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Aims Determine efficacy of an aqueous photocatalytic disinfection system, photoClO2, against two human norovirus surrogates [feline calicivirus (FCV) and Tulane virus (TuV)] and Clostridioides difficile endospores on stainless steel and nylon carpet. Methods and results The photoClO2 system was first optimized with 1% sodium chlorite (NaClO2) and 10 ppm Eosin Y to produce 60.64 ppm ClO2/min in a 4.5 × 4.5 cm2 area. It was then tested against FCV, TuV, and C. difficile endospores on stainless steel and nylon carpet with two different backings. On stainless steel, photoClO2 achieved a > 5 log10 plaque-forming unit (PFU) reduction of FCV in 45 min, >3 log10 median tissue culture infectious dose (TCID50) reduction of TuV in 60 min, and 1.3 log10 colony-forming unit (CFU) reduction of C. difficile endospores in 120 min. Under indoor lighting conditions, photoClO2 achieved a 4.3 log10 PFU reduction of FCV and 1.4 log10 TCID50 reduction of TuV on stainless steel after 120 min. Further, photoClO2 achieved a 2.9 log10 PFU reduction of FCV and 2.5 log10 TCID50 reduction of TuV on nylon carpet with waterproof backing in 60 min, which was higher than carpet with water-permeable backing (1.3 log10 PFU and 1.1 log10 TCID50 reduction, respectively). Conclusion ClO2 production rate of the photoClO2 system was influenced by light distribution, while disinfection efficacy was affected by light intensity, surface characteristics, and target microorganisms. PhotoClO2 was efficacious in inactivating both human norovirus surrogates on stainless steel and nylon carpet. Efficacy against C. difficile endospores was limited. [ABSTRACT FROM AUTHOR]

The food industry has incurred substantial losses from contamination by Pseudomonas fluorescens, emphasizing the critical importance of implementing effective control strategies. Phages are potential sterilizers due to their specific killing abilities and the difficulty bacteria face in developing resistance. However, a significant barrier to their development is the lack of diversity among phage types. In this study, we characterized a novel lytic P. fluorescens phage, named vB_PF_Y1-MI. Phage vB_PF_Y1-MI displayed a latent period of nearly 10 min and a high burst size of 1493 PFU/cell. This phage showed good activity over a wide range of temperature (up to 70 °C) and pH (3–12). The genome of phage vB_PF_Y1-MI spans 93,233 bp with a GC content of 45%. It encompasses 174 open-reading frames and 19 tRNA genes, while no lysogeny or virulence-associated genes were detected. Phylogenetic analysis positions it as a novel unassigned evolutionary lineage within the Caudoviricetes class among related dsDNA phages. Our study provides foundational insights into vB_PF_Y1-MI and emphasizes its potential as an effective biological control agent against P. fluorescens. This research offers crucial theoretical groundwork and technical support for subsequent efforts in preventing and controlling P. fluorescens contamination. [ABSTRACT FROM AUTHOR]

Nono is a traditional cultured dairy product consumed across West Africa. In this study, five cultures isolated from Nigerian-produced nono and three purified lactic acid bacteria from the USDA-NRRL were examined for use in preparing nono starter cultures. Isolated cultures were characterized using microbiological and biochemical tests, including 16s rDNA sequencing to identify the genotype. Each isolated strain was cultured and inoculated into UHT milk (1% v/v) and allowed to ferment for 24 h at 25 °C. Fermented products were evaluated for pH, moisture content, water activity, and viscosity, and their descriptive sensory properties were noted. The isolate that resulted in sensory properties most similar to traditional nono was then used as the primary strain for subsequent starter culture blends made with the NRRL cultures. These blends were used for the fermentation of nono and compared with commercial nono samples. Isolates obtained from nono were as follows: Lactobacillus fermentum, Lactobacillus paracasei, and, surprisingly, Lactobacillus rhamnosus, which has not been previously reported as a part of the nono microflora. There was no significant difference in the physical parameters of nono made from the individual indigenous isolates and a similar pattern was observed for the organisms from NRRL, except that their total titratable acidity and viscosities were significantly (p < 0.05) higher than those of the indigenous organisms. Compounded starter made with L. rhamnosus and NRRL cultures was then used to make nono that showed significantly (p < 0.05) different pH and viscosity values than commercially purchased nono, while sensory evaluation showed that nono made from the new starter culture had a high overall consumer acceptance score. [ABSTRACT FROM AUTHOR]

Halal means permissible according to Islamic law. Halal meat is obtained by hand slaughtering an animal that is not stunned and that is blessed by a Muslim individual immediately before slaughter. The purpose of this study was to determine the microbiological quality of raw meat from halal meat markets. A total of 138 beef samples were purchased from three halal (n = 72 samples) and three non-halal markets (n = 66 samples) between November 2016 and October 2017. All samples were analyzed for the presence of indicator organisms—aerobic plate counts (APCs), Enterobacteriaceae counts (ECs), total coliform counts (TCCs), and generic Escherichia coli (ECCs). The levels of APCs, ECs, TCCs, and ECCs (mean log CFU/g) in halal samples were 4.93 (100%), 2.89 (91.7%), 2.87 (94.4%), and 1.09 (18.1%), respectively, and those in non-halal samples were 4.92 (100%), 3.07 (95.5%), 3.02 (89.4%), and 1.15 (16.7%), respectively. The levels of TCCs and ECs were higher in halal samples during the summer compared to the other three seasons, whereas the highest ECCs in halal samples were found during autumn. In non-halal samples, significant differences were observed in the ECCs, TCCs, and ECs across seasons, with the highest level of contamination during autumn. Samples having higher levels of indicator organisms (APCs, ECs, TCCs, and ECCs) were more likely to be positive for pathogenic bacteria. The high levels of indicator organisms in both halal and non-halal retail meat samples suggest that the operation size, and not halal or non-halal meat classification, is associated with the microbiological quality. These findings can inform food safety interventions targeting small meat markets in the United States. [ABSTRACT FROM AUTHOR]

Background: Coronaviruses, a group of highly transmissible and potentially pathogenic viruses, can be transmitted indirectly to humans via fomites. To date, no study has investigated their persistence on carpet fibers. Establishing persistence is essential before testing the efficacy of a disinfectant. Methods: The persistence of BCoV and HCoV OC43 on polyethylene terephthalate (PET) and nylon carpet was first determined using infectivity and RT-qPCR assays. Then, the disinfectant efficacy of steam vapor was evaluated against both coronaviruses on nylon carpet. Results: Immediately after inoculation of carpet coupons, 32.50% of BCoV and 3.87% of HCoV OC43 were recovered from PET carpet, compared to 34.86% of BCoV and 24.37% of HCoV OC43 recovered from nylon carpet. After incubation at room temperature for 1 h, BCoV and HCoV OC43 showed a 3.6 and > 2.8 log10 TCID50 reduction on PET carpet, and a 0.6 and 1.8 log10 TCID50 reduction on nylon carpet. Based on first-order decay kinetics, the whole gRNA of BCoV and HCoV OC43 were stable with k values of 1.19 and 0.67 h− 1 on PET carpet and 0.86 and 0.27 h− 1 on nylon carpet, respectively. A 15-s steam vapor treatment achieved a > 3.0 log10 TCID50 reduction of BCoV and > 3.2 log10 TCID50 reduction of HCoV OC43 on nylon carpet. Conclusion: BCoV was more resistant to desiccation on both carpet types than HCoV OC43. Both viruses lost infectivity quicker on PET carpet than on nylon carpet. Steam vapor inactivated both coronaviruses on nylon carpet within 15 s. [ABSTRACT FROM AUTHOR]

The paper develops a multiple matching attenuation method based on extended filtering in the curvelet domain, which combines the traditional Wiener filtering method with the matching attenuation method in curvelet domain. Firstly, the method uses the predicted multiple data to generate the Hilbert transform records, time derivative records and time derivative records of Hilbert transform. Then, the above records are transformed into the curvelet domain and multiple matching attenuation based on least squares extended filtering is performed. Finally, the attenuation results are transformed back into the time-space domain. Tests on the model data and field data show that the method proposed in the paper effectively suppress the multiples while preserving the primaries well. Furthermore, it has higher accuracy in eliminating multiple reflections, which is more suitable for the multiple attenuation tasks in the areas with complex structures compared to the time-space domain extended filtering method and the conventional curvelet transform method. [ABSTRACT FROM AUTHOR]

Simple Summary: Necrotic enteritis is a serious disease in chickens caused by bacterium Clostridium perfringens, leading to high death rates, poor growth, and an economic loss of $6 billion annually worldwide. Currently, antibiotics are commonly used to treat the disease in chickens. However, the rise in antibiotic-resistant bacteria and the growing demand for antibiotic-free poultry products highlights the need to explore sustainable alternatives. Our study investigated natural products of Nigella sativa (black cumin) and authentic kefir as sustainable options in reducing necrotic enteritis in chickens. An animal trial was conducted in which chickens were fed 5% black cumin seeds in their feed, 20% kefir in drinking water, and a combination of both during disease. The results showed that black cumin seeds, kefir, and their combination treatments did not have a detrimental impact on the growth of the chickens and successfully reduced infection and death rates, with the combination being the most effective. Therefore, Nigella sativa, kefir, and their combination can be used as sustainable alternatives to antibiotics in mitigating necrotic enteritis in chickens. Coccidiosis and necrotic enteritis (NE) are prevalent poultry ailments worldwide, leading to decreased live performance and elevated mortality rates without antibiotic usage. This study evaluated Nigella sativa (black cumin) seeds (BCS) and kefir as alternatives to antibiotics for broilers. An in vivo study over a 28-day period, using 384 Cobb 500 male broilers organized into six treatment groups as part of a completely randomized block experimental design was conducted. Each treatment group included eight replicates, with each replicate containing eight birds. The treatments included positive control, negative control, antibiotic control, 5% BCS in feed, 20% kefir in drinking water, and a combination of 5% BCS and 20% kefir. NE was induced in broilers by administering ~5000 oocysts of Eimeria maxima orally on day 14, followed by inoculation with about 108 CFU/mL of Clostridium perfringens (Cp) (strain Cp#4) on days 19, 20, and 21. Live performance metrics including feed intake, body weight gain, and feed conversion were assessed in broilers. Additionally, NE disease outcomes such as lesion scores, mortality rates, and Cp populations in cecum were determined during the study. The BCS, kefir, and the combination had no detrimental effect on broiler live performance. BCS-treated and combination groups had lower NE scores (p > 0.05) in comparison to the positive control and exhibited no significant difference (p > 0.05) from antibiotic control. Additionally, treatment groups and antibiotic control were not significantly different (p > 0.05) in mortality, whereas the BCS and kefir combination significantly reduced (p < 0.05) mortality to 14.1% compared to 31.3% for the positive control. C. perfringens vegetative cells significantly decreased (p < 0.05) in treatments with BCS, kefir, and their combination on days 22 and 28 compared to the positive control. On day 22, Cp sores were significantly lower (p < 0.05) for the kefir and combination treatments compared to the positive control. In conclusion, BCS and kefir successfully reduced C. perfringens infection and mortality without any detrimental impact on broiler live performance with the combined treatment being the most effective. These results suggest that BCS and kefir could serve as potential alternatives to antibiotics in managing NE. [ABSTRACT FROM AUTHOR]

Cross laminated timber (CLT) and glue laminated timber (glulam or GLT) are gaining attention given their use in high-rise buildings as climate mitigation concept. In most cases softwood is used to manufacture these engineered wood products, yet fast-growing and widespread hardwood species such as hybrid poplar have potential to meet the increasing demand. In addition to the mechanical performance, it is also key to investigate the fungal susceptibility and moisture dynamics of poplar, to gain insight into the service life of engineered poplar products. This paper therefore investigates the fungal decay resistance, as well as the moisture sorption properties of (thermally modified) hybrid poplar clones and Norway spruce. Fungal decay resistance was tested using the mini-block test. Moisture dynamics were evaluated using a floating test and dynamic vapor sorption (DVS). A higher fungal decay resistance and a significant decrease of moisture sorption was observed for thermally modified poplar. Our results show that the overall moisture properties of poplar and spruce are similar and that differences among the poplar clones are negligible, demonstrating the potential of poplar wood for engineered wood products. Together with findings on the mechanical properties in the literature, these results on durability and moisture performance give extra support for the potential utilization of poplar CLT in constructions. [ABSTRACT FROM AUTHOR]

Background: Animal manure-based compost is a valuable organic fertilizer and biological soil amendment. To ensure the microbiological safety of compost products, the effectiveness of competitive exclusion microorganisms (CE) in reducing Escherichia coli O157:H7 in dairy manure-based compost was evaluated. Methods: A cocktail of E. coli O157:H7 strains were inoculated into dairy compost along with CE strains isolated from compost, and the reduction in E. coli O157:H7 by CE was determined in compost with 20%, 30%, and 40% moisture levels at 22 °C and 30 °C under laboratory conditions, as well as in fall, winter, and summer seasons under greenhouse settings. Results: Under lab conditions, CE addition resulted in 1.1–3.36 log reductions in E. coli O157:H7 in compost, with enhanced pathogen reduction by higher moisture and lower temperature. In the greenhouse, >99% of the E. coli O157:H7 population in compost with ≥30% moisture due to cross-contamination can be effectively inactivated by CE within 2 days during colder seasons. However, it took ≥8 days to achieve the same level of reduction for heat-adapted E. coli O157:H7 cells. Conclusions: Our results demonstrated that the competitive exclusion of microorganisms can be an effective tool for controlling foodborne pathogens in compost and reducing the potential for soil and crop contamination. [ABSTRACT FROM AUTHOR]

Versatile printing of polymers, metals, and composites always calls for simple, economic approaches. Here we present an approach to three-dimensional (3D) printing of polymeric, metallic, and composite materials at room conditions, based on the polymeric vapor-induced phase separation (VIPS) process. During VIPS 3D printing (VIPS-3DP), a dissolved polymer-based ink is deposited in an environment where nebulized non-solvent is present, inducing the low-volatility solvent to be extracted from the filament in a controllable manner due to its higher chemical affinity with the non-solvent used. The polymeric phase is hardened in situ as a result of the induced phase separation process. The low volatility of the solvent enables its reclamation after the printing process, significantly reducing its environmental footprint. We first demonstrate the use of VIPS-3DP for polymer printing, showcasing its potential in printing intricate structures. We further extend VIPS-3DP to the deposition of polymer-based metallic inks or composite powder-laden polymeric inks, which become metallic parts or composites after a thermal cycle is applied. Furthermore, spatially tunable porous structures and functionally graded parts are printed by using the printing path to set the inter-filament porosity as well as an inorganic space-holder as an intra-filament porogen. The extrusion-based three-dimensional printing of polymers, metals, and composites requires elevated temperatures and may lead to diverse undesirable defects on printed parts. Here, the authors develop a vapor-induced phase separation printing technique to construct polymeric, metallic, and composite parts by using a polymer as a binder. [ABSTRACT FROM AUTHOR]

Poplar has been gaining attention as a potential material for use in engineered wood products (EWPs). However, poplar wood is not durable against fungal degradation, which is an important factor that needs to be investigated. Previous studies on degradation have mostly focused on evaluating mass loss (ML), while lacking information on the progress of degradation. In this study a recently developed non-destructive X-ray computed tomography (CT) technique was used to investigate the degradation progress within poplar, thermally modified (TM) poplar, and spruce during a 10-weeks fungal degradation experiment. The results showed that degradation led to a significant decrease in density, particularly after 15 days. Based on the X-ray CT scans, it was observed that spruce showed a higher mass loss at the end grain while poplar showed a homogeneous pattern throughout the entire block. Thermally modified poplar specimens were less degraded even at moist conditions. The density of the wood was found to affect the fungal susceptibility of both poplar and TM poplar: a higher density resulted in a lower mass loss of poplar. The use of X-ray CT scanning allowed for a detailed micro-level insight into fungal decay, which can potentially help in protecting poplar in future industrial use for constructions. [ABSTRACT FROM AUTHOR]

Antimicrobial coatings can inhibit the transmission of infectious diseases when they provide a quick kill that is achieved long after the coating application. Here, we describe the fabrication and testing of a glass coating containing Ag2O microparticles that was prepared from sodium silicate at room temperature. The half-lives of both methicillin-resistant Staphylococcus aureus (MRSA) and Pseudomonas aeruginosa on this coating are only 2–4 min. The half-life of Clostridioides difficile spores is about 9–12 min, which is extremely short for a spore. Additional tests on MRSA demonstrate that the coating retains its antimicrobial activity after abrasion and that an increased loading of Ag2O leads to a shorter half-life. This coating combines the properties of optical transparency, robustness, fast kill, and room temperature preparation that are highly desirable for an antimicrobial coating. [ABSTRACT FROM AUTHOR]

Biological soil amendments of animal origin (BSAAO), such as animal waste or animal-waste-based composts, may contain foodborne pathogens such as Listeria monocytogenes. Due to the ubiquitous nature of Listeria, it is essential to understand the behavior of L. monocytogenes in BSAAO in order to develop preharvest prevention strategies to reduce pathogen contamination. As biological control agents, competitive exclusion (CE) microorganisms have been widely utilized in agriculture to control plant- or foodborne pathogens. Due to the diverse microbial community, animal wastes and composts are the potential sources for isolating CE strains for pathogen control. To explore the potential of using CE to control L. monocytogenes in BSAAO, we thoroughly reviewed the studies on the fate of L. monocytogenes in the agriculture field, and in the isolation and identification of CE from different matrices, and the applications of CE as a biological control method. Future studies using a next-generation sequencing approach to identify and characterize CE strains in complex microbial communities can provide a comprehensive picture of the microbial interactions between invading pathogens and the indigenous microbiota in BSAAO. This comprehensive review will provide insight into the development of effective biological control measures for preventing L. monocytogenes contamination in the agricultural field and enhancing food safety. [ABSTRACT FROM AUTHOR]

Aim: To isolate the slow‐growing or viable but non‐culturable competitive exclusion (CE) microorganisms from composts and then verify the anti‐Listeria monocytogenes activities of those CE isolates in compost. Methods and Results: CE strains were isolated from composts using double‐ or triple‐layer agar methods, purified, and then characterized. Both compost extracts and solid compost samples were spiked with a cocktail of 3 L. monocytogenes strains which were co‐inoculated with or without CE strain cocktail and incubated at both 22 and 35°C for 168 h. Results indicated that the addition of resuscitation promoting factor (Rpf) promoted the growth of slow‐growing species from composts. About 50% of the isolated CE strains (n = 40) were identified as Bacillus spp., 17 strains can inhibit more than 10 tested L. monocytogenes strains, and nine strains were motile and competitive biofilm formers. In compost extracts, the growth potentials of L. monocytogenes were reduced up to 2.2 logs when co‐culturing with CE strains. In compost samples, the addition of CE strains reduced L. monocytogenes population by ca. 1.3 log CFU/g at 22°C after 24–168 h incubation. Conclusion: Our modified double/triple‐layer agar procedure with Rpf as growth supplement coupled with spot‐on‐lawn testing can be a quick and efficient method for isolating CE candidates from composts. The efficacy of CE strains against L. monocytogenes in compost extracts and compost samples was affected by compost type, nutrient level, and incubation temperature. Significance and Impact of the Study: Compost is a rich source of CE microorganisms, and compost‐adapted CE microorganisms have the potential as a biological agent to control L. monocytogenes in agricultural environments. [ABSTRACT FROM AUTHOR]

Aims: To determine the efficacy of a panel of nine EPA‐registered disinfectants against two human norovirus (HuNoV) surrogates (feline calicivirus [FCV] and Tulane virus [TuV]) and Clostridioides difficile endospores. Methods and Results: Nine EPA‐registered products, five of which contained H2O2 as active ingredient, were tested against infectious FCV, TuV and C. difficile endospores using two ASTM methods, a suspension and carrier test. Efficacy claims against FCV were confirmed for 8 of 9 products. The most efficacious product containing H2O2 as ingredient achieved a >5.1 log reduction of FCV and >3.1 log reduction of TuV after 5 min, and >6.0 log reduction of C. difficile endospores after 10 min. Of the five products containing H2O2, no strong correlation (R2 = 0.25, p = 0.03) was observed between disinfection efficacy and H2O2 concentration. Addition of 0.025% ferrous sulphate to 1% H2O2 solution improved efficacy against FCV, TuV and C. difficile. Conclusion: Disinfectants containing H2O2 are the most efficacious disinfection products against FCV, TuV and C. difficile endospores. Product formulation, rather than the concentration of H2O2 in a product, impacts the efficacy of a disinfection product. Significance and Impact of Study: H2O2‐based disinfectants are efficacious against surrogate viruses for HuNoV and C. difficile endospores. Significance and Impact of Study: H2O2‐based disinfectants are efficacious against surrogate viruses for HuNoV and C. difficile endospores. [ABSTRACT FROM AUTHOR]

Sorghum [Sorghum bicolor (L.) Moench] is a common feed grain globally with vast genetic and phytochemical diversity that may provide numerous health benefits, including its aptitude as an antimicrobial feed grain. This study highlights the antimicrobial potential of a collection of 384 diverse sorghum accessions against two prominent foodborne pathogens, Clostridium perfringens and Salmonella enterica. Following extensive screening, we determined that sorghum grain extract is more efficient at inhibiting C. perfringens than S. enterica. Antimicrobial activity observed against C. perfringens was not significantly correlated with either total phenols (r = 0.12) or tannin concentration (r = 0.12). Moreover, we mapped loci associated with antimicrobial activity to C. perfringens that are independent of loci associated with total phenols and tannins. The two most significant associations were determined to have an epistatic interaction and 20 candidate genes were identified. By sequence homology studies, we found the potential functions of these candidates to include plant stress response (Sobic.002G083600) and phenol metabolism regulation (Sobic.010G222600). Additionally, we noted no relationship between antimicrobial activity and either grain yield or composition. These results highlight significant heritable variation of antimicrobial activity in sorghum that may be useful for breeding to improve its value as a feed source by incorporating grain‐based antibiotics in animal production. [ABSTRACT FROM AUTHOR]

The aim of this study was to compare and model the thermal inactivation of bacteriophages as surrogates for pathogenic viruses, such as avian influenza virus, in chicken litter compost. Three bacteriophages [ø6, MS2, and Felix O1 (FO)] were inoculated separately into aged chicken litter compost with various moisture contents (MCs), and then exposed to 75 and 85 °C for up to 3 h. The bacteriophage ø6 was undetectable during come-up time at all tested conditions. After 3 h heat treatment at 75 °C, population reductions of MS2 in the compost with 20, 30, and 40% MCs were 5.83, 6.08, and 8.32 log plaque forming units (PFU g−1), respectively, as compared with 4.87, 5.40, and 5.75 log PFU g−1 for FO, respectively. When exposed to 85 °C, population reductions of MS2 in the compost with 20, 30, and 40% MCs were 6.07, 7.93, and 8.03 log PFU g−1, respectively, as compared with 6.29, 6.20, and 7.59 log PFU g−1 for FO, respectively. Both bacteriophages MS2 and FO had higher recovery rates from compost, and bacteriophage MS2 had a comparable thermal resistance with the reported resistance of avian influenza virus than bacteriophage FO. Additionally, the proposed non-linear three-phase model was developed to describe the survival of bacteriophages exposed to the physical-heat treatment into different stages. Considering that virus may survive in some cold spots of compost piles, this study provides scientific evidence for the fertilizer industry to validate the effectiveness of their heating process in order to inactivate avian influenza virus in chicken litter compost. [ABSTRACT FROM AUTHOR]

Compost is organic material that has been degraded into a nutrient-stabilized humus-like substance through intense microbial activity, which can provide essential plant nutrients (nitrogen, phosphorus) to aid in the growth of fruits and vegetables. Compost can be generated from animal waste feedstocks; these can contain human pathogens, which can be inactivated through the heat and microbial competition promoted during the composting process. Outbreaks of infections caused by bacterial pathogens such as Escherichia coli O157:H7, Salmonella, and Listeria monocytogenes on fruit and vegetable commodities consumed raw emphasize the importance of minimizing the risk of pathogenic contamination on produce commodities. This review article investigates factors that affect the reduction and survival of bacterial foodborne pathogens during the composting process. Interactions with indigenous microorganisms, carbon:nitrogen ratios, and temperature changes influence pathogen survival, growth, and persistence in finished compost. Understanding the mechanisms of pathogen survival during the composting process and mechanisms that reduce pathogen populations can minimize the risk of pathogen contamination in the cultivation of fruits and vegetables. [ABSTRACT FROM AUTHOR]

Although transmission of human norovirus in food establishments is commonly attributed to consumption of contaminated food, transmission via contaminated environmental surfaces, such as those in bathrooms, may also play a role. Our aim was to determine the prevalence of human norovirus on bathroom surfaces in commercial food establishments in New Jersey, Ohio, and South Carolina under nonoutbreak conditions and to determine characteristics associated with the presence of human norovirus. Food establishments (751) were randomly selected from nine counties in each state. Four surfaces (underside of toilet seat, flush handle of toilet, inner door handle of stall or outer door, and sink faucet handle) were swabbed in male and female bathrooms using premoistened macrofoam swabs. A checklist was used to collect information about the characteristics, materials, and mechanisms of objects in bathrooms. In total, 61 (1.5%) of 4,163 swabs tested were presumptively positive for human norovirus, 9 of which were confirmed by sequencing. Some factors associated with the presence of human norovirus included being from South Carolina (odd ratio [OR], 2.4; 95% confidence interval [CI], 1.2 to 4.9; P < 0.05) or New Jersey (OR, 1.7; 95% CI, 0.9 to 3.3; 0.05 < P < 0.10), being a chain establishment (OR, 1.9; 95% CI, 1.1 to 3.3; P < 0.05), being a unisex bathroom (versus male: OR, 2.0; 95% CI, 0.9 to 4.1; 0.05 < P < 0.10; versus female: OR, 2.6; 95% CI, 1.2 to 5.7; P < 0.05), having a touchless outer door handle (OR, 3.3; 95% CI, 0.79 to 13.63; 0.05 < P < 0.10), and having an automatic flush toilet (OR, 2.5, 95% CI, 1.1 to 5.3; 0.05 < P < 0.10). Our findings confirm that the presence of human norovirus on bathroom surfaces in commercial food establishments under nonoutbreak conditions is a rare event. Therefore, routine environmental monitoring for human norovirus contamination during nonoutbreak periods is not an efficient method of monitoring norovirus infection risk. [ABSTRACT FROM AUTHOR]

Effect of high pressure (HP) treatment (200–600 MPa; 0–20 min) on quality of fresh-cut carrot slices was evaluated after presoaking in selected calcium salt solutions (1% calcium chloride, 1% calcium lactate, 1% calcium gluconate, and distilled water as control) for one hour. Results showed that calcium chloride (CaCl2) solution pretreatment was most effective for preserving the hardness of carrot slices at 400 and 600 MPa and this treatment also resulted in the least amount of color change in carrots, followed by calcium lactate, gluconate, and control pretreatments. The average sensory evaluation scores during 9 days of refrigerated storage at 4°C in control, CaCl2, calcium lactate, and calcium gluconate presoaking treatments followed by HP treatment were 6.4 ± 0.5, 8.0 ± 0.5, 7.8 ± 0.4, and 7.6 ± 0.3, respectively, on a zero to 9 scale for quality. [ABSTRACT FROM AUTHOR]

Dairy compost with 20, 30, or 40% moisture content (MC) was inoculated with a mixture of six non-O157 Shiga toxin–producing Escherichia coli (STEC) serovars at a final concentration of 5.1 log CFU/g and then stored at 22 and 4°C for 125 days. Six storage conditions—4°C and 20% MC, 4°C and 30% MC, 4°C and 40% MC, 22°C and 20% MC, 22°C and 30% MC, and 22°C and 40% MC—were investigated for the persistence of non-O157 STEC in the dairy compost. During the entire storage, fluctuations in indigenous mesophilic bacterial levels were observed within the first 28 days of storage. After inoculation, the non-O157 STEC population increased 0.69 and 0.79 log CFU/g in the dairy compost with 30 and 40% MC at 22°C within the first day, respectively; for all other storage conditions, the pathogen population decreased rapidly. After the 125-day storage, the reductions of non-O157 STEC for 4°C and 20% MC, 4°C and 30% MC, 4°C and 40% MC, 22°C and 20% MC, 22°C and 30% MC, and 22°C and 40% MC storage conditions were >4.52, >4.55, 3.89, >4.61, 3.60, and 3.17 log CFU/g, respectively. All the survival curves showed an extensive tail, indicating non-O157 STEC can survive at least for 125 days in the dairy compost. The survival data were analyzed with log-linear with tailing and Weibull models. Compared with the log-linear with tailing model, the Weibull model was found to be a better choice for predicting the survival of non-O157 STEC in dairy compost owing to a high overall R2 value (0.8738 to 0.9909). The decay rate of non-O157 STEC was higher in dairy compost stored at 4°C compared with at 22°C, and the same trend was found for the compost with 40% MC versus 20% MC. In addition, two non-O157 STEC serotypes (STEC O145 and O45) were detected on the last day of the longitudinal study and may deserve special attention in the Big 6 STEC group. Our results have provided scientific data for risk assessment of the microbiological safety of dairy compost to control non-O157 STEC during subsequent storage of dairy compost. [ABSTRACT FROM AUTHOR]

Animal wastes have high nutritional value as biological soil amendments of animal origin for plant cultivation in sustainable agriculture; however, they can be sources of some human pathogens. Although composting is an effective way to reduce pathogen levels in animal wastes, pathogens may still survive under certain conditions and persist in the composted products, which potentially could lead to fresh produce contamination. According to the U.S. Food and Drug Administration Food Safety Modernization Act, alternative treatments are recommended for reducing or eliminating human pathogens in raw animal manure. Physical heat treatments can be considered an effective method to inactivate pathogens in animal wastes. However, microbial inactivation in animal wastes can be affected by many factors, such as composition of animal wastes, type and physiological stage of the tested microorganism, and heat source. Following some current processing guidelines for physical heat treatments may not be adequate for completely eliminating pathogens from animal wastes. Therefore, this article primarily reviews the microbiological safety and economic value of physically heat-treated animal wastes as biological soil amendments. [ABSTRACT FROM AUTHOR]

A microbiological investigation on Salmonella contamination was conducted in two U.S. rendering plants to investigate the potential cross-contamination of Salmonella in the rendering processing environment. Sampling locations were predetermined at the areas where Salmonella contamination may potentially occur, including raw materials receiving, crax (rendered materials before grinding process) grinding, and finished meal loading-out areas. Salmonella was either enumerated directly on xylose lysine Tergitol 4 agar plates or enriched in Rappaport-Vassiliadis and tetrathionate broths. The presumptive Salmonella isolates were confirmed using CHROMagar plating and latex agglutination testing and then characterized using pulsed-field gel electrophoresis, serotyping, and biofilm-forming determination. Among 108 samples analyzed, 79 (73%) samples were Salmonella positive after enrichment. Selected Salmonella isolates (n = 65) were assigned to 31 unique pulsed-field gel electrophoresis patterns, with 16 Salmonella serotypes, including Typhimurium and Mbandaka, identified as predominant serotypes and 10 Salmonella strains determined as strong biofilm formers. Our results indicated that the raw materials receiving area was the primary source of Salmonella and that the surfaces surrounding crax grinding and finished meal loading-out areas harbor Salmonella in biofilms that may recontaminate the finished meals. The same Salmonella serotypes found in both raw materials receiving and the finished meal loading-out areas suggested a potential of cross-contamination between different areas in the rendering processing environment. [ABSTRACT FROM AUTHOR]

Enteric viruses are the most common cause of acute gastroenteritis worldwide with most cases of illness attributed to caliciviruses, such as human noroviruses (HuNoV). While environmental transmission of HuNoV is reported to be low, environmental surfaces could be a source of secondary transmission. As many vomiting/fecal episodes occur in bathrooms, bathroom surfaces could be an important vehicle for transmitting HuNoV. We systematically reviewed the literature to determine the presence of HuNoV on bathroom surfaces. Our review included 22 eligible studies conducted in commercial and institutional settings. Under outbreak conditions, 11 studies reported detection rates of 20–100 %. Six studies implicated bathroom surfaces as primary sources of HuNoV infection while three reported HuNoV present on bathroom surfaces but indicated different primary sources. Under non-outbreak conditions, five studies reported detection rates of 2–17 %. Factors associated with HuNoV presence in bathrooms included population density, setting type, employee numbers, food handler knowledge, awareness, and behaviours, and cleaning/disinfecting procedures. Our review suggests bathrooms could be vehicles that transmit HuNoV under both outbreak and non-outbreak conditions. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Microbiology is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Phytopathogenic microorganisms can produce pectin methylesterase (PME) to degrade plant cell walls during plant invasion. This enzyme is thought to be a virulence factor of phytopathogens. In this work, PME from Aspergillus flavus (AFPME) was expressed in Pichia pastoris and an in vitro inhibitor study was performed. The purified AFPME with a yield of 52.2% was resolved as one band with a molecular mass of c. 40 kDa by SDS-PAGE. Optimal activity of the enzyme occurred at a temperature of 55 °C and a pH of 4.8. Epigallocatechin gallate (EGCG) strongly inhibited the activity of recombinant AFPME. The molecular docking analysis indicated that EGCG could form hydrogen bonds and π-π interactions with some amino acid residues in the active site of AFPME. Our studies provide a novel strategy for the control of the plant invasion of A. flavus. [ABSTRACT FROM AUTHOR]

BACKGROUND: Pectin methylesterase (PME) catalyses the hydrolysis of the methyl ester of pectin, yielding free carboxyl groups and methanol. PME is widely used in the food, cosmetic and pharmaceutical industries. RESULTS: PME from Aspergillus niger was constitutively expressed to a high level in the yeast Pichia pastoris. The recombinant PME was purified by a combination of ammonium sulfate fractionation and ion exchange chromatography, giving an overall yield of 28.0%. It appeared as a single band in sodium dodecyl sulfate polyacrylamide gel electrophoresis, with a molecular mass of about 45 kDa. Optimal activity of the enzyme occurred at a temperature of 50 °C and a pH of 4.7. The Km, Vmax and kcat values of the enzyme with respect to pectin were 8.6 mmol L−1 [ ], 1.376 mmol min−1 mg−1 and 8.26 × 102 s−1 respectively. Cations such as K+, Mg2+, Ni2+, Mn2+ and Co2+ slightly inhibited its activity, whereas Na+ had no effect. CONCLUSION: PME from A. niger was constitutively expressed to a high level in P. pastoris without methanol induction. The recombinant PME was purified and characterised and shown to be a good candidate for potential application in the fruit juice industry. Copyright © 2012 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Microbiology is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This review focuses on applying nanotechnology to foodborne pathogen detection. Because of low infectious doses for most foodborne pathogens, the rapid and sensitive detection methods are essential to ensure the food safety. The advances in the development of nanomaterials have stimulated worldwide research interests in their applications for bioanalysis. The conjugation of biomolecules with nanomaterials is the foundation of nano-biorecognition. A variety of strategies including antibody–antigen, adhesin–receptor, antibiotic, and complementary DNA sequence recognitions have been explored for specific recognition between target bacterial cells and bio-functionalized nanomaterials. The incorporation of these bio-functionalized nanomaterials into current pathogen detection methods has led to rapid and nearly real-time pathogen detection (as short as a few minutes), improved sensitivity (single bacterial cell), and simultaneous detection of multiple micro-organisms from either nutrient broth, liquid or solid food products, or biofilms. The unique properties of nanomaterials in physical strength, chemical reactivity, electrical conductance, magnetism and optical effects make them promising in the development of practical biosensors with emphasis on device portability and simplicity in sample preparation, and the improvement of current pathogen detection methods. [ABSTRACT FROM AUTHOR]

The survival and growth of Listeria monocytogenes in soil amended with bovine manure was studied under different environmental conditions of temperature, nutrients, and soil microftora. Autoclaved soil was compared with unautoclaved soil for assessing the influence of competitive soil microflora on the survival of L. monocytogenes. Initial L. monocytogenes cell numbers of 5 to 6 log CFU/g survived for up to 43, 43, and 14 days in manure-amended autoclaved soil at 5, 15, and 21°C, respectively. In manure-amended unautoclaved soil, the pathogen was detectable for up to 43, 21, and 21 days at 5, 15, and 21°C, respectively. L. monocytogenes was inactivated more rapidly in autoclaved soil amended with manure at a manure/soil ratio of 1:10 than in the more dilute (1:100) manure in soil samples at both 15 and 21°C. However, in manure-amended unautoclaved soil, L. monocytogenes survived longer in samples with ratios of 1:10 than in the more dilute (1:100) manure-amended soil. The persistence of L. monocytogenes for several weeks in manure-amended soil suggests listeriae could be transmitted through soil to fresh produce or to shoes, clothing, and hands of field workers, especially during the cold months. [ABSTRACT FROM AUTHOR]

The heavy chain (Hc) and light chain (Lc) genes of the Fab fragment of a catalytic antibody 6D9 were simultaneously expressed in an Escherichia coli in vitro transcription/translation system without a reducing agent. The intermolecular disulfide bond between the Hc and Lc was found formed, suggesting a correct formation of the Fab fragment in the in vitro system. In enzyme-linked immunosorbent assay, the Fab fragment synthesized in vitro exhibited an antigen-binding activity. Addition of reduced glutathione, oxidized glutathione, protein disulfide-isomerase and molecular chaperones, GroEL and GroES, increased the solubility and the antigen-binding activity of the Fab fragment greatly. The in vitro synthesized Fab was purified by means of a hexa-histidine tag attached to the C-terminus of the Hc. Catalytic assay of the purified Fab fragment showed that the His-tagged Fab fragment synthesized in vitro had a catalytic activity comparable to that produced in vivo. [Copyright &y& Elsevier]