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Quorum sensing is a well-known mechanism used by many bacteria to control important virulence factors through the production and subsequent response to N-acylhomoserine lactones (AHLs). Quorum sensing inhibition (QSI), targeting AHL-dependent signalling, has been reported as a strategy for the control of bacterial pathogenicity. Thus, this study aimed at investigating the capability of Pseudomonas aeruginosa as an indicator to rapidly screen for potential QSI caused by plant extracts based on pigment inhibition. Four ethanolic plant extracts including: dried flower buds of clove (Syzygium aromaticum L), bark of cinnamon (Cinnamomum cassia L), leaves of moringa (Moringa oleifera Lam), and Al-Gutub (Tribulus terrestris L) dried fruits were investigated for their QSI ability in comparison with furanone (the known QS inhibitor). Agar well diffusion assay was used, in which the indicator isolate, P. aeruginosa, was inoculated onto Pseudomonas special agar medium containing 8 mm wells to load different concentrations of the plant extracts along with furanone or phosphate buffered saline (negative control). The results showed that furanone was successful in inhibiting the pyocyanin pigment of P. aeruginosa without interfering with the bacterial growth, this verified the ability of this bacterium as a potent QS indicator organism. Importantly, clove extract at different concentrations caused complete inhibition of the pyocyanin pigment with little impact on the bacterial growth. On the use of cinnamon, only the high concentrations showed clear dye inhibition of the indicator organism. Moringa also caused certain degree of dye inhibition but only at high concentrations. Conversely, Al-Gutub neither affected on the pyocyanin production nor on the bacterial viability. In conclusion, P. aeruginosa isolate, pyocyanin producer, was successful in the screening of QS inhibitors. This simple study recommends the use of such isolate without relying on the import of certain strains of Chromobacterium violaceum, Pseudomonas aureofaciens, or Agrobacterium tumefaciens‎‎‎‎‎.

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Guanabara Bay has been known to be polluted with trash and sewage from the surrounding areas, but health risks from recreational contact with water in the basin have not been well characterized. In this paper, fecal indicator bacteria (FIB) monitoring data are used to predict risks in three different exposure scenarios: (1) bathing in freshwater rivers that discharge into Guanabara Bay, (2) wading in these freshwater rivers, and (3) sailing in Guanabara Bay. Concentrations of indicator bacteria in river samples were measured directly, and concentrations of indicator bacteria in bay samples were sourced from publicly available government data sets. Ratios between pathogens and fecal indicator concentrations were used to estimate risks for five selected pathogens based on the indicator concentrations. The median risk of disease estimated from E. coli indicator concentrations was 1.0, 9.9 × 10−1 and 8.2 × 10−4 for the swimming, wading, and sailing exposure pathways, respectively. Risks estimates based on concentrations of the enterococci indicator bacteria in the sailing exposure scenario were comparable, at 3.4 × 10−4. The sum of total risk estimated from the five selected pathogens was 5.9 × 10−1, 3.6 × 10−1, and 1.0 × 10−3 for the swimming, wading, and sailing exposure pathways, respectively. Estimated risks of swimming and wading in the rivers far exceeded risks associated with U.S. recreational contact standards, while estimated risks for sailing in the bay were well below these risk guidelines. The 95th percentile of the sailing risk was estimated to exceed the U.S. recreational contact risk level. This paper exemplifies an approach to conducting quantitative microbial risk assessments when only fecal indicator bacteria data are available. Context-specific data on the relevant exposure routes, exposure frequency, and site-specific indicator: pathogen ratios were lacking, which ultimately led to uncertainty in the model. This study is intended to provide a framework for estimating GI risk based on fecal indicator concentrations while acknowledging that the substantial variation in indicator:pathogen ratios make the results of such efforts uncertain. [ABSTRACT FROM AUTHOR]

Simple Summary: Antimicrobial resistance (AMR) is a concern that impacts both human and animal health. To understand AMR, a detailed analysis of 14 different studies was carried out. This study specifically focused on resistance to tetracycline, a common antibiotic, in E. coli bacteria present in cattle. The study found that 0.31 of the E. coli from beef cattle not treated with antibiotics were resistant to tetracycline. Surprisingly, when beef cattle were given the antibiotic through feed or injection, the resistance only rose slightly to 0.53 and 0.39, respectively. This challenges the common belief that using lots of antibiotics in livestock causes higher resistance. The results varied greatly across studies, likely due to different factors like cattle genetics, environment, management, and how antibiotics are given. Other factors, such as exposure to antibiotics in the environment, natural resistance mechanisms in E. coli, and the ability of bacteria to share resistance traits, could also play a part. The study was limited by inconsistent data and a lack of standardization across the studies. Hence, the results highlight the need for tailored research on AMR, to gain a comprehensive understanding of the influencing factors and to devise effective countermeasures. Antimicrobial resistance (AMR) is an emerging global concern, with the widespread use of antimicrobials in One Health contributing significantly to this phenomenon. Among various antimicrobials, tetracyclines are extensively used in the beef cattle industry, potentially contributing to the development of resistance in bacterial populations. This meta-analysis aimed to examine the association between tetracycline use in beef cattle and the development of tetracycline resistance in Escherichia coli isolates. A comprehensive search was conducted using multiple databases to gather relevant observational studies evaluating tetracycline use and tetracycline resistance in Escherichia coli isolates from beef cattle. The rate of tetracycline resistance from each study served as the effect measure and was pooled using a random-effects model, considering possible disparities among studies. The meta-analysis of 14 prospective longitudinal studies resulted in a 0.31 prevalence of tetracycline resistance in Escherichia coli in non-intervention (no exposure), contrasting numerically elevated resistance rates in the intervention (exposed) groups of 0.53 and 0.39 in those receiving tetracyclines via feed or systemically, respectively. Despite the observed numerical differences, no statistically significant differences existed between intervention and non-intervention groups, challenging the conventional belief that antimicrobial use in livestock inherently leads to increased AMR. The findings of this study underscore the need for additional research to fully understand the complex relationship between antimicrobial use and AMR development. A considerable degree of heterogeneity across studies, potentially driven by variations in study design and diverse presentation of results, indicates the intricate and complex nature of AMR development. Further research with standardized methodologies might help elucidate the relationship between tetracycline use and resistance in Escherichia coli isolated from beef cattle. [ABSTRACT FROM AUTHOR]

Escherichia coli is a harmful pathogenic bacterial species causing serious intestinal sickness in humans. This bacterium has been linked to contaminated epidemics that have led to significant mortality and morbidity across the world. E. coli, like most other waterborne infections, is tricky to discover effectively in the water supply. Therefore, there is a demand for advanced E. coli detection methods that can sensitively and rapidly detect these pathogens. This review reveals several approaches used for the detection of E. coli bacteria using conventional methods such as multiple tube fermentation and membrane filtration techniques. The emerging approaches give quite accurate and speedy identification despite the necessity for culturing; nevertheless, they lack precision and necessitate extra lab testing. Because analytical techniques such as GC‐DMS lack specificity, the invention of a sensing device that is simple to use, compact, extremely sensitive, and specific has proven essential in identifying incredibly low concentrations of harmful E. coli in drinking water. [ABSTRACT FROM AUTHOR]

Antimicrobial resistance (AMR) is an emerging global concern, with the widespread use of antimicrobials in One Health contributing significantly to this phenomenon. Among various antimicrobials, tetracyclines are extensively used in the beef cattle industry, potentially contributing to the development of resistance in bacterial populations. This meta-analysis aimed to examine the association between tetracycline use in beef cattle and the development of tetracycline resistance in Escherichia coli isolates. A comprehensive search was conducted using multiple databases to gather relevant observational studies evaluating tetracycline use and tetracycline resistance in Escherichia coli isolates from beef cattle. The rate of tetracycline resistance from each study served as the effect measure and was pooled using a random-effects model, considering possible disparities among studies. The meta-analysis of 14 prospective longitudinal studies resulted in a 0.31 prevalence of tetracycline resistance in Escherichia coli in non-intervention (no exposure), contrasting numerically elevated resistance rates in the intervention (exposed) groups of 0.53 and 0.39 in those receiving tetracyclines via feed or systemically, respectively. Despite the observed numerical differences, no statistically significant differences existed between intervention and non-intervention groups, challenging the conventional belief that antimicrobial use in livestock inherently leads to increased AMR. The findings of this study underscore the need for additional research to fully understand the complex relationship between antimicrobial use and AMR development. A considerable degree of heterogeneity across studies, potentially driven by variations in study design and diverse presentation of results, indicates the intricate and complex nature of AMR development. Further research with standardized methodologies might help elucidate the relationship between tetracycline use and resistance in Escherichia coli isolated from beef cattle.

This study aimed to monitor microbial contamination levels in a variety of health functional foods and to establish new microbial criteria. Indicator organisms (i.e., aerobic bacteria, coliform bacteria, and Escherichia coli) were monitored in 10 health functional food categories (743 items, 3,715 samples). The mean total aerobic counts of ginseng and Korean red ginseng were −0.35 and −0.74 log CFU/g; and the mean total coliform counts were −1.4 and −1.39 log CFU/g, respectively. In addition, the mean total coliform counts of fiber and protein products were −1.34 and −1.22 log CFU/g, respectively. However, no aerobic or coliform cells were detected in any other health functional food products (vitamins, minerals, probiotics, milk thistle extract, propolis, eicosapentaenoic acid, docosahexaenoic acid, or lutein products), and no E. coli was detected in any of the categories. These results can potentially be used to update the microbial criteria of the Health Functional Food Code. [ABSTRACT FROM AUTHOR]

In pigs, antimicrobial use (AMU) practices vary at different production phases between herds and between countries. Antimicrobial resistance (AMR) development is linked to AMU but recognized as a multi-factorial issue, and thus, any information increasing knowledge of AMU and AMR relationships is valuable. We described AMU and screened the carriage of different AMR phenotypes of indicator Escherichia coli in 25 selected Finnish piglet-producing and finishing herds that formed nine birth-to-slaughter production lines. Moreover, we studied associations between AMU and AMR in both herd types and throughout the production line. Treatment records were obtained from the national Sikava register for 1year, and AMU was quantified as mg/PCU (population correction unit) and TIs (treatment incidences). For phenotypic antimicrobial susceptibility testing, ten pen-level pooled feces samples (n =250) in each herd were collected from one room representing the oldest weaned piglets or the oldest finishing pigs. Majority of the medications (96.8%) was administered parenterally, and penicillin was the predominant antimicrobial in every herd. More different antimicrobial substances were used in piglet-producing than in finishing herds (median 5 and 1, respectively, p <0.001). As mg/PCU, sows had the highest AMU and suckling piglets had the highest TIs, whereas finishing pigs were the least treated age group. The proportion of susceptible indicator E. coli isolates of all studied isolates was 59.6%. Resistance was found most commonly against tetracycline, sulfamethoxazole, trimethoprim, and ampicillin, and multi-resistant (MR) isolates (46.5% of all resistant isolates) were resistant to a maximum of four different antimicrobials. Quinolone resistance was rare, and no resistance against 3rd-generation cephalosporins, meropenem, azithromycin, colistin, gentamicin, or tigecycline was detected. The main associations between AMU and AMR were found at antimicrobial group level when use was compared with the presence of AMR phenotypes. The proportion of resistant isolates was not associated with AMU, and herd size was not associated with either AMU or AMR. We suggest that the use of narrow-spectrum beta-lactams as a primary treatment option and lack of wide application of oral group medications potentially favors a good resistance pattern in integrated pork production. [ABSTRACT FROM AUTHOR]

In pigs, antimicrobial use (AMU) practices vary at different production phases between herds and between countries. Antimicrobial resistance (AMR) development is linked to AMU but recognized as a multi-factorial issue, and thus, any information increasing knowledge of AMU and AMR relationships is valuable. We described AMU and screened the carriage of different AMR phenotypes of indicator Escherichia coli in 25 selected Finnish piglet-producing and finishing herds that formed nine birth-to-slaughter production lines. Moreover, we studied associations between AMU and AMR in both herd types and throughout the production line. Treatment records were obtained from the national Sikava register for 1year, and AMU was quantified as mg/PCU (population correction unit) and TIs (treatment incidences). For phenotypic antimicrobial susceptibility testing, ten pen-level pooled feces samples (n=250) in each herd were collected from one room representing the oldest weaned piglets or the oldest finishing pigs. Majority of the medications (96.8%) was administered parenterally, and penicillin was the predominant antimicrobial in every herd. More different antimicrobial substances were used in piglet-producing than in finishing herds (median 5 and 1, respectively, p

The present study was conducted to determine impact of application of Virkon S disinfectant in milk parlour on microbial load from possible sources of contamination and on raw milk. Therefore, this study was carried out on ten dairy cows (equal in their milk production and free from clinical and subclinical mastitis) in a private dairy farm of Holstein cows in Kafr El-Zayat, El-Gharbia Governorate. two hundred samples including 70 swabs samples from (teat cup, milk jar, teat surface, rubber tube, milk pipeline, milk tank and worker’s hand), 10 water samples, 10 individual milk samples, and 10 bulk milk tank samples, were collected regular farm application and after application of virkon S disinfectant. the obtained results revealed that worker’s hand swabs and bulk tank milk samples were the most contaminated points in milk parlour. Virkon S gave reduction percent on all investigated indicators organisms with different percent. in addition, higher reduction percent reach to 100% on coliforms counts from teat cup swabs, wash water, cow milk samples. Our study revealed that milkers’ hand, milking equipment, udder of animal, water used for cleaning and washing of equipment were the most potential sources of raw milk contamination, so these points were counted as points needs attention for production of high-quality milk. virkon S is highly effective in reducing bacterial population for quality milk production. [ABSTRACT FROM AUTHOR]

Water is an important facet of our everyday life. It plays an important role in the regulation of varying processes in the body as well as it is useful for many different recreational activities. The bottled water industry has increased over the years, and as such, this study was aimed at determining the microbial quality of packaged water sold locally. The Multitube Fermentation Test / Most Probable Number (MPN) method was employed in this study. Based on the MPN index obtained, all samples had an estimation of < 0.03g/mL of coliforms, thereby meeting the World Health Organization (WHO) standard of zero coliform per 100 ml of water, thus rendering it safe for human consumption. [ABSTRACT FROM AUTHOR]

Poultry processing systems are a complex network of equipment and automation systems that require a proactive approach to monitoring in order to protect the food supply. Process oversight requires the use of multi-hurdle intervention systems to ensure that any undesirable microorganisms are reduced or eliminated by the time the carcasses are processed into final products. In the present study, whole bird carcass rinses (WBCR) collected at the post-scalder and post-picker locations from three different poultry processing facilities (Plant A: mid-weight broiler processing, B: large-weight broiler processing, C: young broiler (Cornish) processing) were subjected to next generation sequencing (NGS) and microbial quantification using direct plating methods to assess the microbial populations present during these stages of the poultry process. The quantification of aerobic plate counts (APC) and Enterobacteriaceae (EB) demonstrated that reductions for these microbial classes were not consistent between the two sampling locations for all facilities, but did not provide a clear picture of what microorganism(s) may be affecting those shifts. With the utilization of NGS, a more complete characterization of the microbial communities present including microorganisms that would not have been identified with the employed direct plating methodologies were identified. Although the foodborne pathogens typically associated with raw poultry, Salmonella and Campylobacter, were not identified, sequence analysis performed by Quantitative Insights of Microbiology Ecology (QIIME) indicated shifts of Erwinia, Serratia, and Arcobacter, which are microorganisms closely related to Salmonella and Campylobacter. Additionally, the presence of Chryseobacterium and Pseudomonas at both sampling locations and at all three facilities provides evidence that these microorganisms could potentially be utilized to assess the performance of multi-hurdle intervention systems.

Poultry processing systems are a complex network of equipment and automation systems that require a proactive approach to monitoring in order to protect the food supply. Process oversight requires the use of multi-hurdle intervention systems to ensure that any undesirable microorganisms are reduced or eliminated by the time the carcasses are processed into final products. In the present study, whole bird carcass rinses (WBCR) collected at the post-scalder and post-picker locations from three different poultry processing facilities (Plant A: mid-weight broiler processing, B: large-weight broiler processing, C: young broiler (Cornish) processing) were subjected to next generation sequencing (NGS) and microbial quantification using direct plating methods to assess the microbial populations present during these stages of the poultry process. The quantification of aerobic plate counts (APC) and Enterobacteriaceae (EB) demonstrated that reductions for these microbial classes were not consistent between the two sampling locations for all facilities, but did not provide a clear picture of what microorganism(s) may be affecting those shifts. With the utilization of NGS, a more complete characterization of the microbial communities present including microorganisms that would not have been identified with the employed direct plating methodologies were identified. Although the foodborne pathogens typically associated with raw poultry, Salmonella and Campylobacter , were not identified, sequence analysis performed by Quantitative Insights of Microbiology Ecology (QIIME) indicated shifts of Erwinia, Serratia , and Arcobacter , which are microorganisms closely related to Salmonella and Campylobacter. Additionally, the presence of Chryseobacterium and Pseudomonas at both sampling locations and at all three facilities provides evidence that these microorganisms could potentially be utilized to assess the performance of multi-hurdle intervention systems. [ABSTRACT FROM AUTHOR]

Abstract We evaluated the relative response of generic Escherichia coli (GEC), Shiga toxin-producing E. coli (STEC) and Salmonella enterica to heat, alkaline or acid treatments. GEC included strains from carcasses (n = 24) and trim (n = 25) at a small beef plant where no decontamination interventions are used and at a large plant where multiple decontamination interventions are used (carcass n = 25 and trim n = 25). STEC strains belonging to nine serogroups, included isolates from cattle (n = 53), beef (n = 16) and humans (n = 44). S. enterica strains belonging to 29 serotypes, included isolates from humans (n = 30), poultry (n = 26), pork (n = 10) and beef (n = 33). Strains were grown in Brain Heart Infusion (BHI) broth and subjected to the following treatments: 60 °C for 2 min, 5% lactic acid (pH 2.9) for 1 h at 4 °C, or NaOH (pH 11.0) for 2 h at 4 °C. Median log reductions of the GEC populations after heat, alkaline and acid treatment ranged from 2.3 to 3.8, 0.7 to 2.2 and 0.7 to 1.2 log CFU/mL, respectively. No statistically significant difference in reductions was observed between carcass GEC or trim GEC from the large or small plant, except for a greater reduction in trim GEC from the small plant. Median reductions of the STEC populations ranged from 3.3 to 3.5, 0.0 to 0.6, and 0.3 to 0.5 log CFU/mL after heat, alkaline and acid treatment, respectively. The median reductions were not dependent upon isolation source, except between STEC cattle and human isolates after alkaline treatment, where the reduction of the former was higher by 0.6 log unit. For the Salmonella populations, median log reductions ranged from 3.5 to 4.0, 1.7 to 2.4 and 3.7 to 4.1 log CFU/mL after heat, alkaline and acid treatment, respectively. The reductions were not isolation source related. The median log reductions were in the order GEC < STEC < Salmonella after heat treatment and STEC < GEC < Salmonella after alkaline or acid treatment. Overall, the relative response of GEC, STEC and Salmonella in the model system suggests that exposure to heat or pH-based decontamination interventions in meat plants is not associated with increased resistance among E. coli strains in these environments, and total E. coli counts on beef can be indicative of treatment efficacy for the control of Salmonella by heat, lactic acid and alkaline treatment and for the control of STEC subjected to heat. Highlights • GEC, STEC and Salmonella from various sources were exposed to heat, alkaline or acid. • Exposure to these interventions is not associated with increased resistance of GEC. • Bacterial reductions were not isolation source related. • Reductions were in the order GEC < STEC < Salmonella after heat treatment. • Reductions were in the order STEC < GEC < Salmonella after acid or alkaline treatment. [ABSTRACT FROM AUTHOR]

Surveys of extended-spectrum β-lactamase-producing Enterobacteriaceae (ESBL-pE) in stream water and untreated wastewater were carried out in Okinawa Prefecture, Japan. Thirty-six samples of water were collected from 18 streams in Okinawa Prefecture, as well as ten samples of wastewater flowing into four wastewater treatment plants (WWTPs). We investigated bacterial species, Escherichia coli O antigen, ESBL phenotype, ESBL genotype, and pulsed-field gel electrophoresis (PFGE) type of isolates, and total viable count and fecal coliforms as indicator organisms. The relation between indicator organisms and ESBL-pE was also validated using the same samples. A total of 141 ESBL-pE including 107 E. coli, 15 Klebsiella pneumoniae, 2 Proteus mirabilis, and 17 other species was isolated from stream water and wastewater. Of the 141 ESBL-pE, 14.9% and 54.6% were found to be blaCTX-M-15 and blaCTX-M-14-like types, respectively, which have been found in hospital isolates in Okinawa. Two pairs of possibly related patterns according to PFGE criteria were isolated from stream water and wastewater in two districts. When ESBL-pE was significantly isolated, total viable count and fecal coliform boundaries were ≥ 6.0 × 103 CFU/ml and ≥ 4.3 × 102 most probable number/100 ml, respectively. These results suggested that ESBL-pE isolated from stream water is human derived, and that total viable count and fecal coliforms will be useful as indicators for confirming the spread of ESBL-pE to the environment by means of simple hygiene surveys. [ABSTRACT FROM AUTHOR]

We recently described the genetic antimicrobial resistance and virulence profile of a collection of 279 commensal E. coli of food-producing animal (FPA), pet, wildlife and human origin. Phenotypic antimicrobial resistance (AMR) and the role of commensal E. coli as reservoir of extra-intestinal pathogenic Escherichia coli (ExPEC) virulence-associated genes (VAGs) or as potential ExPEC pathogens were evaluated. The most common phenotypic resistance was to tetracycline (76/279, 27.24%), sulfamethoxazole/trimethoprim (73/279, 26.16%), streptomycin and sulfisoxazole (71/279, 25.45% both) among the overall collection. Poultry and rabbit were the sources mostly associated to AMR, with a significant resistance rate (p > 0.01) to quinolones, streptomycin, sulphonamides, tetracycline and, only for poultry, to ampicillin and chloramphenicol. Finally, rabbit was the source mostly associated to colistin resistance. Different pandemic (ST69/69*, ST95, ST131) and emerging (ST10/ST10*, ST23, ST58, ST117, ST405, ST648) ExPEC sequence types (STs) were identified among the collection, especially in poultry source. Both ST groups carried high number of ExPEC VAGs (pandemic ExPEC STs, mean = 8.92; emerging ExPEC STs, mean = 6.43) and showed phenotypic resistance to different antimicrobials (pandemic ExPEC STs, mean = 2.23; emerging ExPEC STs, mean = 2.43), suggesting their role as potential ExPEC pathogens. Variable phenotypic resistance and ExPEC VAG distribution was also observed in uncommon ExPEC lineages, suggesting commensal flora as a potential reservoir of virulence (mean = 3.80) and antimicrobial resistance (mean = 1.69) determinants.

Microplastics (MPs) and fouling organisms are prevalent in oceans worldwide. The study aims to investigate the pollution characteristics of MPs in fouling organisms. The study found significant inter-specific differences in the MPs abundance, while the length of MPs is consistent. The average number of MPs in N. exigua is 0.00 ± 0.00. There is a correlation between MPs abundance and weight in sessile group, while gastropods don't. Direct observation has demonstrated that the radulae of N. radula can envelop MPs. Fiber and blue are the predominant forms and colors of MPs found in fouling organisms. It is noteworthy that all film and fragment MPs observed were of a blue hue and had a size limitation of 500 μm. The characteristics of MPs between sessile organisms are more similar than those between gastropods. This study has improved our understanding of the pollution characteristics of MPs in fouling organisms, specifically gastropods. [Display omitted] • There are interspecific differences in the abundance of microplastics (MPs). • There is a correlation between MPs abundance and weight in sessile group. • The average number of MPs in N. exigua is 0.00 ± 0.00. • The radulae of N. radula can envelop MPs. • The MPs characteristics between sessile groups are more similar than those between gastropods. [ABSTRACT FROM AUTHOR]

Microbial spoilage of pasteurized fluid milk is typically due to either (1) postpasteurization contamination (PPC) with psychrotolerant gram-negative bacteria (predominantly Pseudomonas) or (2) growth of psychrotolerant sporeformers (e.g., Paenibacillus) that have the ability to survive pasteurization when present as spores in raw milk, and to subsequently grow at refrigeration temperatures. While fluid milk quality has improved over the last several decades, continued reduction of PPC is hampered by the lack of rapid, sensitive, and specific methods that allow for detection of PPC in fluid milk, with fluid milk processors still often using time-consuming methods (e.g., Moseley keeping quality test). The goal of this project was to utilize a set of commercial fluid milk samples that are characterized by a mixture of samples with PPC due to psychrotolerant gram-negative bacteria and samples with presence and growth of psychrotolerant sporeforming bacteria to evaluate different approaches for rapid detection of PPC. Comprehensive microbiological shelf-life characterization of 105 pasteurized fluid milk samples obtained from 20 dairy processing plants showed that 60/105 samples reached bacterial counts >20,000 cfu/mL over the shelf-life due to PPC with gram-negative bacteria. Among these 60 samples with evidence of gram-negative PPC spoilage over the shelflife, 100% (60/60) showed evidence of contamination with noncoliform, non-Enterobacteriaceae (EB) gramnegative bacteria (e.g., Pseudomonas), 20% (12/60) showed evidence of contamination with coliforms, and 7% (4/60) showed evidence of contamination with noncoliform EB. Among the remaining 45 samples, 28 showed levels of gram-positive bacteria above 20,000 cfu/mL and the remaining 17 samples did not exceed 20,000 cfu/mL over the shelf-life. Evaluation of the same set of 105 samples using 6 different approaches {all possible combinations of 2 different enrichment protocols (13°C or 21°C for 18 h) and 3 different plating media [crystal violet tetrazolium agar, EB Petrifilm (3M, St. Paul, MN), and Coliform Petrifilm]} showed that enrichment at 21°C for 18 h, followed by plating on crystal violet tetrazolium agar provided for the most sensitive, accelerated detection of samples that reached >20,000 cfu/mL due to PPC with psychrotolerant gram-negatives (70% sensitivity). These results show that tests still required and traditionally used in the dairy industry (e.g., coliform testing) are not suitable for monitoring for PPC. Rather, approaches that allow for detection of all gram-negative bacteria are essential for improved detection of PPC in fluid milk. [ABSTRACT FROM AUTHOR]

This study assessed the microplastic contamination of 3 most abundant sessile and intertidal invertebrates (Rock Oyster: Saccostrea forskalii, Striped Barnacle: Balanus amphitrite , Periwinkle: Littoraria sp.) in 3 beaches of the eastern coasts of Thailand. The results showed a significant accumulation of microplastics in the invertebrates at rates of 0.2–0.6 counts/g indicating higher pollution levels along the coastline. Filter feeding organisms showed comparatively higher accumulation rates of microplastics. Thus, contaminated bivalves pose potential health risks for seafood consumers. The plastic pollutant prevalence in sessile and intertidal communities was corresponded with pollution characteristics of contaminated beach habitats where they live. Thus, bivalves, gastropods and barnacles can be used as indicators for contamination of microplastics in the areas. This study also demonstrated the need for controlling plastic pollution in Thai coastal areas. [ABSTRACT FROM AUTHOR]

Main objective of the study was the description of Weighted Average Analysis (WAA) as appropriate mathematical method for modelling the demands of freshwater molluscs on their habitats. With this approach site-specific environmental factors defining a certainbiotope are weighted by the related population density of a selected organism. This allows the determination of optimum ranges of physical and chemical factors, within which highest probabilities of occurrence of the investigated organism may be expected. As an exemplary case ecological demands of the Austrian spring snail, Bythinella austriaca, were modelled by using WAA. In addition, a global marginality coefficient, which reflects the ability of the gastropod to occupy ecological niches, and a global tolerance coefficient, describing the width of the niche colonized by the organism, were computed for 10 selected environmental factors. As suggested by the modelling results, B. austriaca exhibits specialist behaviour with regard to water temperature, electric conductivity, dissolved oxygen, total water hardness, geographic altitude, biological oxygen demand, current velocity, and dissolved nitrate. Furthermore, the gastropod only tolerates small to intermediate fluctuations of these environmental factors, which remarkably reduces its ability to act as a pioneer species.