefore largely determine the final tap water microbial quality, attenuating the impact of water source and treatment strategy and highlighting the fundamental role of local physicochemical conditions and microbial processes within infrastructure micro-niches. [ABSTRACT FROM AUTHOR]

A research was undertaken to assess the key parameters which impact the drinking water quality at household and community level in Nirmal Gram Panchayats (fully sanitized and open defecation free village councils) in ten districts of Rajasthan, the largest State by area in India. Five key parameters of water safety were rapidly assessed utilizing household survey questionnaire, structured-observations, visual inspections and testing bacteriological quality of water. The results of the research reveal that three out of five key parameters scored between 50 and 60 percent and two parameters scored between 60 and 70 percent. The State water safety index is 60.26 percent. All the Nirmal Gram Panchayats in Rajasthan needs to develop and implement the water quality surveillance and monitoring plan of actions with the technical and financial support from the state water and sanitation mission and respective district water and sanitation missions to ensure hundred percent water safety in all the Nirmal Gram Panchayats. [ABSTRACT FROM AUTHOR]