International Journal of Food Microbiology

Domestication of molds for cheese production has repeatedly shaped Penicillium fungi, most notably giving rise to the emblematic P. camemberti lineage, derived from P. biforme. Here, we identified a new P. biforme lineage, named cheesy, likely selected from P. biforme for food fermentation, including cheese and sausage production. This lineage exhibits evidence of a severe bottleneck, with little nucleotide polymorphism and a single mating type. The cheesy lineage has evolved advantageous traits for cheesemaking: compared to other P. biforme strains and its wild relative P. fuscoglaucum, it displays faster growth on cheese, galactose and lactose media, higher sporulation and germination rates on cheese, elevated lipolytic activity, enhanced inhibition capacities, and produced specific volatile organic compounds. Additionally, P. camemberti and P. biforme cheesy differ in their content of Starship mobile elements, acquired through horizontal transfers. These elements carry cargo genes potentially relevant for adaptation to cheese. Notably, the cheesy lineage has acquired a 20 kb Starship element (Rattus), nested within a much larger 160 kb Starship (Bilge), and carrying cargo genes with predicted functions involved in antagonistic interactions among micro-organisms. SignificanceO_LIWe identified a new Penicillium biforme lineage, named cheesy, which was likely selected from P. biforme for food fermentation (cheese and sausage), genetically and phenotypically different from the emblematic P. camemberti lineage. This lineage suffered from a severe bottleneck, displaying very little nucleotide polymorphism and a single mating type. C_LIO_LIThis newly identified lineage has evolved advantageous traits for cheesemaking; compared to other P. biforme strains and its wild relative P. fuscoglaucum, it displayed faster growth on cheese, galactose and lactose media, higher sporulation and germination rates on cheese, higher lipolytic activity, better inhibition capacities and specific volatile organic compounds. C_LIO_LIPenicillium camemberti and P. biforme cheesy also differed by their content in Starship mobile elements, acquired through horizontal transfers, and carrying cargo genes potentially relevant for adaptation to cheese. C_LIO_LINotably, the cheesy lineage has acquired a specific 20 kb Starship nested within a much larger 160 kb Starship, and likely involved in antagonistic interactions. C_LI

Romanian bors, a traditional fermented wheat bran beverage, is produced through spontaneous fermentation and represents a complex microbial ecosystem. Despite its cultural importance and presumed health benefits, its microbial ecology and functional potential remain poorly characterized. The present study aimed to elucidate the microbial community structure of bors and link it to functional traits relevant to fermentation performance and food functionality by integrating culture-independent sequencing with culture-dependent isolation and functional characterization. A total of 32 bors samples (12 commercial and 20 homemade) were analyzed. Amplicon-based sequencing revealed a microbiome dominated by lactic acid bacteria (LAB), with lactobacilli accounting for the majority of the bacterial communities and Lactobacillus amylolyticus being identified as the most prevalent and abundant species. The yeast communities were mainly composed of fermentative taxa, including Pichia kudriavzevii and Kluyveromyces marxianus. Lactobacillus amylolyticus and P. kudriavzevii were also the most frequently isolated species among bacteria and yeasts, respectively. These results highlighted a strong adaptation of the microbial isolates to starch-rich cereal substrates and underscored the central role of these microorganisms in wheat bran fermentation for bors production. Whereas the sequencing-based analyses showed no significant differences in overall diversity between the commercial and homemade bors samples, the cultivation-based results indicated a higher bacterial richness in the commercial products. Notably, the culture-dependent method captured substantially fewer taxa, highlighting the complementary nature of the two approaches. Of a total of 101 bacterial strains (88 LAB and 13 acetic acid bacteria) isolated, many exhibited rapid growth and strong acidification capacity, reaching pH values below 4.5 within 12 h. A functional screening revealed that 21 % of these strains displayed -amylase activity, 65 % phytase activity, and 50 % {beta}-glucosidase activity, highlighting their capacity to metabolize cereal substrates and enhance the nutrient availability of bors. All strains showed antibacterial activity against at least one indicator bacterium tested, with a universal inhibition of Listeria monocytogenes. Overall, Romanian bors harbored a lactic acid bacteria-dominated core microbiome with a significant functional diversity. These findings underscored its potential as a rich source of functional and technologically important strains for application in starter and protective culture development.

Salmonella is a pathogen linked to foodborne outbreaks, including low-moisture foods. Its ability to resist desiccation can contribute to the formation of dry surface biofilms (DSB). This study evaluated the impact of 3 DSB formation protocols (P1=48-h hydrated phase/48-h dry phase, P2=24-h/120-h and P3=8-h/48-h) on the resistance of Salmonella DSB to 70% alcohol, a commercial product (based on 0.015% quaternary ammonium and 25% isopropyl alcohol), gaseous ozone (45 ppm), hot air (90 {degrees}C) and UV-C light (254 nm). The type of DSB protocol impacted the efficacy of the sanitizers (p < 0.05). The biofilm with the shortest hydration phase showed the greatest susceptibility; three out of the five sanitizers evaluated (70% alcohol, commercial product, and UV-C) promoted significant reductions in P3, with counts below the detection limit (0.8 log CFU/cm{superscript 2}) after 5 to 15 min exposure. Regarding protocols P1 and P2, in general, the best performance was from UV-C, especially against DSB on polypropylene, where it achieved reductions of 1.3 log CFU/cm{superscript 2} for P1 and 2.9 log CFU/cm{superscript 2} for P2 after 15 to 30 min of exposure. In contrast, hot air and ozone showed less effectiveness, with reductions [&le;]1.2 log CFU/cm{superscript 2}. In most scenarios, confocal microscopy images corroborated the plate count results (log CFU/cm{superscript 2}). In summary, our data indicates limited action of dry sanitizers on Salmonella DSB, requiring validation and optimization of sanitization processes to ensure the microbiological safety of low-moisture products.

Ugba, a traditional alkaline-fermented condiment produced from African oil bean seeds (Pentaclethra macrophylla Benth.), remains poorly characterised at genome resolution. This study characterised a single spontaneous ugba fermentation using genome-resolved shotgun metagenomics across Early (0-24 h), Mid (48-96 h), and Late (120-144 h) composite stages. Thirty metagenome-assembled genomes (MAGs) were recovered and grouped according to their temporal abundance patterns. The Early-stage retained MAG population was dominated by Bacteroidota-associated MAGs, which exhibited the highest carbohydrate-active enzyme density and broad glycoside hydrolase repertoires, consistent with substantial genome-encoded potential for utilisation of the plant-derived seed matrix. The Mid stage showed marked restructuring of MAG composition, while Core and Late-associated MAGs increased towards fermentation maturation. Functional differentiation was also evident among Corynebacterium MAGs: C. nuruki encoded a complete urease system, whereas C. phoceense_A encoded glutamate dehydrogenase and nitrate-reduction genes. These stage-associated changes coincided with progressive alkalinisation from pH 7.15 to 8.01. Together, the results show that temporal restructuring of reconstructed microbial populations was accompanied by differentiation in genome-encoded functional potential. This study provides a genome-resolved characterisation of microbial composition and functional potential during spontaneous ugba fermentation and expands current understanding of the microbial organisation of this traditional African fermented food.

The Bacillus cereus group comprises bacteria of biotechnological interest, but also raises health concerns. Some bacteria in this group are opportunistic human pathogens, mainly causing foodborne gastrointestinal infections. As of today, the presence, sequence variability, or expression of genes encoding toxins or other virulence factors are insufficient to predict the potential of a given isolate to cause the diarrheal form of the disease. To address this limitation, we developed a sandwich ELISA to quantify the NheA and Sphingomyelinase (SMase) proteins in culture supernatants to test them as markers of pathogenic potential. Application of the assay to a collection of B. cereus group isolates revealed that strains associated with food poisoning outbreaks produce significantly more NheA and SMase than those isolated from the environment or from commercial products. Statistical analyses show that the combined quantification of NheA and SMase provides robust discrimination between pathogenic and non-pathogenic (environmental and commercial) profiles. These results demonstrate that the quantitative assessment of both NheA and SMase production can serve as a reliable biomarker for distinguishing diarrheic food poisoning isolates from harmless strains.

Aims Honey represents a distinct microbial habitat, imposing physicochemical stresses on its resident microbiota while also serving as a potential source of beneficial microorganisms. This study aimed to isolate lactic acid bacteria (LAB) from Korean wildflower honey and characterize their gastrointestinal (GI) and physiological stress tolerance, adhesion-related properties, functional characteristics, and safety to evaluate their potential as probiotic candidates. Methods and Results Two Streptococcus salivarius strains, DOW-5A and DOW-10, were isolated from Korean wildflower honey and identified by phenotypic and molecular analyses. Both strains survived in sequential exposure to simulated GI conditions and showed tolerance to physiological stresses. DOW-5A maintained higher viability during the simulated gastric phase, whereas DOW-10 showed an initial decrease in viable counts followed by an increase during the simulated intestinal phase. The two strains also exhibited various probiotic characteristics, including mucin adhesion and antioxidant activity. Atypical, crystalline colony morphologies associated with EPS production were observed when sucrose was supplied as a carbon source. Both strains formed biofilms, while DOW-5A showed a marked increase in biofilm formation upon sucrose supplementation. Neither strain showed gelatinase or hemolytic activity or significant cytotoxicity toward Caco-2 cells. Impact Statement In this study, we isolated two honey-derived S. salivarius strains with high probiotic potential. Our findings highlight wildflower honey as a potential reservoir of LAB with traits relevant to survival under GI and physiological stresses, as well as various probiotic traits.

Biopreservatives including nisin and its derivatives are becoming more desirable in the food processing industry because of the growing demand for naturally preserved and minimally processed foods free from artificial preservatives. However, ensuring microbiological safety while meeting these consumer preferences remains a major challenge. This has necessitated the continuous investigation of potential new antimicrobial agents produced by naturally occurring microorganisms. Hence, this study explored the synthesis, characterisation, and optimisation of a bacteriocinogenic lactic acid bacterium and its antimicrobial product, possibly novel bacteriocin (Nisin 2A) from Lactococcus lactis isolated from commercial brined cheese. The isolation was achieved by screening for wild-type bacteriocin-producing lactic acid bacteria from dairy products using MRS media. Screening was performed using antagonism assays, yielding five producer organisms. Of these, the isolate whose metabolites exhibited the most potent antimicrobial activity was identified as Lactococcus lactis, which synthesised an active antimicrobial peptide designated as Nisin 2A, with a molecular mass of approximately 3.3 kDa as determined by UHPLC-MS and SDS-PAGE. Production of Nisin 2A was scaled up through fed-batch fermentation of Lactococcus lactis in modified MRS broth following process optimisation using a Plackett-Burman experimental design and purified by ammonium sulphate precipitation and solid-phase extraction (SPE). Furthermore, the antimicrobial potential of the bacteriocin was evaluated by the agar well diffusion assay and quantified using the tube dilution method. The purified peptide demonstrated broad-spectrum antimicrobial activity, particularly against the test Gram-positive bacteria Bacillus cereus and retained its bioactivity across a wide pH range (3-9) and high thermal conditions (up to 100 {degrees}C). Furthermore, it had high sensitivity to proteolytic enzymes (Proteinase K and Trypsin). Notably, the peptide was thermostable and retained up to 90% of its initial activity after thermal treatment and maintained consistent inhibitory performance after extended storage. These findings highlight the potential application of Nisin 2A as a natural biopreservative in food systems.

Traditional Mongolian fermented foods have been extensively utilized for dietary regulation and the promotion of gastrointestinal health. However, spontaneous fermentation remains inherently unpredictable, leading to significant variations in microbial community dynamics, metabolite accumulation, and the consistency and quality of the final product. Drawing on the traditional preparation of Mongolian acidic foods, this study established a controlled production strategy for whole-wheat probiotic fermented soup (WWPFS) by combining enzymatic pretreatment with probiotic-directed fermentation. Physicochemical characterization, 16S rRNA gene-based microbial community profiling, LC-MS/MS-based untargeted metabolomics, safety evaluation, and an Escherichia coli-induced gut microbiota dysbiosis model were employed to optimize and comprehensively characterize the fermentation process of WWPFS. The optimized process established a reproducible fermentation system consistently dominated by Lactobacillus and Bacillus across independent fermentation batches. Compared with traditional spontaneous fermentation, probiotic-directed fermentation remodeled the physicochemical properties of the whole-wheat matrix, including carbon, nitrogen, phosphorus, sulfur, and mineral composition, and facilitated the accumulation of putatively annotated LC-MS/MS features, including DL-lactate, 1,4-D-xylobiose, diacetyl, and phenyllactic-acid-related features derivatives. Acute oral and 28-day repeated-dose toxicity evaluations showed no treatment-related adverse effects within the tested dose range and study duration. In the Escherichia coli-induced gut microbiota dysbiosis mouse model, microbial richness, diversity, and community structure differed among the experimental groups, and both low- and high-dose WWPFS groups showed significant shifts in overall gut microbial community composition relative to the model group after multiple-testing correction, together with directional recovery of selected model-responsive bacterial genera. Cross-system integration identified coordinated response patterns between fermentation-derived metabolite features and model-responsive gut bacterial taxa, supporting a potential metabolite-microbiota link in WWPFS-mediated gut microbiota modulation. In summary, probiotic-directed fermentation improved the controllability of the traditional Mongolian fermented food production process, reshaped its metabolic profile, and enhanced its potential to modulate the gut microbiota. These findings provide experimental evidence supporting the modernization of traditional Mongolian fermented foods and the development of probiotic-based functional foods.

This study investigates electro-fermentation candida Tropicalis SY005 to address fermentation kinetics limitation during grape must fermentation. In comparison with non-stimulated control sample, EF substantially enhanced sugar depletion, TSS drop by day 3 and generated a strongly reduced state (ORP -100 to -143mV). The oxidation-reduction shift enhanced cellular NAD+ regeneration, reducing total fermentation duration from 264 h to 72 h. GC-MS analysis showed pronounced major characteristic volatile compound confirming substantial metabolic pathway shifts in flavor of glycolytic flux. Moreover moderate electric field promoted cellular membrane electropermeabilization substantially promoting bioactive extraction.

"Lactic acid bacteria (LAB) are one of the dominant groups of bacteria in the palm sap (Arenga pinnata) microbiome. Previous research in the sago palm sap production centers of Tomohon City (Kayawu, Pinaras, and Lahendong) has successfully identified various LAB species, including Lactobacillus casei, Lactobacillus plantarum, Lactobacillus brevis, Lactobacillus buchneri, Leuconostoc mesenteroides, and Leuconostoc sp. This study aims to identify LAB species in sago palm sap from a new location, namely the Wawo Plantation in Tomohon, and to evaluate their potential as natural antibacterial agents. Through 16S rDNA gene sequencing analysis, the isolates obtained were identified as belonging to the newly described genera Lacticaseibacillus and Lactiplantibacillus. Four promising isolates Lactiplantibacillus fabifermentans A1.4, Lacticaseibacillus casei B1.5, Lacticaseibacillus paracasei B1.6, and Lacticaseibacillus paracasei B3.5 were tested for their inhibitory activity against the enteric pathogens Salmonella sp. and Escherichia coli using the well diffusion method. The results showed that all isolates exhibited a strong spectrum of pathogen inhibition. The highest inhibitory activity against Salmonella sp. was demonstrated by the L. paracasei B1.6 isolate, with an inhibition zone of 21.25 mm, while optimal inhibition against E. coli was achieved by L. casei B1.5 at 11.0 mm. These findings confirm that the local BAL strain from Tomohon palm sap has great potential for large-scale development as a biopreservative in the food industry and as a functional probiotic agent"

Antimicrobial resistance has intensified the search for sustainable natural products with antimicrobial properties. Pleurotus ostreatus cultivated on lignocellulosic agro-wastes, including cassava peel, offers potential for bioactive-compound production and agricultural waste valorization. Conventional antimicrobial screening, however, can be labour-intensive when multiple extracts and pathogens are evaluated. This study evaluated whether extraction solvent, broad pathogen taxonomic category, and batch-level mycochemical composition could predict the antimicrobial response of P. ostreatus extracts cultivated on cassava peel and identified the variables contributing most strongly to prediction. Ethanolic and aqueous mushroom extracts were evaluated against seven microbial pathogens using agar well diffusion and broth microdilution assays. The dataset comprised 42 observations. A Random Forest model with leave-one-out cross-validation (LOOCV) was used to model zone of inhibition as a regression task and minimum inhibitory concentration (MIC) as a binary classification task. The Random Forest regression model showed moderate internal predictive performance for zone of inhibition (R2 = 0.68, MAE = 0.62 mm, RMSE = 0.75 mm). Extraction solvent was the strongest predictor, whereas batch-level mycochemical variables contributed minimally. In contrast, MIC classification performed poorly (accuracy = 0.43; F1-score = 0.33), indicating that the available predictors were insufficient to discriminate the two observed MIC groups. The findings support machine learning as an exploratory complement to antimicrobial screening of mushroom-derived natural products. Given the limited dataset and three cultivation batches, the results are preliminary. Larger, multi-substrate and multi-species datasets with replicate-resolved biochemical measurements will be required to develop robust predictive models.

Cronobacter sakazakii is an opportunistic foodborne pathogen that affects neonates, and has ability to produce dry surface biofilm (DSB). However, little is known about its resistance to dry sanitizers. This study aimed to evaluate the efficiency of dry sanitizers compared with sodium hypochlorite (SH) on DSB of C. sakazakii. DSB were formed on stainless steel or polypropylene coupons (10 cm{superscript 2}) using two cycles of hydrated/dry phases at 25 {degrees}C: T1 (48/48 h) or T2 (24/120 h). At DSB endpoint, the coupons were sanitized with 70% ethanol, a commercial product based on isopropyl alcohol (25%) and quaternary ammonium (0.015%), hot air (90{+/-}2 {degrees}C), UV-C light (254 nm), gaseous ozone (45{+/-}2 mg/L), or SH (200 mg/L, pH 6.5). All dry sanitizers showed limited antimicrobial activity (p > 0.05), with reductions [&le;] 0.8 log CFU/cm{superscript 2} over 30 min exposure. In contrast, SH was effective against DSB regardless of the DSB formation protocol, with reductions [&ge;]2 and >5 log CFU/cm{superscript 2} after 10 and 30 min, respectively. Interestingly, DSB formed with shorter hydrated phase and longer dry phase (T2) had greater sensitivity to SH, but it was not noted to dry sanitizers. CLSM images suggested the presence of VBNC cells, particularly after SH treatment. In conclusion, our results emphasize the importance of implementing stringent hygiene measures to control C. sakazakii DSB in the low moisture food industry, and indicate that SH is an effective sanitation strategy when the drying line is promptly addressed.

The crystal violet (CV) microtiter plate assay is widely used to compare microbial biofilm formation because it is inexpensive, simple, and readily adapted to 96-well formats. Its high-throughput design enables multiple strains, growth conditions, and treatments to be tested in parallel, but increasing experimental complexity can make downstream data handling difficult. Plate layouts, absorbance measurements, blank correction, replicate analysis, and visualization are often managed using separate spreadsheets or software, requiring repeated transfer and organization of experimental information. This can compromise consistency in linking measurements with their corresponding conditions and controls. We developed BiofilmQ-HT, a standalone, browser-based workflow that integrates plate annotation with direct import of plate-reader data, condition-specific blank correction, replicate summarization, growth-normalized specific biofilm formation (SBF) analysis, percentage-inhibition analysis, visualization, and data export. The workflow was applied to three representative datasets: a comparison of biofilm formation in 25% and 100% media, an analysis of bacteriophage- and antibiotic-associated antibiofilm activity, and a screening of biofilm formation among natural microbial isolates. These applications demonstrate a common analytical framework for comparative biofilm analysis, antibiofilm screening, and high-throughput isolate screening while retaining experimental conditions and controls. By linking plate organization to quantitative analysis and reporting, BiofilmQ-HT provides a reproducible and traceable approach for processing condition-rich CV assay datasets and facilitates consistent comparisons across experimental groups. The utility therefore improves consistency in data handling without altering the underlying experimental assay or requiring changes to the established assay.

Amplicon surveys of fermented and spoiled foods routinely resolve Lactobacillaceae, the lactic acid bacteria responsible for many food and beverage fermentations, only to genus, whereas registers such as the Inventory of Microbial Food Cultures require species-level identification. This shortfall arises from the 16S rRNA genes limited, region-dependent resolution and from incomplete, non-type-strain-anchored references that silently reassign missing species to their nearest relative. We built LactoTypeDB, a regenerable, type-anchored reference covering 434 of the familys 441 species and all 37 genera and substituted it into the Living Tree Project release LTP 08_2023 the fields default classifier uses. This eliminated species-level misassignment of type strains in all regions tested and cut misassignment of 10,329 other sequences from the same species from 1,374 errors down to 3 when the full-length 16S rRNA gene was used. Applied unmodified to 11,612 V3-V4 distinct sequences from a published survey of two meat production lines, the workflow returned a species for 213 and a genus for 5,926, and flagged 3,495 as undescribed candidates, more than a third of them nearest to Dellaglioa, a genus that includes a meat-spoilage organism tracked in that survey. The ambiguity that remains is the markers, since V3-V4 collapses 417 of the 434 species into 27 groups it cannot separate. For food microbiology laboratories, the practical change is that a species call from this family can now be trusted where the marker allows it, and a sequence matching nothing becomes a candidate worth isolating rather than a limitation to work around.

Rinsing-dependent dental hygiene presents a significant public health challenge in water-scarce environments. This study investigated combinations of xylitol (Xyl), chitosan (Chi), glycyrrhizin (Gly), epigallocatechin gallate (EGCG), dicalcium phosphate (DCP), and nano-hydroxyapatite (nHA) on the primary bacteria behind dental caries, S. mutans. These combinations were assessed for markers of dental caries by biofilm reduction, bacterial killing, and acid buffering against S. mutans when applied to an in vitro simulated enamel model using glass bead surfaces for biofilm formation, and gene expression was subsequently examined via RT-qPCR. Separately, mineral retention was also quantified. The EGCG-DCP-Xyl film demonstrated the highest overall efficacy, achieving a significant reduction in biofilm concentration compared to the untreated control and performing similarly in magnitude to the positive toothpaste control. Dead fluorescence staining confirmed that the EGCG-DCP-Xyl film induced the highest rate of non-viable cells, followed by the Chi-Gly film and the Gly-Xyl film. During 10-day pH cycling, the EGCG-DCP-Xyl and DCP-Xyl formulations buffered pH the most, consistently maintaining mean pH levels safely above the demineralization threshold of pH 5.5. The EGCG-DCP-Xyl also optimized mineral stability with the highest retained calcium concentration, significantly outperforming the Chi-Xyl film. At the transcript level, the EGCG-DCP-Xyl film induced substantial downregulation of key virulence genes, yielding decreases in expression for glucosyltransferase B (gtfB), associated with biofilm synthesis, collagen-binding protein (cnm), associated with tissue invasion, and lactate dehydrogenase (ldh), associated with lactic acid production, compared to the untreated control, with effects comparable in magnitude to the positive toothpaste control. This research suggests that targeting bacterial pathways and mineral loss through a portable film may have potential for preventing dental caries, especially in environments where water is limited. However, additional studies are necessary to evaluate real-world effectiveness.

Spontaneous vegetable fermentation is driven by the indigenous microbiota associated with the raw ingredients. The process often involves an initial heterofermentative phase followed by a predominantly homofermentative phase, both ensured by lactic acid bacteria (LAB). While microbial dynamics during fermentation are well characterized, phage communities remain poorly understood, despite evidence linking phage activity to LAB succession. We monitored viral and bacterial succession during sauerkraut and carrot fermentations using a metagenomics approach to characterize community dynamics. To further assess the impact of phage PLE001 on bacterial community dynamics, we developed a simplified carrot fermentation model comprising representative strains of Rahnella aquatilis, Leuconostoc mesenteroides and Lactiplantibacillus plantarum. Two consortia were assembled: one containing the PLE001-susceptible strain L. mesenteroides CIM3004, and the other containing also its phage-resistant derivative, CIM3004 BIM. We observed major shifts in the viral community during the first week of fermentation, coinciding with changes in bacterial structure during hetero- and homofermentative phases transition. In the simplified model, phage PLE001 reduced the population of the host during the heterofermentative phase but did not affect overall fermentation dynamics nor metabolite production. These results suggest that bacteriophages contribute to bacterial succession during fermentation, while communities remain resilient to phage infection, preserving fermentation stability.

Nisin is a promising antimicrobial peptide widely used in food preservation due to its efficacy against Gram-positive spoilage and pathogenic bacteria. Although Nisin is increasingly applied in the food sector, the biopeptide suffers from instability within food matrixes and can rapidly lose its antimicrobial potential following interaction with food biomolecules. Thus, it is necessary to investigate approaches that can be employed to extend the stability and activity of Nisin. Hence, the aim of this study was to develop and characterise a chitosan-alginate polyelectrolyte microencapsulation system capable of enhancing Nisin stability while retaining antimicrobial activity. The microencapsulation of Nisin was achieved by pre-gelation of alginate using calcium chloride and subsequent direct electrostatic interaction between cationic Nisin and chitosan with pre-gelled anionic alginate at pH 5.0. Following microcapsule formation, physicochemical and structural characterisation was performed using Zeta potential determination and measurement of the polydispersity index (PDI) via dynamic light scattering. SEM micrographs were used to confirm morphology, while Fourier-transform infrared (FTIR) spectroscopy and high-performance liquid chromatography (HPLC) were utilised to assess chemical integrity and functional group preservation of encapsulated Nisin. Following this, stable microcapsules with diameters ranging from 150-200 nm and smooth surface morphology were obtained. Microcapsule formation was strongly influenced by formulation parameters, particularly pH, calcium ion concentration, and chitosan content, with deviations from optimal acidic conditions (< pH 5.0) resulting in aggregation, increased polydispersity, and reduced encapsulation efficiency. The microcapsules were monodispersed (PDI {approx} 0.30) and electrostatically stable, exhibiting a Zeta potential of approximately +36 mV. These microcapsules remained stable over a prolonged storage period of 21 days under refrigerated conditions while retaining antimicrobial activity against Bacillus cereus. Encapsulation efficiency reached approximately 65%, confirming effective retention of Nisin within the polymer matrix. Overall, the findings demonstrate that chitosan-alginate ionic gelation is a non-denaturing and effective encapsulation strategy for extending the functional stability of Nisin. These microcapsules show strong potential as natural antimicrobial delivery systems for food and beverage applications, particularly in acidic food matrices, with implications for improved food safety and shelf-life extension.

Why was the work done?: Gluten-free (GF) beers typically exhibit poorer foam stability than conventional barley malt-based beers, yet the molecular basis underlying this difference remains poorly understood. This study aimed to investigate protein-level factors associated with foam stability in GF and barley beers. How was the work done?: Three commercially produced GF beers, comprising two lagers brewed from rice or sorghum, and one pale ale brewed from a millet-buckwheat-rice blend, were compared with two commercially produced barley-malt beers, comprising a lager and a pale ale. Soluble protein was isolated from freeze-dried beer powder using TCA-acetone. Protein profiles were examined using SDS-PAGE, and proteomes were characterised and compared using label-free quantitative LC-MS/MS. What are the main findings?: GF beers showed lower soluble protein concentrations and significantly lower foam stability than the barley beers. SDS-PAGE revealed fewer and weaker protein bands in GF beers compared with barley beers. Proteomic analysis showed that barley beers were enriched in known foam-active proteins, particularly lipid transfer protein 1 (LTP1) and Protein Z (serpin family members), whereas these proteins were not detected or were detected only at very low levels in GF beers.

BackgroundAlthough human milk (HM) confers important health benefits, how bioactive milk components (e.g., microbiota, oligosaccharides, and fatty acids) interact with infant genetics to influence childhood atopy remains poorly understood. ObjectiveWe investigated interactions between infant genomic susceptibility and exposure to maternal human milk components (HMCs) and assessed whether integrating these genetic and milk features improves prediction of childhood atopy. MethodsLeveraging infant genomic and maternal HMC data from the CHILD Cohort Study, we conducted gene-milk interaction analysis using linear regression models that integrated polygenic risk scores (PRS) of nursing infants with multiple HMC types. Gradient-boosting machines (GBMs) were used to evaluate predictive performance of HMCs and infant PRS for childhood atopy. ResultsChildhood atopy was associated with interactions between infant genomics (e.g., PRS associated with atopy) and exposure to specific human milk microbes (e.g., Abiotrophia, PBonf=0.005, {beta}=0.29), as well as networks of co-occurring HMCs (e.g., a module containing Bifidobacterium longum, 2-fucosyllactose, and eicosapentaenoic acid, P=0.009, {beta}=-12.3). A GBM integrating HMCs and infant PRS achieved the highest predictive performance for childhood atopy with an area under the curve (AUC) of 0.78, outperforming models based on individual HMC types or PRS alone (AUC range: 0.54-0.63). ConclusionIntegration of maternal HMC exposures with infant genomics reveals interaction effects that contribute to prediction of childhood atopy. Understanding how early-life exposures such as HMCs impact the health of children differently depending on their genomic profiles may facilitate the development of personalized intervention strategies to reduce the burden of these health outcomes during childhood. Key messagesO_LIInteractions between infant polygenic risk and exposure to human milk components are associated with childhood atopy. C_LIO_LINetworks of co-occurring human milk microbiota, oligosaccharides, and fatty acids may influence childhood atopy, with effects varying by infant genomic susceptibility. C_LIO_LIIntegration of human milk components with infant genomics improves prediction of childhood atopy compared with individual milk components or genomics alone. C_LI Capsule SummaryThis study demonstrates that interactions between infant polygenic risk and maternal milk components improve prediction of childhood atopy, highlighting opportunities for personalized early-life prevention strategies.

The anaerobic biotransformation of lindane ({gamma}-hexachlorocyclohexane), a persistent legacy pesticide and challenging subsurface contaminant was modelled using an integrated Monod biokinetics framework. Calibrated against batch experimental data, this model accounted for the dissolution of solid phase lindane and the thermodynamics of reactions involved. The study focused on a methanogenic, lindane-degrading enrichment culture (GT2) that used ethanol as the electron donor, where ethanol fermentation supplied hydrogen to support reductive dechlorination of lindane. A Dehalobacter strain was identified as the lindane-degrading organism, while a member of bacterial order Geobacterales carried out ethanol fermentation. First-order decay constants for lindane-degrading Dehalobacter were estimated from experimental data and showed variation across different growth conditions. The biokinetics model captured interactions among key microbial processes, namely lindane dechlorination, ethanol fermentation, hydrogenotrophic methanogenesis, and acetoclastic methanogenesis. Thirteen biokinetics parameters including maximum substrate utilization rates (k), half-velocity constants (Ks), and decay constants for these microbial processes were estimated through a Bayesian optimization approach. Global sensitivity analysis showed that eight parameters, primarily k and Ks, had significant linear impact on the model output, whereas responses to decay constants were more variable and potentially non-linear. This study proposed an effective modelling approach for characterizing syntrophic microbial growth within enrichment cultures and provides valuable biokinetics parameters estimates for real-world applications of anaerobic lindane bioremediation.