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• Composition and antibiotic resistance of FCB were investigated in WWTP. • Sedimentary tank contributed most to the removal of FCB. • The dominant FCB belonged to Escherichia coli and Klebsiella pneumoniae. • Biological unit significantly increased antibiotic resistant rate of FCB community. • Health risk caused by Klebsiella pneumoniae should be emphasized after WWTP. The dynamics of the composition and antibiotic resistance of the fecal coliform bacteria (FCB) in a typical wastewater treatment plant (WWTP) were investigated concerning the seasonal changes. Results showed that WWTP could remove the FCB concentration by 3∼5 logs within the effluent of 104∼105 CFU/L, but the antibiotic resistant rate of FCB species increased significantly after WWTP. The dominant FCB changed from Escherichia coli in the influent (∼73.0%) to Klebsiella pneumoniae in the effluent (∼53.3%) after WWTP, where the Escherichia coli was removed the most, while Klebsiella pneumoniae was the most persistent. The secondary tank removed the most of FCB (by 3∼4 logs) compared to other processes, but increased all the concerned antibiotic resistant rate. The potential super bugs of FCB community showing resistance to all the target antibiotics were selected in the biological treatment unit of WWTP. The FCB showed the highest multiple antibiotic resistance (92.9%) in total which even increased to 100% in the effluent. Klebsiella has the highest antibiotic resistant rate in FCB, with a multiple antibiotic resistance rate of 98.4%. These indicated that the Klebsiella pneumoniae not just Escherichia coli should be specially emphasized after WWTP concerning the health risk associated with FCB community. [Display omitted] [ABSTRACT FROM AUTHOR]

• The indicator microorganisms increased along the water flow direction. • Indicator microorganisms had a positive correlation with COD. • Increased indicator microorganisms led to over 30% health risk increase. • Indicator microorganisms' concentration was higher in summer/autumn than in spring. • Staff related to water surface operation had the highest health risk. As an important means to solve water shortage, reclaimed water has been widely used for landscape water supply. However, with the emergence of large-scale epidemic diseases such as SARS, avian influenza and COVID-19 in recent years, people are increasingly concerned about the public health safety of reclaimed water discharged into landscape water, especially the pathogenic microorganisms in it. In this study, the water quality and microorganisms of the Old Summer Palace, a landscape water body with reclaimed water as the only replenishment water source, were tracked through long-term dynamic monitoring. And the health risks of indicator microorganisms were analyzed using Quantitative Microbial Risk Assessment (QMRA). It was found that the concentration of indicator microorganisms Enterococcus (ENT), Escherichia coli (EC) and Fecal coliform (FC) generally showed an upward trend along the direction of water flow and increased by more than 0.6 log at the end of the flow. The concentrations of indicator microorganisms were higher in summer and autumn than those in spring. And there was a positive correlation between the concentration of indicator microorganisms and COD. Further research suggested that increased concentration of indicator microorganisms also led to increased health risks, which were more than 30% higher in other areas of the park than the water inlet area and required special attention. In addition, (water) surface operation exposure pathway had much higher health risks than other pathways and people in related occupations were advised to take precautions to reduce the risks. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • Culturable enterococci decreased at the thermophilic phase of sludge compost. • The proportion of VBNC enterococci increased at the thermophilic phase. • Extending the cooling phase of sludge compost reduced VBNC enterococci ratio. • Antibiotic-resistant enterococci were residual in the compost product. • Sludge compost products should be considered as a significant reservoir for ARGs. Sludge composting is a sludge resource utilization method that can reduce pollutants, such as pathogens. Enterococci are regarded as more reliable and conservative indicators of pathogen inactivation than fecal coliforms, which are typically used as indicators of fecal pollution. Non-spore pathogenic bacteria may enter a viable but non-culturable (VBNC) state during composting, leading to residual risk. The VBNC status of bacteria is related to their survival during composting. However, the survival mechanisms of enterococci during sludge composting remain unclear. Therefore, this study aimed to investigate the VBNC state of enterococci in different phases of simulated sludge composting and the fate of antibiotic resistance genes (ARGs) and mobile genetic elements (MGEs) during the composting process. This study is expected to provide a basis for subsequent exploration of possible methods to completely inactivate enterococci and reduce ARGs during sludge composting. Culturable enterococci were reduced in the thermophilic phase of sludge composting, but the proportion of VBNC subpopulation increased. It was reported for the first time that most VBNC enterococci were killed by extending the cooling phase of sludge compost, and by prolonging the cooling phase the types of ARG were reduced. However, there was a certain quantity (approximately 104/g dry weight) of culturable and VBNC enterococci in the compost products. In addition, MGEs and ARGs exist in both bacteria and compost products, leading to the risk of spreading antibiotic-resistant bacteria and antibiotic resistance when sludge compost products are used. [ABSTRACT FROM AUTHOR]

Ropy defect of pasteurized fluid milk is a type of spoilage which manifests itself by an increased viscosity, slimy body, and string-like flow during pouring. This defect has, among other causes, been attributed to the growth, proliferation and exopolysaccharide production by coliform bacteria, which are most commonly introduced in milk as post-pasteurization contaminants. As we identified both Klebsiella pneumoniae ssp. pneumoniae and Rahnella inusitata that were linked to a ropy defect, the goal of this study was to characterize 3 K. pneumoniae ssp. pneumoniae strains and 2 R. inusitata for (1) their ability to grow and cause ropy defect in milk at 6°C and 21°C and to (2) probe the genetic basis for observed ropy phenotype. Although all K. pneumoniae ssp. pneumoniae and R. inusitata strains showed net growth of >4 log 10 over 48 h in UHT milk at 21°C, only R. inusitata strains displayed growth during 28-d incubation period at 6°C (>6 log 10). Two out of 3 K. pneumoniae ssp. pneumoniae strains were capable of causing the ropy defect in milk at 21°C, as supported by an increase in the viscosity of milk and string-like flow during pouring; these 2 strains were originally isolated from raw milk. Only one R. inusitata strains was able to cause the ropy defect in milk; this strain was able to cause the defect at both 6°C and 21°C, and was originally isolated from a pasteurized milk. These findings suggest that the potential of K. pneumoniae ssp. pneumoniae and R. inusitata to cause ropy defect in milk is a strain-dependent characteristic. Comparative genomics provided no definitive answer on genetic basis for the ropy phenotype. However, for K. pneumoniae ssp. pneumoniae, genes rffG, rffH, rfbD, and rfbC involved in biosynthesis and secretion of enterobacterial common antigen (ECA) could only be found in the 2 strains that produced ropy defect, and for R. inusitata a set of 2 glycosyltransferase- and flippase genes involved in nucleotide sugar biosynthesis and export could only be identified in the ropy strain. Although these results provide some initial information for potential markers for strains that can cause ropy milk, the relationship between genetic content and ropiness in milk remains poorly understood and merits further investigation. [ABSTRACT FROM AUTHOR]

Currently, more attention is being paid to new and innovative techniques for combating issues like the emergence of multidrug-resistant strains (MDRs), the proliferation of biofilms, and the failure of antibiotics. In order to combat this, scientists are nowadays exploring different activable and responsive materials. Nano-sized barium titanate is a material that has an excellent piezo-responsive nature. The synthesis of perovskite barium titanate (BTO) nanoparticles by a nonconventional solvothermal method with exceptional piezo and ferroelectric properties is reported in this work. The synthesized BTO nanoparticles were well-characterized using different tools such as XRD, FTIR, TGA, electron microscopy, and UV–Vis spectroscopy, and the microstructure was analyzed using theoretical Rietveld refinement studies to substantiate the proper formation of the BTO nanostructure. Two different phases of BTO nanoparticles are observed after the refinement. Then, the piezoelectric effectiveness was further estimated by theoretical density functional theory (DFT) calculation. The catalytic behavior of the nanoparticles in bacteria has been studied for the degradation of Gram-negative Escherichia coli and Gram-positive Enterococcus faecalis cells using an ultrasonically driven piezocatalytic effect. A promising value in bacterial eradication was depicted by the antibacterial efficacy observed herein, with a few minutes of soft ultrasound (15 kHz) generating an enormous number of reactive radicals (ROS). The result of this study could aid in generating new dimensions in antibacterial therapy. [ABSTRACT FROM AUTHOR]

For educators in particular, the implementation of online learning during the epidemic both potential and challenges. In order to correctly attain learning outcomes, creativity is required to ensure that online learning is effective and efficient. In order to get through those problems, having the necessary learning resources is undoubtedly highly beneficial. However, there are still few learning resources accessible in several competency areas, such as practical work in food safety. Food safety is a topic that students studying food packaging technology, culinary arts, catering, public health, and food technology must master. The goal of this research is to create a virtual food safety laboratory application that includes a coliform detection game. This game app is meant to aid in the process of learning about This research focuses on food security and uses the ADDIE (Analysis, Design, Development, Implementation, and Evaluation) model approach to implement the steps of the game development life cycle. The coliform detection game app was validated by two material specialists and two design and media experts. Application tests were conducted in groups of five individuals, involving 25 students in the third semester of the culinary arts program at Creative Media State Polytechnic. The average pre-test score obtained from these trials was 2.88, while the average post-test score at the same time was 9.28. The data clearly indicates that the coliform detection game application contributes to online learning as it significantly enhances student knowledge. [ABSTRACT FROM AUTHOR]

[Display omitted] • The three processes achieved hygienization of sludge, maintained after 72 h storage. • Salmonella was cultured only in PS and MAD; qPCR had negative results in all samples. • TP increased removal of total and viable E.coli in TAD but favored VBNC state. • PMA technique cannot fully discriminate viable from not viable bacteria in sludge. Sewage sludge should be stabilized for its beneficial use and pathogens, among other factors, should comply with environmental regulations. Three sludge stabilization process were compared to assess their suitability for producing Class A biosolids: MAD-AT (mesophilic (37 °C) anaerobic digestion (MAD) followed by an alkaline treatment (AT)); TAD (thermophilic (55 °C) anaerobic digester); and TP-TAD (mild thermal (80 °C, 1 h) pretreatment (TP) followed by a TAD). E. coli and Salmonella spp. were determined, differentiating three possible states: total cells (qPCR), viable cells using the propidium monoazide method (PMA-qPCR), and culturable cells (MPN). Culture techniques followed by the confirmative biochemical tests identified the presence of Salmonella spp. in PS and MAD samples, while the molecular methods (qPCR and PMA-qPCR) showed negative results in all samples. The TP + TAD arrangement reduced the concentration of total and viable E. coli cells in a greater extent than the TAD process. However, an increase of culturable E. coli was observed in the corresponding TAD step, indicating that the mild thermal pretreatment induced the viable but non-culturable state in E. coli. In addition, the PMA technique did not discriminate viable from non-viable bacteria in complex matrices. The three processes produced Class A biosolids (fecal coliforms < 1000 MPN/gTS and Salmonella spp, < 3 MPN/gTS) maintaining compliance after a 72 h storage period. It appears that the TP step favors the viable but not culturable state in E. coli cells, a finding that should be considered when adopting mild thermal treatment in sludge stabilization process arrangements. [ABSTRACT FROM AUTHOR]

This study explored the effects of H 2 O 2 on Cyanobacteria and non-target microbes using fluorometry, microscopy, flow cytometry, and high throughput DNA sequencing of the 16S rRNA gene during a series of mesocosm and whole-ecosystem experiments in a eutrophic pond in NY, USA. The addition of H 2 O 2 (8 mg/L) significantly reduced Cyanobacteria concentrations during a majority of experiments (66%; 6 of 9) and significantly increased eukaryotic green and unicellular brown algae in 78% and 45% of experiments, respectively. While heterotrophic bacteria declined significantly following H 2 O 2 addition in all experiments, bacteria indicative of potential fecal contamination (Escherichia coli, Enterococcus , fecal coliform bacteria) consistently and significantly increased in response to H 2 O 2 , evidencing a form of 'pollution swapping'. H 2 O 2 more effectively reduced Cyanobacteria in enclosed mesocosms compared to whole-ecosystem applications. Ten whole-pond H 2 O 2 applications over a two-year period temporarily reduced cyanobacterial levels but never reduced concentrations below bloom thresholds and populations always rebounded in two weeks or less. The bacterial phyla of Cyanobacteria, Actinobacteria, and Planctomycetes were the most negatively impacted by H 2 O 2. Microcystis was always reduced by H 2 O 2 , as was the toxin microcystin, but Microcystis remained dominant even after repeated H 2 O 2 treatments. Although H 2 O 2 favored the growth of eukaryotic algae over potentially harmful Cyanobacteria, the inability of H 2 O 2 to end cyanobacterial blooms in this eutrophic waterbody suggests it is a non-ideal mitigation approach in high biomass ecosystems and should be used judiciously due to potential negative impacts on non-target organisms and promotion of bacteria indicative of fecal contamination. [Display omitted] [ABSTRACT FROM AUTHOR]

• HPC22 was the most sensitive method to detect bacteria in drinking water. • ATP and ALP-2 methods were the most sensitive alternative (rapid) methods. • HPC22 and ATP detected a dilution of each contaminant source in drinking water. • ATP followed by ALP-2 are promising rapid methods to potentially replace HPC22. There is a risk of contamination by (pathogenic) microorganisms from the outside environment into the drinking water during maintenance or pipe breaches in the drinking water distribution system (DWDS) and, consequently, the drinking water distributed to consumers may result in possible detrimental effects on public health. Traditional time-consuming microbiological testing is, therefore, performed to confirm drinking water is not microbially contaminated. This is done by culturing methods of the faecal indicators Escherichia coli , intestinal enterococci and the technical parameters coliform bacteria and heterotrophic plate counts at 22 °C (HPC22). In this study, fast methods (adenosine triphosphate (ATP), flow cytometry, enzyme activity and qPCR) were compared as an alternative for HPC22. Using dilution series and field samples, ATP (ATP total-lab and ATP cell-mob) and enzymatic activity (ALP-2) methods proved to be the more reliable and sensitive than flow cytometry and qPCR methods for detecting microbiological contaminations in drinking water. Significant (p < 0.05) and relatively strong correlations (R2 = 0.61–0.76) were obtained between HPC22 and both ATP methods, enzyme activity and qPCR parameters, but relations with flow cytometry were weak (R2 = 0.24 – 0.52). The samples taken after repairs or a calamity from the DWDS showed in general limited variation in the HPC22 count and were in most cases below the guidance level of 1,000 CFU/mL. We recommend that the best performing alternative methods, i.e. ATP total-lab and ATP cell-mob and ALP-2, should be included next to HPC22 in additional field studies to further test and compare these methods to be able to decide which fast method can replace HPC22 analysis after maintenance work in the DWDS. [Display omitted] [ABSTRACT FROM AUTHOR]

Erzincan Tulum cheeses were produced from raw sheep milk with traditional homemade rennet as the uninoculated (control) and inoculated with Penicillium roqueforti 41. The cheese was ripened at 4 ± 1 °C for 120 days. All the cheese samples were drilled to achieve oxygenation during the last two stages of the ripening period. The microbiological and physicochemical properties, presence of mycotoxins and sensory characteristics of the Tulum cheeses, which were filled by pressing into the goat skin bags (called tulums) and plastic barrels, were investigated during the ripening period. The coliform bacteria count of the cheeses decreased, and Staphylococcus aureus was not detected (<2 log CFU/g) in the cheeses. The lowest and highest levels of penicillic acid (PA), roquefortine C and mycophenolic acid (MPA) in the cheeses during ripening ranged from 0.01 to 0.08, 0.01–0.06 and ND–0.06 mg/kg, respectively. Patulin was not detected. It was concluded that the Tulum cheeses were safer in terms of the amount of patulin, PA, roquefortine C, and MPA than those previously reported in the literature. P. roqueforti counts considerably increased during the last two stages of ripening. A new variety of credible mouldy cheese can be manufactured using the P. roqueforti 41 strain. However, a drilling process is needed to provide oxygen for P. roqueforti 41 growth during ripening. • Traditional rennet and Akkaraman sheep milk are used in Erzincan Tulum cheese production. • Erzincan Tulum cheese was produced with the P. roqueforti 41 strain. • MPA, penicillic acid, patulin, roquefortine C determined in Tulum cheese during ripening. • A new safe mouldy Tulum cheese was produced from the P. roqueforti 41 mould strain. • The drilling process provides oxygen for P. roqueforti 41 growth during ripening. [ABSTRACT FROM AUTHOR]

Wastewater recycling and reuse is very important, specially in countries with water shortage problem. Disinfection is very crucial step of wastewater treatment, particulary from the reuse and environmental protection point of view. In this research, the efficiency of the advanced oxidation process using UV and H 2 O 2 combination was investigated on fecal coliform (FC) inactivation from a real industrial effluent; furthermore, the optimal condition for disinfection of the effluent using various parameters such as pH, H 2 O 2 concentration, and contact time was determined. Based on the acquired outcomes, by pH decline from 11 to 7 and 3 inactivation rate increased (6.7% and 20.9%, sequentially), indicating the efficacy of acidic condition on the process. Increasing H 2 O 2 concentration from 5 mg/L to 15 mg/L, 25 mg/L, and 35 mg/L, was led to increase FC inactivation by 16.6%, 29.75%, and 36.33%, respectively. Considering contcat time impact on the process performance, our findings revealed that the best efficiency obtained after 40 (s) contact time. It can be concluded that the combined UV/H 2 O 2 is more potent than single UV and H 2 O 2 process, making it possible to reach irrigation standards. [Display omitted] • Novel laboratory setup built to measure the fecal coliform removal rate of effluent. • Effect of pH, H 2 O 2 concentration, retention time on fecal coliform removal studied. • The highest log. inactivation of 4.69 was reported for pH = 3. • The 36.33% increment was recorded for inactivation logarithm as the content of H 2 O 2 increased from 5 to 35 mg/L. • The acidic ambient required 40 s, the lowest retention time, for coliform removal. [ABSTRACT FROM AUTHOR]

Our objectives were to evaluate the diagnostic accuracy of a rapid and novel immunochromatography-based mastitis kit that includes 3 independent tests to detect coliforms (Escherichia coli or Klebsiella pneumoniae), Streptococcus spp., and Staphylococcus aureus. The kit was developed to facilitate diagnostic-based mastitis treatment. Validation of the kit was based on 154 aseptically collected mastitis samples from 2 clinical herds (clinical population) and 120 milk samples from 3 nonclinical herds (nonclinical population) without clinical cases at the time of enrollment. One herd sampled at different times was common to both populations. A 3-test in 2-population Bayesian latent class model with uniform priors for all test parameters except specificity of culture, which was modeled informatively, was used to estimate sensitivity (Se) and specificity (Sp) of the test kit, culture, and PCR at the cow level. The mastitis test kit's 96.9% Sp for Streptococcus spp. had a low false positive percentage (3.1%), which, together with the kit's rapid turnaround time for results, makes it a suitable initial screening test that producers can use to identify clinical cows to treat based on Streptococcus spp. mastitis in kit-positive results. Due to the 60.4% kit Se, producers should follow up on Streptococcus spp. kit-negative cows using a confirmatory test such as PCR (Sp of 98.4%) or culture (Sp of 99.6%). In contrast, aerobic culture had Se of 76.5% and Sp of 99.6% for Streptococcus spp. Similarly, the Sp of the kit (98.2%) and culture (99.8%) for Staph. aureus were particularly high, and even though the kit's Se (61.0%) was lower than culture (88.4%; posterior probability of difference 98%), the kit could be beneficial before use of a confirmatory test for kit-negative samples due to its ease and rapid turnaround time. Mostly, quantitative real-time (q)PCR outperformed the kit's Se (37.7%) and Sp (92.9%) for coliforms, as well as the kit's Se (60.4%) for Streptococcus spp. However, qPCR may require more technical skills and turnaround time for final results. Use of the on-farm mastitis test kit evaluated in the present study could enhance sustainable antimicrobial drug use by rapidly identifying Streptococcus mastitis for targeted treatment. Furthermore, the kit may be used in a Staph. aureus outbreak where cows can be rapidly screened to identify cases for segregation or culling during an outbreak and kit-negative cows further confirmed by milk culture or qPCR. However, the cost-effectiveness of such an approach has not been investigated. [ABSTRACT FROM AUTHOR]

Achieving universal access to clean water, as mandated by SDG 6 – Clean Water and Sanitation, is crucial for supporting human health and environmental sustainability. Water treatment plants generate a by-product known as Water Treatment Plant Sludge (WTPS), comprising organic and inorganic substances. Traditionally, the disposal of WTPS poses environmental risks, including nutrient runoff and heavy metal contamination. This study investigates using centrifuged WTPS, without prior treatment, as an adsorbent to remove contaminants from treated wastewater, offering a sustainable waste management solution. Through comprehensive characterization using Scanning Electron Microscopy, Thermogravimetric Analysis, Fourier Transform Infrared Spectroscopy, and geo-environmental parameter assessment, the research evaluates the adsorption efficacy of WTPS. A factorial design methodology facilitated the systematic examination of adsorption tests. Findings indicate that WTPS exhibits adsorption capacities for phosphorus (q = 0.2 mg g-1), Chemical Oxygen Demand (q = 1.1 mg g-1), and metals under specific conditions. Maximum removal efficiencies for total coliforms and Escherichia coli were achieved with extended contact times, showcasing WTPS's potential as a robust adsorbent. The research demonstrates that centrifuged WTPS can significantly reduce concentrations of metals such as Pb, Co, and Ni (100%), Al (96%), Cu (95%), and Fe (93%) in treated wastewater, presenting a promising approach for enhancing wastewater quality. However, the interaction between WTPS and wastewater resulted in an increased concentration of Mn in the effluent, highlighting the complex dynamics of adsorption processes. In conclusion, centrifuged WTPS emerges as a viable, cost-effective adsorbent, aligning with sustainable waste management practices and circular economy principles. [ABSTRACT FROM AUTHOR]

Various pathogenic microorganisms present in municipal solid waste (MSW) can pose significant hazards to both the environment and public health. Spraying Slightly Acidic Electrolyzed Water (SAEW) is an effective method for decontaminating microorganisms in the air and on surfaces in the waste sorting rooms. SAEW treatment, with an effective chlorine concentration (ECC) of 28.4–44.5 mg/L and a pH range of 5.0–6.5, was conducted in the waste sorting rooms of the old, high-rise, and villa residential communities in Shanghai, China. The efficacy of SAEW treatment was assessed by examining the microbial population in the air, on waste containers, on sanitation workers' hands, and the microbial community structure of MSW samples. SAEW treatment resulted in the total bacterial reduction ranging from 0.07 to 1.70 log 10 colony-forming units (CFU)/cm2 on waste containers, with corresponding reduction efficiencies between 15.7% and 98.0%. Additionally, the positive rates of coliforms were decreased by 18.7%–95.2%. Furthermore, the application of SAEW demonstrated a significant impact on reducing airborne bacterial and fungal levels. SAEW was proven effective on object surfaces, in the air and on human skin, achieving disinfection efficiencies ranging from 22.7% to 54.3% on sanitation workers' hands. And the most significant inhibition of microbial growth was observed in the waste sorting room of the villa residential community. The microbial diversity and structure of MSW samples exhibited noticeable differences before and after the SAEW application. These findings suggest that SAEW holds significant potential as an ideal, environmentally friendly broad-spectrum disinfectant for preventing and controlling microbial contamination in the waste sorting rooms. [Display omitted] • Microbial contamination was reduced with SAEW in waste sorting rooms. • SAEW was proven effective on object surfaces, in the air and on human skin. • SAEW changed the microbial diversity and structure of MSW samples. • The bacterial reduction efficiencies of SAEW on waste containers were 15.7%–98.0%. [ABSTRACT FROM AUTHOR]

• A validated RT-PCR method targeting 16S ribosomal RNA to qualitatively E. coli in drinking water at a sensitivity of 1 CFU/100 ml. • The method is as sensitive as the reference culture method. • The E. coli RT-PCR showed high interlaboratory reproducibility. • An extensive comparison on practical samples showed good agreement between RT-PCR and the culture method. • Application of the RT-PCR will improve the safety of drinking water consumers. Escherichia coli (E. coli) plays a central role as an indicator for fecal contamination to predict the possible presence of microbial pathogens in drinking water. Current detection methods for E. coli are based on time-consuming culture-based techniques. There is a strong need for methods to detect fecal contamination rapidly in distributed drinking water to prevent outbreaks of waterborne disease and support water utilities to efficiently manage their operations like actions to repair or maintain distribution pipes, to minimize impact on consumers. This study describes the validation and application of a qualitative real time reverse transcription PCR (RT-PCR) method targeting 16S ribosomal RNA (rRNA) for rapid detection of E. coli in distributed drinking water. The RT-PCR assay targets 16S rRNA, a highly abundant RNA in viable cells, enabling robust detection at the required sensitivity of 1 CFU/100 ml. The validation was performed by comparing the RT-PCR method with the culture-based chromogenic reference method (CCA) using the protocol and criteria described in ISO 16,140–2:2016. The validation demonstrated that this RT-PCR method can be used to specifically detect E. coli in a broad range of drinking water samples with at least the same limit of detection as the culture method (Relative Limit Of Detection = 0.75, range 0.43–1.43). The inclusivity study showed that the RT-PCR method was able to detect a broad range of E. coli strains derived from different sources and geographic areas, including pathogenic serotype O157 strains that are not detected with the culture method. The exclusivity study determined that other bacterial genera are not detected with this RT-PCR. However, Escherichia fergusonii was detected and, based on " in silico " analysis, it is expected that also E. albertii and E. marmotae and Shigella species will be detectable using this RT-PCR. An interlaboratory study confirmed that the RT-PCR and culture method have comparable sensitivities when tested by different participants at different laboratories. The application of RT-PCR to confirm the hygienic quality of distributed drinking water after actions to repair or maintain distribution pipes was compared with the culture method on 8076 routine samples, analyzed by the drinking water laboratories in the Netherlands. This comparison study showed a 96.4 % agreement between RT-PCR and culture. In 3.3 % of the samples E. coli was detected with RT-PCR and not with the culture method and in 0.1 % of the samples E. coli was only detected by culture confirming either a higher sensitivity for RT-PCR or the detection of RNA from uncultivable cells. Finally, the application of RT-PCR was highlighted during a contamination event in Belgium where we demonstrate the potency of RT-PCR as a tool to rapidly monitor the spread of microbial contamination and to monitor the effect of measures to remove the contamination This is the first fully validated rapid nucleic based method for detection of E. coli in distributed drinking water. These results demonstrate that this RT-PCR method can be used as a rapid alternative to the culture method to monitor E. coli in distributed drinking water. However, it should be emphasized that nucleic acid based detection methods rely on highly different detection principles (detection of captured nucleic acids present in a sample) than culture base methods (presence of cells cultivable on a selective medium) resulting in occasional different analysis results. Varying treatment and disinfection steps (UV, chlorine, monochloramine, Ozone) or environmental factors (decay) can influence the results and cause differences between RT-PCR and culture methods. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • An integrated model predicted pollution changes and assessed the risks of E. coli. • The pollution levels in the tributary basin surpassed those in the mainstream basin. • Three exposure pathways exceeded the acceptable risk level recommended by the WHO. • Strategies for point pollution were more effective in reducing disease burdens. Escherichia coli (E. coli), a typical fecal coliform, can enter surface rivers through daily wastewater and septic effluents, as well as the use of fecal fertilizers. Pathogenic strains of E. coli pose a significant public health risk. Despite China's rapid economic and social development, sanitation and watershed management still face challenges. In this study, we employ a combined model of the Soil and Water Assessment Tool and Quantitative Microbial Risk Assessment to predict pollution changes, considering social development and climate change. Our aim is to quantify the risks and assess pollution prevention strategies for E. coli in the Three Gorges Reservoir (TGR) region. The results indicated that under moderate development, the average E. coli concentrations and disease burdens were 367 ± 75 CFU/100 mL and 23.4 (95 % Confidence Interval (CI): 2.8–72.6) Disability-Adjusted Life Years (DALYs, per 1,000,000 population per year), respectively. Under rapid development, these values were 330 ± 58 CFU/100 mL and 21.2 (95 % CI: 2.6–65.1) DALYs, respectively. Implementing a point strategy, mainly increasing sewage collection rates, could reduce E. coli concentrations by approximately 30 % and disease burdens by 27–28 %. For a diffuse strategy, primarily extending composting duration, reductions of 9 % in E. coli concentrations and 7–8 % in disease burdens were observed. Combining both strategies resulted in a 40 % decrease in E. coli concentrations and 35–36 % reduction in disease burdens. This model, incorporating social development, climate change, and microbial risk, provides insights into predicting pollution changes and evaluating the effectiveness of prevention strategies for E. coli in the TGR region and similar watersheds. [ABSTRACT FROM AUTHOR]

This study aimed to provide a critical analysis of official data obtained by Instituto Mineiro de Agropecuária (IMA) regarding the compliance with minimum ripening time (MRT) and moisture criteria defined by the Minas Gerais state, Brazil, for Minas Artisanal Cheese (in Portuguese: Queijo Minas Artesanal, QMA), and how these parameters can influence the counts of hygiene indicator microorganisms. QMA samples collected between January 2010 to May 2023 (n = 1803) were analyzed. Few non-compliant samples were identified due to the denaturation of alkaline phosphatase and presence of starch. High relative frequencies of non-compliance with MRT were identified in QMA samples from producer regions of Cerrado, Serra do Salitre, Araxá and Serro (88.5%, 66.7%, 63.4% and 62.2%, respectively), and high relative frequencies of non-compliance to moisture were identified in QMA samples from Serro, Serra do Salitre and Cerrado (36.5%, 29.0% and 24.4%, respectively). Counts of total coliforms, Escherichia coli and coagulase positive staphylococci were significantly higher (p < 0.0001) in samples in non-compliance to the MRT and moisture content; when these data were analyzed per producing region, this trend was observed only for QMA produced in Serro. The lack of data regarding ripening time hampered a more precise analysis over the years, as this information was absent for all QMA samples collected and processed since 2022 (n = 150): such information should be systematically recorded during QMA sampling for surveillance programs, due to its relevance for identity, quality and safety. Our data also indicate the need to implement educational programs to improve the adequacy of QMA to official criteria. • High relative frequencies of cheese samples non-compliant with ripening time and moisture. • Counts of hygiene indicators were significantly higher in samples non-compliant to ripening time and moisture. • Educational programs are need to improve cheese adequacy to official criteria. [ABSTRACT FROM AUTHOR]

Over the period 2016–2022 environmental data were obtained at four points in the northern section of the tropical Estero Salado (ES), the inner coastal lagoon that flows through Guayaquil, the largest city in Ecuador. Surface water from the more remote southern limit of the ES, El Morro was also sampled in 2022. The study shows that waters of the northern part of this low salinity (<12) coastal lagoon were often hypoxic, occasionally approached anoxia, and were slightly acidic (6.86 ± 0.67). The same waters contained extremely high concentrations of dissolved inorganic nitrogen which averaged between 2.00 and 16.3 μM for nitrite, 89.8–238 μM for nitrate and 35.0–758 μM for ammonium whilst dissolved inorganic phosphorus averaged 21.3–381 μM. Dissolved oxygen was between 22.4 and 129 μM, and all samples were <50% saturated. Additionally, remarkably high concentrations of total and fecal coliforms and Escherichia coli were measured in this northern section, which are well above national and international standards. A trophic state index strongly indicates that northern part of the ES is hyper-eutrophic. Whilst nutrients were at lower concentrations at El Morro, they still exceeded those expected for typical natural and balanced estuaries, thus showing signs of eutrophication. Two major drivers for these hyper-eutrophic conditions in the north are effectively no riverine inputs to flush the system, and nutrient inputs being dominated by run off from the city as industrial, wastewater and sewage discharges, together with pulses associated with the seasonal rainfall. Based on comparison of nutrient data given here with the same parameters from several decades ago, the situation has become worse over this timescale. This trend follows the dramatic increase in population of the city of Guayaquil, and associated increase in discharges of polluted waters. The ES needs major improvements in environmental quality if it is to avoid further deleterious impacts for local populations. The ES thus fits into the global trend of increasing eutrophication in estuarine and coastal waters. Estimates using the new nutrient measurements indicate that the ES is exporting significant amounts of DIN and DIP into coastal waters of the Gulf of Guayaquil and then the Eastern South Pacific. [Display omitted] • Estero Salado (Guayaquil, Ecuador) is hyper-eutrophic, sub-oxic or anoxic and high fecal bacteria loads. • It follows global trends of increasing eutrophication in nearshore waters. • Nutrient concentrations have increased, mirroring an increasing population. • New data improve our knowledge of eutrophication in the western seaboard of S. America. • The ES could input significant amounts of DIN and DIP to the Eastern South Pacific. [ABSTRACT FROM AUTHOR]

• Cinnamaldehyde-nanostructured lipid carriers and nanoemulsion reduced nitrite in sausage. • Nanoemulsion and NE + nitrite indicated the lowest oxidative and microbial features. • CA/NLC/NE + nitrite indicated better color quality and higher oxymyoglobin content. • NE and NLC (+nitrite) were favored by the panelists in terms of color and flavor. This study aimed to produce cinnamaldehyde (CA)-loaded nanostructured lipid carriers (NLC) and nanoemulsion (NE) to replace nitrite in sausage. The NLC and NE droplet sizes were 132 and 116 nm with encapsulation efficiency of 98 and 96 %, respectively. In in vitro antimicrobial assessment, the free CA and NE showed higher microbial activity against S. aureus and E. coli than NLC. Meanwhile, NE showed a faster release profile for CA than NLC. Among the samples, NE and NE + nitrite indicated the lowest peroxide value (3.7 ± 0.1), TVBN amount (8.6 ± 0.2), acidity (0.3 ± 0.02), microbial quality (against E. coli , C. perfringens , lactic acid bacteria, psychrophilic bacteria, total mold and yeast, and total viable counts), and sensory attribute, while the NE + nitrite sample exhibited better color properties and higher oxymyoglobin content (5–10 % higher). Therefore, NE + nitrite can be the best choice due to supporting the different quality parameters of sausage. [ABSTRACT FROM AUTHOR]

Earthworms play a pivotal role in the elimination of fecal coliforms during vermicomposting of fruit and vegetable waste (FVWs). However, the specific mechanisms underlying the action of earthworm mucus remain unclear. This study investigated the mechanisms of fecal coliform reduction related to earthworm mucus during FVWs vermicomposting by comparing treatments with and without earthworms. The results show that the secretion of earthworm mucus decreased by 13.93 % during the startup phase, but significantly (P < 0.001) increased by 57.80 % during the degradation phase. Compared to the control without earthworms, vermicomposting led to a significant (P < 0.05) 1.22 −fold increase in the population of active bacteria, with a strong positive correlation between mucus characteristics and dominant bacterial phyla. As the dominant fecal coliforms, Escherichia coli and Klebsiella pneumoniae significantly (P < 0.05) declined by 86.20 % and 93.38 %, respectively, in the vermi-reactor relative to the control. Bacterial dispersal limitation served as a key factor constraining the elimination of E. coli (r = 0.73, P < 0.01) and K. pneumoniae (r = 0.77, P < 0.001) during vermicomposting. This study suggests that earthworm mucus increases the active bacterial abundance and cooperation by weakening the bacterial dispersal limitation, thus intensifying competition and antagonism between fecal coliforms and other bacteria. [Display omitted] • Significant correlation was observed between earthworm mucus and vermicomposting. • Deterministic process dominated in the community assembly during vermicomposting. • Dispersal limitation constrained the reduction of fecal coliforms. • Earthworm mucus promoted the growth and cooperation of active bacteria. • Earthworm mucus mainly mediated E. coli elimination rather than K. pneumoniae. [ABSTRACT FROM AUTHOR]

Regular testing of coastal waters for fecal coliform bacteria by shellfish sanitation programs could provide data to fill large gaps in existing coastal water quality monitoring, but research is needed to understand the opportunities and limitations of using these data for inference of long-term trends. In this study, we analyzed spatiotemporal trends from multidecadal fecal coliform concentration observations collected by a shellfish sanitation program, and assessed the feasibility of using these monitoring data to infer long-term water quality dynamics. We evaluated trends in fecal coliform concentrations for a 20-year period (1999–2021) using data collected from spatially fixed sampling sites (n = 466) in North Carolina (USA). Findings indicated that shellfish sanitation data can be used for long-term water quality inference under relatively stationary management conditions, and that salinity trends can be used to investigate management-driven bias in fecal coliform observations collected in a particular area. • 20-years of fecal coliform (FC) concentrations at 466 estuarine sites were analyzed. • 69 sites had significantly increasing or decreasing FC concentration trends. • FC and salinity trends were inversely correlated (r = −0.3). • Despite sampling bias, FC data from shellfish sanitation programs offer insights. [ABSTRACT FROM AUTHOR]

[Display omitted] • Minimizing the public health threat is important in sustainable use of MSW compost. • QMRA could predict risks of infection associated with application of MSW compost. • Indicator microorganisms could not adequately reflect the absence of pathogens. • The annual infection risk associated with ingestion of MSW compost was not acceptable. • All risks were decreased with increasing waiting time to near insignificant levels. Land application of MSW compost promotes the soil fertility and productivity, but there is concern about its chemical and microbial quality. Although, current microbial indicators of MSW compost are generally considered to be protective of human health, the use of these indicators doesn't adequately represent the presence of pathogens that might be more resistant to inactivation during composting process. This work aims evaluation of the microbial characteristics of MSW compost and estimation of the health risks associated with exposure to pathogens of potential concern in MSW compost. Although the recommended standards for fecal coliforms and Salmonella were met in a relatively high percentage of samples, there were detectable levels of microbial pathogens. The highest daily infection risk was estimated for Cryptosporidium (1.25 × 10−3 per person) followed by Salmonella and Campylobacter, while the lowest related to adenovirus. Infection risks were low for both farmers and children in one-time exposure and all pathogen risks were decreased with increasing waiting time to near insignificant levels. However, the median annual risk of cryptosporidiosis or gastroenteritis was above the recommended value of 10−3 per person per year. Because of potential presence of pathogens in MSW compost, some level of pathogen monitoring beyond conventional indicators may be required to estimate potential risks. The findings of this study could provide information to governments and local authorities in making decisions on measures to reduce risk from application of MSW compost. Further research is needed to obtain the reliable information about the inactivation of microorganisms in environment. [ABSTRACT FROM AUTHOR]

[Display omitted] • Characterizing leachate helps anticipate seasonal changes and challenges. • TKN, ammonia, BOD and TP removals improved at volumetric leachate ratios ≤0.02%. • At high hydraulic loading, most removals experienced a decrease except for ammonia. • Leachate COD, TKN and VLR% impacted nitrite, UVT% and removal rates. • Leachate chloride, arsenic, F1 and F2 negatively impacted TKN and BOD removal. The objective of this study was to evaluate the impacts of leachate co-treatment on a full-scale municipal WWTP by comparing plant performance at varying levels of leachate contributions and hydraulic loadings. Leachate BOD:COD ratio was 0.08 ± 0.07 and indicated a stabilized, old matrix and concentrations of zinc, iron, aluminum, chloride and sulfate were 0.174, 38, 1.47, 1803 and 119.1 mg/L, respectively. The average volumetric leachate ratio (VLR%) was approximately 0.01% corresponding to a daily volume of 30 m3 but reaching a maximum of 270 m3 (VLR% = 0.1%) and fluctuating on a daily-basis. A cluster analysis revealed 5 VLR% groupings that were used for subsequent analyses: no leachate, 0 < Low ≤ 0.001, 0.001 < Medium ≤ 0.02, 0.02 < High ≤ 0.05, 0.05 < Very high ≤ 0.2. Treated effluent concentrations of TKN, ammonia, fecal coliforms (FC), E. coli (EC), TSS and TP experienced a trend where effluent quality was improved at low and medium VLR% compared to no leachate addition, but deteriorated in high and very high VLR%. Treated effluent UVT% and EC were not statistically significantly different at varying VLR%, but FC was. Plant hydraulic had a significant impact on removal rates. Ammonia removals and nitrite concentrations improved in high flow conditions, while TP, BOD and cBOD removals deteriorated. Finally, VLR%, leachate COD, TKN ammonia, chloride and arsenic had significant relationships with plant performance. Thus, for leachate with comparable age and strength, VLR% should not exceed low to medium contributions (0 and 0.02%) during co-treatment at this WWTP. [ABSTRACT FROM AUTHOR]

The objective of this study was to perform a quantitative and qualitative evaluation of microbial contamination of harvested colostrum on 39 Czech dairy farms. The study identified the proportion of colostrum samples that met the recommended goals for total plate count (TPC), total coliform count (TCC), and gram-negative noncoliform count (NCC), and evaluated the effect of the farm, breed, parity, season of the year, time of calving, and colostrum volume on these 3 microbiological parameters. Colostrum samples from cows (n = 1,241; 57.6% from Czech Fleckvieh, and 42.4% from Holstein breed) were collected on dairy farms between autumn of 2015 and spring of 2017. The samples were collected after the first milking directly from milking buckets. In 155 out of 1,241 colostrum samples (26 farms, 6 samples each, except 1 farm), the species of microorganisms obtained by culture were determined, and the findings were classified into 4 groups according to the probable source of contamination as follows: (1) normal inhabitants of bovine skin and mucosa, (2) fecal contaminants, (3) environmental contaminants, and (4) potential gram-positive mammary pathogens. Our results showed heavy microbial contamination of collected colostrum samples (TPC median = 408,000 cfu/mL; TCC median = 200 cfu/mL; NCC median = 80 cfu/mL). Only 28.4% of samples met the requirement for TPC (<100,000 cfu/mL), 88.2% for TCC (<10,000 cfu/mL), and 86.0% for NCC (<5,000 cfu/mL). Among the tested factors, we found that farm had a significant effect on all 3 microbiological parameters, volume of colostrum had an effect on TPC (the highest TPC in <3.0 L of colostrum), and season had an effect on TCC and NCC (higher TCC in summer than in autumn and winter; the highest NCC in summer and higher in autumn than in spring and winter). Our results showed that most microbes isolated from colostrum belonged to normal inhabitants of bovine skin and mucosa, fecal, or environmental contaminants (i.e., 82.6%, 81.9%, and 75.5% of colostrum samples, respectively). Potential gram-positive mammary pathogens were found in 13.5% of samples. Escherichia coli was isolated from 9.0% of colostrum samples, and Streptococcus uberis and Streptococcus parauberis were each isolated from 5.2% of samples. Our study showed high microbial contamination of colostrum collected on dairy farms. Therefore, better hygiene and sanitation around colostrum harvest should be addressed by farmers. [ABSTRACT FROM AUTHOR]

The detection of coliforms in young cheese is a potential indication of undesirable microbial growth within the processing environment. The aim of this study was to investigate sources and conditions that lead to the intermittent detection of coliforms (1–3 log cfu/g) in young Cheddar cheese at a single commercial facility. Analysis of historical production data, in combination with iterative investigative sampling events, was performed to determine coliform levels in milk, whey, curd, and surfaces at the beginning, middle, and end of the production day. After sanitation, conveyor belt pieces from the draining and matting conveyor (DMC) were collected and evaluated for bacterial survivors using culture-based methods and scanning electron microscopy. Production data analysis indicated that cheese produced later in the production day (≥16 h) was significantly more likely to test positive for coliforms than cheese made earlier in the production day (<12 h). Enumeration of coliforms in raw and heat-treated milk demonstrated that the subpasteurization thermal treatment (67–70°C, 26–28 s) was effective at reducing, but not eliminating, coliforms. Repeated sampling identified the DMC, particularly the drain belt and belt 1, as a critical area that supported coliform growth during the production day. Coliform levels in whey entering the weir maintained a level of <1 cfu/mL throughout production; however, coliform levels in whey below the drain belt increased from <1 cfu/mL at midday (8 h) to 5.04 log cfu/mL by the end of the production day (~18 h). Routine sanitation inside the DMC resulted in undetectable coliform levels on easily accessible surfaces. However, enrichment and scanning electron microscopy of belt sections revealed pockets of viable coliforms and other bacteria in cracks and defects in conveyor belts, indicating that sanitation did not eliminate all viable bacteria. Low levels of coliforms are present in heat-treated milk and survive sanitation in the DMC and could serve as the initial seed for high levels of coliforms at the end of the production day. [ABSTRACT FROM AUTHOR]

Commercial Cheddar cheese production uses an automated, continuous production system that provides favorable conditions for specific undesirable bacterial subpopulations in certain sections of the processing system. The draining and matting conveyor (DMC) is a large, fully enclosed series of conveyor belts that separates curd and whey on the first drain belt and supports the cheddaring process in subsequent sections. In a previous study, we demonstrated that coliforms increase in the draining section of the DMC (pH 6.0–6.3, 36°C) over a typical 18-h production shift and can lead to detectable coliforms in finished cheese. Sampling at the commercial plant indicated 2 sources of very low levels of coliforms: (1) subpasteurized whey and curd entering the DMC and (2) surfaces in the DMC after sanitation. Mitigation of these sources would require different approaches. The aim of this study was to investigate whether naturally low levels of coliforms in whey could increase in the bulk liquid and attach to different surface materials within 18 h. A laboratory-scale system was created to mimic the conditions of the initial draining section of the DMC and consisted of single-pass, naturally contaminated whey (pH 6.3, 35°C) flowing through a bioreactor (1.11 L/h) containing coupons of surface types found in the DMC (stainless steel and polypropylene). Whey inside the bioreactor chamber and surface coupons were enumerated for bacterial subpopulations on selective media for planktonic and attached bacteria, respectively, at 0, 12, 15, and 18 h. Bacterial isolates were identified by 16S rDNA sequencing. Nonstarter bacteria present in the whey at 0 h included coliforms (Enterobacter), Pseudomonas , and Acinetobacter (0.80, 2.55, and 2.32 log cfu/mL, respectively), with each increasing significantly in whey (6.18, 7.00, and 5.89 log cfu/mL) and on coupons (5.20, 6.85, and 5.29 log cfu/cm2, respectively) after 18 h in the continuous flowing system. Scanning electron microscopy confirmed bacterial attachment on both surfaces, with early biofilm development evident on polypropylene coupons by 18 h. Results from this laboratory-scale study demonstrated that naturally low levels of coliforms entering the DMC in the whey could replicate within the conditions of the draining section of the DMC to the levels found in the commercial production environment. [ABSTRACT FROM AUTHOR]

Landfill is a huge pathogen reservoir and needs special attention. Herein, the distribution and spread risk of pathogen were assessed in excavated landfill scenario. The results show that landfill excavation will greatly increase the risk of environmental microbial contamination. The highest total concentration of culturable bacteria among landfill refuse, topsoil and plant leaves was found to be as high as 1010 CFU g−1. Total coliforms , Hemolytic bacteria , Staphylococcus aureus , Salmonella , Enterococci , and Fecal coliforms were detected in the landfill surrounding environment. Notably, pathogens were more likely to adhere to plant leaves, making it an important source of secondary pathogens. The culturable bacteria concentration in the air samples differed with the landfill zone with different operation status, and the highest culturable bacteria concentration was found in the excavated area of the landfill (3.3 × 104 CFU m−3), which was the main source of bioaerosol release. The distribution of bioaerosols in the downwind outside of the landfill showed a tendency of increasing and then decreasing, and the highest concentration of bioaerosols outside of the landfill (6.56 × 104 CFU m−3) was significantly higher than that in the excavated area of the landfill. The risk of respiratory inhalation was the main pathway leading to infection, whereas the HQ in (population inhalation hazardous quotient) at 500 m downwind the excavation landfill was still higher than 1, indicating that the neighboring residents were exposed to airborne microbial pollutants. The results of the study provide evidence for bioaerosols control protective measures taken to reduce health risk from the excavated landfill. [Display omitted] • Microbe from landfill are more likely to attach to wood, paper, and plastic. • Landfill surrounding plants are greater barrier for microbial containment. • Excavation process will increase the emission of microbial. • Aerosol dispersion model shows effectively simulation results. [ABSTRACT FROM AUTHOR]

The presence of micropollutants and pathogens in sanitary wastewater and surface water is a growing concern that impacts public health, environmental balance and the maintenance of water supply services. To improve sanitary wastewater treatment, it is necessary to develop and improve sustainable technologies. Among the available options, microalgae-based systems stand out for their efficiency and generation of value-added byproducts. To study the impact of luminosity and the presence of micropollutants (13 selected) on the removal of E. coli and total coliforms from real anaerobically treated wastewater, a pilot flat-panel photobioreactor (50 L) was operated in batch mode in a tropical climate region. This is the first study to evaluate whether micropollutants interfere with coliform groups, considering a microalgae-based system and an experiment in a tropical climate region. E. coli had better removal (from 104 to 101 CFU 100 mL−1) than did total coliforms (from 104 to 103 CFU 100 mL−1). The removal of E. coli was more strongly linked to luminosity and temperature, while the removal of total coliforms was influenced by the presence of the selected micropollutants. [Display omitted] • Removal of E. coli was higher than total coliforms, even with micropollutants. • Micropollutants presence influence the removals of total coliforms and of E. coli. • Changes in the luminosity doesn't affect the total coliforms and E. coli removals. • Multiple factors are significantly correlated with the TC and EC removals. [ABSTRACT FROM AUTHOR]

Romaine lettuce in the U.S. is primarily grown in California or Arizona and either processed near the growing regions (source processing) or transported long distance for processing in facilities serving distant markets (forward processing). Recurring outbreaks of Escherichia coli O157:H7 implicating romaine lettuce in recent years, which sometimes exhibited patterns of case clustering in Northeast and Midwest, have raised industry concerns over the potential impact of forward processing on romaine lettuce food safety and quality. In this study, freshly harvested romaine lettuce from a commercial field destined for both forward and source processing channels was tracked from farm to processing facility in two separate trials. Whole-head romaine lettuce and packaged fresh-cut products were collected from both forward and source facilities for microbiological and product quality analyses. High-throughput amplicon sequencing targeting16S rRNA gene was performed to describe shifts in lettuce microbiota. Total aerobic bacteria and coliform counts on whole-head lettuce and on fresh-cut lettuce at different storage times were significantly (p < 0.05) higher for those from the forward processing facility than those from the source processing facility. Microbiota on whole-head lettuce and on fresh-cut lettuce showed differential shifting after lettuce being subjected to source or forward processing, and after product storage. Consistent with the length of pre-processing delays between harvest and processing, the lettuce quality scores of source-processed romaine lettuce, especially at late stages of 2-week storage, was significantly higher than of forward-processed product (p < 0.05). • Romaine lettuce from local (source) and remote (forward) processing chains were tracked and tested. • Forward-processed lettuce had higher microbial loads than source-processed product. • Quality score of fresh-cut lettuce in cold storage declined with delayed processing. • A shift in microbiota was detected between source and forward-processed lettuce. [ABSTRACT FROM AUTHOR]

Escherichia coli are widely used by water quality managers as Fecal Indicator Bacteria, but current quantification methods do not differentiate them from benign, environmental Escherichia species such as E. marmotae (formerly named cryptic clade V) or E. ruysiae (cryptic clades III and IV). Reliable and specific techniques for their identification are required to avoid confounding microbial water quality assessments. To address this, a multiplex droplet digital PCR (ddPCR) assay targeting lipB (E. coli and E. ruysiae) and bglC (E. marmotae) was designed. The ddPCR performance was assessed using in silico analysis; genomic DNA from 40 local, international, and reference strains of target and non-target coliforms; and spiked water samples in a range relevant to water quality managers (1 to 1000 cells/100 mL). Results were compared to an analogous quantitative PCR (qPCR) and the Colilert method. Both PCR assays showed excellent sensitivity with a limit of detection of 0.05 pg/μL and 0.005 pg/μl for ddPCR and qPCR respectively, and of quantification of 0.5 pg/μL of genomic DNA. The ddPCR allowed differentiation and quantification of three Escherichia species per run by amplitude multiplexing and showed a high concordance with concentrations measured by Colilert once proportional bias was accounted for. In silico specificity testing underlined the possibility to further detect and distinguish Escherichia cryptic clade VI. Finally, the applicability of the ddPCR was successfully tested on environmental water samples where E. marmotae and E. ruysiae potentially confound E. coli counts based on the Most Probable Number method, highlighting the utility of this novel ddPCR as an efficient and rapid discriminatory test to improve water quality assessments. [Display omitted] • Novel droplet digital PCR assay for environmental DNA applications • Ability to differentiate and quantify E. coli and cryptic clades in a single run • Specific quantitation of fecal E. coli in water with high sensitivity and precision • Reduced turnaround time for in-depth microbial water quality assessments [ABSTRACT FROM AUTHOR]

• Physicochemical analysis revealed stable anaerobic digestion in varying seasons. • Total bacteria and coliform counts decreased significantly during anaerobic digestion. • Biofilm-forming capacity was observed in a majority of isolated strains. • Seasonal variations affected antimicrobial resistance in isolated strains. • Biofertilizers harbored multidrug-resistant strains, posing potential risks to public health. Samples from a dairy cattle waste-fed anaerobic digester were collected across seasons to assess sanitary safety for biofertilizer use. Isolated enterobacteria (suggestive of Escherichia coli) were tested for susceptibility to biocides, antimicrobials, and biofilm-forming capability. Results revealed a decrease in total bacteria, coliforms, and enterobacteria in biofertilizer compared to the effluent. Among 488 isolates, 98.12 % exhibited high biofilm formation. Biofertilizer isolates exhibited a similar biofilm formation capability as effluent isolates in summer, but greater propensity in winter. Resistance to biocides and antimicrobials varied, with tetracycline resistance reaching 19 %. Of the isolates, 25 were multidrug-resistant (MDR), with 64 % resistant to three drugs. Positive correlations were observed between MDR and increased biofilm formation capacity in both samples, while there was negative correlation between MDR and increased biocide resistance. A higher number of MDR bacteria were found in biofertilizer compared to the effluent, revealing the persistence of E. coli resistance, posing challenges to food safety and public health. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • Red Sour Soup (RSS) post-fermentation increased flavor substances by over 25 % total amount. • L. acetotolerans induced over 50 % lactic acid increase and formed lactic acid-dominate sour taste. • Alcohols and short-chain acids increased in early- and middle-stage and then decreased. • Butyric acid was the maximum odor contributor, followed by esters. • Acid-resistant fungi induced rapid increase of esters in late-stage with low pH values. Flavor and chemical changes with microbial succession during Red-Sour-Soup (RSS) post-fermentation were urgent to be revealed for quality control. RSS post-fermentation could be divided into three stages according to acidity, nutrients exhausting and total colony counts, without coliform bacteria growth nor nitrite peak was observed. Lactobacillus acetotolerans induced over 50 % increase of lactic acid, finally conducing to the lactic acid-dominated sour taste of RSS. The volatile compounds totally increased by 25.70 % in chili sauce and 32.58 % in tomato sauce (p < 0.05). In early-/middle-stage (pH > 3.5), alcohols and short-chain fatty acids increased, and butyric acid with unpleasant odor became the maximum flavor contributor. Nevertheless, in late-stage (pH < 3.5), with the reduction of alcohols and fatty acids, esters, 2-nonanone and terpenoids with pleasant flavors increased by Clavispora lusitaniae , Pichia , Cladosporium delicatulum and Rozellomycota sp.. In conclusion, the post-fermentation, especially L. acetotolerans metabolism and aciduric fungal esterification were essential for RSS characteristic flavor formation. [ABSTRACT FROM AUTHOR]

Sorghum grains (Sorghum bicolor) are used as food components for man as well as feed for animals. However, there have been reported cases of microbial contamination on sorghum grains. The present study investigated the comparative effects of gamma rays, low energy electron beam (LEEB) and high energy electron beam (HEEB) on the microbial quality and mycotoxin levels of sorghum grains. Sorghum grains were purchased from a local market in Accra, Ghana, and packaged in zip-lock bags. Samples were exposed to irradiation doses of 2, 4, 6, 8, and 10 kGy, and the un-irradiated sorghum grains served as control. For LEEB, the ILU-6 accelerator (250 keV) was used, and for HEEB ELEKTRONIKA 10-10 accelerator (9 MeV) was used. Gamma Chamber 5000 Co-60 source was used for gamma irradiation. Total viable counts, total coliforms, Bacillus cereus , Staphylococcus aureus , Salmonella spp, yeasts, and molds counts were determined using standard methods. Aflatoxins B 1 , B 2 , G 1, and G 2 were also evaluated. The presumptive yeast and molds were further analyzed using MALDI-TOF. All three sources of irradiation significantly reduced the microbial populations of the sorghum grains, and subsequently eliminated the microorganisms at high doses. However, at 10 kGy, total viable counts as well as yeasts and molds were still detected for LEEB. Aspergillus flavus was identified as an organism associated with the sorghum grains. The aflatoxin levels were below the detection limits. Gamma rays and HEEB were more effective than LEEB. • Gamma rays, LEEB and HEEB reduced the microbial loads on the sorghum grains. • High irradiation doses from Gamma rays and HEEB eliminated the microorganisms. • Aspergillus flavus was identified as an organism associated with the sorghum grains. • The aflatoxin levels were below the detection limits. • Gamma rays and HEEB were more effective in decontaminating sorghum grains than LEEB. [ABSTRACT FROM AUTHOR]

This study sought to develop models for predicting near-term (1–3 day) fecal contamination events in coastal shellfish growing waters. Using Random Forest regression, we (1) developed fecal coliform (FC) concentration models for shellfish growing areas using watershed characteristics and antecedent hydrologic and meteorologic observations as predictors, (2) tested the change in model performance associated when forecasted, as opposed to measured, rainfall variables were used as predictors, and (3) evaluated model predictor importance in relation to shellfish sanitation management criteria. Models were trained to 10 years of coastal FC measurements (n = 1285) for 5 major shellfish management areas along the Florida (USA) coast. Model performance varied between the 5 management areas with R2 ranging from 0.36 to 0.72. Antecedent precipitation variables were among the most important predictors in the day-of forecast models in all management areas. When forecasted rainfall was included in the models, wind components became increasingly important. • 1–3 day fecal coliform forecast models were trained with regulatory shellfish data. • 5 variations of Random Forest models for 5 management areas were evaluated. • Predictive performance ranged from R2 of 0.36 to 0.72. • Using forecasted rainfall as a predictor did not improve model performance. • Variable importance differed between models, implying varied prediction mechanisms. [ABSTRACT FROM AUTHOR]

The detection all pathogenic enteric viruses in water is expensive, time-consuming, and limited by numerous technical difficulties. Consequently, using reliable indicators such as F-specific RNA phages (FRNAPH) can be well adapted to assess the risk of viral contamination of fecal origin in surface waters. However, the variability of results inherent to the water matrix makes it difficult to use them routinely and to interpret viral risk. Spatial and temporal variability of surface waters can lead to underestimate this risk, in particular in the case of low loading. The use of bivalve mollusks as accumulating systems appears as a promising alternative, as recently highlighted with the freshwater mussel Dreissena polymorpha , but its capacity to accumulate and depurate FRNAPH needs to be better understood and described. The purpose of this study is to characterise the kinetics of accumulation and elimination of infectious FRNAPH by D. polymorpha in laboratory conditions, formalised by a toxico-kinetic (TK) mechanistic model. Accumulation and depuration experiments were performed at a laboratory scale to determine the relationship between the concentration of infectious FRNAPH in water and the concentration accumulated by D. polymorpha. The mussels accumulated infectious FRNAPH (3–5.4 × 104 PFU/g) in a fast and concentration-dependent way in only 48 h, as already recently demonstrated. The second exposure demonstrated that the kinetics of infectious FRNAPH depuration by D. polymorpha was independent to the exposure dose, with a T 90 (time required to depurate 90 % of the accumulated concentration) of approximately 6 days. These results highlight the capacities of D. polymorpha to detect and reflect the viral pollution in an integrative way and over time, which is not possible with point water sampling. Different TK models were fitted based on the concentrations measured in the digestive tissues (DT) of D. polymorpha. The model has been developed to formalise the kinetics of phage accumulation in mussels tissues through the simultaneous estimation of accumulation and depuration rates. This model showed that accumulation depended on the exposure concentration, while depuration did not. Standardized D. polymorpha could be easily transplanted to the environment to predict viral concentrations using the TK model defined in the present study to predict the level of contamination of bodies of water on the basis of the level of phages accumulated by the organisms. It will be also provide a better understanding of the dynamics of the virus in continental waters at different time and spatial scales, and thereby contribute to the protection of freshwater resources. [Display omitted] • D. polymorpha accumulates infectious FRNAPH rapidly, in a dose-dependent way. • D. polymorpha depurates infectious FRNAPH in a dose-independent way. • A toxicokinetic model was defined to estimate the T 90 and bioconcentration factors. [ABSTRACT FROM AUTHOR]

Vegetables in Cambodia are commonly sold in informal markets lacking food safety standards and controls. Current data on microbial contamination of vegetables in Cambodian informal markets are limited. The purpose of this study was to investigate Salmonella enterica and indicator organisms (Escherichia coli and coliforms) on the surface of fresh vegetables sold in informal markets in Cambodia. Samples of loose-leaf lettuce, tomatoes, and cucumbers were collected from 104 vendors at four informal markets in Battambang and Siem Reap provinces during the rainy and dry seasons. Detection methods for S. enterica were adapted from the U.S. Food and Drug Administration's Bacteriological Analytical Manual. Coliform and E. coli populations were quantified by plating onto E. coli/coliform count plates. S. enterica was most prevalent on lettuce during the dry season (56.5%, 95% confidence interval [CI] [41.0, 70.8]) than during the rainy season (15.4%, 95% CI [7.5, 29.1]), whereas no significant seasonal differences were apparent for tomatoes and cucumbers. Regardless of season, levels of S. enterica were highest on lettuce (5.7 log CFU/g, 95% CI [5.5, 5.9]), relative to cucumbers (4.2 log CFU/g, 95% CI [3.8, 4.6]) and tomatoes (4.3 log CFU/g, 95% CI [4.1, 4.6]). For E. coli, prevalence was higher during the rainy season (34.0%, 95% CI [25.4, 43.8]) than during the dry season (9.1%, 95% CI [4.9, 16.5]), with the highest prevalence estimated on lettuce. Coliform levels on lettuce and tomatoes were greater during the rainy season (6.3 and 5.3 log CFU/g, 95% CI [5.7, 6.8] and [4.7, 5.8], respectively) than during the dry season (5.2 and 3.9 log CFU/g, 95% CI [4.7, 5.7] and [3.4, 4.4], respectively). These results indicate seasonal patterns for microbial prevalence in lettuce and an overall high level of bacterial contamination on raw vegetables sold in Cambodian informal markets. [ABSTRACT FROM AUTHOR]

In contrast to the study in other part of the world, information about characteristics of plasmids carrying antimicrobial resistance genes (ARGs) in Enterobacteriaceae derived from environmental water in tropical Asian countries including Thailand is limited. This study, therefore, aimed to gain insight into genetic information of antimicrobial resistance in environmental water in Thailand. Coliform bacteria were isolated from environmental water collected at 20 locations in Thailand and identified. Then, susceptibility profiles to ampicillin, cefazoline, cefotaxime, kanamycin, ciprofloxacin, sulfamethoxazole, tetracycline, and nalidixic acid were assessed. In addition, antimicrobial resistant genes integrons, and replicon types were analyzed. And furthermore, plasmids carrying bla TEM and tetM were identified by S1-PFGE analysis and confirmed transmissibility by transconjugation experiments. In 130 coliform bacteria isolated, 89 were resistant to cefazoline while 41 isolates were susceptible. Cefazoline-resistant coliform bacteria were found to be significantly resistant to cefotaxime and tetracycline as compared to susceptible isolates. Hence, bla TEM and tetM correlating with β-lactam antibiotics and tetracycline, respectively, were analyzed found to co-localize on the IncFrepB plasmids in isolates from pig farms' wastewater by S1-PFGE analysis. And furthermore, transmissibility of the plasmids was confirmed. Results obtained in this study suggested that ARGs in coliform bacteria may have been spreading on the farm via IncFrepB plasmids. Hence, appropriate use of antimicrobials and good hygiene management on the farm are required to prevent the emergence and spread of resistant bacteria. [ABSTRACT FROM AUTHOR]

The primary objective of this study was to evaluate the protective efficacy of a novel recombinant subunit vaccine containing the protein YidR (rYidR) against clinical mastitis (CM) caused by Klebsiella spp. and Escherichia coli. Given that E. coli infection is known to cause metritis, we also evaluated the effect of rYidR vaccination on the incidence of metritis and conception at the first artificial insemination. Retained placenta and abortion incidence, milk production and composition, and serological responses to specific antigens were also evaluated. In total, 3,107 cows were blocked by parity and randomly allocated into 1 of 3 treatment groups: experimental recombinant subunit vaccine containing the YidR protein (rYidR); commercial vaccine composed of Klebsiella pneumoniae siderophore receptors and porin protein (Kleb-SRP; KlebVax, Epitopix, Willmar, MN); and sterile water adjuvanted with aluminum hydroxide (20%; placebo). Vaccinations were performed at the dry-off for cows, and at 223 ± 3 d of pregnancy for pre-fresh heifers. A second administration was given at 21 ± 3 d after the first injection. Vaccination with rYidR significantly reduced the incidence of CM caused by Klebsiella spp. (3.2%) when compared with the placebo (5.1%) group. No difference was observed on risk of Klebsiella CM between Kleb-SRP (5.9%) and placebo groups. Cows in the rYidR group that experienced E. coli CM had a lower risk of death or culling (12.5%) compared with the Kleb-SRP (27.6%) and placebo groups (27.8%). Furthermore, among cows that developed E. coli CM, rYidR-immunized cows produced more milk than did cows in the placebo and Kleb-SRP groups. Regardless of CM occurrence, rYidR-immunized cows tended to have higher milk production up to the eighth month of lactation than cows in the other groups. No significant effect of treatment was observed on the overall incidence of abortion and metritis; however, the risk of retained placenta tended to be lower for the rYidR group (4.7%) compared with the placebo group (6.7%). In addition, primiparous cows in the rYidR group had the highest conception risk at the first artificial insemination (48.3%) compared with the placebo (39.5%) group, and no significant difference was observed when the Kleb-SRP (40.1%) group was compared with the placebo group. Generally, higher antibody serum titers (IgM and IgG) were observed for the immunized groups compared with the placebo. In conclusion, the rYidR vaccine reduced the risk of CM caused by Klebsiella spp. and the mortality or culling of cows with E. coli infections. Other benefits of the novel vaccine include maintenance of milk production after CM caused by E. coli , and higher conception risk at the first service in primiparous cows compared with cows in the placebo and Kleb-SRP groups. [ABSTRACT FROM AUTHOR]

The bedding material used in barns for dairy cows has a significant effect on animal welfare and performance. Bedding influences the duration in which animals remain lying down and, consequently, the processes of rumination and milk production. It is crucial to have a complete understanding of the properties of bedding materials and the effects of alternative bedding materials on dairy cattle. This paper aims to evaluate the physical, chemical, and biological properties of various alternative and conventional bedding materials for dairy cattle for use in compost bedded pack or freestall barn systems. We analyzed 50 samples of 17 bedding materials produced in 3 European countries. We analyzed physical properties including the water holding capacity, porosity, moisture content, bulk density, dry bulk density, and particle size. Chemical analyses were performed to determine the total N, total organic C, and C:N ratio. In the biological analyses, the Escherichia coli count, total bacteria count, coliform count, and Klebsiella spp. count were assessed. The results demonstrated how the physical properties of the bedding materials may influence the chemical and biological properties. All of the materials presented adequate chemical properties to be used as bedding material. The physical properties of the bedding materials differed widely among the materials except for the dry bulk density, which presented no difference. Moreover, the contamination of each studied microorganism was observed for each bedding material to determine which material had the lowest level of contamination. Posidonia oceanica, Miscanthus grass, and spelt husks could be considered as a potential alternative material for use as bedding material for dairy cows in both systems (i.e., composted bedded pack and freestall). This experiment illustrated the importance of performing thorough physical, chemical, and biological analyses before implementing a material as bedding for dairy cattle. [ABSTRACT FROM AUTHOR]

Biopolymer films based on furcellaran-whey protein isolate (FUR/WPI) and furcellaran-whey protein isolate incorporated with yerba mate extract (FUR/WPI + YM) and with white tea extract (FUR/WPI + WT) were successfully developed and investigated as active packaging materials for fresh soft rennet-curd cheese. YM improved water vapour permeability, water content, solubility, modulus elasticity, puncture strength and thermal stability of film. Water content and water activity decreased (P ≤.05) during storage in cheese packed in each kind of the biopolymer films. These parameters did not change (P >.05) in control wrapped in linear low-density polyethylene (LLDPE). Likewise, pH decreased with the exception of the application of LLDPE and FUR/WPI + YM. In those cheese samples pH did not differ (P >.05) during storage. Total bacteria count decreased (P ≤.05) in the cheese samples wrapped in edible films during storage. However, their levels were not significantly lower than control samples when compared within the storage week. The yeast and mould counts did not differ (P >.05) during storage for the cheese packed in FUR/WPI + WT, whereas it increased in other cheese samples. The coliform bacteria count decreased (P ≤.05) during storage in all examined cheese samples. Overall organoleptic quality was more often rated as desirable and very desirable in cheese packed in edible films than in LLDPE. Unlabelled Image • FUR/WPI based films with green tea or yerba mate were successfully developed. • Yerba mate improved physical and mechanical properties of films. • Active films were used for fresh soft rennet-curd cheese during storage. • Active packaging prolonged the shelf life of fresh soft rennet-curd cheese. [ABSTRACT FROM AUTHOR]

Using high-strength wastes, such as grease trap waste mixture (GTWM) from multiple commercial facilities, as a co-substrate in anaerobic digestion can contribute to a significant increase in methane production. However, challenges such as long chain fatty acids (LCFAs) accumulation, sludge flotation, washout and scum formation can lead to digester failure. In this study, the optimal operating condition to achieve the highest methane production from an anaerobic, semi-continuous flow, mesophilic co-digester at a solids retention time of 20 days was determined. The ratio of GTWM/sludge was increased based on volatile solids (VS) concentration from 10% to 50% in 10% increments. A 40% GTWM/sludge ratio was determined to be optimum in which up to 22%, 200% and 68% improvements in VS removal, daily biogas production and specific methane production, respectively, were observed with respect to control utilizing sludge only. Beyond a 40% GTWM/sludge, the anaerobic co-digester experienced failure and addition of biochar to mitigate LCFA inhibition to failing co-digester could not recover the process. Digester LCFA concentrations were also measured during stable and unstable digester operations. • Grease trap waste (GTW) increased daily biogas yield from sludge digester by 200%. • Beyond 40% GTW/sludge ratio (volatile solids basis), digester failure was observed. • GTW had no impact on digestate fecal coliform, dewaterability and heavy metals. • In batch assays, biochar removed inhibitory long chain fatty acids from digestate. [ABSTRACT FROM AUTHOR]

Postpasteurization contamination (PPC) of fluid milk remains a challenge for some dairy processors. Pseudomonas is the most common contaminant of fluid milk after pasteurization, and therefore methods to detect PPC should be inclusive of Pseudomonas and other gram-negative contaminants (e.g., coliform bacteria). Our objective was to compare the ability of 3M (St. Paul, MN) coliform and Enterobacteriaceae (EB) Petrifilm to detect total gram-negative bacteria with that of the standard method, crystal violet tetrazolium agar. To that end, we evaluated coliform Petrifilm, EB Petrifilm, and crystal violet tetrazolium agar to detect gram-negative bacteria in naturally contaminated samples of fluid milk. A total of 92 observations derived from shelf-life testing of 33 milk samples from 5 different processing facilities were evaluated for (1) presence of coliforms on coliform Petrifilm at both 24 and 48 h of incubation; (2) presence of any growth, regardless of gas production, on coliform Petrifilm at both 24 and 48 h of incubation; (3) presence of EB on EB Petrifilm at both 24 and 48 h of incubation; (4) presence of any growth, regardless of gas or acid production, on EB Petrifilm at both 24 and 48 h of incubation; and (5) presence of gram-negative bacteria on crystal violet tetrazolium agar after 48 h of incubation. Sensitivity and specificity analysis of results indicated that compared with the standard method (i.e., crystal violet tetrazolium agar), the method that performed the best, based on balanced accuracy (i.e., the average of sensitivity and specificity), was coliform Petrifilm evaluated for the presence of any growth after 48 h of incubation (sensitivity = 0.787; specificity = 0.839). This method can be easily adopted by the dairy industry as many processing facilities already test for coliforms using coliform Petrifilm. Improving the ability of processors to detect PPC will improve the quality of the fluid milk supply. [ABSTRACT FROM AUTHOR]

A study was undertaken to examine hygienic control of the slaughter and dressing process for beef cattle at Australian export processing establishments. Samples were collected from two points during the process: immediately after hide removal and at the completion of dressing before the commencement of chilling. Hindquarter and forequarter samples were collected from 24 establishments, half of which (n=12) used some form of microbial intervention (in addition to trimming). The overall contamination level on carcass sides was low and was reduced between hide removal and entering the chiller. The concentration and prevalence of indicator bacteria were higher on samples from hindquarters than on samples from forequarters. Application of an intervention, such as hot water, in addition to trimming resulted in a greater reduction in the concentration and prevalence of indicator bacteria than trimming alone, although the level of Escherichia coli and coliform bacteria on all samples was too low to allow meaningful comparisons to be made. Salmonellae were isolated from 2.09 and 0.56% of samples after hide removal and before chilling, respectively. Application of an intervention in addition to trimming did not result in a significant reduction (P = 0.4) of Salmonella prevalence on prechill carcasses. Low levels of bacteria were found on carcasses after hide removal. This, combined with small reductions as a result of trimming and sometimes other interventions, resulted in carcasses with very low levels of bacterial contamination. If performance metrics were to be applied to the slaughter and dressing process, a measure of the expected contamination at the end of the process would provide a more unequivocal measure of the process than either contamination on the carcass after hide removal or any reduction achieved as a result of the dressing process. [ABSTRACT FROM AUTHOR]

To correctly assess and properly manage the public health risks associated with exposure to contaminated water, it is necessary to identify the source of fecal pollution in a watershed. In this study, we evaluated the efficacy of our two previously developed real time-quantitative PCR (qPCR) assays for the detection of swine-associated Bacteroidales genetic markers (gene 1–38, gene 3–53) in the Yangtze Delta watershed of southeastern China. The results indicated that the gene 1–38 and 3-53 markers exhibited high accuracy (92.5%, 91.7% conditional probability, respectively) in detecting Bacteroidales spp. in water samples. According to binary logistic regression (BLR), these two swine-associated markers were well correlated (P < 0.05) with fecal indicators (Escherichia coli and Enterococci spp.) and zoonotic pathogens (E. coli O157: H7, Salmonella spp. and Campylobacter spp.) in water samples. In contrast, concentrations of conventional fecal indicator bacteria (FIB) were not correlated with zoonotic pathogens, suggesting that they are noneffective at detecting fecal pollution events. Collectively, the results obtained in this study demonstrated that a swine-targeted qPCR assay based on two Bacteroidales genes markers (gene 1–38, gene 3–53) could be a useful tool in determining the swine-associated impacts of fecal contamination in a watershed. Image 1 [ABSTRACT FROM AUTHOR]

The effects of 3 ethanol levels (30, 50, and 70%) with and without thiamine dilaurylsulfate (TDS; 1,000 ppm) were evaluated for the reduction of natural mesophilic aerobic bacteria (MAB), coliforms, and inoculated Salmonella Typhimurium (S. Typhimurium) in chicken skin. The chicken skin was inoculated with a 7 log cfu/mL suspension of S. Typhimurium. Loosely, intermediately, and tightly attached cells were recovered from chicken skin through shaking at 200 rpm for 5 min, stomaching for 1 min, and blending for 1 min, respectively. Increasing the ethanol concentration reduced the number of MAB, coliforms, and S. Typhimurium on the chicken skin, whereas TDS treatment without ethanol was not effective. Intermediately and tightly attached microorganisms (total MAB, coliforms, and S. Typhimurium) were more resistant to chemical disinfectants than loosely attached microorganisms. The combination of 70% ethanol with TDS was most effective than the combination of TDS with lower concentrations of ethanol in reducing populations of loosely, intermediately, and tightly attached MAB (by 1.88 log cfu/g, 1.21 log cfu/g, and 0.84 log cfu/g, respectively), coliforms (by 1.14 log cfu/g, 1.04 log cfu/g, and 0.67 log cfu/g, respectively), and S. Typhimurium (by 1.62 log cfu/g, 1.72 log cfu/g, and 1.27 log cfu/g, respectively). However, the chicken skin treated with higher concentrations of ethanol was tougher (P< 0.05) and more yellow and less red (P < 0.05) than that treated with lower concentrations of ethanol or with water (control). On the other hand, a combination of 30% ethanol and TDS yielded the best results, showing the reduction greater than 0.5 log cfu/g in S. Typhimurium, with no negative effect on chicken skin color or texture. Thus, a combination of 30% ethanol and TDS appears to be the optimal treatment for reducing microbial contamination of skin-on chicken products to enhance poultry safety without decreasing food quality, and this treatment could be applied in the poultry industry. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the effect of supplementing enzymatically hydrolyzed yeast (EHY; Celmanax Arm and Hammer Animal Nutrition, Princeton, NJ) on transition dairy cattle. Forty multiparous Holstein cows were blocked by predicted transmitting ability and randomly assigned to 1 of 2 treatments (EHY, n = 20; or control, CON, n = 20) from 21 d before expected calving to 60 d postpartum. The EHY cows received 56 and 28 g/d in close-up and lactating diets, respectively. Dry matter intake, health events, milk production parameters, feed efficiency, colostrum quality, reproductive parameters, body weight, and body condition score were monitored. Fecal samples collected on −21, −14, −7, 0, 1, 3, 5, 7, and 14 d relative to calving were analyzed for total coliforms, Clostridium perfringens , Salmonella , and Escherichia coli O157:H7. Blood samples were collected at 7, 14, and 21 d postpartum for analysis of β-hydroxybutyrate. Sterile quarter milk samples collected at dry-off, calving, and wk 1, 2, and 3 of lactation were analyzed for milk pathogens and somatic cell count. Pre- or postpartum dry matter intake, body weight, body condition score, milk yield, and milk protein and fat yields did not differ among treatments. Milk fat and protein concentrations were greater in EHY cows than CON cows. β-Hydroxybutyrate and health events were not different among treatments. The presence of fecal C. perfringens did not differ prepartum, but was lower in EHY cows postpartum. Milk pathogens and total intramammary infections did not differ between treatments at dry-off, calving, wk 1, or wk 2, but more EHY cows were infected with Staphylococcus sp. during wk 3 than CON cows. The EHY cows showed heat earlier than CON cows, but no other reproductive parameters were affected. The EHY supplementation during the transition period did not affect dry matter intake, milk yield, health events, or reproductive parameters but did increase milk protein and fat concentrations. [ABSTRACT FROM AUTHOR]

Although water quality from freshwater recreational aquatic environments (RAEs) has been long analyzed worldwide, little information is available about their sediments. The aim of this work was to study the physicochemical and bacteriological quality of water and sediment under different seasonal events. For that, Wierna River (WR) and General Belgrano reservoir (GB) were used as freshwater RAEs models. A total of 33 water and 33 sediment samples (15 from WR and 18 from GB from each phase) were collected and analyzed. Physicochemical variables in water (pH, turbidity, dissolved oxygen, temperature, conductivity, alkalinity, hardness) and sediments (organic matter, humidity, ash, and conductivity) were measured. For the bacteriological characterization, total aerobic mesophiles, total and thermotolerant coliforms, E. coli, enteroccocci, Salmonella spp., and Pseudomonas aeruginosa were evaluated using culture-based methods. Universal and human Bacteroides were also quantified by real-time PCR. Univariate (Kruskall-Wallis), bivariate (Spearman correlation), and multivariate (cluster analysis, principal component analysis) statistical techniques were applied for data analysis. All bacterial indicators were almost two-logs higher in sediments than in water, for both RAEs. Also, due to rainfall events and recreational activities, sediments were resuspended in surface water exceeding in most cases the limit values established by international regulation for bacteria. Significant correlation was observed between culturable bacteria and turbidity (p < 0.05) supporting this. We found that while physicochemical variables clustered samples by geographical location in water and sediments, microbiological aggrupation in water was mostly driven by seasonal events. No aggrupation was observed when using microbiological variables in sediments. Thus, geographical location, type of water and sediments, and seasonal events influenced on RAEs quality. Including sediment analysis during RAEs monitoring campaigns is essential as it will allow knowing the real health risk to which bathers are exposed and proposing solutions to mitigate it. [ABSTRACT FROM AUTHOR]

Because cloth udder towels (CUT) may function as a fomite for mastitis-causing pathogens, most udder health laboratories offer towel culture services as a tool to monitor towel hygiene. However, no studies have investigated if an association exists between bacteria levels in CUT and udder health outcomes. The objectives of this cross-sectional study were to (1) describe associations between herd-level measures of towel bacteria count (ToBC) and quarter-level intramammary infection (IMI) status in late-lactation cows, (2) establish pathogen-specific target levels of bacteria in CUT to aid the interpretation of towel culture reports, and (3) identify laundering-related risk factors for high ToBC. The study was conducted in 67 herds from 10 dairy states in the United States that used CUT. These 67 herds were originally recruited as part of a larger (80 herd) cross-sectional study of bedding management. Each herd was visited once during December 2017 to April 2018 and quarter-milk samples (n = 4,656) were collected from late-gestation (>180 d pregnant) cows (n = 1,313). Two recently laundered CUT were collected and a questionnaire was used to collect information about pre-milking teat preparation and CUT management practices. Quarter-level IMI status was determined using standard bacteriologic methods. In addition, colony-forming units of all bacteria (total bacteria), Staphylococcus spp., Streptococcus spp. or Streptococcus -like organisms (SSLO), coliforms, noncoliform gram-negatives, and Bacillus spp. were determined for each pair of CUT (log 10 cfu/cm2). The association between ToBC and IMI was determined using multivariable logistic regression with mixed effects. After dichotomizing ToBC into high and low categories, associations between towel management practices and ToBC category were determined using unconditional logistic regression. The quarter-level prevalence of IMI was 19.6%, which was predominantly caused by non- aureus Staphylococcus spp. (NAS; 10.2%) and SSLO (5.1%). The predominant bacteria in CUT were Bacillus spp. (median = 3.13 log 10 cfu/cm2). Total bacteria count was not associated with odds of IMI (odds ratio = 1.06), likely due to the predominance of Bacillus spp. in CUT and low number of IMI caused by Bacillus spp. In contrast, counts of Staphylococcus spp. and SSLO were positively associated with odds of IMI caused by NAS (odds ratio = 1.33) and SSLO (odds ratio = 1.45), respectively. Of 12 CUT management practices evaluated, only the failure to use a dryer was identified as a clear predictor of risk for a high ToBC (risk ratio of high coliform count = 8.17). Our study findings suggest that CUT may act as a fomite for NAS and SSLO. We recommend that herds aim to keep counts of Staphylococcus spp. and SSLO in CUT below 32 cfu/cm2 (or 5 cfu/in2), and that laundered towels be completely dried in a hot air dryer. [ABSTRACT FROM AUTHOR]

The aim of this study was to quantify, identify, evaluate antimicrobial resistance, and characterize the virulence factors of enteropathogenic (EPEC), Shiga-toxigenic (STEC), and enterohemorrhagic (EHEC) Escherichia coli in raw milk (RM) and legal (LMFC) and illegal (IMFC) Minas Frescal cheeses in southern and northeast Brazil. Illegal cheeses are those made without official inspection service or sanitary surveillance. We evaluated samples of RM produced in Paraná (southern) and Maranhão (northeast) States, LMFC produced using pasteurized milk in inspected industries, and IMFC potentially produced with raw milk. Mean total coliform counts were 8.4 × 104 cfu/mL for RM, 1.4 × 107 cfu/mL for LMFC, and 2.9 × 107 cfu/mL for IMFC. Mean E. coli counts were 2.4 × 103 cfu/mL for RM, 1.9 × 102 cfu/mL for LMFC, and 1.1 × 105 cfu/mL for IMFC. Among the 205 E. coli isolates from RM, 9.75% were identified as EPEC, mainly (90%) in samples from Paraná. Of the total isolates from the cheese samples, 97.4% (n = 111) came from IMFC, of which 1.8 and 2.7% were identified as EPEC and STEC, respectively; no EHEC was detected. The phylogenetic group A (60%) and typical EPEC (68%) predominated, which confirms the possible human origin of pathogenic isolates in RM and IMFC. Of these, 50% were resistant to at least one antibiotic, and streptomycin was the antimicrobial with the highest number (8) of EPEC and STEC resistant isolates. This study reports the first isolation of serogroup O28ac in Brazilian milk. We found no predominance of a specific serogroup of EPEC or STEC in milk or cheese or clonal isolates in the same sample, indicating different origins of the contamination in these products, presumably mostly related to poor hygienic handling. [ABSTRACT FROM AUTHOR]

Poultry meats can become contaminated with pathogenic bacteria through digesta leakage during processing. Reducing the bacteria load in digesta of market-aged broilers prior to processing reduces the incidence of fecal contamination at the processing plant. A lysozyme product was incorporated in a maltodextrin-based feed offered during the pre-shipping feed withdrawal period to reduce bacteria in ileal contents of market-aged broilers. Twenty 36-day-old broilers were randomly allocated to each of 16 pens. For a 9 h period each pen was randomly assigned to one of the following treatments: no feed, maltodextrin-based feed with a lysozyme product (Inovapure) added at 0, 10, or 20 g per kg of feed. Feed consumption was determined and a minimum of 3 birds were randomly selected from each pen and euthanized. The ileal contents were removed and weighed. Samples were analyzed for Clostridium perfringens , aerobic bacteria, Enterobacteriaceae, E. coli , and coliform numbers using standard culturing techniques and next generation sequencing was performed to determine population shifts. Bacteria counts were transformed to log10 colony forming units (cfu) and analyzed as a completely randomized design. The data from next generation sequencing was analyzed as a 3 × 5 factorial design using Proc Mixed of SAS. Lysozyme did not affect feed consumption nor were the weight of ileal contents different for birds fed maltodextrin-based feeds compared to birds on traditional feed withdrawal. E. coli /coliforms and Enterobacteriaceae plates had no signs of bacterial growth. The number of Clostridium perfringens and aerobic bacteria in the ileal contents of market-aged broilers was not different between treatments using the traditional culturing techniques. Next generation sequencing was a useful alternative to traditional culture techniques as results revealed that bacilli were reduced and clostridia increased for the 20 g lysozyme treatment. Addition of lysozyme to a maltodextrin based feed did not change overall numbers of bacteria but was effective in altering the participants in the bacteria community in ileal contents of market-aged broilers. [ABSTRACT FROM AUTHOR]