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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]

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.

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]

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]

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]

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]