Mérieux NutriSciences offers practical testing, auditing, consulting, training, and research solutions to meet the needs of manufacturers, food processors, caterers and retailers. The company is legally headquartered in Chicago. A subsidiary of Institut Mérieux, Mérieux NutriSciences employs more than 8000 employees in 27 countries.
This study investigated the thermal inactivation kinetics of three pathogens, Salmonella, Escherichia coli, Listeria monocytogenes, and a surrogate microorganism Enterococcus faecium during oil frying of potato pellets at varying moisture contents of 5.4, 10.0, and 14.4%. Thermal treatments were conducted across temperatures ranging from 80 to 108 °C to establish comparative heat resistance profiles. Experimental results demonstrated that Salmonella exhibited superior thermal resistance compared to both E. coli and L. monocytogenes. At 14.4% moisture content, Salmonella D-values were determined to be 1.93, 0.85, and 0.45 min at 88 ,92 , and 96 °C, respectively. When moisture content was reduced to 5.4%, Salmonella displayed increased thermal resistance, with D-values of 2.38, 1.2, and 0.72 min at 89, 92, and 98 °C. Notably, E. faecium emerged as the most heat-resistant microorganism among all tested species, exhibiting D-values of 1.06, 0.65, and 0.31 min at 98, 103, and 108 °C in 5.4% moisture samples. Comparative analysis revealed that E. faecium demonstrated 1.6-fold greater heat resistance than Salmonella at 5.4% moisture, and 2.8- to 5.4-fold greater resistance at 14.4% moisture across 90-110 °C. Verification testing at 129 °C with 10.6% moisture content resulted in population reductions of 4.73 and 5.6 log CFU/g for E. faecium and Salmonella, respectively, after 6 seconds of treatment. These findings provide a scientific foundation for validation protocols in similar fried, low-moisture food products and substantiate the potential application of E. faecium as a suitable surrogate organism for in-plant validation studies of fried, low-moisture products such as potato pellets.
Nitrous oxide (N2O) is a widely used anesthetic; however, its potential to compromise genomic stability by disrupting vitamin B12 and folate metabolism remains a critical concern in clinical molecular biology. Since N2O can oxidize cobalamin, it may theoretically impair the methionine synthase pathway, leading to DNA damage. Thus, this study aimed to evaluate the toxicogenetic impact—DNA damage and gene expression—and the metabolic profile of vitamins B9 and B12, homocysteine (HCY) and micronutrients/antioxidants in patients undergoing short-term N2O anesthesia. Adult surgical patients without comorbidities (n = 18/group) were assessed at: pre-anesthesia, during anesthesia (1.5 h exposure), and 24 h post-anesthesia. Both groups received desflurane, with one also receiving N2O. The primary focus was on DNA strand breaks (comet assay) and the transcriptional levels (RT-qPCR) of repair (OGG1 and XRCC1) and antioxidant (HO-1) genes, followed by HPLC and chemiluminescence analysis of metabolic markers (HCY and antioxidants, vitamins B9 and B12). N2O exposure did not modulate the mRNA expression of any of the studied genes, nor did it alter HCY, vitamin levels or antioxidants (p > 0.05). A transient, group-independent increase in DNA damage was observed post-anesthesia, suggesting a primary response to surgical stress rather than the anesthetic agent. Our study provides high-evidence molecular data demonstrating that 1.5 h of N2O exposure is safe for genomic integrity and vitamin B-related metabolism in healthy individuals. These findings are clinically relevant as they validate the continued use of N2O in minimally invasive procedures without the risk of acute toxicogenetic or metabolic impairment.
ABSTRACT Listeria swaminathanii UTK S2-0008, isolated from soil collected in the Nantahala National Forest in North Carolina, USA, is the only L. swaminathanii strain eligible to serve as the type strain, which is needed to achieve valid status. The previously effectively published type, L. swaminathanii FSL L7-0020 T , and previously described strains UTK C1-0015 and UTK C1-0024 do not conform to the International Code of Nomenclature of Prokaryotes’ rules for type strains. Additionally, the currently designated type strain (FSL L7-0020 T = ATCC TSD-239 T ) is an atypical representative of L. swaminathanii as it is the only strain lacking catalase activity. Therefore, it is proposed to reassign the type to L. swaminathanii (UTK S2-0008 T = CCUG 77280 T = LMG 33255 T ). Whole-genome sequence-based average nucleotide identity (ANI) showed that this strain clustered with the three previously described L. swaminathanii strains (FSL L7−0020 = ATCC TSD-239, UTK C1-0015, and UTK C1-0024; pairwise ANI ranged from 98.71% to 98.83%). All four strains, including the one described here, could not be classified as any validly published Listeria species and showed the highest similarity to Listeria marthii (maximum ANI of 93.92%, in silico DNA-DNA hybridization of 56.2%). L. swaminathanii exhibits the phenotypic characteristics that are currently expected of the Listeria sensu stricto species. This species lacks phenotypic characteristics associated with Listeria pathogenicity (non-hemolytic and negative for phosphatidylinositol-specific phospholipase C activity); the genomes lack genes associated with virulence (all genes found on the Listeria pathogenicity island 1 [LIPI-1], as well as the internalin genes inlA and inlB ), which support L. swaminathanii is nonpathogenic. IMPORTANCE The genus Listeria includes species of significant relevance to food safety, environmental microbiology, and public health. Accurate species identification is critical because misidentification of nonpathogenic species as pathogenic ones can lead to unnecessary recalls and regulatory complications. The validation of Listeria swaminathanii sp. nov. will ensure that this species is formally recognized and has a type strain (UTK S2-0008 T ) that is representative of the species. This work strengthens diagnostic accuracy by enabling the inclusion of this species in reference databases and inclusivity studies, reducing the risk of false identification. Furthermore, the identification and characterization of Listeria swaminathanii sp. nov. expands our understanding of the genetic and ecological diversity within the genus Listeria , particularly among soil-dwelling strains.
The current Dutch diet fails to meet existing nutritional guidelines and exceeds the environmental boundaries as defined by the EAT-Lancet Commission. The purpose of this study is to model planet-based diets for the Netherlands for 2030 and 2050 that are in line with national dietary recommendations and within the planetary boundaries, as input for future Food-System Based Dietary Guidelines. Future Dutch planet-based diets were modelled using mathematical optimisation (Optimeal 3.0) with the most recent 2019–2021 food consumption survey for males and females (18–50 years) and the environmental impact database for Dutch foods (2024). Environmental impacts were adjusted to align with the planetary boundaries and incorporate forecasted improvements. Constraints were applied on nutrients and environmental impacts (greenhouse gas emissions in kg CO2eq/y, blue water use in m3/y, cropland use in hectares, phosphorus application and surplus nitrogen in kg/y). The ReCiPe 2016 endpoint indicator method was applied to calculate biodiversity loss related to diets (extinctions/ million species year). The optimised diets resulted in a significant reduction in meat, eggs, fats/oils, potatoes/tubers, and sugar/confectionery, and a significant increase in legumes, nuts/seeds, vegetables, fish, and meat replacers. In the optimised diets, 64
BACKGROUND:Metagenomic next-generation sequencing (mNGS) enables broad, untargeted detection of pathogens and microbial signals across complex sample types. However, the diversity of operational contexts, from regulatory enforcement to exploratory discovery, challenges the defining of analytical or interpretive standards appropriate across all applications. Variability in laboratory practices, bioinformatic methods, and reporting conventions continues to limit consistency and decision-maker confidence in mNGS results. OBJECTIVES:We introduce STRATUM (Structured Framework for Reporting, Assessment, and Translational Utility of Metagenomics), a use-case-stratified framework that aligns quality assurance, metadata reporting, and interpretive standards with the consequence and intended use of metagenomic sequencing outputs. METHODS:STRATUM is organized around five representative biosurveillance use cases spanning public health, food safety, environmental monitoring, synthetic biology detection, and national security. A three-tier interpretive model calibrates analytical rigor, validation expectations, and reporting requirements to decision consequence; from high-consequence regulatory and clinical determinations (Tier 1), through operational surveillance (Tier 2), to exploratory and hypothesis-generating contexts (Tier 3). RESULTS:The framework provides graduated guidance across key domains including sample preparation, sequencing design, controls and contamination governance, reference database curation, bioinformatics reproducibility, and multi-factor signal validation. Cross-cutting principles include explicit documentation of evidentiary bases, transparency in database and pipeline provenance, and defined escalation pathways when results transition between interpretive tiers. CONCLUSION:Realizing the operational potential of mNGS requires evidentiary standards responsive to decision context rather than fixed across applications. STRATUM offers a consequence-tiered model for quality and reporting in applied metagenomics, supporting reproducible, transparent, and defensible sequencing-based surveillance across public health and biodefense domains.
